ISOLATION AND ASSAY OF AMYLASE AND CELLULASE ACTIVITIES AT MESOPHILIC AND THERMOPHILIC PHASES IN MANURE COMPOSTING PROCESS

• Main Author: RUBIATY (NIM : 10508035); Pembimbing I : Fida Madayanti W., Ph.D; Pembimbing II : Dr. Ih, NADHILAH
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/16634
• Institution: Institut Teknologi Bandung

Composting is a decomposition of raw manure materials into simple organic materials that can be utilized by plants. The decomposition process involves microorganisms producing enzymes such as amylase and cellulase. In this study, microbes were isolated from compost; microbial amylase and cellulase were identified and their enzyme activity assays were performed to determine the optimum activity at both mesophilic and thermophilic phase of composting. Microbes from the compost were grown using Luria Bertani medium (LB) to produce single colonies that can be used as a collection of microbial compost. The amylase producing microbes were selected by growing the collection of microbial compost in agar medium containing starch substrate. Cellulase-producing microbes selected using agar medium containing substrate CMC (carboxymethyl cellulose). Results of this study indicate that the compost from the mesophilic phase has only an amylase activity, whereas samples from the thermophilic phase showed amylase activity and cellulase. Each of the two phases of enzymatic activity determined by the DNS (3,5-dinitrosalicylic acid) method. The highest amylase activity was possessed by B9 bacteria (1,086 (mu)mole mg-1minute-1). The highest cellulase activity was shown in bacteria B5 (14,985 nmole mg-1 minute-1). Fenotyping assay of both bacteria performed with the Gram stain test showed that bacteria B5 and B9 bacteria are rod-shaped Gram-positive bacteria. Genotyping assay was performed with 16S rDNA gene sequencing. The sequencing results were analyzed using the BLAST program (Basic Logical Alignment Search Tool). Bacteria B9 has 99% similarity with the Bacillus thermoamylovorans while B5 has 94% similarity with Bacillus fumarioli.