Phytochemical analysis of selected Nepeta species by HPLC-ESI-MS/MS and GC-MS methods and exploring their antioxidant and antifungal potentials

摘要

Phytochemical analysis, antioxidant and antifungal activity of Nepeta species (N. racemosa, N. saccharata, N. congesta, and N. cataria) were assessed. The amount of essential oil yield ranged from 0.31 (N. racemosa) to 1.76 % (N. congesta). The 4a alpha,7 alpha,7a beta-nepetalactone was the major compound in the essential oil of the N. racemosa (91.0 %), N. cataria (81.3 %) and N. saccharata (75.4 %). Also, in essential oil of N. congesta, 1,8-cineol (25.4 %) was the main component. The major phenolic acid was ferulic acid (8.03-26.08 g kg(-1)). The highest concentrations of ferulic acid, chlorogenic acid, caffeic acid, and coumaric acid were obtained in N. cataria. The most abundant flavonoid was rutin (0.02-0.51 g kg(-1)). The highest amounts of rutin, quercetin, and kaempferol were obtained in N. racemosa, N. saccharata, and N. cataria, respectively. As well as, the highest total phenolic (87.40 g GAE kg(-1) DW powder), flavonoid contents (1.99 g Qu/kg DW powder), and antioxidant capacity by DPPH (77.26 %) and FRAP (2.23 mu mol Fe++ g(-1) DW powder) were obtained in N. cataria. The antifungal assay showed that the use of >= 600 ppm of essential oil resulted in a fungicidal effect against funguses tested (Botrytis cinerea, Cladosporium fulvum, and Pyricularia oryzae). In the case of Stemphylium botryosum, their mycelial growth completely inhibited at concentrations like or superior than 600 ppm essential oil of N. saccharata and N. racemosa. The obtained results of present study can provide new safe resources to the development of new products for the food, agriculture, and pharmaceutical industries.