Four strains of anaerobic gut fungi isolated from different geographical areas were grown at 1, 2, 4, and 6 days on rice straw substrate for comparison of fermentation end-products, substrate utilization and secretion of cellulose and xylanase enzymes. Two of the fungi (Piromyces rhizinflata B157 and Orpinomyces joyonii SG4) were isolated from the fences of bison in England and the rumen of sheep in Canada, respectively, and the other two fungi(Piromyces SS23-2 and Orpinomyces KNGF-2) isolated from the rumen of sheep and Korean native goat, respectively in Korea.
The rice straw degradation rate by tested anaerobic gut fungi after 6 days of incubation were estimated 50.54, 31.19 and 58.82 and 53.03% for P. rhizinflata B157, O. joyonii SG4, Piromyces SS23-2 and Orpinomyces KNGF-2, respectively. Two of fungi belong to Piromyces genus secreted the more higher levels of enzymes in a relatively short time than those belong to Orpinomyces genus. Fungi isolated in Korean also secreted the more higher levels of CMCase and xylanase enzymes than those isolated in Canada and England, with statistical difference(P$lt;0.05).
Our results indicated that the cellulolysis by anaerobic gut fungi could be different according to the geographical distribution, host animals, isolation parts such as rumen, fences or saliva etc, even though classified and assigned same genus of fungi. The correlation of the diversity of gut fungi with their hosts and geographic areas, their physiology, especially their cellulolytic activities, and their origins and relationships with other organisms should all prove to be fruitful areas for future research.
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