Antitumor and Antiviral Activity of Colombian Medicinal Plant Extracts

Extracts of nine species of plants traditionally used in Colombia for the treatment of a variety of diseases were tested in vitro for their potential antitumor (cytotoxicity) and antiherpetic activity. MTT (Tetrazolium blue) and Neutral Red colorimetric assays were used to evaluate the reduction of viability of cell cultures in presence and absence of the extracts. MTT was also used to evaluate the effects of the extracts on the lytic activity of herpes simplex virus type 2 (HSV-2). The 50% cytotoxic concentration (CC50) and the 50% inhibitory concentration of the viral effect (EC50) for each extract were calculated by linear regression analysis. Extracts from Annona muricata, A. cherimolia and Rollinia membranacea, known for their cytotoxicity were used as positive controls. Likewise, acyclovir and heparin were used as positive controls of antiherpetic activity. Methanolic extract from Annona sp. on HEp-2 cells presented a CC50 value at 72 hr of 49.6x103μg/ml. Neither of the other extracts examined showed a significant cytotoxicity. The aqueous extract from Beta vulgaris, the ethanol extract from Callisia grasilis and the methanol extract Annona sp. showed some antiherpetic activity with acceptable therapeutic indexes (the ratio of CC50 to EC50). These species are good candidates for further activity-monitored fractionation to identify active principles

Cytotoxic and Antiviral Activities of Colombian Medicinal Plant Extracts of the Euphorbia genus

Forty-seven plant extracts of 10 species of the genus Euphorbia   ( Euphorbia ceae) used by Colombian traditional healers for the treatment of ulcers, cancers, tumors, warts, and other diseases, were tested in vitro for their potential antitumour (antiproliferative and cytotoxic) and antiherpetic activity. To evaluate the capacity of the extracts to inhibit the lytic activity of herpes simplex virus type 2 (HSV-2) and the reduction of viability of infected or uninfected cell cultures, the end-point titration technique (EPTT) and the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] colorimetric assay were used, respectively. The therapeutic index of the positive extracts for the antiviral activity was determined by calculating the ratio CC 50 (50% cytotoxic concentration) over IC 50 (50% inhibitory concentration of the viral effect). Five of the 47 extracts (11%) representing 3 out of 10 Euphorbia species (30%) exhibited antiherpetic action; the highest activity was found in the leaf/stem water-methanol extracts from E. cotinifolia   and E. tirucalli   . The therapeutic indexes of these two plant species were > 7.1; these extracts exhibited no cytotoxicity. Six extracts (13%) representing 4 plant species (40%) showed cytotoxic activity. The highest cytotoxicity was found in the dichloromethane extract obtained from E. cotinifolia leaves and the CC 50 values for the most susceptible cell lines, HEp-2 and CHO, were 35.1 and 18.1 mg/ml, respectively

Terretonins E and F, Inhibitors of the Mitochondrial Respiratory Chain from the Marine-Derived Fungus Aspergillus insuetus

Supporting Information Available: 1D and 2D NMR spectra for terretonins E and F. This material is available free of charge via the Internet at http://pubs.acs.org.[EN] Two new meroterpenoids, terretonins E and F (1, 2), together with three known compounds, aurantiamine (3), linoleic acid, and uridine, were isolated as fermentation products of the marine-derived fungus Aspergillus insuetus, which was associated with the sponge Petrosia ficiformis. Structures of all isolates were elucidated employing spectroscopic methods, mainly by two-dimensional NMR techniques. Compounds 1-3 showed activity as inhibitors of the mammalian mitochondrial respiratory chain.We acknowledge ICB and ITQ NMR Service (D. Melck and E. Mateos) and E. Estornell and V. Romero for biological assay support. We would like to thank the R&D&I Linguistic Assistance Office, Universidad Politecnica de Valencia (Spain), for granting financial support for the linguistic revision of this paper. This work has been supported through European Social Fund (ESF).López Gresa, MP.; Cabedo Escrig, N.; Gonzalez-Mas, MC.; Ciavatta, ML.; Avila, C.; Primo Millo, J. (2009). Terretonins E and F, Inhibitors of the Mitochondrial Respiratory Chain from the Marine-Derived Fungus Aspergillus insuetus. Journal of Natural Products. 72(7):1348-1351. doi:10.1021/np900085nS1348135172

A mutagenicity and cytotoxicity study on Limonium effusum aqueous extracts by Allium, Ames and MTT tests

Nowadays plants or plant extracts have become very important for alternative medicine. Plants and their extracts have many therapeutical advantages but some of them are potentially toxic, mutagenic, carcinogenic and teratogenic. Root, stem and leaf parts of Limonium effusum were used in this study and this species is an endemic species for Turkey. Mutagenic and cytotoxic effects of root, stem and leaf aqueous extracts were observed with Allium, Ames and MTT tests. Allium root growth inhibition test and mitotic index studies showed that aqueous extracts have dose-dependent toxic effects. Chromosome aberration studies indicated that especially sticky chromosome, anaphase-telophase disorder and laggard chromosome anomalies were highly observed. Ames test performed with Limonium effusum root aqueous extracts, showed weak mutagenic effects in Salmonella typhimurium TA98 strain with S9. MTT test based on mitochondrial activity indicated that most of the aqueous extracts have cytotoxic effects. This study aimed to determine the possible mutagenic and cytotoxic effects of L. effusum aqueous extracts by using bacterial, plant and mammalian cells. This research showed that some low concentrations of the L. effusum extracts have inhibited cytotoxic effects but high concentrations have induced cytotoxicity. On the other hand only a weak mutagenic activity was identified by Ames test with TA98 S9(+).В настоящее время растения или экстракты растений стали очень важными для альтернативной медицины. Растения и их экстракты имеют много терапевтических преимуществ, однако некоторые из них являются потенциально токсичными, мутагенными, канцерогенными и тератогенными. Корни, стебли и листья Limonium effusum, эндемичного вида Турции, были изучены в этой работе. Мутагенные и цитотоксические эффекты водных экс-трактов корней, стеблей и листьев Limonium effusum были изучены с помощью Allium-теста, теста Эймса и МТТ-теста. Тест на ингибирование роста корней лука и определение митотического индекса показали, что водные экстракты имеют дозозависимый токсичный эффект. При изучении хромосомных аберраций обнаружено большое количество таких аномалий, как слипшиеся хромосомы, нарушения анафазы-телофазы и отставшие хромосомы. Тест Эймса, проведенный на водных экстрактах корней Limonium effusum, показал слабо выраженный мутагенный эффект по отношению к Salmonella typhimurium, штамм TA98 с S9. МТТ-тест, основанный на митохондриальной активности, показал, что большинство экстрактов имели цитотоксические эффекты. Цель этого исследования изучить возможные мутагенные и цитотоксические эффекты водных экстрактов L. effusum с использованием бактериальных, растительных клеток и клеток млекопитающих. Определенные низкие концентрации экстрактов L. effusum ингибировали цитотоксические эффекты, а высокие концентрации индуцировали цитотоксичность. Слабая мутагенная активность была определена только при помощи теста Эймса с TA98 S9(+)

Cytotoxicity and potential antiviral evaluation of violacein produced by Chromobacterium violaceum

Natural products are an inexhaustible source of compounds with promising pharmacological activities including antiviral action. Violacein, the major pigment produced by Chromobacterium violaceum, has been shown to have antibiotic, antitumoral and anti-Trypanosoma cruzi activities. The goal of the present work was to evaluate the cytotoxicity of violacein and also its potential antiviral properties.The cytotoxicity of violacein was investigated by three methods: cell morphology evaluation by inverted light microscopy and cell viability tests using the Trypan blue dye exclusion method and the MTT assay. The cytotoxic concentration values which cause destruction in 50% of the monolayer cells (CC50) were different depending on the sensitivity of the method. CC50 values were > 2.07 ± 0.08 µM for FRhK-4 cells: > 2.23 ± 0.11 µM for Vero cells; > 2.54 ± 0.18 µM for MA104 cells; and > 2.70 ± 0.20 µM for HEp-2 cells. Violacein showed no cytopathic inhibition of the following viruses: herpes simplex virus type 1 (HSV-1) strain 29-R/acyclovir resistant, hepatitis A virus (strains HM175 and HAF-203) and adenovirus type 5 nor did it show any antiviral activity in the MTT assay. However violacein did show a weak inhibition of viral replication: 1.42 ± 0.68%, 14.48 ± 5.06% and 21.47 ± 3.74% for HSV-1 (strain KOS); 5.96 ± 2.51%, 8.75 ± 3.08% and 17.75 ± 5.19% for HSV-1 (strain ATCC/VR-733); 5.13 ± 2.38 %, 8.18 ± 1.11% and 8.51 ± 1.94% for poliovirus type 2; 8.30 ± 4.24%; 13.33 ± 4.66% and 24.27 ± 2.18% for simian rotavirus SA11, at 0.312, 0.625 and 1.250 mM, respectively, when measured by the MTT assay