title: Optimization, purification and characterization of novel thermostable, haloalkaline, solvent stable protease from Bacillus halodurans CAS6 using marine shellfish wastes: a potential additive for detergent and antioxidant synthesis.
abstract: A protease producing marine bacterium, Bacillus halodurans CAS6 isolated from marine sediments, was found to produce higher enzyme by utilizing shrimp shell powder. Optimum culture conditions for protease production were 50 °C, pH 9.0, 30 % NaCl and 1 % shrimp shell powder (SSP) and the protease purified with a specific activity of 509.84 U/mg. The enzyme retained 100 % of its original activity even at 70 °C, pH 10.0 and 30 % NaCl for 1 h. The purified protease exhibited higher stability when treated with ionic, non-ionic (72-94 %) and commercial detergents (76-88 %), and organic solvents (88-126 %). Significant blood stain removal activity was found with the enzyme in washing experiments. The culture supernatant supplemented with 1 % SSP showed 93.67 ± 2.52 % scavenging activity and FT-IR analysis of the reaction mixture confirmed the presence of antioxidants such as cyclohexane and cyclic depsipeptide with aliphatic amino groups. These remarkable qualities found with this enzyme produced by Bacillus halodurans CAS6 could make this as an ideal candidate to develop the industrial process for bioconversion of marine wastes and antioxidant synthesis.
authors.affiliation: Department of Chemistry, University of Puerto Rico at Cayey, 205 Ave. Antonio R. Barcelo, Cayey, PR 00736. annabact@gmail.com
authors.forename: Neelamegam
authors.initials: N
authors.lastname: Annamalai
authors.forename: Mayavan Veeramuthu
authors.initials: MV
authors.lastname: Rajeswari
authors.forename: Rengathavasi
authors.initials: R
authors.lastname: Thavasi
authors.forename: Shanmugam
authors.initials: S
authors.lastname: Vijayalakshmi
authors.forename: Thangavel
authors.initials: T
authors.lastname: Balasubramanian
mesh_terms: D000468:Alkalies / Q000378:metabolism*; D000975:Antioxidants / Q000138:chemical synthesis*; D001407:Bacillus / Q000201:enzymology*; D001483:Base Sequence; D017931:DNA Primers; D003902:Detergents / Q000737:chemistry*; D004795:Enzyme Stability; D005285:Fermentation; D006863:Hydrogen-Ion Concentration; D008386:Marine Biology; D010447:Peptide Hydrolases / Q000378:metabolism*; D012758:Shellfish; D012965:Sodium Chloride / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D000468:Alkalies; D000975:Antioxidants; D017931:DNA Primers; D003902:Detergents; D012965:Sodium Chloride; D010447:Peptide Hydrolases