Optimization of fermentation medium for cellulase produced by Bacillus subtilis BY-3 using response surface methodologyChinese Full Text

Meng Fanxu;Ma Li;Yang Weiping;Ji Shengyue;Xin Haiyun;Cao Binyun;

Abstract: In order to enhance yield and reduce production cost in cellulase fermentation industry, re-sponse surface methodology（RSM） was employed to optimize a medium for production of cellulase bythermophilic Bacillus subtilis BY-3. The single-factor design was initially used to screen the optimalcarbon source and nitrogen source, respectively, from agro-industrial cellulosic residuals and by-prod-ucts. Subsequently, a two factorial Plackett-Burman design was employed to identify the critical vari-ables for cellulase production, followed by the steepest ascent experiment for approaching the optimalresponse region rapidly and a five-level two-factor central composite design（CCD） for determining op-timum levels of critical variables.As a result, corn stover and soybean meal were screened as the opti-mal carbon source and nitrogen source, respectively. NaCl（X3） and corn stover（X6） were identified asthe critical variables for cellulase production and the optimized medium composition: MgSO4·7H2O0.3 g/l, K2HPO4·3H2O 1.5 g/l, NaCl 5.772 g/l, yeast extract 0.5 g/l, soybean meal 20 g/l, corn stover28.499 g/l, CaCl2·2H2O 0.1 g/l and Tween 80 0.1%（v/v）, for maximum cellulase production by B. sub-tilis BY-3 was obtained by RSM. Under the optimal medium, an over all 3.15-fold increase in cellu-lase yield with an average maximum carboxymethyl cellulase（CMCase） activity of（5.305±0.073）U/ml was achieved in shake flasks after 24 h sub-merged fermentation, which showed good agree-ment with the predicted response（5.263 U/ml） byRSM. This study will provide a potential solutionto utilize straws and develop cellulase preparation.

Keywords：

Bacillus subtilis; cellulase; corn stover; medium optimization; response surface methodology;

DOI：
10.13302/j.cnki.fi.2014.10.010
Series：
Subject：
Classification Code：
TQ925

Mobile Reading

Read on your phone instantly

Step 1
Scan QR Codes

"Mobile CNKI-CNKI Express" App

Step 2
Open“CNKI Express”

and click the scan icon in the upper left corner of the homepage.

Step 3
Scan QR Codes

Read this article on your phone.
HTML
CAJ Download
PDF Download

Contents

Optimization of fermentation medium for cellulase produced by Bacillus subtilis BY-3 using response surface methodologyChinese Full Text

Meng Fanxu;Ma Li;Yang Weiping;Ji Shengyue;Xin Haiyun;Cao Binyun;

Read on your phone instantly

Citation Network

Related Literature