Zambrano Pazmiño, Diego E., Rivera Fernández, Ruben D., Guzmán Cedeño, Ángel M., Rondón, Ana J., Laurencio Silva, Marta, and Pére Quintana, Manuel
The present study aimed to isolate and select bacteria with cellulolytic capacity, having future application as inoculum in the fibrous organic waste composting. Five sampling environments were considered: organic agriculture (AO), conventional agriculture (AQ), forest (BM); sugarcane area (RC) and compost piles (AC). For bacterial isolation the nutrient agar medium was used changing the carbon source by cellulose. The main selection criterion of the bacterial isolates was the growth on above medium and its positive reaction to congo red test, showing clear zones around the colonies. The 93 bacterial isolates obtained were subjected to Gram staining, catalase test, presence of endospores and aerobically growth; having 70 bacteria Bacillus spp. like characteristics. Their cellulolytic activities were determined and 30 bacteria produced hydrolysis halo. Eight of these bacterial isolates were selected according to the largest halo production (AO-19, AO-28, AO-29, AQ-2, BM-7, RC-2, RC-6, CR-18) and their growth at different pH (3, 5, 7, 9) and temperatures (50 and 70 °C) were evaluated. The bacteria AO-19 showed higher hydrolysis halo with 12,33 mm and growth stability at different pH and temperature levels, for which its growth dynamic and amylolytic and pectinolytic capacity was determined. According to results the bacteria AO-19 has potential to be used as inoculum in composting. [ABSTRACT FROM AUTHOR]