Antiprotozoal screening of the Cuban native plant Scutellaria havanensis

Abstract

Context: Scutellaria havanensis Jacq. (Lamiaceae) is a native medicinal herb with a history of use in Cuba.Objective: This study screens the antiprotozoal activity of S. havanensis. Materials and methods: Chloroform and methanol extracts from leaves and stems were evaluated in vitro at doses between 0.015 and 200 lg/mL against protozoan parasites: Plasmodium berghei, Trichomonas vaginalis and Leishmania amazonensis. Chloroform and methanol extracts were characterized by GC/MS. Cytotoxicity against mouse peritoneal macrophages was tested in parallel. Results: Scutellaria havanensis extracts exhibited IC 50 values between 7.7 and 32.2 lg/mL against trophozoites of P. berghei and T. vaginalis; while the extracts were inactive against L. amazonensis promastigotes. Trichomonicidal activity of methanol extract exhibited the best selectivity but chloroform extract showed the highest antiplasmodial, trichomonicidal and cytotoxic activity. The majority of compounds in the chloroform extract were hydroxy and/or methoxyflavones (77.96%), in particular, wogonin (48.27%). In methanol extract, wogonin (5.89%) was detected. Trichomonicidal effect of wogonin was moderate (IC 50 ¼ 56 lM) and unspecific with respect to macrophages (SI ¼ 2). On the contrary, antiplasmodial activity of wogonin were particularly active (IC 50 ¼ 15 lM) demonstrating a higher selectivity index (SI ¼ 7.4). Conclusions: Wogonin is an active principle compound of the chloroform extract of S. havanensis against P. berghei and T. vaginalis trophozoites, whereas the methanol extract of S. havanensis should be investigated more deeply as a trichomonicide. Our findings suggest that wogonin is potentially useful for the development of antimalarial alternative treatments. ARTICLE HISTORY

Actividad antibacteriana, determinación de polifenoles totales por Folin-Ciocalteu y toxicidad en Artemia salina de la especie vegetal Bauhinia variegata

“…El grado de toxicidad del extracto se definió en fun-ción del rango en que se encontró el valor de CL50 de acuerdo con las categorías siguientes: extremadamente tóxico (CL50< 10 µg/mL), muy tóxico (10< CL50 <100), moderadamente tóxico (100< CL50 <1 000) y no tóxico (CL50> 1 000 µg/mL). 23 Por lo tanto, el extracto polar de B. variegata se considera no tóxico.…”

Micropropagation of Rare Scutellaria havanensis Jacq. and Preliminary Studies on Antioxidant Capacity and Anti-Cancer Potential

“…The methanol and chloroform extracts of S. havanensis leaves and stems contain high concentrations of flavonoids including bioactive wogonin. Wogonin in the chloroform extract indicated its specific anti-plasmodial effect with respect to mammalian cells and thus could be useful for the development of antimalarial alternatives [25]. These compounds are synthesized in glandular trichomes that serve the function of defense and source of valuable chemicals and are also used as taxonomic tools.…”

Anti-trichomonad activities of different compounds from foods, marine products, and medicinal plants: a review

“…Fernández-Calienes Valdés, Monzote Fidalgo [ 32 ] found that extracts of leaves and stems of Scutellaria havanensis , a plant native to Cuba, and the isolated flavonoid compound wogonin (Fig. 2 ) exhibited anti-trichomonad activity against T. vaginalis with the following selectivity indices: methanol extract 7.3; chloroform extract 2.8; wogonin 2.0; and metronidazole 322.6.…”