Isolation and characterization of Soil Termites (Macrotermes gilvus) cellulolytic bacteria and activity determination of cellulase enzyme on newsprint substrates

Abstract

The study aims to explore and identify cellulolytic bacteria of termites that have the potential to cellulose hydrolysis on newsprint into glucose. The cellulolytic bacteria are characterized by the formation of clear zones in the medium agar containing newsprint paper after 0.1% Congo red testing. The isolates that produce large clear zones are identified by the type of bacteria. Identification of bacteria morphologically in colonies, gram staining and biochemical tests. The activity of cellulose enzyme based on concentration of reducing sugar (glucose) produced from the cellulose hydrolysis on newsprint was tested by 3.5-dinitrosylicyl reagent using a UV-Vis spectrophotometer. The results showed that 6 cellulolytic bacterial isolates through the Congo red test, 2 isolates that have a large diameter of the clear zone are: Isolates C1 and D1 4.27 cm and 2.05 cm, respectively. Cellulase enzyme crudes of isolates C1 and D1 have an enzyme activity of 15.7 mU/mL and 2.33 mU/mL, protein concentration of 0.35 mg/mL and 1.18 mg/mL with specific activity of 45.17 mU/mg protein and 1.98 mU/mg protein. Based on the observation of the colony's morphology in macroscopy, microscopy and biochemical test results, an isolate of C1 is the Provedencia sp and D1 isolate is the Bacillus sp.