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Pseudoalteromonas fuliginea sp. PS47 is a recently identified marine bacterium that has extensive enzymatic machinery to metabolize polysaccharides, including a locus that targets pectin‐like substrates. This locus contains a gene (locus tag EU509_03255) that encodes a pectin‐degrading lyase, called PfPL1, that belongs to polysaccharide lyase family 1 (PL1). The 2.2 Å resolution X‐ray crystal structure of PfPL1 reveals the compact parallel β‐helix fold of the PL1 family. The back side of the core parallel β‐helix opposite to the active site is a meandering set of five α‐helices joined by lengthy loops. A comparison of the active site with those of other PL1 enzymes suggests a catalytic mechanism that is independent of metal ions, such as Ca2+, but that substrate recognition may require metal ions. Overall, this work provides the first structural insight into a pectinase of marine origin and the first structure of a PL1 enzyme in subfamily 2. [ABSTRACT FROM AUTHOR]

The mixed enzymes-assisted mechanical bio-extraction method was first used to extract polysaccharides from Dendrobium officinale. Different parameters including the ratio of enzyme, the amount of enzyme, the grinding time, the extraction time and the solid/liquid ratio were investigated by single factor experiments and multifactorial experiments. Through the response surface methodology the optimal extraction conditions were obtained with the ratio of cellulase to pectinase was 2: 1 and total amount of enzyme was 0.23 mg, the grinding time of 11.48 min, the extraction time of 5.99 min. The obtained polysaccharide extracts were hydrolyzed and derivatized and then injected into high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF/MS) for monosaccharide composition analysis. After optimization of the chromatographic conditions (including mobile phase and column), twelve monosaccharides were successfully determined within 20 min. The proposed method provided satisfactory linearity with the correlation coefficients higher than 0.99, suitable recoveries (81.46–114.92 %), acceptable reproducibility ranging from 0.06 % to 4.77 %, low limits of detection (0.70–45.45 ng/mL). Compared with other methods, this method makes the extraction efficiency much higher and has the advantages of simple operation, environmental friendliness and mild extraction conditions. Therefore, this method can be used for the extraction of polysaccharides from plants and the determination of monosaccharides and has the potential to be used in more areas. [ABSTRACT FROM AUTHOR]

[Display omitted] • Extraction of polysaccharides from tobacco waste by EUAATPE was studied. • The yield and purity of polysaccharides from EUAATPE were highly improved. • PEUAATPE was compared and PHWE, PUAE, and PEAE. A powerful and innovative technique was developed to efficiently extract and refine polysaccharides from tobacco waste. This was achieved through a combination of enzyme and ultrasound-assisted extraction assisted aqueous two-phase extraction (EUAATPE). The formation of an aqueous two-phase system (ATPS) using various salts and ethanol was investigated. ATPS of 18.0 % (NH 4) 2 SO 4 (w/w) and 25.0 % ethanol (w/w) was chosen due to its favorable selection extraction ability and high recovery of 93.68 ± 0.40 %. By utilizing both single-factor experiments and response surface method (RSM), the key factors involved in the EUAATPE process were optimized. The optimal conditions were as follows: ultrasonic power 180 W, ultrasonic time 9 min, cellulase concentration 2.0 %, pectinase concentration 1.0 %, extraction temperature 50 °C, extraction time 1.5 h, and liquid-to-solid ratio 30:1 (g/g). Under the optimal conditions, the extraction yield of polysaccharides was 6.72 ± 0.11 (mg/g), and the purity of the polysaccharides from the bottom phase was 78.73 ± 3.17 %. EUAATPE resulted in a significant enhancement in the extraction yield and purity of polysaccharides from tobacco waste compared to traditional methods such as hot water extraction (HWE), ultrasound-assisted extraction (UAE) and enzyme-assisted extraction (EAE). Polysaccharides of tobacco waste obtained from various methods had analogous monosaccharide compositions, different molar ratio compositions and surface structure characteristics. Moreover, all polysaccharides exhibited a certain extent antioxidant activities and polysaccharides from the bottom phase (PBP) extracted by EUAATPE showed superior antioxidant activity. Hence, EUAATPE, being an innovative and eco-friendly extraction technique, presents a productive substitute for extracting and refining polysaccharides from discarded tobacco resources. [ABSTRACT FROM AUTHOR]

In the experiment, the self-selected Chinese medicine feed additive was fermented by co-fermentation of bacteria and enzymes. The content of crude polysaccharide in the supernatant of Chinese medicine before and after fermentation was used as the index to determine the fermentation quality. The fermentation parameters such as strain, enzyme preparation and fermentation conditions were optimized by single factor test and orthogonal test. The fermentation strains were screened by single fermentation and double fermentation. The results showed that the two-bacteria fermentation effect was better, and the optimal ratio of Bacillus subtilis∶Lactobacillus plantarum was 1∶9. Cellulase and pectinase were added on the basis of microbial fermentation of traditional Chinese medicine, and single enzyme fermentation and double enzyme fermentation were adopted to ferment traditional Chinese medicine. The results showed that the double enzyme fermentation effect was better, the optimal ratio of cellulase∶pectinase was 3∶7, and the optimal enzyme addition level was 150 U/g. Four kinds of fermentation conditions were optimized by orthogonal experiment, including solid-liquid ratio, fermentation temperature, fermentation time and inoculation amount. The experiment indicates that the optimal fermentation conditions are solid-liquid ratio 1∶ 1.2 g/mL, fermentation temperature 35 ℃, fermentation time 60 h, inoculation amount 12%. Under the fermentation process, the crude polysaccharide content is 280.46 mg/g. [ABSTRACT FROM AUTHOR]

In this work, the effects of four different extraction methods, acid (HCl), alkali (NaOH), enzymes (cellulase/pectinase), and buffer (pH 7.0) on the physicochemical properties and functionalities of burdock pectin were systematically investigated and compared. Buffer extraction gave a low yield (2.8 %) and is therefore limited in its application. The acid treatment hydrolyzed the neutral sidechains and gave a homogalacturonan content of 72.6 %. By contrast, alkali and enzymes preserved the sidechains while degrading the polygalacturonan backbone, creating a rhamnogalacturonan-I dominant structure. The branched structure, low molecular weight, and high degree of methylation (42.3 %) contributed to the interfacial adsorption, emulsifying capacity, and cellular antioxidant activity of the enzyme-extracted product. For the acid-extracted product, the strong intramolecular electrostatic repulsion restricted the formation of a contact interface to prevent coalescence of the emulsion. In addition, they did not have sufficient reducing ends to scavenge free radicals. Although a high branching size (5.0) was adopted, the low degree of methylation (19.5 %) affected the emulsifying capacity of the alkali-extracted products. These results provide useful information for pectic polysaccharides production with tailored properties. [Display omitted] • Acid, alkali, enzymes and buffer were used to extract pectic polysaccharides from burdock. • Acid treatment yielded homogalacturonan-rich pectic polysaccharides • Alkaline or enzyme extraction provided the rhamnogalacturonan-I dominant structure. • The emulsifying and antioxidant capacity of acid-extracted samples were constrained. • The small molecular size and branched structure favored the enzyme-extracted samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • Acidic pH caused enhanced protein-pectin interactions. • Oleosome separation is more efficient at acidic pH. • Alkaline extraction improves purity of oleosomes fraction. • Polysaccharides play a key role for the physical stability of oleosome at acidic pH. • Hydrolysis of pectins improves oleosome stability towards coalescence at alkaline pH. Oleosomes are lipid composites providing energy storage in oilseeds. They possess a unique structure, comprised of a triglyceride core stabilized by a phospholipid-protein membrane, and they have shown potential to be used as ingredients in several food applications. Intact oleosomes are extracted by an aqueous process which includes soaking, milling, and gravitational separation. However, the details of the complexes formed between oleosomes, proteins and pectin polysaccharides during this extraction are not known. It was hypothesized that pectins play an important role during the oleosome separation, and different proteins will be complexed on the surface of the oleosomes, depending on the pH of extraction. Rapeseed extracts were treated with and without pectinase (Pectinex Ultra SP-L) and extracted at pH 5.7 or 8.5, as this will affect electrostatic complexation. Acidic conditions led to co-extraction of storage proteins, structured as dense oleosome emulsions, stabilized by a network of proteins and polysaccharides. Pectinase intensified this effect, highlighting pectic polysaccharides' role in bridging interactions among proteins and oleosomes under acidic conditions. The presence of this dense interstitial layer around the oleosomes protected them from coalescence during extraction. Conversely, under alkaline conditions, the extraction process yielded more purified oleosomes characterized by a larger particle size, most likely due to coalescence. Nevertheless, pectinase addition at pH 8.5 mitigated coalescence tendencies. These results contribute to a better understanding of the details of the colloidal complexes formed during extraction and can be used to modulate the composition of the extracted fractions, with significant consequences not only for yields and purity but also for the functional properties of the ingredients produced. [ABSTRACT FROM AUTHOR]

Objectives: In this study, we aimed to establish an efficient method for the extraction of radix Morindae officinalispolysaccharide (MOP) by applying ultrasonic technology and by optimizing the parameters through response surface methodology (RSM) based on the central composite design. Materials and Methods: Ultrasound-assisted enzymatic extraction (UAEE) was performed to extract the MOP. We applied an orthogonal array design to optimize the concentration of enzymes (cellulose, pectinase, and papain). The extraction parameters were optimized based on the RSM technique. Furthermore, the effects of ultrasound-assisted enzymatic treatment on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity by the MOP was optimized using the RSM technique. Results: According to our results, 1.0% cellulase, 1.5% pectinase, and 1.0% papain were the optimum concentrations of the enzyme (calculated based on the percentage dry weight of radix Morindae officinalis powder). The optimum conditions of extraction were as follows: 21 mL/g solvent–solid ratio, 280 W, pH of 5.3, and temperature of 50°C. Under these conditions, the yield of MOPs and DPPH-scavenging activity of MOP were 23.68% ± 0.52% (n = 3) and 117.26 ± 2.73 mg Vitamin C/100 g dry weight (n = 3), respectively. The overall desirability was 1.03 ± 0.01 (n = 3). Conclusion: UAEE was effective in the extraction of MOP, and RSM technique was adequate to design and optimize the extraction parameters. [ABSTRACT FROM AUTHOR]

The lotus (Nelumbo nucifera Gaertn.) is the largest aquatic vegetable in Asia. The lotus seedpod (LS) is an inedible part of the mature flower receptacle of the lotus plant. However, the polysaccharide isolated from the receptacle has been less studied. The purification of LS resulted in two polysaccharides (LSP-1 and LSP-2). Both polysaccharides were found to be medium-sized HG pectin, with a Mw of 74 kDa. Their structures were elucidated via GC–MS and NMR spectrum and proposed as the repeating sugar units of GalA connected via α-1,4-glycosidic linkage, with LSP-1 having a higher degree of esterification. They have certain content of antioxidant and immunomodulatory activities. The esterification of HG pectin would have an adverse effect on these activities. Furthermore, the degradation pattern and kinetics of LSPs by pectinase conformed to the Michaelis-Menten model. There is a large amount of LS, resulting from the by-product of locus seed production, and thus a promising source for the isolation of the polysaccharide. The findings of the structure, bioactivities, and degradation property provide the chemical basis for their applications in the food and pharmaceutical industries. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract The fruit of hawthorn (Crataegus pinnatifida Bge. var. major) is rich in pectic polysaccharides and has been used for centuries in China as food and herb. Hawthorn pectin (HP) recently has attracted rising attention due to the reported functional properties (e.g. gelling, emulsification) and health benefits towards the cardiovascular system. In this study, using hawthorn wine residue as raw material, a high methoxylated pectic polysaccharide HSP (degree of esterification up to 70%) was obtained by mild acid extraction (yield up to 20 wt%). Results from HPSEC coupled with triple detector revealed a widely dispersed (polydispersity index = 2) pectic polysaccharide with weight average molecular weight (Mw) of 111.7 kDa. Compared to pectin extracted from the hawthorn fruit, HSP showed a relatively lower molecular weight and higher polydispersity index (PDI), which suggested that the degradation of HP molecular chain during the wine-making processing (fermentation). Functionally, HSP demonstrated relatively high apparent viscosity but did not form gel in aqueous solution at concentrations up to 8 wt%. Structurally, HSP molecule was composed of over 70 mol% of 4-Gal p A, with a small amount of glucose, galactose, xylose and arabinose. Under pectinase hydrolysis, over 95 wt% of the HSP was degraded into small fragments and monosaccharides; a small portion of relatively higher molecular weight rhamnose rich fragments were obtained from the hydrolytes. Combining both methylation analysis and 1D NMR spectroscopy, structural features of HSP were partially elucidated. Graphical abstract Image 1 Highlights • A high methoxylated pectic polysaccharide was extracted from hawthorn wine residue. • Physicochemical, functional and partial structural features were investigated. • Molecular degradation of pectin took place during wine-making process. • Pectin showed relatively high apparent viscosity but did not form gel. • Pectin contained mainly HG, but small portion of RG-I and RG-II were also detected. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The polysaccharides from green sweet pepper (CAP) presented antineoplastic effects against mammary tumor lineages. • CAP treatment reduced the gene expression of VEGF in tumor cells in vivo and in vitro. • CAP treatment reduced the area of vessels in Ehrlich tumor. • CAP treatment induced necrosis in Ehrlich solid tumors. • CAP treatment increased the levels of IL-6 in Ehrlich tumors in mice. Abstract The present study investigated the antineoplastic effects of pectic polysaccharides that were extracted from green sweet pepper (Capsicum annuum [CAP]) in the Ehrlich carcinoma in mice and in human mammary tumor lineages. After the subcutaneous inoculation of 2 × 106 Ehrlich tumor cells, Female Swiss mice received 50, 100, or 150 mg/kg CAP or vehicle orally once daily or methotrexate (2.5 mg/kg, i.p., every 5 days) for 21 days. CAP dose-dependently reduced Ehrlich tumor growth. It also reduced the viability of MCF-7, MDA-MB-231, and MDA-MB-436 human mammary cell lineages. Treatment with CAP reduced the gene expression of vascular endothelial growth factor in vivo and in vitro , reduced vessel areas of the tumors, and induced necrosis in Ehrlich solid tumors. CAP treatment significantly increased Interleukin-6 in tumors. The antineoplastic effect of CAP appears to depend on the regulation of inflammation and angiogenesis. Further studies are encouraged to better understand the CAP potential for the treatment of breast tumors. [ABSTRACT FROM AUTHOR]

To develop new immunostimulatory ingredients, green tea polysaccharides were obtained by pectinase-assisted extraction. The present study investigated the immune stimulating and protective ability of polysaccharides from pectinase digests of green tea (PPGT) against infectious disease and the mechanisms involved. Macrophages stimulated with PPGT exhibited dose-dependent increases in nitric oxide, tumour necrosis factor-α (TNF-α) production and phagocytosis. PPGT increased phosphorylation of mitogen-activated protein (MAP) kinase, nuclear factor-kappaB (NFκB) and signal transducers and activators of transcription (STATs) through toll-like receptor 4 (TLR4) activation. The survival of mice infected with a lethal dose (1 × 107 CFU) of S. typhimurium was significantly extended by PPGT administration. Furthermore, PPGT induced production of cytokines (interleukin-12, interferon-γ, and TNF-α) in mice infected with a sub-lethal dose (1 × 105 CFU) of S. typhimurium. Furthermore, PPGT was significantly promoted natural killer cell and cytotoxic T lymphocyte activity. The above results lead to conclude that PPGT have a potent immune stimulating effect on immune cells via TLR4 pathway. [ABSTRACT FROM AUTHOR]

The complex coacervation of pea protein isolate (PPI) with commercial pectic polysaccharides [high methoxy citrus pectin (P90, 90 representing DE), apple pectin (P78) sugar beet pectin (P62), low methoxy citrus pectin (P29)] of different degrees of esterification (DE) [and galacturonic acid content (GalA)] and blockiness (DB), was investigated. The maximum amount of coacervates formed at a biopolymer weight mixing ratio of 4:1 for all PPI-pectin mixtures, with the exception of PPI-P29 where maximum coacervation occurred at the 10:1 mixing ratio. The pH at which maximum interactions occurred was pH 3.4–3.5 (PPI: P90/P78) and 3.7–3.8 (PPI: P62/P29). PPI complexed with pectins with high levels of DE (low levels of GalA) and DB displayed greater interactions at optimal mixing conditions compared to pectin having lower levels of esterification and blockiness. The addition of P78 to PPI greatly increased protein solubility at pH 4.5. [ABSTRACT FROM AUTHOR]

Antiulcer potency and inhibitory effects on Helicobacter pylori of structurally defined low molecular weight modified pectin from turmeric (MTrPP) has been previously demonstrated by us. Given that ulcer is a disorder characterized by inflammatory responses leading to initiation, aggravation and perpetuation of disease conditions, the present study aims to understand the possible anti–inflammatory mechanisms through which MTrPP delivered antiulcer effects. Rats triggered with early phase gastric inflammation (LPS) followed by ulcer induction (swim–stress) were pretreated with MTrPP (150 mg/kg b.w.) for 14 days. Inflammation and ulcer–specific markers were screened to assess the protective effects. MTrPP offered up to 91% protection by limiting the production of pro–inflammatory factors (TNF–α, IL–8, NF–κB) and by the tight differential regulation of cyclooxygenase (COX–1, 2), mitogen–activated–protein–kinase ( p –p38, p –ERK–1/2) and matrix metalloproteinase (pro–MMP–9). MTrPP showed modulatory effects through inhibition of galectin–3, oxidative stress, H + ,K + –ATPase and elicitation of gastro–protective mediators such as, mucin, prostaglandin E 2 , NO x , zinc, IgA etc. Results revealed that MTrPP mediated the overall protection by creating an environment conducive to protection by switching from the inflammatory to anti–inflammatory phase via IL–10 over expression. [ABSTRACT FROM AUTHOR]

Water-extractable arabinogalactan proteins (AGP) (the main constituent) and pectic polysaccharides were isolated from tree greenery of Picea abies . The carbohydrate part of AGP macromolecules consisted of AG-II, the side chains of which were represented by 1,6- and 1,3,6-β- d -Gal p , T-α- l -Ara f , 1,3- and 1,5-α- l -Ara f , T-β-D - Glc p A and 1,4-β-D - Glc p A, T-α- l - R ha p , T-α- l -Fuc p and 4- O -Me-α- l -Fuc p residues. It was established that the unusual 4- O -Me-α- l -Fuc p monosaccharide are located on the non-reducing ends of the side chains of carbohydrate part of AGP macromolecules, and are bound to 1,4-β- d -Glc p A residues by 1,4-bonds. The backbone of pectin macromolecules consisted mostly of 1,4-α- d -galactopyranosyluronan and RG-I, which side chains were represented by highly branched 1,5-α- l -arabinan. It was shown that RG-I is characterized mainly by short segments, which are alternated with the regions of the non-acetylated and non-methyl-esterified galacturonan. The study revealed that at least a part of the pectin is strongly associated with AGP. It was indicated that the RG-I segments are separated from the AGP-bound pectin by regions of 1,4-α- d -galactopyranosyluronane. [ABSTRACT FROM AUTHOR]

The main route for acrylamide formation is the reaction between reducing sugars and asparagine. As foods pH modulates acrylamide formation, cooking under the lowest pH is a possible mitigation strategy, as long as it does not compromise the expected foods sensorial characteristics. Polymeric acid compounds, such as pectin or pectate, which are acidic polysaccharides, can provide acidity without significant interference in taste or colour. To prove this hypothesis, biscuits were prepared with tartaric acid (control to acidic effect), and galacturonic acid in monomeric (GalA), oligomeric, and polymeric forms (pectin or pectate). While 1% GalA leads to 95% increase in acrylamide, biscuits prepared with 5% pectin had a 67% decrease. Replacing sucrose with fructose increased the acrylamide levels in control biscuits above the benchmark level of 150 μg/kg recommended by EFSA for children. However, addition of pectin/pectate had an effective acrylamide mitigation by lowering its content below these indicative values. [ABSTRACT FROM AUTHOR]

In this work, based on response surface methodology (RSM), an optimized method of extracting water-soluble polysaccharide from pomegranate peel (PPP) with pectinase was proposed. Additionally, the chemical composition and the antioxidant activities of the extracted PPP were studied. The effects of three factors of enzymolysis time, ratio of liquid to solid and dosage of enzyme on the PPP yield were investigated. The experimental results showed that the optimal conditions were as following: enzymolysis time 19.70 min, ratio of liquid to solid 20.5:1(mL/g), dosage of enzyme 0.68%. Under the best conditions, the maximum PPP yield was 27.3 ± 0.08%. FT-IR and GC–MS revealed that PPP was the typical acidic heteropolysaccharides and mainly consisted of d -mannose (19.30%), d -galactose (47.93%) and l -arabinose (23.08%). Moreover, the antioxidant activity assay in vitro showed that PPP exhibited strong reducing power and good scavenging activities on superoxide anion, hydroxyl, and DPPH radicals. The PPP extracted with pectinase had excellent antioxidant properties and could be developed into a new type of dietary supplement or functional food. [ABSTRACT FROM AUTHOR]

Malpighia emarginata is a tropical fruit plant, found naturally in the Caribbean islands and South America that produces an edible fruit known as acerola or Barbados Cherry. Its polysaccharides were obtained by aqueous extraction, subjected to a freezing and thawing process and ultrafiltration. A homogeneous fraction (ACWS-01E) was analyzed by sugar composition, HPSEC, methylation and NMR spectroscopy analyses. The results showed an arabinan-rich pectic polysaccharide, with 6.1 × 10 4 g/mol and formed mainly by a high methyl esterified (DM = 86%) homogalacturonan and branched arabinan. This latter is anchored in type I rhamnogalacturonan regions. The main chain of arabinan consisted of (1 → 5)-linked α-Ara f , branched only at O -3. The potential ACWS-01E intracellular antioxidant activity against H 2 O 2 -induced oxidative stress in murine fibroblast cell line (3T3) was determined by DCFH-DA assay. The treatment with ACWS-01E significantly reduced H 2 O 2 -induced cytotoxic effect and the levels of reactive oxygen species (ROS). These findings suggested that ACWS-01E protected and improved NIH 3T3 cell viability from H 2 O 2 -induced toxicity by decreasing intracellular levels of ROS. [ABSTRACT FROM AUTHOR]

The effect of ethanol addition (0 − 30% v/v) on subcritical water extraction (SCWE) of pectic polysaccharides from passion fruit peel was investigated. The peel was extracted in a batch-type reactor at the treatment temperatures range of 100 − 160C. As a result, low molecular weight pectic polysaccharides in a range of 15.4 − 38.5 kDa were obtained. Higher treatment temperatures tended to give higher yields while the addition of ethanol gave adverse effect, except for adding small amount at high temperatures. The maximum yield (12.28% dry matter basis) was obtained from the treatment at 140C using 10% ethanol. The major composition of extracted pectic polysaccharides was galacturonic acid (72.11 − 94.76%). Additionally, this study demonstrated that the addition of ethanol resulted in pectic polysaccharides that possessed higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and total phenolic content (TPC). Practical Applications Subcritical water extraction (SCWE) is an environmentally friendly method that can be used for extraction of pectic polysaccharides from passion fruit peel, which is a major waste from juice production. Addition of ethanol was successful to enhance the extractability of some bioactive compounds in the peel and resulted in pectic polysaccharides with higher total phenolic content (TPC) and free radical scavenging activity, which might be useful as functional food ingredients. [ABSTRACT FROM AUTHOR]

BACKGROUND Genes encoding pectic enzymes were introduced into wild-type potato Karnico. Cell wall materials were extracted from Karnico and transgenic lines expressing β-galactosidase ( β-Gal-14) or rhamnogalacturonan lyase ( RGL-18). Pectic polysaccharides from the β-Gal-14 transgenic line exhibited rhamnogalacturonan-I structural elements with shorter galactan side chains, whereas the RGL-18 transgenic line had less rhamnogalacturonan-I structures than Karnico. Xyloglucan in primary cell walls interacts with pectin and other cell wall polysaccharides and controls cell growth. RESULTS Xyloglucan extracts from transgenic lines had different levels of monosaccharides compared to wild-type. Most XXGG-type xyloglucans from Karnico and RGL-18 alkali-extractable extracts predominantly consisted of XXGG and XSGG building blocks. Karnico and RGL-18 4 mol L−1 extracts had small proportions of the XXXG-type xyloglucan, whereas β-Gal-14 extracts also contained the XXXG-type xyloglucan. The peak ratios of XSGG/ XXGG were 1.9, 2.4 and 1.1 for 4 mol L−1 extracts of Karnico, RGL-18 and β-Gal-14 lines, respectively. CONCLUSION After transgenic modification on pectin, the xyloglucan building blocks may have been changed. The β-Gal-14 lines mostly present XXXG-type repeating units instead of the XXGG-type in 4 mol L−1 extracts. The ratio of XSGG/ XXGG repeating units also changed, indicating that the transgenic modification of pectin altered xyloglucan structure during plant development. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Sijunzi Decoction (SJZD) is a formula used for the treatment of spleen deficiency and gastrointestinal diseases in Traditional Chinese Medicine. Polysaccharides are reported to be the main components of SJZD responsible for its bio-functions. However, highly purified and clearly characterized polysaccharides from SJZD are not well described. Here we obtained a purified polysaccharide (SJZDP-II-I) from SJZD using ion exchange chromatography and gel filtration. Structure analysis by FT-IR and NMR identified SJZDP-II-I as a typical pectic polysaccharide with homogalacturonan and rhamnogalacturonan type I regions and arabinogalactan type I and II as side chains. In vitro studies indicated that SJZDP-II-I treatment could significantly enhance the total antioxidant capacity of SW480 cells, resulting from the promoted expressions of antioxidant enzymes and their master regulator PGC-1α, which would be valuable for further research and applications. [ABSTRACT FROM AUTHOR]

Despite it is used as a nutraceutical against diabetes and obesity, the mechanism of action of bee pollen is still unclear. Pectic bee pollen polysaccharide (RBPP-P) was isolated from Rosa rugosa, and its structure was characterized by 13C-NMR and Fourier transform-infrared spectroscopy (FT-IR). Using high glucose and fatty acids-treated HepG2 cells and high fat diet (HFD)-induced obesity mice, we detected its effect on insulin function and lipid metabolism based on autophagy. RBPP-P contained arabinogalactan, rhamnogalacturonan I, and homogalacturonan domains. In vivo studies demonstrated that RBPP-P markedly ameliorated insulin resistance, glucose intolerance, and liver steatosis in obese mice. The suppressive effects of RBPP-P on liver steatosis and triglyceride content were mediated by increased autophagy and lipase expression in liver. In AMPK knockdown cells (prkaa 1/2-/- MEF) and HFD-fed mice tissues (liver, gonadal white adipose, and inguinal white adipose), RBPP-P enhanced autophagy in AMPK/mTOR-dependent way in liver, but not in adipose tissue. These findings demonstrated that bee pollen polysaccharide alleviated liver steatosis and insulin resistance by promoting autophagy via an AMPK/mTOR-mediated signaling pathway, suggesting that RBPP-P could be a novel therapeutic agent used for the treatment of obesity and diabetes. [ABSTRACT FROM AUTHOR]

The aim of this work was to investigate the core structure of a Dendrobium huoshanense polysaccharide DHPD1 required for the inhibition of lens epithelial cell apoptosis. In order to obtain the fragments containing the core domain, pectinase was employed to hydrolyze DHPD1. After 24 h reaction, it is interesting that the hydrolyzation seemed to be stopped, leading to a final enzymatic fragment DHPD1-24 with molecular weight about 1552 Da. Compared to DHPD1, although the bioactivity is decreased, DHPD1-24 remained the ability to inhibit the H 2 O 2 -induced apoptosis of human lens epithelial (HLE) cells via suppressing the MAPK signaling pathways. These results suggested that DHPD1-24 might be the core domain required for DHPD1 to inhibit HLE cell apoptosis. Methylation analysis showed DHPD1-24 was composed of (1 → 5)-linked-Ara f , (1 → 3,6)-linked-Man p , 1-linked-Glc p , (1 → 4)-linked-Glc p , (1 → 6)-linked-Glc p , (1 → 4,6)-linked-Glc p , (1 → 6)-linked-Gal p and 1-linked-Xyl p in a molar ratio of 1.06:1.53:2.11:2.04:0.93:0.91:0.36:1.01. Moreover, the primary structural features of DHPD1-24 were characterized by NMR spectrum. [ABSTRACT FROM AUTHOR]

The effectiveness of enzyme-mediated-maceration in red winemaking relies on the use of an optimum combination of specific enzymes. A lack of information on the relevant enzyme activities and the corresponding polysaccharide-rich berry cell wall structure is a major limitation. This study used different combinations of purified recombinant pectinases with cell wall profiling tools to follow the deconstruction process during winemaking. Multivariate data analysis of the glycan microarray (CoMPP) and gas chromatography (GC) results revealed that pectin lyase performed almost as effectively in de-pectination as certain commercial enzyme mixtures. Surprisingly the combination of endo -polygalacturonase and pectin-methyl-esterase only unraveled the cell walls without de-pectination. Datasets from the various combinations used confirmed pectin-rich and xyloglucan-rich layers within the grape pomace. These data support a proposed grape cell wall model which can serve as a foundation to evaluate testable hypotheses in future studies aimed at developing tailor-made enzymes for winemaking scenarios. [ABSTRACT FROM AUTHOR]

Copigmentation plays an important role in the colors provided by anthocyanins. However, little attention has been paid to the interaction between anthocyanins and cell wall compounds (e.g. polysaccharides) and the impact of this interaction on anthocyanins color, a fundamental issue to be considered in industrial applications of these pigments as food colorants. The copigmentation binding constants ( K CP ) for the interaction between malvidin-3- O -glucoside and (+)-catechin in the presence of low methoxylated pectic polysaccharide were determined. The values obtained showed that in the presence of pectic polysaccharide the copigmentation binding constants decreased. These results probably suggest the occurrence of competition equilibrium in which the presence of pectin limited the association between catechin and oenin. 1 H NMR studies revealed that the dissociation constant determined for these complexes was very similar in absence and presence of 1.5 g/L pectin with this polysaccharide apparently not affecting the strength of anthocyanin-catechin binding. [ABSTRACT FROM AUTHOR]

The effects of cellulase, pectinase and xylanase on the polysaccharide yield were studied by single-factor tests. Then the Plackett-Burman and steepest ascent experiment were conducted according to the results of single-factor tests. Finally, the optimum conditions of extracting polysaccharide from white hyacinth bean were obtained so as to conduct the further experiment. The results showed that pH (p=0.0599), cellulose (p=0.0756) and ratio of water to material (p=0.0951) are important factors of extracting polysaccharides. And the factors that has positive effect on the polysaccharides yield are: cellulose, pectinase, xylanase, ratio of water to material, extraction time and pH. While the extraction temperature has negative influence to polysaccharides yield. The optimum conditions of polysaccharides extraction were: pH was 7.8, the addition amount of cellulose was 2.7% and the ratio of water to material was 62. The polysaccharides yield was the 3.23% under these conditions. [ABSTRACT FROM AUTHOR]

Background: In pea seeds (Pisum sativum L.), the presence of the Def locus determines abscission event between its funicle and the seed coat. Cell wall remodeling is a necessary condition for abscission of pea seed. The changes in cell wall components in wild type (WT) pea seed with Def loci showing seed abscission and in abscission less def mutant peas were studied to identify the factors determining abscission and non-abscission event. Methods: Changes in pectic polysaccharides components were investigated in WT and def mutant pea seeds using immunolabeling techniques. Pectic monoclonal antibodies (1 → 4)-β-d-galactan (LM5), (1 → 5)-α-l-arabinan(LM6), partially de-methyl esterified homogalacturonan (HG) (JIM5) and methyl esterified HG (JIM7) were used for this study. Results: Prior to abscission zone (AZ) development, galactan and arabinan reduced in the predestined AZ of the pea seed and disappeared during the abscission process. The AZ cells had partially de-methyl esterified HG while other areas had highly methyl esterified HG. A strong JIM5 labeling in the def mutant may be related to cell wall rigidity in the mature def mutants. In addition, the appearance of pectic epitopes in two F3 populations resulting from cross between WT and def mutant parents was studied. As a result, we identified that homozygous dominant lines (Def/Def) showing abscission and homozygous recessive lines (def/def) showing non-abscission had similar immunolabeling pattern to their parents. However, the heterogeneous lines (Def/def) showed various immunolabeling pattern and the segregation pattern of the Def locus. Conclusions: Through the study of the complexity and variability of pectins in plant cell walls as well as understanding the segregation patterns of the Def locus using immunolabeling techniques, we conclude that cell wall remodeling occurs in the abscission process and de-methyl esterification may play a role in the non-abscission event in def mutant. Overall, this study contributes new insights into understanding the structural and architectural organization of the cell walls during abscission. [ABSTRACT FROM AUTHOR]

Four polysaccharide fractions were isolated from young barley leaves treated with or without pectinase followed by ethanol fractionation. Among the polysaccharide fractions, BLE-P isolated from pectinase digested with a high molecular weight had the most enhanced macrophage stimulatory activity, indicating that pectinase digestion of barley leaf is a useful method for enhancement of its activity. BLE-P was further purified by column chromatography to identify the chemical and structural properties. BLE-P-I eluted in void volume fraction showed potent macrophage stimulatory activity. Monosaccharide composition and linkage analysis indicated that at least three kinds of polysaccharide, that is, glucuronoarabinoxylan (GAX; 40–45%), rhamnogalacturonan-I (RG-I) with branching mainly involving a type II arabinogalactan (AG-II) side chain (30–35%), and linear glucan such as starch and cellulose (less than 10%) coexisted in BLE-P-I. Given the association with macrophage stimulatory activity, it is likely that the GAX and to the RG-I polysaccharide branched with an AG-II side chain may be important for expression of the activity in barley leaf. [ABSTRACT FROM AUTHOR]

This research sheds a new light on the potency of non-starch polysaccharide (NSP) enzymes xylanase, glucanase, and pectinase to save on total protein and digestible amino acids in broiler feed. It was demonstrated previously that advised dosages of further described NSP enzyme concepts can decrease FCR1500 by ≥3% in broilers on various non-reformulated diets, allowing for energy reformulation. Hence the hypothesis that higher dosages are needed to release sufficient NSP encapsulated protein for protein and digestible amino acid reformulation. Two NSP enzyme concepts at double the advised dosage were compared with protease at advised dosage (positive control, confirmed in former trial) in an experimental broiler performance essay. A standard (S) and negative control (NC) diet with relatively 3% less total protein and digestible amino acids, were formulated. The NC diet was supplemented with 1 of 3 commercial enzymes: 1) 40,000 endo-1,4-β-xylanase XU/g (EC 3.2.1.8) and 9,000 endo- 1,3(4)-β-glucanase BGU/g (EC 3.2.1.6) (XG) (double the advised dosage, 200 ppm), 2) 10,700 endo-1,4-β-xylanase XU/g (EC 3.2.1.8), 6,150 endo-1,3(4)-β-glucanase BGU/g (EC 3.2.1.6) and 230 pectinase PGLU/g (EC 3.2.1.15) (XGP) (double the advised dosage, 400 ppm) or 3) concentrated protease (PRO) at advised dosage (300 ppm). Performance (feed intake, body weight gain and feed to gain) were similar in broilers fed XG, XGP and PRO supplemented NC diets and equaled the S diet. The present study demonstrates that 200 and 400ppm of mentioned XG and XGP concepts respectively, enable a 3% reformulation on total protein and digestible amino acids. This allows for considerable cost saving of common broiler formula, in present case 3.97 to 4.67€/ton less in starter and 2.37 to 3.07€/ton less in grower feed (calculation of raw materials based on Belgian ingredient prices July 2015). This is mediated by 1) a total protein and digestible amino acid reduction, using 2) mentioned NSP enzyme concepts that are about 43 to 20% cheaper (at double the advised dosage) than protease in current European settings. [ABSTRACT FROM AUTHOR]

A structural characterization of polysaccharides from edible tropical fruit named starfruit ( Averrhoa carambola L.) was carried out. After the purification steps, two homogeneous fractions were obtained. Fraction 50R was composed of rhamnose, arabinose, galactose and uronic acid in 4.3:56.2:37.4:2 M ratio, respectively and fraction 10R was composed of rhamnose, arabinose, galactose and uronic acid in 2.8:65.8:28.5:3 M ratio, respectively. Methylation and NMR spectroscopy analyses showed that these fractions are formed by pectic arabinogalactans, which contain (1 → 3), (1 → 6) and (1 → 3,6)-linked Gal p units. The side chains have 3- O -, 5- O - and 3,5-di- O -linked α-Ara f and nonreducing end-units of α-Ara f , Ara p , β-Gal p and α-Glc p A. These arabinogalactans were linked to type I rhamnogalacturonans. [ABSTRACT FROM AUTHOR]

Different mechanisms responsible for the development of the hard-to-cook defect in common beans during storage, their soaking behavior and softening during thermal treatment have been previously suggested. However, these mechanisms have not been sufficiently confirmed by direct molecular evidence. This research aimed at gaining a detailed mechanistic insight into changes occurring in Canadian wonder bean pectic polysaccharides during storage, soaking and/or thermal treatment in different brine solutions in relation to the development and manifestation of the hard-to-cook (HTC) defect. Both fresh or easy-to-cook (ETC) and stored (HTC) bean samples were either soaked or soaked and thermally treated in demineralized water, solutions of Na 2 CO 3 and CaCl 2 salts followed by extraction of cell wall materials. Pectic polysaccharide properties examined included sugar composition, degree of methylesterification (DM), extractability and molar mass (MM). The DM of pectin from ETC and HTC beans was similar but low (< 50%). Upon (pre)treatment in a Na 2 CO 3 solution, solubilization of pectic polysaccharides, especially the strongly bound chelator- (CEP) and Na 2 CO 3 - (NEP) extractable pectins was enhanced leading to increased amounts of water extractable pectin (WEP). Also, there was a decrease in high MM polymers paralleled by an increase in β-elimination degradation products. These observations are in line with the fast cooking behavior of beans (pre)treated in a Na 2 CO 3 solution. In contrast, (pre)treatment in a CaCl 2 solution hindered softening leading to the failure of the beans to cook. The beans (pre)treated in a CaCl 2 solution showed increased high MM polymers and lack of cell wall separation. Therefore, it can be inferred that development of the hard-to-cook defect in Canadian wonder beans during storage and its manifestation during soaking and subsequent thermal treatment is largely reflected by the pectic polysaccharide properties in line with the pectin hypothesis. Our data suggest the release of Ca ++ leading to pectin cross-linking and the increase or decrease of β-elimination depolymerization. However, the relatively high amounts of neutral sugars and strongly bound NEP in HTC seeds do not allow to rule out the possible existence of non-Ca ++ based pectin cross-linking. [ABSTRACT FROM AUTHOR]

Background and aims Many fruits soften during ripening, which is important commercially and in rendering the fruit attractive to seed-dispersing animals. Cell-wall polysaccharide hydrolases may contribute to softening, but sometimes appear to be absent. An alternative hypothesis is that hydroxyl radicals (*OH) non-enzymically cleave wall polysaccharides. We evaluated this hypothesis by using a new fluorescent labelling procedure to 'fingerprint' *OH-attacked polysaccharides. Methods We tagged fruit polysaccharides with 2-(isopropylamino)-acridone (pAMAC) groups to detect (a) any mid-chain glycosulose residues formed in vivo during *OH action and (b) the conventional reducing termini. The pAMAC-labelled pectins were digested with Driselase, and the products resolved by high-voltage electrophoresis and high-pressure liquid chromatography. Key Results Strawberry, pear, mango, banana, apple, avocado, Arbutus unedo, plum and nectarine pectins all yielded several pAMAC-labelled products. GalA-pAMAC (monomeric galacturonate, labelled with pAMAC at carbon-1) was produced in all species, usually increasing during fruit softening. The six true fruits also gave pAMACUA-GalA disaccharides (where pAMACUA is an unspecified uronate, labelled at a position other than carbon-1), with yields increasing during softening. Among false fruits, apple and strawberry gave little pAMACUA-GalA; pear produced it transiently. Conclusions GalA-pAMAC arises from pectic reducing termini, formed by any of three proposed chain-cleaving agents (*OH, endopolygalacturonase and pectate lyase), any of which could cause its ripening-related increase. In contrast, pAMACUA-GalA conjugates are diagnostic of mid-chain oxidation of pectins by *OH. The evidence shows that *OH radicals do indeed attack fruit cell wall polysaccharides non-enzymically during softening in vivo. This applies much more prominently to drupes and berries (true fruits) than to false fruits (swollen receptacles). *OH radical attack on polysaccharides is thus predominantly a feature of ovary-wall tissue. [ABSTRACT FROM AUTHOR]

Response surface methodology (RSM) was employed to optimize the microwave-assisted extraction (MAE) process of pectic polysaccharide (TPPs) from tangerines peel. The optimal extraction conditions were as follows: microwave power 704 W, extraction temperature 52.2 °C, and extraction time 41.8 min Under these conditions, the experimental yield was 19.9 ± 0.2%. The purified pectic polysaccharide TPPs-2-1 was successfully obtained by anion-exchange and gel filtration chromatography. TPPs-2-1, linked mainly by α-glycosidic bonds, consisted of galacturonic acid (GalA), arabinose (Ara), galactose (Gal), rhamnose (Rha), glucose (Glc) and mannose (Man) with the average molecular weight of 17.8 kDa, and had typical IR spectra characteristic of pectic polysaccharides. Antioxidant activities were investigated on the basis of ferric-reducing antioxidant power (FRAP), hydroxyl radical ( OH), 1,1-diphenyl-2-picrylhydrazyl radical (DPPH ) and superoxide radical ( O 2 − ) scavenging assay. TPPs-2-1 exhibited significant antioxidant activity in a concentration-dependent manner and might be exploited as effective natural antioxidant applied in functional food and medicine. [ABSTRACT FROM AUTHOR]

Polymers with different structures were isolated from the aboveground part of Heracleum sosnowskyi Manden. The sequential treatment of Heracleum with water, HCl solution, and (NH 4 ) 2 C 2 O 4 solution was observed to decrease the arabinogalactan proteins (AGP) content and increase the pectins content in the extracted polysaccharides. The linear region of the HS O -I polysaccharide having the highest yield was found to be composed mainly of partially methylesterified homogalacturonan fragments, whereas the branched region was made up of fragments of rhamnogalacturonan I whose core represents 1,2-α- l -rhamno-1,4-α- d -galacturonan. The carbohydrate side chains of the branched region are linked to the α- l -Rha p core residues via the 1,4-glycosidic bond and consist chiefly of T-β- d -Gal p , 1,4-β- d -Gal p and 1,6-β- d -Gal p residues indicating the presence of the 1,4-β- d -galactan. NMR spectroscopy revealed the carbohydrate moiety of the AGP molecule to consist mainly of 1,3- and 1,3,6-β- d -Gal p residues. The side chains comprised 1,6-β- d -Gal p , terminal 4- O -Me-β- d -Glc p A, and β- d -Gal p . [ABSTRACT FROM AUTHOR]

Silica aerogels are excellent thermal insulators, but their brittle nature has prevented widespread application. To overcome these mechanical limitations, silica–biopolymer hybrids are a promising alternative. A one-pot process to monolithic, superinsulating pectin–silica hybrid aerogels is presented. Their structural and physical properties can be tuned by adjusting the gelation pH and pectin concentration. Hybrid aerogels made at pH 1.5 exhibit minimal dust release and vastly improved mechanical properties while remaining excellent thermal insulators. The change in the mechanical properties is directly linked to the observed “neck-free” nanoscale network structure with thicker struts. Such a design is superior to “neck-limited”, classical inorganic aerogels. This new class of materials opens up new perspectives for novel silica–biopolymer nanocomposite aerogels. [ABSTRACT FROM AUTHOR]

The importance of common beans ( Phaseolus vulgaris ) in addressing food insecurity cannot be underestimated. However, their utilization is hampered by development of the hard-to-cook (HTC) defect, i.e., the inability of cotyledons to soften sufficiently within a reasonable time during cooking, the presence of flatulence causing oligosaccharides, the antinutrients and the low digestibility of macronutrients. The objective of this study was to determine the effect of storage conditions (time, temperature and relative humidity) on pectic polysaccharides of selected common bean varieties during the evolution of the hard cook problem. First, alcohol insoluble residue (AIR) was extracted from the bean flour. The AIR was fractionated into water, chelator and Na 2 CO 3 -soluble pectin fractions and a hemicellulose fraction. The galacturonic acid content, neutral sugars, degree of methylesterfication (DM), degree of acetylation (DAc) and molar mass distribution for pectin fractions were determined. In addition, filterable residual protein in various fractions was estimated. Results on the acidic and neutral sugars revealed that common beans contained highly branched, arabinose-rich pectic polysaccharides. Storage of common beans for more than 4 months at high relative humidity (83%) and high temperature (45 °C) resulting in HTC development showed a decrease in pectin extractability in water paralleled by an increase in the alkaline-soluble fraction. Other pectin characteristics such as DM and DAc showed minor variations upon storage of beans. The hydrolysis of both starch and proteins before AIR extraction decreased with increasing storage time, temperature and relative humidity. The increase in residual starch and protein might be linked to the protein–starch hypothesis where predominance of protein denaturation leads to restricted starch gelatinization. The results reveal that the contribution of pectic polysaccharides to development of HTC defect during the storage of Canadian wonder and Red haricot common beans at elevated temperature and relative humidity is due to reduced pectin solubility. However, the influence of starch and proteins seems evident. [ABSTRACT FROM AUTHOR]

BACKGROUND Green tea is a dietary source of bioactive compounds for human health. Enzymatic treatments induce the bioconversion of bioactive components, which can improve biological activities. In this study, we investigated the effect of simultaneous treatment with tannase and Rapidase on biotransformation of catechins and extraction of polysaccharide from green tea extract ( GTE). RESULTS Tannase and pectinase treatments induced the biotransformation of catechins and altered tea polysaccharide () content. The addition of GTE to the enzyme reaction resulted in a significant increase in degallated catechins, including gallic acid, a product of the tannase reaction (314.5-4076.0 µg mL−1) and a reduction in epigallocatechin gallate ( EGCG). Biotransformation of catechins improved the radical scavenging activity of GTE. Pectinase treatment led to change of TPS composition in GTE by hydrolyzing polysaccharides. In addition, pectinase-driven hydrolysis in polysaccharides significantly increased TPS-induced Interleukin 6 ( IL-6) production in macrophages. In particular, treatment of Rapidase ( TPS-Ra) led to the highest IL-6 production among TPS samples, similar to treatment of highly purified pectinase ( TPS-GTE), a positive control. CONCLUSION Simultaneous processing with tannase and Rapidase can be an efficient method for the extraction of bioactive polysaccharides and biotransformation of catechins with enhanced radical scavenging activity from green tea. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Structurally different pectins were isolated from the wood greenery of Abies sibirica L. by the sequential extraction with water (AS W ), HCl solution (pH∼4) (AS A ), and NH 3 solution (pH∼8.5) (AS N ). The GalA/Rha molar ratios for the AS W (15), AS A (8.9), and AS N (3.9) polysaccharides diminish in the order AS W > AS A > AS N , indicating a decrease in homogalacturonans and increase in rhamnogalacturonan I in this series. The AS W H, AS A H, and AS N H homogalacturonans derived by acid hydrolysis of AS W , AS A , and AS N have similar Mw 23.8, 21.1, and 18.9 kDa, respectively, corresponding to a mean polymerization degree of 97–122 for the GalA residue. The macromolecule backbone of AS N was represented mainly by moieties of partially methylesterified homogalacturonan and partially 2- O - and/or 3- O -acetylated rhamnogalacturonan I. The carbohydrate side chains of the branched region are primarily made up of terminal, 1,5- O -, 1,3,5-di- O - and 1,2,3,5-tri- O -substituted α-L-Ara f residues and terminal, 1,3- O - and 1,3,6-di- O -substituted β-D-Gal p residues. The currently known pectin models were refined. [ABSTRACT FROM AUTHOR]

In an attempt to develop a process of enzymatic peeling of mandarin segments suitable for use on an industrial scale, the cell wall fraction of the segment membrane of Satsuma mandarin fruits was extracted to obtain a chelating agent-soluble pectin fraction (ChSS), a dilute sodium hydroxide-soluble pectin fraction (DASS), a 1 M sodium hydroxide-soluble hemicellulose fraction (1MASS), a 4 M sodium hydroxide-soluble hemicellulose fraction (4MASS) and a cellulose-rich residue (3.1, 0.9, 0.4, 0.7 and 1.6% w/w of fresh membrane, respectively). The ChSS pectin consisted mainly of galacturonic acid followed by arabinose and galactose. The DASS fraction contained less galacturonic acid and more neutral sugars than ChSS. Eighty-nine percent of the galacturonic acid present in the segment membranes was recovered in the above two pectin fractions. The two hemicellulosic fractions consisted of two different molecular weight populations, which also differed in their sugar composition. Arabinose, xylose, mannose, galactose and glucose were the main sugar constituents of these hemicellulose fractions. In addition to an (arabino)xylan and a xyloglucan, the presence of an arabinogalactan is suggested by the sugar composition of both hemicelluloses. The pectin fractions were also characterised by their degradability by the pectic enzymes polygalacturonase, pectinmethylesterase and rhamnogalacturonan hydrolase. However the degree of degradation of the pectin fractions by enzymes differed, and the amount of the polymeric materials resistant to further degradation and the oligomeric products also differed. Using pectic enzymes it is possible to obtain peeled mandarin segments ready to eat or for canning. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the possibility of using mango endogenous pectinases to change the viscosity of mango purée. Hereto, the structure of pectic polysaccharide and the presence of sufficiently active endogenous enzymes of ripe mango were determined. Pectin of mango flesh had a high molecular weight and was highly methoxylated. Pectin methylesterase showed a negligible activity which is related to the confirmed presence of a pectin methylesterase inhibitor. Pectin contained relatively high amounts of galactose and considerable β-galactosidase (β-Gal) activity was observed. The possibility of stimulating β-Gal activity during processing (temperature/pressure, time) was investigated. β-Gal of mango was rather temperature labile but pressure stable relatively to the temperature and pressure levels used to inactivate destructive enzymes in industry. Creating processing conditions allowing endogenous β-Gal activity did not substantially change the consistency of mango purée. [ABSTRACT FROM AUTHOR]

To analyze the reliability of determining the weight fraction of protein in the samples of pectic polysaccharides by the optical density of solutions in the ultraviolet and visible regions of the spectrum, a comparison of eleven methods: Flores, Lowry, Bradford, Sedmac, Ruhemann (ninhydrin reaction) methods, ultraviolet spectrophotometry, methods with Benedict reagent, with Nessler reagent, with amide black, with bicinchoninate reagent, and the biuret method has been carried out. As a result, the insufficient sensitivity of seven of the listed methods has been found, which does not recommend them for these purposes. The Lowry, Bradford, Sedmac methods, and the method with the Nessler reagent can be used for the determination of protein content in the samples of pectic polysaccharides, and the Bradford method can be recommended for characterization of samples of pectic polysaccharides if the weight fraction of protein does not exceed 15%, and the Lowry method can be used for the samples with the weight fraction of protein greater than 15%. [ABSTRACT FROM AUTHOR]

A water soluble pectic polysaccharide (PS) isolated from the aqueous extract of the green fruits of Momordica charantia contains d -galactose and d -methyl galacturonate in a molar ratio of nearly 1:4. It showed splenocyte, thymocyte as well as macrophage activations . Moreover, it exhibited potent antioxidant activities. On the basis of total acid hydrolysis, methylation analysis, periodate oxidation, and 1D and 2D NMR studies, the structure of the repeating unit of the pectic polysaccharide was established as: [ABSTRACT FROM AUTHOR]

A polysaccharide fraction, HBE-III, was successfully purified in a high yield (40.4%) from its crude polysaccharide (HBE-0) which was prepared from pectinase hydrolysates of the peels of the Korean Citrus Hallabong. In experimental lung metastasis studies of Colon 26-M3.1 carcinoma cells, prophylactic administration of HBE-III significantly inhibited lung metastasis in a dose-dependent manner. In an in vitro cytotoxicity analysis, HBE-III (up to 1000 µg/mL) did not affect the growth of Colon 26-M3.1 cells and normal cells. HBE-III enhanced production of IL-6 and IL-12 by murine peritoneal macrophages. In an assay for natural killer (NK) cell activity, HBE-III (1000 µg/mouse, i.v.) significantly augmented NK cytotoxicity against Yac-1 tumor cells. The depletion of NK cells by injection of mouse anti-asialo GM1 serum abolished the inhibitory effect of HBE-III on lung metastasis of Colon 26-M3.1 cells. These data suggest that HBE-III may inhibit tumor metastasis via activation of macrophages and NK cells. [ABSTRACT FROM AUTHOR]

Recently, it has been suggested that pectinases could be used to hydrolyze pectin in biorefineries based on pectin-rich agro-industrial wastes. However, for this to be viable, the cost of their production would need to be lowered significantly. In fact, over the last few decades, there have been many attempts to improve pectinase production by existing strains or to screen for new strains from environmental isolates. In these studies, it is necessary to measure pectinase activities. Many researchers use single-time-point assays that involve incubation of pectinolytic extracts with pectic substrates for a fixed time, followed by determination of the liberated reducing sugars. However, different researchers use quite different conditions for this assay. Furthermore, no attention has been given to the reaction profile during the assay. In the current work, we show, for the first time, that a significant deceleration of the rate of liberation of reducing sugars occurs over the first ten minutes of the reaction. As a consequence, the incubation time used in a single-time-point assay has a large effect on the value obtained for the activity. In fact, we demonstrate that, depending on the particular combination of incubation time, pectin concentration and reaction temperature, the same extract could be reported to have activities that differ by an order of magnitude. In addition, we show that the relative activities obtained with polygalacturonic acid do not correlate with those obtained with pectin. We conclude that it is currently impossible to make meaningful comparisons between pectinase activities reported in the literature by workers who have used different assay conditions. Therefore there is an urgent need for the development of a standardized assay for evaluating the saccharification potential of pectinase complexes. [ABSTRACT FROM AUTHOR]

This review summarizes accumulated data about the structural organization of pectic macromolecules, including the latest developments in structural investigations of the molecular determinants of pectins, the existing models of pectic macromolecules, and several examples of pectins structure. Biological functions of pectic polysaccharides in a plant cell are described. The role of pectic polysaccharides as physiologically active components of the dietary fiber in nutrition is discussed and the data is given on their transformations in the digestive process. The effect of the structure of pectic polysaccharides on their gel forming ability is surveyed. The key issues are reviewed, which account for the importance of the further investigation of the structure and functional properties of pectins. [ABSTRACT FROM AUTHOR]

Changes in cell wall integrity upon thermal treatment were assessed in carrot cells using novel microscopic approaches using Congo red and different cell wall polysaccharide specific probes (JIM7, LM10, LM11, LM15, LM21, LM22 and CBM3a). Strong thermal processing induced an increased accessibility of cellulose and hemicelluloses by Congo red and the specific probes, except galactomannan, which detection was not affected by the thermal processing. Detection of pectin by JIM7 disappeared upon thermal processing, pointing at the leaching out effect of pectin from cell wall due to β-elimination. Changes observed after thermal processing were moreover similar to changes observed after enzymatic degradation of pectin, and a combination of thermal and pectinases treatments did not cause additional effects. These observations indicated that the presence of native pectin is the main factor governing cell wall polysaccharides accessibility and overall cell wall integrity in carrot, which can be modulated through thermal processing. [ABSTRACT FROM AUTHOR]

CPP1b is a pectic polysaccharide isolated from Codonopsis pilosula , and it possesses potent antitumor activity. In this study, a HNO 3 –Na 2 SeO 3 method was performed to synthesize selenium–CPP1b (sCPP1b). The effects of BaCl 2 usage amount and HNO 3 concentration on the yield and selenium content of sCPP1b were investigated by single-factor experiments. Reaction time, reaction temperature and the ratio of polysaccharide to Na 2 SeO 3 were optimized by orthogonal experimental design at three levels of each of the three factors (L 9 (3) 4 ) based on antitumor activity, selenium content and yield of sCPP1b. Our results showed that 5 h of reaction time, 60 °C of reaction temperature, and 2:2 ratio of polysaccharide to Na 2 SeO 3 were the optimal selenylation modification conditions. The validation experiments completed under the optimal conditions gave the mean selenium content and yield of sCPP1b were 478.17 μg/g (RSD = 5.7%) and 595 mg/g (RSD = 1.6%), respectively. Selenylation modification can significantly increase the antitumor activity of CPP1b in vitro . The structural characterization of sCPP1b was further characterized by Fourier-transform infrared spectroscopy, thermogravimetric analysis, and high-performance gel permeation chromatography coupled with multi-angle laser light scattering. These structure analysis results indicated that sCPP1b has been successfully selenylation modified with similar structure to polysaccharide of CPP1b. [ABSTRACT FROM AUTHOR]

Highlights: [•] A pectic polysaccharide was purified from Mosla chinensis Maxim. cv. Jiangxiangru. [•] Structural characterization of MP-A40 was elucidated by methylation and 1D/2D NMR. [•] The backbone of MP-A40 was 1,4-linked α-d-GalpA and 1,4-linked α-d-GalpA6Me (32%). [•] MP-A40 could inhibit the growth of K562 cells. [•] MP-A40 increased production of NO from RAW264.7 in a dose-dependent manner. [ABSTRACT FROM AUTHOR]

Highlights: [•] Chelator addition promoted increased pectinase catalyzed polysaccharide solubilization from pectinaceous biomass. [•] Chelator effects were in perfect agreement with their pK a and high calcium binding constants relative to galacturonic acid. [•] Potato pulp with reduced calcium content responded less to chelators and gave high enzymatic yields. [•] Chelating agents may assist the enzymatic release of pectinaceous structures by loosening the egg-box structures in homogalacturonan. [ABSTRACT FROM AUTHOR]

[Objective] To select the optimal extraction technology for the extraction of polysaccharides from black soybean by enzyme hydrolysis method. [Methods] The optimal enzyme was selected among cellulase, pectinase and papain. Effects of extraction temperature, extraction time, pH value and enzyme concentration were investigated. With the extraction rate of polysaccharides in black soybean as the evaluation index, the extraction parameters were optimized by asterion optimization design. [Results] Among the papain, cellulase and pectinase, cellulase showed the maximum extraction rate. The optimal extraction condition was as follows: pH 6.0, 0. 03 mg/mL enzyme concentration, 50 °C extraction tempeature and 120 min extraction time. [Conclusions] Under the optimal condition, the extraction rate of polysaccharides from black soybean was 0. 321 4%, which had 99.41% degree of closeness to the theoretical value. Factors affecting the extraction rate of polysaccharides from black soybean were in the order of pH value > extraction time > extraction tempeature. [ABSTRACT FROM AUTHOR]

Pectins are complex branched polysaccharides present in primary cell walls. As a distinctive feature, they contain high amount of partly methyl-esterified galacturonic acid and low amount of rhamnose and carry arabinose and galactose as major neutral sugars. Due to their structural complexity, they are modifiable by many different enzymes, including hydrolases, lyases, and esterases. Their peculiar structure is the origin of their physicochemical properties. Among others, their remarkable gelling properties make them a key additive for food industries. Pectin-degrading enzymes and -modifying enzymes may be used in a wide variety of applications to modulate pectin properties or produce pectin derivatives and oligosaccharides with functional as well as nutritional interests. This paper reviews the scientific information available on pectin structure, pectin-modifying enzymes, and the use of enzymes to produce pectin with controlled structure or pectin-derived oligosaccharides, with functional or nutritional interesting properties. [ABSTRACT FROM AUTHOR]