Abstract
BackgroundThe lipopeptide antibiotic iturin A is an attractive biopesticide with the potential to replace chemical-based pesticides for controlling plant pathogens. However, its industrial fermentation has not been realized due to the high production costs and low product concentrations. This study aims to enhance iturin A production by performing a novel fermentation process with effective glucose feeding control using rapeseed meal as a low-cost nitrogen source.ResultsWe demonstrated that continuous and significant enhancement of iturin A production could be achieved by a novel two-stage glucose-feeding strategy with a stepwise decrease in feeding rate. Using this strategy, the ratio of spores to total cells could be maintained at a desirable/stable level of 0.80–0.86, and the reducing sugar concentration could be controlled at a low level of 2–3 g/L so that optimal substrate balance could be maintained throughout the feeding phase. As a result, the maximum iturin A concentration reached 1.12 g/L, which was two-fold higher than that of batch culture.ConclusionsThis is the first report which uses control of the glucose supply to improve iturin A production by fed-batch fermentation and identifies some important factors necessary to realize industrial iturin A production. This approach may also enhance the production of other useful secondary metabolites by Bacillus subtilis.
Highlights
The lipopeptide antibiotic iturin A is an attractive biopesticide with the potential to replace chemicalbased pesticides for controlling plant pathogens
One of the most commonly used and well-studied microbial species, has the potential to produce more than two dozens of structurally diverse broad spectrum antimicrobial compounds with high viability [4]
Iturin A is a cyclic lipopeptide antibiotic consisting of a cyclic heptapeptide linked to a 14–17 carbons β-amino fatty-acid chain [5]
Summary
The lipopeptide antibiotic iturin A is an attractive biopesticide with the potential to replace chemicalbased pesticides for controlling plant pathogens. One of the most commonly used and well-studied microbial species, has the potential to produce more than two dozens of structurally diverse broad spectrum antimicrobial compounds with high viability [4]. Among these antimicrobial compounds, cyclic lipopeptides of the iturin, surfactin and fengycin families have. Iturin A is a cyclic lipopeptide antibiotic consisting of a cyclic heptapeptide linked to a 14–17 carbons β-amino fatty-acid chain [5] This special amphipathic structure endows iturin A with strong broad-spectrum antifungal activity so that it could be used as a potential biocontrol agent against harmful plant pathogens that cause crop diseases [6, 7]. Using low cost raw materials from abundant sources may be an important aspect to improve the economic viability of industrial
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.