In VitroandIn VivoAntimalarial Activity of Essential Oils and Chemical Components from Three Medicinal Plants Found in Northeastern Brazil

Abstract

The prophylactic and therapeutic arsenal against malaria is quite restricted and all the antimalarials currently in use have limitations. Thus, there is a need to investigate medicinal plants in the search for phytochemicals which can be developed into drugs. In our investigation, essential oils (EOs) were obtained from Vanillosmopsis arborea (Gardner) Baker, Lippia sidoides Cham. and Croton zehntneri Pax & K. Hoffm., aromatic plants abundant in northeastern Brazil, which are found in the caatinga region and are used in traditional medicine. The chemical composition of these EOs was characterized by GC-MS, and monoterpenes and sesquiterpenes were well represented. We assessed the in vitro activity of these EOs and also individual EO chemical components against the human malaria parasite Plasmodium falciparum (K1 strain) and the in vivo activity of EOs in mice infected with Plasmodium berghei. The acute toxicity of these oils was assessed in healthy mice and in vitro cytotoxicity was determined at different concentrations against HeLa cells and mice macrophages. The EO of V. Arborea was partially active only when using the subcutaneous route (inhibited from 33 up to 47 %). In relation to the EOs, L. sidoides and C. zehntneri were active only by the oral route (per gavage) and partially inhibited the growth of P. berghei from 43 up to 55 % and showed good activity against P. falciparum in vitro (IC (50) = 7.00, 10.50, and 15.20 µg/mL, respectively). Individual EO constituents α-bisabolol, estragole, and thymol also exhibited good activity against P. falciparum (IC (50) = 5.00, 30.70, and 4.50 µg/mL, respectively). This is the first study showing evidence for the antimalarial activity of these species from northeastern Brazil and the low toxicity of their EOs.

In Vivo Antimalarial Activity and Mechanisms of Action of 4-Nerolidylcatechol Derivatives

“…The results are presented in Table 2. At 50 mg kg Ϫ1 day Ϫ1 , a dose often used to identify potential new drugs in murine malaria (42,43), compound 2 was considered partially active (44,45), as it suppressed P. berghei growth by Ͼ30% on days 5 and 7 for both routes of administration. At the highest dose (600 mg kg Ϫ1 day Ϫ1 ), subcutaneous and oral administration of compound 2 led to 72 and 64% suppression of parasitemia, respectively, on the fifth day after treatment began.…”

ATIVIDADE OVICIDA DO ÓLEO ESSENCIAL E DO EXTRATO HIDROALCOÓLICO DE Ocimum basilicum SOBRE NEMATÓDEOS GASTRINTESTINAIS DE OVINOS

“…Estudos avaliando seu potencial de uso no controle de protozoários (ALMEIDA et al, 2007;MOTA et al, 2012), fungos (DAMBOLENA et al, 2010), insetos (GHOSH et al, 2012) basilicum, para isso, foram pesados 100 g da planta e adicionados 1000 mL de solução alcoólica a 70% e posteriormente esta mistura foi acondicionada ao abrigo da luz sob agitação diária durante sete dias. A seguir realizou-se a filtragem, obtendo-se 760 mL da tintura, a qual foi acrescentado 240 mL de álcool 70%.…”

Antioxidant activity of Matricaria chamomilla L. extract and clinical efficacy of cosmetic formulations containing this extract and its isolated compounds

“…O extracto de Matricaria chamomilla L. é rico em flavonoides, terpenos, polissacarídeos, entre outros, que podem fornecer para as formulações propriedades bioactivas, tais como efeitos anti--inflamatório e emoliente (6,7,8). O composto isolado a partir de extracto de camomila α-bisabolol foi avaliado como tendo actividades antimicrobianas (9), anti-inflamatórias (10), anti-nociceptivas (10) e antimaláricas (11). A apigenina, outro composto isolado a partir de extracto de camomila, tem sido citado na literatura como protetor dos queratinócitos da pele quando submetidos a ação de Espécies Reativas de Oxigênio (EROs) induzidas pela radição ultravioleta-B e danos ao DNA (12).…”