Comparison of growth characteristics, linarin content and antioxidant activity of <i>Chrysanthemum zawadskii</i> var. <i>latilobum</i> under different LED light intensities in a plant factory

Chrysanthemum zawadskii var.latilobum is a perennial herb native to Korea that contains various bioactive compounds.Linarin is known for its hepatoprotective, anti-inflammatory, and antioxidant activities, making it a promising functional raw material.However, the content of such secondary metabolites is significantly influenced by environmental factors like light.Therefore, research on the variation in secondary metabolites of C. zawadskii var.latilobum under different light intensities is required for successful plant factory cultivation.This study was conducted to determine the optimal light conditions for the production of functional compounds by comparing changes in the growth characteristics, linarin content, and antioxidant activity of C. zawadskii var.latilobum under different light intensity levels.Plants were cultivated for eight weeks under six light intensities (50, 100, 150, 200, 250, and 300 mol m -2 s -1 ), and growth parameters, chlorophyll content, linarin content, total polyphenol content (TPC), total flavonoid content (TFC), and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity were measured.The results showed that the highest biomass was observed at 250 mol m -2 s -1 , while linarin content peaked at 28.02 mg/g under 150 mol m -2 s -1 .TPC, TFC and Antioxidant activity increased with light intensity, with the highest levels observed at 300 mol m -2 s -1 .However, excessive light intensity led to a reduction in both biomass accumulation and linarin synthesis.These findings suggest that an LED light intensity range of 150-250 mol m -2 s -1 is optimal for balancing growth and functional metabolite production in C. zawadskii var.latilobum.