ISSN:
1750-3841
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Standard vitamin calibration curves for the microbiological determination of thiamine, riboflavin, vitamin B6, vitamin B1 2, biotin, niacin and pantothenic acid were prepared to determine the minimal and maximal vitamin concentrations that may be assayed by various microorganisms and protozoa, and to determine the incubation periods required for the growth response of the microbial vitamin assays to stabilize. The effect of assay vessel size on growth of Tetrahymena pyriformis was also determined. Vitamin assays using Tetrahymena pyrijkmis were shown to have wider concentration limits than those of bacteria and yeast. Analyses based on Ochromonas danica and Ochromonas malhamensis possessed approximately equal vitamin concentration limits when compared to corresponding bacterial assay methods. Accepted vitamin assay methodology using microorganisms terminate vitamin assays when the growth response has stabilized. This study indicated that some test organisms such as Lactobacillus viridescens, (thiamine), Lactobacillus casei (riboflavin) and Saccharomyces uvarum (vitamin B6) do not achieve a point of stable response, thus requiring a defined incubation period. Tetrahymena pyriformis growth was depressed by use of small diameter assay vessels. Optimum response of this organism requires the use of flasks in which assay media, when dispensed, will have a large surface to volume ratio.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-2621.1978.tb02509.x
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