Main Article Content
Growth and secondary metabolite contents in lettuce sprouts were investigated. Seeds of ‘Sweet Green’ and ‘Seafresh’ were treated to DBD plasma for 0, 60 and 240 s. Results indicated that the responses of growth and secondary metabolite accumulation in lettuce sprouts to DBD plasma differed depending on lettuce cultivars and DBD plasma exposure times. The 60 and 240 s DBD plasma treated seeds improved growth of ‘Sweet Green’ sprouts as dry weight increased 18.28 and 30.11 %, respectively, comparing to non-plasma treatment. However, growth of ‘Seafresh’ sprouts was not significantly different regardless of plasma treatments. Total phenolic contents of ‘Sweet Green’ sprouts grown from seeds exposed to 240 s DBD plasma enhanced by 25 % as compared with control, while those of ‘Seafresh’ sprouts were not statistically different among the treatments. Flavonoid contents of lettuce sprouts developed from seeds treated to 240 s DBD plasma was 8.32 % higher than that of the control. The greater DPPH scavenging capacities of lettuce sprouts occurred in DBD plasma treatments. The results obtained from this research indicated that DBD plasma was one of effective methods to enhance growth and secondary metabolite contents in lettuce sprout.
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