No abstract

No abstract

This study tested in vitro activity of the essential oil from flowers of Calendula officinalis using diskdiffusion techniques. The antifungal assay results showed for the first time that the essential oil has good potential antifungal activity: it was effective against all 23 clinical fungi strains tested.

Terpenes and aroma volatiles from flowers of Calendula officinalis cultivated in southeastern Brazil were obtained by steam distillation (SD), headspace-cold finger (HS-CF) extraction and headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography and mass spectrometric analysis. The dried flowers contained 0.1% oil. Kovats indices and mass spectra were used to identify 27 individual components in the various volatile fractions. The main components present in the volatile fractions of the C. officinalis flowers, obtained by SD, HS-SPME, and HS- CF, 22.1, 25.4, and 24.9 %) while 20.4 % of α-cadinol was seen only after SD extraction.

Free and bound volatile components of a Brazilian cashew apple variety (Anacardium occidentale L. var. nanum) were obtained by simultaneous distillation-extraction (SDE) and XAD-2 adsorption. According to gas chromatography-mass spectrometry (GC-MS) analyses and retention indices, 62 free volatile constituents were characterized and quantified. They were esters (40%), terpenes (20%), hydrocarbons (14%), fatty acids (9%), aldehydes (8%), alcohols (3%), lactones (3%), ketones (1%), phenols (1%), and norisoprenoids (1%). The glycosidically bound volatile precursors were analyzed by high-temperature GC-MS, after room temperature silylation. Several conjugated alcohols and cinnamic acids were detected and reported as cashew apple glycosyl constituents for the first time.

O uso de cromatografia sob pressão ("flash chromatography") utilizando-se coluna de gel de sílica impregnada com hidróxido de potássio levou ao fracionamento dos constituintes químicos de Copaifera cearensis Huber ex Ducke. A fração ácida, após esterificação com diazometano, foi analisada por cromatografia gasosa de alta resolução acoplada à espectrometria de massas ou à espectrometria no infravermelho, possibilitando a identificação de onze diterpenos ácidos. Fracionamentos adicionais da fração ácida por cromatografia líquida de alta eficiência em fase reversa levaram ao isolamento de diversos ácidos diterpênicos e de um sesquiterpênico que foram identificados através de seus dados espectroscópicos. A análise da sílica impregnada com hidróxido de potássio mostrou que, além da deposição do hidróxido na superfície da sílica, ocorreu troca iônica com formação de resíduos Si-OK.Various acid diterpenes of Copaifera cearensis Huber ex Ducke were isolated from the crude extract by flash Silica Gel/Potassium Hydroxide Chromatography. The main components were identified by GC-MS analyses. Further fractionation by reversed phase (RP) semi-preparative HPLC allowed isolation and identification of minor components and provided additional spectral data of those compounds. It was possible to detect the presence of eleven acid diterpenes in addition to a sesquiterpene acid. In addition to potassium hydroxide deposition on the silica surface, the presence of Si-OK residues, resulting from a cation exchange process, was established.

No abstract

Tetradenia riparia (Lamiaceae) is a well-known herbal medicine with a variety of useful properties, including its acaricidal effect. This experiment was carried out to study the bioacaricidal activity of T. riparia essential oil (EO) against engorged females of Rhipicephalus (Boophilus) microplus (Acari; Ixodidae). For this purpose, nine serial concentrations (12.50%, 6.25%, 3.75%, 1.80%, 0.90%, 0.45%, 0.22%, 0.11%, and 0.056% w/v) of T. riparia were used for the adult immersion test (AIT). For the larval packet test (LPT), we used 14 serial concentrations (100.00%, 50.00%, 25.00%, 12.50%, 6.25%, 3.65%, 1.82%, 0.91%, 0.45%, 0.228%, 0.114%, 0.057%, 0.028%, and 0.014% w/v). The results for AIT showed 100.00% and 2.05% mortality, 19.00 and 90.20% for the total number of eggs, egg-laying inhibition of 0.00% and 90.20%, hatchability inhibition of 0.00% and 70.23%, and product effectiveness of 100.00% and 2.89%, respectively. The AIT indicated that the LC(50) and LC(99.9), calculated using the Probit test, were for mortality (%) 0.534g/mL (0.436-0.632) and 1.552g/mL (1.183-1.92); for total number of eggs were 0.449g/mL (0.339-0.558) and 1.76g/mL (1.27-2.248); and for hatchability inhibition were 0.114g/mL (0.0-0.31) and 2.462g/mL (1.501-3.422), respectively. Larvae between 14 and 21days old were fasted and placed in each envelope. Bioassays were performed at 27°±1°C, RH⩾80%. Larval mortality was observed 24h after treatment and showed 10.60-100% mortality in the LPT bioassay. The LPT showed that the LC(50) and LC(99.9) were 1.222g/mL (0.655-1.788) and 11.382g/mL (7.84-14.91), respectively. A positive correlation between T. riparia EO concentration and tick control, was observed by the strong acaricidal effects against R. (B.) microplus, and the mortality rate of ticks was dose-dependent. Our results showed that T. riparia is a promising candidate as an acaricide against resistant strains of R. (B.) microplus.