EVALUATION OF THE CELLULOLYTIC ACTIVITY OF ENDOPHYTIC BACTERIA ISOLATED FROM Mikania glomerata

Enzymes are important biomolecules that have a strong impact on industrial sectors, such as food production, animal feed, brewing and wine making, biomass refining, paper, textile industry, laundry, among others. The enzymes are naturally found from animals to plants, and the most widely used are enzymes of microbial origin, being extremely diversified in their catalytic properties and specificity for the substrate presenting biotechnological potential, especially endophytes that inhabit interior plant tissues and organs without causing harm to their host. Endophytes are part of one of the diversity of unexplored fungi. Many of the studies carried out with endophytic fungi are based on diversity studies, while only a few studies report their practical biotechnological applications. There have been reports of cellulase, amylase, pectinase, xylanase and others production by endophytic fungi isolated from various plants. The present work aims to evaluate the cellulase production of ten strains of endophytic bacteria isolated from Mikania glomerata (“Guaco”). The strains MG108, MG105, MG56, MG26, MG37, MG58, MG60, MG13, MG17, MG86 were grown in TSB medium (Tryptic Soy Broth; pH 7.3) for 24 h at 28°C, after which they were adjusted in 0.85% saline with the aid of the McFarland Scale 0.5 (108 CFU.mL-1). The 2 μl aliquot of the resulting suspension was transferred to inducing medium (6 g NaNO3, KCO 5 g, KH2PO4 1.5 g, MgSO4.7H2O 0.5 g, ZnSO4 0.01 g, FeSO4 0.01 g, 10 g, 15 g agar, supplemented with 0.5% of yeast extract and 1% of CMC; distilled water 1000 mL - pH 6.4) at five points equidistant in the plate. The experiment was performed in triplicate and stored for 72h at 28 °C. Plates were developed with the aid of 0.1% Congo red dye for 30 min and subsequently washed with 5M NaCl solution for 15 min., Enzyme production was indicated by halo formation and diameters were measured in millimeters. After bacterial growth and development of the strains, only strain MG86 was highlighted for the enzymatic activity, presenting a colorless halo with a size of 3.66 mm, suggesting endoglucanase secretion. The other strains showed growth in the inducing medium, however, they did not present halo formation. Thus, the strains MG86 presented a promising future biotechnological application aimed at the enzymatic prospection, especially the cellulolytic activity.