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Improved propionic acid and 5,6-dimethylbenzimidazole control strategy for vitamin B12 fermentation by Propionibacterium freudenreichii

Paper ID Volume ID Publish Year Pages File Format Full-Text
22977 43408 2015 7 PDF Available
Title
Improved propionic acid and 5,6-dimethylbenzimidazole control strategy for vitamin B12 fermentation by Propionibacterium freudenreichii
Abstract

•Controlling propionic acid concentration could improve vitamin B12 biosynthesis.•Feed-back inhibition occurred in intermediate biosynthesis of vitamin B12.•Vitamin B12 biosynthesis increased upon the addition of DMB.•Propionic acid and DMB control strategy could improve vitamin B12 biosynthesis.•Vitamin B12 productivity of 0.59 mg/L/h was obtained by repeated batch fermentation.

An efficient fermentation-strengthening approach was developed to improve the anaerobic production of vitamin B12 by cultivation process optimization with Propionibacterium freudenreichii. The effects of the byproduct propionic acid and the precursor 5,6-dimethylbenzimidazole (DMB) on vitamin B12 biosynthesis were investigated. Byproduct inhibition experiments showed that maintaining propionic acid concentration in broth below 10–20 g/L in the early stage and 20–30 g/L in the late stage can efficiently improve vitamin B12 biosynthesis. Batch fermentation indicated the occurrence of feed-back inhibition in intracellular intermediate biosynthesis. In addition, the incorporation of the precursor DMB depended on the fermentation level of the vitamin B12 intermediate. High vitamin B12 concentration (58.8 mg/L) and production (0.37 mg/g) were obtained with an expanded bed adsorption bioreactor by using the propionic acid and DMB control method. The optimum concentration and production of 59.5 and 0.59 mg/L h for vitamin B12 production were respectively achieved after five continuous batches.

Keywords
Vitamin B12; Propionic acid; 5,6-Dimethylbenzimidazole; Feed-back inhibition; Expanded bed adsorption bioreactor
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Improved propionic acid and 5,6-dimethylbenzimidazole control strategy for vitamin B12 fermentation by Propionibacterium freudenreichii
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Publisher
Database: Elsevier - ScienceDirect
Journal: Journal of Biotechnology - Volume 193, 10 January 2015, Pages 123–129
Authors
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Subjects
Physical Sciences and Engineering Chemical Engineering Bioengineering
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us