Pleurotus eryngii (P. eryngii) can secrete large amount of hydrolytic and oxidative enzymes to degrade lignocellulosic biomass. In spite of several researches on the individual lignolytic enzymes, a direct deconstruction of lignocellulose by enzyme mixture is not yet possible. Identifying more high-performance enzymes or enzyme complexes will lead to efficient in vitro lignocelluloses degradation. In this report, secretomic analysis was used to search for the new or interesting enzymes for lignocellulose degradation. Besides, the utilization ability of P. eryngii to ramie stalk substrate was evaluated from the degradation of cellulose, hemicellulose, and lignin in medium and six extracellular enzymes activities during different growth stages were discussed. The results showed that a high biological efficiency of 71% was obtained; cellulose, hemicelluloses, and lignin decomposition rates of P. eryngii were 29.2, 26.0, and 51.2%, respectively. Enzyme activity showed that carboxymethyl cellulase, xylanase, laccase, and peroxidase activity peaks appeared at the primordial initiation stage. In addition, we profiled a global view of the secretome of P. eryngii cultivated in ramie stalk media to understand the mechanism behind lignocellulosic biomass hydrolysis. Eighty-seven nonredundant proteins were identified and a diverse group of enzymes, including cellulases, hemicellulases, pectinase, ligninase, protease, peptidases, and phosphatase implicated in lignocellulose degradation were found. In conclusion, the information in this report will be helpful to better understand the lignocelluloses degradation mechanisms of P. eryngii.
Abstract Background: The high cost of cellulase is one of the main obstacles hindering the large-scale biorefining of lignocellulosic biomass. Screening strains with high cellulase producing capability and improving enzymatic hydrolysis technology are important methods to reduce the cost of enzymes. A powerful strategy to lignocellulose as a feedback combined with different enzymes synergism can reduces the time of designing high-efficient enzyme mixtures and significantly improve saccharification of specific substrates. Results: After optimization, the maximum CMCase and FPA produced by Trichoderma reesei reached to 6.06 IU/mL and 0.085 IU/mL, respectively. The hydrolysis capability of Trichoderma reesei was induced at the presence of ramie stalk not wheat bran. Synergistic effect was observed as enzymes produced by Trichoderma reesei and Aspergillus niger were incubated together, and the highest reducing sugars yield was achieved when enzyme cocktail was prepared at the ratio of 1:1. In particular, reducing sugars yield reached to 417 mg/g dry substrate was achieved after hydrolyzing the substrate by prepared enzyme cocktail, which were 1.36 - 3.35 folds higher than different single enzymes. Conclusion: This study indicated that (1) the carbon source exhibited a directional induction effect on the types of cellulolytic enzymes secreted by microorganisms; (2) cellulolytic enzymes from different sources could synergistically strengthen the enzymatic hydrolysis of lignocellulosic materials, providing a clue for the preparation and compounding of cellulolytic enzymes.
This study aimed to investigate the effects of fermentation with Lactiplantibacillus plantarum Picp-2, Saccharomyces cerevisiae SY or their combination on the antioxidant and cytoprotection activities of Lonicerae japonicae flos, and reveal metabolite change based on untargeted metabolomics. Compared with the unfermented group, the ·OH scavenging rate of L. plantarum Picp-2 and co-fermentation groups were increased by 1.23- and 1.13-fold, respectively, and the DPPH· scavenging rate of SY group was increased by 1.10-fold, moreover, the cytoprotection activity of co-fermentation group was increased by 1.32-fold. Metabolomics indicated that the contents of benzoic acids, cinnamic acids, quininic acids, flavonoids and amino acids were significantly changed after fermentation. Moreover, the proliferation of L. plantarum was enhanced by S. cerevisiae, whereas the growth of S. cerevisiae was inhibited possibly due to suppression of its galactose metabolism by L. plantarum. Besides, correlation analysis showed that demethyltexasin, ferulic acid, chlorogenic acid, and eriodictyol were positively correlated with antioxidant activities, while taxifolin, paeonol and riboflavin were positively correlated with cytoprotection activity.
This study investigated the effects of three different single-strain probiotics Lactiplantibacillus plantarum XD117, Lacticaseibacillus paracasei LC-37, and Lacticaseibacillus rhamnosus LGG, on the quality of hempseed fermented milk. The main findings were that adding probiotics increased the inhibition rate of α-glucosidase and pancreatic lipase in hempseed fermented milk significantly. Non-targeted metabolomic correlation analysis results confirmed that 14 substances, including three flavonoids, six amino acids and their derivatives, and five short peptides, were positively correlated with the hypoglycemic and hypolipidemic activities of hempseed fermented milk. Furthermore, a total of 59 volatile flavor compounds were identified, including aldehydes, alcohols, ketones, acids, and esters, and the role mapping of different probiotic communities was provided. These results can guide the development of hempseed fermented milk with unique flavor, rich probiotic content, and significant functional characteristics.
Hericium erinaceus has attracted tremendous interest owing to its compelling health-promoting properties. However, breeding of elite cultivars of H. erinaceus is hindered by the lack of a genetic and molecular toolbox. Here, we performed resequencing analysis of 127 F1 single-spore isolates and constructed the first high-resolution genetic map of H. erinaceus. With the use of recombination bins as markers, an ultradense genetic map consisting of 1,174 bins (including 37,082 single-nucleotide polymorphisms) was generated. This newly developed genetic map covered 1,096.5 cM, with an average bin spacing of 0.95 cM. High collinearity between genetic map and H. erinaceus genome assembly was revealed by aligning scaffolds to this genetic map using bin markers as anchors. The application of this newly developed genetic map in quantitative trait locus (QTL) mapping was also elucidated, and four QTLs for monokaryon growth were recovered. One QTL, mgr1, which contributes 12.1% of growth variations, was located near the mating type A (MAT-A) loci. Overall, this newly constructed high-resolution genetic map (or bin map) could be used as reference in future genetic, genomic, and breeding studies on H. erinaceus.
'%3e%3cpath fill='%23012169' d='M0 0v30h60V0z'/%3e%3cpath stroke='%23fff' stroke-width='6' d='m0 0 60 30m0-30L0 30'/%3e%3cpath stroke='%23C8102E' stroke-width='4' d='m0 0 60 30m0-30L0 30' clip-path='url(%23b)'/%3e%3cpath stroke='%23fff' stroke-width='10' d='M30 0v30M0 15h60'/%3e%3cpath stroke='%23C8102E' stroke-width='6' d='M30 0v30M0 15h60'/%3e%3c/g%3e%3c/svg%3e)
'/%3e%3cuse xlink:href='%23a' transform='rotate(23.036 .093 25.536)'/%3e%3cuse xlink:href='%23a' transform='rotate(45.87 1.273 16.18)'/%3e%3cuse xlink:href='%23a' transform='rotate(69.945 .996 12.078)'/%3e%3cuse xlink:href='%23a' transform='rotate(20.66 -19.689 31.932)'/%3e%3c/svg%3e)
