LED light sources improved the essential oil components and antioxidant activity of two genotypes of lemon balm (Melissa officinalis L.)

Abstract Background Nowadays, light-emitting diodes (LEDs) as a new lighting technology, have been emerged an alternative source of light for plants due to their wavelength specificity, the narrow width bands, small size, solid structure, long lifetime, and low heat generation. Here we investigated effect different LED sources on essential oil components antioxidant activity Melissa officinalis . Two genotypes lemon balm (Ilam Isfahan) were subjected four artificial treatments, including white, red, blue, red + blue LEDs, greenhouse natural lighting. Results The lights significantly increased shoot fresh dry weights leaf number in two compared condition. results showed that content composition variable under treatments total amount compounds Ilam genotype was higher than other genotype. analysis by GC/MS indicated highest monoterpenes related citronellal lamps (15.3 17.2% Isfahan genotypes, respectively) but condition had most sesquiterpenes both genotypes. observed variation between essentials relative percentage constituents not appearance or lack specific component. Red also provided radical scavenging (80.77 82.09% respectively). Based principal component analyses (PCA), three main groups identified regarding all treatments. Conclusions Overall, affected qualitatively quantitatively sources; hence, might be used improve monoterpenes, sesquiterpenes, selected