Alpha-mangostin, piperine and beta-sitosterol as hepatitis C antivirus (HCV): In silico and in vitro studies.

Hepatitis C is still a serious liver case of health. Up to now the development of anti-Hepatitis C Virus (HCV) drugs is challenging, especially the development of natural material compounds as anti-HCV. In the present study, we evaluated the probability of α-mangostin, piperine, and ß-sitosterol as anti-HCV with the in silico and in vitro approaches. Molecular docking was performed between nonstructural protein 5B (NS5B, PDB ID 3FQL) with α-mangostin, piperine, and ß-sitosterol by Autodock Tools® and BIOVIA Discovery Studio®. Subsequently, molecular dynamics simulations were conducted for 200 ns, evaluating the dynamic interaction between the ligands and the viral protein NS5B. Furthermore, compound characterization at the hepatocarcinoma cell line was employed. α-Mangostin with NS5B complex demonstrated the most negative binding free energy value based on MM-PBSA calculation with a value of -9.13 kcal/mol. In vitro test showed that IC50 of α -mangostin was 2.70 ± 0.92 µM, IC50 of piperine was 52.18 ± 3.21 µM, IC50 of ß-sitosterol was >100 µM. α-Mangostin can serve as a valuable lead compound for further development of the anti-HCV.

Identification of an Oligostilbene, Vaticanol B, from Dryobalanops aromatica Leaves as an Antiviral Compound against the Hepatitis C Virus.

Chronic hepatitis C virus (HCV) infection can lead to liver cirrhosis and hepatocellular carcinoma. Although current medications using direct-acting antivirals (DAAs) are highly effective and well-tolerated for treating patients with chronic HCV, high prices and the existence of DAA-resistant variants hamper treatment. There is thus a need for easily accessible antivirals with different mechanisms of action. During the screening of Indonesian medicinal plants for anti-HCV activity, we found that a crude extract of Dryobalanops aromatica leaves possessed strong antiviral activity against HCV. Bioassay-guided purification identified an oligostilbene, vaticanol B, as an active compound responsible for the anti-HCV activity. Vaticanol B inhibited HCV infection in a dose-dependent manner with 50% effective and cytotoxic concentrations of 3.6 and 559.5 µg/mL, respectively (Selectivity Index: 155.4). A time-of-addition study revealed that the infectivity of HCV virions was largely lost upon vaticanol B pretreatment. Also, the addition of vaticanol B following viral entry slightly but significantly suppressed HCV replication and HCV protein expression in HCV-infected and a subgenomic HCV replicon cells. Thus, the results clearly demonstrated that vaticanol B acted mainly on the viral entry step, while acting weakly on the post-entry step as well. Furthermore, co-treatment of the HCV NS5A inhibitor daclatasvir with vaticanol B increased the anti-HCV effect. Collectively, the present study has identified a plant-derived oligostilbene, vaticanol B, as a novel anti-HCV compound.

Antioxidant and Acetylcholinesterase Inhibitor Potentials of the Stem Extract of Pternandra galeata / Potenciales antioxidantes e inhibidores de la acetilcolinesterasa del extracto de tallo de Pternandra galeata

Background: Pternandra galeata belongs to the family Melastomataceae. It is a native flowering plant in Borneo Island that serve as food for monkey habitat. There has been limited study on the medicinal and chemical properties of this plant. Objectives: We investigated the acetylcholinesterase inhibitory activity and evaluated the antioxidant activity of the ethanolic extract of Pternandra galeata stem. The total phenolic content in the sample was also determined. Methods: The acetylcholinesterase inhibitory assays were performed using Ellman's method. Two different methods were used to evaluate the antioxidant activity of the extract by 2,2-diphenyl-1-picryl hydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. The total phenolic content was determined by the Folin-Ciocalteu method by employing gallic acid as a reference. Results: The ethanolic extract of the P. galeata stems inhibited the AChE enzyme with an IC50 value of 74.62 ± 0.89 µg/mL.The sample exhibited antioxidant activity in the DPPH assay with an IC50 value of 20.21 ± 0.08 µg/mL and 7.68 ± 0.09 µg/mL in the ABTS scavenging assay. The total phenolic content was 164.71 ± 3.33 mg GAE/g extract. Conclusion: The ethanolic extract of the P. galeata stem can be a promising cholinesterase inhibitor and antioxidant for treating Alzheimer's disease

Antecedentes: Pternandra galeata pertenece a la familia Melastomataceae. Se trata de una planta con flores nativa de la isla de Borneo que sirve de alimento para el hábitat de los monos. Se han realizado pocos estudios sobre las propiedades medicinales y químicas de esta planta. Objetivos: Se investigó la actividad inhibidora de la acetilcolinesterasa y se evaluó la actividad antioxidante del extracto etanólico del tallo de Pternandra galeata. También se determinó el contenido fenólico total de la muestra. Métodos: Los ensayos de inhibición de la acetilcolinesterasa (AChE) se realizaron mediante el método de Ellman. Se utilizaron dos métodos diferentes para evaluar la actividad antioxidante de los ensayos de 2,2-difenil-1-picril hidrazilo (DPPH) y 2,2'-azinobis-(ácido 3-etilbenzotiazolina-6-sulfónico) (ABTS). El contenido fenólico total se determinó por el método de Folin-Ciocalteu empleando el ácido gálico como referencia. Resultados: El extracto etanólico de los tallos de P. galeata inhibió la enzima AChE con un valor IC50 de 74.62 ± 0.89 µg/mL. La muestra mostró actividad antioxidante en el ensayo DPPH con un valor IC50 de 20.21 ± 0.08 µg/mL y 7.68 ± 0.09 µg/mL en el ensayo de barrido ABTS. El contenido fenólico total fue de 164.71 ± 3.33 mg GAE/g de extracto. Conclusión: El extracto etanólico del tallo de P. galeata puede ser un prometedor inhibidor de la colinesterasa y antioxidante para el tratamiento de la enfermedad de Alzheimer.

Artocarpus sericicarpus stem bark contains antimalarial substances against Plasmodium falciparum.

OBJECTIVES: The finding of alternative medicine for malarial treatment still has become a substantial demand. The plant is one of the potential sources of drugs, among other natural sources. Artocarpus species showed great potential as the antimalarial source. This study aims to obtain active antimalarial fractions from Artocarpus sericicarpus stem bark. METHODS: Stem bark of A. sericicarpus was extracted by ultrasonic-assisted extraction method using n-hexane, dichloromethane, and methanol as solvents. Fractionation of dichloromethane extract was conducted by open column chromatography using octadecyl silica as a stationary phase and gradient acetonitrile-water as a mobile phase. The antimalarial activity was determined by lactate dehydrogenase (LDH) assay against Plasmodium falciparum 3D7 strain. RESULTS: A. sericicarpus n-hexane, dichloromethane, and methanol extracts were showed antimalarial activity with an IC50 value of >4, 2.11, and >4 µg/mL, respectively. Fractionation of dichloromethane extract was obtained 13 fractions. Seven of the 13 fractions tested showed antimalarial activity. Fraction-6 performed the highest inhibition with an IC50 value of 1.53 ± 0.04 µg/mL. Phytochemistry screening revealed that Fraction-6 contains flavonoid, polyphenol, and terpenoid compounds that can take a role in its antimalarial activity. CONCLUSIONS: A. sericicarpus contains antimalarial substances mainly in Fraction-6, which strongly inhibited the growth of P. falciparum. The flavonoid, polyphenol, and terpenoid compounds were identified in Fraction-6, which need to be further isolated to obtain and elucidate the active antimalarial compounds.

Screening of anti-HIV activities in ethanol extract and fractions from Ficus fistulosa leaves.

OBJECTIVES: Human immunodeficiency virus (HIV) infection is considered as a major immunosuppressive disease linked to malignancies and other opportunistic infections. Recently, the high prevalence of HIV drug-resistant strains required a high demand for novel antiviral drug development, especially in herbal medicine approaches. The objective of this study was to evaluate the possibility of Ficus fistulosa leaves can inhibit HIV replication in ethanol extract form as well as its fractions using chloroform, ethyl acetate, and butanol solvents. METHODS: F. fistulosa leaves were extracted using ethanol as a solvent and further gradually fractionated in chloroform, ethyl acetate, and butanol solvents. The targeted persistently infected virus (MT4/HIV) cell lines were cocultured with ethanol extract and fractions at different time points. The syncytium formation and cytotoxicity assays were performed to evaluate the potential antiviral activity of F. fistulosa leaves. RESULTS: One of the four tested extract/fractions showed antiviral activity against HIV. The ethanol extract showed weak inhibition with a high level of toxicity (IC50 = 8.96 µg/mL, CC50 ≥50 µg/mL, and SI = 5.58). Meanwhile, chloroform fraction effectively inhibited the MT4/HIV cell proliferation while keeping the toxicity to a minimal level (IC50 = 3.27 µg/mL, CC50 = 29.30 µg/mL, and SI = 8.96). In contrast of ethyl acetate fraction and butanol fraction showed no anti HIV activity with a high level of toxicity (CC50 ≥50 µg/mL) and low SI value (>2.17 µg/mL and >0.97 µg/mL). CONCLUSIONS: Chloroform fraction of F. fistulosa leaves showed effectively as anti-viral activity against MT4/HIV cells.

Alkaloid and benzopyran compounds of Melicope latifolia fruit exhibit anti-hepatitis C virus activities.

BACKGROUND: New agents for developing alternative or complementary medicine to treat the hepatitis C virus (HCV) are still needed due to high rates of HCV infection globally and the current limitations of available treatments. Treatment of HCV with a combination of direct acting antivirals have been shown to be approximately 90% effective but will be limited in the future due to the emergence of drug resistance and high cost. The leaves of Melicope latifolia have previously been reported to have anti-HCV activity and are a potential source of bioactive compounds for future novel drug development. This study aimed to evaluate the efficacy of the extract of M. latifolia fruit to treat HCV and to isolate its active compounds. METHOD: M. latifolia fruit was extracted using methanol and purified using vacuum liquid chromatography (VLC) and Radial Chromatography. The anti-HCV activity was analyzed using cell culture lines Huh7it-1 and JFH1 (genotype 2a). Time-of-addition and immunoblotting studies were performed to identify the mode of action of the isolated active compounds. The structures of the active compounds were determined using nuclear magnetic resonance (NMR) spectra, UV, IR, and Mass Spectra. RESULTS: Six known compounds were isolated from M. latifolia fruit: O-methyloktadrenolon, alloevodionol, isopimpinellin, alloxanthoxyletin, methylevodionol, and N-methylflindersine. N-methylflidersine was the most active compound with IC50 value of 3.8 µg/ml while methylevodionol, isopimpinellin, and alloevodionol were less active. O-methyloktadrenolon and alloxanthoxyletin were moderately active with IC50 values of 10.9 and 21.72 µg/ml, respectively. N-methylflidersine decreased level of HCV NS3 protein expression in the cells. CONCLUSION: The alkaloid compound, N-methylflindersine which was isolated from M. latifolia possesses anti-HCV activity through post-entry inhibition and suppressed NS3 protein expression.

Calotroposid A: a Glycosides Terpenoids from Calotropis gigantea Induces Apoptosis of Colon Cancer WiDr Cells through Cell Cycle Arrest G2/M and Caspase 8 Expression

Objective: This study aims to isolate the active anticancer compound from ethyl acetate fraction extracted from the roots of Calotropis gigantea and to determine the operating mechanism of the isolates towards WiDr colon cancer cells. Methods: the isolation was conducted by using bioassay guided isolation approach method. The cytotoxic potential was determined by using MTT method. The chemical structure was identified by using UPLCMS/MS and NMR-1H spectroscopy. The cell cycle arrest and apoptosis induction were determined by flow cytometry method. The expression of caspase-8 was determined by immunocytochemistry method. Results: The results showed that the active compounds are obtained calotroposid A compound which is glycosides terpenoids. Calotroposide A is capable of inhibiting the growth of WiDr colon cancer cells at IC50 17.23µg/ml. Cell apoptosis induction took place and was indicated by cell apoptosis increase, S and G2/M accumulation and by caspase-8 expression. Conclusion: Calotroposide A induces anticancer activity against WiDr colon cancer cells by means of apoptosis induction mechanism through extrinsic pathway with increased expression of caspase-8.

Antiplasmodial Activity of Isolated Polyphenols from Alectryon serratus Leaves Against 3D7 Plasmodium falciparum.

BACKGROUND: Alectryon serratus was selected from a screening program devoted to search naturally occurring antimalarial compound from plants in Alas Purwo National Park, Banyuwangi, East Java, Indonesia. The previous studies showed that ethanol extract of A. serratus leaves contains some polyphenol compounds. OBJECTIVE: This study was designed to isolate and investigate antiplasmodial activity of polyphenol compounds. MATERIAL AND METHODS: The ethanol extract of A. serratus leaves was fractioned using liquid-liquid fractionation and column chromatography. Isolated compounds were identified using High-performance liquid chromatography, ultraviolet-visible, nuclear magnetic resonance, and compared with references. The isolates were tested in vitro for antiplasmodial activity against chloroquine-sensitive 3D7 strain of Plasmodium falciparum. Thin blood smears were used to assess the levels of parasitemia and growth inhibition of the isolates. RESULT: Half maximal Inhibitory concentration of Gallic acid (1), methyl gallate (2), and kempferol-3-O-rhamnoside (3) were 0.0722 µM, 0.0128 µM, and 3.4595 µM, respectively. CONCLUSION: The results suggest that gallic acid, methyl gallate, and kempferol-3-O-rhamnoside isolated from A. serratus leaves have antiplasmodial activity and are potential to be developed as antimalarial drugs. SUMMARY: The ethanol extract of Alectryon serratus leaves was successively fractionated in CH2Cl2, EtOAc, and n-butanol. EtOAc fraction was fractionated using column chromatography and purified using preparative thin-layer chromatography (TLC). Isolates were studied for their antiplasmodial activity on parasites culture of chloroquine-sensitive 3D7 strain of Plasmodium falciparum. Parasitemia percentages, growth percentages, and inhibition percentages of each group were calculated. The half maximal inhibitory concentration (IC50) values that represent the concentration required to inhibit 50% of Plasmodium growth were calculated from a calibration curve using linear regression. The results suggest that isolates have antiplasmodial activity and are responsible in the antimalarial activity of Alectryon serratus leaves. Abbreviations Used: S.F: Subfraction, EGCG: Epigallocatechingallate, EGC: Epigallocatechin.

Inhibition of hepatitis C virus replication by chalepin and pseudane IX isolated from Ruta angustifolia leaves.

Hepatitis C virus (HCV) infection is highly prevalent among global populations, with an estimated number of infected patients being 170 million. Approximately 70-80% of patients acutely infected with HCV will progress to chronic liver disease, such as liver cirrhosis and hepatocellular carcinoma, which is a substantial cause of morbidity and mortality worldwide. New therapies for HCV infection have been developed, however, the therapeutic efficacies still need to be improved. Medicinal plants are promising sources for antivirals against HCV. A variety of plants have been tested and proven to be beneficial as antiviral drug candidates against HCV. In this study, we examined extracts, their subfractions and isolated compounds of Ruta angustifolia leaves for antiviral activities against HCV in cell culture. We isolated six compounds, chalepin, scopoletin, γ-fagarine, arborinine, kokusaginine and pseudane IX. Among them, chalepin and pseudane IX showed strong anti-HCV activities with 50% inhibitory concentration (IC50) of 1.7 ± 0.5 and 1.4 ± 0.2 µg/ml, respectively, without apparent cytotoxicity. Their anti-HCV activities were stronger than that of ribavirin (2.8 ± 0.4 µg/ml), which has been widely used for the treatment of HCV infection. Mode-of-action analyses revealed that chalepin and pseudane IX inhibited HCV at the post-entry step and decreased the levels of HCV RNA replication and viral protein synthesis. We also observed that arborinine, kokusaginine and γ-fagarine possessed moderate levels of anti-HCV activities with IC50 values being 6.4 ± 0.7, 6.4 ± 1.6 and 20.4 ± 0.4 µg/ml, respectively, whereas scopoletin did not exert significant anti-HCV activities at 30 µg/ml.

Flavonoids with antiplasmodial and cytotoxic activities of Macaranga triloba.

A new flavanone derivative, malaysianone A (1), four prenylated flavanones, 6-prenyl-3'-methoxyeriodictyol (2), nymphaeol B (3), nymphaeol C (4) and 6-farnesyl-3',4',5,7-tetrahydroxyflavanone (5), and two coumarins, 5,7-dihydroxycoumarin (6) and scopoletin (7), were isolated from the dichloromethane extract of the inflorescences of Macaranga triloba. The structures of these compounds were elucidated based on spectroscopic methods including nuclear magnetic resonance (NMR-1D and 2D), UV, IR and mass spectrometry. The cytotoxic activity of the compounds was tested against several cell lines, with 5 inhibiting very strongly the growth of HeLa and HL-60 cells (IC(50): 1.3 µg/ml and 3.3 µg/ml, respectively). Compound 5 also showed strong antiplasmodial activity (IC(50): 0.06 µM).

Melidianolic acid A and B, new antimalarial acyclic diterpenes from Aphanamixis grandifolia.

Two new acyclic diterpenes, melidianolic acids A (1) and B (2), have been isolated from the bark of Aphanamixis grandifolia. Their structures were elucidated on the basis of spectroscopic and chemical methods. Melidianolic acids A (1) and B (2) showed antimalarial activity against Plasmodium falciparum 3D7 with IC50 of 6.1 and 7.3 microg/mL, respectively.

Delaumonones A and B, new antiplasmodial quassinoids from Laumoniera bruceadelpha.

New quassinoids, delaumonones A (1) and B (2) have been isolated from the bark of Laumoniera bruceadelpha NOOTEBOOM (Simaroubaceae) and the structures were elucidated by 2D NMR analysis and a chemical correlation. Delaumonones showed an antimalarial activity against Plasmodium falciparum.

Sucutiniranes A and B, new cassane-type diterpenes from Bowdichia nitida.

Two new cassane-type diterpenes, sucutiniranes A (1) and B (2), have been isolated from the seeds of Bowdichia nitida together with 6alpha-acetoxyvouacapane (3) and 6alpha,7beta-diacetoxyvouacapane (4), and the structures of 1 and 2 were elucidated by using 2D NMR data and chemical correlations. Sucutinirane A (1) and 3 showed a moderate cytotoxicity against human colon carcinoma COLO201 cells, and 6alpha,7beta-diacetoxyvouacapane (4) showed in vitro antiplasmodial activity against parasite Plasmodium falciparum 3D7.

Apoptosis inducing effect of andrographolide on TD-47 human breast cancer cell line.

Andrographolide isolated from Andrographis paniculata Ness (Acanthaceae) at 0.35 mM, 0.70 mM and 1.40 mM induced DNA fragmentation and increased the percentage of apoptotic cells when TD-47 human breast cancer cell line was treated for 24, 48 and 72 h. The results demonstrated that andrographolide can induce apoptosis in TD-47 human breast cancer cell line in a time and concentration-dependent manner by increase expression of p53, bax, caspase-3 and decrease expression of bcl-2 determined by immunohistochemical analysis.