Ligninolytic characteristics of Pleurotus ostreatus cultivated in cotton stalk media

Abstract

Biodelignification is widely regarded as a low-efficiency process because it is usually slow and difficult to control. To improve its efficiency and understand its mechanism, the present study analyzed the delignification characteristics of Pleurotus ostreatus grown on a cotton stalk medium. The results demonstrated that all strains of P. ostreatus can selectively degrade the cotton stalk lignin. When cultured in a cotton stalk medium for 60 days, P. ostreatus degraded lignin primarily during its mycelium growth with up to 54.04% lignin degradation and produced laccase and manganese dependent peroxidase with high activity levels at the peaks of 70.17 U/ml and 62.39 U/ml, respectively, but no detectable lignin peroxidase. The results of nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy analyses of significant changes in lignin structure revealed that syringyl (S) lignin units were more degraded than guaiacyl (G) lignin units, with a significantly elevated G/S ratio. The Gas Chromatography-Mass Spectrometer analysis of low-molecular-weight compounds revealed that the delignification resulted in the formation of alcohols, organic acids, benzodiazepines, and alkanes. Identified benzodiazepines implied the degradation of G and S units of lignin. These findings will help to improve the efficiency of biodelignification and expand our understanding of its mechanism.

A Comprehensive Analysis of the Thermo-Chemical Properties of Sudanese Biomass for Sustainable Applications

“…The value of kenaf bast fibers was the same as that found in the previous study [31]. The lignin content of cotton stalks was lower than that found in the literature [32] and equal to the value reported in the previous study [33].…”

Modulation of the Gut Microbiota with Prebiotics and Antimicrobial Agents from Pleurotus ostreatus Mushroom

“…P. ostreatus also has a great ability to bio-degrade organic pollutants by mycoremediation [4,32] or removing sulfonamides from real wastewater [33]. This kind of mushroom can also produce ligninolytic enzymes, which biodelignificate the agro-wastes like cotton stalks [34,35]. Polysaccharides, protein glycoproteins, lectins, high molecular weight-fed fats, small molecule secondary alkaloids, metabolite esters, flavonoids, polyphenols, and triglyceridesols' bioactive compounds can be found in large numbers in the P. ostreatus mushroom [36].…”

Novel techniques for the mass production of nutritionally improved, fungus‐treated lignocellulosic biomass for ruminant nutrition

“…Pleurotus ostreatus , during the process of lignin degradation, produces metabolites like alcohol and organic acids, which promote mycelium growth in the substrate 35,36 . Li et al 35 . also established a positive relation between delignification and mycelium growth.…”

“…There are also reports suggesting that lignin degradation caused by white‐rot fungi increases mycelium growth, resulting in an increase in the CP content. Pleurotus ostreatus , during the process of lignin degradation, produces metabolites like alcohol and organic acids, which promote mycelium growth in the substrate 35,36 . Li et al 35 .…”