Effect of height and soil properties on some secondary metabolites of different organs of sweet violet (Viola odorata L.) in different natural habitats of Mazandaran province

Various environmental factors including altitude and soil properties affect the growth and production of plants in natural ecosystems. Sweet violet (Viola odoratata L.) is a gramineous and perennial plant of the Violaceae family and grows as a wildflower in the mountainous areas of northern Iran and some other regions of the country. This study was performed to compare the phytochemical properties and antioxidant activity of Viola odoratata L. shoot and root extracts in nine habitats of Mazandaran province in March 2020. To investigate the analysis, leaf, flower and root organs of the plant in the flowering stage were collected from nine habitats of Mazandaran province along with soil samples of these areas in March 2018. After collecting the root and shoot samples at the florescence stage and preparing methanolic extract through ultrasonic method, the phenolic and flavonoid contents were determined by Folin-Ciocalteu and aluminum chloride colorimetric methods, respectively, the antioxidant activities were assayed by Diphenyl Picrylhydrazyl (DPPH), and the anthocyanin contents of flowers were measured by Wagner method. According to the findings, phenolic contents of the flowers and leaves decreased and increased, respectively with increasing height, and percentage antioxidant activities of the flowers increased while the amount of flavonoids was not affected by the habitat altitude. Analysis of soil properties revealed that the anthocyanin contents of flowers increased under the effect of deficient absorbable phosphorus in habitat 3 (Firoozjah Babol) and habitat 6 (Mohammadabad Behshahr). Also in the study of secondary metabolites, Sweet violets in habitat 7 had 67.95% and 86.18% antioxidant activities in flowers and roots, respectively; leaf and root phenol contents of 142.32 mg/g and 55.21 mg/g, respectively, and 6.52 μmol/g flower anthocyanin, so it can be selected as the superior region, and samples from this region can be used as gene banks in sexual and asexual reproduction.