초록
<P><B>Abstract</B></P> <P>This paper reports the cellulase (FPase) production by newly isolated <I>Bacillus velezensis</I> ASN1 using waste office paper (WOP) as feedstock and optimization of production conditions through two level factorial design, steepest ascent/descent and second order response surface methodology (RSM). Various fermentation parameters, like chemical factors (potassium dihydrogen phosphate, potassium chloride, yeast extract, magnesium sulphate, sodium nitrate, Tween 80, and waste office paper), physical factors (temperature, pH and time) and biological factor (inoculum size) were examined using two level full factorial design to check the key factors significantly affecting the cellulase production. The central composite design (CCD) was used to optimize the vital fermentation parameters, such as carbon (WOP), nitrogen, pH, and inoculum concentration in the medium for achieving higher cellulase production. The optimum medium composition was found to be WOP (9 g/L), sodium nitrate (0.35 g/L), inoculum size (6.56%) and pH 4.72. The model prediction of 2.46 U/mL cellulase activity at optimum conditions was verified experimentally as 2.42 U/mL.</P> <P><B>Highlights</B></P> <P> <UL> <LI> First report on cellulase production by <I>Bacillus velezensis</I> using waste paper. </LI> <LI> Pretreatment increased the cellulose content without any inhibitors formation. </LI> <LI> Central composite design increased the cellulase production by three fold. </LI> <LI> Cost-effective approach of waste management is achieved. </LI> </UL> </P>