Varietal variability of less grown mints: influence on selected antioxidants

Genus Mentha belongs among the important part of spice, aromatic and medical plants. It includes a large amount of varieties and forms which are not spread generally because of low knowledgeability about possibilities of individual varieties using and also about their high content of bioactive substances. Five less-known varieties and forms (Mentha x piperita var. ´Danica´, Mentha x piperita var. ´Chocolate´, Mentha arvensis f. Banana, Mentha sp. f. Mojito, Mentha sp. f. White Grape) with different aroma and plant habitus were chosen to estimate the content of essential oils, chlorophyll a, chlorophyll b and carotenoids. From obtained results varietal variability of individual varieties and forms have been specified and compared with commonly used Mentha x piperita. The content of essential oils was estimated by steam distillation. The pigment content was determined by spectrophotometric measurement of absorbance at a wavelength of 649 nm (chlorophyll a), 665 nm (chlorophyll b) and 450 nm (carotenoids). The results showed that ´Danica´ and ´Chocolate´ varieties have reached the highest amount of essential oils. Most of the chlorophyll a, b and carotenoids content reached commonly used Mentha x piperita, but there wasn´t found significant difference when compared with ´Danica´ and ´Chocolate´. The effect of varietal variability on the content of qualitative characteristics in the case of essential oils, chlorophyll a and b was confirmed according to used statistical analyse (p <0.05). The varietal variability of tested mint forms and varieties on carotenoids content was not confirmed.