Content and Antioxidant Activity of Three Active Components in Different Organs of Lonicerae japonicae Thunb.

Lonicerae japonicae Thunb. was used as material to establish the high performance liquid chromatography(HPLC)method for simultaneously determining the content of chlorogenic acid,caffeic acid and galuteolin in different organs(flowers,leaves and stems)of Lonicerae japonicae Thunb..The antioxidant activities of extracts from different organs of Lonicerae japonica Thunb. were evaluated through DPPH· and ABTS⁺· free radical scavenging ability.Results showed that,three active components were separated by the HPLC method with a good linear relationship(R² ≥ 0.9997)and average recovery rates ranged from 89.45% to 102.35%. Therefore,the method was simple,accurate and highly reliable. The content of chlorogenic acid in the flowers was 27.22 mg·g^-1,followed by the stems(19.68 mg·g^-1)and the leaves(12.80 mg·g^-1). The content of luteolin in the stems was the highest,which was 2.31 mg·g^-1,followed by leaves(1.66 mg·g^-1)and flowers(1.07 mg·g^-1). The contents of caffeic acid in the flowers,leaves and stems were 1.18,1.05,0.93 mg·g^-1,respectively. The extracts from flowers showed the highest antioxidant activity to DPPH· and ABTS⁺· among three organs with IC₅₀ 0.07 mg·mL^-1 and 0.05 mg·mL^-1,and the extracts of stems and leaves also showed antioxidant capacity to some extent. Antioxidant capacity order was flowers>stems>leaves.