Screening, Characterization and Identification of Cellulase Positive Bacillus Spp. Isolated From Pond Sediment Samples

Abstract

In the present investigation attempts have been made to isolate, identify and characterize the cellulase positive
Bacillus species isolated from pond sediment samples. Out of 20 collected samples based on heat treatment
survival and carboxymethyl cellulose interaction assay, 16 isolates were confirmed as Bacillus spp. owing
cellulase activity. All the isolates were observed as Gram positive, endospore producing rod shaped aerobic
bacteria in microscopic examination. Biochemical characterization of the isolates showed all the isolates to be
positive for catalase, urease and oxidase activity, negative for indole and H2S production, and variation in
methyl red, Voges Proskauer, citrate and nitrate activity was observed. Carbohydrate utilization tests revealed
all of the isolates to be positive for glucose, fructose, trehalose and cellobiose while most all strains were
negative for melezitose, rhamnose and mellibiose. Extracellular enzyme activity production for caseinase and
gelatinase was found be positive for all the isolates whereas variation in amylase, lecithinase and negative for
lipase activity was observed with all the isolates. Physiological responses in relation to salt and temperature was
found to tolerate maximum 7% of NaCl concentration and a temperature range of 60? for most of the isolates.
All the isolates were identified as different strains of 3 major groups of B. subtilis (08), B. pumilis (02) and B.
cereus (06). This study reveals that Bacillus spp. to be the dominant cellulase producers in pond sediment
samples and can be employed in industrial production of cellulose degrading enzymes.In the present investigation attempts have been made to isolate, identify and characterize the cellulase positive
Bacillus species isolated from pond sediment samples. Out of 20 collected samples based on heat treatment
survival and carboxymethyl cellulose interaction assay, 16 isolates were confirmed as Bacillus spp. owing
cellulase activity. All the isolates were observed as Gram positive, endospore producing rod shaped aerobic
bacteria in microscopic examination. Biochemical characterization of the isolates showed all the isolates to be
positive for catalase, urease and oxidase activity, negative for indole and H2S production, and variation in
methyl red, Voges Proskauer, citrate and nitrate activity was observed. Carbohydrate utilization tests revealed
all of the isolates to be positive for glucose, fructose, trehalose and cellobiose while most all strains were
negative for melezitose, rhamnose and mellibiose. Extracellular enzyme activity production for caseinase and
gelatinase was found be positive for all the isolates whereas variation in amylase, lecithinase and negative for
lipase activity was observed with all the isolates. Physiological responses in relation to salt and temperature was
found to tolerate maximum 7% of NaCl concentration and a temperature range of 60? for most of the isolates.
All the isolates were identified as different strains of 3 major groups of B. subtilis (08), B. pumilis (02) and B.
cereus (06). This study reveals that Bacillus spp. to be the dominant cellulase producers in pond sediment
samples and can be employed in industrial production of cellulose degrading enzymes.