Phenoloxidase activity of micromycetes strains isolated from the rhizosphere of vegetable leguminous crops

Abstract

Relevance. Microscopic fungi exhibit the greatest exoenzymatic activity, and xylotrophs are capable of possessing a complex of oxidase and hydrolase enzymes to destroy lignin.Methods. Among the soil micromycetes isolated from the rhizosphere of annual leguminous crops, a search was made for strains that are promising from the point of view of effective microorganism technology, in order to create optimal conditions for increasing soil fertility and crop yields. The detection of total phenol oxidase activity was carried out according to the method of Bavendamm, cultivating the strains on microbiological agar with the addition of an aromatic lignin derivative (0.06% tannin) and the growth factor was calculated. The cellulase activity of the strains was judged by the degree of hydrolysis of the filter paper. Alternaria alternata, Bipolaris, Botrytis fabae, Cunninghamella echinulata, Curvularia lunata, Macrophoma phaseolicola, Trichoderma koningii, Trichoderma viride and Ulocladium botrytis strains were found to cleave lignin and cellulose.Results. When comparing the phenoloxidase activity of the strains, it was proposed to take into account the growth factor, expressed as the ratio of the diameter of the colony on the substrate with the addition of tannin to the diameter of the colony without tannin. Thus, perspective strains of T. koningii and U. botrytis strains with respect to the complex activity of enzymes were identified. The strains C. lunata, A. alternata and B. australiensis showed high cellulase activity. The strain of non-pathogenic soil fungus C. echinulata has the ability to degrade lignin