Abstract

OPTIMIZATION OF PROTEASE PRODUCTION BY ENDOPHYTIC FUNGUS, ALTERNARIA ALTERNATA ISOLATED FROM GYMNOSPERM TREE- CUPRESSUS TORULOSA D.DON

Kavish Rajput, Sheetal Chanyal and Pavan Kumar Agrawal*

ABSTRACT

The term endophytes include a family of microorganisms that grow intra-and/or intercellularly in the tissues of higher plants without any symptoms on the plant in which they reside. Endophytic fungi exhibit a complex web of interactions with host plants and have been extensively studies over the last several years as prolific sources of natural products. Fungal enzymes were used in food, beverages, confectionaries, textiles and leather industries to simplify the processing of raw materials. There is a growing need for new enzymes, especially proteases, which is used in industry which can perform function under variety of conditions. They are often more stable than enzymes derived from other sources. Enzymes of the endophytes are degraders of the polysaccharides, lipid and proteins available in the host plants. The use of simpler solid media permits the rapid screening of large populations of fungi for the presence or absence of specific enzymes. In present investigation, a total ofeight different fungal endophytes such as Alternaria alternata, Aspergillus sp, Cladosporium sp, Curvularia sp, Diaporthe sp, Fusaium sp,. etc were isolated from Cupressus torulosa D.Don. Fungal endophytes were screened qualitatively for the production of extracellular enzymes such as amylases, cellulases, proteases, lipases andlaccases. Fifty percent of fungi endophytes screened for enzymes showed positive for protease, cellulase and amylase, Out of them 33% for laccase and none of isolates showed lipase activity. In this study fungal endophytes showed prominate protease activity. Among them isolates Alternaria alternata designated PCTS21 showed the greatest protease activity. Hence, Protease production of Alternaria alternata was optimized by assessing the effects of temperature, pH, carbon source and nitrogen source on activity. The broadest activity was observed between 25˚ and 50˚C at pH 7, suggesting a neutral protease. Overall, the optimum conditions were observed at 27°C and pH 7. The characteristics demonstrated by this fungal endophyte showed that it is a potential source of an enzyme with applications in the dairy industry. The strong enzymatic activities of the endophytic extracts show a high potential for clinical microbiology and therapeutic applications. The array of enzymes produced differs between fungi and often depends on the host and their ecological factors.

Keywords: Cupressus torulosa D. Don, Endophytic fungi, Alternaria alternata, Enzymatic activity, Protease production.