Metabolic profiling analysis of the vitamin B₁₂ producer Propionibacterium freudenreichii

Abstract

Vitamin B 12 (VB 12 ) is an indispensable cofactor of metabolic enzymes and has been widely used in the food and pharmaceutical industries. In this study, the effects of medium composition on VB 12 production by Propionibacterium freudenreichii were evaluated and optimized based on statistical experiments. The results showed that glucose, yeast extract, KH 2 PO 4 , and glycine have significant effects on VB 12 production. The final titer of VB 12 reached 8.32 ± 0.02 mg/L, representing a 120% increase over the non‐optimized culture medium. We employed a metabolomics approach to analyze the differences of metabolite concentrations in P . freudenreichii cells cultivated in the original medium and optimized fermentation medium. Using multivariate data analysis, we identified a range of correlated metabolites, illustrating how metabolomics can be used to explain VB 12 production changes by corresponding differences in the overall cellular metabolism. The concentrations of many metabolic intermediates of glycolysis, the Wood–Werkman cycle, the TCA cycle, and amino acid metabolism were increased, which contributed to the synthesis of propionic acid and VB 12 due to an improved supply of energy and precursors.

Developing a single-stage continuous process strategy for vitamin B12 production with Propionibacterium freudenreichii

“…These results suggested that the growth and production of our strain were limited not only by the lack of carbon source but also by other factors such as propionic acid inhibition. The latter effect has been widely reported previously [32] and propionic concentration in the final stages of the cultures was probably too high for our strain, around 18 g/L in the batch processes. Considering this inhibition, a fed-batch strategy without a mechanism for propionic acid elimination/ removal (for example, an expanded bed reactor like the one used in [34]) does not seem to be a viable strategy for cobalamin production.…”

“…Other P. freudenreichii wild-type strains presented similar values compared to our static condition in terms of CNCbl volumetric production. For example, Liu et al reported productions with their non-optimized media of around 3.81 mg/L [32] and Chamlagain and coworkers reported a production of 5.3 mg/L in whey-based media [23].…”

“…To increase market accessibility, all the improvements performed were done at a bioprocess level, without any genetic modification. Besides, industrial cheap media were preferred such as corn steep liquor (CSL), a byproduct of the mill industry, over more expensive alternatives like yeast extract (YE), even though the combination of both CSL and YE has recently been reported to have a positive effect on cobalamin production [32].…”

Microbial Secondary Metabolites via Fermentation Approaches for Dietary Supplementation Formulations

“…However, the prices for the vitamins produced are significantly higher [96,97]. Vitamin extraction from microorganisms involves different processes [96][97][98][99][100][101][102][103][104][105][106][107]:…”

“…However, the prices for the vitamins produced are significantly higher [ 96 , 97 ]. Vitamin extraction from microorganisms involves different processes [ 96 , 97 , 98 , 99 , 100 , 101 , 102 , 103 , 104 , 105 , 106 , 107 ]: Cell disruption: Break open the bacterial cells to release the intracellular contents, including the vitamin. Cell disruption methods can include mechanical disruption (e.g., bead milling, high-pressure homogenization) or enzymatic treatments.…”