ABSTRACT
This study was conducted to evaluate the effects of different artificial light sources on the growth characteristics and various biological activities of the Atractylodes macrocephala x Atractylodes japonica hybrid cv. 'Dachul', which is highly useful for medicinal purposes. The plant had the largest biomass with a plant height of 38.20 ± 1.95 cm when treated with microwave electrodeless light (MEL). The chlorophyll content of the plants treated with fluorescent light (FL) was 53.93 ± 1.05 SPAD and was the highest. The antioxidant effect, determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), was the highest with 92.7 ± 0.2% in plants treated with light-emitting diode (LED)-green light. Total phenol and flavonoid contents were significantly higher with 19.7 ± 0.5 mg GAE/g and 40.2 ± 2.2 mg QE/g in the sample treated with LED-green light, respectively. For antimicrobial activity using the minimum inhibitory concentration (MIC) technique, the inhibitory ability against Escherichia coli was at 0.25 mg/mL under LED-green light treatment. The whitening activity using tyrosinase enzyme showed the highest tyrosinase inhibitory ability at 62.1 ± 1.2% of the above extract treated with MEL light. To confirm the immune activity in lipopolysaccharide (LPS)-induced RAW 264.7 cells, NO production of inflammation-related substances was measured. In addition, the inflammation-related genes iNOS (inducible nitric oxide synthase), COX-2 (cyclooxygenase-2), and TNF-α (tumor necrosis factor-α) in the same sample were confirmed using reverse transcriptase (RT)-PCR, and the result showed that gene expression was suppressed compared with that in the control group. It is expected that Dachul plants treated with LED-blue light will play an important role in enhancing intracellular anti-inflammatory activity. From these results, the effect for various biological activities appeared in a significantly diverse spectrum in response to different wavelengths of artificial light sources in Dachul.
