ABSTRACT
As part of our project on exploring Indonesian medicinal plants for antidiabetic and anticancer agents, this study was conducted to investigate the total phenolic and flavonoid contents, and antioxidant, cytotoxic and antidiabetic properties of R. tomentosa leaf extracts. The antioxidant activity was tested using DPPH, ABTS, and FRAP methods. In vitro cytotoxic assay was performed against MCF-7, HeLa, A549, and B16 cancer cell lines. The in vitro antidiabetic testing was determined using α-glucosidase and α-amylase inhibitory evaluation, while STZ-induced diabetic rats were used for in vivo study. The highest values of total phenolic (191.97 ± 0.19 mg GAE g-1) and flavonoid (29.11 ± 0.05 mg QE g-1) contents were recorded in methanolic extract. This extract also showed the highest DPPH and ABTS activities with IC50 values of 7.79 ± 0.03 and 4.03 ± 0.02 µg mL-1, respectively, as well as the highest FRAP activity with a value of 64.05 ± 0.54 µM Fe2+ g-1. The methanol extract had cytotoxicity against MCF-7, HeLa, A549, and B16 cancer cell lines with IC50 values of 123.49 ± 0.79, 28.28 ± 0.17, 168.88 ± 1.14, and 42.44 ± 0.18 µg mL-1, respectively. In vitro antidiabetic evaluation indicated that the MeOH extract inhibited α-glucosidase and α-amylase with IC50 values of 45.73 ± 1.06 and 41.31 ± 1.12 µg mL-1, respectively. A dose of 400 mg kg-1 body weight of the MeOH extract reduced rats' blood glucose rate and serum blood glucose by 48.51% and 17.73%, respectively after 15 days of treatment. Taken together, these findings suggested that the methanolic extract of R. tomentosa leaves can be used as a potential source of antioxidant, cytotoxic, and antidiabetic agents.
ABSTRACT
Dengue fever and dengue hemorrhagic fever are transmitted to humans by the Aedes aegypti and Aedes albopictus mosquitoes, with an observed 30-fold increase in global incidence the last 50 years. Despite the tremendous efforts invested anti-dengue virus research, no clinically approved vaccine or antiviral chemotherapeutics are available for humans, and disease treatment is limited to supportive care. Over the years there has been a continuous interest in the chemistry of metal complexes with biological activity, including platinum complexes with antitumor activity and silver complexes with antimicrobial action. Aim of the project was to investigate [Cu(2,4,5-triphenyl-1Himidazole) 2 (H2O)2].Cl2 as antiviral compound that was further tested for inhibitory effect on the replication of dengue virus type 2 (DENV-2) in Vero cell. DENV-2 were infected in Vero cells and replication of virus was measured by Viral ToxGlo with selectivity index value (SI) and determined as the ratio of cytotoxic concentration 50 (CC50) to inhibitory concentration 50 (IC50) for compound. The standard curve between concentration of compound (µg/mL) and %viability of cells was analyzed by logarithmic correlation regression with regression equation. For infection rates, t-test was used to examine the statistical significances among the concentrations of compound. P<0.05 was considered to be significant. The maximum inhibitory concentration (IC50) of [Cu(2,4,5- triphenyl-1H-imidazole)2 (H2O)2].Cl2 against DENV-2 was 98.62 µg/mL. The cytotoxic concentration (CC50) of compound against Vero cells was 300.36µg/mL. The SI values for [Cu(2,4,5-triphenyl-1H-imidazole)2 (H2O)2].Cl2 1.86.Based on selectivity index values, [Cu(2,4,5-triphenyl-1H-imidazole)2 (H2O)2].Cl2 can inhibit the growth of DENV- 2 and has low toxicity values for Vero cells.
ABSTRACT
BACKGROUND: Dengue is a kind of infectious disease that was distributed in the tropical and sub-tropical areas. To date, there is no clinically approved dengue vaccine or antiviral for humans, even though there have been great efforts towards this end. Therefore, finding the effective compound against dengue virus (DENV) replication is very important. Among the complex compounds, copper(II)-imidazole derivatives are of interest because of their biological and medicinal benefits. MATERIALS AND METHODS: In the present study, antiviral activity of [Cu(2,4,5-triphenylimidazole)2]n, was evaluated against different stages of dengue virus type 2 (DENV-2) replication in Vero cell using focus forming unit reduction assay and quantitative ELISA. RESULTS: [Cu(2,4,5-triphenylimidazole)2]n inhibited DENV-2 replication in Vero cells with IC50 = 2.3 µg/ml and SI= 19.42 when cells were treated 2 days after virus infection, whereas its CC50 for cytotoxicity to Vero cells was 44.174 µg/ml. CONCLUSION: The compound has high anti-DENV2 activity, less toxicity, and a high possibility to be considered a drug candidate.
ABSTRACT
Aldrin and its metabolite dieldrin are persistent organic pollutants that contaminate soil in many parts of the world. Given the potential hazards associated with these pollutants, an efficient degradation method is required. In this study, we investigated the ability of Pleurotus ostreatus to transform aldrin as well as dieldrin in pure liquid cultures. This fungus completely eliminated aldrin in potato dextrose broth (PDB) medium during a 14-day incubation period. Dieldrin was detected as the main metabolite, and 9-hydroxylaldrin and 9-hydroxyldieldrin were less abundant metabolites. The proposed route of aldrin biotransformation is initial metabolism by epoxidation, followed by hydroxylation. The fungus was also capable of degrading dieldrin, a recalcitrant metabolite of aldrin. Approximately 3, 9, and 18% of dieldrin were eliminated by P. ostreatus in low-nitrogen, high-nitrogen, and PDB media, respectively, during a 14-day incubation period. 9-Dihydroxydieldrin was detected as a metabolite in the PDB culture, suggesting that the hydroxylation reaction occurred in the epoxide ring. These results indicate that P. ostreatus has potential applications in the transformation of aldrin as well as dieldrin.
