ABSTRACT
Objective: Detection of different serotypes of dengue virus and provide information on origin, distribution and genotype of the virus. Methods: Dengue virus serotypes identified as DEN-1 and DEN-2 were amplified and sequenced with E gene. The consensus sequences were aligned with references E gene sequences of globally available GenBank. Phylogenetic analysis was performed using Neighbor-joining and Kimura 2-parameter model to construct phylogenetic tree. Results: A total of 53 dengue virus isolates were positive, of which 38 [71.7%] were DENV-1 and 15 [28.3%] were DENV-2. Phylogenetic tree of DENV-1 and DENV-2 showed that the isolates were clustered in genotype I and cosmopolitan genotype, respectively considered the predominant genotypes in Southeast Asian countries. The molecular epidemiology genotype I DENV-1 and cosmopolitan genotype DENV-2 have been co-circulating in Klang Valley areas, Malaysia without shifting of genotype. Conclusion: The study reveals that DENV-1 and DENV-2 have been circulating in Malaysia. The isolates are clustered in genotype 1 and cosmopolitian genotype, respectively. The study results would help in planning for prevention and control of dengue virus in Malaysia
ABSTRACT
The methanolic extract obtained from the leaves of Tabernaemontana divericata (Family: Apocynaceae) was evaluated for in vitro antioxidant potential by determination of total antioxidant capacity, assay of nitric oxide scavenging activity and reducing power test. The extract was also screened for its cytotoxic effect using brine shrimp lethality bioassay. The results revealed potent antioxidant property in all antioxidant assays compared to the reference antioxidant, ascorbic acid in a dose dependent manner. Further, the methanolic extract of Tabernaemontana divericata showed significant cytotoxic effect (LC50: 3.12μg/ml) compared with positive control, Vincristine Sulphate (LC50: 0.331μg/ml).