Journal of Pure and Applied MicrobiologyVol. 11 No. 1

Partial Characterization of Keratinolytic Activity of Local Novel Bacteria Isolated from Feather Waste

Dwi Suryanto*, Hilda Walida, Siti Khadijah Nasution, Erman Munir

Department of Biology, Faculty of Mathematics and Natural Sciences, University of Sumatera Utara, Medan, 20115, Indonesia.

Received on 25 November 2016 and accepted on 17 January 2017



Three keratinolytic bacterial isolates were characterized partially for their keratinase activity. Bacterial isolates were grown in feather meal agar. Ammonium sulfate precipitation followed by dialysis was performed to know the bacterial isolate keratinase activity in differet pH and temperature. Identification of the bacteria was done by using their 16S rRNA gene sequences. The result showed that bacterial growth was coinciding with keratinase activity. Precipitation with ammonium sulfate showed that keratinae activity of isolate A4 was optimum at 20% of ammonium sulphate, while B4 and B6 were more active at 70%. Keratinase activity increased after dialysis. Keratinase of A4 showed to have optimum activity at temperature of 45oC and pH=8, B4 was optimum at temperature of 35oC and pH=7, while B6 was optimum at temperature of 40oC and pH=7, respectively. Identification of the bacterial isolates using 16S rRNA gen showed that A4, B4, and B6 were closed to Leclercia adecarboxylata strain M-X17B, Azotobacter chroococcum strain ABA-1, and Stenotrophomonas maltophilia strain BIW by 97%, 99%, and 98%, respectively. Two bacteria L. adecarboxylata and A. chroococcum were firstly reported to produce keratinase.

Keywords : Keratinase, Chikhen feather, Goat fur, Azotobacter chroococcum, Leclercia adecarboxylata, Stenotrophomonas maltophilia.