Biomaterial Database

[Determination of water-soluble vitamins B1, B2, B6 and B12 in milk using HPLC]. 1992

R Gauch, and U Leuenberger, and U Müller

Kantonales Laboratorium, Bern, Schweiz.

Simple methods of determining the water-soluble vitamins B1, B2, B6 and B12 in milk by HPLC are described. Compared to existing procedures, the following improvements can be realized. The oxidation of vitamin B1 to thiochrome is stopped by the addition of sodium sulphite. This step significantly increases repeatability. Thiochrome is then extracted with butan-1-ol, which results in fewer co-extracts and greater selectivity. After the hydrolysis of the 5-phosphates of the vitamin B6 (pyridoxine, pyridoxal and pyridoxamine), these three vitamers are determined by isocratic HPLC as DDS-ion-pairs and with fluorimetric detection. As only microbiological methods have so far been used for the determination of minute quantities of vitamin B12 in milk, a new HPLC procedure is proposed with a detection limit of 0.2 micrograms vitamin B12/L milk.

UI	MeSH Term	Description	Entries
D008892	Milk	The off-white liquid secreted by the mammary glands of humans and other mammals. It contains proteins, sugar, lipids, vitamins, and minerals.	Cow Milk,Cow's Milk,Milk, Cow,Milk, Cow's
D010084	Oxidation-Reduction	A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).	Redox,Oxidation Reduction
D011730	Pyridoxal	The 4-carboxyaldehyde form of VITAMIN B 6 which is converted to PYRIDOXAL PHOSPHATE which is a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid.
D011733	Pyridoxamine	The 4-aminomethyl form of VITAMIN B 6. During transamination of amino acids, PYRIDOXAL PHOSPHATE is transiently converted into pyridoxamine phosphate.
D011736	Pyridoxine	The 4-methanol form of VITAMIN B 6 which is converted to PYRIDOXAL PHOSPHATE which is a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. Although pyridoxine and Vitamin B 6 are still frequently used as synonyms, especially by medical researchers, this practice is erroneous and sometimes misleading (EE Snell; Ann NY Acad Sci, vol 585 pg 1, 1990).	Pyridoxin,Pyridoxine Hydrochloride,Pyridoxol,Pyridoxol Hydrochloride,Rodex
D002851	Chromatography, High Pressure Liquid	Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.	Chromatography, High Performance Liquid,Chromatography, High Speed Liquid,Chromatography, Liquid, High Pressure,HPLC,High Performance Liquid Chromatography,High-Performance Liquid Chromatography,UPLC,Ultra Performance Liquid Chromatography,Chromatography, High-Performance Liquid,High-Performance Liquid Chromatographies,Liquid Chromatography, High-Performance
D006868	Hydrolysis	The process of cleaving a chemical compound by the addition of a molecule of water.
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012256	Riboflavin	Nutritional factor found in milk, eggs, malted barley, liver, kidney, heart, and leafy vegetables. The richest natural source is yeast. It occurs in the free form only in the retina of the eye, in whey, and in urine; its principal forms in tissues and cells are as FLAVIN MONONUCLEOTIDE and FLAVIN-ADENINE DINUCLEOTIDE.	Vitamin B 2,Vitamin G,Vitamin B2
D012995	Solubility	The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Solubilities