Constituintes químicos de Capraria biflora (Scrophulariaceae) e atividade larvicida de seu óleo essencial

Analysis of essential oil from fresh leaves of Capraria biflora allowed identification of fourteen essential oil constituents among which thirteen are sesquiterpene compounds, and α-humulene (43.0%) the major constituent. The essential oil was tested for larvicidal activity against Aedes aegypti showing good activity, with LC50 73.39 µg/mL (2.27 g/mL). Chromatographic studies of extracts from roots and stems allowed the isolation of five compounds: naphthoquinone biflorin, sesquiterpene caprariolide B, the steroid β-sitosterol, the carbohydrate D-mannitol and iridoid myopochlorin first reported in the species C. biflora. The structures of compounds were characterized by spectroscopic data, IR, MS, NMR13C, NMR¹H, NOE, HSQC and HMBC.

Isolamento do verbacosídeo e validação de método analítico para padronização do extrato bruto das partes aéreas de Buddleja stachyoides Cham. & Schltdl. (Scrophulariaceae)

Phenylpropanoid glycoside verbascoside was isolated and identified from the ethyl acetate fraction of the aerial parts of Buddleja stachyoides Cham. & Schltdl. by 1H-NMR. A method using high-performance liquid chromatography has been developed and validated for determination of verbascoside in alcoholic crude extract of the aerial parts of B. stachyoides. Analysis was performed on a Phenomenex® Gemini-NX C18 analytical column (250 mm × 4.6 mm; 5 µm) using a mobile phase (pump A - aqueous solution containing H2SO4 (0.01 M), H3PO4 (0.4%), and (C2H5)2NH (0.4%); pump B - methanol:aqueous (95:5) solution containing H2SO4 (0.05 M), H3PO4 (2%), and (C2H5)2NH (0.2%); pump C - acetonitrile:aqueous (90:10) solution containing H2SO4 (0.05 M) and H3PO4 (2%)) and a diode array detector at 325 nm. The method was validated in accordance with ANVISA guidelines and may be applied to quality control of herbal medicine with aerial parts of B. stachyoides.

Preliminary assessment of medicinal plants used as antimalarials in the southeastern Venezuelan Amazon

Eighteen species of medicinal plants used in the treatment of malaria in Bolívar State, Venezuela were recorded and they belonged to Compositae, Meliaceae, Anacardiaceae, Bixaceae, Boraginaceae, Caricaceae, Cucurbitaceae, Euphorbiaceae, Leguminosae, Myrtaceae, Phytolaccaceae, Plantaginaceae, Scrophulariaceae, Solanaceae and Verbenaceae families. Antimalarial plant activities have been linked to a range of compounds including anthroquinones, berberine, flavonoids, limonoids, naphthquinones, sesquiterpenes, quassinoids, indol and quinoline alkaloids.

Phytochemical study, antioxidant and antibacterial activities of Stemodia maritima

Stemodinol, a new natural compound, together with known compounds including jaceidin, stemodin, stemodinoside B, isocrenatoside, verbascoside, crenatoside, and isoverbascoside, were isolated from Stemodia maritima Linn. The antioxidant (DPPH method) and antimicrobial activities of stemodin, stemodinoside B, and crenatoside were investigated. Among the components tested, only crenatoside isolated from the roots showed a high antioxidant power. Stemodin and stemodinoside B exhibited antibacterial activities.