초록
<P>Two aerobic bacterial consortia namely Con T and Con R were developed by enrichment technique from termite gut and cow dung respectively, using xylan as a sole carbon source. Molecular characterization of Con R based on 16S rRNA sequence analysis showed the presence of <I>Pannonibacter</I> sp. R‐3 and <I>Pseudoxanthomas</I> sp. R‐5. On the other hand, Con T showed the presence of <I>Pseudoxanthomas</I> sp. T‐5, <I>Cellulosimicrobium</I> sp. T‐21, and <I>Gordonia</I> sp. T‐30. Being the maximum xylanase producer among the five isolates and being a novel xylanase producing bacterial genus, <I>Gordonia</I> sp. T‐30 was selected. Xylanase produced by <I>Gordonia</I> sp. T‐30 showed optimum activity at 60 °C and pH 9. Xylanase was 95% stable for 120 min at pH 9.0 and 98% stable at 60 °C for 90 min. Xylanase activity was stimulated in the presence of organic solvents such as petroleum ether, acetone, diethyl ether, n‐hexane, and benzene. Detergent like cetyltrimethylammonium bromide and presence of NaCl also accelerated the xylanase function. Comparative evaluation was studied between sterilized and non‐sterilized solid fermentation to produce xylanase by <I>Gordonia sp</I>. T‐30 using various agricultural residues as growth substrate in cost effective manner. Industrially important features endowed by this xylanase make it a very promising candidate for food, feed, and fuel industry.</P>