Production,characterization and applications of cellulase from thermophilic Anoxybacillus and Bacillus

Abstract

Abstract Organic biomass is rich in cellulose and it is the most abundant substrate for biofuel production. To address the challenges posed by cellulosic biomass, cellulolytic microorganisms help improve the feasibility of biofuel production from cellulosic biomass. Present research was aimed to assess the cellulase production and activity of thermophilic isolates discovered from Tata Pani hot spring, Kotli AJ&K. Four thermophilic bacteria were screened for thermostable cellulase production on the basis of clear zone formation with 1 % CMC. Selected strains were Anoxybacillus mongoliensis (MBT001), Anoxybacillus flavithermus (MBT002), Bacillus spp. (MB004) and MBT003 (Anoxybacillus mongoliensis and Anoxybacillus flavithermus). Enzyme production and activity was assayed by DNS method. Optimum catalyst formation was observed and validated by RSM at 70 °C, 7 pH and 1.25 % substrate concentration with inocula size of 300 µL after 48 hrs of incubation. All the isolates gave maximum activity in presence of CMC upto range of 4.1-4.9 U/mL. Optimum enzyme activity of crude and purified enzyme was obtained upto range of 3-4 U/mL at pH 7. Crude and purified enzyme was stable upto 70 °C of temperature. Stability of cellulase from selected isolates was varied with surfactants and commercially available detergents being more stable with tween 20 and with commercially available Surf Excel. Cellulase from all isolates exhibited enzymatic hydrolysis of pre-treated banana peels. Crude cellulase from some isolates showed antimicrobial activity against Enterobacter and Pseudomonas. This study has showed that thermophilic bacteria are potential source of thermostable cellulase which can be highly used for many biotechnological purposes.