Growth changes and antioxidant activities of Romaine lettuce with plasma discharge water and bioblock treatment

Abstract

This study intended to analyze growth changes and antioxidant activities of Romaine lettuce by different treatments of microbubble plasma discharge water and bioblock (far-infrared radiation). Hydroponics were performed in smart farm environments, and the used Romaine lettuce was the Caesar's Green variety. The treatment conditions of Romaine lettuce (TRL) are as follows: TRL-1 was treated with plasma discharge water and 30 bioblocks, and TRL-2 was treated with plasma discharge water and 40 bioblocks. On the other hand, TRL-3 was not treated. Romaine lettuce was grown for a total of 49 days and the growth changes were measured at every seven days. In growth changes, TRL-2 was significantly higher (p<0.05) than other treatments in germination rate and weight, leaf length, and leaf count. The total polyphenol and flavonoid contents were analyzed as similar levels between the samples, but TRL-2 showed higher antioxidant activities in ABTS radical scavenging (%) compared to the other samples. As a result of this study, TRL-2 conditions are evaluated to affect the growth and antioxidant functions of Romaine lettuce.