Search Results (6)

The basidiomycete Crucibulum laeve strain LE-BIN1700 (Agaricales, Nidulariaceae) is able to grow on agar media supplemented with individual components of lignocellulose such as lignin, cellulose, xylan, xyloglucan, arabinoxylan, starch and pectin, and also to effectively destroy and digest birch, alder and pine sawdust. C. laeve produces a unique repertoire of proteins for the saccharification of the plant biomass, including predominantly oxidative enzymes such as laccases (family AA1_1 CAZymes), GMC oxidoreductases (family AA3_2 CAZymes), FAD-oligosaccharide oxidase (family AA7 CAZymes) and lytic polysaccharide monooxygenases (family LPMO X325), as well as accompanying acetyl esterases and loosenine-like expansins. Metabolomic analysis revealed that, specifically, monosaccharides and carboxylic acids were the key low molecular metabolites in the C. laeve culture liquids in the experimental conditions. The proportion of monosaccharides and polyols in the total pool of identified compounds increased on the sawdust-containing media. Multiple copies of the family AA1_1, AA3_2, AA7 and LPMOs CAZyme genes, as well as eight genes encoding proteins of the YvrE superfamily (COG3386), which includes sugar lactone lactonases, were predicted in the C. laeve genome. According to metabolic pathway analysis, the litter saprotroph C. laeve can catabolize D-gluconic and D-galacturonic acids, and possibly other aldonic acids, which seems to confer certain ecological advantages. Full article

Lactobionic acid (Lba), an oligosaccharide aldonic acid, has demonstrated various health-promoting benefits and applications in diverse areas. Lba has been recognized for its multifunctional properties, such as metal ion chelation and calcium sequestration. This study aimed to evaluate the effects of supplementing the diet of early-laying hens with Lba (EXP group) on their performance and the physical–chemical properties, and nutritional quality of eggs. The 12-week study involved 700 Sonja breed hens per group, with the EXP group’s diet enriched with 2% of biotechnologically produced Lba, while the control group (CON) received no Lba supplementation. Lba supplementation influenced both the hen’s performance and egg quality, particularly in terms of egg production and fatty acid accumulation. Performance in the EXP group was significantly improved (p < 0.05), showing a 4.6–8.9% increase compared to the CON group at all experiment stages. Lba also promoted an increase in monounsaturated fatty acid (MUFA) content, particularly palmitoleic and vaccenic acids. Overall, Lba supplementation enhanced both the productivity of laying hens and the nutritional value of eggs during the early laying period. Full article

Stonikacidin A (1), the first representative of a new class of 4-bromopyrrole alkaloids containing an aldonic acid core, was isolated from the marine sponge Lissodendoryx papillosa. The compound is named in honor of Prof. Valentin A. Stonik, who is one of the outstanding investigators in the field of marine natural chemistry. The structure of 1 was determined using NMR, MS analysis, and chemical correlations. The L-idonic acid core was established by the comparison of GC, NMR, MS, and optical rotation data of methyl-pentaacetyl-aldonates obtained from the hydrolysis products of 1 and standard hexoses. The L-form of the idonic acid residue in 1 was confirmed by GC analysis of pentaacetate of (S)-2-butyl ester of the hydrolysis product from 1 and compared with corresponding derivatives of L- and D-idonic acids. The biosynthetic pathway for stonikacidin A (1) was proposed. The alkaloid 1 inhibited the growth of Staphylococcus aureus and Escherichia coli test strains, as well as affected the formation of S. aureus and E. coli biofilms. Compound 1 inhibited the activity of sortase A. Molecular docking data showed that stonikacidin A (1) can bind with sortase A due to the interactions between its bromine atoms and some amino acid residues of the enzyme. Full article

Studies of the processes of the hydrolytic oxidation of disaccharides are the first step towards the development of technologies for the direct conversion of plant polysaccharides, primarily cellulose, into aldonic and aldaric acids, which are widely used in chemical synthesis and various industries. In this study, heterogeneous catalysts based on a porous matrix of hypercrosslinked polystyrene (HPS) and noble metals (Pt, Au, Ru, and Pd) were proposed for the hydrolytic oxidation of cellobiose to gluconic and glucaric acids. The catalysts were characterized using low-temperature nitrogen adsorption, hydrogen chemisorption, electron microscopy, and other methods. In particular, it was shown that the Pt-containing catalyst contained, on average, six times more active centers on the surface, which made it more promising for use in this reaction. At a temperature of 145 °C, an O₂ pressure of 5 bars, and a substrate/catalyst weight ratio of 4/1, the yields of gluconic and glucaric acids reached 21.6 and 63.4%, respectively. Based on the data obtained, the mathematical model of the cellobiose hydrolytic oxidation kinetics in the presence of 3% Pt/HPS MN270 was developed, and the parameter estimation was carried out. The formal description of the kinetics of cellobiose hydrolytic oxidation was obtained. Full article

The effects of soilless substrate-based versus soil cultivation on overall fruit quality and yield in tomato (Solanum lycopersicum) were studied using the tomato cv. Zhonghua Lvbao. Experiments for tomato soilless cultivation were carried out under greenhouse conditions. Plant growth, fruit quality and yield, and physiologic traits were observed. RNA-seq and RT-PCR, as well as metabolomic analyses were performed to examine the expressed genes and metabolites under soilless substrate cultivation. The results showed that the plant height, stem diameter, and chlorophyll contents of tomato under substrate-based cultivation were increased by 37.3%, 19.8%, and 15.3%, respectively, compared with soil cultivation system. Leaf photosynthetic and transpiration rates, stomatal conductance, and root vitality of tomato, under substrate-based cultivation, increased by 29.0%, 21.2%, 43.9%, and 84.5%, respectively, compared with soil cultivation. The yield reached 7177.5 kg/667 m², and the relative yield increased by 10.1%, compared with soil cultivation. The contents of total soluble sugar, soluble solids, and vitamin C increased by 35.7%, 19.7%, and 18.2%, respectively, higher than those of soil cultivation in tomato fruits, while nitrate content and titratable acid decreased by 29.4% and 11.8%, respectively. Therefore, substrate-based-cultivation can increase production and improve tomato fruit quality and taste. We examined the expressed genes and metabolites to explore the molecular mechanism of plant growth and overall fruit quality improvement in substrate-based cultivation. A total of 476 differentially expressed genes were identified by transcriptomes profiling, of which 321 and 155 were significantly up- and down-regulated, respectively. The results of metabolomics analysis showed that 441 metabolites were detected, where 24 and 36 metabolites were up- and down-regulated, respectively. By combining analyses of transcriptomic and metabolic groups, genes and metabolites related to the fruit quality were mainly concentrated in the vitamin B6/ascorbic acid/aldonic acidmetabolism, and glycerophospholipid metabolic pathways. Therefore, substrate-based cultivation can elevate vitamin and soluble sugar contents and the expression of fruit flavor related genes, which lays an initial background for exploring the mechanism of substrate-based cultivation, in order to improve the quality of tomato in the future. Full article

Carbonaceous meteorites provide the best glimpse into the solar system’s earliest physical and chemical processes. These ancient objects, ~4.56 billion years old, contain evidence of phenomena ranging from solar system formation to the synthesis of organic compounds by aqueous and (likely) low-temperature photolytic reactions. Collectively, chemical reactions resulted in an insoluble kerogen-like carbon phase and a complex mixture of discrete soluble compounds including amino acids, nucleobases, and monosaccharide (or “sugar”) derivatives. This review presents the documented search for sugars and their derivatives in carbonaceous meteorites. We examine early papers, published in the early 1960s, and note the analytical methods used for meteorite analysis as well as conclusions on the results. We then present the recent finding of sugar derivatives including sugar alcohols and several sugar acids: The latter compounds were found to possess unusual “d” enantiomeric (mirror-image) excesses. After discussions on the possible roles of interstellar grain chemistry and meteorite parent body aqueous activity in the synthesis of sugar derivatives, we present a scenario that suggests that most of Earth’s extraterrestrial sugar alcohols (e.g., glycerol) were synthesized by interstellar irradiation and/or cold grain chemistry and that the early solar disk was the location of the initial enantiomeric excesses in meteoritic sugar derivatives. Full article