Enzymatic activity and antioxidant capacity in mint (Mentha piperita L.) under refrigerated storage.
The objective of this investigation was to study the effect of low temperatures over the enzymatic activity and antioxidant capacity in mint (Mentha piperita L.), behavior was quantified during storage at 6 and 10°C with respect to a control treatment (at room temperature), for this purpose, a laboratory experiment was conducted during a spring-summer cycle of 2011 at the University Autonomous of Chapingo, Texcoco, Mexico. The activity of enzymes, such as peroxidase (POD), polyphenol oxidase (PPO), superoxide dismutase (SOD) and catalase (CAT), was determined; as well as the antioxidant capacity (AC), total phenol (TP) and vitamin C (VC) content. The main result found is that the enzymatic activity of POD increased from 194,72 to 306.29 U/g of FW (fresh weight) at 10°C; the antioxidant activity also increased from 262,57 to 327,32 mm TEAC/g of WF at the same temperature. On the other hand, at 6°C and 10°C the contents of WF and VC increased, but the effect on the activity of SOD was inverse as it decreased from 53,68 to 26,22 U/g of WF. The treatment room temperature contributes to an increased activity of the PPO (90,02 U/g of WF). The use of refrigeration increased enzymatic activity of POD, PT contents and VC. Also it was found that the SOD activities decreased and the AC was greatly affected at a 10°C storage temperature.