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Showing 3 results for Vitamin B12
M Moosavi-Nasab , S Alasvand-Zarasvand , Ar Yousefi , Volume 5, Issue 4 (1-2011)
Abstract
Background and Objectives: Chemical production of vitamin B12 is a complicated process. The purpose of this study, done for the first time in Iran, was to produce vitamin B12 by Propionibacterium freudenreichii and investigate the effect of adding betaine on its yield.
Materials and Methods: Propionibacterium freudenreichii was added to a fermention culture medium containing filtrated soaked corn. This was followed by incubation at 30°C and, then, adding betaine at six concentrations (0, 5, 10, 15, 20 and 30 g/l). Separation and purification were done and the presence and the amount of vitamin B12 produced were determined by HPLC.
Results: The most effective concentration of betaine for vitamin B12 production (318.33 Pg/ml) was 10 g/l, which had a negative effect on dry weight of the cells (22.37 g/l). The results demonstrated that betaine could greatly stimulate vitamin B12 biosynthesis by Propionibacterium freudenreichii and inhibit cell growth.
Conclusion: Based on the findings of this study, betaine added to the culture medium of Propionibacterium freudenreichii at a suitable concentration could increase the yield of vitamin B12, paving the way to a commercial, more economic method for its production.
Keywords: Betaine, Fermentation, Propionibacterium freudenreichii, Vitamin B12
M Rezaei , N Kalantari , N Omidvar , Ar Abadi , M Hedayati , M Sabetkasaei , Volume 5, Issue 4 (1-2011)
Abstract
Background and Objectives: A deficiency of folate or vitamin B12, particularly in tissues with a high cell replication rate, could inhibit RNA and DNA synthesis, DNA methylation, as well as cell maturation. Therefore, a sufficient intake of these vitamins in childhood is of vital importance. Since there are no published reports on the status of folic acid and vitamin B12 in Iranian children, the present study was conducted to assess serum and red blood cells concentrations and some related factors in healthy 3-6 year-old children in Tehran, Iran, 2010.
Subject and Methods: This was a cross-sectional, descriptive-analytical study, in which 228 children, 3-6 year old (105 girls and 123 boys), were selected by random systematic cluster sampling from 20 (out of 270) day-care centers in Tehran. A 2-ml non-fasting blood sample was drawn from each child and analyzed for serum and red blood cell folate and vitaminB12 by the RIA method. SPSS.16 was used for data analysis, the statistical tests being t-test, Chi-square and ANOVA.
Results: There were no significant differences between the 2 sexes with regard to age, weight, height, BMI, RBC folate, or serum folate and vitamin B12 levels. Based on the serum folate level, 9.6% and 37.8% of the children suffered from severe and mild deficiency, respectively 52.6% had normal folate serum levels. The data also showed that 97.4% of the children had a normal serum vitamin B12 level, only 2.6% being mildly deficient. As judged by the RBC folate level, of 105 children (60 boys and 45 girls), 1% and 37% had severe and mild deficiency, respectively, an absolute majority (62%) having normal levels. The distributions of serum folate, serum vitaminB12, and RBC folate levels were not statistically different between boys and girls. Similarly, no associations were observed between the RBC folate level, serum folate level, or serum vitamin B12 level and age, weight, height, family size, birth order, or head of the family. There were positive significant correlations between serum folate on the one hand and RBC folate (r=0.4 , p<0.001) and serum vitamin B12 (r=0.8 , p<0.001) on the other hand. Furthermore, folate, RBC folate, and serum vitamin B12 were all positively related to father’s education (p=0.01), mother's education (p=0.008) and father’s job status (p<0.027). In addition, the vitamin levels were higher in children of the working mothers, as compared to those of non-working mothers (p<0.036). There were no differences between the 2 groups with regard to other variables.
Conclusion: Folate deficiency is highly prevalent, while the deficiency of vitamin B12 is low, among Tehrani preschoolers. It is recommended to design and implement suitable intervention programs. Major components of such programs should be mothers’ nutrition education and improving family food consumption patterns with particular emphasis on optimum utilization of folate sources, particularly vegetables.
Keywords: Folic acid, Vitamin B12, Preschoolers
S Zarean Shahraki , N Ahmadi , K Khosravi-Darani , Am Mortazavian , P Koohi-Kamali , Volume 10, Issue 2 (6-2015)
Abstract
Background and Objectives: Propionibacterium is capable of producing important industrial products such as propionic acid, vitamin B12 and bacteriocin. They have also probiotic benefits and growth factors for the intestinal useful bacteria. The goal of this research was evaluation of the influence of process variables on vitamin B12 production in fed-batch fermentation of a dairy beverage containing propionic acid by Propionibacterium freudenreichii ssp. shermanii.
Materials and Methods: Fermentation was conducted in a 3-L fermentor containing base medium and molasses as the carbon source to which the feeding was added after 36 hours. Sampling was done for biomass and vitamin measurements in 24 h intervals. The content of dry biomass and vitamin B12 was measured by freeze drying method and HPLC, respectively.
Results: Statistical analysis of the results showed that all process variables had significant effect on the response of the system (P<0.05). The final concentration of vitamin B12 (30 mg/L) and productivity (7.5 mg/L.h) was obtained from Treatment 9 while the condition of this treatment was the best. In this research, inocula and their volume as well as feeding had no significant impact on the productivity of vitamin B12 fermentation (P>0.05). Type of nitrogen source and feeding strategy were the most significant factors in this research, so using corn steep liquor and lactose significantly increased vitamin B12 production.
Conclusion: The best conditions for vitamin B12 production include: 30 °C, pH=6.5, 25 g/L molasses, 10 g/L corn steep liquor instead of yeast extract, 96 h fermentation, using Propionibacterium freudenreichii with 5% v/v, and continuous feeding of lactose by 0.04 L/h rate. The results showed that the highest level of vitamin B12 was at concentration of 30 mg/L, production yield of 14.48 mg/g, and productivity of 7.5 mg/L.day
Keywords: Vitamin B12, Propionibacterium freudenreichii ssp. shermanii, Fed Batch System, Plackett-Burman Design, Fermentor
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