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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]

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]

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]

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]

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]

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]

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]

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]

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]

Rationale: Succinic acid and lactic acid have been associated with diarrhea in weaned piglets. The level of succinic acid and lactic acid in serum, meat, and intestinal contents is important to elucidate the mechanism of diarrhea in weaned piglets. Methods: A facile method was developed for the quantification of succinic acid and lactic acid in pigs' serum, intestinal contents, and meat using ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC/MS/MS). The serum samples underwent protein precipitation with methanol. The meat and intestinal contents were freeze-dried and homogenized using a tissue grinding apparatus. Methanol-water mixture (80:20, v/v) was used for homogenizing the meat, while water was used for homogenizing the intestinal contents. An additional step of protein precipitation with acetonitrile was required for the intestinal contents. The resulting solution was diluted with water before being analyzed by UHPLC/MS/MS. Separation of succinic acid and lactic acid could be achieved within 3 min using a Kinetic XB-C18 column. Results: The coefficients of variation for peak areas of succinic acid and lactic acid were less than 5.0%. The established method demonstrated good linearity as indicated by correlation coefficients exceeding 0.996. Additionally, satisfactory recoveries ranging from 88.58% to 108.8% were obtained. The detection limits (RS/N = 3) for succinic acid and lactic acid were determined to be 0.75 ng/mL and 0.02 µg/mL, respectively. Conclusion: This method exhibited high sensitivity, simplicity in operation, and small sample weight, making it suitable for quantitative determination of succinic acid and lactic acid in pigs' serum, intestinal contents, and meat. The method developed will provide valuable technical support in studying the metabolic mechanisms of succinic acid and lactic acid in pigs. [ABSTRACT FROM AUTHOR]

Ecological nutrition aims to unravel the extensive web of nutritional links that drives animals in their interactions with their ecological environments. Nutrition plays a key role in the success of European wild rabbit (Oryctolagus cuniculus) and could be affected by the breeding status of the animals and reflected in the metabolome of this species. As nutritional needs are considerably increased during pregnancy and lactation, the main objective of this work was to determine how the breeding status (pregnant and lactating) of European wild rabbit does affects nutritional requirements and their metabolome (using targeted and untargeted metabolomics), aiming to find a useful biomarker of breeding status and for monitoring nutritional requirements. To address this gap, 60 wild European rabbits were studied. Animals were divided according to their breeding status and only pregnant (n = 18) and lactating (n = 11) rabbit does were used (n = 29 in total). The body weight and length of each animal were analyzed. The relative and absolute chemical composition of the gastric content and whole blood sample were taken, and targeted and untargeted metabolomics were analyzed. As a main result, there were no differences in biometric measurements, gastric content, and targeted metabolomics, except for live weight and nonesterified fatty acids (NEFA), as pregnant animals showed higher live weight (+12%; p = 0.0234) and lower NEFA acid levels (−46%; p = 0.0262) than lactating females. Regarding untargeted metabolomics, a good differentiation of the metabolome of the two breeding groups was confirmed, and it was proven that pregnant animals showed higher plasmatic levels of succinic anhydride (3.48 more times; p = 0.0236), succinic acid (succinate) (3.1 more times; p = 0.0068) and propionic acid (3.98 more times; p = 0.0121) than lactating animals. However, lactating animals showed higher levels of N‐[(3a,5b,7b)‐7‐hydroxy‐24‐oxo‐3‐(sulfoxide) cholan‐24‐yl]‐Glycine (cholestadien) (2.4 more times; p < 0.0420), 4‐maleyl‐acetoacetate (MAA) (3.2 more times; p < 0.0364) and irilone (2.2 more times; p = 0.0451) than pregnant animals, any of these metabolites could be used as a potential biomarker. From these results, it can be concluded that the most notable changes were observed in the metabolome of individuals, with most of the changes observed being due to energy and protein mobilisation. [ABSTRACT FROM AUTHOR]

In this study, crosslinked films of polyvinyl alcohol (PVA) were prepared using two dicarboxylic acids: saturated succinic acid (SA) and unsaturated maleic acid (MAL) as crosslinkers. The crosslinking capabilities of these acids were compared through physical, chemical, mechanical, morphological, thermal analysis, and swelling measurements to investigate their impact on the physicochemical properties of the resulting films. Attenuated total reflectance fourier transform infrared spectroscopy (FTIR) confirmed the occurrence of an esterification reaction between PVA and the dicarboxylic acids. Based on the degree of crosslinking and thermal properties, it was noted that the crosslinking achieved with maleic acid is more effective for PVA compared with succinic acid. The crosslinking degree of PVA‐MAL was determined to be 6.47 times higher than that of the PVA‐SA film. In terms of thermal stability, the decomposition temperature for crosslinked PVA‐MAL was measured at 365.57°C, whereas PVA‐SA exhibited a slightly lower decomposition temperature of 362.58°C. The findings indicate that the PVA‐MAL film displays lower crystallinity and a higher contact angle (80.60°) in contrast to PVA‐SA (76.0°) and PVA (30.4°). Atomic force microscopy analysis indicated that the PVA‐SA film exhibited more surface roughness compared with the smoother PVA‐MAL film. Also, crosslinked films displayed enhanced elasticity and resilience in comparison with neat PVA, which may be due to the difference in crosslinking density, disruption in intermolecular hydrogen bonding due to crosslinking, and incorporation of flexible crosslinkers. Highlights: PVA was crosslinked using SA and MAL.Unsaturated MAL exhibited superior crosslinking density over saturated SA.PVA‐SA film exhibited a porous surface compared to PVA‐MAL film.PVA crosslinked with unsaturated MAL showed higher thermal stability than SA.Both the films showed enhanced elasticity and resilience compared with neat PVA. [ABSTRACT FROM AUTHOR]

Objects: This study aims to explore the etiology of peri‐implantitis by comparing the metabolic profiles in peri‐implant crevicular fluid (PICF) from patients with healthy implants (PH) and those with peri‐implantitis (PI). Materials and Methods: Fifty‐six patients were enrolled in this cross‐sectional study. PICF samples were collected and analyzed using both non‐targeted and targeted metabolomics approaches. The relationship between metabolites and clinical indices including probing depth (PD), bleeding on probing (BOP), and marginal bone loss (MBL) was examined. Additionally, submucosal microbiota was collected and analyzed using 16S rRNA gene sequencing to elucidate the association between the metabolites and microbial communities. Results: Significant differences in metabolic profiles were observed between the PH and PI groups, with 179 distinct metabolites identified. In the PI group, specific amino acids and fatty acids were significantly elevated compared to the PH group. Organic acids including succinic acid, fructose‐6‐phosphate, and glucose‐6‐phosphate were markedly higher in the PI group, showing positive correlations with mean PD, BOP, and MBL. Metabolites that increased in the PI group positively correlated with the presence of Porphyromonas and Treponema and negatively with Streptococcus and Haemophilus. Conclusions: This study establishes a clear association between metabolic compositions and peri‐implant condition, highlighting enhanced metabolite activity in peri‐implantitis. These findings open avenues for further research into metabolic mechanisms of peri‐implantitis and their potential therapeutic implications. [ABSTRACT FROM AUTHOR]

In this study, we performed a quantitative analysis of 12 compounds derived from Piper sarmentosum extract (PSE) and guava leaf extract (GE). In addition, we investigated the effects of mixed extract (ME) of PSE and GE (1:1) on piglets' gut microbiome and metabolome. A total of 200 piglets (Duroc × Landrace × Large Yorkshire, 21‐day‐old) were randomly assigned into two groups with five replicates of 20 piglets/pen having the same initial body weight. Piglets were fed a basal diet supplemented with ME at 0 (T0) or 200 mg/kg (T1) for 3 weeks. The quantitation results by ultraperformance liquid chromatography linked to triple‐quadrupole tandem mass spectrometry showed that vitexin 2‐O‐rhamnoside and pellitorine were the greatest abundant among six compounds detected in the PSE. In addition, quercetin, isoquercitrin and avicularin were found to be the richest of all detected compounds in the GE. Findings on experimental animals indicated that three differential metabolites, comprising L‐alanine, sarcosine and dihydrofolic acid, in T1 compared with T0 groups, have exactly opposite levels trends in serum and faeces. Moreover, two metabolic pathways (i.e., urea cycle and glutamate metabolism) differed significantly in the serum and faeces of piglets between T0 and T1 (p < 0.05). At the same time, T1 had significantly higher relative abundances of Agathobacter and Alloprevotella than T0 at genus level (p < 0.05). Correlation analysis revealed that the genus Agathobacter correlated positively with carbamoyl phosphate (p < 0.01) and oxoglutaric acid (p < 0.05), and negatively with succinic acid (p < 0.01) and ornithine (p < 0.05). These four differential metabolites were also involved in the urea cycle and/or glutamate metabolism pathways. The results here indicated that the tested plant extract mixture represents a worthy feed additive with obvious antioxidative properties. [ABSTRACT FROM AUTHOR]

Background: The disruption of the microbial community or dysbiosis alters the functional composition, metabolic activity, and local distribution of the microbiota leading the development of acne. The aim of this study is to evaluate the effect of a lotion containing a biotechnological phytocomplex, niacinamide, and succinic acid in the bacterial diversity of subjects with truncal mild‐moderate acne and its clinical benefits due to microbiota changes. Materials and Methods: Open, clinical study in 43 subjects with truncal mild‐moderate acne treated with a lotion for 8 weeks. Bacterial diversity was analyzed by 16S rRNA gene sequencing of skin samples. Clinical effects were evaluated through IGA acne severity scale, biometric measurements, and safety. Results: After 56 days of product's use, an increase in richness alpha diversity was found (p = 0.005), with a decrease in Cutibacterium acnes relative abundance (66.43% vs. 58.11%, p = 0.009). The clinical results showed a decrease in IGA score (27.59% decrease; p = 0.001), the inflammatory lesions (52.12% decrease, p = 0.006) and erythema (18.33% decrease, p = 0.007), and desquamation index (63.83% decrease, p = 0.02). The responder analysis of the IGA score showed that 60.47% of patients improved by at least one point at day 56. The product was well tolerated along the study. Conclusion: The use of the lotion on acneic skin was effective on rebalancing the microbiota, inhibiting biofilm formation and other virulence factors, reducing erythema and desquamation, and improving acne's severity. [ABSTRACT FROM AUTHOR]

BACKGROUND: It is reported that anti‐enterovirus 71 (EV71) drugs have some side effects on human health. Notably, fungi plays a crucial role in promoting human health and anti‐virus. Grifola frondosa is a type of large medicinal and edible fungi, rich in active substances. The present study aimed to investigate the anti‐EV71 effect of G. frondosa and the potential active substances. RESULTS: In the present study, the water extract of G. frondosa was subjected to ethanol precipitation to obtain the water‐extracted supernatant of G. frondosa (GFWS) and water‐extracted precipitation of G. frondosa. Their inhibitory effects on EV71 virus were studied based on a cell model. The results showed that GFWS had stronger security and anti‐EV71 effects. In addition, the chemical constituents of GFWS were identified by ultra‐high performance liquid chromatography‐tandem mass spectrometry, which were selected for further separation and purification. Three compounds, N‐butylaniline, succinic acid and l‐tryptophan, were isolated from GFWS by NMR spectroscopy. It is noteworthy that N‐butylaniline and l‐tryptophan were isolated and identified from the G. frondosa fruiting bodies for the first time. Our study found that l‐tryptophan has anti‐EV71 virus activity, which reduced EV71‐induced apoptosis and significantly inhibited the replication process after virus adsorption. Furthermore, it could also bind to capsid protein VP1 to prevent the virus from attaching to the cells. CONCLUSION: l‐tryptophan was an inhibitor of the EV71 virus, which could be used in infant nutrition and possibly provide a new drug to treat hand, foot and mouth disease. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The present study evaluated the use of epoxidized esters of succinic acid, oleic acid, and propylene glycol as a bioplasticizer for poly(vinyl chloride) (PVC) and compared the results with the commercial phthalate plasticizer di(2‐ethylhexyl)phthalate. The chemical properties, structure, and biodegradation of the obtained bioplasticizer were analyzed. In order to analyze the influence of different PVC processing conditions on the properties of the obtained samples, the gelation process was carried out at 170, 180, 190, and 200°C at a time of 1.5–10.0 min. Mechanical properties, thermal characteristics, Fourier transform infrared spectroscopy analysis, plasticizer migration, and color change were determined for the resulting plasticized PVC samples. The performed studies allowed to confirm the obtaining of a biodegradable bioplasticizer (after 28 days, the decomposition rate in respirometry test was 72.7%). The optimal conditions for PVC processing were determined. For them the properties of the obtained material were superior. Processing PVC at 170°C for 7.5 min proved to be the most optimal conditions for the bioplasticizer synthesized in this study. Under these conditions, tensile strength of about 23 MPa and elongation at break of 200% were obtained, while plasticizer migration was very low (4.4% after 7 days and 6.8% after 28 days). [ABSTRACT FROM AUTHOR]

Plastic usage by microbes as a carbon source is a promising strategy to increase the recycling quota. 1,4‐butanediol (BDO) is a common monomer derived from polyesters and polyurethanes. In this study, Ustilago trichophora was found to be an efficient cell‐factory to valorize BDO. To investigate product formation by U. trichophora, we refined the traditional ion exclusion liquid chromatography method by examining eluent, eluent concentrations, oven temperatures, and organic modifiers to make the chromatography compatible with mass spectrometry. An LC‐UV/RI‐MS2 method is presented here to identify and quantify extracellular metabolites in the cell cultures. With this method, we successfully identified that U. trichophora secreted malic acid, succinic acid, erythritol, and mannitol into the culture medium. Adaptive laboratory evolution followed by medium optimization significantly improved U. trichophora growth on BDO and especially malic acid production. Overall, the carbon yield on the BDO substrate was approximately 33% malic acid. This study marks the first report of a Ustilaginaceae fungus capable of converting BDO into versatile chemical building blocks. Since U. trichophora is not genetically engineered, it is a promising microbial host to produce malic acid from BDO, thereby contributing to the development of the envisaged sustainable bioeconomy. [ABSTRACT FROM AUTHOR]

Antibiotics have constituted the mainstay of acne therapy despite acne being classified as an inflammatory disorder. The indiscriminate usage of antibiotics over the years has thus fueled the issue of antimicrobial resistance. Cutibacterium acnes (C. acnes) can acquire resistance due to chromosomal mutation or genetic acquisition. C. acnes can transfer resistance to other resident flora, complicating the management of skin and soft tissue infections. It can also transfer resistant strains to other body sites and to immunocompromised and elderly patients thus putting them at risk of serious infections. Recent studies have highlighted the physiologic role of C. acnes in maintaining the normal homeostasis of the skin microbiome. The role of Malassezia in causation of acne has piqued interest in recent times. The efficacy of antibiotics in acne is attributed to their para‐antibiotic, anti‐inflammatory action rather than antimicrobial action. Thus, usage of low‐dose antibiotics and alternatives to antibiotics has been advocated. Some alternative therapies showing efficacy in acne are probiotics, oral zinc, precision therapy using succinic acid, bacteriophages, and anti‐biofilm therapy like myrtacin, topical azelaic acid, and salicylic acid. Using isotretinoin in early stages of acne can reduce the incidence of scarring and alleviate the need for antibiotics. Thus, a gradual shift from antibiotics to alternative therapies in acne is the need of the hour. [ABSTRACT FROM AUTHOR]

Although a high titre of malic acid is achieved by filamentous fungi, by‐product succinic acid accumulation leads to a low yield of malic acid and is unfavourable for downstream processing. Herein, we conducted a series of metabolic rewiring strategies in a previously constructed Myceliophthora thermophila to successfully improve malate production and abolish succinic acid accumulation. First, a pyruvate carboxylase CgPYC variant with increased activity was obtained using a high‐throughput system and introduced to improve malic acid synthesis. Subsequently, shifting metabolic flux to malate synthesis from mitochondrial metabolism by deleing mitochondrial carriers of pyruvate and malate, led to a 53.7% reduction in succinic acid accumulation. The acceleration of importing cytosolic succinic acid into the mitochondria for consumption further decreased succinic acid formation by 53.3%, to 2.12 g/L. Finally, the importer of succinic acid was discovered and used to eliminate by‐product accumulation. In total, malic acid production was increased by 26.5%, relative to the start strain JG424, to 85.23 g/L and 89.02 g/L on glucose and Avicel, respectively, in the flasks. In a 5‐L fermenter, the titre of malic acid reached 182.7 g/L using glucose and 115.8 g/L using raw corncob, without any by‐product accumulation. This study would accelerate the industrial production of biobased malic acid from renewable plant biomass. [ABSTRACT FROM AUTHOR]

Polybutylene succinate (PBS) is one of the most important biobased plastics, based on the amount produced. Owing to its high melting point and resemblance to petroleum‐based plastics (i. e. PP), PBS becomes one of the emerging bioplastics with an array of applications. PBS is manufactured by polymerization of 1,4‐butanediol and succinic acid. Thus, it is of great importance to ensure the use of renewable resources to produce the PBS precursors. As the second most abundant carbohydrate monomer on Earth, D‐xylose will be a suitable candidate for this purpose. In this work, we combined protein engineering with chemical oxidation by gold catalyst to enable transformation of D‐xylose to 1,4‐butanediol and succinic acid simultaneously. In silico docking studies and semi rational design were employed to create variants of the key enzyme, branched chain α‐keto acid decarboxylase (KdcA) with higher affinity for the intermediates in the production of 1,4‐butanediol and succinic acid. Direct enzymatic biotransformation would result in a production of both monomers with 3:1 ratio, thus not readily suitable for a direct polymerization to PBS. By developing a one‐pot multi‐step chemo‐enzymatic approach with a gold catalyst to perform the first oxidation step, we could achieve a final product ratio of 1:1. Application of an engineered KdcA variant allowed us to achieve >98% yield after four hours transformation. In contrast, after 24 h transformation, >10% intermediate was still observed when the original variant was used. We anticipate this new approach could serve as an alternative route for biotechnological productions of PBS and its precursors. [ABSTRACT FROM AUTHOR]

In this work, after cationic pretreatment of cotton fabric with cetylpyridinium chloride (CPC), the compound of citric acid (CA) and succinic acid (SUA) were used as crosslinking agents to dye cotton fabrics with natural madder dye to improve the dyeing and antibacterial properties and realise the multifunctional finishing of cotton fabric. The effects of mordant dyeing, CA + SUA crosslinked dyeing, and CPC/CA + SUA crosslinked dyeing on the microstructure and properties of cotton fabrics were compared. The dyeing by the three processes occurred primarily in the amorphous zone of the fibres, and all kept the original crystalline form of the cotton. CA + SUA crosslinked dyeing and CPC/CA + SUA crosslinked dyeing increased the thermal stability of the cotton fabric. CPC/CA + SUA crosslinked dyed cotton obtained excellent dyeing results with the colour depth value (K/S) of 12.3 and rubbing fastness and washing fastness of levels 4–5, and the levelness and dye permeability were acceptable. Furthermore, the antibacterial rate against Escherichia coli and Staphylococcus aureus reached 99.99%, and the ultraviolet protection factor (UPF) reached 50+. Moreover, the wrinkle recovery angle (WRA) increased by 55% compared with raw cotton. This showed that CPC/CA + SUA crosslinked dyed cotton had excellent antibacterial, anti‐ultraviolet, and anti‐wrinkle performances. [ABSTRACT FROM AUTHOR]

This study investigates the potential of α‐HH formation from gypsum originating from activated and hydrated natural anhydrite. For this, gypsum was prepared from natural anhydrite and treated in an autoclave process under hydrothermal conditions (150 mbar and 130 °C). For comparison, fgd‐gypsum was treated accordingly. Succinic acid, maleic acid and additional α‐HH seeds were used as crystallization aids. QXRD results show the transformation of gypsum into hemihydrate after a residence time of 8 h and 4 h. SEM images distinguish the α‐HH and β‐HH modifications. For fgd‐gypsum pellets, the β‐HH modification predominates. Gypsum from natural anhydrite shows α‐HH crystals with succinic acid and without crystallization aid. When maleic acid is present, crystals appear as intermediates between α‐HH and β‐HH. To isolate the effect of the crystallization aids, α‐HH and succinic acid were used separately and simultaneously. SEM images indicate the formation of α‐HH from β‐HH. The shapes of the original β‐HH conglomerates are still visible, yet acicular crystals with smooth surfaces (α‐HH) are visible at a high magnification. Longest crystals appear when α‐HH and succinic acid are used simultaneously indicating a synergetic effect of both crystallization aids. [ABSTRACT FROM AUTHOR]

Chemicals with a four‐carbon chain (C4 chemicals), like succinic acid, maleic acid, 1,4‐butanediol, and tetrahydrofuran are extensively used as commodity chemicals and polymer precursors. Currently, these chemicals are commercially synthesized from petrochemical based feedstocks. There is a growing interest in catalytic pathways for producing these and other C4 chemicals from biomass. However, biomass is mainly composed of hexose and pentose sugars and the natural abundance of a C4 feedstock is low. This review summarizes the current development in catalytic pathways for C4 chemical synthesis from biomass derived sugars and its derivatives and suggests future direction of research. [ABSTRACT FROM AUTHOR]

Alternative sources for polymeric materials have been sought in the past few years to reduce our dependence on fossil feedstock. We report the catalytic carbonylation of acrylic acid, a platform chemical that can be bio‐sourced, as a new pathway toward the formation of a useful monomer to polyesters, namely succinic anhydride. The novel system reported herein tackles the difficult carbonylation of unsaturated carboxylic acids through the utilization of an Earth‐abundant metal catalyst, [Co2(CO)8], in presence of a bidentate ligand, 1,2‐bis(dicyclohexylphosphino)ethane (dcpe), and H2. We investigated the influence of the reaction conditions through the variations of metal, ligand, temperature, pressure, and gas composition. The carbonylative ring‐closure of acrylic acid was successfully obtained in high yield and selectivity toward the formation of succinic anhydride using mild conditions (90 °C and 16 bar of CO/H2 95 : 5). [ABSTRACT FROM AUTHOR]

Replicating the key structural feature of calcium carbonate (CaCO3) by biomolecules provides unique inspiration for synthesis of CaCO3 suitable for industry application. The biomolecule‐based morphological strategies generally contain the strong interaction between crystal and functional groups, such as carboxyl group and alcohol hydroxyl group. Here, a comparative study of low‐molecular‐weight organic acids (OAs) with structural similarity on calcite crystallization is presented. The morphological evolution of calcite from rhombohedron to ellipsoid is observed, needle‐like or dumbbell‐like in the presence of monohydroxy OAs of lactic acid, malic acid, or citric acid, suggesting carboxyl group shows more remarkable effect on the morphologies of calcite than that of Li+. The strong adsorption behavior of carboxyl group on calcite can decrease the crystallinity with increased number of carboxyl groups. In contrast, the dicarboxylic OA of tartaric acid showed stronger effects on the phase transition process from vaterite to calcite than that of succinic acid and monohydroxy OAs. These findings will aid in synthesizing CaCO3 with specific morphology and polymorph by biochemical methods and are of great significance to the industrial application of CaCO3. [ABSTRACT FROM AUTHOR]

Two novel bismuth succinate hydrates, namely, poly[[diaqua(μ3‐butane‐1,4‐dicarboxylato)hemi(μ‐butane‐1,4‐dicarboxylato)bismuth] monohydrate], {[Bi(C4H4O4)1.5(H2O)2]·H2O}n (1), and poly[[μ‐aqua‐aqua(μ3‐butane‐1,4‐dicarboxylato)(μ‐butane‐1,4‐dicarboxylato)‐μ‐oxido‐dibismuth] monohydrate], {[Bi2(C4H4O4)2O(H2O)2]·H2O}n (2), have been synthesized. Their crystal structures were determined by single‐crystal X‐ray diffraction and the compounds were characterized by IR and Raman spectroscopy, powder X‐ray diffraction and thermal analysis. The crystal structure analysis revealed that the compounds are coordination polymers, with 1 having a two‐dimensional layered structure and 2 displaying a three‐dimensional (3D) framework. Fully deprotonated succinate anions (C4H4O42−) in two different conformations (trans and gauche) are included in their composition. The Bi3+ cations are surrounded by O atoms from the carboxylate groups of succinate anions and aqua ligands. BiO9 coordination polyhedra in 1 are connected in pairs by edges. These pairs are bound together by bridging succinate ligands to form layers. Bismuth coordination polyhedra of two different types (BiO9 and BiO7) in 2 are connected by edges to form infinite ribbons. Ribbons of polyhedra with bridging succinate ligands form a 3D polymeric structure. [ABSTRACT FROM AUTHOR]

Bladder cancer (BCa) is one of the most common malignancies worldwide. Although multiple efforts have been made, the 5‐year survival rate of patients with BCa remains unchanged in recent years. Overexpression of the epidermal growth factor receptor (EGFR) is found in ≈74% of BCa tissue specimens; however, current EGFR‐based targeted therapies show little benefit for BCa patients, as the EGFR downstream pathways appear to be circumvented by other receptor tyrosine kinases (RTKs). In this study, two natural products are identified, namely triptolide (TPL) and hesperidin (HSP), that target and inhibit the EGFR and its downstream PI3K/AKT pathway in BCa. To synergistically combine triptolide and hesperidin, a succinic acid linker was employed to conjugate them and formed an amphiphilic TPL‐HSP EGFR‐targeting prodrug (THE), which further self‐assembled to generate nanoparticles (THE NPs). These NPs allowed the EGFR‐targeted delivery of the triptolide and hesperidin, and simultaneous inhibition of the EGFR and PI3K/AKT both in vitro and in vivo. This study provides a promising EGFR‐targeted delivery approach with the dual inhibition of the EGFR and PI3K/AKT, while also exhibiting a high drug loading and low toxicity. Our formulation may be a suitable option to deliver natural products for BCa treatment by EGFR‐targeted therapy. [ABSTRACT FROM AUTHOR]

Edible films can be used for food packaging to extend the shelf life of foods and protect them from exposure to moisture, microorganisms, pathogens, and bacteria. In the present study, the effect of plasticization and cross‐linking, which are modification approaches for upgrading the properties of starch, are investigated. Glycerol and sorbitol are used as plasticizing agents, and succinic acid is used as a cross‐linking agent. The results demonstrate that the addition of glycerol and sorbitol to the film‐forming solutions reduces brittleness and increases peeling ability and flexibility upon drying. Furthermore, the film matrix supports improvements in water vapor permeability (WVP), swelling index (SI), and mechanical properties. The glycerol‐based finger millet starch (FMS) films exhibits better thermal stability than the sorbitol‐based FMS film. The microscopic images of the films show that the use of glycerol in the film improves compactness and homogeneity compared to sorbitol‐based FMS films. [ABSTRACT FROM AUTHOR]

Common wisdom holds that ATP hydrolysis is spontaneous because of the weakness of its phosphoanhydride bonds, electrostatic repulsion within the polyanionic ATP4− molecule, and resonance stabilization of the inorganic phosphate and ADP products. By examining the pH‐dependence of the hydrolysis Gibbs free energy, we show that in fact, above pH 7, ATP hydrolysis is spontaneous due mainly to the low concentration of the H+ that is released as product. Hence, ATP is essentially just an electrophilic target whose attack by H2O causes the acidity of the water nucleophile to increase dramatically; the spontaneity of the resulting acid ionization supplies much of the released Gibbs free energy. We also find that fermentation lowers pH not due to its organic acid products (e.g., lactic, acetic, formic, or succinic acids), but again, due to the H+ product of ATP hydrolysis. [ABSTRACT FROM AUTHOR]

Polybutylene succinate (PBS) and other succinic (co)polyesters are biodegradable polymers with favorable mechanical and thermal properties that find use in many applications. Due to environmental concerns, polymers based on succinic acid (SA) have been gaining attention, as SA can be produced through biotechnological processes. Thus, this review aims to highlight the synthesis and characteristics of PBS and other succinic copolyesters, with emphasis in the works employing metallic catalysts and enzymes. In addition, the modification of the macromolecular structure by copolymerization or postpolymerization is also discussed. Currently, metallic catalysts are normally used in the synthesis of these materials, under conditions of high temperatures, which can favor the occurrence of thermal degradation, increasing the dispersion of chain length distributions. Moreover, the incrustation of metallic catalysts in polymeric materials makes their application in biomedical products difficult, due to toxicity requirements. In this context, enzymatic catalysis is gaining ground, offering milder synthesis temperatures, high selectivity, and uniformity of synthesized products. This biotechnological route can substitute oligomerization processes with metallic catalysis in future industrial processes, producing materials free from metallic contamination. In addition to production by catalytic routes, trends for future applications of succinic (co)polyesters are presented, with emphasis on the value‐added materials sectors. [ABSTRACT FROM AUTHOR]

Mixed plastic waste is challenging for any recycling process. Here, an enzymatic recycling process is compared with a biotechnological upcycling process for valorizing mixed plastic waste constituted by PLA, PET, and PP. Both process routes are modeled in Aspen Plus, analyzed for bottlenecks, cost drivers, and sensitivity regarding enzymatic and microbial performance. While enzymatic recycling is only viable for uniform plastic feedstock, biotechnological upcycling operating at optimized process conditions reveals the potential to produce carbon‐neutral succinic acid from mixed plastic waste. [ABSTRACT FROM AUTHOR]

To investigate the spatial changes in origins and impact of long‐range transported air masses on organic aerosols (OA) loading and composition over Northeast Asia, fine aerosols (PM2.5) were collected at three sites: Tianjin (TJ), North China and in Padori (PD), and Daejeon (DJ), South Korea, during winter 2019. We studied molecular distributions and compound‐specific stable carbon isotopic composition (δ13C) of dicarboxylic acids, oxocarboxylic acids and α‐dicarbonyls, and carbonaceous and inorganic ionic components in PM2.5. Concentrations of organic carbon was drastically enhanced in haze period compared to that in clean period, but elemental carbon was almost comparable between the two periods. Concentrations of total diacids, oxoacids, and α‐dicarbonyls were higher at TJ followed by DJ and PD during haze period and at DJ followed by TJ and PD during clean period. On average, oxalic acid (C2) was the most abundant among measured species at all three sites, followed by methyl glyoxal (MeGly) and glyoxylic acid (ωC2) at TJ and DJ, and succinic acid (C4) and ωC2 were almost equal and second most abundant followed by MeGly at PD. Based on the mass ratios and linear relations of selected species together with δ13C of diacids and related compounds, we found that contributions of OA from biomass burning/biogenic emissions and their aging were higher at TJ and PD, whereas at DJ, emissions from anthropogenic sources and in situ secondary formation were also important. Furthermore, this study implies that long‐range atmospheric transport of aerosols from source regions to downwind regions are substantial over Northeast Asia. Plain Language Summary: Fine atmospheric aerosols (PM2.5) collected at three sites: Tianjin (TJ), North China and in Padori (PD), and Daejeon (DJ), South Korea, during winter 2019 were studied for molecular distributions and compound‐specific carbon isotopic composition (δ13C) of dicarboxylic acids (diacids), oxocarboxylic acids (oxoacids), and α‐dicarbonyls as well as the carbonaceous and inorganic ionic components. The results obtained from this study suggested that the contributions of organic aerosols from biomass burning/biogenic emissions and their photochemical secondary formation and transformations (aging) are higher at TJ and PD, whereas at DJ, the emissions from anthropogenic sources and in situ secondary formation are also important. This study also implies that contributions of long‐range transported aerosols from source regions to downwind regions such as PD and DJ are substantial over Northeast Asia. Key Points: Diacids, oxoacids, and α‐diacarbonyls were characterized in fine aerosols (PM2.5) from Tianjin, China, and Padori and Daejeon, South KoreaBiomass burning/biogenic emissions and their aging are higher at Tianjin and Padori and anthropogenic emissions are also important at DaejeonLong‐range atmospheric transport of the air masses from source regions to downwind regions are substantial over the Notheast Asian region [ABSTRACT FROM AUTHOR]

The current approach to gluconic acid production is acetification at 30°C, a temperature that can be difficult to maintain in tropical countries. This study investigated the production of gluconic acid during acetification by Acetobacter aceti WK at high temperatures. An acid‐tolerant and thermotolerant species, A. aceti WK, was used for acetification at three different temperatures, namely, 30°C (normal temperature), 37°C, and 40°C (high temperature). Acetification was performed in a 100 L bioreactor with 0.15% CaCl2 for protection of the cells against high temperatures. The production of the organic acids, that is, acetic acid, gluconic acid, 2‐keto gluconic acid, glucuronic acid, citric acid, succinic acid, lactic acid, and formic acid, was analyzed. Under acetification in the target total concentration of 80 g/L, the highest acetic acid content (39.3 g/L) was obtained at 37°C with an acetification rate of 0.3013 g/L/h, while the acetic acid content and acetification rate achieved at 30°C were 31 g/L and 0.3089 g/L/h, respectively. Additionally, gluconic acid presented at the highest concentration of 2.17 g/L. The rate of production of gluconic acid was 0.0169 g/L/h at 37°C. This acetification process at 37°C will be valuable as an alternative source for gluconic acid production for commercial applications. [ABSTRACT FROM AUTHOR]

This study involves the isolation of succinic acid (SA)‐producing microorganisms from different samples, including the rumen, sludge, soil, and wastewater. For primary screening, 29 isolates exhibited a zone of clearance around the colony, indicating acid production. For secondary screening using thin‐layer chromatography, only two isolates symbolized SA production according to their Rf values. These two isolates were further identified as Bacillus velezensis and Enterococcus gallinarum by phylogenetic analysis using the neighbor‐joining method. The high SA concentrations of 50.2 and 66.9 g/L were produced by B. velezensis and E. gallinarum with an SA yield of 0.836 and 1.12 g/g glucose, respectively. The high SA concentration from these newly isolated strains was achieved with a low formation of unwanted acids compared with those from Actinobacillus succinogenes ATCC 55618. Moreover, E. gallinarum was cultured in palm oil mill wastewater (POMW) and molasses, which were cheap substrates. The high SA production of 73.9 g/L with low other acids (the ratio of SA to total acids = 0.917) was achieved using POMW and molasses (80:20) as substrates. [ABSTRACT FROM AUTHOR]

This study investigated the interactions of four bacteria strains isolated from Yamahai‐shubo, the source of yeast used to produce a Japanese traditional rice wine, Yamahai‐shikomi sake. The bacterial strains were nitrate‐reducing Pseudomonas sp. 61‐02, Leuconostoc mesenteroides LM‐1, Lactiplantibacillus plantarum LP‐2, and Latilactobacillus sakei LS‐4. We examined fermentation factors for Yamahai‐shubo and Yamahai‐shikomi sake samples to compare the suitability of their bacterial combination (16 variations). As a result of principal component analysis, we found that two major groups were formed; one containing strain LP‐2 and the other containing strain LS‐4, and that strains LP‐2 and LS‐4 were important in the Yamahai‐shikomi sake in the presence of strains 61‐02 and LM‐1. Then, we investigated the effects of strains LP‐2 and LS‐4 on the concentration of organic acids (pyruvic acid, citric acid, succinic acid, malic acid, and lactic acid) in Yamahai‐shikomi sake. Only in lactic acid, a tendency to decrease with a smaller proportion of LS‐4 strains in Yamahai‐shubo was observed. Subsequently, their effect on the concentration of diacetyl, crucial for aroma, was investigated between the LP‐2 and LS‐4 strains. The sample prepared in the absence of strain LS‐4 exhibited the lowest concentration of diacetyl. This result was supported by the statistical analysis for the sensory scores performed for aroma of each Yamahai‐shikomi sake sample. In conclusion, strain LP‐2 plays a more significant role in improving Yamahai‐shikomi sake quality with strains LM‐1 and 61‐02 rather than strain LS‐4 in Yamahai‐shubo preparation and Yamahai‐shikomi sake brewing. [ABSTRACT FROM AUTHOR]

Succinic semialdehyde dehydrogenase (SSADH) catalyses the conversion of succinic semialdehyde into succinic acid and two electrons are transferred to NAD(P)+ to yield NAD(P)H. Our previous work has already reported the catalytic role of Cys289 of two‐cysteine SSADH from Acinetobacter baumannii (AbSSADH). However, the mechanistic role of the neighbouring conserved Cys291 and Glu255 remains unexplored. In this study, the functional roles of Cys291 and Glu255 in AbSSADH catalysis have been characterized. Results demonstrated that the E255A activity was almost completely lost, ~ 7000‐fold lower than the wild‐type (WT), indicating that Glu255 is very crucial and directly involved in AbSSADH catalysis. However, the C291A and C291S variants activity and catalytic turnover (kcat) decreased ~ 2‐fold and 9‐fold respectively. To further characterize the functional roles of Cys291, we employed two pH‐dependent methods; pre‐steady‐state burst amplitude and NADP–enzyme adduct formation. The results showed that the pKa values of catalytic Cys289 measured for the WT and C291A reactions were 7.8 and 8.7–8.8, respectively, suggesting that Cys291 can lower the pKa of Cys289 and consequently trigger the deprotonation of a Cys289 thiol. In addition, the Cys291 also plays a role in disulfide/sulfhydryl redox regulation for AbSSADH activity. Hence, we demonstrated for the first time the dual functions of Cys291 in enhancing the nucleophilicity of the catalytic Cys289 and regulating a disulfide/sulfhydryl redox switch for AbSSADH catalysis. The mechanistic insights into the nucleophilicity enhancement of the catalytic cysteine of AbSSADH might be applicable to understanding how the microenvironment increases cysteine reactivity in other enzymes in the aldehyde dehydrogenase superfamily. [ABSTRACT FROM AUTHOR]

This work investigated the curing and degradation behavior of compounds made with 1:1 of bisphenol A diglycidyl ether and epoxidized soybean oil, cured with itaconic acid (ITA) and succinic acid (SUC), coded as EP/ITA and EP/SUC. Complex peaks observed in differential scanning calorimetry are mostly due to the catalyzed curing and homopolymerization. Fourier transform infrared spectroscopy spectra suggest that the curing follows the SN2 reaction mechanism for both compounds. Lower activation energies of curing were verified for EP/ITA compared to the EP/SUC, mainly due to their greater reactivity with the epoxy matrix at temperatures below the acids structures and melting points. Regarding thermal degradation, four steps were verified: acid degradation, degradation of the non‐cross‐linked material, degradation of cross‐linked material, and carbon decomposition. EP/SUC with a molar ratio equal to 0.4 presented the lowest activation energy for degradation. The degradation's solid‐state mechanisms analysis indicated that in EP/ITA and EP/SUC compounds the processes are controlled by nucleation and subsequent growth. [ABSTRACT FROM AUTHOR]

A simplified and scalable one‐pot process for the anaerobic production of succinic acid using a metabolically engineered Corynebacterium glutamicum strain is demonstrated. With targeted bioprocess optimization, succinic acid titer of 78 g L−1 and yield of 1.41 molSAmolGLC−1 were achieved. Succinic acid was recovered from the neutral fermentation broth by electrochemically induced crystallization and applied for polybutylene bio‐succinate synthesis using a biocompatible zinc catalyst. Except for a slight color change, the final biopolymer was comparable to the polymer from commercial precursors. [ABSTRACT FROM AUTHOR]

Styrene has been widely used as a reactive diluent for a variety of commercial unsaturated polyester resins (UPRs), but suffered from high volatility. In this work, we developed a bio‐based reactive diluent, 4‐vinylguaiacol glycidyl ether (DE4VG), via an epoxidation of 4‐vinylguaiacol (4VG). Excellent miscibility and high reactivity of DE4VG were demonstrated by a series of copolymerization tests with an unsaturated polyester prepolymer (named PMSD) synthesized from maleic anhydride, 1,3‐dihydroxypropane and succinic acid. While, significant advantages in terms of viscosity and volatility were confirmed. Additionally, DE4VG provides both vinyl and epoxide groups and the epoxide groups were cured using 4,4‐diamino diphenylmethane (DDM) to participate the network formation of the cured PMSD/DE4VG/TBPB/DDM resin, resulting in high glass transition temperature (Tg, 195°C), residual carbon (45.5%), tensile strength (41.75 MPa), and the elongation at break (4.5%), which were all significantly surpassed the cured PMSD/St/TBPB, PMSD/St/TBPB/DDM, PMSD/DE4VG/TBPB resin. This work provided a successful demonstration to replace styrene with a bio‐based reactive diluent in UPR preparation, not only overcame the high volatility of styrene, but also enhanced material performances of the cured resin. [ABSTRACT FROM AUTHOR]

A novel functional supramolecular gel (SA‐MEA) has been produced through the mixing of succinic acid and monoethanolamine directly in DMF medium under ambient conditions. The semi‐solid and viscoelastic nature of mechanically stable SA‐MEA gel has been established through the rheological analysis. The major chemical components of the gel are confirmed by EDX elemental mapping, while FESEM microstructural analysis investigates the morphological patterns of the gel. The gel gives rise to crystalline materials at room temperature and in the absence of external stimuli. Single‐crystal diffraction study of the in‐situ generated crystals shows the existence of different supramolecular synthons involving the hydrogen‐bonding interactions (N−H⋅⋅⋅O and O−H⋅⋅⋅O) leading to the formation of graph set motifs. These structural building blocks provide the stability to hold the overall molecular framework of SA‐MEA gel. Moreover, the contribution of O⋅⋅⋅H/H⋅⋅⋅O contacts plays a crucial role in this gel formation, which is established from the Hirshfeld surfaces along with linked 2D fingerprint patterns of the plot for both molecular components. Additionally, the SA‐MEA gel's supramolecular structure exhibits electrical conductivity, which was exploited to construct an electronic device with a metal‐semiconductor (MS) junction. Analyses of the gel's electrical properties were done in‐depth. Inclusive, this work demonstrates that the SA‐MEA gel may be used to create a semi‐conductive microelectronic device, such as a Schottky barrier diode. [ABSTRACT FROM AUTHOR]

The design of molecularly selective membranes is of paramount importance in the electrochemical separation of organic acids from complex fermentation streams, due to the presence of multicomponent species. However, current membrane-integrated electrochemical technologies have relied on ionexchange membranes that lack intrinsic ion-selectivity, thus preventing their application for value-added recovery of organic acids from competing ions. Here, this study demonstrates a layer-by-layer polyelectrolyte functionalization approach for controlling ion-selectivity, to achieve the multicomponent separation of organic acids in a redox-flow electrodialysis platform. This study carries out a detailed investigation of the surface morphology and physicochemical properties of functionalized membranes, underlying that the selectivity of organic acids can be precisely tuned through the control of the hydrophilicity, electrostatic repulsion, and steric hindrance. Tailoring of membrane physiochemical properties enables up to complete retention of succinate, while enhancing the total flux. This organic acid retention is extended to the control over mono- and multivalent organic acids. Integration offunctionalized membrane with the redox-flow system allows selective succinic acid recovery with 99.7% purity from a synthetic fermentation mixture, high energy efficiency, and membrane stability. Modulation of ion-selectivity through membrane functionalization coupled with electrochemical architecture design enables a sustainable pathway for multicomponent separations in biomanufacturing. x2su@illinois.edu [ABSTRACT FROM AUTHOR]

The structure of model compounds for the amphiphilic copolymer poly(diisobutylene‐alt‐maleic acid), DIBMA, is investigated with (gas phase) B3LYP/6‐31G** and PM7 calculations. It is found that in the monoprotonated state of the repeating unit strong (about 70 kJ mol−1) ionic hydrogen bonds are formed within the hydrogen succinate rings, which impart partial structural rigidity on the backbone of the copolymer. Based on literature pKa values of the first and second deprotonation step of the succinic acid units, it is argued that the ionic hydrogen bonds are likely to be present in aqueous solution as well. The main chain conformation depends strongly on the stereochemical configuration of the carbon atoms in the hydrogen succinate rings. The possible consequences of the hydrogen bonding for the mechanism of membrane solubilization by maleic acid‐based amphiphilic copolymers are discussed. [ABSTRACT FROM AUTHOR]

Eight cocrystals containing an isoniazid derivative derivatized with diacetone alcohol [N′‐[(2E)‐4‐hydroxy‐4‐methylpentan‐2‐ylidene]pyridine‐4‐carbohydrazide, iz4h4m2p] were synthesized and characterized. All coformers used in this work feature at least one carboxylic acid functional group. These coformers include: succinic acid, 3,5‐dinitrobenzoic acid, 4‐nitrobenzoic acid, 2‐chloro‐4‐nitrobenzoic acid, 2,5‐dihydroxybenzoic acid, 3‐hydroxybenzoic acid, 4‐hydroxybenzoic acid and cinammic acid. Crystal structures were obtained using single crystal X‐ray diffraction, which shows that cocrystals containing iz4h4m2p feature a similar chain hydrogen bond between molecules of iz4h4m2p in addition to the expected carboxylic acid...pyridine hydrogen‐bond interaction. Differences between the structures arise when additional hydroxyl group(s) are present, such as the case featuring the hydroxybenzoic acids. These structures are compared to their isoniazid counterparts presented previously in the literature. All cocrystals were also characterized with differential scanning calorimetry and Fourier transform infrared spectroscopy. [ABSTRACT FROM AUTHOR]

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The valorization of alkenoic acids possibly deriving from biomass (fumaric and citraconic acids) was carried out through conversion in important building blocks, such as γ‐keto acids and succinic acid derivatives. The functionalization was carried out by addition onto the C=C double bond of radicals generated under photocatalyzed conditions from suitable hydrogen donors (mainly aldehydes) and by adopting a decatungstate salt as the photocatalyst. Syntheses were performed under batch (in a glass vessel) and flow (by using 3D‐printed reactors) conditions. The design of the latter reactors allowed for an improved yield and productivity. [ABSTRACT FROM AUTHOR]

Treatment or processing of starch with organic acids (citric, stearic, succinic, and malic acids) can be used to obtain starch properties like low retrogradation, desirable viscosity, shear resistance, and high resistant starch. Esterification, cross linking, and hydrolysis of starch may occur after modification with organic acids (citric, succinic acid, malic acid) whereas a complex between starch and stearic acid may be formed on use of stearic acid. The conditions of reactions namely duration, starch acid concentration ratio, and temperature may influence physicochemical and structural properties of starch. Citric acid, succinic acid, stearic acid, and malic acid are regarded as "GRAS" and thus the starch citrate, starch succinate, starch stearate, and starch maleate are widely used in manufacturing of starch films, blends, nanoparticles, fat replacer, viscosity enhancer, and many other products. This review paper discusses the reaction conditions of organic acid modification of starches along with their influence on physicochemical and structural characteristics. [ABSTRACT FROM AUTHOR]