Identification of antiviral secondary metabolites from sweet lemon grass, Cymbopogon nardus (L.) Rendle, inhibiting measles virus

An in vitro study was carried out to investigate the antiviral effects of sweet lemon grass (Cymbopogon nardus (L.) Rendle) on measles virus (MV). Crude extract of this plant were prepared using hexane and fractionation of this extract was done using column chromatography (CC). First CC produced...

Full description

Saved in:
Bibliographic Details
Main Author: Mardziah, binti Manas
Format: Thesis
Language:English
Published: 2014
Subjects:
Online Access:http://ir.unimas.my/id/eprint/8797/4/MARDZIAH%20BINTI%20MANAS%20%28fulltext%29.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
id my-unimas-ir.8797
record_format uketd_dc
spelling my-unimas-ir.87972023-03-28T07:35:17Z Identification of antiviral secondary metabolites from sweet lemon grass, Cymbopogon nardus (L.) Rendle, inhibiting measles virus 2014 Mardziah, binti Manas SB Plant culture An in vitro study was carried out to investigate the antiviral effects of sweet lemon grass (Cymbopogon nardus (L.) Rendle) on measles virus (MV). Crude extract of this plant were prepared using hexane and fractionation of this extract was done using column chromatography (CC). First CC produced a total of 20 combined fractions and further fractionation on selected fractions resulted in 77 combined subfractions. The toxicity of all fractions and subfractions towards Vero cells ranged from mildly toxic (50 μg/ml) to considerably non-toxic (600 μg/ml). In the antiviral test, majority of the fractions inhibited the production of MV-induced cytopathic effects (CPE) by more than 50%. Some of them were able to inhibit the CPE by more than 75%, which was similar to the activity showed by positive control, Ribavirin, which is 80%. Most of the subfractions conferred around 50% of protection to the cells, but majority of them had lower antiviral activity compared to their derived fractions.In an attempt to study the mode of antiviral action, pre-treatment and post-infection protocols were used. It was found that post-infection protocol was more effective among fractions, suggesting that the fractions may interfere with any of the steps in late stage of MV replication. However, the subfractions did not give any particular trend as to the most effective method of treatment. Active subfractions were then further purified using preparative thin layer chromatography (PTLC) and produced 11 isolated compounds. These compounds possess weak antiviral activity with majority of them inhibited less than 50% of virus CPE. Most of isolated compounds provided better protection to the cells in the pre-treatment protocol, suggesting that the potential sites of activity may include inhibition of virus binding and/or entry which can be mediated by a number of cellular receptors such as CD46 present on Vero cells. Meanwhile for the synergistic assay, the combination of Ribavirin with isolated compounds at lowest concentration (0.01 LC50) produced synergistic effect, either in one or both protocol. The clear synergistic tendencies displayed by these substances combination allows for the reduction of Ribavirin concentration, which minimizes toxicity and the probability of formation of resistance to this drug. This synergistic activity is probably connected to the different mechanisms of action of Ribavirin and isolated compound. Additional test, antiproliferation assay, showed that the isolated compounds possess weak activity towards human papillary ovarian adenocarcinoma (Caov-3) cancer cells as they were able to inhibit less than 50% of the cells growth at highest concentration tested. Result also showed that they were toxic to normal cells as their cytotoxic values on cancer cells (>400 μg/ml) were much higher than that of the normal cells (150 to 270 μg/ml) and the reference drug, Tamoxifen (150 μg/ml). The GCMS analysis revealed that majority of the active isolated compounds had more than one constituent that were accounted for their inhibitory activity. The constituents are made up of monoterpene, sesquiterpene and hydrocarbon that present commonly in the essential oil of C. nardus, such as methyl eugenol, citronellol and geraniol. Universiti Malaysia Sarawak, (UNIMAS) 2014 Thesis http://ir.unimas.my/id/eprint/8797/ http://ir.unimas.my/id/eprint/8797/4/MARDZIAH%20BINTI%20MANAS%20%28fulltext%29.pdf text en validuser masters Universiti Malaysia Sarawak, (UNIMAS) Faculty of Resource Science and Technology
institution Universiti Malaysia Sarawak
collection UNIMAS Institutional Repository
language English
topic SB Plant culture
spellingShingle SB Plant culture
Mardziah, binti Manas
Identification of antiviral secondary metabolites from sweet lemon grass, Cymbopogon nardus (L.) Rendle, inhibiting measles virus
description An in vitro study was carried out to investigate the antiviral effects of sweet lemon grass (Cymbopogon nardus (L.) Rendle) on measles virus (MV). Crude extract of this plant were prepared using hexane and fractionation of this extract was done using column chromatography (CC). First CC produced a total of 20 combined fractions and further fractionation on selected fractions resulted in 77 combined subfractions. The toxicity of all fractions and subfractions towards Vero cells ranged from mildly toxic (50 μg/ml) to considerably non-toxic (600 μg/ml). In the antiviral test, majority of the fractions inhibited the production of MV-induced cytopathic effects (CPE) by more than 50%. Some of them were able to inhibit the CPE by more than 75%, which was similar to the activity showed by positive control, Ribavirin, which is 80%. Most of the subfractions conferred around 50% of protection to the cells, but majority of them had lower antiviral activity compared to their derived fractions.In an attempt to study the mode of antiviral action, pre-treatment and post-infection protocols were used. It was found that post-infection protocol was more effective among fractions, suggesting that the fractions may interfere with any of the steps in late stage of MV replication. However, the subfractions did not give any particular trend as to the most effective method of treatment. Active subfractions were then further purified using preparative thin layer chromatography (PTLC) and produced 11 isolated compounds. These compounds possess weak antiviral activity with majority of them inhibited less than 50% of virus CPE. Most of isolated compounds provided better protection to the cells in the pre-treatment protocol, suggesting that the potential sites of activity may include inhibition of virus binding and/or entry which can be mediated by a number of cellular receptors such as CD46 present on Vero cells. Meanwhile for the synergistic assay, the combination of Ribavirin with isolated compounds at lowest concentration (0.01 LC50) produced synergistic effect, either in one or both protocol. The clear synergistic tendencies displayed by these substances combination allows for the reduction of Ribavirin concentration, which minimizes toxicity and the probability of formation of resistance to this drug. This synergistic activity is probably connected to the different mechanisms of action of Ribavirin and isolated compound. Additional test, antiproliferation assay, showed that the isolated compounds possess weak activity towards human papillary ovarian adenocarcinoma (Caov-3) cancer cells as they were able to inhibit less than 50% of the cells growth at highest concentration tested. Result also showed that they were toxic to normal cells as their cytotoxic values on cancer cells (>400 μg/ml) were much higher than that of the normal cells (150 to 270 μg/ml) and the reference drug, Tamoxifen (150 μg/ml). The GCMS analysis revealed that majority of the active isolated compounds had more than one constituent that were accounted for their inhibitory activity. The constituents are made up of monoterpene, sesquiterpene and hydrocarbon that present commonly in the essential oil of C. nardus, such as methyl eugenol, citronellol and geraniol.
format Thesis
qualification_level Master's degree
author Mardziah, binti Manas
author_facet Mardziah, binti Manas
author_sort Mardziah, binti Manas
title Identification of antiviral secondary metabolites from sweet lemon grass, Cymbopogon nardus (L.) Rendle, inhibiting measles virus
title_short Identification of antiviral secondary metabolites from sweet lemon grass, Cymbopogon nardus (L.) Rendle, inhibiting measles virus
title_full Identification of antiviral secondary metabolites from sweet lemon grass, Cymbopogon nardus (L.) Rendle, inhibiting measles virus
title_fullStr Identification of antiviral secondary metabolites from sweet lemon grass, Cymbopogon nardus (L.) Rendle, inhibiting measles virus
title_full_unstemmed Identification of antiviral secondary metabolites from sweet lemon grass, Cymbopogon nardus (L.) Rendle, inhibiting measles virus
title_sort identification of antiviral secondary metabolites from sweet lemon grass, cymbopogon nardus (l.) rendle, inhibiting measles virus
granting_institution Universiti Malaysia Sarawak, (UNIMAS)
granting_department Faculty of Resource Science and Technology
publishDate 2014
url http://ir.unimas.my/id/eprint/8797/4/MARDZIAH%20BINTI%20MANAS%20%28fulltext%29.pdf
_version_ 1783727995959115776