Anaerobik Gut Fungusları İle Laktik Asit Bakterilerinin Kokültür Olarak Yetiştirildiklerinde Enzim Aktiviteleri Üzerine Etkileri

Abstract

Rumen, main compartment of the stomach of ruminant herbivores, have a low redox potential and anaerobic ecosystem in where various microbial populations inhabit, such as bacteria, anaerobic gut fungi (AGF), protozoa and archaea. These microbial groups have a symbiotic life whilist both synergetic releationship and inhibition of some activities could be observed when they are cultured as mixture. Relatively higher enzyme activities of the AGF is well documented although our knowledge about the possible effects of coculturing with lactic acid bacteria on their enzyme activity is still limited. In current work, AGF Neocallimastix GMLF11 was cocultured with Enterecoccus sp and Bifidobacterium sp separately and its enzyme activities (inulinase and sucrase) were determined at 45 oC after 24, 36 and 48 hours incubation periods. The highest supernatant specific sucrase (EC 3.2.1.48) activity of Neocallimastix GMLF11 and Enterecoccus sp coculture was determined as 21,4 mol/min/mg/ml protein for 36h incubation while cell associated specific sucrase activity of same mixture was observed as 22,4 mol/min/mg/ml protein for 48 h incubation. Neocallimastix GMLF11 and Bifidobacterium sp coculture showed the highest cell associated specific sucrase activity at 48h incubation as 22,4 mol/min/mg/ml protein, whilst that activity was determined as 24,6 mol/min/mg/ml protein for supernatant samples at the end of 24h incubation period. The highest cell associated and supernatant specific activities of pure culture of Neocallimastix sp was 8 and 12,3 mol/min/mg/ml respectively. Axenic cultures of Enterecoccus sp and Bifidobacterium sp showed 20,7 and 21 mol/min/mg/ml protein supernatant enzyme activity respectively, while cell associated specific activities of that cultures were calculated as 15,9 and 17,6 mol/min/mg/ml protein respectively. These results suggest that enzyme activities of these microbial groups are remarkably induced when they were grown in coculture.