Determination of cellulase activity from cellulase producing bacteria by using agro-wastes as substrates / Nor Eilya Natasha Abd Halim

Microcrystalline cellulose (MCC) is an expensive commercial substrate that have high in demand in industries for screening of cellulase activity. In order to reduce the cost of screening procedure in industries for production of cellulase enzyme, the alternative substrates were used. The alternative subtrates that were used are Citrullus lanatus (watermelon), Psidium guajava (guava), Mangifera indica (mango), Cucumis sativus
(cucumber) and Trichosanthes cucumerina (snake gourd) have been used. This is because all of the alternative substrates consist of lignocellulosic composition that will be degraded by cellulase enzyme that are produced by Bacillus subtilis. The aim of this study are to measure the hydrolysis capacity of celullase activity on different concentrations of Citrullus lanatus (watermelon), Psidium guajava (guava), Mangifera
indica (mango), Cucumis sativus (cucumber) and Trichosanthes cucumerina (snake gourd) as substrates. The concentrations that were used in this research are 10 g/L, 20
g/L and 30 g/L respectively. Next, the adjustment of turbidity of bacterial suspension by standardizing to the I x I 08 CFU/mL. Thus, spot plate method were used to screen
the cellulase production. Spot plate method were used for limitation of growth so that the bacterial colonies will never grow all over the plate. As a result, the cellulase
enzyme that was produced from Bacillus subtilis gave positive results of cellulase activity on all of the agar medium containing MCC and alternative substrates. Thus, it can be concluded that all of the alternative substrates at IO g/L, 20 g/L and 30 g/L of concentrations can be potential cost effective substrates in industries.