Bioprocessing of Agricultural Residues as Substrates and Optimal Conditions for Phytase Production of Chestnut Mushroom, Pholiota adiposa, in Solid State Fermentation

Use of agricultural waste for optimization of protease production by Pleurotus djamor and evaluation of its anthelmintic activity

Pleurotus djamor is an edible mushroom that produces proteases. However, the production of these enzymes needs to be optimized and applied in experimental models. This study aimed to optimize the production of proteases by Pleurotus djamor using agricultural waste and to evaluate the anthelmintic activity of proteases in vitro. Solid-state fermentation optimized protease production, with wheat bran as the substrate. For this, the central composite design (CCD) was used. The proteolytic activity was determined after the preparation of the cell-free crude extract. In addition, eggs of the helminths Taenia solium and Moniezia sp. were used to evaluate the in vitro anthelmintic activity of the proteases. The results showed that moisture significantly influenced (p < 0.01) protease production. On the other hand, within the evaluated intervals, the incubation time was non-significant (p > 0.05). The enzymes led to a significant reduction (p < 0.01) in T. solium and Moniezia sp. eggs, with reductions of 33.44% and 45.43%, respectively, compared to the control with denatured enzymes. The results suggest the action of proteases in the degradation of helminth eggs, demonstrating their potential for biochemistry control.

The Domestication and Cultivation of Pholiota adiposa and Its High-Temperature Adaptability: Enhancing the Utilization of Agricultural Residues and Grain Nutrition in Northeast China

Pholiota adiposa is a macrofungi that is rich in nutrients and has a delicious taste. Eating more can improve human immunity and inhibit cancer. However, the P. adiposa yield is low and cannot meet market demand. Therefore, strain improvement was carried out by exploring the mechanism of stress adaptation in P. adiposa. In addition, fermentation of the four common grains by P. adiposa mycelia increased their nutrient content and improved their antioxidant capacity. The results revealed that the growth of the mycelium was greatest when sucrose was used as the carbon source at 25 °C. At 35 °C, the MDA content and cellulase enzyme activity of the mycelia decreased by 27.6% and 40.8%, respectively, from 2 to 4 days, and the SOD, CAT, and GR enzyme activities increased by 31.6%, 49.2%, and 1.2%, respectively. The fermentation results revealed that the soluble protein content, reducing sugar content, and DPPH free radical scavenging ability of the fermented grains were significantly greater than those of the unfermented grains. This study can be used to cultivate macrofungi with environmental adaptability and provides a basis for the utilization of biological waste and increased food nutrition.

Optimization of phytase production by Penicillium oxalicum in solid-state fermentation for potential as a feed additive

The study aims to statistically optimize the phytase production by Penicillium oxalicum PBG30 in solid-state fermentation using wheat bran as substrate. Variables viz. pH, incubation days, MgSO4, and Tween-80 were the significant parameters identified through the Plackett-Burman design (PBD) that majorly influenced the phytase production. Further, central composite design (CCD) method of response surface methodology (RSM) defined the optimum values for these factors i.e., pH 7.0, 5 days of incubation, 0.75% of MgSO4, and 3.5% of Tween-80 that leads to maximum phytase production of 475.42 U/g DMR. Phytase production was also sustainable in flasks and trays of different sizes with phytase levels ranging from 394.95 to 475.42 U/g DMR. Enhancement in phytase production is 5.6-fold as compared to unoptimized conditions. The in-vitro dephytinization of feed showed an amelioration in the nutritive value by releasing inorganic phosphate and other nutrients in a time-dependent manner. The highest amount of inorganic phosphate (33.986 mg/g feed), reducing sugar (134.4 mg/g feed), and soluble protein (115.52 mg/g feed) was achieved at 37 °C with 200 U of phytase in 0.5 g feed for 48 h. This study reports the economical and large-scale production of phytase with applicability in enhancing feed nutrition.

Synchronous reducing anti-nutritional factors and enhancing biological activity of soybean by the fermentation of edible fungus Auricularia auricula

Auricularia auricula fermentation was performed to reduce anti-nutritional factors, improve nutritional components, and enhance biological activity of soybean. Results showed that the contents of raffinose, stachyose, and trypsin inhibitor were significantly decreased from initial 1.65 g L-1, 1.60 g L-1, and 284.67 μg g-1 to 0.14 g L-1, 0.35 g L-1, and 4.52 μg g-1 after 144 h of fermentation, respectively. Simultaneously, the contents of polysaccharide, total phenolics, and total flavonoids were increased, and melanin was secreted. The isoflavone glycosides were converted to their aglycones, and the contents of glyctin and genistin were decreased from initial 1107.99 μg g-1 and 2852.26 μg g-1 to non-detection after 72 h of fermentation, respectively. After 96 h of fermentation, the IC50 values of samples against DPPH and ABTS radicals scavenging were decreased from 17.61 mg mL-1 and 3.43 mg mL-1 to 4.63 mg mL-1 and 0.89 mg mL-1, and those of samples inhibiting α-glucosidase and angiotensin I-converting enzyme were decreased from 53.89 mg mL-1 and 11.27 mg mL-1 to 18.24 mg mL-1 and 6.78 mg mL-1, respectively, indicating the significant increase in these bioactivities. These results suggested A. auricula fermentation can enhance the nutritional quality and biological activity of soybean, and the fermented soybean products have the potential to be processed into health foods/food additives.

Innovative applications and therapeutic potential of oilseeds and their by-products: An eco-friendly and sustainable approach

The risk of inadequate management of agro-waste is an emerging challenge. However, the economic relevance of agro-waste valorization is one of the key strategies to ensure sustainable development. Among the agro-waste, oilseed waste and its by-products are usually seen as mass waste after the extraction of oils. Oilseed by-products especially oilseed cakes are a potential source of protein, fiber, minerals, and antioxidants. Oilseed cakes contain high value-added bioactive compounds which have great significance among researchers to develop novel foods having therapeutic applications. Moreover, these oilseed cakes might be employed in the pharmaceutical and cosmetic industries. Thus, as a result of having desirable characteristics, oilseed by-products can be more valuable in wide application in the food business along with the preparation of supplements. The current review highlights that plentiful wastes or by-products from oilseeds are wasted if these underutilized materials are not properly valorized or effectively utilized. Hence, promising utilization of oilseeds and their wastes not only assists to overcome environmental concerns and protein insecurity but also helps to achieve the goals of zero waste and sustainability. Furthermore, the article also covers the production and industrial applications of oilseeds and by-products along with the potential role of oilseed cakes and phytochemicals in the treatment of chronic diseases.

Structural analysis and in vitro antitumor effect of polysaccharides from Pholiota adiposa

Pholiota adiposa is an edible chestnut mushroom with many health benefits, such as antioxidant and anticancer activity. In this paper, polysaccharides were extracted from Pholidota adiposa using an acid extraction process. The crude polysaccharide was purified using DEAE-cellulose chromatography, and two polysaccharide fractions of SPAP2-1 and SPAP2-2 were obtained. The structure was characterized using UV, GPC, GC, FT-IR, methylation, and NMR analysis. Monosaccharide component analysis indicated that SPAP2-1 (19 kDa) and SPAP2-2 (20 kDa) contained mannose, glucose, and galactose with different molecular ratios. Their antitumor effects were investigated using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium (MTT) assay, Annexin V-fluorescein isothiocyanate (FITC), propidium iodide (PI) staining, and flow cytometry. By analyzing the changes in the cells, SPAP2-1 caused damage and changed the proliferation rate of HeLa cells. SPAP2-1 showed strong interference to the cell cycle of HeLa cells and induced cell apoptosis. Overall, these results suggested that polysaccharides from Pholiota adiposa, especially SPAP2-1, may have the potential to be used as a tumor cell inhibitor, which needs further study.

Influence of Pholiota adiposa on gut microbiota and promote tumor cell apoptosis properties in H22 tumor-bearing mice

Hepatocellular carcinoma (HCC) is a common type of cancer-prevalent worldwide-and one of the causes of cancer-related deaths. In this study, ethanol extracts from Pholiota adiposa (EPA) were used to identify possible targets for HCC treatment and their effects on intestinal microflora were analyzed. Methods: Male mice were randomly assigned to groups-the model group, cyclophosphamide (25 mg/kg/d), and EPA groups, in which the mice were categorized based on the different concentrations of each compound (100, 200, and 300 mg/kg/day). Relevant biochemical indicators were detected using ELISA, H&E staining, and TUNEL assay. Four tumor apoptosis-related proteins and genes, Cleaved Caspases, BAX, Bcl-2, and VEGF, were detected by immunohistochemical staining, western blotting, and RT-PCR. The total genomic DNA was obtained from the contents of the small intestine and colon and was sequenced. The V3 + V4 regions of bacterial 16 s rDNA (from 341 to 806) were amplified. Results: The tests revealed that EPA exhibited antitumor activity in vivo by promoting apoptosis and inhibiting angiogenesis. Moreover, EPA treatment could increase beneficial and decrease harmful microflorae. These results demonstrate that EPA may be a potential therapy for HCC.

Agro-Industrial Wastes: A Substrate for Multi-Enzymes Production by Cryphonectria parasitica

This study aims to produce a mix of enzymes through Solid State Fermentation (SSF) of raw materials. Four different, easily available, agro-industrial wastes were evaluated as SSF substrates for enzymes production by Cryphonectria parasitica (Murr.) Barr. environmental strains named CpA, CpB2, CpC4, and CpC7. Among the tested wastes, organic wheat bran for human use and wheat bran for animal feed better supports C. parasitica growth and protease production without any supplements. SDS-PAGE analyses highlighted the presence of three bands corresponding to an extracellular laccase (77 kDa), to the endothiapepsin (37 kDa), and to a carboxylesterase (60.6 kDa). Protease, laccase, and esterase activities by C. parasitica in SSF were evaluated for 15 days, showing the maximum protease activity at day 9 (3955.6 AU/gsf,). Conversely, the best laccase and esterase production was achieved after 15 days. The C. parasitica hypovirulent CpC4 strain showed the highest laccase and esterase activity (93.8 AU/gsf and 2.5 U/gsf, respectively). These results suggest the feasibility of a large-scale production of industrially relevant enzymes by C. parasitica strains in SSF process on low value materials.

Valorization of Lignocellulosic Wastes to Produce Phytase and Cellulolytic Enzymes from a Thermophilic Fungus, Thermoascus aurantiacus SL16W, under Semi-Solid State Fermentation

Agricultural wastes are lignocellulosic biomasses that contain high mineral and nutrient contents. This waste can be used as a raw material in industrial enzyme production by microbial fermentation. Phytase is an important enzyme used in animal feed to enhance the amount of phosphorus available for the growth and overall health improvement of monogastric animals. Fungi offer high potential as an effective source in the production of various extracellular enzymes. In this study, the production of lignocellulolytic enzymes (endoglucanase and xylanase) and phytase by a thermophilic fungus, namely Thermoascus aurantiacus strain SL16W, was evaluated using sixteen different Thai agricultural forms of waste under conditions of high temperature (45 °C). Semi-solid state fermentation was used in the production experiments. The results of this study reveal that the highest phytase activity (58.6 U/g substrate) was found in rice bran, whereas the highest degrees of activity of endoglucanase and xylanase were observed in wheat bran and red tea leaves at 19 and 162 U/g substrate, respectively. Consequently, the optimal conditions for phytase production of this fungus using rice bran were investigated. The results indicate that the highest phytase yield (58.6 to 84.1 U/g substrate) was observed in rice bran containing 0.5% ammonium sulfate as a nitrogen source with 10 discs of inoculum size at a cultivation period of 9 days at 45 °C and moisture content of 95%. Notably, the phytase yield increased by 1.71-fold, while endoglucanase and xylanase were also increased by 1.69- and 1.12-fold, respectively. Furthermore, the crude enzyme obtained from the optimal condition was extracted. The crude enzyme extract was then separately added to red tea leaves, rice straw, corncobs, palm residue, and peanut husks. Subsequently, total reducing sugar and phosphorus contents were determined. The results indicate that the highest level of reducing sugar (122.6 mg/L) and phosphorus content (452.6 mg/L) (p < 0.05) were obtained in palm residue at 36 and 48 h, respectively, after the addition of the crude enzyme extract. This study has provided valuable information on a potentially eco-friendly way to valorize agricultural waste into value-added products as industrial enzymes.