Maria Goretti de Vasconcelos Silva

Atividade larvicida de óleos essenciais contra Aedes aegypti L. (Diptera: Culicidae)

In the search for alternative chemical control against Aedes aegypti L., many researches are developed and encouraged in order to find new insecticidal plant substances. In this work, the larvicidal effect of ten essential oils was tested on A. aegypti. The oils were extracted by steam distillation and their chemical composition determined by GL-chromatography coupled with mass spectroscopy. The essential oils were diluted in aqueous solutions of dimethyl sulfoxide with concentrations of: 100, 50, 10, and 1 mg/ml. The larvicidal activity, based on the percentage of larval mortality, was evaluated after 24h exposure to the treatments. The essential oil of Vanillosmopsis arborea Baker presented the highest larvicidal activity, with CL50 of 15.9 mg/ml and CL90 of 28.5 mg/ml. On the other hand the essential oil of O.gratissimum L. showed the lower activity with CL50 de 95,80 mg/ml and CL90 de 102,86 mg/ml.The results indicate that the tested essential oils, and particularly the V. arborea, are composed by substances with larvicidal properties for A. aegypti.

Medicinal Plants of Northeast Brazil Containing Thymol and Carvacrol - Lippia sidoides Cham. and L. gracillis H.B.K. (Verbenaceae)

Abstract Lippia sidoides Cham, and L. gracillis H.B.K. (Verbenaceae) are wild aromatic small trees or shrubs of Northeast Brazil vegetation. Chemical analysis of the oils obtained from the two plants by GC/MS revealed that L. sidoides contained thymol (73.1%), while L. gracillis contained carvacrol (47.7%) and p-cymene (19.2%) as main components.

Gastroprotective effect of barbatusin and 3-beta-hydroxy-3-deoxibarbatusin, quinonoid diterpenes isolated from Plectranthus grandis, in ethanol-induced gastric lesions in mice.

ETHNOPHARMACOLOGICAL RELEVANCE Validate the popular use of Plectranthus grandis in gastric disorders through the active components. AIMS Isolation of barbatusin (BB) and 3beta-hydroxy-3-deoxibarbatusin (BBOH), diterpenes from Plectranthus grandis, and evaluation of their gastroprotective effect and possible mechanisms of action. MATERIALS AND METHODS Isolation and chemical characterization of diterpenes from Plectranthus grandis by chromatographic and spectroscopic methods and evaluation of gastroprotective action of the diterpenes through ethanol-induced gastric injury in mice model. It was evaluated the effect of capsazepine, indomethacin and the role of nitric oxide and K(ATP-) channels on the gastroprotective effect of BBOH and BB. Additionally it was measured the concentrations of gastric mucus, non-proteic-sulfhydryl groups and total thiobarbituric acid-reactive substances. RESULTS Orally administered BBOH and BB at doses of 5 and 10mg/kg, markedly reduced the gastric lesions by 59 and 96%, and 32 and 76%, respectively, with superior results as compared to N-acetylcysteine (150 mg/kg, i.p.), reference compound that caused 85% lesion suppression. Although BBOH presented a higher gastroprotection than BB they act by similar mechanisms in relation to N-acetylcysteine, and prevent the depletion of gastric mucus, gastric mucosal non-proteic-sulfhydryl groups as well as the increase in thiobarbituric acid-reactive species. Moreover, the gastroprotective effect of BB was effectively blocked in mice pretreated with TRPV1 antagonist capsazepine, by the non-selective cyclooxygenase inhibitor indomethacin, or by the nitric oxide synthase inhibitor L-NAME but not by K(+)(ATP) channel inhibitor glibenclamide. In contrast, the gastroprotective effect of BBOH was blocked only by indomethacin and glibenclamide pretreatments. CONCLUSION The protective role for BBOH and BB affording gastroprotection against gastric damage induced by ethanol indicates that these compounds contribute for the activity of Plectranthus species. The different modes of action are probably related to differences in their chemical structure.

Evaluation of central nervous system effects of iso-6-cassine isolated from Senna spectabilis var. excelsa (Schrad) in mice

The depressant and anticonvulsant activities of iso-6-cassine (ISO) from Senna spectabilis (0.5, 1.0 and 1.5mg/kg) injected by oral route in mice caused a significant decrease in the motor activity of animals when compared with the control group, up to 30 days after the administration and at dose of 1.5mg/kg, it reduced the remaining time of animals on Rota-rod apparatus. Additionally, ISO at doses tested was also capable to promote an increase of latency for development of convulsions induced by pentylenetetrazole and picrotoxin. These results suggest possible depressant and anticonvulsant activities in mice that need further investigation.

Volatile Constituents from Leaves and Inflorescence Oil of Ocimum tenuiflorum L. f. (syn. O. sanctum L.) Grown in Northeastern Brazil

Abstract Ocimum tenuiflorum L.f. (syn O. sanctum L.) (Labiatae) is an ayurvedic medicinal plant from India that was introduced in Northeastern Brazil in 1970. Oils produced by steam distillation and microwave distillation from leaves and inflorescences were analyzed by GC/MS and retention indices. The leaf oil contained eugenol (79.0–82.7%) and β-caryophyllene (7.9–9.8%) as major constituents, whereas the inflorescence oil was rich in eugenol (17.6–60.0%), β-caryophyllene (24.5–40.7%) and caryophyllene oxide (5.9–18.5%).

Volatile Constituents of Two Wedelia Species

ABSTRACT The essential oils obtained from the leaves of Wedelia paludosa DC. and Wedelia trilobata (L.) Hitch., were analyzed by GC/MS. α-Pinene was the chief constituent found in all samples of both oils in a yield above 30%. W. paludosa oil was also rich in β-pinene (10.3%), limonene (21.3%) and γ-muurolene (11.8%), while α-phellandrene (17.4%) and limonene (16.3%) were the other major components of W. trilobata oil.

The Presence of Indole as Minor Constituent of Tagetes erecta Leaf Oil

ABSTRACT Twenty-seven compounds have been characterized by GC/MS and Kovats indices in the essential oil of Tagetes erecta L. (Compositae). The major compounds are terpinolene (12.4%), (E)-β-ocimene (13.1%), piperitone (20.0%) and limonene (11.0%). The presence of indole among the minor compounds is somewhat surprising, since it was not reported before in this genus.

Characterization of the Industrial Residues of Seven Fruits and Prospection of Their Potential Application as Food Supplements

Seven residues from tropical fruit (acerola, cashew apple, guava, mango, papaya, pineapple, and sapota) processing were prospected for physicochemical parameters (pH, total soluble solids, water activity, reducing sugar, acidity, protein, moisture, ash, and lipids), functional compounds (total phenolic content, anthocyanins, ascorbic acid, and free radical scavenging activity—DPPH), fatty acid profile, and mineral content. Prospection of these industrial residues aimed its use as potential sources for food supplementation. Acerola residue was found to be a valuable source of anthocyanins, phenolics, and vitamin C; cashew apple residue could be a source of unsaturated fatty acids; pineapple and papaya residues could be used, respectively, as manganese and phosphorous source.

Essential Oil Composition of the Leaves of Ocimum micranthum Willd.

Abstract Variation on chemical composition of essential oils produced from Ocimum micranthum Willd. obtained from plants growing in northeast Brazil, at different stages of development and throughout the day. The oils, which were obtained by microwave oven distillation, were analyzed by GC/MS. A discreet variation in the eugenol contents from 97% at 6:00 a.m. to 84% at 6:00 p.m. was observed. The highest value was found in oil obtained from a specimen with a fully developed inflorescence. The eugenol production in O. micranthum does not appear to be influenced by solar light throughout the day.

Diterpenos tipo abietano isolados de Plectranthus barbatus Andrews

Plectranthus barbatus is largely used in the Northeast region of Brazil by the local population for treatment of digestive problems as substitute of boldo (Pneumus boldus). Phytochemical analysis of the leaf extracts of Plectranthus barbatus (Labiatae) cultivated in this region yielded two abietane diterpenoids, cyclobubatusin (1) and barbatusin (2) and a new one named 7b-acetyl-12-deacetoxycyclobutatusin (3). The structures of the isolated compounds were established by spectral analysis, using mainly mass spectra and 1H and 13CNMR (1D and 2D). These procedures permitted the assignment of all chemical shifts in the diterpenoids.