2.9.19
DETECTION OF SOME EXTRACELLULAR ENZYMES IN ENDOPHYTES

SK URS1, HS SHETTY1 and L LANGE2

lDepartment of Studies in Applied Botany, University of Mysore, Manasagangotri, Mysore 570 006, India; 2Novo Nordisk, Novo Alle 2880, Bagsvaerd, Denmark

Background and objectives
Endophytic fungi are represented in almost all groups of plants. Their establishment and subsequent colonization in the host plants necessitates the production and release of several enzymes and secondary metabolites. The actual ecological role of these endophytes is still not understood, although their cytotoxicidal and insecticidal properties have been well documented. In this study, some of the extracellular enzymes produced by selected strains of fungi isolated from plant tissues were detected using simple, qualitative plate assay methods.

Materials and methods
From a total of 250 plants (root and stem specimens), 60 fungal strains were isolated. The plants with fungal association belonged to 37 genera and 49 species. The fungi isolated were maintained as separate strains as identification was restricted. The strains were tested for their ability to produce extracellular cellulases, proteases and lipases on detection plates. The 20 strains selected were screened further for other associated cell wall degrading enzymes.

Results and conclusions
The results revealed protease, cellulase and lipase activity in majority of the strains. Xylanases and -glucanase activity were also detected in selected strains. Earlier investigations suggest that such enzymes play a role in fungal pathogenicity. The results lead us to speculate on the role of the endophytes and their enzymes in the plant tissues, although the interaction has been considered mutualistic.