Open AccessDirect Bio-Utilization of Untreated Rapeseed Meal for Effective Iturin A Production by Bacillus subtilis in Submerged Fermentation
Author(s) -
Jin Hu,
Zhang XinRan,
Kunpeng Li,
Yanxing Niu,
Ming Guo,
Chuanjiong Hu,
Xia Wan,
Yangmin Gong,
Fenghong Huang
Publication year - 2014
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0111171
Subject(s) - rapeseed , food science , bacillus subtilis , fermentation , glucosinolate , meal , chemistry , ammonium nitrate , biology , agronomy , brassica , bacteria , organic chemistry , genetics
The feasibility of using untreated rapeseed meal as a nitrogen source for iturin A production by Bacillus subtilis 3–10 in submerged fermentation was first evaluated by comparison with two different commercial nitrogen sources of peptone and ammonium nitrate. A significant promoting effect of rapeseed meal on iturin A production was observed and the maximum iturin A concentration of 0.60 g/L was reached at 70 h, which was 20% and 8.0 fold higher than that produced from peptone and ammonium nitrate media, respectively. It was shown that rapeseed meal had a positive induction effect on protease secretion, contributing to the release of soluble protein from low water solubility solid rapeseed meal for an effective supply of available nitrogen during fermentation. Moreover, compared to raw rapeseed meal, the remaining residue following fermentation could be used as a more suitable supplementary protein source for animal feed because of the great decrease of major anti-nutritional components including sinapine, glucosinolate and its degradation products of isothiocyanate and oxazolidine thione. The results obtained from this study demonstrate the potential of direct utilization of low cost rapeseed meal as a nitrogen source for commercial production of iturin A and other secondary metabolites by Bacillus subtilis .