Enhancement of soluble protein, polypeptide production and functional properties of heat-denatured soybean meal by fermentation of Monascus purpureus 04093

Transcriptomic and Metabolomic Analyses of Soybean Protein Isolate on Monascus Pigments and Monacolin K Production

Monascus pigments (MPs) and monacolin K (MK) are important secondary metabolites produced by Monascus spp. This study aimed to investigate the effect of soybean protein isolate (SPI) on the biosynthesis of MPs and MK based on the analysis of physiological indicators, transcriptomes, and metabolomes. The results indicated that the growth, yellow MPs, and MK production of Monascus pilosus MS-1 were significantly enhanced by SPI, which were 8.20, 8.01, and 1.91 times higher than that of the control, respectively. The utilization of a nitrogen source, protease activity, the production and utilization of soluble protein, polypeptides, and free amino acids were also promoted by SPI. The transcriptomic analysis revealed that the genes mokA, mokB, mokC, mokD, mokE, mokI, and mokH which are involved in MK biosynthesis were significantly up-regulated by SPI. Moreover, the glycolysis/gluconeogenesis, pyruvate metabolism, fatty acid degradation, tricarboxylic acid (TCA) cycle, and amino acid metabolism were effectively up-regulated by SPI. The metabolomic analysis indicated that metabolisms of amino acid, lipid, pyruvate, TCA cycle, glycolysis/gluconeogenesis, starch and sucrose, and pentose phosphate pathway were significantly disturbed by SPI. Thus, MPs and MK production promoted by SPI were mainly attributed to the increased biomass, up-regulated gene expression level, and more precursors and energies.

Unveiling the potential of red koji polysaccharides: biosynthesis, extraction, and multifaceted biological activities

Red koji polysaccharides, derived from the fermentation of Monascus, have been recognized for their health-enhancing properties. This article reviews their structural characteristics, biosynthesis pathways, and biological activities. It emphasizes the need for sustainable practices in fermentation and the optimization of extraction methods for scalable production. The significance of exploring the molecular mechanisms involved in their biosynthesis is also highlighted to enhance yield and efficiency. Research indicates that red koji polysaccharides possess diverse biological functions, beneficial for pharmaceutical applications due to their health benefits and minimal toxicity. The review points out the necessity for more detailed studies on key enzymes and genes in biosynthesis to improve production methods. It also identifies the current challenges in production scalability and extraction efficiency. Furthermore, while these polysaccharides show potential in pharmaceuticals, their clinical efficacy and mechanism of action in human subjects require further investigation. The review briefly explores potential structural modifications to improve their biological activities. The review concludes that red koji polysaccharides hold significant untapped potential, particularly in drug formulation. Future research should focus on overcoming current production and application challenges, including conducting clinical trials to validate their efficacy and exploring structural modifications for enhanced therapeutic benefits. This comprehensive understanding of red koji polysaccharides paves the way for their expanded application in the pharmaceutical industry. © 2024 Society of Chemical Industry.

Incorporation of Blue Honeysuckle Juice into Fermented Goat Milk: Physicochemical, Sensory and Antioxidant Characteristics and In Vitro Gastrointestinal Digestion

The addition of fruit juice may improve the physicochemical and functional characteristics of dairy products. The study evaluated the effect of 1−6% (v/v) blue honeysuckle juice (BHJ) on the physicochemical, sensory and antioxidant characteristics of fermented goat milk (FGM) during 21 days of refrigerated storage and in vitro gastrointestinal digestion. The incorporation of BHJ significantly increased (p < 0.05) the water-holding capacity, viscosity, redness (a*) value, total phenolic content (TPC) and ferric ion-reducing antioxidant power during storage. Additionally, BHJ affected the microstructure and sensory score of the samples. FGM treated with 4% (v/v) BHJ exhibited the highest overall acceptability. The supplementation of BHJ diminished the goaty flavor and promoted in vitro protein digestion. Furthermore, the TPC was enhanced in addition to the antioxidant activity of FGM containing BHJ throughout the in vitro digestion. Therefore, FGM supplemented with BHJ serves as a novel and attractive goat dairy product.

Effect of Fungal Fermentation on Enhancement of Nutritional Value and Antioxidant Activity of Defatted Oilseed Meals

Agro-industrial residues contain high nutritive value. Nowadays, various advanced researches have been done for the production of various value-added products, using these wastes as substrates in the fermentation media. Flaxseed, mustard, and rice bran meal, residues of oil industry, were used as substrates for fermentation. Submerged fermentation with soil-isolated fungal species of the genus Aspergillus sp. was done for oil production by using these substrates in the fermentation media. Effect of fermentation by the oleaginous species of Aspergillus on the nutritive value and functional properties of flaxseed, mustard, and rice bran meal has been discussed for the first time in the present study. After fermentation, the seed meals showed substantial increase in the protein and ash content. The fungal strains utilized the carbohydrate present in the seed meals for the production of highly nutritional metabolites, which decrease the sugar contents of the meals. The fungi also showed extracellular amylase and cellulase activities which helped to hydrolyze the carbohydrates present in these meals, to utilize them for their metabolism. The enhancement was also observed in terms of antioxidant activity of the meals. Increase in the total phenolic and flavonoid contents was observed after fermentation along with radical scavenging activity of 1,1-diphenyl-2-picrylhydrazyl and 2,2-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid reagents and ferric reduction potential. These effects of fermentation modify these cheap waste materials into nutrient dense substrates, which could be further used in the formulation of value-added products.

Changes in Carbon Partitioning and Pattern of Antioxidant Enzyme Activity Induced by Arginine Treatment in the Green Microalga Dunaliella salina Under Long-Term Salinity

In this work, the effects of arginine (Arg) on biochemical responses and antioxidant enzyme activity in the green microalga Dunaliella salina grown at different salt concentrations were investigated. Suspensions adapted with the concentrations of 1, 2, and 3 M NaCl were treated at the exponential growth phase with a concentration of 5 mM Arg. Salt stress was associated with a large decrease in the number of cells and non-reducing sugar levels but accumulated higher amounts of chlorophyll, β-carotene, reducing sugar, starch, total protein, free amino acid, and glycerol. Increased levels of protein carbonylation, lipid peroxidation, proteolysis, hydrogen peroxide, and antioxidant enzyme activity also occurred during salinity. Arg treatment changed the pattern of biochemical responses in the cells grown at high salinity by directing carbon flow to the biosynthesis of non-reducing sugars instead of starch, lowering levels of hydrogen peroxide, and downregulating antioxidant enzyme activity, but the levels of lipid peroxidation, glycerol, and β-carotene remained nearly unchanged. These results suggest that Arg treatment alleviates salinity-induced oxidative stress in D. salina cells by modifying carbon partitioning and inducing signaling molecules rather than antioxidant enzymes.