Thermostable, salt-tolerant amylase fromBacillus sp. 64

Area of Science:

• Microbiology
• Enzymology
• Biotechnology

Background:

• Amylases are crucial industrial enzymes with diverse applications.
• Thermostable and salt-tolerant enzymes are highly sought after for challenging environments.
• Bacillus species are known producers of extracellular enzymes, including amylases.

Purpose of the Study:

• To characterize a novel amylase produced by Bacillus sp. 64.
• To evaluate the thermostability and salt tolerance of the enzyme.
• To determine optimal conditions for enzyme production and activity.

Main Methods:

• Cultivation of Bacillus sp. 64 under various conditions.
• Partial purification of the secreted amylase.
• Enzyme activity assays at different temperatures, pH, and NaCl concentrations.
• Optimization of carbon and nitrogen sources for enzyme production.

Main Results:

• Maximum amylase production of 8.0 U/ml was achieved after 24-h growth.
• The partially purified amylase remained stable at 60°C for 30 min.
• Significant activity (80%) was retained after incubation in 5M NaCl for 24 hours.
• Optimal enzyme production utilized starch/dextrin as carbon sources and peptone as a nitrogen source.
• The enzyme exhibited maximum activity between pH 7 and 8, with secretion over a wide pH range (5-11).
• Calcium (Ca2+) and Magnesium (Mg2+) ions stimulated both bacterial growth and amylase production.

Conclusions:

• Bacillus sp. 64 produces a thermostable and salt-tolerant amylase with potential industrial utility.
• The enzyme's broad pH activity and stability in high salt concentrations are advantageous.
• Optimized production conditions and the stimulatory effect of Ca2+ and Mg2+ offer avenues for further development.