Effect of Folate Analogues on the Activity of Dihydrofolate Reductase and Seedlings, Callus Growth of Nigella Sativa L. Plant.

The study included the effect of three compounds of folate analogues, sulfanilamide, trimethoprim and aminopterin on the growth of seedlings and callus of Nigella sativa plant. These compounds were added at concentration of (10-1-10-5) Molar. The average roots length and the rate of germination in seeds, treated with folate analogues before planting, differed with the type of folate analogue and the concentration used.
The fresh weight and the content of protein, DNA and RNA of callus at 15 and 30 days, were inhibited by the folate analogues.
The decrease in folate content and specific activity of dihydrofolate reductase of callus, grown on media containing inhibitors, was similar to the decrease in fresh weight, protein, DNA and RNA contents. Dihydrofolate reductase activity was not effected by the addition of sulfanilamide either to the In vivo or In vitro system.