Effects of NaCl Treatment on Growth and Antioxidant Activity of Mints

Abstract

To determine the metabolic response of salt stress in mint, the growth and physiological responses to NaCl were investigated. The growth and physiological metabolic reactions to salt concentration were compared in six species mints including peppermint(Mentha × piperita), eau de cologne(Mentha × piperita f. citrata), chocomint(Mentha × piperita f. citrata 'Chocolate'), spearmint(Mentha spicata), applemint(Mentha suaveolens), pineapplemint(Mentha suaveolens 'Variegata'). Plant height, leaf length, and leaf width decreased as salt concentration increased. Shoot fresh weight in the low salt concentration treatment was slightly higher than the control. Antioxidant activity, total polyphenols and total flavonoids increased in mint to salt stress with different reponses by species. Chocomint and spearmint had high salt resistance, antioxidant activity, total polyphenols, and total flavonoids. The growth of spearmint was significantly different to salt concentration. On the other hand, applemint was sensitive to salts and had lower values of antioxidant activity, total polyphenols, and total flavonoids. Keywords: Herb, Antioxidant activity, Total polyphenols, Total flavonoids