Evaluation of different agricultural wastes for the production of polysaccharides from Oudemansiella raphanipes and its antioxidant properties

Oudemansiella raphanipes (OR) is a commercial mushroom which possesses high nutritional value and excellent and unique flavors. In this study, various agricultural wastes were utilized as substitute materials in the low-cost and high-yield production of mycelia biomass and polysaccharides by liquid fermentation. The sawdust, wheat bran, apple pomace, sugarcane, and corn particles were employed to cultivate OR, using the potato dextrose broth as control. Additionally, a preliminary characterization and in vitro antioxidant activities of partial purified OR polysaccharides were investigated. The substrate of sugarcane was suitable for mycelia growth of OR, with high yield of mycelia biomass and polysaccharides content. In vitro antioxidant activity assays demonstrated that OR polysaccharides could effectively scavenge 2,2 '-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and 1,1-diphenyl-2-picrylhydrazyl radicals. OR polysaccharides had configuration as revealed by Fourier transform infrared, and was mainly composed of fucose (Fuc), rhamnose (Rha), arabinose (Ara), galactose (Gal), glucose (Glc), xylose (Xyl), mannose (Man), ribose (Rib), and galacturonic acid (Gal-UA), with mass percentages of 3.29%, 0.64%, 1.09%, 16.03%, 72.69%, 0.56%, 3.18%, 0.93%, and 1.59%, respectively. This study may offer support for decreasing the cost of OR polysaccharides production and dealing with these agricultural wastes.

Automated summary

In this study, agricultural wastes were used to cultivate Oudemansiella raphanipes mycelia biomass and polysaccharides through low-cost and high-yield liquid fermentation. Sugarcane waste was found to be the most suitable substrate for mycelia growth and resulted in high yield of biomass and polysaccharides. The polysaccharides from Oudemansiella raphanipes showed promising antioxidant activity. This research provides insights into reducing polysaccharide production costs and addressing agricultural waste.