The effect of chitosan on antioxidant activity and secondary metabolites in medicinal plant Dracocephalum kotschyi

A wide variety of secondary metabolites are synthesized from primary metabolites by plants which had a vast range in the pharmaceuticals, food additives and industrial applications. In recent years the use of elicitors has opened a novel approach for the production of secondary metabolite compounds. Dracocephalum kotschyi is valuable herb because due to pharmaceutical compounds like Rosmarinic acid (RA), Quercetin and Apigenin. The current study, foliar application of chitosan (۰, ۱۰۰, ۴۰۰ mg/l) as elicitor was used to increase medicinal componds in D. Kotschyi. Foliar spray of chitosan on H۲O۲ content, amount of phenolics, flavonoids, Rosmarinic acid, Apigenin and the activity of antioxidant enzymes and L-phenylalanine ammonia- lyase (PAL) were investigated. After chitosan treatment, increased amounts of hydrogen peroxide (H۲O۲) that enhanced activity of antioxidant enzymes (gauical peroxidase and catalase). The application of chitosan significantly increased content of phenol and flavonoid. Also chitosan increased PAL activity that resulted in enhanced Rosmarinic acid content (up to ۱۳-fold). Content of Apigenin (anticancer flavonoid) showed ۱۶-fold enhance compared to the control plants. Chitosan can play a main signaling role in the activation of many plant defense responses and maybe affected the gene regulation and enzymes activity in metabolic pathway linked with the biosynthesis of special secondary metabolites. Therefore, chitosan was found to be a very effective elicitor that treatment of D. kotschyi leaves by chitosan caused huge increase in induction and production of important pharmaceutical compounds such as Rosmarinic acid and Apigenin.

کلیدواژه ها:

Elicitor ، Pharmaceutical compounds ، Phenol ، Rosmarinic acid