A Local Isolate of Non-Cellulolytic, Xylanolytic,
and Pectinolytic Thermophilic Fungus
Thermomyces lanuginosus Cla
Twenty strains of thermophilic fungi were screened for their production of xylanolytic and cellulolytic enzymes in liquid medium containing birchwood xylan as substrate. All strains were found to be xylanolytic but only 3 strains were proven to be non-cellulolytic. One of the strain C1a was finally selected based on the highest xylanase production and absence of cellulolytic activity in culture filtrates. The selected thermophilic fungus, identified as a strain of Thermomyces lanuginosus has optimum temperature and pH for growth at 55°C and pH 6.0, respectively. It grew well on both Potato Dextrose Agar and Mandels & Sternberg medium in which cellulose was substituted with xylan. Among various cellulosic, sugars and xylan-based substrates as carbon sources, xylan and corn cob induced simultaneous production of high levels of xylanase and pectinase. Maximum enzyme activities of 5,846 and 840 IU/mL xylanase and pectinase, respectively, were obtained in liquid Mandels and Reese medium with 3% corn cob at pH 6.0 after 7 d incubation at 50°C and 150 rpm.
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