Date Received: 07-02-2025 / Date Published: 20-02-2025
Cellulose-degrading bacteria play an increasingly important role in the ecosystem based on their extracellular enzyme activity, which is used for treatment of plant waste. This study aimed to identify the bacteria species in the gut of earthworms that are capable of decomposing cellulose, so that bacteria can be applied to decompose agricultural by-products. 30 bacterial strains were isolated from the gut of earthworms with colony morphology mainly white, round, rod shaped cells, gram positive and hads the ability to move. Cellulolytic activity was qualified by agar well diffusion method. The results showed that 53,33% of bacterial strains were capable of degrading CMC (carboxymethyl cellulose) with the degrading ring diameter in the range of 2,67-24,67mm, bacterial strain with the strongest ability to degrade CMC was NT20 (24,67 ± 1,15mm). Bacterial cellulase activity was determined by DNS method. The result showed that bacterial strain NT20 had the ability to produce the highest reducing sugar content (50,70 ± 1,01 µg/ml) compared to the remaining bacterial strains after 48 hours of culture. NT20 bacteria had the ability to decompose 51,33% of green vegetable by-products within 10 days. The 16S rRNA gene sequence of bacterial strain NT20 was 100% similar to Bacillus amyloliquefaciens strain HT-22-B1.
