FourPleurotus spp.fungi (P. diamor, P. eryngii, P. sajor-caju, P. citrinopileatus) were compared for their potential to improve nutritional value of corn stover as ruminant feed. Corn stover was inoculated with the fungi under solid-state conditions and their results showed thatP. sajor-cajuandP. eryngiiwere better than the other two species ofPleurotuswith respect to decreasing the acid detergent lignin (ADL) (8.99 vs 9.88 vs 10.16 vs 10.46). In contrast,P. eryngiihad lower ability to degrade cellulose (13.38%). Corn stover treated withP. citrinopileatushad the highest crude protein (CP) content (7.65%), whereas treatment withP. sajor-cajuresulted in the highest increase in essential amino acids (55.11%). Although fungal pre-treatment of lignocellulosic biomass does not always result in high-quality feed, overall,P. eryngiiandP. sajor-cajuimproved the nutritive value of corn stover as a ruminant feed.

Lignin degradation is important for enhancing the digestibility and improving the nutritive quality of ruminant feeds. White rot fungi are well known for their bioconversion of lignocellulosic biomass. The objective of this paper was to evaluate whether Lentinus sajor-caju, Pleurotus ostreatus, Phyllotopsis rhodophylla, Pleurotus djamor, Pleurotus eryngii, and Pleurotus citrinopileatus treatments altered the chemical compositions of highland barley straw constituents and enhanced their nutritional value as a ruminant feed. All white rot fungi significantly increased the relative crude protein (CP), ethyl ether extract (EE), starch, soluble protein (SP), and non-protein nitrogen (NPN) contents but decreased the ash, neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), and acid detergent insoluble protein (ADFIP) contents. In addition, L. sajor-caju treatment increased (p < 0.001) the levels of PA, PB₂, PB₃, CA, CB₁, CB₂, and CNSC, but reduced (p < 0.001) the PC and CC in the solid-state fermentation of highland barley straw. Maximum ligninlysis (50.19%) was optimally produced in the presence of 1.53% glucose and 2.29% urea at 22.72 ℃. The in vitro dry matter digestibility and total volatile fatty acid concentrations of fermented highland barley straw, as well as the fermentability, were optimized and improved with L. sajor-caju, which degraded the lignocellulose and improved the nutritional value of highland barley straw as a ruminant feed.

Due to the ecotoxicity of 17β-estradiol (E2), residual E2 in the environment poses potential risks to human and animal health and ecosystems. Biodegradation is considered one of the most effective strategies to remove E2 from the environment. Here, a novel, efficient E2-degrading bacterial strain Microbacterium resistens MZT7 was isolated from activated sludge and characterized. The genome of strain MZT7 contained 4,011,347 bp nucleotides with 71.26% G + C content and 3785 coding genes. There was 86.7% transformation efficiency of 10 mg/L E2 by strain MZT7 after incubation for 5 d at optimal temperature (30 °C) and pH (7.0). This strain was highly tolerant to ranges in pH (5.0–11.0), temperature (20–40 °C), and salinity (2–8%). Adding sources of carbon (glucose, maltose, sucrose, or lactose) or nitrogen sources (urea, peptone, or beef extract) promoted the degradation of E2 by strain MZT7. However, when yeast extract was added as a nitrogen source, the degradation efficiency of E2 was inhibited. Metabolites were analyzed by LC-MS and three metabolic pathways of E2 degradation were proposed. Further, the intermediates dehydroepiandrosterone and androsta-1,4-diene-3,17-dione were detected, as well as identification of kshB and fadD3 genes by KEGG, confirming one E2 degradation pathway. This study provided some insights into E2 biodegradation.

Environmental estrogen pollution has long been a concern due to adverse effects on organisms and ecosystems. Biodegradation is a vital way to remove estrogen, a strain of Lysinibacillus sp. was isolated, numbered strain GG242. The degradation rate of 100 mg·L⁻¹ 17β-estradiol (E2)) > 95% in one week, and compared with extracellular enzymes, intracellular enzymes have stronger degradation ability. Strain GG242 can maintain a stable E2 degradation ability under different conditions (20–35 °C, pH 5–11, salinity 0–40 g·L⁻¹). Under appropriate conditions (30 °C, pH 8, 1 g·L⁻¹ NaCl), the degradation rate increased by 32.32% in one week. Based on the analysis of transformation products, inferred E2 was converted via two distinct routes. Together, this research indicates the degradation potential of strain GG242 and provides new insights into the biotransformation of E2.

Lentinus sajor-caju has shown potential for the bioconversion of lignocellulosic biomass in various substrates. Here, we evaluated whether L. sajor-caju affects the lignocellulosic biomass, in vitro fermentation and antioxidant properties of Astragalus membranaceus var. mongholicus (AMM) stems. The lignocellulosic biomass content and the antioxidant activity of AMM stems were determined by scanning electron microscopy, chemical component analysis, in vitro fermentation and LC-MS metabolomics after 30 days of fermentation by L. sajor-caju at 25 °C. L. sajor-caju significantly altered the rigid structure of the stems. Compared with the control condition, the lignocellulose contents were significantly reduced (p < 0.001) and improved in vitro digestibility and total volatile fatty acids. In total, 624 differential metabolites, including 201 up-regulated and 423 down-regulated, were identified in unfermented and fermented comparison groups. Correlation analysis indicated that there were strongly correlations of the total phenolic content and total antioxidant capacity. Meanwhile, the differential metabolites were primarily associated with antioxidant activity, with 4(3H)-quinazolinone, dihydrocarvyl acetate and jaceoside being the most representative. In summary, L. sajor-caju altered the composition of the cell wall of AMM stems, thereby enhancing their antioxidant activity.