الفهرس 
Determination of certain metabolitesOnly 14 pages are availabe for public view
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Abstract
The interactive effects of some vitamins folic acid (vitamin B9), ascorbic acid (vitamin c), or cobalamin (vitamin B12) and / or NaCl salt stress (at concentrations 100, 200, and 300 mM) on germination, seedling growth and on some relevant metabolic changes of flax (Linum usitatissimum) seeds were studied. The germination was completely inhibited in response to the higher concentration of NaCl (300 mM). Moreover, Salinity induced marked increases in soluble carbohydrate as well as glutathione, proline and malondialdehyde (a product of lipid peroxidation) which were concomitant with a sharp decrease in nucleic acids, total phenols, ascorbic acid and the total free amino acids as well as membrane stability index (MSI). Data also reveled that salinized flax seedlings accumulated high levels of Na, Cl, P and Mg while K as well as Ca ions were significantly decreased. Furthermore, NaCl treatment increased the activities of some antioxidant enzymes (superoxide dismutase, SOD, ascorbate peroxidase and oxidase, APX and ASO as well as peroxidase, POX and polyphenol oxidase, PPO). In contrast, a sharp decrease in catalase (CAT) and glutathione reductase, (GR) activities was recorded. On the other hand, completely non germinating flax seeds grown at 300 mM NaCl showed an amazing capacity for recovery and germinating after treatment with vitamins. The potentiation of these vitamins was mediated by accumulation of some osmoprotectants as total phenols, total free amino acids and proline associated with increasing of ascorbic acid and glutathione as well as some enzymatic antioxidants (CAT and GR). Thereby lowering the accumulation of MDA level and increasing membrane stability index of salinized flax seedlings.
Key words: flax; vitamins; antioxidant substances; antioxidant enzymes; salinity.