Antioxidant Activity and Volatile and PhenolicProfiles of Essential Oil and Different Extracts of Wild Mint (Mentha longifolia) from the Pakistani Flora

[摘要] The antioxidant activity and free radical scavenging capacity of the essential oil and three different extracts of wildly grownMentha longifolia(M. longifolia) were studied. The essential oil fromM. longifoliaaerial parts was isolated by hydrodistillation technique using Clevenger-type apparatus. The extracts were prepared with three solvents of different polarity (n-hexane, dichloromethane, and methanol) using Soxhlet extractor. Maximum extract yield was obtained with methanol (12.6 g/100 g) while the minimum with dichloromethane (3.50 g/100 g). The essential oil content was found to be 1.07 g/100 g. A total of 19 constituents were identified in theM. longifoliaoil using GC/MS. The main components detected were piperitenone oxide, piperitenone, germacrene D, borneol, andβ-caryophyllene. The total phenolics (TP) and total flavonoids (TF) contents of the methanol extract ofM. longifoliawere found to be significantly higher than dichloromethane and hexane extracts. The dichloromethane and methanol extracts exhibited excellent antioxidant activity as assessed by 2,2′-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging ability, bleachingβ-carotene, and inhibition of linoleic acid peroxidation assays. The essential oil and hexane extract showed comparatively weaker antioxidant and free radical scavenging activities. The results of the study have validated the medicinal and antioxidant potential ofM. longifoliaessential oil and extracts.

[学科分类] 分析化学