An extracellular alkali-halotolerant cellulase from the strain Bacillus flexus NT isolated from Ulva lactuca was purified to homogeneity with a recovery of 25.03% and purity fold of 22.31. The molecular weight of the enzyme was about 97 kDa and the Vmax and Km was 370.17 U/ml/min and 6.18 mg/ml respectively. The optimum pH and temperature for enzyme activity was 10 and 45 °C respectively. The enzymatic hydrolysis of the CMC was confirmed with GPC and GC-MS analysis. The stabilized activity of the enzyme even at high pH of 9.0-12.0 and residual activity of about 70% at salt concentration (NaCl 15%) revealed for its alkali-halotolerance nature. The metal ions Cd 2+ and Li1+ were found as inducers while Cr2+, Co2+, Zn2+ and metal chelator EDTA have significantly inhibited the enzyme activity. Enzyme activity was insensitive to ethanol and isopropanol while partially inhibited by acetone, cyclohexane and benzene.
Bibliographical noteFunding Information:
The financial support received from CSIR (RSP 0016), New Delhi is gratefully acknowledged. We would also like to thank Dr. P. Paul, Head Analytical section for GPC, GC and SEM analysis reported in the present study. Mr. Manoj Kumar and Miss. Puja Kumari gratefully acknowledge the CSIR for awarding the Senior and Junior Research Fellowships respectively.
- Halo-alkali tolerance
- Marine habitat