Light-emitting diode-induced ellagic acid production in Drosera tokaiensis inhibits advanced glycation end-product formation

Drosera tokaiensis (DT) is an insectivorous plant that effectively inhibits advanced glycation end products (AGEs) generated from non-enzymatic reactions between reducing sugars and protein amino groups using phenolic compounds, including ellagic acid, myricitrin, and quercitrin. The accumulation of AGEs increases during the pathogenesis of non-communicable diseases, such as diabetes and nephropathy. Therefore, the extracts of Drosera species could have preventive effects against such diseases. The development of light-emitting diodes (LEDs) and their use in plant cultivation and tissue culture can enhance secondary metabolite production by controlling the wavelength of light in which plants are cultivated. We evaluated how LEDs affected the production of AGE-inhibitory compounds in extracts isolated from DT tissue cultures. DT was cultured for two months in different light wavelengths under unified photosynthetic photon flex density and the resulting extracts were used to examine changes in phenolic compound content and the inhibition of AGE formation. Cultivation in monochromatic light from LEDs had no significant effect on plant weight compared to conventional fluorescent cultivation, except for red LED light. Ellagic acid content increased regardless of LED coloration and the production and accumulation of myricitrin and quercitrin were inhibited. The extracts isolated from plantlets cultured under LEDs showed the same level of AGE inhibition as those cultured under fluorescent light. Therefore, for anti-glycation activity, DT can be grown stably and at a low cost using LED lights when compared to conventional culture methods.