| Since the middle of 20th century Chinese scientists have put considerable effort and resources into the search for new antimalarial compounds extracted from Chinese traditional herbs. An antimalarial drug was finally isolated in 1971 and named artemisinin or qinghaosu. Its rapid action, low toxicity and powerful effect against falciparum malaria made it a favored subject for research. Now qinghaosu and some of it's derivatives are being used around the world as effective new antimalarial drugs in the fight against falciparum malaria, including multi-drug-resistant Plasmodium falciparum.In addition, recent studies also indicate that some qinghaosu derivatives have other bioactivities, including antiparasitic and anticancer activities. Research into qinghaosu and its derivatives has already produced and will no doubt continue to produce results of the utmost importance in the fight against malaria and other diseases.The requirements, however, is much more than the output According to the limitation of chemical synthesis and cell/tissue culture , cultivated Artemisia annua is the main source of the drug.Artemisinin is a plant secondary metabolity of Artemisia annua and it's level was regulation by both exogenous and endogenous factors such as temperature, light, sasonal variation , eicitor, plant growth regulator and so on. Salicylic acid (SA ) and abscisic acid (ABA ) ,as two important plant growth regulators, play an important role in plant secondary metabolism. Artemisinin, a sesquiterpene lactone containing an endoperoxide bridge, is a kind of phytoalexin. SA, a key signal molecular during systemic acquaired resistance(SAR),is related to the biosynthesis of phytoalexin. ABA ,a stress-resistance plant hormone can influence the secondary metabolism to stimulate phytoalexin biosynthesis. Till now, the work on potential regulation of SA and ABA to artemisinin biosynthesis was not found. In this work, Artemisia annua was treated with 0.005g/l. 0.05g/l. 0.5g/l SA and ABA .Contents of artemisinin was detected by ultraviolet spectrometer. The results indicated that SA can raise the level of artemisinin. Within the testing concentration, the level of artemisinin was increased while the SA concentration was increased and then the higher concentration trialsshowed a marked increase of artemisinin. It was also showed that contents of artemisinin in Artemisia annua treated with ABA was increased at first and decreased later with increasing ABA content. Preliminary results illustrated that proper concentration of ABA could increase the contents of artemisinin.Secondary metabolities remained in residue after extracting artemisinin may have effects on wheat seeds germination and seedling growth. Wheat seeds were treated with the solution of alcohol extract of the residues. The result indicated that the solution postponed seeds germination in the earlier and promote it later. The inhibit effect increased as concentration increased, and wheat seeds were completely inhibited at 50g ?L '. The elongation of seedling upper-ground part and underground part was inhibited, in addition, the fresh weight of root and seedling reduced. Comparing to die control group, seedling, at high concentration, was bended with sandy beige and the root changed rigidity with similar color. Both the seedling and the root was rotted, the vigor of seedling was severely weakened consequently. In addition, chlorophyll of the seedling decreased with increasing concentration, when at 25mg/ml, chlorophyll content was less than 60.13% of the control group. Root activity had the similar trends to change of chlorophyll, and it only reached 52.54% of the control group. The results above suggested that water absorbing was limited by the inhibition of root activity .Photosynthesis and the production of the photosynthesis was limited by the decrease of chlorophyll. Proline and MDA showed minute difference at low concentration(0-5mg/ml), while at highconcentration(>5mg/ml), they were both sharply increased respectively. The ability of absorbing water...
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