Search

Abstract\nNOVELTY STATEMENTSAluminum (Al) is a trace element that may hamper plant growth and development. Tolerance mechanisms could imply the cell wall as it is the first barrier before entry into the plant cell. Douglas-fir plantlets were grown in vitro on media supplemented with different aluminum chloride (AlCl3) concentrations up to 1 mM. The characterization of the cell wall revealed quantitative and qualitative modifications in the polysaccharidic composition of the wall, in particular in roots whose pectins showed a higher galacturonic acid content with less ramification and a lower degree of methylesterification (DME) explained by a higher pectin methylesterase activity; these Al-induced changes suggest an Al-trapping process in cell wall structures. In stems and needles, the observed increase in DME rather suggests an exclusion of Al from the cell wall.Douglas-fir is a coniferous species that has shown tolerance against trace elements such as aluminum. In this study, changes in cell wall polysaccharides were observed in plants grown in the presence of Al, notably in roots. The contents and the structures of pectins were affected, leading to a trapping process in roots due to an abundance of low methylesterified pectins, and an exclusion process from the cell wall in stem and needles with less Al-binding sites in pectins. [ABSTRACT FROM AUTHOR]

As one of the most influential environmental factors, light fundamentally shapes plant physiology and growth traits. 1,2,3,4,5,6,7,8,9,10 The hypocotyl is critical for the morphological establishment of the seedling, and its length displays remarkable plasticity upon perception of changes in the light conditions. 4,5,8,9,10,11,12,13,14,15 Although remodeling of the primary cell walls is well-documented to play an important role in hypocotyl growth, how the hypocotyl elongation rate is swiftly repressed at the dark-to-light transition remains elusive. 16,17,18,19,20,21,22,23,24,25 Here, we show that expression of an Arabidopsis microRNA, miR775, is quickly inhibited at the dark-to-light transition by ELONGATED HYPOCOTYL 5 (HY5), an essential negative regulator of hypocotyl elongation that is degraded in the dark and accumulates in the light. 26 We found that this repression allows the miR775-targeted GALACTOSYLTRANSFERASE 9 (GALT9) to accumulate in the transverse walls of hypocotyl cells within 10 min of light exposure. Genetic analysis coupled with time-lapse photography demonstrates that GALT9 is both necessary and sufficient for controlling the differential hypocotyl growth rates at the dark-to-light transition. Immunohistochemical analysis and coherent Raman microscopy reveal that the polarized accumulation of GALT9 confers a rapid increase in the pectin content of the transverse walls. Atomic force microscopy (AFM) confirms that polarized pectin accumulation mediated by the HY5-miR775-GALT9 repression cascade correlates with rapid asymmetric increases in cell wall rigidity and hence decreases in cell elongation in the light. Together, these findings add new insights into the cellular mechanism governing differential hypocotyl growth at the dark-to-light transition and should also benefit the general understanding of polarized cell expansion in plants. [Display omitted] • Triggered by light, GALT9 accumulates in the transverse walls of hypocotyl cells • GALT9 polarization confers a rapid increase in pectin level and mechanical stiffness • Such polarization slows down longitudinal growth of the hypocotyl Hypocotyl elongation is rapidly repressed when dark-grown plants are exposed to light. Zhang et al. show that the HY5-miR775-GALT9 pathway allows preferential GALT9 accumulation in the transverse walls at the dark-to-light transition, which increases pectin level and mechanical stiffness of the transverse walls to inhibit longitudinal growth. [ABSTRACT FROM AUTHOR]

The side effects associated with the chemotherapy of triple-negative breast cancer (TNBC), such as nucleotide-binding oligomerization domain (NOD)-like receptor family (NLR), pyrin domain containing 3 (NLRP3) inflammasome activity, are responsible for the treatment failure and high mortality rates. Therefore, advanced delivery systems have been developed to improve the transport and targeted administration of anti-tumor agents at the tumor sites using tissue engineering approaches. Implantable delivery systems based on biodegradable polymers are an effective alternative due high biocompatibility, porosity, and mechanical strength. Moreover, the use of paclitaxel (PTX)-cyclodextrin complexes increases the solubility and permeability of PTX, enhancing the bioavailability and efficacy of the drug. All of these properties contribute to the efficient encapsulation and controlled release of drugs, preventing the damage of healthy tissues. In the current study, we detailed the synthesis process and evaluation of 3D scaffolds based on gelatin functionalized with methacryloyl groups (GelMA) and pectin loaded with PTX–cyclodextrin inclusion complexes on TNBC pathogenesis in vitro and in vivo. Bio-physio-chemical analysis of the proposed scaffolds revealed favorable mechanical and biological properties for the cellular component. To improve the drug solubility, a host–guest interaction was performed by the complexation of PTX with a cyclodextrin derivative prior to scaffold synthesis. The presence of PTX suppressed the growth of breast tumor cells and promoted caspase-1 activity, the release of interleukin (IL)-1β, and the production of reactive oxygen species (ROS), conditioning the expression levels of the genes and proteins associated with breast tumorigenesis and NLRP3 inflammasome. The in vivo experiments suggested the activation of pyroptosis tumor cell death, confirming the in vitro experiments. In conclusion, the bio-mechanical properties of the GelMA and pectin-based scaffolds as well as the addition of the PTX–cyclodextrin complexes allow for the targeted and efficient delivery of PTX, suppressing the viability of the breast tumor cells via pyroptosis cell death initiation. [ABSTRACT FROM AUTHOR]

This study aimed to develop and characterize biodegradable films made from pectin, pomegranate seed oil, and different microalgae (Spirulina platensis, Chlorella sp., and Scenedesmus obliquus) and to evaluate their applicability as packaging by verifying their effect on the conservation and postharvest quality of cajarana (Spondias dulcis). The films proposed in this study were assessed for their physical, optical, and mechanical attributes, as well as the physicochemical characteristics of the fruits coated with the films after 14 days of storage at 10 ± 1 °C and relative humidity of 60 ± 5%. Incorporating microalgae improved the homogeneity and mechanical properties, decreasing breaking stress, elastic modulus, and maximum tensile strength, contributing to a lower solubility and improving the barrier properties of the films compared to the control (T1). The film formulated with 6% citric pectin, 40% glycerin, 0.5 mL·L−1 pomegranate seed oil (PSO), and 0.05% Scenedesmus obliquus showed better performance in solubility, water vapor permeability (WVP), and mechanical properties, maintaining gloss and transparency, approaching the performance of the commercial PVC film. The film was formulated with 6% pectin + 40% glycerin + 0.5 mL·L−1 PSO + 0.05% Chlorella sp. maintained the postharvest quality of cajarana fruits, allowing the conservation of the physicochemical quality of the fruits after 14 days of storage at 10 ± 1 °C and 60 ± 5% RH. [ABSTRACT FROM AUTHOR]

In this work, an innovative three-layer sensor was developed in a fully sustainable design. For that purpose, pectin and anthocyanins from Morus nigra and Prosopis alba were used. Furthermore, mixtures of beeswax and colophony as hydrophobic layers were used to prevent the moisture from affecting the sensor work. The ratio of beeswax/colophony (B/C) was studied to optimize the moisture barrier. The response of colorimetric sensors pectin-Morus nigra (PMN) and pectin-Prosopis alba (PPA) in vapors of simulant solutions was recorded. Furthermore, physicochemical and microbiological tests on fresh bovine meat were carried out, and volatile compound content (VC) was correlated with color changes in PMN and PPA sensors. The results depicted that the optimal ratio in the waterproof layer was B/C: 70/30 (BC3) showing the highest water contact angle of 112° and minimal water vapor absorption value of 2.4%. In addition, the light transmittance of the BC3 layer allows to perceive the color of the sensor without alteration. The outcomes of the simulation test showed differences in color values of 26 and 31 to PMN and PPA, respectively, highlighting the ability of both sensors to allow the detection of quality changes in packaged bovine meat. This research paves the way for the development of sustainable and environmentally friendly colorimetric sensors with diverse applications. [ABSTRACT FROM AUTHOR]

The aim of this study was to optimize sequential ultrasound-radio frequency–assisted extraction (URAE) of pectin from pomelo peel. Effects of sonication power and time, radio frequency (RF) heating temperature, and time on the pectin yield (PY) were evaluated. Based upon optimized URAE parameters, the yield, physicochemical, and structure properties of pectin recovered from sequential radio frequency-ultrasound–assisted extraction (RUAE), ultrasound-assisted extraction (UAE), and RF-assisted extraction (RFAE) were also compared. A maximal PY of 28.36 ± 0.85% was attained at the optimized URAE conditions including solvent pH of 1.5 (citric acid), sonication at 183 W for 24 min, and RF heating at 87 °C for 23 min. Although all four samples had a high degree of esterification more than 50%, URAE was the lowest. No significant changes were observed in the types of monosaccharides among different samples. Furthermore, all four samples (6.6–10.3 mg GAE/g) showed significantly higher total phenolic content than those of commercial citrus pectin (1.2 mg GAE/g), and among them, RFAE was the highest with the best antioxidant capacity. The water and oil holding capacities of the four samples were between 3.5 to 4.0 and 2.6 to 3.0 g/g, respectively, but there was no significant difference (p > 0.05) between each other. Structure properties indicated that there were no significant differences in the main chemical structures among the four pectin samples. Morphology analysis of URAE showed a more compact, smoother, and flatter surface than that of RUAE and RFAE. The results observed in this paper suggest that sequential URAE is an efficient strategy for the recovery of high-quality pectins. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) contamination in agricultural soil brings severe health risks through the dietary intake of Cd‐polluted crops. The comprehensive role of pectin in lowering Cd accumulation is investigated through low Cd accumulated (L) and high Cd accumulated (H) cultivars of L. sativa. The significantly different Cd contents in the edible parts of two L. sativa cultivars are accomplished by different Cd transportations. The pectin is the dominant responsive cell wall component according to significantly increased uronic acid contents and the differential Cd absorption between unmodified and modified cell wall. The chemical structure characterization revealed the decreased methyl esterification in pectin under Cd treatment compared with control. Significantly brighter LM19 relative fluorescence density and 40.82% decreased methanol in the root pectin of L cultivar under Cd treatment (p < 0.05) supported that the de‐methyl esterification of root pectin is more significant in L cultivar than in H cultivar. The pectin de‐methyl esterification of L cultivar is achieved by the upregulation of pectin esterases and the downregulation of pectin esterase inhibitors under Cd treatments, which has facilitated the higher Cd‐binding of pectin. Our findings provide deep insight into the differential Cd accumulation of L. sativa cultivars and contribute to the understanding the pollutant behaviors in plants. Summary statement: Cd‐pollution safe cultivar (Cd‐PSC) with low Cd accumulation in edible parts is a promising strategy to minimize the Cd pollution risk of crops and guarantee food security even in Cd pollution soil. Our study has illustrated the role of root pectin de‐methyl esterification in determining the Cd accumulation in L. Sativa through comprehensive physiological, chemical characterization, and molecular methods, supporting de‐methyl esterification of pectin in L cultivar plays a more prominent role in root pectin detaining Cd. We believe that our study makes a significant contribution to understanding different Cd accumulation mechanisms and molecular‐assistant Cd‐PSC breeding of Lactuca Sativa. [ABSTRACT FROM AUTHOR]

Heavy metal pollution is a worldwide problem that threaten agricultural production and human health. Methyl jasmonate (MeJA) is a phytohormone that could enhance plant resistance against various stresses. However, the mechanism of MeJA in cadmium (Cd) uptake, distribution, and translocation in rice plants remains elusive. In this study, we found that the Cd induced-growth inhibition was ameliorated by MeJA. Upon MeJA application, Cd content in root and shoot was decreased by 10.15 % and 36.39 %, which paralleled with less Cd2 + influx of rice roots and depressed expression of the cation transporters (OsNramp1 and OsNramp5). The subcellular distribution revealed that MeJA enriched Cd distribution in cell wall, which was accompanied by increased cell wall thickness and altered cell wall polysaccharide (pectin, cellulose, hemicellulose) content, meanwhile, the Cd content in pectin, cellulose, hemicellulose was increased, the FTIR analysis implied that functional groups (especially -OH and COO-) on cell wall were involved in Cd fixation. The root to shoot translocation of Cd was hindered by exogenous MeJA, this was validated by the decreased expression of OsHMA2 in root and declined Cd level in xylem sap. Overall, our results revealed that MeJA could act as a foliar resistance control substance to reduce Cd accumulation in rice plants. The detailed molecular mechanisms of MeJA in Cd detoxification in plants still need further investigation. • The Cd-induced growth inhibition of rice seedlings was alleviated by MeJA. • The root, shoot and overall Cd accumulation in rice seedlings were limited by MeJA. • The MeJA reduced net Cd2+ influx by depressing OsNRamp1 and OsNRamp5 expression. • The MeJA inhibited Cd translocation from root to shoot and Cd content in xylem. • The MeJA reconstructed cell wall components and improved its Cd fixation capability. [ABSTRACT FROM AUTHOR]

Key message: Carrot callus grown on a medium with increased nitrogen have reduced carotenoid accumulation, changed gene expression, high amount of vesicular plastids and altered cell wall composition. Carotenoid biosynthesis is vital for plant development and quality, yet its regulation under varying nutrient conditions remains unclear. To explore the effects of nitrogen (N) availability, we used carrot (Daucus carota L.) model callus cultures in vitro as a controlled system for studying nutrient-regulated metabolic processes. Two mineral media differing in N content and NO₃⁻/NH₄⁺ ratios were used. Comprehensive analyses, HPLC, transmission electron microscopy, immunochemistry, and RNA sequencing, revealed notable cellular and molecular responses to N treatments. The results demonstrated that N supplementation reduced carotenoid content by 50%, particularly β-carotene and α-carotene. The composition of chromoplast types shifted, with vesicular chromoplasts dominating (55%), followed by a globular type (23%), while in the control callus, globular and crystalline types predominated (57% and 33%, respectively). Immunohistochemistry showed increased presence of high-esterified pectins and arabinogalactan proteins in N-treated cells. Transcriptomic analysis identified 1704 differentially expressed genes (DEGs), including only two in the carotenoid biosynthesis pathway: phytoene synthase 2 (PSY2) and zeaxanthin epoxidase (ZEP). PSY2, which encodes the carotenoid rate-limiting enzyme, showed expression levels that corresponded with reduced carotene content. Other DEGs included 15 involved in nitrogen transport, 1 in nitrogen assimilation, 40 in cell wall biosynthesis and modification, and 9 in phenylpropanoid/flavonoid pathways. N-treated callus exhibited altered expression of MADS-box, NLP, bZIP, and ethylene-responsive transcription factors. These findings reveal how nitrogen availability disrupts carotenoid biosynthesis and triggers extensive chromoplast and cell wall remodeling, providing a cellular framework for understanding nutrient-regulated metabolic shifts. [ABSTRACT FROM AUTHOR]

The use of green solvents, citric acid (CA), and natural deep eutectic solvents (NADES) for the obtention of pectin from wastes (pulp and peel) of Malus domestica was studied. The NADES used comprised citric acid–glucose–water (N1) or lactic acid–glucose–water (N2). The fractions rich in pectin obtained after exposure to NADES showed lower yield (≈4 g/100 g CA vs. ≈ 11 g/100 g CA), equal to or lower degree of methoxylation (53–71 mol/100 mol CA vs. 73 mol/100 mol CA), equal to or greater content of uronic acid (50–63 g/100 g CA vs. 51 g/100 g CA) than those isolated with CA, and the ones obtained from peel were the most thermally stable. These pectins showed greater linearity, shorter branch lengths, and lower arabinose content than those obtained with CA. The neutral sugars present in the highest concentration in all the isolated fractions were arabinose, xylose, galactose, and rhamnose. Glucose was also detected, probably due to contamination with starch. Their aqueous solutions showed pseudoplastic behavior. The effect of ultrasound assistance was preliminarily evaluated in the production of pectic fractions using N2, observing higher yields (13–18 g/100 g), in general, a higher concentration of uronic acid and a higher degree of methoxylation when compared with the extraction without US. They also showed greater arabinose content (less degradative treatment), lower glucose content (increased purity), and higher rhamnogalacturonan I (RG-I) content. It is known that RG-I is linked to pectin bioactivity and rheological behavior. The green solvent techniques assayed allowed obtaining fractions rich in uronic acid with different chemical, thermochemical, and rheological characteristics. In the case of isolation with NADES, the yield was low, but preliminary tests with ultrasound assistance showed that it is possible to overcome this limitation. [ABSTRACT FROM AUTHOR]

AbstractThe effects of four groups of hot-air drying methods, including constant temperature (50 °C) and constant humidity (10%) (CTCH), constant temperature (50 °C) and variable humidity (60%-47%-35%-23%-10%) (CTVH), variable temperature (40 °C-46 °C-52 °C-58 °C-64 °C) and constant humidity (10%) (VTCH), variable temperature (40 °C-46 °C-52 °C-58 °C-64 °C) and variable humidity (60%-47%-35%-23%-10%) (VTVH), on the drying kinetics, product quality and the content of pectin polysaccharides in cell wall of wolfberry were studied. Among them, VTVH showed the highest drying efficiency with the shortest drying time of 13 h, which was 9.52% shorter than that of CTCH, and the highest effective water diffusion coefficient for wolfberries (9.356 × 10−9 m2·min−1). After VTVH drying, samples showed the highest polysaccharides content (46.48%) and rehydration rate (52.24%), as well as the lowest color difference (6.07) and shrinkage rate (66.38%). The content of water-soluble pectin (WSP) in wolfberry was the highest under VTCH drying condition, which was 48.67% higher than that of CTVH drying condition. [ABSTRACT FROM AUTHOR]

The recovery of polysaccharides (PS) from red grape marc and white grape pomace by enzymatic degradation of their cell walls is an interesting green extraction technique that preserves the structure and bioactivity of PS. The type and dose of enzyme, and the liquid/solid (L/S) ratio in PS extraction were studied using four commercial enzymes. Four different doses per enzyme were used, with tartaric acid as solvent and L/S ratios of 1.3/1 and 4/1 for 24 h at 20 °C, compared with a control. The highest dose of enzyme E1, polygalacturonase + pectin lyase + pectin-methyl-esterase (with the highest activity) was the most effective in the degradation of high and medium molecular weight PS. At the lower L/S ratio, the fact that the highest dose of E1 degraded a higher percentage of high and medium molecular weight PS in the marc was explained by the difference in cell wall deconstruction between pomace and marc. The highest total PS purity was achieved in pomace with E1 at the maximum dose in both ratios, and in marc at the 1.3/1 ratio. The extraction efficiency of total PS was low for all enzymes. In the future, extraction with E1 combined with other green extraction techniques will be studied. [ABSTRACT FROM AUTHOR]

AbstractInfrared microspectroscopy allows for detailed characterization of functional groups at subcellular levels in plants. In this study, barley leaves were inoculated with Blumeria graminis f. sp. hordei (Bgh, adapted) and B. graminis f. sp. tritici (Bgt, nonadapted). Globar-based transmission Fourier transform infrared (gFTIR) microspectroscopy equipped with an upgraded high-resolution focal plane array (FPA) detector which enabled the rapid acquisition of high magnification imaging with a 3.3-μm × 3.3-μm capacity, was employed to quantitatively analyse the cell wall (CW) modification over individual leaf cells in response to attempted penetration at 24 hours post-inoculation. Univariate and multivariate analyses of gFTIR spectra revealed distinct changes in several CW functional groups upon attempted penetration by Bgt, with significant increases in the integrated areas of cellulose, hemicellulose, methyl-esterified pectins and lipid regions compared to cells without penetration. Notably, neither guaiacyl (G) nor syringyl (S) lignin increased significantly in CWs near Bgt penetration sites relative to nonpenetrating controls, though the G/S ratio was higher than in Bgh-penetrated sites. These findings suggest early and rapid CW modifications occur during the nonhost resistance to Bgt. This study also confirms previous results obtained using synchrotron-based FTIR (sFTIR), demonstrating that both gFTIR and sFTIR are valuable for studying plant CW apposition, with gFTIR being more accessible and rapid for imaging over large areas with compatible quality and resolution to sFTIR. [ABSTRACT FROM AUTHOR]

Pectin is a complex plant heteropolysaccharide whose structure and function differ depending on its source. In animal feed, breaking down pectin is essential, as its presence increases feed viscosity and reduces nutrient absorption. Soybean meal, a protein-rich poultry feed ingredient, contains significant amounts of pectin, the structure of which remains unclear. Consequently, the enzyme activities required to degrade soybean meal pectin and how they interact are still open questions. In this study, we produced 15 recombinant fungal carbohydrate-active enzymes (CAZymes) identified from fungal secretomes acting on pectin. After observing that these enzymes were not active on soybean meal pectin when used alone, we developed a semi-miniaturized method to evaluate their effect as multi-activity cocktails. We designed and tested 12 enzyme pools, containing up to 15 different CAZymes, using several hydrolysis markers. Thanks to our multiactivity enzymatic approach combined with a Pearson correlation matrix, we identified 10 fungal CAZymes efficient on soybean meal pectin, 9 of which originate from Talaromyces versatilis. Based on enzyme specificity and linkage analysis, we propose a structural model for soybean meal pectin. Our findings underscore the importance of combining CAZymes to improve the degradation of agricultural co-products. [ABSTRACT FROM AUTHOR]

Highlights: This review provides a detailed account of engineered plant cell wall (CW)-mimetic soft materials, which are designed to replicate the intricate composition, structure, and mechanical properties of natural plant CWs. Experimental methods to create CW-like materials are reviewed, and relevant characterization techniques, including mechanical, chemical, structural, and morphological analyses, are discussed. The applications of CW-like materials in several fields, including food packaging, edible films, drug delivery, construction materials, and biocatalysis are highlighted. Plant cell wall (CW)-like soft materials, referred to as artificial CWs, are composites of assembled polymers containing micro-/nanoparticles or fibers/fibrils that are designed to mimic the composition, structure, and mechanics of plant CWs. CW-like materials have recently emerged to test hypotheses pertaining to the intricate structure–property relationships of native plant CWs or to fabricate functional materials. Here, research on plant CWs and CW-like materials is reviewed by distilling key studies on biomimetic composites primarily composed of plant polysaccharides, including cellulose, pectin, and hemicellulose, as well as organic polymers like lignin. Micro- and nanofabrication of plant CW-like composites, characterization techniques, and in silico studies are reviewed, with a brief overview of current and potential applications. Micro-/nanofabrication approaches include bacterial growth and impregnation, layer-by-layer assembly, film casting, 3-dimensional templating microcapsules, and particle coating. Various characterization techniques are necessary for the comprehensive mechanical, chemical, morphological, and structural analyses of plant CWs and CW-like materials. CW-like materials demonstrate versatility in real-life applications, including biomass conversion, pulp and paper, food science, construction, catalysis, and reaction engineering. This review seeks to facilitate the rational design and thorough characterization of plant CW-mimetic materials, with the goal of advancing the development of innovative soft materials and elucidating the complex structure–property relationships inherent in native CWs. [ABSTRACT FROM AUTHOR]

AbstractUlcerative colitis, a chronic inflammatory condition of the colon, requires precise and targeted treatment, and polysaccharides, with their pH responsiveness and biodegradability, offer an innovative approach for colon-specific drug delivery. This study aims to develop a highly precise drug delivery system with enhanced therapeutic and targeting efficiency for ulcerative colitis, focusing on the preparation, optimisation, and evaluation of dual cross-linked mesalamine-loaded sericin-pectin (DCLSPs) micro-beads. These beads utilise the pH-responsive and microflora biodegradability properties of polysaccharides for targeted colon delivery, employing the Response Surface Methodology. Formulated via the ionotropic gelation method with divalent cross-linking ions (Ca2+ and SO42–), the DCLSPs were optimised using a Box-Behnken design to assess the impact of the varying drug, pectin, and sericin polymer proportions. The DCLSPs were evaluated for entrapment efficiency, thermal behaviour, surface morphology, water uptake, swelling, and in-vitro drug release. Results indicated that spherical beads were successfully developed, with encapsulation efficiency ranging from 65.1% to 95.5%, drug loading between 32.5% and 49.9%, bead sizes of 0.75 mm to 0.92 mm, and degrees of swelling from 0.92 to 1.82. Drug release was controlled by both diffusion and swelling mechanisms, as supported by the Higuchi and Korsmeyer-Peppas models. The optimised formulation demonstrated high drug encapsulation efficiency, pH-responsive swelling, and strong adhesion to the colon, ensuring extended retention at the targeted site. Additionally, the incorporation of sericin enhanced the accuracy of Gaussian fitting for particle size distribution. Overall, the dual cross-linked sericin-pectin beads show potential as mucoadhesive carriers for delivering drugs specifically to the colon. [ABSTRACT FROM AUTHOR]

Sugar beet pulp is a byproduct of white sugar production, and it is quite significant in terms of volume. Every year, tens of millions of tons of beet pulp are produced around the world. However, only a fraction of it is currently used, mainly as animal feed. The composition of beet pulp includes plant polysaccharides, such as cellulose, arabinan, and pectin. Through the process of enzymatic hydrolysis, these polysaccharides are converted into technical C6/C5 sugars, which can be further used as a substrate for the microbial synthesis of various substances, including biofuels, organic acids, and other green chemistry molecules. The current study was designed with a primary objective that focused on the development of a strain that had the potential for enhanced productivity and the capacity to produce enzymes suitable for beet pulp hydrolysis. The pelA and abfA genes, which encode pectin lyase and arabinofuranosidase, respectively, in the fungus Penicillium canescens (VKPM F-178), were cloned and successfully expressed in the recipient strain Penicillium verruculosum B1-537 (VKPM F-3972D). New recombinant strains were created using the expression system of the mycelial fungus P. verruculosum B1-537, which is capable of simultaneously producing pectin lyase and arabinofuranosidase, as well as homologous cellulases. The screening of strains for increased enzymatic activity towards citrus pectin, sugar beet branched arabinan, and microcrystalline cellulose revealed that a B4 clone of P. verruculosum exhibited the greatest potential in sugar beet pulp cake hydrolysis. This clone was selected as the basis for the creation of a new enzyme preparation with enhanced pectin lyase, arabinase, and cellulase activities. The component composition of the enzyme preparation was determined, and the results indicated that the enzyme content comprised approximately 11% pectin lyase, 40% arabinofuranosidase, and 40% cellulases. The primary products of the enzymatic hydrolysis of the unpretreated beet pulp cake were arabinose and glucose. The degree of arabinan and cellulose conversion was observed to be up to 50% and 80%, respectively, after a period of 48 to 72 h of hydrolysis. The new B4 preparation was observed to be highly efficacious in the hydrolysis of beet cake at elevated concentrations of solids (up to 300 g/L) within the reaction mixture. The newly developed strain, as a producer of pectin lyase, arabinofuranosidase, and cellulase complexes, has the potential to be utilized for the bioconversion of sugar beet processing wastes and for the efficient generation of highly concentrated solutions of technical sugars for further implementation in processes of microbial synthesis. [ABSTRACT FROM AUTHOR]

The objective of this study is to investigate the effects of carvacrol on the postharvest storage quality and cell wall metabolism of the 'Guichang' kiwifruit. For this purpose, the 'Guichang' kiwifruit is selected as the test material and treated with 0.03 mg/mL of a carvacrol solution for dipping. The storage quality and cell wall metabolism of the fruit are then evaluated under ambient conditions (20 ± 1 °C). The results indicate that treatment with carvacrol effectively reduces the postharvest respiration rate and weight loss in the kiwifruit, while preserving the levels of vitamin C (VC), soluble protein, total phenols, flavonoids, soluble solids, solid–acid ratio, and soluble pectin. Additionally, it delays the decline in the starch content and mitigates the increase in soluble sugars. Furthermore, carvacrol significantly decreases amylase activity and inhibits the elevation of polygalacturonase (PG), pectin methylesterase (PME), β-galactosidase (β-Gal), and cellulase (Cx) activity. Consequently, this treatment effectively maintains fruit firmness as well as protopectin (PP) and cellulose content at elevated levels. A correlation analysis shows that firmness is highly and negatively correlated with the cell wall degrading enzymes PG, PME, β-Gal, Cx, and α-L-Af, with R values of −0.88, −0.83, −0.98, −0.94, and −0.93, respectively. The negative correlation values for the control group are all lower than 0. In conclusion, treatment with carvacrol effectively preserves a high level of postharvest ripening quality in the kiwifruit, attenuates the metabolic processes of the cell wall, and delays fruit softening and senescence. [ABSTRACT FROM AUTHOR]

Simple Summary: Molybdenum (Mo) is an essential trace element for plant growth and development, and is currently widely used in crop fertilizers. The plant cell wall is the first barrier to prevent the invasion of diseases, and provide protection and support for plant growth. We systematically evaluated the regulatory effects of Mo on tobacco plant growth and cell wall biosynthesis. The application of Mo increased the Mo content, molybdase gene expression, and biomass, and thus promoted tobacco growth. The quantity of C-O-C, -COOH, C-H, and N-H functional groups, and the contents of cellulose, hemicellulose, lignin, protopectin, and soluble pectin were increased in the cell wall of Mo-treated plants. The metabolomics results revealed that Mo could regulate the synthesis of metabolic substances through key metabolic pathways such as galactose metabolism, and arginine and proline biosynthesis. Our findings reveal that Mo has beneficial effects on plant growth and cell wall thickening, and provides important clues for the further investigation of trace elements. Molybdenum (Mo) is widely used as a micronutrient fertilizer to improve plant growth and soil quality. However, the interactions between cell wall biosynthesis and molybdenum have not been explored sufficiently. This study thoroughly investigated the regulatory effects of different concentrations of Mo on tobacco cell wall biosynthesis from physiological and metabolomic aspects. The results indicate that Mo treatment increased the Mo content of tobacco variety K326. Moreover, it significantly up-regulated the gene expression levels of molybdases (NR, AO, SO, XDH) and molybdate transporters in tobacco, whereby the gene expression levels of NR were upregulated by 28.48%, 52.51%, 173.05%, and 246.21%, respectively; and MOT1 and MOT2 were upregulated by 21.49/8.67%, 66.05/30.44%, 93.05/93.26%, and 166.11/114.29%, respectively. Additionally, Mo treatment regulated the synthesis of related enzymes, effectively promoted plant growth, and significantly increased biomass and dry matter accumulation, with the biomass in the leaves increasing significantly by 30.73%, 40.72%, 46.34%, and 12.88%, respectively. The FT-NIR spectroscopy results indicate that after Mo was applied to the soil, the quantity of C-O-C, -COOH, C-H, and N-H functional groups increased. Concurrently, the contents of cellulose, hemicellulose, lignin, protopectin, and soluble pectin in the leaves significantly increased, wherein the content of soluble pectin and hemicellulose increased significantly by 31.01/288.82%, 40.69/343.43%, 69.93/241.73%, and 196.88/223.26%, respectively. Furthermore, the cell walls thickened, increasing the ability of the plant to withstand disturbances. The metabolic network diagrams indicate that Mo regulated galactose metabolism, and arginine and proline acid biosynthesis. The contents of carbohydrates, spermidine, proline, quinic acid, IAA, flavonoids, and other substances were increased, increasing the levels of polysaccharides and pectin within the cell wall, controlling lignin production, and successfully enhancing resistance to abiotic stress. These results offer important perspectives for further investigations into the role of trace elements. [ABSTRACT FROM AUTHOR]

This study examines the impact of titanium and copper ion modifications on the properties of hybrid hydroxyapatite/chitosan granules, which serve as components of novel injectable bone substitutes - biomicroconcretes. In addition to the hybrid granules, the powdered phase of the composites comprises highly reactive α-tricalcium phosphate (α-TCP) powder. The utilization of a mixture consisting of citrus pectin and disodium phosphate as the liquid phase of bone substitutes facilitated the development of easily mouldable, fully injectable biomicroconcretes based on calcium phosphate, characterized by distinct properties. The resulting biomicroconcretes demonstrated favourable cohesion and setting times falling within acceptable parameters. Furthermore, the incorporation of citrus pectin into the liquid phase significantly augmented the mechanical strength of the materials. The unique attributes of biomicroconcretes containing citrus pectin arise from the presence of both a dual setting system and a double hybrid system. The dual setting mechanism, stemming from the hydrolysis of α-TCP and the crosslinking of citrus pectin in the presence of Ca2⁺ ions, yielded materials distinguished by excellent cohesion and chemical stability. Conversely, the double hybrid system emerged from the coexistence of hybrid granules and interactions between polycationic chitosan within the hybrid granules and polyanionic citrus pectin. All obtained biomicroconcretes exhibited in vitro bioactivity, positioning them as promising candidates for further biological investigations. Notably, the integration of antibacterial copper ions into hybrid hydroxyapatite/chitosan granules significantly enhances their potential utility as bone substitute materials, effectively reducing the risk of S. aureus and E. coli infection during surgical procedures. It has been found that titanium modified composites reduced adhesion of S. aureus but did not reduce the adhesion of E. coli cells. This research validates the advantageous properties of the synthesized ceramic-based biomaterials and sets the stage for subsequent in vitro and in vivo studies. [ABSTRACT FROM AUTHOR]

In response to the restrictions imposed by their epiphytic habit, orchids have developed structural traits that allow greater efficiency in water uptake and use, such as a complex adventitious root system with velamen. The composition of cell wall of this specialized epidermis can be altered according to the substrate to which it is fixed, influencing wall permeability, absorption, and storage of water in roots. The current study aimed to evaluate the cell wall composition of adventitious roots of Vanilla phaeantha (Orchidaceae) that grow attached to the phorophyte, fixed in the soil, or hung free. Immunocytochemical analyses were used to determine the protein, hemicellulose, and pectin composition of the cell walls of aerial and terrestrial roots. We observed that pectins are present in the different tissues of the aerial roots, while in the terrestrial roots, they are concentrated in the cortical parenchyma. The deposition of xyloglucans, extensins, and arabinogalactans was greater in the epidermis of the free side of the roots attached to the phorophyte. The strong labeling of pectins in aerial roots may be related to the influx of water and nutrients, which are generally scarce in this environment. The arrangement of hemicelluloses and proteins with the pectins may be associated with increased cell rigidity and sustainability, a feature of interest for the aerial roots. In summary, the habit of roots can interfere with the non-cellulosic composition of the cell walls of V. phaeantha, possibly related to changes in cell functionality. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the effect of the recommended (6.5 mg/kg) or enhanced (13 mg/kg) level of CuNPs in the diet in combination with different types of dietary fibre – cellulose (control), inulin, pectin, or psyllium on the Cu biodistribution and level of selected minerals parameters in the blood of rats. Rats were randomly divided into 10 groups. The first two groups were fed control diets containing cellulose and a mineral mixture with standard or enhanced content of CuCO3. Experimental groups were fed a diet supplemented with CuNPs (6.5 or 13 mg/kg) and combined with different types of fibre (cellulose, pectin, inulin, or psyllium). After the feeding period blood, liver, brain, and thigh samples were collected. In the samples of water, diet, urine, faeces, liver, brain, and thigh the Cu content was determined to assess Cu biodistribution in the body. Additionally, the concentrations of minerals (Cu, P, Ca, Mg, Fe, and Zn) in the blood plasma samples were measured. The replacement of CuCO3 with CuNPs in the diet beneficially influenced the biodistribution of Cu in the body by reducing its excretion, improving its digestibility, and utilization, reducing its accumulation in the brain and muscle, and increasing levels of Ca, P, Mg, Zn and Fe in the blood. Increasing the level of CuNPs in the diet increased total Cu intake. The addition of pectin, inulin and psyllium to the diet with a high content of CuNPs significantly increased the excretion of Cu, with no negative effect on its digestibility, and utilization, and prevented its excessive accumulation in the brain and muscle of rats, especially in the case of inulin. The results suggest that the addition of dietary fibre to the diet of rats ensures homeostasis of this element in the case of excessive intake of CuNPs by modifying the bioavailability of Cu. [ABSTRACT FROM AUTHOR]

Although angiosperm plants generally react to immunity elicitors like chitin or chitosan by the cell wall callose deposition, this response in particular cell types, especially upon chitosan treatment, is not fully understood. Here we show that the growing root hairs (RHs) of Arabidopsis can respond to a mild (0.001%) chitosan treatment by the callose deposition and by a deceleration of the RH growth. We demonstrate that the glucan synthase‐like 5/PMR4 is vital for chitosan‐induced callose deposition but not for RH growth inhibition. Upon the higher chitosan concentration (0.01%) treatment, RHs do not deposit callose, while growth inhibition is prominent. To understand the molecular and cellular mechanisms underpinning the responses to two chitosan treatments, we analysed early Ca2+ and defence‐related signalling, gene expression, cell wall and RH cellular endomembrane modifications. Chitosan‐induced callose deposition is also present in the several other plant species, including functionally analogous and evolutionarily only distantly related RH‐like structures such as rhizoids of bryophytes. Our results point to the RH callose deposition as a conserved strategy of soil‐anchoring plant cells to cope with mild biotic stress. However, high chitosan concentration prominently disturbs RH intracellular dynamics, tip‐localised endomembrane compartments, growth and viability, precluding callose deposition. Summary statement: The root hairs (RHs) of Arabidopsis, when exposed to elicitor chitosan, deposit callose and change the growth rate. This is accompanied by altered signalling, gene expression, and is linked to altered pectin methylation state. Our research highlights the evolutionarily conserved role of RHs in environmental sensing. [ABSTRACT FROM AUTHOR]

Fruit waste (FW), mainly from agroindustry, is currently left behind in landfills despite its rich composition. The bioactive compounds (e.g., oils, polyphenols), carbohydrates, and lignin present in this biomass type require comprehensive characterization (i.e., identification and quantification) before they can be used as raw materials in biorefineries. This review collected information from scientific papers on FW compositional analysis methods and characterization data; the information needs to be compiled in a systematic, standardized, and comprehensive way to understand and quantify the true potential of FW as feedstocks for biorefineries. The information gathered in this review allowed us to identify the biomass fractions that could be valorized further depending on the kind of FW (peels, seeds, or seed vessels, and pomace or mixed residues). Fruit waste differs from conventional lignocellulosic biomass due to the presence of higher amounts (>5%) of extractives – pectin, and starch. This review describes current compositional analysis methodologies to identify possible strengths and weaknesses that could affect the adequate selection of valorization platforms. As no current methodology allows the composition of FW to be described thoroughly, this work identifies procedures applicable to biorefineries that use FW. Possible improvements are suggested to fill methodological gaps in the quantification of samples with large amounts of extractives and pectin. The standardization of methods for FW's quantification is fundamental for the adequate integration of different valorization platforms into biorefineries. It is essential to consider all the substances present in FW to exploit fully their potential for new value‐added molecules, including oils, polyphenols, and pectin. [ABSTRACT FROM AUTHOR]

Pectin is widely spread in nature and it develops an extremely complex structure in terms of monosaccharide composition, glycosidic linkage types, and non-glycosidic substituents. As a non-digestible polysaccharide, pectin exhibits resistance to human digestive enzymes, however, it is easily utilized by gut microbiota in the large intestine. Currently, pectin has been exploited as a novel functional component with numerous physiological benefits, and it shows a promising prospect in promoting human health. In this review, we introduce the regulatory effects of pectin on intestinal inflammation and metabolic syndromes. Subsequently, the digestive behavior of pectin in the upper gastrointestinal tract is summarized, and then it will be focused on pectin's fermentation characteristics in the large intestine. The fermentation selectivity of pectin by gut bacteria and the effects of pectin structure on intestinal microecology were discussed to highlight the interaction between pectin and bacterial community. Meanwhile, we also offer information on how gut bacteria orchestrate enzymes to degrade pectin. All of these findings provide insights into pectin digestion and advance the application of pectin in human health. [ABSTRACT FROM AUTHOR]

[Objective] In order to provide technical support for further improving the aging quality of core tobacco raw materials, the suitable packing densities for natural aging of different grades of tobacco leaves were explored. [Method] Hongda B2F, C3F and X2F redried strips were selected as test materials, and the packing density of each redried strips was set with 4 gradients, namely 180,190,200 and 210 kg/carton (0.514 m³). The effects of different packing densities on the contents of aroma components, cellulose, lignin, pectin, plastid pigment and sensory quality of aged strips were analyzed after the above redried strips were aged for 600 d under the same storage environment.[Result]The contents of some chemical components and sensory quality showed great differences after the same redried strips were naturally aged for 2 years with different packing densities. Comprehensively compare the differences of aroma components, cellulose, lignin, pectin, plastid pigments and sensory quality of aged strips with different packing densities, the suitable packing density of B2F,C3F and X2F redried strips was 200,180 and 190 kg/carton respectively.[Conclusion]The packing density of redried strips had a great impact on its aging effect, and different packing densities were suitable for aging of different grades of redried strips. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) is a subject of interest for researchers due to its advantageous characteristics, including a straightforward manufacturing process, biocompatibility, and extensive modification potential. The hydrophilic nature of the material is beneficial in some applications, yet a limiting factor in others. This study aimed to develop BC-based materials with goFogureod moisture resistance. The modification of bacterial cellulose (BC) using apple powder, stearic acid, or a combination of these modifiers resulted in the formation of a range of materials, some of which had their surfaces additionally functionalised by coating with a mixture of apple powder and stearic acid (HSt). The nature and type of changes were confirmed by FTIR and theoretical analysis, which was conducted by modelling the interaction between cellulose and homogalacturonan or rhamnogalacturonan using SCIGRESS v.FJ 2.7 software. Changes in hydrogen bonding resulting in a weakening of the interactions between cellulose and water in the presence of pectin were demonstrated by both empirical data and modelling. The effectiveness of BC functionalisation was confirmed by material wettability. The water contact angle changed from 38° for the unmodified material to 125° for the material obtained by modification of the bacterial cellulose with glycerol followed by modification with a mixture of HSt at a concentration of 10% and AP at a concentration of 60%. The modifications produced a material with a robust hydrophobic surface. The results suggest that the surface roughness may not be the primary factor influencing the hydrophilicity or hydrophobicity of these materials but that it is more likely to be related to the interactions of components. None of the tested materials demonstrated antimicrobial activity against Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Aspergillus niger, or Candida albicans. [ABSTRACT FROM AUTHOR]

Objective: А method has been developed for extracting modified pectin from plant raw materials by using microwave radiation at the stage of washing. Methods: The rheological properties of 5.0% aqueous solutions of apple pectin obtained by exposure to microwave radiation of various powers: 300, 450 and 600 W, as well as pectins obtained by the traditional method at temperatures of 25, 40, 55, 70°C were investigated. Results and Discussion: It is shown that the use of microwave radiation can improve the method of obtaining pectins by increasing the yield of pectins and regulating their structure and properties. The rheological properties of concentrated aqueous solutions of pectins obtained by exposure to microwave radiation of various powers have been studied. It is shown that all studied systems of pectin solutions are non-Newtonian fluids with a pseudoplastic type of viscous flow anomaly, determined by the values of the microwave energy. The values of the apparent activation energies of the viscous flow of solutions, which are an indirect characteristic of the strength of the structures of the system, have been estimated. Data was obtained on the structure and changes in the structure of their concentrated solutions under the action of external forces and temperature in the course of a viscous flow. Conclusions: It is shown that the power values оf microwave radiation are the main factor determining the structure of molecular matrices of pectins and the structure of their concentrated aqueous solutions. [ABSTRACT FROM AUTHOR]

Background and Aims The cell walls of charophytic algae both resemble and differ from those of land plants. Cell walls in early-diverging charophytes (e.g. Klebsormidiophyceae) are particularly distinctive in ways that might enable survival in environments that are incompatible with land-plant polymers. This study therefore investigates the structure of Klebsormidium polysaccharides. Methods The 'pectin' fraction (defined by extractability) of Klebsormidium fluitans , solubilized by various buffers from alcohol-insoluble residues, was digested with several treatments that (partly) hydrolyse land-plant cell-wall polysaccharides. Products were analysed by gel-permeation and thin-layer chromatography. Key Results The Klebsormidium pectic fraction made up ~30–50 % of its alcohol-insoluble residue, was optimally solubilized at pH 3–4 at 100 °C, and contained residues of xylose ≈ galactose > rhamnose > arabinose, fucose, mannose and glucose. Uronic acids were undetectable, and the pectic fraction was more readily solubilized by formate than by oxalate, suggesting a lack of chelation. Some land-plant-targeting hydrolases degraded the Klebsormidium pectic fraction: digestion by α- l -arabinanase, endo-β-(1→4)- d -xylanase and α- d -galactosidase suggests the presence of β-(1→4)-xylan with terminal α- l -arabinose, α- d -galactose and (unexpectedly) rhamnose. 'Driselase' released oligosaccharides of xylose and rhamnose (~1:1), and graded acid hydrolysis of these oligosaccharides indicated a 'rhamnoxylan' with rhamnose side-chains. Partial acid hydrolysis of Klebsormidium pectic fraction released rhamnose plus numerous oligosaccharides, one of which comprised xylose and galactose (~1:2 Gal/Xyl), suggesting a galactoxylan. Lichenase was ineffective, as were endo-β-(1→4)- d -galactanase, endo-β-(1→4)- d -mannanase, β- d -xylosidase and β- d -galactosidase. Conclusions Klebsormidium pectic fraction possesses many land-plant-like linkages but is unusual in lacking uronic acid residues and in containing rhamnoxylan and galactoxylan domains. Uronic acids allow land-plant and late-diverging charophyte pectins to form Ca2+-bridges, facilitating cell-wall polymer association; their absence from Klebsormidium suggests that neutral heteroxylans rely on alternative cross-linking mechanisms. This lack of dependence on Ca2+-bridges might confer on Klebsormidium the ability to grow in the acidic, metal-rich environments that it tolerates. [ABSTRACT FROM AUTHOR]

SUMMARY The plant cell wall is the first barrier against pathogen invasion. Fusarium solani is the primary pathogen responsible for apple replant disease. In this study, we identified an MYB protein, MdMYB54, which interacts with the positive regulator of F. solani resistance, MdERF114, and confers apple‐increased tolerance against F. solani. The cellulose synthetase (CESA) gene MdCesA6 and pectin lyase‐like (PLL) genes MdPLL8 and MdPLL12 were screened as three potential downstream target genes of MdMYB54 using DAP‐seq. The results of electrophoretic mobility shift and yeast one‐hybrid assays showed that MdMYB54 directly binds to the promoters of MdCesA6, MdPLL8, and MdPLL12 in vivo and in vitro. Dual‐luciferase and β‐glucuronidase assays showed that MdMYB54 activates the expression of these genes. The cellulose content and pectin lyase activity of MdMYB54‐overexpressed roots were significantly higher than those of wild‐type plants under F. solani treatment but were the opposite in MdMYB54‐RNAi roots. The deposition of cellulose enhanced the physical barrier of the plant cell wall, whereas the activation of pectin lyase promoted the formation of oligogalacturonides and the production of reactive oxygen species. Overexpression of MdCesA6, MdPLL8, and MdPLL12 in the root system enhanced the tolerance of apple to F. solani. The direct interaction of MdERF114 with MdMYB54 enhanced MdMYB54‐mediated cell wall defense response. These results suggest that modifying these candidate genes may provide a strategy for improving the resistance of apple to F. solani. [ABSTRACT FROM AUTHOR]

AbstractPectin, a complex dietary fiber, constitutes a key structural component of the cell walls of numerous edible plant products. It is resistant to digestion by human enzymes and undergoes depolymerization and saccharification in the gastrointestinal tract through the action of carbohydrate-active enzymes (CAZymes) produced by gut microbiota. This enzymatic breakdown generates intermediate structural fragments, which are subsequently converted into pectin oligosaccharides (POS) and monosaccharides. POS exhibit prebiotic properties and have demonstrated potential health benefits, including anti-carcinogenic effects, mucoadhesive capabilities, and the promotion of beneficial gut bacterial growth. However, the current understanding of the molecular structure of pectin and its degradation dynamics remains fragmented within the literature, impeding progress in dietary fiber intervention research and the development of personalized nutrition approaches. This review aims to provide a comprehensive overview of the structural features of pectin and the intricate breakdown mechanisms orchestrated by CAZymes. It underscores the complex architecture of pectin that influences its breakdown dynamics and specifies the enzymatic requirements for the cleavage of its diverse structural components. These insights complement our accompanying review on the structure-function relationships between pectin and the human gut microbiota, previously published in this journal. [ABSTRACT FROM AUTHOR]

Citrus peels are produced in large quantities as a by-product of beverage production, leading to underutilization of waste. Sitaya agrihorti citrus is one of the citrus varieties used in the beverage industry because of its sweet taste. Wasted sitaya citrus peels contain components such as pectin. Microwaveassisted extraction (MAE) is a well-known innovative method, currently widely used in pectin extraction due to its efficiency and reduced processing time compared to conventional methods. This study used MAE at different power levels: 360, 450, 540, 630, and 720W, each applied for two minutes. The extracted pectin was evaluated for key properties, including equivalent weight, methoxyl content, galacturonic acid content, degree of esterification, and water content. This study aims to determine the effect of microwave power on pectin yield and quality. The results showed that microwave power significantly affected pectin yield (p < 0.01), with the highest yield of 12.103% obtained at 720W power. However, variations in microwave power did not significantly affect the physical or chemical characteristics of pectin extracted from Sitaya citrus peel. This study concluded that MAE is an effective extraction method for producing pectin from citrus peel waste, which offers a sustainable approach to agro-industrial waste management. The findings highlight the potential for increasing the value of orange peel through an efficient extraction process, contributing to economic and environmental sustainability while creating value-added products. [ABSTRACT FROM AUTHOR]

The study is designed to investigate the protein composition of pectin-based edible films, with a particular emphasis on those films that have been enhanced by the incorporation of Spirulina powder. To assess the impact of Spirulina powder on pectin-based edible films, a comparative study was conducted. The control group featured pectin content at 20%, while the experimental group comprised pectin (20%) with varying concentrations of Spirulina powder (5%, 10%, 15%). The sample size determination utilized clincalc.com, establishing parameters of 80% power, a 0.05 significance level, and a 95% confidence level. Each group consisted of 20 samples, resulting in a total sample size of 40. The results indicate a noteworthy difference in protein content between the control and experimental groups. Specifically, the control group exhibited a lower protein content at 4.46 g/100 g, while the experimental group, particularly the subset enriched with 15% Spirulina powder, demonstrated a significantly higher protein content of 56.47 g/100 g. The statistical analysis confirmed the significance of these findings, with a p-value of less than 0.05. Edible films with elevated protein content can be used as carriers for functional ingredients, turning them into a vehicle for delivering bioactive compounds. This opens up possibilities for developing functional foods with added health benefits. [ABSTRACT FROM AUTHOR]

In this project, the in‐situ formation of magnetic nanoparticles modified with pectin and acetamide was presented and used as a sorbent in the magnetic solid‐phase extraction method. The synthesis of the magnetic sorbent was studied by various characterization methods. The sorbent was employed for the microextraction of four model analytes including methyl paraben, ethyl paraben, propyl paraben, and butyl paraben. The separation and measurement of the extracted compounds were done by high‐performance liquid chromatography‐ultraviolet detection. In order to achieve the best extraction condition, factors affecting the extraction efficiency were investigated and optimized using response surface methodology. In the obtained optimized condition, the following parameters were achieved: limits of detection: 0.16–0.28 µg/L, limits of quantification: 0.49–0.92 µg/L, and intra‐ and inter‐day relative standard deviations: 1.2%–6.6% and 1.6%–4.8%, respectively. The linear dynamic ranges of the method for methyl paraben, ethyl paraben, butyl paraben, and propyl paraben were 1–200, 0.5–500, 1–500, and 1–500 µg/L, respectively. In order to investigate the effectiveness of the method, the proposed magnetic nanosorbent was used to measure the desired parabens in cosmetic samples. The results showed good accuracy and precision of the developed method for the determination of trace amounts of target analytes. [ABSTRACT FROM AUTHOR]

Extraction of organic and bioactive compounds from plant materials with the traditional organic solvents aided by water or oil bath heating is not sustainable, because it consumes a lot of energy, time, water/oil, solvents, and results in lower yield. This review discusses deep eutectic solvent (DES) as a green solvent, physical field technology (PFT) as a water‐saving and green technology, and how the coupling of PFT (ultrasound [US], microwave [MW], infrared [IR]) to DES will improve the yield and quality of protein, polysaccharides, polyphenols, pectin, and terpenoids extracted from plant materials. Ultrasonication increases DES extraction efficiency via cavitation dislodgement and pores creation. IR coupling to DES enhances the extraction yield of polyphenols and the antioxidant and antiradical activity. MW improves DES extraction yield, reduces energy consumption, operational cost, and compound degradation, and is inferred to be the greenest technology. [ABSTRACT FROM AUTHOR]

Summary: Softening in fruit adversely impacts their edible quality and commercial value, leading to substantial economic losses during fruit ripening, long‐term storage, long‐distance transportation, and marketing. As the apple fruit demonstrates climacteric respiration, its firmness decreases with increasing ethylene release rate during fruit ripening and postharvest storage. However, the molecular mechanisms underlying ethylene‐mediated regulation of fruit softening in apple remain poorly understood. In this study, we identified a WRKY transcription factor (TF) MdWRKY31, which is repressed by ethylene treatment. Using transgenic approaches, we found that overexpression of MdWRKY31 delays softening by negatively regulating xyloglucan endotransglucosylase/hydrolases 2 (MdXTH2) expression. Yeast one‐hybrid (Y1H), electrophoretic mobility shift (EMSA), and dual‐luciferase assays further suggested that MdWRKY31 directly binds to the MdXTH2 promoter via a W‐box element and represses its transcription. Transient overexpression of ethylene‐induced MdNAC7, a NAC TF, in apple fruit promoted softening by decreasing cellulose content and increasing water‐soluble pectin content in fruit. MdNAC7 interacted with MdWRKY31 to form a protein complex, and their interaction decreased the transcriptional repression of MdWRKY31 on MdXTH2. Furthermore, MdNAC7 does not directly regulate MdXTH2 expression, but the protein complex formed with MdWRKY31 hinders MdWRKY31 from binding to the promoter of MdXTH2. Our findings underscore the significance of the regulatory complex NAC7–WRKY31 in ethylene‐responsive signalling, connecting the ethylene signal to XTH2 expression to promote fruit softening. This sheds light on the intricate mechanisms governing apple fruit firmness and opens avenues for enhancing fruit quality and reducing economic losses associated with softening. [ABSTRACT FROM AUTHOR]

Pectin was extracted from onion peels using microwave and ultrasound-assisted natural deep eutectic solvents (NADES) and compared with conventional acid-extracted pectin. The primary screening trials indicated that the suitable combination of hydrogen bond acceptor and donor was choline chloride and tartaric acid, respectively. The Box-Behnken design was further used to optimize processing conditions like microwave intensity (26.903 W/g), microwave processing duration (2.99 min), and sonication duration (10.18 min) for maximizing the pectin yield from onion peel powder. The moisture, ash, and equivalent weight of extracted pectin were in the range specified by the International Pectin Producers Association. The higher anhydrouronic acid content of the NADES-extracted pectin indicated the higher purity of pectin compared to the conventional acid-extracted pectin. The NADES-based extraction was found to be a promising system for extracting pectin with a higher degree of esterification from onion peels. [ABSTRACT FROM AUTHOR]

SUMMARY: Cotton fiber is the most valuable naturally available material for the textile industry and the fiber length and strength are key determinants of its quality. Dynamic changes in the pectin, xyloglucan, xylan, and cellulose polysaccharide epitope content during fiber growth contribute to complex remodeling of fiber cell wall (CW) and quality. Detailed knowledge about polysaccharide compositional and structural alteration in the fiber during fiber elongation and strengthening is important to understand the molecular dynamics of fiber development and improve its quality. Here, large‐scale glycome profiling coupled with fiber phenotype and transcriptome profiling was conducted on fiber collected daily covering the most critical window of fiber development. The profiling studies with high temporal resolution allowed us to identify specific polysaccharide epitopes associated with distinct fiber phenotypes that might contribute to fiber quality. This study revealed the critical role of highly branched RG‐I pectin epitopes such as β‐1,4‐linked‐galactans, β‐1,6‐linked‐galactans, and arabinogalactans, in addition to earlier reported homogalacturonans and xyloglucans in the formation of cotton fiber middle lamella and contributing to fiber plasticity and elongation. We also propose the essential role of heteroxylans (Xyl‐MeGlcA and Xyl‐3Ar), as a guiding factor for secondary CW cellulose microfibril arrangement, thus contributing to fiber strength. Correlation analysis of profiles of polysaccharide epitopes from glycome data and expression profiles of glycosyltransferase‐encoding genes from transcriptome data identified several key putative glycosyltransferases that are potentially involved in synthesizing the critical polysaccharide epitopes. The findings of this study provide a foundation to identify molecular factors that dictate important fiber traits. Significance Statement: This multi‐profiling study with high‐temporal resolution discovered the essential role of specific RG‐I pectin epitopes, homogalacturonans, and xyloglucans in contributing to fiber elongation and the critical role of two heteroxylans in secondary CW cellulose‐microfibril arrangement, thus contributing to fiber strength. The key glycosyltransferase enzymes synthesizing these polysaccharide epitopes were also identified. The additional molecular details discovered here could be a valuable foundational source for future research to improve the fiber quality and its commercial value. [ABSTRACT FROM AUTHOR]

To control mango postharvest deterioration, an edible coating based on pectin, glycerol, and oregano essential oil (OEO) was developed using a three‐step process involving optimization, validation, and comparison with a commercial fungicide. An extreme vertices mixture design approach was initially used to optimize the pectin, glycerol, and OEO concentrations in the coating formulation. We evaluated the impact of the coating components on the respiration rate, quality parameters, and anthracnose disease of mangoes. The optimal coating composition was 3.91% (w/v) pectin, 0.57% (w/v) glycerol, and 0.52% (w/v) OEO, with a desirability value of 0.8998. Model validation demonstrated that the measured values for all parameters fit the prediction interval of 95%, and the relative error varied between 0.88% and 12.28%. Validation experiments of the optimal coating compared to untreated mango and mango treated with a commercial fungicide showed that the optimal coating delayed ripening and effectively controlled the incidence of anthracnose for 18 days at 14°C and 85% relative humidity. [ABSTRACT FROM AUTHOR]

Pectin, a complex polysaccharide found abundantly in the cell walls of fruits and vegetables, plays a pivotal role in various food applications owing to its unique gelling, thickening and stabilizing properties. As consumer preferences lean towards natural and sustainable ingredients, the demand for pectin as a food additive has surged. This burgeoning interest has prompted a comprehensive exploration into both the extraction methods of pectin from its natural sources and its diverse technological applications in the food industry. The extraction process involves breaking down the plant cell wall to release the pectin. Traditional methods such as hot acid extraction have been widely used, but advances in technology have spurred the development of novel techniques like enzyme‐assisted extraction and microwave‐assisted extraction. These methods aim not only to enhance the yield and purity of extracted pectin but also to minimize environmental impact and energy consumption. Pectin's versatility has positioned it as a valuable ingredient in the food industry. Its ability to form gels under specific conditions makes it a key component in the production of jams, jellies and fruit preserves. Additionally, pectin acts as a stabilizer in dairy products, prevents syneresis in baked goods and improves the texture of confectionery items. The application of pectin goes beyond its role as a gelling agent; it is also employed in the encapsulation of bioactive compounds, enhancing the functional properties of various food products. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Teredinibacter turnerae is a cultivable cellulolytic Gammaproteobacterium (Cellvibrionaceae) that commonly occurs as an intracellular endosymbiont in the gills of wood‐eating bivalves of the family Teredinidae (shipworms). The genome of T. turnerae encodes a broad range of enzymes that deconstruct cellulose, hemicellulose and pectin and contribute to wood (lignocellulose) digestion in the shipworm gut. However, the mechanisms by which T. turnerae secretes lignocellulolytic enzymes are incompletely understood. Here, we show that T. turnerae cultures grown on carboxymethyl cellulose (CMC) produce membrane vesicles (MVs) that include a variety of proteins identified by liquid chromatography–mass spectrometry (LC–MS/MS) as carbohydrate‐active enzymes (CAZymes) with predicted activities against cellulose, hemicellulose and pectin. Reducing sugar assays and zymography confirm that these MVs exhibit cellulolytic activity, as evidenced by the hydrolysis of CMC. Additionally, these MVs were enriched with TonB‐dependent receptors, which are essential to carbohydrate and iron acquisition by free‐living bacteria. These observations indicate a potential role for MVs in lignocellulose utilisation by T. turnerae in the free‐living state, suggest possible mechanisms for host–symbiont interaction and may be informative for commercial applications such as enzyme production and lignocellulosic biomass conversion. [ABSTRACT FROM AUTHOR]

Summary: Black mulberry extract (BME) is rich in phenolics; however, their health benefits are restricted by their instability and poor absorption in the small intestine. Liposomal BME‐loaded pullulan/pectin nanofibers were developed to enhance the in vitro bioaccessibility of BME. The liposomes with BME (0.8%, w/v), were produced by the thin‐film hydration and ultrasonication method with a size of 76.41 ± 1.23 nm and encapsulated 79.40 ± 0.99%.of the BME. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) images showed that the uniform distribution of liposomes within the defect‐free fiber structure. Liposomal BME loading elevated the mucoadhesiveness of the nanofibers compared to free BME loading. Liposomal BME‐loaded nanofiber demonstrated a nearly two‐fold increase in the bioaccessibility of anthocyanins. The cellular release of all four different anthocyanins by Caco‐2 cells was significantly higher (3.92%–10.50%) in liposomal BME‐loaded nanofiber. Therefore, liposomal nanofibers show great potential as a method for delivering phenolics, specifically anthocyanins. [ABSTRACT FROM AUTHOR]

Superabsorbent polymers (PSAs) have been extensively studied to act as internal curing agents in cementitious materials, as they have the characteristic of absorbing and releasing water in a controlled manner, which can contribute to the hydration process of a cementitious medium during its consolidation. Thus, hydrogels consisting of polyacrylamide (PAAm), pectin (Pec) and rice husk ash (RHA) were synthesized to be applied in cementitious matrices. In addition, the PSAs were characterized by FTIR, SEM, and XRD. For evaluating the usage of hydrogels as internal curing agents, different hydrogel contents—0.03, 0.06, and 0.1 (wt-%, relative to cementitious components)—were used for mortar preparation. The mechanical strengths of the cementitious materials were evaluated at day 7 and day 28 during the curing process. The addition of PSAs to the mortars caused an increase in mechanical resistance such that the 0.06% content presented better performance at day 7 of curing (4.07% higher) and at day 28 of curing (8.06% higher) when compared with the reference mortar (without the addition of PSAs) in the same curing periods. This work demonstrates that the addition of PSAs contributes to the hydration of a cementitious material, improving the mechanical resistance of the studied mortars. [ABSTRACT FROM AUTHOR]

The Chinese chestnut (Castanea mollissima Blume) is a dioecious plant in which the number of male inflorescences far exceeds that of female inflorescences. Therefore, it is of interest to study the differentiation of male flowers in C. mollissima. In this study, the male inflorescences of "Yanshanhongli" C. mollissima were observed. Then, the main components of the cell wall were stained by fluorescence and immunofluorescence labeling techniques to examine the changes in cell wall components. The results showed that the development of the male inflorescence of C. mollissima had different transverse elongation and longitudinal elongation. In addition, the development of male inflorescences and anthers were divided into five and four major stages, respectively, according to the microstructural changes. Immunostaining indicated that the fluorescence intensity of cellulose increased with the development of male inflorescences of C. mollissima. The fluorescence intensity of low-esterified homogalacturonan (HG) was stronger in the early stage, while the fluorescence intensity of high-esterified HG was stronger thereafter. This research provides new insights into the changes in cell wall components during the growth and development of male inflorescences of C. mollissima and important clues for exploring the growth and development mechanism of male inflorescences of C. mollissima. [ABSTRACT FROM AUTHOR]

Liparis loeselii (L.) Rich, an endangered member of the Orchidaceae family, is found in alkaline fens. With the declining populations of L. loeselii, there is a pressing need to reintroduce this species in Central Europe. As in vitro germination is a crucial tool for obtaining plants for introduction into the environment, we looked at the morphological changes occurring during the early stages of L. loeselii development in vitro. As the early stages of orchid development, especially the protocorm stage, are thought to be responsible for SAM formation and the initiation of symbiotic association, we focused on cell wall elements whose epitopes have been found in similar processes in other species: the extensin and pectin rhamnogalacturonan I (RG-I) side chain epitopes. We addressed the following questions: Does the cell wall of L. loeselii change its composition during the early stages of development, as noted in other species? Are there noticeable similarities in the cell wall to organs of different species whose function is to contact microorganisms? Are there regularities that allow the recognition of individual structures on this basis? Immunolocalization revealed changes in the distribution of certain extensins (JIM11 and JIM20) and RG-I (LM5 and LM6) side chain epitopes. Extensins, a type of cell wall protein, were observed during the initial stages of the formation of PLB and the shoot apical meristem of protocorms and PLBs. RG-I, on the other hand, was found to play a significant role in the development of the protocorm and PLB. In pseudobulbs, which appeared on the protocorms, extensins occurred in their storage part. However, RG-I side chains (1→4)-β-galactans (LM5), and (1→5)-α-L-arabinans (LM6) were not found in pseudobulbs. We revealed that a common feature of protocorms and PLBs was an increased amount of extensins, which were detected with the JIM11 antibody, and pectins, which were detected with the LM5 antibody, that were present together, which may prove helpful in determining the identity of the induced structures and distinguishing them from pseudobulbs. Thus, our study unveiled the role of extensins and RG-I during the growth of protocorms and PLBs. We suggest that PLBs may mimic the wall remodelling that occurs in protocorms, which indicates that using cell wall components is an invitation to be colonised by a fungal partner. However, this needs to be tested in future research. The findings of this research can help interpret future studies on the propagation, acclimatisation, and introduction of L. loeselii into the natural environment. [ABSTRACT FROM AUTHOR]

We investigate the effect of pectin on the structure and ion transport properties of the room-temperature ionic liquid electrolyte 1-n-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) using molecular dynamics simulations. We find that pectin induces intriguing structural changes in the electrolyte that disrupt large ionic aggregates and promote the formation of smaller ionic clusters, which is a promising finding for ionic conductivity. Due to pectin in [BMIM][PF6] electrolytes, the diffusion coefficient of cations and anions is observed to decrease by a factor of four for a loading of 25 wt. % of pectin in [BMIM][PF6] electrolyte. A strong correlation between the ionic diffusivities (D) and ion-pair relaxation timescales (τc) is observed such that D ∼ τc−0.75 for cations and D ∼ τc−0.82 for anions. The relaxation timescale exponents indicate that the ion transport mechanisms in pectin-[BMIM][PF6] electrolytes are slightly distinct from those found in neat [BMIM][PF6] electrolytes (D ∼ τ c − 1 ). Since pectin marginally affects ionic diffusivities at the gain of smaller ionic aggregates and viscosity, our results suggest that pectin-ionic liquid electrolytes offer improved properties for battery applications, including ionic conductivity, mechanical stability, and biodegradability. [ABSTRACT FROM AUTHOR]

Using waste such as prickly pear (Opuntia lasiacantha P.) peel to obtain value-added compounds such as pectin is possible with emerging technologies. This study used the Taguchi optimization model to maximize the extraction of chelating-soluble pectin (CSP) through an ohmic heating (OH) process. The maximum pectin yield obtained was 3.32% under the best processing conditions, and the galacturonic acid content was 726.26 mg/g, as well as a range of pectin with a low degree of esterification. The electric field and sodium hexametaphosphate concentration significantly affected the quality and yield of CSP. Additionally, the flow of electrical current during pectin extraction was governed by the concentration of added sodium hexametaphosphate (SHMP), which acted as an electrolyte and chelating agent for CSP. The use of OH in the recovery of CSP from red prickly pear with potential application and care of the proportions of GalA and %yield is presented as an effective option for the recovery of value-added additives from agro-industrial waste. [ABSTRACT FROM AUTHOR]

Pectin is a valuable polysaccharide used in the food industry as a gelling, stabilizing, and emulsifying agent. It is one of the main components found in fruits and vegetables; however, it is mostly disposed of as waste during their processing. This study aims to optimize the extraction conditions of pectin from black carrot pomace by microwave-assisted high-pressure CO2/H2O method. This novel technique is based on the use of a combination of microwave with pressurized CO2 in water to increase extraction yield and produce high-quality pectin. The effects of temperature (95–130 °C), time (2–12 min), and liquid/solid ratio (15–30 ml/g) on pectin yield were examined by using RSM. Optimum conditions obtained for microwave-assisted high-pressure CO2/H2O extraction were 130 °C of temperature, 2.0 min of extraction time, and 22.5:1 ml/g of liquid-to-solid ratio, which yielded a pectin recovery of 28.4%. The use of microwave-assisted high-pressure CO2/H2O extraction technique allowed 45% higher pectin recovery and about 97% time saving compared to the conventional acid hydrolysis method using acidified water (0.1 N HCl) (yield 19.55% and time 90 min). Pectin extracted by microwave-assisted high-pressure CO2/H2O was found to possess better characteristics compared to conventionally extracted pectin in terms of composition and physical, chemical, emulsion, and flow properties. [ABSTRACT FROM AUTHOR]

Land plants evolved from an ancestral alga around 470 mya, evolving complex multicellularity in both haploid gametophyte and diploid sporophyte generations. The evolution of water-conducting tissues in the sporophyte generation was crucial for the success of land plants, paving the way for the colonization of a variety of terrestrial habitats. Class II KNOX (KNOX2) genes are major regulators of secondary cell wall formation and seed mucilage (pectin) deposition in flowering plants. Here, we show that, in the liverwort Marchantia polymorpha , loss-of-function alleles of the KNOX2 ortholog, Mp KNOX2 , or its dimerization partner, Mp BELL1 , have defects in capsule wall secondary cell wall and spore pectin biosynthesis. Both genes are expressed in the gametophytic calyptra surrounding the sporophyte and exert maternal effects, suggesting intergenerational regulation from the maternal gametophyte to the sporophytic embryo. These findings also suggest the presence of a secondary wall genetic program in the non-vascular liverwort capsule wall, with attributes of secondary walls in vascular tissues. [Display omitted] • Marchantia Class II KNOX is maternally expressed in the calyptra post-fertilization • Mp KNOX2 non-cell autonomously directs sporophytic capsule wall formation • Mp KNOX2 is involved in pectin biosynthesis during microsporogenesis • Secondary cell wall and pectin biosynthesis by KNOX2 genes is land plant universal The evolution of vasculature paved the way for land plants to colonize a vast array of terrestrial habitats. Dierschke et al. demonstrate that maternally expressed Marchantia polymorpha Class II KNOX controls sporophyte capsule secondary cell wall and pectin biosynthesis during sporogenesis, a function conserved throughout land plant evolution. [ABSTRACT FROM AUTHOR]

This study investigates the molecular mechanisms underlying fruit cracking in Akebia trifoliata, a phenomenon that significantly impacts fruit quality and marketability. Through comprehensive physiological, biochemical, and transcriptomic analyses, we identified key changes in cell wall components and enzymatic activities during fruit ripening. Our results revealed that ventral suture tissues exhibit significantly elevated activities of polygalacturonase (PG) and β-galactosidase compared to dorsoventral line tissues, indicating their crucial roles in cell wall degradation and structural weakening. The cellulose content in VS tissues peaked early and declined during ripening, while DL tissues maintained relatively stable cellulose levels, highlighting the importance of cellulose dynamics in fruit cracking susceptibility. Transcriptomic analysis revealed differentially expressed genes (DEGs) associated with pectin biosynthesis and catabolism, cell wall organization, and oxidoreductase activities, indicating significant transcriptional regulation. Key genes like AKT032945 (pectinesterase) and AKT045678 (polygalacturonase) were identified as crucial for cell wall loosening and pericarp dehiscence. Additionally, expansin-related genes AKT017642, AKT017643, and AKT021517 were expressed during critical stages, promoting cell wall loosening. Genes involved in auxin-activated signaling and oxidoreductase activities, such as AKT022903 (auxin response factor) and AKT054321 (peroxidase), were also differentially expressed, suggesting roles in regulating cell wall rigidity. Moreover, weighted gene co-expression network analysis (WGCNA) identified key gene modules correlated with traits like pectin lyase activity and soluble pectin content, pinpointing potential targets for genetic manipulation. Our findings offer valuable insights into the molecular basis of fruit cracking in A. trifoliata, laying a foundation for breeding programs aimed at developing crack-resistant varieties to enhance fruit quality and commercial viability. [ABSTRACT FROM AUTHOR]