Anti-enterovirus activity and active compounds of Ampelopsis brevipedunculata (Maxim.) Trautv
| Autor: | Hsing-Wen Hsu, 許馨文 |
|---|---|
| Rok vydání: | 2011 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 100 In this study, 58 selected meicinal plants were extracted with 95% ethanol and screened for their anti-EV71 activity with neutralization method. We investigated the antiviral modes of the extract with the time of addition assay and the effect of the extract on immune modulation in the EV71 infected host cell. Among 58 screened medicinal plants, 6 extracts inhibited all test EV71 strains including Ampelopsis brevipedunculata (Maxim.) Trautv (ABT), Euchresta formosana (Hayata) Ohwi, Ficus pumila L, Lemmaphyllum microphyllum Presl, Melastoma candidum D. Don and Spatholobi Caulis. The loweset average 50% inhibitory concentration (IC50) was observed in ABT extract of 32.20 μg/ ml. Among different solvent extracts of ABT, the acetone extract showed good antiviral effect on EV71 and coxsackievirus B3 (CVB3). The average IC50 of acetone extract against EV71 and CVB3 were 26.11 and 45.83 μg/ ml, respectively, 4 and 6% of that of the positive control (ribavirin). Acidic pH treatments decreased anti-EV71 activity of the extract. The inhibition rate of the pH 2 treated extract decreased to 50 ~ 70% of that of the original extract. The anti-EV71 modes of the ABT extract included viral infection prevention, viral inactivation and anti-viral early replication. The main anti-CVB3 modes of the ABT extract were viral inactivation and anti-viral replication. The ABT extract significantly increased the interlukin-6 (IL-6) and IL-1β and decreased the IL-8 levels in the EV71-infected cells. In summary of resusts for the anti-EV71 activity and immunomodulatory effect of ABT, high amounts of IL-6 induction in the infected-cells had high correlation with the anti-viral replication of the ABT extract and the decreasing IL-8 level was mostly contributed by the antioxidant activity of ABT. The ABT acetone extract was subjected to amberlite XAD-7, sephadex LH-20 and semi-pre C18-HPLC column chromatography to obtain six active fractions. Among them, fraction E-8-II and E-8-IV exhibited good anti-EV71 and anti-CVB3 activity. From the spectra of H-NMR, C-NMR, ESI-MS, FTIR and UV for the fractions E-8-II and E-8-IV, they were identified as prodelphinidin B3-3-O-gallate and procyanidin B2-3-O-gallate, respectivley, which had been firstly reported their anti-EV71 and anti-CVB3 activitly with the IC50 of 1.14 ± 0.09 ~ 153.58 ± 12.87 μg/ml (prodelphinidin B3-3-O-gallat) and 0.76 ± 0.09 ~ 71.16 ± 1.83 μg/ml (procyanidin B2-3-O-gallate), respectively. Procyanidin B2-3-O-gallate shows great antienterovirus effect and had higher content of the extract (5.67 mg / g crude extract), which was the main anti-EV71 compound of the ABT acetone extract. From the result of the time of addition assay, the anti-EV71 and anti-CVB3 modes of procyanidin B2-3-O-gallate included viral infection prevention, viral inactivation and anti-viral replication. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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