<span style="font-size:11.0pt;font-family: "Times New Roman";mso-fareast-font-family:"Times New Roman";mso-bidi-font-family: Mangal;mso-ansi-language:EN-GB;mso-fareast-language:EN-US;mso-bidi-language: HI" lang="EN-GB">Bioreduction of Cr (VI) by Biosurfactant Producing Marine Bacterium <i style="mso-bidi-font-style:normal">Bacillus subtilis</i> SHB 13</span>

Abstract

<span style="font-size:11.0pt;font-family: " times="" new="" roman";mso-fareast-font-family:"times="" roman";mso-bidi-font-family:="" mangal;mso-ansi-language:en-gb;mso-fareast-language:en-us;mso-bidi-language:="" hi"="" lang="EN-GB">Heavy metal tolerant <i style="mso-bidi-font-style:normal">Bacillus subtilis </i>SHB 13 was isolated from marine source and characterised for biosurfactant activity. Selected strain SHB 13 was able to tolerate 800 ppm nickel (Ni), 1000 ppm chromium (Cr), 3000 ppm lead (Pb). Biosurfactant produced by this strain was surfactin, as characterized by FT-IR spectrum and further confirmed by molecular characterization and gene length was found to be 675 base pairs. <i style="mso-bidi-font-style:normal">B. subtilis </i>SHB<i style="mso-bidi-font-style:normal"> </i>13 was able to reduce 98% of 100 ppm Cr within 72h at optimized conditions of pH 7, temperature 37°C and 4% NaCl concentration. Surfactin (10mg/ml) produced by SHB 13 was efficient in removing 74 % Cr (VI) within 72h when analysed with AAS and its role in chelation was elucidated by FTIR, XRD and SEM equipped with EDS.</span>