Essential oil components, antioxidant capacity, and fatty acid profile of water mint (Mentha aquatica L.) as affected by various drying methods

Purpose: The drying process is an outstanding factor influencing secondary metabolites in medicinal plants. Although the impact of drying techniques has been addressed in some medicinal plants, there is limited data to describe the essential oils (EO) and fatty acids (FA) profiles in aerial parts of medicinal plants using traditional and modern drying techniques. Research method: This research compared the EO content and composition, antioxidant capacity, and FA profile of aerial parts of water mint (Mentha aquatica L.) dried using various techniques, including sun, shade, conventional oven and vacuum oven (each of them at ۴۰, ۴۵, and ۵۰ °C), and microwave (۲۰۰, ۴۰۰, and ۶۰۰ W). Findings: The results showed that the minimum antioxidant potential (with maximum IC۵۰: ۱۱۳ µg mL⁻¹) was reported in sun-exposed samples. At the same time, the highest EO content was found in shade-dried samples, followed by oven at ۴۰ °C and vacuum at ۴۰ °C. The primary EO compounds were ۱,۸-cineole, menthol-furan, trans-caryophyllene, germacrene D, and viridiflorol. Shade and oven drying resulted in higher monoterpenes, while vacuum and microwave drying led to elevated sesquiterpenes. Vacuum drying at ۴۰ °C produced the highest levels of saturated fatty acids, but microwave drying, specifically at ۶۰۰ W, had the highest levels of polyunsaturated fatty acids compared to other drying methods. According to agglomerative hierarchy clustering (AHC) results, fresh samples were grouped with shade-drying. Research limitations: There was no limitations. Originality/Value: The current study shows that, after suggesting shade conditions, we may use the oven at low temperature and vacuum to produce water mint products of excellent quality.

کلیدواژه ها:

Linolenic acid ، Monoterpenes ، Palmitic acid ، Sesquiterpenes ، trans-Caryophyllene ، ۱ ، ۸-cineole