Production and Quality of Menthol Mint Essential Oil and Antifungal and Antigerminative Activity

Abstract

Agricultural products certified as organic and free of pesticides cannot use synthetic chemicals in the production process. In this context, the search for new natural products appears as an alternative to the use of conventional pesticides, aiming to combat agricultural diseases. Menthol is a natural product obtained from plants that has importance in different branches of industry, mainly due to the feeling of freshness it provides in contact with skin and mucous. Menthol (70% - 90%) is the main compound of the menthol mint essential oil, followed by menthyl acetate (7% - 12%), which is an indicator of maturation. There are references to the period of maturation of menthol mint essential oil corresponds the period of flowering, on the other hand, are also presented evidence that the maturation of menthol mint essential oil is controlled by leaf expansion, namely with the physiological age of each leaf. Besides evaluating the essential oil production and quality extracted by hydrodistillation of young leaves (3rd to 5th node) and adult (6th to 8th node), was also proposed in this work to study the effect of menthol mint essential oil on the development of fungi of agricultural significance and commercial seeds of lettuce and tomato. After the extraction of the essential oil, was noted that adult leaves presented a higher content of essential oil, combined with the best commercial quality, showing higher levels of menthyl acetate and menthol. The menthol mint essential oil exhibited average fungitoxicity and antigerminative activity on Fusarium oxysporum , Rhizoctonia solani and Sclerotium rolfsii . On the other hand, menthol and terpineol, two essential oil components, showed the maximum fungitoxicity activity under this species and no inhibitory effect on the germination of lettuce and tomato.