In vitro antioxidant analysis of flavonoids extracted from Artemisia argyi stem and their anti-inflammatory activity in lipopolysaccharide-stimulated RAW 264.7 macrophages

In this study, flavonoids were successfully extracted from Artemisia argyi stem, and their yield reached 15.3 mg/g dry A. argyi stem. The flavonoid extract from A. argyi stem had a purity of 88.58 % (w/w), meanwhile, which also contained 1.57 % (w/w) carbohydrates, 2.04 % (w/w) proteins and 7.81 % (w/w) polyphenols, respectively. In vitro antioxidant activity analysis showed the increased scavenging effects of flavonoid extract from A. argyi stem on 1,1-diphenyl-2-picrylhydrazyl, 2,2'-azinobis-di-(3-ethyl-benzothiazolin-6-sulfonic acid) diammonium salt, hydroxyl, and superoxide radicals in a concentration-dependent manner. Furthermore, the flavonoid extract from A. argyi stem exerted protective effects on lipopolysaccharide-stimulated RAW 264.7 macrophages via inhibiting the levels of tumor necrosis factor-alpha, interleukin-6, interleukin-1 beta, and nitric oxide free radicals. Overall, this work will provide guidance and help in the utilization of edible A. argyi as plant-based diet and its bioactive flavonoid extract as antioxidant and anti-inflammatory ingredients to improve the function, nutrition, and healthiness of foods.