Antitumor and Antiviral Activity of Colombian Medicinal Plant Extracts

Abstract

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 49.6x10(3)mg/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

“…One of these methods is EPTT (Vlietinck et al 1995) and the other is a bioassay based on the metabolic reduction of MTT (Mosmann 1983, Denizot & Lang 1986, Betancur-Galvis et al 1999, so as to evaluate both the antiviral and antitumour activity. The selection of the Euphorbia genus plant species for the present study was mainly based on the common use of these species for the treatment of various diseases, as indicated by traditional Colombian healers (Garcia-Barriga 1974, Perez 1975, Vasquez 1982, Piñeros et al 1992.…”

“…Indeed, the bis-tetrahydrofuran acetogenin membrarollin isolated from R. membranacea, appears to be a very potent inhibitor of the NADH oxidase activity (Degli Esposti et al 1994, Zafra-Polo et al 1996. For this reason, the cytotoxic activity of the species R. membranacea has served here as a positive control (Betancur-Galvis et al 1999) in experiments aimed at finding the antitumour potential of our extracts.…”

“…Ten infectious doses of virus were added to each well and incubated at 37°C in humidified 5% CO 2 atmosphere for 48 h. Controls consisted of untreated infected, treated uninfected and untreated uninfected cells. Furthermore all tests were compared with a positive control, Acyclovir (Quiviral, Laboratorios Quibi, Santafé de Bogotá-Colombia), and tested simultaneously under identical conditions as reported previously (Betancur-Galvis et al 1999). Cell viability was evaluated by the MTT colorimetric technique (Mosmann 1983).…”

The good and the bad: Alkaloid screening and brineshrimp bioassays of aqueous extracts of 31 medicinal plants of eastern Nicaragua

“…The effectiveness of these two species as herbal remedies may be due to the presence of other types of secondary metabolites such as flavanoids, glycosides, phenols, sapogenins, saponins, and tannins (Heltzel et al, 1993a(Heltzel et al, , 1993bBinutu & Lajubutu, 1994;Kaneko et al, 1997Kaneko et al, , 1998Betancur-Galvis et al, 1999;Bystrom et al, 2008;Ogbuagu, 2008). For example, the fruit pulp of C. cujete contains flavanoids, saponins, cyanogenic glycosides (as HCN), phenols, and tannins (Ogbuagu, 2008).…”

Potential Antivirals: Natural Products Targeting Replication Enzymes of Dengue and Chikungunya Viruses

“…According to a WHO factsheet, 80% of the population of certain Asian and African countries depend on traditional medicines for primary health care due to economic and geographic constraints [16,[22][23][24][25]. Because of their few (or unknown) adverse effects, the global use of medicinal plants or herbal-based medicines is steadily growing.…”