Antioxidant Activity Constituents Of Stems And Leaves Of Lonicera Japonica Thunb.

Lonicera japonica Thunb., was common traditional chinese medicine having theproperty of clearing heat and removing toxicity, antibacterial and antiphlogistic, protectingliver and cholagogic. Stems and Leaves of Lonicera japonica Thunb.was a kind of offcut oftaking dry honeysucle flower from Lonicera japonica Thunb., always was discarded as awaste. The chemical constituents of the stems and leaves of L. japonica were very complex,many kinds compouds such as Phenolic acids, Flavonoids, Saponin, iridoids, lignans werediscovered by Scientists. Phenolic acids and Flavonoids are main Pharmacological activecomponents in Lonicera japonica Thunb.as a traditional chinese medicine, show excellentantioxidation activity. This paper summarizes the antioxidative constituents of Lonicera andthe progress in the study of antioxidant activity of Chinese herbal medicines. Using threedifferent methods for study on antioxidative activity of ethanol extract of stems and leaves ofLonicera japonica Thunb.Produced in Nanzheng Hanzhong Shaanxi Honeysuckle Lonicerabase. The chemical constituents20%ethanol phase and40%ethanol phase which wereproven have significantly antioxidative activity better than any other part were separated andpurified by chromatography, and the structure of the monomeric compounds were identified.1. The antioxidative activity of ethanol extract of stems and leaves of Lonicera japonicaThunb was evaluated by using three different methods （DPPH·, pyrogallol autooxidation andphenanthroline） with Vc as reference substance, and calculates IC₅₀value of clearance rate ofeach part extract of three radicals. The results are as follows:Result of scavenging DPPH· of ethanol extract of stems and leaves of Lonicera japonicaThunb: The40%ethanol phase show the highest antioxidative activity of scavenging DPPH·,IC₅₀value is44.2μg·mL^-1. The order of the antioxidative activity of scavenging DPPH·ofdifferent concentration ethanol extract: Vc＞40%Ethanol phase＞20%Ethanol phase＞60%Ethanol phase＞80%Ethanol phase＞Aqueous phase＞Ethanol phase;Result of scavenging O·2-of ethanol extract of stems and leaves of Lonicera japonicaThunb: The40%ethanol phase show the highest antioxidative activity of scavenging O·2-,IC₅₀value is138.9μg·mL^-1. The order of the antioxidative activity of scavenging O·2-·ofdifferent concentration ethanol extract: Vc＞40%Ethanol phase＞20%Ethanol phase＞60%Ethanol phase＞Ethanol phase＞Aqueous phase＞80%Ethanol phase;Result of scavenging·OH of ethanol extract of stems and leaves of Lonicera japonica Thunb: The40%ethanol phase show the highest antioxidative activity of scavenging·OH,IC₅₀value is84.0μg·mL^-1. The order of the antioxidative activity of scavenging·OH ofdifferent concentration ethanol extract: Vc＞20%Ethanol phase＞40%Ethanol phase＞60%Ethanol phase＞80%Ethanol phase＞Ethanol phase＞Aqueous phase.2. Eight compounds were isolated from the20%ethanol phase and40%ethanol phase ofethanol extract which were proven have significantly antioxidative activity of stems andleaves of Lonicera japonica Thunb by MARCCT, SGCCT, SPCCT, TLC, Recrystallizationand so on, which had been proved to be single compound by purity testing. Six of them weredetermined by CO-TLC, comparing the M.P., MS, EI-MS,13C-NMR and1H-NMR datawhich was found in the literature. They were β-sitosterol（1）, Ferulic acid（3）, Caffeic acid（4）,Chlorogenic acid（6）, Quercetin（7）,5,4’-dihydroy-7-methoxy-isoflovone（8）, respectivly.Among them, Compounds8was obtained from this plant for the first time.As a kind of traditional Chinese medicine, the effective components of organic phenolicacids and flavonoids of Lonicera japonica Thunb have many important pharmacologicalactivities including antioxidative activity. The paper made a systematic study on theantioxidative activity of ethanol extract of stems and leaves of Lonicera japonica Thunb,preliminarily determinated the more higher activity phases. Eight compounds have beenisolated from the higher activity phases, structure analysis showed that three compounds areorganic phenol, two compounds are flavones, all of them have good antioxidative activity.Stems and Leaves of Lonicera japonica Thunb has similar chemical composition andpharmacological function with flower, the results of the antioxidative components of theethanol extract can provide certain theory basis for exploitation and utilization of the plantresources.