Comparison of different stains in determination of extracellular cellulose activity of Odontotermes obesus gut bacteria
Nidhi Kakkar, Sanjeev K Gupta, Baljeet Singh Saharan
Termites (Isoptera) are known to hydrolyse the polysaccharide: cellulose, hemicellulose and lignocellulose into glucose monomers with the help of symbiotic bacteria of their gut. Fifty termite (Odontotermes obesus) guts were extracted then homogenized to culture the bacteria on nutrient agar. Then the isolated bacterial colonies were cultured on CMC media at 370 C for 24 hrs. A total of 12 isolates grew on CMC but only 9 have shown cellulolytic activity. Out of 9, 4 were obtained from soldiers and 5 from workers. Then these colonies were isolated for cellulolytic activity. The potential of bacteria to degrade cellulose was measured with the help of different stains like Congo Red, Comassie Brilliant Blue R 250 stain, Safranin and Gram’s Iodine stain. The soldiers showed more cellulolytic activity than workers. On the basis of these staining techniques, it was found that the Gram’s Iodine is the best stain to measure the cellulolytic activity. So it forms significantly higher zone of clearance. Congo Red also showed poor stain retention with degraded polymer. Clear zone formation depends on binding of degraded polymer with stain and on bacterial isolate.