Abstract
To increase the efficency of utilizing cellulosic biomass, a potent xylanase producing bacteria was isolated and identified as Bacillus sp. N-25. Extracellular xylanase from Bacillus sp. N-25 was partially purified by ammonium sulfate precipitation, DEAE-Sephadex A-25 and Sephadex G-IOO column chromatographies. The xylanase was single fraction on chromatography and was true xylanase without cellulase activity. The enzyme was stable at pH 6-8 and 80% activity was remained at $50^{\circ}C$ for 30 min, but was inhibited by $Hg^{2+}$, $Ag^{2+}$, and $Mn^{2+}$. From the fact that the major end product was xylose, we suggested that the enzyme is an exo-xylanase which may be a prime candidate for industrial use.
섬유소 자원의 효율적 이용을 위하여 강력한 xylan 분해효소 생산 세균을 분리 및 선발하였으며, 형태학적, 배양학적 생리학적 특성을 확인한 결과 Bacillus sp. N25로 동정하였다. 이 균주에 의해서 생산된 효소를 ammonium sulfate precipitation, DAEA-sephadex A-50, Sephadex G-100 column으로 부분 정제하여 얻은 효소의 열안정성은 $50^{\circ}C$에서 30분간 처리시 80 의 역가가 잔존 했으며, pH 안정은 pH 6-8 범위에서 30'C에서 10시간 방치 후에도 안정했으며, cellulose 분해능력은 없었으며, $Hg^{2+}$, $Ag^{2+}$, $Mn^{2+}$에 의해 저해되었다. 그리고 최종분해산물은 주로 xylose이므로 exo-type xylanase로 추정된다.
