Antifungal Activity and Properties of Crude Enzymes Produced from Cellulomonas fimi JH-1

Abstract

In this study, bacteria were isolated from rosemary rhizosphere and chitinolytic activity was detected in 0.2% chitin agar medium. Using 16s rRNA sequencing, the isolated bacteria were identified as Cellulomonas fimi. Chitinase, cellulase, and protease activities were found to increase with incubation time. Chitosanase activity was highest on day 1, and gradually declined thereafter. Crude enzyme of C. fimi was prepared and separated by SDS-PAGE and the expression patterns of enzyme activity for chitinase and chitosanase isozymes was studied. Three chitinase isozymes (36, 55, and 66 kDa) and one chitosanase (39 kDa) were detected SDS-PAGE gel combinded with glycol chitin and glycol chitosan, and these chitinase and chitosanase had different molecular weights. Indole acetic acid (IAA) production by C. fimi was analyzed in nutrient broth (NB) media containing different concentrations of tryptophan. IAA production was found to increase with increasing tryptophan concentration. Siderophore production by C. fimi was analyzed in colloidal chitin medium for 0, 1, 3, 5, and 7 d. The production of siderophore increased for 5 d and gradually decreased thereafter. The antifungal activities of C. fimi against G. zeae, F. solani, B. cinerea, F. oxysporum, C. cucumerinum, R. solani, and C. acutatum were investigated in potato dextrose broth medium containing chitin. C. fimi showed the highest antifungal activity against G. zeae.