بررسي زمان و جايگاه بيوسنتز آلكالوييدهاي تروپاتي درگياه تاتوره

Assay of the time and location of tropane alkaloids biosynthesis in Datura stramonium L.

In this investigation the biosynthesis of tropane alkaloids (atropine, scopolamine and hyocyamine) and its metabolism in vegetative and generative phase of Datura stramonium L. were studied. The results obtained from analysis of aqueous and alcoholic yield from different organs in vegetative phase, showed that: Tropane alkaloids production begins at the end of 2nd week of seed germination and it increases at the end of 10th week. Alkaloids analysis showed that during the vegetative period of the root, scopolamine was absent dnd in generative phases atropine was increased 4 times as compared to scopolamine during vegetative phase in stem, both scopolamine and atropine were found and ratio of atropine to scopolamine was about 3. During generative phase the ratio was found to be same as vegetative phase Alkaloid analysis during the vegetative phase of leaves indicated that alkaloids reached to during minimum level in this phase. and ratio of atropine to scopolamine was about 3:1. During generative phase the ratio was about 3:2. The presence of alkaloids in seed flower and capsule was investigated and in all cases tropane alkaloide was found. In mature seed, the amount of atropine was negligible, but scopolamine was detectable. Cytochemical studies using dragendrov indicator showed that in addition to the xylem tissue, there were some golden spots in the roots which specifies the transversal moving of alkaloids. These spots also were observed in parenchyma of stems. In the leaves, near the main and branched veins and particulars in the basic areas and dermal petioles these spots were traced.