Isolation and Identification of Cellulase-Producing Thermophilic Bacteria from Oil Palm (Elaeis guineensis)

Abstract

Cellulase is an enzyme catalyzing hydrolysis of cellulose which usually consists of endoglucanases (EC.3.2.1.4), exoglucanases (EC.3.2.1.91) and β-glucosidases (EC.3.2.1.21). Cellulase is a very important enzyme due to its numerous industrial applications. The aim of this research were to isolate and identify cellulase-producing thermophilic bacteria that can be used to increase value added in oil palm industries. Samples of soil, empty fruit bunch compost and palm kernel meal were collected from oil palm plantation for obtained thermophilic bacteria. The samples were screened of cellulase-producing thermophilic bacteria by using a Congo Red method were made on carboxymethyl cellulose (CMC) agar plates. The bacterial cultures were incubated in a shaking incubator (140 rpm) at 50oC for 24 hours. The assay for the enzymatic activity was based on the release of glucose that was detected using 3,5-dinitrosalicylic acid (DNS). In this research, 19 isolates of bacteria were isolated. It was found that 11 isolates of bacteria showed positive results with clear zone around the cultures by using Congo Red method. The result showed that isolates for CK1, EM4 and CK3 possesed the highest enzyme activity of 13.56, 12.50 and 10.49 U mL-1 for cellulase was detected at pH 7, respectively. The results of strain identification based on 16S rRNA showed that strain CK1, EM4 and CK3 were identified as Bacillus subtilis.