title: Partial purification and some properties of alpha-amylase from Bacillus subtilis KIBGE-HAS.
abstract: An extracellular alpha-amylase from Bacillus subtilis KIBGE-HAS was partially purified by ultrafiltration and ammonium sulphate precipitation with 19.2-fold purification and specific activity of 4195 U/mg. The enzyme showed relatively high thermostability and retained 62% of its activity when kept at 70 degrees C for 15 min. alpha-Amylase was highly stable at -18 degrees C and loss of activity was very low during stability study. Metal ions like Mn2+ Ca2+, Co2+, K+, Mg2+, and Fe3+ activated the enzyme, while Hg2+ Ba2+, Cu2+, Na+ and Al3+ strongly inhibited the activity. The a-amylase was highly stable in various surfactants and detergents. In the presence of surfactants such as SDS and Triton X-100 the enzyme activity was found 2.9 and 1.8-fold higher respectively than control. The non-ionic detergents (Tween 20 and Tween 80) exhibited slightly inhibitory effect on the enzyme activity.
authors.affiliation: Pharmaceutical Research Centre, PCSIR Laboratories Complex, Karachi, Pakistan.
authors.forename: Saeeda
authors.initials: S
authors.lastname: Bano
authors.forename: Shah Ali
authors.initials: SA
authors.lastname: Ul Qader
authors.forename: Afsheen
authors.initials: A
authors.lastname: Aman
authors.forename: Abid
authors.initials: A
authors.lastname: Azhar
mesh_terms: D001412:Bacillus subtilis / Q000201:enzymology*; D008670:Metals / Q000494:pharmacology; D013501:Surface-Active Agents / Q000494:pharmacology; D013696:Temperature; D000516:alpha-Amylases / Q000302:isolation & purification* / Q000378:metabolism*
chemical_list: D008670:Metals; D013501:Surface-Active Agents; D000516:alpha-Amylases