Investigation the Changes in the Activity of Antioxidant Enzymes of Saffron Crocus Under Aluminum Stress

The aim of this study was to investigate the activity of antioxidant enzymes in saffron crocus under stress with aluminum. Aluminum is hydrolyzed to Al۳+ cations (toxic form of aluminum) under acidic conditions, which is a limiting factor for growth and plant products. Although the mechanism of toxicity of aluminum is not completely understood, there are numerous reports of its role in the production of reactive oxygen species and the induction of oxidative stress. Saffron crocuses were grown in liquid culture medium, so that only the base of the crocus was below the water surface and then they treated with aluminum at concentrations of ۰.۲, ۰.۶, ۰.۸, ۱, ۲, ۲.۵, ۵, ۱۰ and۲۰ mM. The saffron crocuses were then examined for the activity of guaiacol peroxidase, phenylalanine ammonia-lyase, superoxide dismutase, polyphenol oxidase and phenolic and proline content by Polle, Wang, Ries and Giannopolitis, Ghanati, Velioglu and Bates methods, respectively. Statistical analysis of the data was performed at p <.۰۵۰ using Spss software. Experimental results showed that the activity of superoxide dismutase, guaiacol peroxidase, phenylalanine ammonia-lyase, polyphenol oxidase and phenolic and proline content under treatment with aluminum increased significantly. The highest antioxidant activity of superoxide dismutase, guaiacol peroxidase, phenylalanine ammonia-lyase, polyphenol oxidase was at the concentration of ۱۰ mM, but the phenolic and proline content at the concentration of ۲۰ mM had the highest activity. In general, the phenolic content and superoxide dismutase enzyme had the highest antioxidant activity among others. The results showed that aluminum increased the proline, phenols and antioxidant activity of saffron crocuses by inducting oxidative stress and producing free radicals.

کلیدواژه ها:

Free Radicals ، Guaiacol peroxidase ، Heavy Metals ، Phenolic Content ، Proline ، Oxidative Stress