Studies On Dynamic Variation Of Active In Gredients In Leaves Of Lonicera Japonica

Honeysuckle(Lonicera japonica Thunb.) is a commonly used medicinal plant that plays an important role in the prescription of traditional Chinese medicines. Previous studies have shown that there have many active ingredients in honeysuckle leaves. However, most of the leaves have been abandoned leading to a great loss of potential medicinal resources. This study mainly focuses on the components analysis of honeysuckle leaves and compares those with flowers and green buds of honeysuckle in order to reveal the dynamic variation of the actives components of honeysuckle leaves in different harvest time. And the antibacterial effects of honeysuckle leaf extract from the different growing periods were also preliminary investigated in order to provide scientific and technical reference for the utilization of Honeysuckle leaves.The content mainly involves the following four parts:1. Study on the simultaneous determination of multiple active constituents in honeysuckle by HPLCA method to determine the contents of nine bioactive compounds, neochlorogenic acid, chlorogenic acid,caffeic acid, rutin, galuteolin, hyperoside, isochlorogenic acid C, luteolin and quercetin in the leaves of Honeysuckle were established by HPLC. The results showed that nine compounds were separated well.Among them, isochlorogenic acid C and chlorogenic acid had the relatively highest contents, next was galuteolin, and rutin. The content of neochlorogenic acid, hyperoside and caffeic acid was relatively low.And quercetin was not detected in the leaves of honeysuckle. The proposed method is simple, accurate and specific. As a result, it can be considered as a quality control method for honeysuckle or its medicinal preparations.2. Determination the active constituents in different parts of honeysuckleThe nine active components in honeysuckle leaves, flowers and green buds were determined by HPLC.The results indicated that the contents of galuteolin, luteolin, rutin and isochlorogenic acid C were higher in leaves than those of in flowers and green buds, and neochlorogenic acid content was similar in leaves and flowers. Quercetin could not be detected in all the samples. Total flavonoids were assayed by UV-VIS. The reference substance is rutin, with Na NO2-Al(NO3)3-Na OH as color agent. The results showed that the contents of total flavonoids in leaves and green buds of June were 6.68% and 7.38%, respectively. But theywere all higher than those of in flowers(6.35%). Volatile components were measured by GC-MS. The results showed that there were no significant differences of the main compositions among flowers, leaves and green buds, and most of the contents are hydrocarbons with the percentage of 66.07% in leaves,70.75% in flowers and 67.94% in green buds collected in June respectively.3. Studies on active components in leaves of honeysuckle in different harvest timeThe nine active components in leaves in different harvest time was investigated, and the results showed that a variety of active ingredients were higher in June. The content of chlorogenic acid C and chlorogenic acid were relatively high, and oppositely, the content of caffeic acids was relatively low. Hyperoside only exists in January, February, March, October and November, but quercetin had not been detected in all the twelve months of a whole year. Total flavonoids in different months were assayed by UV-vis, which showed that there was great difference in leaves in different harvest time. Compared to other months, the contents of total flavonoids in June(6.68%), July(6.56%) and December(6.02%) were relatively high.And there were significant differences of the volatile in the leaves collected in difference months of the year. The leaves collected in July have more species of compounds than those collected in any other month.The content of hydrocarbon compounds is the highest with 83.15% in the leaves collected in May.4. Study vitro antibacterial activity in different parts of honeysuckleThe antimicrobial effects of the extract of honeysuckle leaves, flowers and green buds on Staphlococcus aureus(SA), Extended spectrum β-Lactamase sphlococcus aureus(ESBLs-SA), Escherichia Coli(EC),Extended spectrum β-Lactamases Escherichia Coli(ESBL-EC) were measured by agar plate drilling method. All samples had antibacterial effect only on SA and ESBLs-SA. Leaves had the best inhibitory on SA and ESBLs-SA(bacteriostatic ring was 13 mm and 14 mm, respectively), even better than flowers(bacteriostatic ring was 12 mm and 11 mm, respectively) and green buds(bacteriostatic ring was 11 mm and 13 mm, respectively). The leaves collected in June have the best antibacterial effect.