Antioxidants 2-mercaptoethanol

Folacin extraction from foods generally begins with homogenization in neutral or mildly acidic solution (122-124,152,153). One study (152) demonstrated that an extraction at pH 7.85 provided the most efficient recovery of endogenous folate from plant and animal tissues a second extraction of the residual tissue significantly increased the completeness of the extraction procedure. The extractant should contain antioxidants, such as ascorbic acid, 2-mercaptoethanol, dithiothreitol, or a mixture thereof to protect the natural oxidation states of the folacin vitamers. 

Since glycerol dehydrogenase contains autoxidizable thiol groups, it is nessecary to perform these reaction in an inert atmosphere antioxidants such as dithiothreitol or mercaptoethanol deactivate the enzyme at higher concentrations and should be avoided in preparative applications. 

Methyl oleate N,N,N, N -Tetramethylethylenediamine Triethylamine intermediate, rubber accelerators Allyl mercaptan t-Butylamine Diethylamine Isopropylamine 2-Methylpropanal p-Phenylenediamine Piperidine intermediate, rubber additives Benzoyl chloride intermediate, rubber antioxidants 2-Methylpropanal intermediate, rubber chemicals Benzonitrile Bisphenol A n-Butylamine Cyclopentanone Diethanolamine Ethylene carbonate Ethylenediamine Hexamethyleneimine dl-Limonene 2-Mercaptoethanol... 

The other factor that needs to be taken into consideration during sample processing is the stability of folate vitamers. Stability of the vitamers differs with respect to the susceptibility to oxidative degradation, thermal, pH, and ultra-violet light [51]. Interconversion of folate vitamers occurs during sample preparation and analysis, for example, 5,10-methylenetetrahydrofolate dissociates from tetrahydrofolate and formaldehyde in the presence of mercaptoethanol (antioxidant) at low pH [49]. Furthermore, it has been argued that 5,10-methenyltetrahydrofolate is difficult to analyze on a reversed-phase (RP-18) HPLC column with a low pH mobile phase [13]. This is because interconversion of 10-formyltetrahydrofoIate to 5,10-methenyltetrahydrofolate occurs at low pH [18]. 

Hyperosmolarity caused a time- and concentration-dependent increase in interleukin-8 expression and secretion in 16HBE14o bronchial epithelial cells (Loitsch et al. 2000). These effects could be blocked by antioxidants, such as dimethyl sulphox-ide (0.5 %), l,3-dimethyl-2-thiourea (20 mM), dithi-othreitol (500 /2M), and P-mercaptoethanol (500 (M), suggesting an involvement of reactive oxygen intermediates in the signal transduction of hyperos-molarity-induced IL-8 synthesis. 

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