Vol. 7(27), pp. 3489-3493, 5 July, 2013 DOI: 10.5897/AJMR12.1641 ISSN 1996-0808 ©2013 Academic Journals http://www.academicjournals.org/AJMR African Journal of Microbiology Research Full Length Research Paper Quantitative determination of vitamin B 6 in dietary foods for special medical purposes by microbiological assay method Pınar KAYNAR Food Safety and Nutrition Research, Refik Saydam National Public Health Agency, 06100, Sıhhiye-Ankara, Turkey. Accepted 21 May, 2013 “Dietary food for special medical purposes” is defined as the foodstuffs that are specifically produced or formulated and consumed under medical supervision with the aim of establishing diets of patients. These foods labeled and marketed are generally liquid or powder products formulated to meet specific needs. The objective of this research was to quantitative determination vitamin B 6 (pyridoxine) in dietary foods for special medical purposes by the use of microbiological assay method. To this end, the quantity of vitamin B 6 in total 36 liquid dietary foods for special medical purposes was determined by disc inoculum method of microbiological assay using Neurospora sitophila ATCC 9276. The response of the organism to pyridoxine was determined by measuring the zone diameter of growth surrounding the inoculum disc, and the amount of vitamin B 6 from these foods ranged from 0.12 mg/100 mL to 0.76 mg/100 mL. In the statistical evaluation, the results were evaluated according to independent samples T-test. It was observed that the values determined for these foods were similar to the values declared on the labels of the foods. The results of the study have indicated that quantitative determination of vitamin B 6 in the foods can be achieved by the use of microbiological assay method. Also, it is approved that the values of vitamin B 6 declared on the labels of foods are accurate. Key words: Dietary food for special medical purposes, vitamin B 6 (pyridoxine), microbiological method. INTRODUCTION Dietary foods for special medical purposes are used to meet and/or support the entire nutritional needs of an individual who cannot receive adequate amount of nutrition by normal feeding procedure (mouth) for various reasons (loss of appetite, various diseases, opera- tions…etc). In Turkey, The Ministry of Health is respon- sible for the regulations and practices of import, export, production, and inspection of these foods according to the law of (No = 5996) ‘production, consumption, and inspection of foods as described in the amended law’ (Anon, 2010). Since these foods are not currently pro- duced in our country, they are only inspected for legal import and market controls. Dietary foods for special medical purposes contain vitamins. Vitamins are sub- stances that the body needs to grow and develop nor- mally. Vitamin B 6 is a water-soluble vitamin that exists in three major chemical forms pyridoxine, pyridoxal and pyridoxamine (Wrigth, 1954). The nervous and immune system in the body need vitamin B 6 to function effectively; and it is also essential for blood cell metabolism and protein metabolism (Bender, 1994). Various methods such as chemometric, electrochemi- cal, spectrophotometric, fluorometric, voltammetric, micro- biological and chromatographic have been used to deter- E-mail: pinarmkaynar@yahoo.com. Tel: +90 312 458 21 37. Fax: +90 312 458 23 83.