Upgrading the Bioactive Potential of Hazelnut Oil Cake by Aspergillus oryzae under Solid-State Fermentation.

Hazelnut oil cake (HOC) has the potential to be bioactive component source. Therefore, HOC was processed with a solid-state fermentation (SSF) by Aspergillus oryzae with two steps optimization: Plackett-Burman and Box-Behnken design. The variables were the initial moisture content (X1: 30-50%), incubation temperature (X2: 26-37 °C), and time (X3: 3-5 days), and the response was total peptide content (TPC). The fermented HOC (FHOC) was darker with higher protein, oil, and ash but lower carbohydrate content than HOC. The FHOC had 6.1% more essential amino acid and benzaldehyde comprised 48.8% of determined volatile compounds. Fermentation provided 14 times higher TPC (462.37 mg tryptone/g) and higher phenolic content as 3.5, 48, and 7 times in aqueous, methanolic, and 80% aqueous methanolic extract in FHOC, respectively. FHOC showed higher antioxidant as ABTS+ (75.61 µmol Trolox/g), DPPH (14.09 µmol Trolox/g), and OH (265 mg ascorbic acid/g) radical scavenging, and α-glucosidase inhibition, whereas HOC had more angiotensin converting enzyme inhibition. HOC showed better water absorption while FHOC had better oil absorption activity. Both cakes had similar foaming and emulsifying activity; however, FHOC produced more stable foams and emulsions. SSF at lab-scale yielded more bioactive component with better functionality in FHOC.

Molecular identification of Shiitake (Lentinula edodes), analysis and production of beta-glucan using beech wood sawdust waste.

Lentinula edodes has the ability to grow and produce bioactive compounds on industrial by-products. This study aimed to produce B-glucan of cell wall Shiitake on Beechwood Sawdust (BWS) through a two-step procedure, which included fermentation and B-glucan extraction and purification. Shiitake mushrooms are cultivated by solid-state fermentation (SSF) using the Jamas method to increase the purity of B-glucan. The fermented substrate was first separated and then hydrolyzed by sodium hydroxide (NaOH) (10 M, 1 M), followed by acid hydrolysis extraction. The structure and purity of B-glucan were confirmed by FTIR, NMR, and AFM spectroscopy. The fungus used was molecularly identified by the 18 s rRNA method. Shiitake mushroom was produced by SSF using BWS and high purity ß-glucan was extracted from the produced polysaccharide in the amount of 67.33 mg/g. FTIR, NMR, and AFM analyses proved the production of beta-glucan, and based on molecular identification, it was determined that the mushroom used was Lentinula edodes. The results obtained show that SSF is a valuable technology for the production of biomass and polysaccharides by utilizing the strain of L. edodes. To the best of our knowledge, the yield reported is the highest by the strain of L. edodes using SSF.

Production of milk-coagulating protease by fungus Pleurotus djamor through solid state fermentation using wheat bran as the low-cost substrate.

Proteases are enzymes that hydrolyze peptide bonds present in proteins and peptides. They are widely used for various industrial applications, such as in the detergent, food, and dairy industries. Cheese is one of the most important products of the dairy industry, and the coagulation stage is crucial during the cheese-making process. Enzymatic coagulation is the most common technique utilized for this purpose. Microbial enzymes are frequently used for coagulation due to their advantages in terms of availability, sustainability, quality control, product variety, and compliance with dietary and cultural/religious requirements. In the present study, we identified and subsequently characterized milk coagulant activity from the fungus Pleurotus djamor PLO13, obtained during a solid-state fermentation process, using the agro-industrial residue, wheat bran, as the fermentation medium. Maximum enzyme production and caseinolytic activity occurred 120 h after cultivation. When the enzyme activity against various protease-specific synthetic substrates and inhibitors was analyzed, the enzyme was found to be a serine protease, similar to elastase 2. This elastase-2-like serine protease was able to coagulate pasteurized whole and reconstituted skim milk highly efficiently in the presence and absence of calcium, even at room temperature. The coagulation process was influenced by factors such as temperature, time, and calcium concentration. We demonstrate here, for the first time, an elastase-2-like enzyme in a microorganism and its potential application in the food industry for cheese production.

Effects of fermented and unfermented aging corn on ruminal fermentation, bacterial communities, lactation performance and plasma metabolites in Holstein cows.

Aging reduces the nutritional value of corn grain, which may be improved by fermentation prior to use. This study investigated the effects of replacing conventional corn (CC) with aging corn (AC) and fermented aging corn (FAC) in the diets of lactating Holstein cows. Six healthy third-parity Holstein cows were used in a replicated 3 × 3 Latin square experiment with 21-day periods. Cows were fed twice and milked twice daily. The cows were randomly divided into three treatment groups: (1) CC diet: a diet with 23.6% starch in diet DM containing 24.0% conventional corn; (2) AC diet: a diet with 23.5% starch in diet DM containing 24.0% aging corn replacing conventional corn; and (3) FAC diet: a diet with 23.2% starch in diet DM containing 24.6% fermented aging corn replacing conventional corn. The diets were formulated to be isonitrogenous and contained identical roughage. The FAC treatment increased the starch digestibility compared with AC. Feeding FAC increased the concentrations of total volatile fatty acid compared with CC and AC and decreased the molar proportion of acetate compared with AC. At the family level, the relative abundance of Prevotellaceae was higher on FAC than CC. The relative abundance of Succinivibrionaceae was lower on FAC than on CC and AC. Besides, at the genera level, the relative abundance of Succinivibrionaceae_UCG_002 in the rumen was higher on AC than CC and FAC. The relative abundance of Prevotella and Ruminococcus was higher on FAC than CC and AC. The relative abundance of Succinivibrionaceae_UCG_001 was lower on FAC than CC. The Simpson index was lower on FAC than CC and AC. The FAC treatment increased the milk yield (34.0, 33.7, and 35.2 kg/d for CC, AC, and FAC group, respectively) and protein yield, and thus, energy-corrected milk production was increased, and at the same time, decreased the somatic cell score compared with CC and AC. The AC treatment increased the malondialdehyde concentration in plasma compared with CC and FAC. The concentrations in plasma of triglyceride and malondialdehyde were lower on FAC than AC. The immunoglobulin G concentration in plasma was higher on FAC than CC and AC. Overall, feeding AC resulted in decreased plasma antioxidant capacity compared with CC, whereas feeding FAC altered the relative abundance of bacteria in the rumen and improved starch digestibility, ruminal bacterial diversity, lactation performance, plasma antioxidant capacity and immune competence compared with AC in dairy cows.

A novel approach to produce soy protein isolate: Direct enzymatic hydrolysis of high-temperature soybean meal using proteinase produced by microbial solid-state fermentation.

This study proposed a novel extraction method for soy protein isolate, which involved solid-state fermentation of high-temperature soybean meal. The proteinases secreted by microorganisms acted on the high-temperature soybean meal, making the SPI easier to extract. The study concludes that Bacillus amyloliquefaciens subsp. plantarum CICC 10265 could be used for solid-state fermentation of soybean meal, and the fermentation effect was good, with a yield of 41.91 % for SPI. Compared to the direct extraction of SPI from high-temperature soybean meal, the yield had increased by 130.19 %. Meanwhile, we also conducted research on the losses during the SPI extraction process. Through experiments, the study identified the patterns of protease activity changes and microbial colony growth during solid-state fermentation of soybean meal by Bacillus amyloliquefaciens subsp. plantarum CICC 10265. It was concluded that extracting SPI after 8 h of fermentation is more suitable. The experimental results indicated that the total amino acid content of SPI extracted from fermented soybean meal was 2.1 % higher compared to SPI extracted from low-temperature soybean meal. The extracted SPI also met the microbial standards.

Innovative sustainable bioreactor-in-a-granule formulation of Trichoderma asperelloides.

The advancement of fungal biocontrol agents depends on replacing cereal grains with low-cost agro-industrial byproducts for their economical mass production and development of stable formulations. We propose an innovative approach to develop a rice flour-based formulation of the beneficial biocontrol agent Trichoderma asperelloides CMAA1584 designed to simulate a micro-bioreactor within the concept of full biorefinery process, affording in situ conidiation, extended shelf-life, and effective control of Sclerotinia sclerotiorum, a devastating pathogen of several dicot agricultural crops worldwide. Rice flour is an inexpensive and underexplored byproduct derived from broken rice after milling, capable of sustaining high yields of conidial production through our optimized fermentation-formulation route. Conidial yield was mainly influenced by nitrogen content (0.1% w/w) added to the rice meal coupled with the fermentor type. Hydrolyzed yeast was the best nitrogen source yielding 2.6 × 109 colony-forming units (CFU)/g within 14 days. Subsequently, GControl, GLecithin, GBreak-Thru, GBentonite, and GOrganic compost+Break-Thru formulations were obtained by extrusion followed by air-drying and further assessed for their potential to induce secondary sporulation in situ, storage stability, and efficacy against Sclerotinia. GControl, GBreak-Thru, GBentonite, and GOrganic compost+Break-Thru stood out with the highest number of CFU after sporulation upon re-hydration on water-agar medium. Shelf-life of formulations GControl and GBentonite remained consistent for > 3 months at ambient temperature, while in GBentonite and GOrganic compost+Break-Thru formulations remained viable for 24 months during refrigerated storage. Formulations exhibited similar efficacy in suppressing the myceliogenic germination of Sclerotinia irrespective of their concentration tested (5 × 104 to 5 × 106 CFU/g of soil), resulting in 79.2 to 93.7% relative inhibition. Noteworthily, all 24-month-old formulations kept under cold storage successfully suppressed sclerotia. This work provides an environmentally friendly bioprocess method using rice flour as the main feedstock to develop waste-free granular formulations of Trichoderma conidia that are effective in suppressing Sclerotinia while also improving biopesticide shelf-life. KEY POINTS: • Innovative "bioreactor-in-a-granule" system for T. asperelloides is devised. • Dry granules of aerial conidia remain highly viable for 24 months at 4 °C. • Effective control of white-mold sclerotia via soil application of Trichoderma-based granules.

Valorization of Date By-Products: Enhancement of Antioxidant and Antimicrobial Potentials through Fermentation.

The by-products from three varieties of dates-Mozafati, Sayer, and Kabkab-were subjected to solid-state fermentation using Aspergillus niger alone or in co-culture with Lactiplantibacillus plantarum or Limosilactobacillus reuteri to enhance their phenolic and flavonoid content, along with antioxidant and antimicrobial activities. Solid-state fermentation, being environmentally friendly and cost-effective, is particularly suitable for agricultural residues. Significant increases (p < 0.05) in total polyphenol content (TPC), total flavonoid content (TFC), and antioxidant power were observed post-fermentation, especially under co-culture conditions. The highest TPC (12.98 ± 0.29 mg GA/g) and TFC (1.83 ± 0.07 mg QE/g) were recorded in the co-culture fermentation of by-products from the Mozafati and Sayer varieties, respectively. HPLC analysis revealed changes in polyphenol profiles post-fermentation, with reductions in gallic and ferulic acids and increases in caffeic acid, p-coumaric acid, rutin, quercetin, and kaempferol. FT-IR analysis confirmed significant alterations in polyphenolic functional groups. Enhanced antimicrobial activity was also observed, with inhibition zones ranging from 8.26 ± 0.06 mm for Kabkab to 17.73 ± 0.09 mm for Mozafati. These results suggest that co-culture solid-state fermentation is a promising strategy for valorizing date by-products, with potential applications in nutraceuticals and/or pharmaceutical products and as valuable additives in the food industry.

Kinetics of cellulase-free endo xylanase hyper-synthesis by Aspergillus Niger using wheat bran as a potential solid substrate.

The present study deals with the production of cellulase-free endoxylanase by Aspergillus niger ISL-9 using wheat bran as a solid substrate. Endoxylanase was produced under a solid-state fermentation. Various growth parameters were optimized for the improved production of the enzyme. The Substrate level of 15 g was optimized as it provided the fungus with balanced aeration and nutrition. Among the six moisture contents investigated, Moisture Content 5 (MC5) was optimized (g/l: malt extract, 10; (NH4)2HPO4, 2.5; urea, 1.0) and 10 mL of MC5 was found to give the highest production of endoxylanase. The pH and time of incubation were optimized to 6.2 and 48 h respectively. The Inoculum size of 2 mL (1.4 × 106 spores/mL) gave the maximum enzyme production. After optimization of these growth parameters, a significantly high endoxylanase activity of 21.87 U/g was achieved. Very negligible Carboxymethylcellulase (CMCase) activity was observed indicating the production of cellulase-free endoxylanase. The notable finding is that the endoxylanase activity was increased by 1.4-fold under optimized conditions (p ≤ 0.05). The overall comparison of kinetic parameters for enhanced production of endoxylanase by A. niger ISL-9 under Solid State Fermentation (SSF) was also studied. Different kinetic variables which included specific growth rate, product yield coefficients, volumetric rates and specific rates were observed at 48, 72 and 96 h incubation time and were compared for MC1 and MC5. Among the kinetic parameters, the most significant result was obtained with volumetric rate constant for product formation (Qp) that was found to be optimum (1.89 U/h) at 72 h incubation period and a high value of Qp i.e.1.68 U/h was also observed at 48 h incubation period. Thus, the study demonstrates a cost-effective and environmentally sustainable process for xylanase production and exhibits scope towards successful industrial applications.

Effect of Solid-State Fermentation of Hericium erinaceus on the Structure and Physicochemical Properties of Soluble Dietary Fiber from Corn Husk.

Corn husk, a by-product of corn starch production and processing, contains high-quality dietary fiber (DF). Our study compares and analyzes the impact of Hericium erinaceus solid-state fermentation (SSF) on the structure and physicochemical characteristics of soluble dietary fiber (SDF) of corn husks. The study also investigates the kinetics of SSF of H. erinaceus in this process. The scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) results revealed significant structural changes in corn husk SDF before and after fermentation, with a significant elevation in the functional group numbers. The data indicate that the fermented corn husk SDF's water-holding, swelling, and oil-holding capacities increased to 1.57, 1.95, and 1.80 times those of the pre-fermentation SDF, respectively. Additionally, the results suggest that changes in extracellular enzyme activity and nutrient composition during SSF of H. erinaceus are closely associated with the mycelium growth stage, with a mutual promotion or inhibition relationship between the two. Our study offers a foundation for corn husk SDF fermentation and is relevant to the bioconversion of maize processing by-products.

Exploring the Impact of Solid-State Fermentation on Fava Bean Flour: A Comparative Study of Aspergillus oryzae and Rhizopus oligosporus.

Fava bean (Vicia faba L.) is a protein-rich pulse with high nutritional value, but its functional and sensory characteristics limit its application in foods. Solid-state fermentation (SSF) can modify the composition of plant proteins, modulate its functionality, and enhance the sensory aspects. In this study, fava bean flour (FB) was fermented with Aspergillus oryzae and Rhizopus oligosporus to produce FBA and FBR, respectively, ingredients with distinct nutritional, functional, and aroma characteristics. The protein content increased by 20% in FBA and 8% in FBR, while fat levels rose more significantly in FBR (+40%). The overall content of fermentable oligo-, di-, mono-saccharides, and polyols (FODMAPs) decreased by 47% (FBA) and 57% (FBR), although polyol production by A. oryzae was observed. SSF improved the nutritional profile of FBA and FBR, with a notable increase in the concentration of essential amino acids observed, and a reduction in most antinutrients, with the exception of trypsin inhibitors. SSF resulted in the formation of aggregates, which increased the particle size and reduced protein solubility. Emulsions prepared with the fermented ingredients separated faster, and the foaming capacity of both FBA and FBR was decreased, but an increase in water-holding capacity was observed. SSF resulted in the production of predominantly savoury-associated aroma compounds, with compounds characteristic of metallic and mouldy aromas reduced. These results indicate the potential of SSF to transform FB with enhanced nutritional value and improved sensory and functional properties.

Solid-State Fermentation Engineering of Traditional Chinese Fermented Food.

Solid-state fermentation (SSF) system involves solid, liquid, and gas phases, characterized by complex mass and heat transfer mechanisms and microbial complex interactions. The SSF processes for traditional Chinese fermented foods, such as vinegar, soy sauce, and baijiu primarily rely on experience, and most of the operations are replaced by auto machine now. However, there is still a lack of engineering in-depth study of the microbial process of SSF for complete process control. To meet the demands of smart manufacturing and green production, this paper emphasizes the engineering analysis of the mechanisms behind SSF. It reviews the progress in the engineering aspects of Chinese traditional SSF, including raw material pretreatment, process parameter detection, mathematical model construction, and equipment innovation. Additionally, it summarizes the challenges faced during intelligent upgrades and the opportunities brought by scientific and technological advancements, proposing future development directions. This review provides an overview of the SSF engineering aspects, offering a reference for the intelligent transformation and sustainable development of the Chinese traditional SSF food industry.

Effects of solid-state fermentation product of yeast supplementation on liver and intestinal health, and resistance of common carp (Cyprinus carpio) against spring viraemia carp virus.

This study aimed to investigate the effects of solid-state fermentation products of yeast (SFPY) on liver and intestinal health and disease resistance of common carp (Cyprinus carpio). A total of 200 common carp with an initial average weight of 2.55 ± 0.004 g were divided into 5 groups (4 replications per group and 10 fish per replication), and were fed with one of five diets, including a control diet and 4 diets supplemented with 2‰ (Y2), 3‰ (Y3), 4‰ (Y4), or 5‰ (Y5) SFPY, respectively, for 8 weeks. Results indicated that, the addition of SFPY to the diet of common carp did not affect the growth performance or survival rate of fish (P = 0.253). Interestingly, with the addition of SFPY, the triacylglycerol (TAG) content of the liver presented a linear decreasing tendency (P = 0.004), with significantly decreased in Y4 and Y5 groups (P = 0.035) compared with control. Serum lipopolysaccharide (LPS) content and diamine oxidase (DAO) activity presented a negative linear relationship with the addition of SFPY (P = 0.015, P = 0.030), while serum lipopolysaccharide binding protein (LBP) content first decreased and then increased (P < 0.001). The total antioxidant capacity (T-AOC) in the intestine of fish increased continuously with increasing SFPY supplementation (P = 0.026), reaching the highest level in Y5 group. The villus height in all experimental groups were significantly higher than that in the control group (P < 0.001). Furthermore, compared to the control, adding 3‰ SFPY to the control diet of common carp significantly increased the relative abundance of Fusobacteria (P = 0.018) and decreased that of Proteobacteria (P = 0.039) at phylum level, and increased the relative abundance of Cetobacterium (P= 0.018) and decreased that of Shewanella (P = 0.013) at genus level. Compared with the control, the relative mRNA expression level of spring viraemia of carp virus N protein (SVCV -n) in the kidney was lower than that of the control group without significance and bottomed out in Y4 group (P = 0.138). In conclusion, dietary SFPY enhanced the SVCV resistance capacity of common carp by improving liver and intestinal health and modulating the gut microbiota. Thus, SFPY is a potential feed additive to be used in aquaculture to reduce the huge economic loss of common carp due to SVCV disease. Based on liver TAG content and intestinal villus height, the optimal addition level of SFPY was 3.02‰ and 2.72‰, respectively.

New biocatalyst produced from fermented biomass: improvement of adsorptive characteristics and application in aroma synthesis.

This study presents a novel approach to producing activated carbon from agro-industrial residues, specifically cocoa fruit peel, using solid-state fermentation (SSF) with Aspergillus niger. The process effectively degrades lignin, a major impediment in traditional activated carbon production, resulting in a high-quality carbon material. This carbon was successfully utilized for enzyme immobilization and aroma synthesis, showcasing its potential as a versatile biocatalyst. The study meticulously evaluated the physical and chemical attributes of activated carbon derived from fermented cocoa peel, alongside the immobilized enzymes. Employing a suite of analytical techniques-electrophoresis, FTIR, XRD, and TG/DTG the research revealed that fermentation yields a porous material with an expansive surface area of 1107.87 m2/g. This material proves to be an excellent medium for lipase immobilization. The biocatalyst fashioned from the fermented biomass exhibited a notable increase in protein content (13% w/w), hydrolytic activity (15% w/w), and specific activity (29% w/w), underscoring the efficacy of the fermentation process. The significant outcome of this research is the development of a sustainable method for activated carbon production that not only overcomes the limitations posed by lignin but also enhances enzyme immobilization for industrial applications. The study's findings have important implications for the agro-industrial sector, promoting a circular economy and advancing sustainable biotechnological processes.

Improving the extraction yield of essential oil from Pimenta dioica (L.) Merr. using Aspergillus niger ATCC 1004 enzyme blend.

The objective of this work was to optimize the application of an enzymatic blend produced by Aspergillus niger ATCC 1004 on the Pimenta dioica fruits for essential oil extraction. The enzyme blend was obtained from the fermentation of cocoa bean shells, an agro-industrial residue. The effects of the enzymatic pre-treatment on the extraction yield, the chemical composition of the oil through gas chromatography, and the fruit structure through scanning electron microscopy (SEM) were assessed. A Doehlert design was used to optimize the process conditions, resulting in an extraction with 117 mL of enzyme during 77 min, which increased the extraction yield by 387.5%. The chemical composition was not altered, which proves that the enzyme blend preserves the quality of the essential oil extracted. The content of eugenol (70%), the major compound in the P. dioica essential oil, had a great increase in its concentration (560%). The enzyme activity analyses showed the presence of endoglucanase (0.4 U/mL), exoglucanase (0.25 U/mL), ß-glucosidase (0.19 U/mL), and invertase (135.08 U/mL). The microscopy analyses revealed changes in the morphology of fruit surface due to the enzymatic action. These results demonstrate the great potential of using enzyme blends produced by filamentous fungi from agro-industrial residues for the essential oils extraction of interest for the pharmaceutical and food industries.

Production and characterization of acidophilic xylanase from wood degrading white rot fungus by solid-state fermentation of wheat straw.

Xylanases (EC 3.2.1.8) catalyze the breakdown of xylan, which is the second most abundant polysaccharide in plant cell walls. Biological catalysts have gained greater global attention than chemical catalysts in different industrial processes because they are highly selective, easy to control and have a negligible environmental impact. The aim of this study was to investigate the xylanolytic potential of white-rot fungi, optimize their physicochemical conditions and characterize the resulting xylanase. Sixty-eight white-rot fungus (WRF) isolates were screened for their xylanolytic potential and growth conditions for maximal xylanase production using cheap agricultural residue (wheat straw) as the sole carbon source. Five WRF isolates with high xylanase yields (73.63 ± 0.0283-63.6 ± 0.01247 U/ml) were selected by qualitative and quantitative screening methods. The optimum xylanase production occurred at pH 5.0 and 28 °C. Solid-state fermentation (SSF) yielded a high amount of xylanase. The highest xylanase activity (80.9-61.274 U/mL) was recorded in the pH range of 5.0-6.5 and at 50 °C. The metal ions Mg2+, Ca2+ and Mn2+ enhanced the activity of xylanase (127.28-110.06 %), while Cu2+, Fe2+ and K+ inhibited the activity with 43.4-17 % losses. The km and Vmax were 0.32-0.545 mg/mL and 86.95-113.63 µmol/min/mg, respectively. This finding indicates that wheat straw can be used for large-scale xylanase production under SSF conditions. The pH and temperature profiles and stabilities indicate that the xylanase produced in the present study can be applied in food and animal feed industries.

In vitro efficacy of Rosa damascena solid state fermentation liquid and water extract on skin care.

BACKGROUND: As a medicinal and food homologous plant, Rosa damascena is not only highly ornamental, but also rich in a variety of active ingredients such as polyphenols and flavonoids. It is widely used in cosmetics, food and pharmaceutical industries. OBJECTIVE: To study the in vitro efficacy of Rosa damascena solid state fermentation liquid (RDF) and water extract (RDE). METHODS: Firstly, the effect of RDF and RDE on the proliferation rate of B16F10 cells was detected by CCK-8 method, and the melanin content was measured by sodium hydroxide lysis method to evaluate the whitening effect of them. Finally, the antioxidant, anti-wrinkling and soothing effects of RDF and RDE were evaluated by biochemical methods in vitro. RESULTS: RDF and RDE within a certain concentration range (0.05%-0.5%) had no effect on the proliferation of B16F10 cells. Compared with Rosa damascena extract (RDE), RDF showed significant effects on bleaching, antioxidant, anti-wrinkling and soothing, among which 0.5% RDF showed the best effect. CONCLUSION: Both RDF and RDE at a certain concentration have effect on skin care in vitro, but the effect of RDF is more significant than that of RDE.

In situ fortification of cereal by-products with vitamin B12: An eco-sustainable approach for food fortification.

Vitamin B12 deficiency poses significant health risks, especially among populations with limited access to animal-based foods. This study explores the utilisation of cereal bran by-products, wheat (WB) and oat bran (OB), as substrates for in situ vitamin B12 fortification through solid-state fermentation (SSF) using Propionibacterium freudenreichii. The impact of various precursors addition, including riboflavin, cobalt, nicotinamide and DMBI on vitamin B12 production, along with changes in microbial growth, chemical profiles, and vitamin B12 yields during fermentation was evaluated. Results showed that WB and OB possess favourable constituents for microbial growth and vitamin B12 synthesis. The substrates supplemented with riboflavin, cobalt, and DMBI demonstrated enhanced B12 production. In addition, pH levels are essential in microbial viability and cobalamin biosynthesis. Monosaccharides and organic acids play a crucial role, with maltose showing a strong positive association with B12 production in OB, while in WB, citric acid exhibits significant correlations with various factors.

Enhanced saccharification levels of corn starch using as a strategy a novel amylolytic complex (AmyHb) from the thermophilic fungus Humicola brevis var. thermoidea in association with commercial enzyme.

Amylases represent a versatile group of catalysts that are used for the saccharification of starch because they can hydrolyze the glycosidic bonds of starch molecules to release glucose, maltose, and short-chain oligosaccharides. The amylolytic complex of the thermophilic filamentous fungus Humicola brevis var. thermoidea (AmyHb) was produced, biochemically characterized, and compared with the commercial amylase Termamyl. In addition, the biotechnological application of AmyHb in starch saccharification was investigated. The highest production was achieved using a wheat bran medium at 50 °C for 5-6 days in solid-state fermentation (849.6 ± 18.2 U·g-1) without the addition of inducers. Optimum amylolytic activity occurred at pH 5.0 at 60 °C, and stability was maintained between pH 5.0 and 6.0, with thermal stability at 50-60 °C, especially in the presence of Ca2+. These results were superior to those found with Termamyl. Both enzymes were strongly inhibited by Hg2+, Cu2+, and Ag+; however, AmyHb displayed increased activity in the presence of Mn2+ and Na+. In addition, AmyHb showed greater tolerance to a wide range of ethanol concentrations. AmyHb appears to be a complex consisting of glucoamylase and α-amylase, based on its substrate specificity and TLC. The hydrolysis tests on cornstarch flour showed that the cocktail of AmyHb50% + Termamyl50% significantly increased the release of glucose and total reducing sugars (36.6%) when compared to the enzymes alone. AmyHb exhibited promising physicochemical properties and good performance with commercial amylase; therefore, this complex is a biotechnological alternative candidate for the bioprocessing of starch sources.

Comparison of primary and secondary metabolites and antioxidant activities by solid-state fermentation of Apios americana Medikus with different fungi.

This study compared the nutritional components, isoflavones, and antioxidant activities by solid-sate fermentation of Apios americana Medikus (AAM) with seven different fungi. The total fatty acid contents increased from 120.5 mg/100 g (unfermented AAM, UFAAM) to 242.0 to 3167.5 mg/100 g (fermented AAM, FAAM) with all fungi. In particular, the values of total fatty acids were highest (26.3-fold increase) in the FAAM with Monascus purpureus. The amount of total free amino acids increased from 591.69 mg/100 g (UFAAM) to 664.38 to 1603.07 mg/100 g after fermentation except for Monascus pilosus and Lentinula edodes. The total mineral contents increased evidently after fermentation with M. purpureus, F. velutipes, and Tricholoma matsutake (347.36 â†’ 588.29, 576.59, and 453.32 mg/100 g, respectively). The UFAAM predominated isoflavone glycosides, whereas glycoside forms were converted into aglycone forms after fermentation by fungi. The bioconversion rates of glycoside to aglycone were excellent in the FAAM with M. pilosus, M. purpureus, F. velutipes, and T. matsutake (0.01 â†’ 0.69, 0.50, 0.27, and 0.31 mg/g, respectively). Furthermore, the total phenolic contents, total flavonoid contents, and antioxidant activities by the abovementioned FAAM were high except for L.edodes. This FAAM can be used as a potential food and pharmaceutical materials.