Manoel Andrade Neto

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.

Antibacterial activity of GUAVA, Psidium guajava Linnaeus, leaf extracts on diarrhea-causing enteric bacteria isolated from Seabob shrimp, Xiphopenaeus kroyeri (Heller)

O cha de folhas de goiaba Psidium guajava Linnaeus e comumente usado como remedio nas gastrenterites e diarreias infantis por aqueles que nao tem acesso a antibioticos. Esta pesquisa estudou o efeito antibacteriano sobre bacterias causadoras de diarreias, do oleo essencial e do extrato de folhas de goiabeira usando como diluente: metanol, hexano e acetato de etila. Os extratos foram testados sobre Staphylococcus aureus, Salmonella spp. e Escherichia coli. As bacterias testadas foram isoladas de camarao sete-barbas Xiphopenaeus kroyeri (Heller) usando-se como controle cepas padrao, de cada especie. Das bacterias testadas, o melhor efeito inibitorio foi observado sobre Staphylococcus aureus. O extrato de metanol apresentou maior inibicao bacteriana. O oleo essencial mostrou acao inibitoria contra S. aureus e Salmonella spp. Foi demonstrada alguma resistencia das cepas isoladas de camarao aos antibioticos comerciais testados. Estes dados confirmam que remedios a base de folhas de goiabeira podem ser utilizados em casos de diarreia provocada por essas bacterias, quando o uso de antibiotico for restrito. Conclui-se que extratos de folhas de goiaba e o seu oleo essencial sao muito ativos contra S. aureus, tornando-os importantes fontes em potencial de novos compostos antimicrobianos.Guava leaf tea of Psidium guajava Linnaeus is commonly used as a medicine against gastroenteritis and child diarrhea by those who cannot afford or do not have access to antibiotics. This study screened the antimicrobial effect of essential oils and methanol, hexane, ethyl acetate extracts from guava leaves. The extracts were tested against diarrhea-causing bacteria: Staphylococcus aureus, Salmonella spp. and Escherichia coli. Strains that were screened included isolates from seabob shrimp, Xiphopenaeus kroyeri (Heller) and laboratory-type strains. Of the bacteria tested, Staphylococcus aureus strains were most inhibited by the extracts. The methanol extract showed greatest bacterial inhibition. No statistically significant differences were observed between the tested extract concentrations and their effect. The essential oil extract showed inhibitory activity against S. aureus and Salmonella spp. The strains isolated from the shrimp showed some resistance to commercially available antibiotics. These data support the use of guava leaf-made medicines in diarrhea cases where access to commercial antibiotics is restricted. In conclusion, guava leaf extracts and essential oil are very active against S. aureus, thus making up important potential sources of new antimicrobial compounds.

Central effects of isolated fractions from the root of Petiveria alliacea L. (tipi) in mice

ETHNOPHARMACOLOGICAL RELEVANCE Petiveria alliacea L. (tipi) a shrub from Phytolaccaceae family is popularly used in folk medicine for treating a wide variety of disorders in South and Central America. AIM OF THE STUDY To investigate the neuropharmacological properties on experimental animals. MATERIALS AND METHODS The acetate (FA), hexanic (FH), hydroalcoholic (FHA) and precipitated hydroalcoholic (FHAppt) fractions from the root of tipi were studied to investigate its pharmacological properties in the classical behavioral models (open-field, elevated plus maze-EPM, rotarod, barbiturate-induced sleeping time, forced swimming and pentylenetetrazole (PTZ)-induced convulsions tests) using mice. These fractions were administered intraperitoneally and orally to female mice at single doses of 100 and 200mg/kg. RESULTS All these fractions decreased the locomotor activity, rearing and grooming in the open-field test, suggesting a possible central depressant action. No significant effect was evident on motor coordination of the animals in the rotarod test. On EPM, all the fractions of tipi presented a significant reduction on the time of permanence in the open arms, indicating an absence of anxiolytic-like effect. In addition, the fractions increased the immobility time in the forced swimming test and potentiated pentobarbital-induced sleeping time in mice, confirmed a probable sedative and central depressant effect. Furthermore, the fractions increased the latency to the first convulsion and the lethal time of the PTZ-induced convulsions test in the animals, confirmed its popular use as anticonvulsant. CONCLUSION Our results suggest that the fractions of P. alliacea L. contains biologically active substance(s) that might be acting in the CNS and have significant depressant and anticonvulsant potentials, supporting folk medicine use of this plant.

Effect of anxiolytic, antidepressant, and antipsychotic drugs on cocaine-induced seizures and mortality.

Cocaine abuse may lead to overdose (related to seizures and/or status epilepticus) and to diseases (schizophrenia, depression, and anxiety). This work was designed to study the influence of drugs used to treat psychopathologies associated with cocaine abuse on cocaine-induced seizures and mortality in mice. Fluoxetine (10, 20, 40 mg/kg), imipramine and buspirone (5, 10 mg/kg), pimozide (10, 20 mg/kg), lithium (56.3, 112.5 mg/kg), and naltrexone (25, 50 mg/kg) were administered intraperitoneally, 30 minutes prior to cocaine (90 mg/kg, ip). The animals were observed (30 minutes) to determine: latency to first seizure, number of seizures, and number of deaths after cocaine overdose. Fluoxetine, imipramine, buspirone, and pimozide had pro- or anticonvulsant effects depending on the dose. Smaller doses protected and higher doses increased cocaine-induced seizures and/or mortality. Naltrexone worsened and lithium protected against seizures. Thus, these results suggest that caution should be taken in the selection of pharmacotherapy and dosages for patients with cocaine addiction because of the possibility of potentiating cocaine toxicity.

Volatile Constituents of Psidium pohlianum Berg, and Psidium guyanensis Pers.

ABSTRACT The chemical composition of two wild Psidium species (Psidium pohlianum Berg, and P. guyanensis Pers.) collected in the National Park of Araripe, Crato-CE, Northeast of Brazil, are described and compared. Besides 1,8-cineole as the major constituent (40.5–60.3%), α-pinene, β-eudesmol and γ-eudesmol were found to be common compounds in both species. β-Pinene, elemol and spathulenol were found only in P. guyanensis, whereas p-cymene and α-terpinyl acetate were identified only in P. pohlianum.

Composição elementar e caracterização da fração lipídica de seis cultivares de caupi

The biochemical composition of the seeds of six bean - Vigna unguiculata (Walp) cultivars was determined and the lipid fraction of each of these cultivars was characterized. The results suggest that all analyzed seed flours share similar biochemical composition, although the cultivars Br-14 and CE-315 differ in relation to Br-9 and Br-17 in water content. The purified fatty acid fractions were characterized according to their lipid content. The cultivar Br-17 possesses high content of palmitic acid (58.2%) and low content of linoleic acid (6.4%) while Vita 7 possesses high contents of linoleic acid (21.8%) and relatively low content of palmitic acid (41%) on a comparative basis. Pentacosanoic and eicosanoic acids represent the minor fraction of lipids and the former does not occur in CE-315. The results suggest that different cultivars obtained by genetic combination may present relevant differences in their biochemical composition. Thus, differences in germination capacity, resistance to predators in the field or storage house may be related to over expression or inhibition of genes encoding synthesis of relevant molecules which refleet difference in composition as demonstrated in this study.

Volatile Constituents of Porophyllum ruderale Cass.

ABSTRACT The chemical composition of the unpleasantly odored steam distilled leaf oil of Porophyllum ruderale Cass. was determined as limonene (74.6%) and (E, E)-dodecadienal (21.8%). Adsorption chromatography over silica gel was used for the separation, whereas structure determination was accomplished mainly by GC/MS, 1H- and 13C-NMR, and comparison with literature data.

Volatile Constituents of Croton lundianus (F. Diedr.) Muell. and C. glandulosus (L.) Muell.

ABSTRACT The chemical composition of the essential oils of two Croton species (Croton lundianus and C. glandulosus) analyzed by GC/MS are described and compared. β-Caryophyllene and γ-elemene were identified as the major constituents in both oils along with α-humulene, δ-cadinene, allo-aromadendrene and torreyol, also found as common constituents. Certain components such as 1,8-cineole, linalool, α-ylangene, β-bourbonene and γ-cadinene were found only in C. lundianus, whereas germacrene B, (E)-nerolidol and α-cadinol were found only in C. glandulosus.

Volatile Constituents of Pilocarpus trachyllophus Holmes

ABSTRACT The chemical composition of the volatile oils from several plant parts of two Pilocarpus trachyllophus specimens from two different geographical regions of the Northeast of Brazil were compared by GC and GC/MS. 2-Tridecanone (67.75–84.38%) was the major component of the oils obtained from all plant parts, except for the leaf oil, followed by 2-pentadecanone (7.76–15.41%). In contrast, the leaf oil was rich in β-caryophyllene (20.04–21.09%), germacrene D (2.03–22.25%) and spathulenol (3.23–33.23%).

Caracterização química e bioquímica de sementes de Bauhinia variegata L.

Seeds of Bauhinia variegata were submitted to biochemical characterization through elementary analysis, protein fractioning and hemaglutinanting activity. The elementary analysis of seed showed high protein and lipid contents, with 29.41 and 14.89%, respectively. The linolenic acid was found in the lipidic constitution of the seeds and the mineral composition remained with in acceptable levels for the human consumption. The specific hemaglutinanting activity from different fractions of proteins (albumin, globulin, prolamin, glutelin acid and alkaline) demonstrated hemaglutinanting activity against native and enzyme treated rabbit erythrocytes. However, the fraction globulins showed the largest specific hemaglutinanting activity. Acid glutelin and albumin had a larger specific hemaglutinanting activity against tripisin-treated and papain-treated rabbit erythrocytes, respectively. Thus, for presenting high energy value, the seeds of Bauhinia variegata are an optional source for the feeding.