Antifungal protein determination for submerged cultures of the medicinal mushroom <i>Ganoderma lucidum</i> (Ganodermataceae) with activity over the phytopathogen fungus Mycosphaerella fijiensis (Mycosphaerellaceae)

Abstract

Banana is one of the most important edible crops in the world, however, it’s attacked by different pathogens, one of the most prominent of these is the fungus Mycosphaerella fijiensis, causal agent of Black Sigatoka. The environmental and economic issues related to the pesticides used for its control have encouraged the search for cleaner alternative biomolecules. Previous studies were made by the Biotechnology group from the Universidad de Antioquia searching for a biological alternative for the control of M. fijiensis; in these the antifungal capacity of the fungus Ganoderma lucidum was determined as an antagonist and then as a source of protein extracts with inhibitory activity in vitro and in greenhouse plants; these findings were the foundation of this work, which focuses in the study of the enzymatic capacity of the proteins present in the protein extracts, due to their potential ability to degrade different compounds, including polysaccharides, lipids, peptides and nucleic acids, constituents of essential parts of a living cell; therefore these extracts can act as possible antifungal agents. In this study, protein extracts of G. lucidum obtained from bioreactor cultures (BIOFLO 110 ®) were characterized in terms of their deoxyribonuclease, ribonuclease, protease, glucanase and chitinase enzymatic activities. The extracts were also fractionated and each fraction obtained was evaluated for its inhibitory capacity against the phytopathogen fungus M. fijiensis, and through mass spectrometry analysis the presence of different enzymes with antifungal potential was confirmed.

Antifungal Susceptibility of Aspergillus flavus, Aspergillus ochraceus, and Fusarium graminearum to Ganoderma lucidum Extract

“…One of these effects is antimicrobial activity against viruses, bacteria, fungi, and yeasts. The possible sources of antifungal activity for G. lucidum have been attributed to proteins (27), lipopolysaccharides (11), organic acids (15), and glycoproteins (34). The results related to antifungal properties of different parts of G. lucidum are inconsistent, and this difference can be attributed to the method of extraction and the type of harmful fungal strains.…”

“…Also, several studies have shown the antifungal activity of G. lucidum against some harmful fungal species, including Aspergillusspp., Fusariumspp., Penicilliumspp. (15,(26)(27)(28)(29), and Candida albicans (30). Due to its significant properties, G. lucidum can be considered as a potential option for the production of new natural and healthy antifungal agents.…”

“…The high proportion of polyunsaturated fatty acids (17) and the diverse structure of bioactive polysaccharides contribute to the antimicrobial activity of G. lucidum (20). However, in a recent study, Arias-Londoño et al reported that potential antifungal protein extracts are also responsible for the antifungal activity of G. lucidum against the phytopathogen fungus Mycosphaerella fijiensis (27). Also, Wang and Ng described the antifungal activity of Ganodermin, an antifungal protein from fruiting bodies of G. lucidum (31).…”

Volumetric Oxygen Transfer Coefficient Effect on Biomass, Bioactive Compounds Production, and Kinetic Behavior of G. lucidum in Submerged Culture Using a Complex Medium.

“…Previous studies have reported the presence of enzymes with protease, chitinase, and glucanase activities in the crude protein extract of G. lucidum. These enzymes were linked to cell wall degradation and growth inhibition of Pseudocercospora fijiensis, a phytopathogen fungus that causes Black Sigatoka disease in Musaceae crops [4,5]. The use of these biomolecules as biological control agents in plants could help reduce or replace the pesticide amount applied in agriculture uses, contributing to the reduction of the environmental impact provoked by chemical agents conventionally used in the countryside.…”

“…This study aims to evaluate the effect of oxygen supply in a stirred tank bioreactor, through the variation of KLa initial value, on Ganoderma lucidum growth, exopolysaccharides production, and crude protein extract obtention [5]. The behavior of the fungus culture is shown through the kinetics of growth and the uptake of nutrients in a stirred tank bioreactor, operating in discontinuous mode and using a low-cost complex culture medium.…”