Search Results (51)

American ginseng (Panax quinquefolium L.) residue from the extraction industry can be dried and mixed with rice bran as media for black truffle solid-state fermentation to enhance reuse and bioactive functions. Different ratios of rice bran (R) and American ginseng residue (G) mixtures were used as solid-state media for 5 weeks of black truffle fermentation, and then their bio-component contents and whitening effects were analyzed. Finally, four drying methods—hot air drying (HA), microwave drying (MW), hot air-assisted radio frequency (HARF) drying, and radio frequency vacuum (RFV) drying—were assessed to optimize drying efficiency for fermented medium. The results showed that using a 3:1 ratio of rice bran and American ginseng residue as the medium increased the crude polysaccharide and flavonoid contents by approximately threefold and enhanced the ginsenoside Rg3 content about twelvefold. Additionally, the 100 µg/mL ethanol extract of the fermented product inhibited 70% of tyrosinase activity and reduced the melanin area on zebrafish embryos by 42.74%. In the drying study, RFV drying R2G1 required only 13 min without exceeding 70 °C, demonstrating superior drying efficiency, temperature control, and low energy consumption. Overall, this study demonstrates the potential of black truffle fermentation of solid-state media from rice bran and American ginseng residue mixtures for whitening applications and highlights RFV drying as an efficient method for by-products. Full article

This study developed a solid-state fermentation system based on Trichoderma harzianum, which significantly enhanced the nutritional value of distiller’s grain (DG) feed through a multi-stage synergistic treatment process. During the cellulase production phase, rice husk was used as an auxiliary material, and specific degradation of DGs was effectively enhanced. Through optimization using response surface methodology, the optimal enzyme production conditions were determined. The filter paper enzyme activity reached a peak of 1.45 U/gds (enzyme activity per gram of dry substrate) when the moisture content was 53%, the fermentation time was 3 days, and the Tween-80 dosage was 0.015 mL/g (dry weight basis). Under these conditions, the crude enzyme solution was used to hydrolyze DGs. Compared to original DGs, the content of reducing sugars increased by 10.75%. In the stage of protein production, segmented hydrolysis fermentation (SHF) and simultaneous saccharification fermentation (SSF) processes were employed using yeast. The results showed that SSF pathway showed better performance, and the true protein content reached 15.16% after 11 days, an increase of 41.5% compared to the control. Finally, through secondary fermentation regulated by Lactobacillus fermentum, the flavor of the feed was significantly improved. This study innovatively integrated bio-enzymatic hydrolysis and multi-strain synergistic fermentation technologies, providing a novel strategy for the efficient and sustainable production of protein feed based on DGs. Full article

The aim of this study was to increase the availability of high-value-added compounds by applying S. cerevisiae to rice bran substrates (whole and defatted). The substrates were subjected to solid-state fermentation with yeast (3% pp⁻¹) and water (30%) for up to 8 h at 30 °C. The fermentation of brown rice bran resulted in increased ash, protein, and fiber contents, while the fermentation of defatted rice bran led to higher lipid and fiber levels. Additionally, the fermentation process influenced the mineral profile. The phenolic compound content of the fermented brown rice bran increased over fermentation, reaching values of 1165 µg g⁻¹ per sample. Brown rice bran fermented for 6 h yielded the best results in terms of nutrient and bioactive compound availability. Principal component analysis (PCA) revealed correlations between variables, suggesting that modifications could further enhance the availability of various compounds. Full article

In the field, substantial quantities of insect pathogenic fungal conidia (5 × 10¹²/ha) are usually applied for the control of pests. In this regard, attempts are being made to obtain higher yields of conidia to make the process viable. One of the approaches is to induce microcycle conidia (MC) production. In a solid-state fermentation on rice, the SYB-grown inoculum with more pseudomycelia of B. bassiana enhanced MC production almost 5 times compared to the aerial conidia (AC) within 10 days. A chitosan (CNP) and alginate–chitosan (ACNP) nanocoating of MC increased the overall temperature and UV stability. The % cumulative mortalities of Spodoptera litura larvae over 10 d were 83 ± 8.0, 90 ± 5.0, 83 ± 5.0, and 90 ± 6 for AC-, MC-, CNP- coated MC and ACNP-coated MC, respectively. Using probit analysis, the LT₅₀ values were 5.8, 6.0, 7.5, and 6.3 d for AC, MC, CNPs-MC, and ACNPs-MC, respectively. It was observed that chitin deacetylase (CDA) plays a significant role in increasing MC formation. The higher relative proportion of total CDA over chitosanase activity (higher CDA: chitosanase activity ratio) was found to be correlated with the microcycle conidiation. Full article

Red yeast rice is a nutraceutical fermented product used worldwide for the symptomatic relief of dyslipidemia and cardiovascular disease. However, the fermentation-induced lipid transformation from rice to red yeast rice remains unclear. Herein, an ultra-high performance liquid chromatography coupled with hybrid quadrupole-orbitrap mass spectrometry method was developed for the comprehensive lipid analysis during fermentation. A total of 246 lipids fall in 21 subclasses were annotated in rice and red yeast rice, including 37 lysophospholipids, 14 phospholipids, 29 diglycerides, 114 triglycerides and fatty acid (15 species), ceramide (12 species), hexosylceramide (3 species), sitosterol ester (2 species), monogalactosyldiacylglycerol (2 species), digalactosyldiacylglycerol (2 species), monogalactosylmonoacylglycerol (8 species), digalactosylmonoacylglycerol (5 species), coenzyme Q (1 species), acyl hexosyl campesterol ester (1 species), and acylcarnitine (1 species). Results showed that lipid profiles changed, and new lipid species emerged. Notably, 18 medium- and long-chain triacylglycerols and triacylglycerols with short-chains were tentatively identified. These triacylglycerols also show the effects of body fat accumulation reduction, and hypolipidemic and hypoglycemic activities. Furthermore, lipid species that were profoundly changed were quantified, and the dynamic changes were investigated. This study clarified the molecular species and compositional changes in fermented rice from lipid aspect. Full article

Upcycling low-cost agricultural by-products into valuable and sustainable alternative feeding materials could secure human food-supply chains with a low carbon footprint. This study explored increasing the feeding value of camelina meal (CAM) mixed with wheat bran (WB), soybean hulls (SH), and rice hulls (RH) for monogastric animals via solid-state fermentation (SSF) using white rot fungus Trametes versicolor. Experiments evaluated fungal growth, amino acid profiles, structural carbohydrates, glucosinolates, phytate and in vitro dry matter digestibility (IVDMD). Weight loss analysis indicated that fungal growth was more active in WB/CAM and SH/CAM substrates than RH/CAM. Significant phytic acid degradation and near-complete glucosinolate elimination improved CAM feed quality across all substrates. Fermentation increased total and essential amino acids in the SH/CAM mixture, while reductions occurred in WB/CAM and RH/CAM mixtures. SH/CAM fermentation caused substantial cellulose and hemicellulose degradation, resulting in a 44% IVDMD increase. Conversely, RH/CAM fermentation decreased IVDMD despite a reduction in cellulose, possibly due to protein degradation. This study demonstrates the potential of T. versicolor-mediated SSF to enhance CAM and other agricultural residues’ feeding value for monogastric animal applications. Full article

The soju (Korean traditional distilled liquor) market is increasing worldwide. However, in contrast to well-explored distilled liquors, including baijiu (China) and shochu (Japan), soju is less investigated, with limited research on its aroma characteristics. To facilitate better understanding of the aroma characteristics of soju, this study aims to overview recent research on the flavor characteristics of soju and compare data with those of baijiu and shochu, well-established products in the market. Soju is generally made using rice and nuruk (a traditional Korean fermentation starter). Previous studies have reflected that the aroma characteristics vary with raw materials’ nutrition percentages, microbial taxa influenced in fermentation starters, and/or pressure reduction during distillation. The research on the aroma characteristics of baijiu, characterized by solid-state fermentation involving qu (a traditional Chinese fermentation starter), is focused on differences in regional characteristics of the flavor type. Research on the aroma characteristics of shochu has primarily demonstrated that the microbial community could contribute significantly to the development of specific aromatic compounds and/or attributes. Moreover, the association of the aroma characteristics of baijiu and shochu with their volatile compound development by the determination of selective ingredients has been examined. Understanding the current research progress can potentially facilitate the improvement in the aroma characteristics of soju. Full article

Cereal wastes such as rice bran and cereal dust are valuable yet underutilised by-products of grain processing. This study aimed to bio-convert these wastes into bacterial cellulose (BC), an emerging sustainable and renewable biomaterial, via an inexpensive solid-state fermentation (SSF) pre-treatment using three mould isolates. Medium substitution by directly using untreated rice bran or cereal dust did not significantly increase the yield of bacterial cellulose produced by Novacetimonas sp. (NCBI accession number PP421219) compared to the standard Hestrin–Schramm (HS) medium. In contrast, rice bran fermented with Rhizopus oligosporus yielded the highest bacterial cellulose (1.55 ± 0.6 g/L dry weight) compared to the untreated control (0.45 ± 0.1 g/L dry weight), demonstrating an up to 22% increase in yield. Using the SSF process, the media production costs were reduced by up to 90% compared to the standard HS medium. Physicochemical characterisation using SEM, EDS, FTIR, XPS, XRD, and TGA was performed to gain insights into the internal structure, morphology, and chemical bonding of differently produced BC, which revealed comparable biopolymer properties between BC produced in standard and waste-based media. Hence, our findings demonstrate the effectiveness of fungal SSF for transforming abundant cereal waste into BC, providing a circular economy solution to reduce waste and convert it into by-products to enhance the sustainability of the cereal industry. Full article

This study aimed to formulate a black bean soy sauce using black beans and black rice as media for the solid-state fermentation of white truffle. Various proportions of these media (4:0, 3:1, 2:2, 1:3, and 0:4) were prepared, with methionine concentrations (0, 0.3, 0.6, 0.9, 1.2, and 1.5%) serving as precursors for a 4-week solid-state fermentation to analyze the aroma profiles. GC-MS analysis showed that samples with 1.5% methionine exhibited significantly higher levels of sulfur-containing volatile compounds compared to those without methionine. GC-IMS analysis revealed that a 2:2 ratio of black beans to black rice produced the most enriched aroma. Lower methionine levels improved mycelial growth, with 0.3% methionine yielding the richest aroma components. After fermentation, the white truffle products were sterilized using autoclaving, hot air assisted radio frequency (HARF), and high pressure processing (HPP), followed by freeze drying. GC-IMS analysis showed that HPP samples had an aroma closest to fresh samples, whereas HARF and autoclave resulted in similar aromas. However, 24 h freeze drying significantly diminished the aroma, resulting in no significant difference in aroma among the freeze-dried products treated with different sterilization methods. Full article

Grain processing produces many by-products, including wheat bran, wheat germ and rice bran, which are rich in carbohydrates, proteins and trace elements. In this study, these grain-derived by-products were used as raw materials to conduct solid-state fermentation using mixed strains of Aspergillus kawachii and Rhizopus oryzae, and the potential immunomodulatory and anti-allergic properties of fermented product were evaluated. Solid-state fermentation of a grain by-product mixture, consisting of rice bran, wheat bran, and wheat germ in a 2:1:1 weight ratio, using both A. kawachii L1 and R. oryzae L1 at 26 °C for 5 days, significantly increased the total phenolic, flavonoid, and amino acid contents. The anti-allergic activity of aqueous extract of the fermented product was evaluated in murine models of food allergy and delayed-type hypersensitivity. Oral administration of the fermented product extract (100–200 mg/kg) notably alleviated allergic symptoms such as diarrhea and histopathological changes in the intestines. Moreover, the extract effectively reduced allergen-specific serum antibodies, suppressed splenic cytokine secretion, and mitigated tissue edema and inflammation induced by allergens. Importantly, the extract induced the production of IL-10 and TGF-β, which are well-known cytokines primarily secreted by regulatory T cells. These results underscore the promising immunomodulatory effects of A. kawachii and R. oryzae fermented grain product, suggesting their potential as functional foods or additives for managing allergic disorders, with implications for future therapeutic and dietary applications. Full article

Hot air-assisted radio frequency (HARF) is considered a rapid heating process. In order to improve the circular economy of agricultural byproducts, this study used different proportions of HARF stabilized rice bran (R) from milling rice, HARF dried ginseng residue (G) from ultrasonic extraction, and peanut residue (P) from HARF roasting and oil extraction as the Hericium erinaceus solid-state fermented media. Then, the whitening effects of water extracts from media and fermented products were analyzed. First, the surface temperature of 1 kg rice bran exceeded 90 °C after 3 min of 5 kW HARF heating, effectively deactivating lipase. The combinations of 1 kg of rice bran with 0.5, 1, 1.5, and 2 kg of ginseng residue (85% moisture content) were dried using 5 kW HARF. Each of the drying rates was about 27 g/min, and the drying periods were 14, 30, 46, and 62 min, respectively, which were used to reduce the moisture content below 10%. Compared to traditional air drying for ginseng residue, HARF drying may save up to 96% of time and 91% of energy consumption. Then, the ratio of dried R, G, and P was 4:1:1, mixed with 45% moisture as solid-state media for Hericium erinaceus and 5 weeks of cultivation at 25 °C. In comparison to the control group, the water extracts at 100 µg/mL from media R4G1, R4G1P1, and fermented HER4G1P1 products exhibited tyrosinase inhibition of 29.7%, 52.4%, and 50.7%, respectively. These extracts also reduced the relative melanin area of 78 hpf zebrafish embryos by 21.57%, 40.20%, and 58.03%, respectively. Therefore, HARF can quickly dry agricultural byproducts as media for Hericium erinaceus solid-state fermentation while also providing a significant whitening effect for cosmetic applications. Full article

Trichoderma is a widely recognized plant-growth-promoting fungus that has been extensively utilized in various agricultural applications. However, research on the economic production of Trichoderma spores and their effects on tea cuttings must be further advanced. In this study, T. guizhouense NJAU 4742 (NJAU 4742) emerged as a growth-promoting strain for tea cuttings, and the spore-production conditions of NJAU 4742 attained through solid-state fermentation (SSF) using tea residues were optimized. In a pot experiment, nursery substrates containing different concentrations of NJAU 4742 spores were tested for their influence on tea cutting growth and the rhizosphere fungal community. The optimal conditions for spore yield were determined as a 7:3 (w/w) ratio of tea residue to rice bran, a material thickness of 3 cm, an inoculum concentration of 15% (v/w), and an incubation time of 4 days, resulting in a spore count of 1.8 × 10⁹ CFU/g. Applying NJAU 4742 spore products significantly increased the biomass of tea cuttings and influenced the fungal community composition. Moreover, higher concentrations of NJAU 4742 spores yielded better growth performance, and applying nursery substrate with 1.0 × 10⁷ CFU/mL spores was the most economically viable option. Notably, among the top ten fungal genera with the highest relative abundance, Trichoderma showed a positive correlation with the fresh weight of tea cuttings, while the others exhibited a negative correlation. Overall, utilizing tea residue for SSF to produce NJAU 4742 was a feasible approach, and the application of NJAU 4742 spores enhanced the growth of tea cuttings by increasing the relative abundance of Trichoderma. Full article

Solid by-products with lignocellulosic structures are considered appropriate substrates for solid-state fermentation (SSF) to produce enzymes with diverse industrial applications. In this work, brewer’s spent grain (BSG), rice husk (RH), and vine shoot trimmings (VSTs) were employed as substrates in SSF with Aspergillus niger CECT 2088 to produce cellulases, xylanases, and amylases. The addition of 2% (NH₄)₂SO₄ and 1% K₂HPO₄ to by-products had a positive effect on enzyme production. Substrate particle size influenced enzyme activity and the overall highest activities were achieved at the largest particle size (10 mm) of BSG and RH and a size of 4 mm for VSTs. Optimal substrate composition was predicted using a simplex centroid mixture design. The highest activities were obtained using 100% BSG for β-glucosidase (363 U/g) and endo-1,4-β-glucanase (189 U/g), 87% BSG and 13% RH for xylanase (627 U/g), and 72% BSG and 28% RH for amylase (263 U/g). Besides the optimal values found, mixtures of BSG with RH or VSTs proved to be alternative substrates to BSG alone. These findings demonstrate that SSF bioprocessing of BSG individually or in mixtures with RH and VSTs is an efficient and sustainable strategy to produce enzymes of significant industrial interest within the circular economy guidelines. Full article

A fruiting body of a basidiomycete fungus was discovered growing on chopped Ficus nitida tree trunks in the student housing on the Assiut University campus during the course of this inquiry and a normal collecting operation in the Assiut Governorate, Egypt. Following the growth of the basidioma’s inner tissue on PDA, fungal mycelial growth was achieved. Internal transcribed spacer region (ITS) sequencing has allowed for the identification of the fungus as Tomophagus colossus. On the dry weight basis, chemical analysis of T. colossus AUMC 14536 basidioma revealed that it contains 28.81% carbohydrates, 25.34% crude fats, 23.44% crude fibers, 20.64% crude proteins, and 3.02% ash, in addition to potassium, phosphorus, calcium, selenium, iron, and zinc (133.59, 114.46, 6.27, 3.08, 1.28, and 0.73 mg/100 g dry weight, respectively). The total phenolic compounds (39.26 mg/g) and total flavonoids (5.62 mg/g) were also evaluated. The basidioma extract’s antioxidant activity was assessed as %DPPH radical scavenging activity with an IC50 of 4.15 µg/mL compared with a 1.89 µg/mL IC50 of ascorbic acid. In solid-state fermentation (SSF), the fungus could ferment broad bean straw, palm leaf hay, rice husk, rice straw, sugarcane bagasse, and wheat bran to produce endoglucanase, exoglucanase, laccase, pectinase, and xylanase in substantial amounts. Specific activity exhibited the highest values for endoglucanase (81.48 U/mg), exoglucanase (114.35 U/mg), pectinase (81.94 U/mg), and xylanase (70.18 U/mg) on the rice husk, while the peak of laccase activity (94.27 U/mg) was gained on bean straw. This is the first assessment of the organism’s nutritional value, amino acid content, antioxidant activity, and enzymatic capabilities in Egypt. Full article

Plant feedstuffs are the main ingredients of animal feed. Owing to food–feed competition, increasing the utilization efficiency of these feedstuffs is important for animal nutrition. This can be achieved via solid-state fermentation (SSF). SSF of a plant feedstuff mixture (PFM) (25% rapeseed meal, soybean meal, rice bran, and sunflower meal) by three fungi (Aspergillus ibericus MUM 03.29, Aspergillus niger CECT 2088, and Aspergillus niger CECT 2915) resulted in an increase in protein content by 5%, irrespective of fungi, a reduction in cellulose content by 9 to 11%, and of hemicellulose content by 21 to 34%, relative to unfermented PFM. Enzyme production was measured: the highest cellulase (123.7 U/g), xylanase (431.8 U/g), and beta-glucosidase (117.9 U/g) activity were achieved with A. niger CECT 2088. Principal component analysis showed a positive correlation between all fermented PFMs and enzyme production, protein content, digestibility, and fiber reduction. Bioprocessing of the PFM by SSF increased its nutritional value and digestibility, making it more appealing for animal feeds. Full article