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ABSTRACT Bioelectrochemical systems (BESs) offer a sustainable method for chemical production, including the enhanced production of succinic acid. By combining fermentation with BES, it could be possible to achieve sustainable succinic acid production and CO2 fixation using Actinobacillus succinogenes. In literature, the potential application of BES is commonly associated with increased succinate yields, as it is expected to enhance the availability of NADH, thereby influencing the intracellular nicotinamide adenine dinucleotide (NADH/NAD+) balance. However, it remains unclear whether BES can improve NADH regeneration and achieve higher NADH/NAD+ ratios across all growth phases of A. succinogenes. This study investigates the impact of an applied electrical potential on the intracellular NADH/NAD+ ratio during an electrochemical‐assisted fermentation process. Using an adapted high‐performance liquid chromatography method with a Supelcosil LC‐18‐T column, it was demonstrated that NADH availability in BES, particularly during the stationary growth phase, improved by up to 1.98‐fold compared to the control. This enhancement in reducing power led to a succinate yield of 0.747 ± 0.01 g g−1, representing a 15.65% increase compared to a fermentation without electrochemical assistance. These findings support the expectation that the use of BES could enhance the competitiveness of bio‐based succinate production. [ABSTRACT FROM AUTHOR]

Diabetic wounds are usually entangled in a disorganized and self-perpetuating microenvironment and accompanied by a prolonged delay in tissue repair. Sustained and coordinated microenvironment regulation and tissue regeneration are key to the healing process of diabetic wounds, yet they continue to pose a formidable challenge. Here we report a rational double-layered dressing design based on chitosan and a degradable conjugated polymer polydiacetylene, poly(deca-4,6-diynedioic acid) (PDDA), that can meet this intricate requirement. With an alternating ene-yne backbone, PDDA degrades when reacting with various types of reactive oxygen species (ROS), and more importantly, generates proliferative succinic acid as a major degradant. Inheriting from PDDA, the developed PDDA-chitosan double layer dressing (PCD) can eliminate ROS in the microenvironment of diabetic wounds, alleviate inflammation, and downregulate gene expression of innate immune receptors. PCD degradation also triggers simultaneous release of succinic acid in a sustainable manner, enabling long-term promotion on tissue regeneration. We have validated the biocompatibility and excellent performance of PCD in expediting the wound healing on both diabetic mouse and porcine models, which underscores the significant translational potential of this microenvironment-modulating, growth-promoting wound dressing in diabetic wounds care. Sustained and coordinated microenvironment regulation and tissue regeneration are vital for the healing process of diabetic wounds but elusive. Here, the authors report a double-layered, microenvironment-modulating dressing able to eliminate reactive oxygen species and generate proliferative degradants that promote angiogenesis and tissue regeneration in diabetic wounds. [ABSTRACT FROM AUTHOR]

To meet the application requirements of electronic connectors, a trivalent chromium process (TCP) conversion coating was prepared on the Zn–Ni alloy plating of 2024 aluminium alloy. The composition of the TCP solution was as follows: 45 g/L Cr(NO3)3, 14 g/L CoCl2, 1.3 g/L NiCl2, 10 g/L citric acid, 10 g/L succinic acid and 1 g/L sodium dodecyl sulphate. The properties of TCP were characterised by a range of techniques, including macroscopic observations, scanning electron microscope, energy‐dispersive X‐ray spectrometer, three‐dimensional (3D) morphometry, electrochemical impedance spectroscopy, polarisation curves and conductivity tests. The TCP prepared in this experiment exhibits a uniform black colour and bright appearance, predominantly composed of Zn, Ni, O, Cr and Co. The TCP enhances the impedance of Zn–Ni alloys, reduces the corrosion current to 1.99 × 10−5 A/cm2 and maintains a flatter surface 3D morphology and less surface roughness following electrochemical testing. It has better corrosion resistance. Following the preparation of the TCP on a suitably sized shell sample, the shell resistance was 1.2 mVDC with good electrical conductivity, which meets the requirements for electrical connector applications. [ABSTRACT FROM AUTHOR]

Objectives: Dysbiosis of the skin microbiota has been identified as a key factor in the development of acne. This study was aimed to evaluate the effect of a facial cream gel containing a biotechnological phytocomplex, niacinamide and succinic acid on the bacterial diversity of subjects with mild–moderate acne and its clinical benefits due to microbiota changes. Methods: Open‐label, clinical study in 44 subjects with mild–moderate acne treated with a facial cream gel for 8 weeks. Bacterial diversity was analyzed by 16S rRNA gene sequencing of skin samples. Clinical effects were evaluated using the IGA acne severity scale, biometric measurements, and safety. Results: After 56 days of product's use, an increase in alpha and beta diversity was found (p < 0.01), with a decrease in the relative abundance of C. acnes (48.99% vs. 38.83%, p < 0.001). Regarding clinical results, a decrease in acne severity on the IGA scale (27.33%, p < 0.001), number of non‐inflammatory and inflammatory lesions (respectively: 31.12%, p = 0.05; 47.27%, p < 0.001), amount of sebum (89.00%, p < 0.01) and erythema (15.35%, p < 0.01), was found. [Correction added on 19 September 2024, after first online publication: In the preceding sentence, "42.27%" has been changed to "47.27%" in this version.] Responder analysis of the IGA score showed that 61.36% of patients improved by at least one point at day 56. The product was well tolerated throughout the study. Conclusions: The use of the facial cream gel on skin was effective in rebalancing the microbiota, inhibiting biofilm formation and other virulence factors, reducing the number of mild–moderate acne lesions and sebum secretion, and consequently improving acne's severity. [ABSTRACT FROM AUTHOR]

The legal obligation to swiftly adopt renewable energies has been increased because of the continuous usage of fossil fuels. In this perspective, biomass serves as a pillar to improve the current conditions over different heterogeneous catalysts due to their known advantages. This work is focused on the synthesis of a novel catalyst comprising mono lacunary phosphotungstate and zeolite HY. The catalyst was characterized by number of physicochemical techniques and evaluation of the activity of catalyst for the esterification of most promising bio platforms, levulinic acid and succinic acid to produce fuel additives. After a detailed optimization of both reactions, remarkable conversions of levulinic acid (77%) and succinic acid (96%) with turnover numbers of 2749 and 3427 respectively, were obtained. The order of the reaction and activation energy for the said reactions were calculated in the kinetic study. The sustainable nature of the catalyst was confirmed via regeneration and viability towards other bio-based molecules which enhances its industrial importance. [ABSTRACT FROM AUTHOR]

BACKGROUND: Yeast culture (YC) is a product fermented on a specific medium, which is a type of postbiotic of anaerobic solid‐state fermentation. Although YC has positive effects on the animal growth and health, it contains a variety of beneficial metabolites as dark matter, which have not been quantified. In the present study, liquid chromatography‐tandem mass spectrometry is employed to identify the unknown metabolites. Following their identification, the important chemicals are quantified using HPLC‐diode array detection methods. RESULTS: Non‐targeted metabolomics studies showed that 670 metabolites in total were identified in YC, of which 23 metabolites significantly increased, including organic acids, amino acids, nucleosides and purines, isoflavones, and other substances. The chemical quantitative analysis showed that the contents of succinic acid, aminobutyric acid, glutamine, purine and daidzein increased by 84.42%, 51.07%, 100%, 68.85% and 4.60%, respectively. CONCLUSION: Therefore, the use of non‐targeted metabolomics combined with chemical quantitative analysis to reveal the nutritional and functional substances of YC could help to elucidate the postbiotic mechanism and provide theoretical support for the regulation of the directional accumulation of beneficial metabolites. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: Polycystic ovary syndrome (PCOS) is a common heterogeneous disorder linked with endocrine and metabolic disturbances. The underlying mechanism of PCOS, especially its effect on oocyte competence, remains unclear. The study aimed to identify abnormal follicular metabolic changes using a multi-omics approach in follicular fluid from PCOS patients and to determine their effects on oocyte competence. Methods: A total of 36 women with PCOS and 35 women without PCOS who underwent in vitro fertilization and embryo transfer were included in the study. Cumulus cells and follicular fluid samples were collected. Follicular fluid samples underwent metabolomic analysis, while cumulus cell clusters from the same patients were assessed using transcriptomic analysis. Clinical information of patients and assisted reproductive technology (ART) results were recorded. Transcriptomics and metabolomics were integrated to identify disrupted pathways, and receiver operation characteristics (ROC) analysis was conducted to identify potential diagnostic biomarkers for PCOS. Pearson correlation analysis was conducted to assess the relationship between metabolites in follicular fluid and oocyte competence (fertilization and early embryo development potential). Results: Through multi-omics analysis, we identified aberrantly expressed pathways at both transcriptional and metabolic levels, such as the citrate cycle (TCA cycle), oxidative phosphorylation, the cAMP signaling pathway, the mTOR signaling pathway, and steroid hormone biosynthesis. Ten candidate metabolites were identified based on metabolic profiling data from these altered pathways. Phytic acid, succinic acid, 2'-deoxyinosine triphosphate, and 4- trimethylammoniobutanoic acid in the follicular fluid exhibited high specificity and sensitivity in distinguishing PCOS. Among these metabolites, L-arginine showed a negative correlation with the 2PN fertilization rate and cleavage rate, while estrone sulfate showed a negative correlation with the high-quality embryo rate in the in-vitro fertilization (IVF) cycle. Conclusions: We have conducted a preliminary study of a novel metabolic signature in women with PCOS using a multi-omics approach. The alterations in key metabolic pathways may enhance our understanding of the pathogenesis of PCOS. [ABSTRACT FROM AUTHOR]

Background: Succinic acid (SA) is an important bio-based C4 platform chemical with versatile applications, including the production of 1,4-butanediol, tetrahydrofuran, and γ-butyrolactone. The non-conventional yeast Yarrowia lipolytica has garnered substantial interest as a robust cell factory for SA production at low pH. However, the high concentrations of SA, especially under acidic conditions, can impose significant stress on microbial cells, leading to reduced glucose metabolism viability and compromised production performance. Therefore, it is important to develop Y. lipolytica strains with enhanced SA tolerance for industrial-scale SA production. Results: An SA-tolerant Y. lipolytica strain E501 with improved SA production was obtained through adaptive laboratory evolution (ALE). In a 5-L bioreactor, the evolved strain E501 produced 89.62 g/L SA, representing a 7.2% increase over the starting strain Hi-SA2. Genome resequencing and transcriptome analysis identified a mutation in the 26S proteasome regulatory subunit Rpn1, as well as genes involved in transmembrane transport, which may be associated with enhanced SA tolerance. By further fine-tuning the glycolytic pathway flux, the highest SA titer of 112.54 g/L to date at low pH was achieved, with a yield of 0.67 g/g glucose and a productivity of 2.08 g/L/h. Conclusion: This study provided a robust engineered Y. lipolytica strain capable of efficiently producing SA at low pH, thereby reducing the cost of industrial SA fermentation. [ABSTRACT FROM AUTHOR]

Plastic pollution, an increasingly serious global problem, can be addressed through the full lifecycle management of plastics, including plastics recycling as one of the most promising approaches. System design, catalyst development, and product separation are the keys in improving the economics of electrocatalytic plastics recycling. Here, a membrane‐free co‐production system was devised to produce succinic acid (SA) at both anode and cathode respectively by the co‐electrolysis of polybutylene succinate (PBS) waste plastics and biomass‐derived maleic acid (MA) for the first time. To this end, Cr3+‐Ni(OH)2 electrocatalyst featuring much enhanced 1,4‐butanediol (BDO) oxidation reaction (BOR) activity has been synthesized and the role of doped Cr has been revealed as an "electron puller" to accelerate the rate‐determining step (RDS) in the Ni2+/Ni3+ cycling. Impressively, an extra‐high SA production rate of 3.02 g h−1 and ultra‐high apparent Faraday efficiency towards SA (FEapparent=181.5 %) have been obtained. A carbon dioxide‐assisted sequential precipitation approach has been developed to produce high‐purity SA and byproduct NaHCO3 solids. Preliminary techno‐economic analysis demonstrates that the reported system is economically profitable and promising for future industrial applications. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA) was crosslinked with a homologous series of four different dicarboxylic acids, HOOC(CH2) n‐2COOH (n = 2 to 5) viz. oxalic acid (OA; C2), malonic acid (MA; C3), succinic acid (SA; C4) and glutaric acid (GA; C5) containing odd and even number of carbon atoms. The characterization and assessment of synthesized crosslinked films were done using ATR‐FTIR, XRD, SEM, AFM, DSC, rheology, percent swelling and sessile drop contact angle. The odd‐even effect of dicarboxylic acids was observed to significantly influence the physicochemical properties of PVA when employed as a crosslinker. PVA films crosslinked using dicarboxylic acids containing an even number of carbon atoms, displayed translucency, roughness, and an irregular matrix. In contrast, films incorporating an odd number of carbon atoms were transparent, homogenous, and densely packed. Furthermore, films containing even acids exhibited relatively lower crystallinity, lower melting temperature (Tm) and displayed an unexpected irregular trend in swelling as crosslinker concentration increased compared to films containing dicarboxylic acids with an odd number of carbon atoms which exhibits a consistent swelling with increasing crosslinker concentration. These results are attributed to the difference in the solubility and crystal structures of the odd‐even series of dicarboxylic acids. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Soft matrices with tuned properties are part of the vast landscape of innovative materials for the restoration of works of art. "Twin chain" polymer networks (TC‐PNs) based on polyvinyl alcohol have proven unique as scaffolds for Cultural Heritage cleaning. They enable optimum adaptability, adhesion, porosity, and connectivity at both micro‐ and nano‐scale resulting in superior time/space‐controlled cleaning operations. In this work, TC‐PNs properties are tuned through a mild crosslinking of the poly(vinyl alcohol) (PVA)‐porogen polymer by using sebacic, adipic, or succinic acid. The modified porogens have different structural features imparting a different phase behavior to TC‐PVAs mixtures in aqueous solution, i.e., in pre‐gel systems used to form gels through a liquid–liquid phase separation. The macro‐, micro‐, and nanoscale features of the final gels are characterized by Confocal Laser Scanning Microscopy, Small Angle X‐ray Scattering, Rheology and are related to their cleaning performances. The study shows that the gels cleaning capacity is related to their tortuosity, that can be tailored at the nanoscale. Counterintuitively gels with higher tortuosity show better performances as evidenced by the cleaning of mockups and paintings from Jean Helion, Jackson Pollock, and Tancredi Parmeggiani at Peggy Guggenheim Collection in Venice. [ABSTRACT FROM AUTHOR]

In this study, high-throughput sequencing (HTS) technology was used to investigate the composition and diversity of endophytic bacteria and their effects on succinic acid biosynthesis in P. ternata tubers from three different geographical locations (MS, SL, and ZT). A total of 1777 amplicon sequence variants (ASVs) were annotated, and the diversity and composition of endophytic bacteria in P. ternata tubers were significantly different among different regions. The ZT samples presented the highest α diversity, and the Shannon diversity, richness, and Pielou evenness index were all ZT > MS > SL. Co-occurrence network analysis revealed that endophytic bacterial groups such as Stenotrophomonas, Pseudomonas, Mycobacterium, and Chryseomicrobium were key groups in the endophytic bacterial interaction network, indicating that they play a role in maintaining community stability. In addition, some endophytic bacteria were associated with the biosynthesis of succinic acid, a key bioactive compound in P. ternata. The succinate content was positively correlated with the genera Brevundimonas, Ensifer, Nocardioides, and Paenibacillus, while it was negatively correlated with the genera Lentimicrobium, Anaerovorax, and Pajaroellobacter. These findings highlight the key role of endophytic bacteria in regulating the efficacy of P. ternata. These findings provide key information for further elucidating the mechanism by which endophytic bacteria affect the synthesis of bioactive compounds. [ABSTRACT FROM AUTHOR]

Artemisia abyssinica and Artemisia arborescens are unique plants that show significant bioactive properties and are used for the treatment of a variety of diseases. This study assessed the nutritional values, functional properties, chemical composition, and bioactive attributes of these plants as functional nutritional supplements. Compared to A. arborescens, A. abyssinica had higher fat (4.76%), fiber (16.07%), total carbohydrates (55.87%), and energy (302.15 kcal/100 g DW), along with superior functional properties, including higher water and oil absorption capacities (638.81% and 425.85%, respectively) and foaming capacity and stability (25.67% and 58.48%). The investigation of volatile compounds found that A. abyssinica had higher amounts of hotrienol (4.53%), yomogi alcohol (3.92%), caryophyllene (3.67%), and carvotanacetone (3.64%), which possess anti‐inflammatory, antimicrobial, and antioxidant properties. Artemisia abyssinica contributed over 30% of the recommended dietary intake (RDI) of amino acids. It displayed superior levels of sodium (31.46 mg/100 g DW) and calcium (238.07 mg/100 g DW). It also exhibited higher levels of organic acids, particularly malic acid, butyric acid, and succinic acid, compared to A. arborescens. Fatty acid analysis revealed palmitic and linoleic acids as primary components in both plants, with A. abyssinica having a higher palmitic acid content. Artemisia abyssinica also had higher vitamin C and thiamine levels. Although A. arborescens showed the highest total phenolic content (TPC), antioxidant activity, and capacity, A. abyssinica demonstrated acceptable efficiency in TPC and antioxidant content. These findings highlight the potential of both Artemisia species, particularly A. abyssinica, as valuable sources of nutrients and bioactive compounds for various applications. [ABSTRACT FROM AUTHOR]

In this study, two green extraction methods are explored to valorize rice straw into cellulose fibers (CFs), namely subcritical water extraction (SWE) and combined ultrasound‐heating treatment (USHT). The resultant fibers are, thereafter, successfully pretreated with (3‐glycidyloxypropyl) trimethoxysilane (GPS) and incorporated at 3% wt into poly(butylene succinate) (PBS) by melt‐mixing. The green composites are shaped into films by thermo‐compression and characterized in terms of their performance for food packaging applications. The chemical analysis of the fibers reveals that SWE is more effective to selectively remove hemicelluloses than USHT, whereas silanization promotes the removal of lignin in both fiber types. Fiber incorporation, more notably in the case of the silanized fibers, restricts the movement of the PBS chains, indicating good interaction with the biopolyester matrix. In particular, CFs act as antinucleating agents in PBS, delaying both glass transition and crystallization from the melt phenomena and hindering crystal formation. Furthermore, the fibers mechanically reinforce and improve the oxygen barrier of the PBS films. The highest barrier enhancement is obtained for the thermo‐compressed composite film with silanized fibers obtained by SWE, yielding a decrease of nearly 20% in the permeability to oxygen versus the unfilled PBS film. [ABSTRACT FROM AUTHOR]

Two ethanol-solvated adipate and succinate salts of carvedilol (CVD), a Biopharmaceutics Classification System class 2 drug, were synthesized by crystallizing ethanol with adipic acid (ADP) and succinic acid (SUA). Proton transfer from ADP and SUA to CVD and the presence of ethanol in the two novel compounds were confirmed using powder X-ray diffraction, Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and single-crystal X-ray diffraction measurements. The two novel ethanol-solvated salts exhibited enhanced solubility and dissolution rates compared with pure carvedilol in phosphate buffer (pH 6.8). Additionally, the morphologies and attachment energies of the two novel compounds and pure CVD were calculated based on their single-crystal structures, revealing a correlation between attachment energy and dissolution rate. [ABSTRACT FROM AUTHOR]

Under high humidity and high temperature conditions, the quality of pepper essential oil easily deteriorates, and the oxidation of oil restricts its application, especially for the insolubility in water. This study investigated pepper essential oil encapsulated in Pickering emulsion with octenyl succinic acid starch, which was effectively able to reduce 100 times of the release rate. The smooth surface and complete particles of the emulsion were observed and no new chemical bonds were formed. The minimum particle sizes were 2.05 µm and 1.89 µm, when the Pickering emulsion was set to different storage conditions at pH 5 and 0.1 M NaCl, respectively. During gastrointestinal digestion, the release of essential oils was effectively delayed in the Pickering emulsion and the digestibility of the emulsion was 16.93% in 120 min. Compared with untreated cells, Pickering emulsion can effectively inhibit the proliferation of MCF‐7 (52.71%). All these results indicate that OSA starch stabilized pepper essential oil can effectively increase solubility, improve stability, and expand the application range. Therefore, it can provide a theoretical basis for applications of pepper essential oil, especially for the functional drug application. [ABSTRACT FROM AUTHOR]

Mortierella alpina is popular for lipid production, but the low carbon conversion rate and lipid yield are major obstacles for its economic performance. Here, external addition of organic acids involved in tricarboxylic acid cycle was used to tune carbon flux and improve lipid production. Citrate was determined to be the best organic acid that can be used for enhancing lipid production. By the addition of citrate, the lipid titer and content were approximately 1.24 and 1.34 times higher, respectively. Meanwhile, citrate supplement also promoted the accumulation of succinate, an important value-added platform chemical. Owing to the improved lipid and succinate production through adding citrate, the carbon conversion rate of M. alpina reached up to 52.17%, much higher than that of the control group (14.11%). The addition of citrate could redistribute carbon flux by regulating the expression level of genes related to tricarboxylic acid cycle metabolism. More carbon fluxes flow to lipid and succinate synthesis, which greatly improved the carbon conversion efficiency of M. alpina. This study provides an effective and straightforward strategy with potential economic benefits to improve carbon conversion efficiency in M. alpina. [ABSTRACT FROM AUTHOR]

Dark chocolate presents exclusive characteristics that make it a food product with worldwide consumption and also as an ingredient in several food industries. Although chocolate is an energy-dense food, it is also rich in bioactive compounds and recent studies have demonstrated health benefits from a moderate consumption. Therefore, the quantification of the bioactive compounds of different types of cocoa, from different geographical origins, is of great importance to recognize the importance of single origin dark chocolate from the nutritional point of view. Dark chocolate produced from Amelonado variety presented higher values of hardness (5592 g), plastic viscosity (2.87 Pa.s) and yield value (12.91 Pa). Both dark chocolates from Peru, Piura Blanco and Chuncho, presented higher results in total phenolic content, total antioxidant capacity, caffeine and vitamin E. Additionally, sample Piura Blanco presented a higher content of theobromine (720.7 mg/100 g), lactic acid (1153.2 mg/100 g), succinic acid (679.4 mg/100 g) and oxalic acid (468.5 mg/100 g). On the other hand, chocolate from São Tomé presented a higher content of sucrose (38.22%) and SFA (62.38% of total fat). The results obtained demonstrate the existence of heterogeneity in cocoa varieties, supporting decision-makers in the selection of the most suitable cocoa for specific market needs. [ABSTRACT FROM AUTHOR]

Modern energy policies encourage the replacement of fossil fuels with a more sustainable type. Succinic acid is a promising renewable material that can react with ethylene glycol and 1,4‐butanediol in a two‐step polycondensation reaction to form hydroxylated polyesters. Copolymerization reactions were investigated to produce novel green binders for manufacture of solid propellants. The ester of the first step of polycondensation was used as a plasticizer in the propellant formulation. These products can be an alternative to binders of fossil sources, such as hydroxyl‐terminated polybutadiene (HTPB), frequently used as fuel of commercial propellants. Initially, analyses of Fourier transform infrared spectroscopy, nuclear magnetic resonance and gel permeation chromatography indicated the formation of polymeric products and adequate chain growth at reaction conditions. Then, the obtained copolymers were characterized by rheological analyses, which revealed that the processability of the copolymer materials was similar to that of the HTPB samples. Additionally, thermogravimetric analyses indicated that the copolymers presented good thermal stability below 200°C. Furthermore, differential scanning calorimetric (DSC) analyses indicated that the glass transition temperatures of the obtained copolymer samples ranged from −20 to −60°C, a suitable range for the intended use. Solid propellants were then prepared with solid loadings above 70 wt %, heat of combustion above 11,300 J g−1 and heat of explosion above 4,980 J g−1, which are compatible with values expected for solid propellants. Finally, oxygen balance calculations showed that the intrinsic oxygen content of the polyesters can allow the reduction of amounts of oxidizers in the final propellants. [ABSTRACT FROM AUTHOR]

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This work examines the electrochemically enhanced production of succinic acid using the bacterium Actinobacillus succinogenes. The principal objective is to enhance the metabolic potential of glucose and CO2 utilization via the C4 pathway in order to synthesize succinic acid. We report on the development of an electro-bioreactor system to increase succinic acid production in a power-2-X approach. The use of activated carbon fibers as electrode surfaces and contact areas allows A. succinogenes to self-initiate biofilm formation. The integration of an electrical potential into the system shifts the redox balance from NAD+ to NADH, increasing the efficiency of metabolic processes. Mediators such as neutral red facilitate electron transfer within the system and optimize the redox reactions that are crucial for increased succinic acid production. Furthermore, the role of carbon nanotubes (CNTs) in electron transfer was investigated. The electro-bioreactor system developed here was operated in batch mode for 48 h and showed improvements in succinic acid yield and concentration. In particular, a run with 100 µM neutral red and a voltage of −600 mV achieved a yield of 0.7 gsuccinate·gglucose−1. In the absence of neutral red, a higher yield of 0.72 gsuccinate·gglucose−1 was achieved, which represents an increase of 14% compared to the control. When a potential of −600 mV was used in conjunction with 500 µg∙L−1 CNTs, a 21% increase in succinate concentration was observed after 48 h. An increase of 33% was achieved in the same batch by increasing the stirring speed. These results underscore the potential of the electro-bioreactor system to markedly enhance succinic acid production. [ABSTRACT FROM AUTHOR]

Purpose: Azelnidipine, a BCS class II antihypertensive medication, is known for its low solubility and high permeability. In order to enhance its properties, generic GRAS (Generally Recognized as Safe) molecules were utilized in combination with crystal engineering to create novel cocrystal forms of azelnidipine. Methods: By varying the ratios (1:1, 1:2, and 2:1) and utilizing succinic acid and nicotinic acid as building blocks, pharmaceutical cocrystals of azelnidipine were successfully developed. A solvent ultrasonic technique was employed to synthesize these cocrystals, which were then subjected to various analytical techniques such as X-ray diffraction, differential scanning calorimetry, NMR, MASS, and FT-IR to confirm their purity, synthesize cocrystals, and evaluate their stability over a six-month period. X-ray crystal data revealed the characteristics of hydrogen bonding and interactions between the drug and co-formers, while differential scanning calorimetry highlighted differences in thermal behaviour and cocrystal formation. Results: Upon testing solubility and dissolution rate, it was observed that all cocrystals exhibited faster dissolution and higher equilibrium solubility compared to the parent medication. Among the cocrystals, those formed with succinic acid were found to be the most soluble form of azelnidipine. Conclusion: Overall, the development of pharmaceutical cocrystals of azelnidipine has shown promising results in enhancing the drug's solubility and dissolution rate, potentially leading to improved therapeutic outcomes. [ABSTRACT FROM AUTHOR]

The composition of aerosols influenced by regional pollution sources during a post-monsoon haze event was studied including the isotopic, bulk, and molecular signatures. The air mass back trajectory and fire spot analysis revealed that the Delhi aerosols were influenced by the regional post-harvest crop (rice plant) residue-burning activities during the sampling period. To better understand the atmospheric processes during such an event, three samples of 4 h duration each (Period I: from 06:00–10:00, Period II: 10:00–14:00, and Period III: 14:00–18:00 h local time) were collected during the sampling period (8th -17th November, 2019) in the daytime. The average mass concentration of PM2.5, molecular compounds including the inorganic and carbonaceous components (dicarboxylic acid class compounds), along with the stable isotopes of C and N were observed to be elevated during Period I of the study. NH4+ and SO42− were found to be the most abundant inorganic ions during Period II and III with Cl− being the dominant ion during Period I. The OC/EC, WSOC/EC ratios indicated the influence of biomass burning on Delhi aerosols with little influence of local ageing processes evident from the minimal variation observed between the three periods of study during the day. High concentrations of dicarboxylic acids than previous studies are reported with oxalic and succinic acid being the most abundant diacids, a typical behaviour observed in biomass-burning influenced aerosols with an interesting observation of terephthalic acid to be found in an appreciable amount. The δ15 N of TN and δ13 C of TC signatures clearly indicated the influence of emissions from the burning of a C3 plant on the aerosols. The results strongly suggested that the aerosols were influenced by biomass-burning activities in the neighbouring regions and were aged during the atmospheric transport over to the city of Delhi with minimal effect of local ageing processes during the study period. [ABSTRACT FROM AUTHOR]

Alumoxanes are typically produced via controlled hydrolysis of short‐chain alkyl aluminium compounds which leads to oligomeric species that are usually difficult to obtain in crystalline form. Simultaneously, various alternative non‐hydrolytic approaches to alumoxanes have also been used. In this work, we report on a new methylalumoxane scaffold derived from the alkylation of a series of dicarboxylic acids: itaconic acid (HO2CCH2C(=CH2)CO2H), succinic acid (HO2CCH2CH2CO2H) and homophthalic acid (HO2CCH2C6H4CO2H). The reactions of AlMe3 with a selected dicarboxylic acid in the molar ratio 4 : 1 conducted at elevated temperature occur with double methylation of each carboxylic group and provide to the formation of a new methylalumoxane aggregate, Me10Al6O4, flanked by methylaluminium diolate units. We also aimed to obtain dialkylaluminium derivatives of dicarboxylic acids by the controlled reaction of the appropriate acid with AlMe3 in the 1 : 2 stoichiometry. While the synthesis of organoaluminium derivatives of flexible aliphatic dicarboxylic acids (itaconic and succinic acids) is challenging due to their insolubility, the related homophtalate compound readily forms a molecular tetranuclear cluster, [([(O2CCH2C6H4CO2)(μ‐AlMe2)2]2. The molecular and crystal structures of the resulting compounds were determined via NMR spectroscopic analysis and single crystal X‐ray diffraction crystallography. [ABSTRACT FROM AUTHOR]

Simple Summary: Plant extracts have emerged as a viable alternative to antibiotics in livestock production, contributing to the sustainable development of modern animal husbandry. Among these extracts, tea polyphenols, derived from tea leaves as polyhydroxyphenolic compounds, exhibit diverse bioactive properties. This study aimed to assess the impact of tea polyphenols on serum parameters, rumen microbiota, rumen metabolism, and liver metabolism in Hu sheep. The results indicated that dietary supplementation with tea polyphenols did not significantly affect the serum physiological indices of the sheep but enhanced serum immunity and antioxidant levels. Moreover, Firmicutes dominated the network map of the top 80 abundant microorganisms at the genus level, identifying 13 biomarkers at the genus level. Furthermore, tea polyphenols have been found to modulate both rumen and liver metabolism, particularly in relation to energy and lipid metabolism. Furthermore, strong correlations were observed between liver and rumen metabolites, particularly between rumen succinic acid and liver alanyl−serine and methylmalonic acid. This establishes a theoretical basis for tea polyphenol applications and suggests directions for optimizing future additive dosages. This study investigated the impact of tea polyphenols on serum indices, rumen microorganisms, rumen metabolism, and liver metabolism in Hu sheep. Sixty healthy lambs, aged three months and with similar average weights, were chosen and randomly assigned to control (CON), TP400, TP800, and TP1200 groups, each consisting of fifteen lambs. The control group received a basal diet, while the experimental groups were provided with basal diet supplemented with 400 mg/kg, 800 mg/kg, and 1200 mg/kg of tea polyphenols, respectively. Compared with the CON group, the addition of tea polyphenols to the diet significantly increased serum IgA, GSH−Px, and TSOD. In addition, tea polyphenols were able to increase rumen pH but had no significant effect on the rumen NH3−N, VFA molar content, and the microbial top 10 phylum and genus levels. Moreover, Firmicutes predominated in the network map of the top 80 abundant microorganisms at the genus level, identifying 13 biomarkers at the genus level. In addition, strong correlations were observed between liver and rumen metabolites, particularly between rumen succinic acid and liver alanyl−serine and methylmalonic acid. Furthermore, tea polyphenol additions changed the enrichment of liver and rumen metabolites in the top five KEGG metabolic pathways, but 400−1200 mg/kg additions had no negative impact on the liver and rumen. In summary, TP significantly influences rumen and liver metabolites in Hu sheep, enhancing lamb immunity and antioxidant capacity, with 400 mg/kg being the most effective dosage. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Succinic acid (SA), a dicarboxylic acid of industrial importance, can be efficiently produced by metabolically engineered Mannheimia succiniciproducens. Although the importance of magnesium (Mg2+) ion on SA production has been evident from our previous studies, the role of Mg2+ ion remains largely unexplored. In this study, we investigated the impact of Mg2+ ion on SA production and developed a hyper-SA producing strain of M. succiniciproducens by reconstructing the Mg2+ ion transport system. To achieve this, optimal alkaline neutralizer comprising Mg2+ ion was developed and the physiological effect of Mg2+ ion was analyzed. Subsequently, the Mg2+ ion transport system was reconstructed by introducing an efficient Mg2+ ion transporter from Salmonella enterica. A high-inoculum fed-batch fermentation of the final engineered strain produced 152.23 ± 0.99 g/L of SA, with a maximum productivity of 39.64 ± 0.69 g/L/h. These findings highlight the importance of Mg2+ ions and transportation system optimization in succinic acid production by M. succiniciproducens. [ABSTRACT FROM AUTHOR]

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Using a new red blood cell (RBC) metabolite extraction protocol, we performed a metabolomic analysis on RBCs in rheumatoid arthritis (RA) patients treated or not with methotrexate (MTX), with the two following objectives: to compare the RBC metabolic profiles of MTX-naïve RA patients and healthy controls (HC), and to investigate whether RBC profiles before and after MTX treatment in RA differed between responders and non-responders. Plasma analysis was performed in parallel. Metabolites were extracted and identified in RBCs and plasma by liquid chromatography-mass spectrometry. We compared the metabolomic fingerprints of 31 DMARD-naïve RA patients and 39 HCs. We also compared the RBC and plasma metabolomes of 25 RA patients who responded or not to MTX therapy before (M0) and after a 3-month treatment period (M3). Significance was determined by Storey's false discovery rate (FDR) q-values to correct for multiple testing. RA patients and HCs differed in the metabolomic signature of RBCs. The signature mainly contained amino acids (AA). Eleven metabolites, including 4 metabolites belonging to the carbohydrate subclass and 2 amino acids (creatine and valine) showed accumulation in RBCs from RA patients. Conversely, citrulline (fold change = 0.83; q = 0.025), histidine (fold change = 0.86; q = 0.014) and ergothioneine (EGT) (fold change = 0.66; q = 0.024), were lower in RBC of RA patients. Five plasma metabolites, including succinic acid and hydroxyproline, were higher in RA patients, and 7 metabolites, including DHEA sulfate, alanine, threonine and ornithine, were lower. Among RA patients undergoing MTX treatment pre-treatment (M0), EGT values were significantly lower in non-responders. In conclusion, low RBC levels of EGT, a food-derived AA barely detectable in plasma, characterize DMARD naïve RA patients and lack of response to MTX treatment. [ABSTRACT FROM AUTHOR]

Facing complex and variable emerging antibiotic pollutants, the traditional development of functional materials is a "trial-and-error" process based on physicochemical principles, where laborious steps and long timescales make it difficult to accelerate technical breakthroughs. Notably, natural biomolecular coronas derived from highly tolerant organisms under significant contamination scenarios can be used in conjunction with nanotechnology to tackling emerging contaminants of concern. Here, super worms (Tubifex tubifex) with high pollutant tolerance were integrated with nano-zero valent iron (nZVI) to effectively reduce the content of 17 antibiotics in wastewater within 7 d. Inspired by the synergistic remediation, nZVI-augmented worms were constructed as biological nanocomposites. Neither nZVI (0.3 to 3 g/L) nor worms (104 to 105 per liter) alone efficiently degraded florfenicol (FF, as a representative antibiotic), while their composite removed 87% of FF (3 µmol/L). Under antibiotic exposure, biomolecules secreted by worms formed a corona on and modified the nZVI particle surface, enabling the nano-bio interface greater functionality, including responsiveness, enrichment, and reduction. Mechanistically, FF exposure activated glucose-alanine cycle pathways that synthesize organic acids and amines as major metabolites, which were assembled into vesicles and secreted, thereby interacting with nZVI in a biologically response design strategy. Lactic acid and urea formed hydrogen bonds with FF, enriched analyte presence at the heterogeneous interface. Succinic and lactic acids corroded the nZVI passivation layer and promoted electron transfer through surface conjugation. This unique strategy highlights biomolecular coronas as a complex resource to augment nano-enabled technologies and will provide shortcuts for rational manipulation of nanomaterial surfaces with coordinated multifunctionalities. [ABSTRACT FROM AUTHOR]

The present study demonstrates that low concentrations of azelaic acid (AZA) significantly impact the metabolism of Arabidopsis thaliana seedlings, leading to imbalances in numerous minerals and metabolites due to AZA‐induced stress. Untargeted metabolomic analyses were conducted on untreated and AZA‐treated seedlings at two time points: 7 and 14 days after treatment initiation. The results revealed a general accumulation of sugars (e.g., glucose, mannose, xylose), amino acids (e.g., lysine, GABA, threonine, glutamine), and organic acids (e.g., glutaric acid, shikimic acid, succinic acid) in AZA treated‐seedlings, suggesting that AZA triggers stress responses in Arabidopsis. Ionomic analysis revealed that AZA induces phosphorus deficiency, which plants compensate by increasing malate content in the roots. Additionally, AZA treatment induced putrescine accumulation within the root, a metabolic biomarker of potassium deficiency and plant stress. The metabolomic profile showed elevated levels of different specialized metabolites, such as nitrogen‐ and sulphur‐containing compounds, and altered levels of various phytohormones, including jasmonates and brassinosteroids, implicated in plant protection under biotic and/or abiotic stresses. These findings support the hypothesis that AZA's mode of action is associated with an auxin imbalance, suggesting its function as an auxinic herbicide. The observed increases in starch and jasmonates, coupled with the disruptions in potassium homeostasis, are linked to the previously reported alterations in the auxin transport, root architecture and gravitropic root response. Statistical analyses were applied, including Kruskal‐Wallis tests for ionomic data, as well as multifactor analysis, Principal Component Analysis, Orthogonal Partial Least Squares‐Discriminant Analysis, and enrichment pathway analysis for metabolomic data, ensuring the robustness and validity of these findings. [ABSTRACT FROM AUTHOR]

In order to improve the efficiency of crude oil recovery, reduce the adhesion and adsorption of crude oil in the formation, reduce the interfacial tension of oil and water to form a stable emulsion, the performance evaluation of new surfactants and methods for improving oil recovery are studied. The esterification reaction is used to synthesize the raw material of glyceryl monooleate succinic acid monoester, and the raw material is neutralized with an alkaline solution to prepare a new surfactant. Through experiments, the surfactant's interfacial tension, salt resistance, temperature resistance, emulsification, viscosity reduction and other properties were evaluated, and the effect of changing the oil recovery rate after using the surfactant was studied. Test results show that this new surfactant can significantly reduce the water-oil interfacial tension, and can still reduce the water-oil interfacial tension even in saline environments and high temperature environments. After the temperature reaches 50°C, the temperature resistance is basically stable; When the surfactant concentration of the water-oil ratio is lower than 7:3 and higher than 700mk/L, it can reduce the viscosity of the water-oil mixture; the surfactant has good foam performance and emulsification, and can effectively improve crude oil recovery. Use 0.25% mass fraction surfactant, can effectively improve oil recovery, but abnormal low-pressure environment will affect the recovery effect. [ABSTRACT FROM AUTHOR]

A synthetic method for betulin 3-O-propionate 28-O-acylates via the reaction of betulin 3-O-propionate with melts of benzoic, phthalic, cinnamic, and succinic acids at 185–195°C for 5–6 min was proposed. [ABSTRACT FROM AUTHOR]

Mushrooms have been essential to the human diet because they contain balanced chemical components and some biologically active substances. In this work, we investigated the phenolics, essential oils, metal contents, antioxidant, antibacterial, DNA protective, and enzyme inhibition activities for Clitocybe geotropa, Ramaria aurea, Rhizopogon luteolus (RL), Russula delica (RD), Verpa bohemica, and Marasmius oreades mushrooms. Results exhibited a higher content for citric and succinic acids in all tested kinds. Further, we detected a high content of cis‐9‐oleic acid, linoleate, and cis‐11‐eicosanoate. All mushroom species contain a significant percentage of both Cu and Zn. Moreover, RL and RD recorded the highest phenolic and flavonoid contents. Furthermore, all samples showed standard to good antioxidant activity, and the same is true for the antibacterial and DNA protective activities. Enzyme inhibition activity was generally high and significantly higher against the urease than the thiourea. We applied molecular docking between the highest phenolic molecules with the urease to determine the mushroom extracts' high inhibition mechanism. In conclusion, all mushroom species revealed a variety in chemical content that is probably related to their multi‐bioactivity. [ABSTRACT FROM AUTHOR]

Small α-dicarbonyl compounds like succinic acid are found abundantly in the atmosphere, thereby contributing to the formation of secondary organic aerosols through solid or liquid particles and gas-phase molecular clusters. The vibrational spectrum of succinic acid was measured in two different environments to evidence the role of the medium on the geometry adopted by the acid. Different structures were observed. The planar and extended structures of succinic acid were favored in the solid state whereas the non-planar gauche conformer was the predominant form in an argon matrix at 20 K, similar to the gas phase. Aided by quantum chemistry calculations and the non-covalent interactions analysis, we investigated the conformational diversity of succinic acid to understand the factors that govern the stability of the acid. [ABSTRACT FROM AUTHOR]

Succinic acid is recognized as a key component in the production of various commercially important chemical commodities. Technical‐economic analysis can provide valuable insights into the feasibility of large‐scale biochemical production of succinic acid. In this study, the effects of scale on the design of a biorefinery using sugarcane bagasse were evaluated using a detailed process modeling methodology. Four processes were simulated and compared, three based on patents from biosuccinic acid (bio‐SA) manufacturing companies and one based on a process economic program report (PEP). This methodology allowed for the analysis of scale benefits for each technological route. A comprehensive economic evaluation was conducted by comparing the biochemical processes in terms of investment and production costs, as well as the minimum selling price (MSP) of bio‐SA. Results show that the MSP of more promising process designs ranged from 3105 to 2095 $ t−1, which is compatible with the cost of petrochemical‐based succinic acid. Moreover, for capacities above 90 kt year−1, the MSP remains virtually constant, and every process evaluated revealed a breakdown in the project economy of scale. A sensitivity and risk analysis was carried out to evaluate the impacts of several process parameters on the project's technoeconomic analysis, resulting in bio‐SA selling price and investment costs as parameters with the highest impact on economic viability. [ABSTRACT FROM AUTHOR]

• Succinic acid production of 30 g/L was shown with 6 gC/L MgCO3 and 24 gC/L glucose. • The inorganic carbon of "carbonate:CO2 = 1:9″ presented the highest CO2 fixation. • The PEPCK/LDH was enhanced at high gaseous CO2, by promoting succinic acid path. • 50%−65% of inorganic carbon utilization was increased via stepwise CO2 addition. • 20%−30% increment in succinic acid selectivity was shown via stepwise CO2 addition. Utilizing CO 2 for bio-succinic acid production is an attractive approach to achieve carbon capture and recycling (CCR) with simultaneous production of a useful platform chemical. Actinobacillus succinogenes and Basfia succiniciproducens were selected and investigated as microbial catalysts. Firstly, the type and concentration of inorganic carbon concentration and glucose concentration were evaluated. 6 g C/L MgCO 3 and 24 g C/L glucose were found to be the optimal basic operational conditions, with succinic acid production and carbon yield of over 30 g/L and over 40%, respectively. Then, for maximum gaseous CO 2 fixation, carbonate was replaced with CO 2 at different ratios. The "less carbonate more CO 2 " condition of the inorganic carbon source was set as carbonate: CO 2 = 1:9 (based on the mass of carbon). This condition presented the highest availability of CO 2 by well-balanced chemical reaction equilibrium and phase equilibrium, showing the best performance with regarding CO 2 fixation (about 15 mg C/(L·hr)), with suppressed lactic acid accumulation. According to key enzymes analysis, the ratio of phosphoenolpyruvate carboxykinase to lactic dehydrogenase was enhanced at high ratios of gaseous CO 2 , which could promote glucose conversion through the succinic acid path. To further increase gaseous CO 2 fixation and succinic acid production and selectivity, stepwise CO 2 addition was evaluated. 50%-65% increase in inorganic carbon utilization was obtained coupled with 20%-30% increase in succinic acid selectivity. This was due to the promotion of the succinic acid branch of the glucose metabolism, while suppressing the pyruvate branch, along with the inhibition on the conversion from glucose to lactic acid. [Display omitted] [ABSTRACT FROM AUTHOR]

Environmental issues, including climate change and plastic pollution, have compelled scientists to look at alternatives to traditional polymers. Scientists are actively researching biobased hyperbranched polymers, an emerging group of highly branched polymers made from sustainable resources. They are seen as a promising alternative to petrochemical-based polymers. Hyperbranched polymers can be made using single- and double-monomer techniques. This review provides an extensive perspective of the synthesis and properties of biobased hyperbranched polymers made from a variety of renewable starting materials, including starch, lignin, vanillin, levulinic acid, furfurylamine, ferulic acid, citric acid, adipic acid, succinic acid, and tannic acid and various vegetable oils have been investigated till date. Most of these biobased hyperbranched polymers have been created using vegetable oil as their raw materials because numerous vegetable oil derivatives like monoglycerides, polyols, and fatty acids can be potentially used as monomers for the polymer. In the paper, specifics about modified biobased hyperbranched polymers, their composites, nanocomposites, and functionalized versions are highlighted. These materials belong to a class that combines the special characteristics of hyperbranched polymers with the reinforcing and functionalizing effects of fillers like silver, carbon, silicone, clay, etc. Lastly, the paper also discusses the various practical applications of biobased hyperbranched polymers in various industrial sectors and their prospects for the future. [ABSTRACT FROM AUTHOR]

In the present study, green -stretchable ‎ hydrogels based on succinic acid were prepared. Green monomers based on bio-acid were identified using the compression reaction between an acidic group and an alcoholic group and using 1H NMR and FT-IR. The results showed the preparation of flexible stretchable hydrogel with high swelling capacity (7050%) and suitable rheological behavior. The surface morphology and antibacterial behavior of hydrogels were also investigated through SEM and optical density methods, respectively. Examining the results of these tests confirmed the preparation of hydrogel with suitable porosity for biomedical applications and favorable antibacterial properties (Antibacterial efficiency > 77%). [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chinese Institute of Food Science & Technology / Zhongguo Shipin Xuebao is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Acetobacter syzygii CCTCC M 2022983 was isolated and characterized from Tibetan kefir grains, which is utilized as a functional food with diverse bioactive properties. After 6 days of fermentation by A. syzygii, Acetobacter fermented extract (AFE) showed significantly higher antioxidant, anti-tyrosinase, and anti-melanin effects compared to the unfermented yeast extract (UFY). Western blotting confirmed that AFE reduced melanogenesis-related proteins (MITF, TYR, TRP-1, TRP-2). LC-MS/MS analysis identified 4-hydroxybenzoic acid as abundant in AFE, contributing to its antioxidant capacity. Succinic acid and citric acid emerged as the major compound and a type of mixed inhibitor against mushroom tyrosinase, with IC50 values of 2.943 mM and 1.615 mM, respectively. Fluorescence spectra analysis revealed that these acids caused conformational changes in tyrosinase. Moreover, succinic acid and citric acid prevented L-DOPA from auto-oxidation with IC50 values of 0.355 mM and 0.261 mM, respectively. Molecular docking analysis suggested that these acids interacted with the association of the H and L subunits of tyrosinase, thereby reducing its stability. In B16-F10 cells, succinic and citric acids significantly reduced melanin production in a dose-dependent manner. Thus, succinic acid and citric acid revealed promising potential for applications in the food and medicine industries as melanogenesis inhibitors due to their safety. [ABSTRACT FROM AUTHOR]

In recent years, thermoset elastomers, particularly polyesters derived from the polycondensation of glycerol and non-toxic diacids, have garnered significant interest. This study focuses on the synthesis of poly(glycerol-co-diacids) polymers using varying molar ratios of glycerol (G), sebacic acid (S), and succinic acid (Su). Seven distinct ratios were investigated (PGS (1:1), PGSSu (1:0.9:0.1), PGSSu (1:0.8:0.2), PGSSu (1:0.5:0.5), PGSSu (1:0.2:0.8), PGSSu (1:0.1:0.9) and PGSu (1:1)). The resulting polymers were analyzed using Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), dynamic mechanical analyses (DMA), tensile tests, scanning electron microscopy (SEM), gel fraction and degree of swelling determination. Among the synthesized polymers, PGS (1:1) and PGSu (1:1) exhibited superior mechanical robustness than the polymers obtained by mixing diacids. The results show that the incorporation of succinic acid in the synthesis of the polymers progressively led to rougher surfaces and a reduction in thermal resistance compared to PGS (1:1). PGSu (1:1) showed the highest surface roughness and the lowest thermal resistance. The glass transition temperature (Tg) for these elastomers ranged from − 30 °C to 30 °C. Additionally, higher ratios of succinic acid led to increased polymer density and less degree of swelling. The gel fraction of these polymers ranged from 70 to 95%. PGS (1:1) with the lowest and PGSu (1:1) with the highest gel fraction, respectively. [ABSTRACT FROM AUTHOR]

Background: In the treatment of oncological diseases in children, the search for opportunities for the earlier detection of complications to improve treatment results is very important. Metabolomic studies are actively conducted to stratify different groups of patients in order to identify the most promising markers. Methods: Three groups of patients participated in this study: healthy children as a control group (n = 18), children with various malignant oncological diseases (leukemia, lymphoma, nephroblastoma, ependymoma, etc.) as patients (n = 40) without complications, and patients (n = 31) with complications (inflammatory and infectious). The mitochondrial metabolites (succinic and fumaric acids); biomarkers related to inflammation such as C-reactive protein (CRP), procalcitonin (PCT), and presepsin (PSP); and sepsis-associated aromatic metabolites, such as phenyllactic (PhLA), hydroxyphenyllactic (p-HPhLA), and hydroxyphenylacetic acids (p-HPhAA), were identified. Results: It was found that children with malignant oncological diseases had profound metabolic dysfunction compared to healthy children, regardless of the presence of systemic inflammatory response syndrome (SIRS) or sepsis. The prognostic ability of procalcitonin and presepsin for detecting sepsis was high: AUROC = 0.875, cut-off value (Youden index) = 0.913 ng/mL, and AUROC = 0.774, with cut-off value (Youden index) of 526 pg/mL, respectively. Conclusions: A significant increase in aromatic microbial metabolites and biomarkers in non-survivor patients that is registered already in the first days of the development of complications indicates the appropriateness of assessing metabolic dysfunction for its timely targeted correction. [ABSTRACT FROM AUTHOR]

(1) Background: Osteoarthritis (OA) is a heterogeneous disorder, and subgroup classification of OA remains elusive. The aim of our study was to identify endotypes of hip OA and investigate the altered pathways in the different endotypes. (2) Methods: Metabolomic profiling and genome-wide genotyping were performed on fasting blood. Transcriptomic profiling was performed on RNA extracted from cartilage samples. Machine learning methods were used to identify endotypes of hip OA. Pathway analysis was used to identify the altered pathways between hip endotypes and controls. GWAS was performed on each of the identified metabolites. Transcriptomic data was used to examine the expression levels of identified genes in cartilage. (3) Results: 180 hip OA patients and 120 OA-free controls were classified into three clusters based on metabolomic data. The combination of arginine, ornithine, and the average value of 7 lysophosphatidylcholines had an area under the curve (AUC) of 0.97 (95% CI: 0.96–0.99) to discriminate hip OA from controls, and the combination of γ-aminobutyric acid, spermine, aconitic acid, and succinic acid had an AUC of 0.96 (95% CI: 0.94–0.99) to distinguish two hip OA endotypes. GWAS identified 236 SNPs to be associated with identified metabolites at GWAS significance level. Pro-inflammatory cytokine levels were significantly different between two endotypes (all p < 0.05). (4) Conclusions: Hip OA could be classified into two distinct molecular endotypes. The primary differences between the two endotypes involve changes in pro-inflammatory factors and energy metabolism. [ABSTRACT FROM AUTHOR]

Abstract Background Succinic acid (SA) is an important bio-based C4 platform chemical with versatile applications, including the production of 1,4-butanediol, tetrahydrofuran, and γ-butyrolactone. The non-conventional yeast Yarrowia lipolytica has garnered substantial interest as a robust cell factory for SA production at low pH. However, the high concentrations of SA, especially under acidic conditions, can impose significant stress on microbial cells, leading to reduced glucose metabolism viability and compromised production performance. Therefore, it is important to develop Y. lipolytica strains with enhanced SA tolerance for industrial-scale SA production. Results An SA-tolerant Y. lipolytica strain E501 with improved SA production was obtained through adaptive laboratory evolution (ALE). In a 5-L bioreactor, the evolved strain E501 produced 89.62 g/L SA, representing a 7.2% increase over the starting strain Hi-SA2. Genome resequencing and transcriptome analysis identified a mutation in the 26S proteasome regulatory subunit Rpn1, as well as genes involved in transmembrane transport, which may be associated with enhanced SA tolerance. By further fine-tuning the glycolytic pathway flux, the highest SA titer of 112.54 g/L to date at low pH was achieved, with a yield of 0.67 g/g glucose and a productivity of 2.08 g/L/h. Conclusion This study provided a robust engineered Y. lipolytica strain capable of efficiently producing SA at low pH, thereby reducing the cost of industrial SA fermentation. Graphical abstract

To evaluate the effects of dietary supplementation with succinic acid on growth performance, flesh quality, glucose, and lipid metabolism of Nile tilapia (Oreochromis niloticus) fed a high-carbohydrate diet (HCD), five iso-nitrogenous and iso-lipidic diets were prepared as follows: HCD (control group) consisting of 55% corn starch and HCD supplemented with 0.5%, 1.0%, 2.0%, and 4.0% succinic acid, respectively. Tilapia with an initial body weight of 204.90 ± 1.23 g randomly assigned to 15 tanks with 3 replicates per group and 10 fish per tank fed for 8 weeks. Increasing dietary succinic acid supplementation resulted in significant second-order polynomial relationship in the weight gain rate (WGR), specific growth rate (SGR), feed conversion ratio (FCR), protein efficiency rate (PER), viscerosomatic index, condition factor, and contents of muscular crude lipid and glycogen (P

Propionate is a microbial metabolite formed in the gastrointestinal tract, and it affects host physiology as a source of energy and signaling molecule. Despite the importance of propionate, the biochemical pathways responsible for its formation are not clear in all microbes. For the succinate pathway used during fermentation, a key enzyme appears to be missing-one that oxidizes ferredoxin and reduces NAD. Here we show that Rnf [ferredoxin-NAD+ oxidoreductase (Na+-transporting)] is this key enzyme in two abundant bacteria of the rumen (Prevotella brevis and Prevotella ruminicola). We found these bacteria form propionate, succinate, and acetate with the classic succinate pathway. Without ferredoxin:NAD+ oxidoreductase, redox cofactors would be unbalanced; it would produce almost equal excess amounts of reduced ferredoxin and oxidized NAD. By combining growth experiments, genomics, proteomics, and enzyme assays, we point to the possibility that these bacteria solve this problem by oxidizing ferredoxin and reducing NAD with Rnf [ferredoxin-NAD+ oxidoreductase (Na+-transporting)]. Genomic and phenotypic data suggest many bacteria may use Rnf similarly. This work shows the ferredoxin:NAD+ oxidoreductase activity of Rnf is important to propionate formation in Prevotella species and other bacteria from the environment, and it provides fundamental knowledge for manipulating fermentative propionate production.

In this study, we investigated improving the performance of a layered double hydroxide (LDH) for the adsorption of As(III) and As(V) by controlling the morphology of LDH crystals. The LDH was synthesized via a simple coprecipitation method using barely soluble MgO as a precursor and succinic acid (SA) as a morphological control agent. Doping the LDH crystals with carboxylate ions (RCOO−) derived from SA caused the crystals to develop in a radial direction. This changed the pore characteristics and increased the density of active surface sites. Subsequently, SA/MgFe-LDH showed excellent affinity for As(III) and As(V) with maximum sorption densities of 2.42 and 1.60 mmol/g, respectively. By comparison, the pristine MgFe-LDH had sorption capacities of 1.56 and 1.31 mmol/g for As(III) and As(V), respectively. The LDH was effective over a wide pH range for As(III) adsorption (pH 3–8.5) and As(V) adsorption (pH 3–6.5). Using a combination of spectroscopy and sorption modeling calculations, the main sorption mechanism of As(III) and As(V) on SA/MgFe-LDH was identified as inner-sphere complexation via ligand exchange with hydroxyl group (–OH) and RCOO−. Specifically, bidentate As-Fe complexes were proposed for both As(III) and As(V) uptake, with the magnitude of formation varying with the initial As concentration. Importantly, the As-laden adsorbent had satisfactory stability in simulated real landfill leachate. These findings demonstrate that SA/MgFe-LDH exhibits considerable potential for remediation of As-contaminated water. [Display omitted] [ABSTRACT FROM AUTHOR]