Biotin content

The average value in the 10 histologically normal lyophilized brains assayed for biotin was 230 i ig/mg with a range of 210-240 p(ig/mg. Values for biotin content of lyophilized rat brain were the same as those for human brain. 

Alkaline extraction (for high biotin content foods) with Na2S203 9H2O plus NH4OH solution filtration ... 

Acid hydrolysis with H2SO4 and enzyme digestion (papain) for low biotin content foods... 

High biotin content Symmetry Shield C18 (50mmx2.1mm, 3.5 pm) ... 

Low biotin content heart-cut system Symmetry Shield Cl 8 (50mmx2.1 mm, 3.5pm)xVydac218TP5215 (150mmx2mm, 3.5pm)... 

Biotin is involved in many carboxylation and decarboxylation reactions in carbohydrate, fatty acid, protein, and nucleic acid metabolism. Milk is a fairly good source of this vitamin, generally providing about 3/xg/100 g. Pasteurization has a minimal effect on the biotin content of milk. 

The desugaring of cane juice concentrates the heat- and alkali-stable vitamins in the final molasses. Even after this accumulation, only myo-inositol may have reached the level of minimum dietary requirements.109 Niacin, pantothenic acid and riboflavin are also present in significant quantities109 the thiamine, pyridoxin, pantothenic acid, biotin and folic acid contents of molasses have been estimated by bioassay.110 111 The biotin content of Hawaiian and Cuban molasses was 2.1 and 1.7 gammas per gram, respectively.119 The antistiffness factor (closely related to stigmasterol) has been found in cane molasses.88 89 The distillery slop from the yeast fermentation of molasses is marketed as a vitamin concentrate this product also contains vitamins originating in the yeast. 

Cholera toxin B subunit-biotin labeled (lyophilized powder, biotin content 0.9mol/mol protein), peroxidase-labeled IgG anti-rabbit antibody (HRP-Ab, from goat, protein content 0.8mg/ml, affinity isolated antibody), anti-cholera toxin (from rabbit, protein content 48mg/ml, purified toxin from Vibrio cholerae), biotin monoclonal anti-rabbit IgG -y-chain specific (from mouse, protein content 4.2mg/ml), glucose oxidase-biotinamidocaproyl labeled (GOX-B, from Aspergillus niger, lyophilized powder containing 40-70% protein, 137 U/mg), polyoxyeth-ylene-sorbitan monolaurate (Tween 20), bovine serum albumin (fraction... 

Table 9-27 Biotin Content of Some Foods Product Biotin (ng/100 g)...

Fig. 2 In situ AFM images (left) and line scans (right) of biotinylated vesicles with a nominal diameter of 100 nm attached to a streptavidin monolayer, a A low biotin content (2 mol %) results in the adsorption of intact liposomes within the timescale of observation (about Ih) b a high biotin content (30mol%) yields planar lipid bUayers exhibiting a typical height of 5-6 nm...

In this way, it was possible to assign the two rate constants of vesicle adsorption kad and rupture krup to a number of ligand-receptor pairs represented by the biotin content of the liposomes. The procedure is shown in Fig. 5a-d. The solid lines denote the simulation while the gray dots are results from QCM measurements. The insets show the surface coverage at the... 

Pseudomonas fluorescens, biotin content of, VI, 189 Pseudopyridoxine, VI, 194 Psychoses,... 

A deficiency of biotin in humans may result from an unbalanced diet, alcohol abuse, side-effects of medication (e.g. with sulfonamides, antiepileptics), or genetic defects. In babies, this deficiency may appear after prolonged breastfeeding (> 4 months), as the biotin content of the mother s milk decreases. There has... 

A coenzyme role of biotin in the reaction catalyzed by oxaloacetate carboxylase has been proposed on the basis of studies made with the purified enzyme, which suggest a close association between the enzyme s biotin content and the catalytic properties of the protein. The purified enzyme preparation contains 3 mpg of biotin per mg of protein. Biotin as a CO2 carrier in the CO2 fixation reaction was further supported in studies made on enzyme preparations obtained from birds and mammalian livers. These preparations catalyze the reversible conversion of pyruvate into oxaloacetate in the presence of ATP. 

The first biotin tests for foods relied on microbiological principles, although some non-specific colorimetric tests were developed for biotin in pharmaceutical preparations. This chapter summarizes the important analytical techniques that have been employed, or are in use today, with emphasis on dairy products. The analytical techniques reported for the determination of biotin content can be categorized under (i) microbiological, (ii) biological. 

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