Triterpenoid Pentacyclic Antimalarial Activity from the Leaves of Erythrina variegata

In the course of our continuing research for novel antimalarial agent from Indonesian plants, the methanol extract of the Erythrina variegata leaves showed significant antimalarial activity against Plasmodium falciparum strain K1 in vitro with IC50 6.8 μg/mL. The methanol extract was separated by using variety of chromatography techniques. The chemical structure of an antimalarial compound was determined on the basis of spectroscopic evidence and compared to previous data then this compound is identified as a pentacyclic triterpenoid oleane derivative, namely 3,22,23-trihydroxy-oleane-12-ene. The pentacyclic triterpenoid, 3,22,23-trihydroxy-oleane- 12-ene showed antimalarial activity against 3D7 and K1 strains with IC50 4.3 μg/mL and 24 μg/mL, respectively. These results strongly suggested that E. variegata is a promising sources of antimalarial agents

Eurycomanone induce apoptosis in HepG2 cells via up-regulation of p53

Background: Eurycomanone is a cytotoxic compound found in Eurycoma longifolia Jack. Previous studies had noted the cytotoxic effect against various cancer cell lines. The aim of this study is to investigate the cytotoxicity against human hepato carcinoma cell in vitro and the mode of action. The cytotoxicity of eurycomanone was evaluated using MTT assay and the mode of cell death was detected by Hoechst 33258 nuclear staining and flow cytometry with Annexin-V/propidium iodide double staining. The protein expression Bax, Bcl-2, p53 and cytochrome C were studied by flow cytometry using a spesific antibody conjugated fluorescent dye to confirm the up-regulation of p53 and Bax in cancer cells. Results: The findings suggested that eurycomanone was cytotoxic on cancerous liver cell, HepG2 and less toxic on normal cells Chang's liver and WLR-68. Furthermore, various methods proved that apoptosis was the mode of death in eurycomanone-treated HepG2 cells. The characteristics of apoptosis including chromatin condensation, DNA fragmentation and apoptotic bodies were found following eurycomanone treatment. This study also found that apoptotic process triggered by eurycomanone involved the up-regulation of p53 tumor suppressor protein. The up-regulation of p53 was followed by the increasing of pro-apoptotic Bax and decreasing of anti-apoptotic Bcl-2. The increased of cytochrome C levels in cytosol also results in induction of apoptosis. Conclusion: The data suggest that eurycomanone was cytotoxic on HepG2 cells by inducing apoptosis through the up-regulation of p53 and Bax, and down-regulation of Bcl-2

ANTI-MALARIAL COMPOUND FROM THE STEM BARK OF Erythrina variegata

During the course of our continuing search for novel anti-malarial compounds from Indonesian plants, the methanol extract of the bark of E. variegata showed significant anti-malarial activity toward Plasmodium falciparum in vitro using the lactate dehydrogenase (LDH) assay. The methanol extract of the bark of E. variegata  was separated by using bioassay-guide fractionation. The ethyl acetate fraction showed the most activity, exhibiting equipotency against both strains of parasite with IC50 of 23.8 µg/mL against 3D7 and 9.3 µg/mL against K1. Furthermore, by using the anti-malarial activity to follow separation, the ethyl acetate fraction was separated by combination of column chromatography to yield an active compound. The chemical structure of active compound was determined on the basis of spectroscopic evidences and comparison with those previously reported and identified as an isoflavonoid, warangalone. The warangalone showed anti-malarial activity against both strains of parasite used with IC50 of 4.8 µg/mL against 3D7 and 3.7 µg/mL against K1.   Keywords: Antimalarial, Erythrina variegata, warangalon

In vitro antiplasmodial properties of selected plants of Sabah

The antiplasmodial activity of the crude extracts of thirty plant species collected from Sabah was evaluated using chloroquine-sensitive strain (D10) and chloroquine-resistant strain (Gombak A) of Plasmodium falciparum. Significant activities were observed for the bark extract of Polyalthia insignis (IC50 3.89 and 11.89 µg/ml against Gombak A and D10, respectively), the leaf extracts of Kopsia dasyrachis (4.62 µg/ml against Gombak A) and Litsea elliptibacea (IC50 8.88 µg/ml against Gombak A), as well as the leaf and bark extracts of Neouvaria acuminatissima (IC50 6.90-10.08 and 0.69 µg/ml against Gombak A and D10, respectively), and the bark extract of Polyalthia microtus (IC50 9.0 and 12.12 µg/ml against Gombak A and D10, respectively)

ANTI-MALARIALCOMPOUND FROM THE STEM BARK OF Erythr/na variegata

ABSTRACT During the course of our continuing search for novel anti-malarial compounds from Indonesian plants, the methanol extract of the bark of E. variegata showed significant.anti-malarial activity toward Plasmodium falciparum in vitro using the lactate dehydrogenase (LDH) assay. The methanol extract of the bark of E. varlegata was separated by using bioassay-guide fractionation. The ethyl acetate fraction showed the most activity, exhibiting equlpotency against both strains of parasite with IC50of 23.8 pg/mL against 3D7 and 9.3 pg/mL against K1. Furthermore, by using the anti-malarial activity to follow separation, the ethyl acetate fraction was separated by combination of column chromatography to yield an active compound. The chemical structure of active compound was determined on the basis of spectroscopic evidences and comparison with those previously reported and identified as an isoflavonold, warangalone. The warangalone showed anti-malarial activity against both strains of parasite used with IC50of 4.8 pg/mL against 3D7 and 3.7 pg/mL against K1

Safety Evaluation of Oral Toxicity of Carica papaya

The subchronic toxicity effect of the leaf extract of Carica papaya Linn. in Sprague Dawley (SD) rats was investigated in this study. The extract was prepared by dissolving the freeze dried extract of the leaves in distilled water and was administered orally to SD rats (consisted of 10 rats/sex/group) at 0 (control), 0.01, 0.14, and 2 g/kg body weight (BW) for 13 weeks. General observation, mortality, and food and water intake were monitored throughout the experimental period. Hematological and biochemical parameters, relative organ weights, and histopathological changes were evaluated. The study showed that leaf extract when administered for 13 weeks did not cause any mortality and abnormalities of behavior or changes in body weight as well as food and water intake. There were no significant differences observed in hematology parameters between treatment and control groups; however significant differences were seen in biochemistry values, for example, LDH, creatinine, total protein, and albumin. However, these changes were not associated with histopathological changes. In conclusion, the results suggested that daily oral administration of rats with C. papaya leaf extract for 13 weeks at a dose up to fourteen times the levels employed in traditional medicine practice did not cause any significant toxic effect

In vitro chemopreventive activity of an ethyl acetate fraction derived from hot water extract of orthosiphon stamineus in HepG2 cells

Orthosiphon stamineus (Lamiaceae) is a medicinal plant containing several biologically active components that have chemopreventive activity. To investigate the chemopreventive properties of O. stamineus, we studied the apoptotic activity of the ethyl acetate fraction (EAF) derived from the hot water extract of O. stamineus leaves on the human hepatocellular carcinoma cell line, HepG2. The sulforhodomine B assay indicated that the EAF inhibited the viability of HepG2 cells in a concentration dependent manner. Hoechst 33342 staining showed that EAF-treated cells exhibited typical apoptotic morphologic changes such as nuclear condensation and fragmentation. JC-1 assays indicated that the EAF disrupted the mitochondrial transmembrane potential of HepG2 cells in a dose-dependent manner. Western blot analysis revealed that the EAF activated caspase-3, caspase-8 and caspase-9, increased Bax expression, downregulated Bcl-2, decreased Cox-2 expression and decreased level of the NF-kB p65 in nucleus. HPLC-DAD analysis identified the major components in the EAF as rosmarinic acid (31.8%) and caffeic acid (20.2%). Taken together, our study suggests that the EAF has the potential to be developed as an agent for human liver cancer prevention