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Palavras-chave: Euphorbia tirucalli Linneau, avelós, atividade fotoprotetora A B S T R A C T: P h y t o c h e m i c a l a n a l y s i s a n d p h o t o p r o t e c t i v e a c t i v i t y o f theethanolic extract of Euphorbia tirucalli Linneau (Euphorbiaceae).Euphorbia tirucalli Linneau, popularly known as "avelos", "naked cock" or "naked dog", is used in popular medicinein order to treat cancer, antibiotic and antiviral diseases. Herbal medicines are often employed in order to assist or replace conventional therapies for the treatment of several diseases, including the prevention of the damage caused by ultraviolet radiation. Thus, the aim of this research was to evaluate the photoprotective potential and phytochemical screening of the ethanol extract of the aerial parts of avelos. The photoprotective activity was assessed by in vitrotrials according to the method adapted from Mansur, using the ethanol extract of the aerial parts. The results showed that the phytochemical study revealed the presence of reducing sugars, alkaloids, phenols, flavonoids, tannins, saponins, steroids and triterpenoids in ethanolic fraction. The extract showed antioxidant activity (EC 50 ) of 16,98 ± 0,35 μg.mL -1 , phenolic contents of 96,18 ± 1,33 mg EqAG/g and 63,57 ± 2,74 flavonoids from mg EqC/g that can advantage the photoprotective activity. Assessing the sun protection factor, it can be observed that all the tested concentrations (0,01 to 0,1 μg.mL -1 ) showed potential for photoprotection from ultraviolet radiation with a range of 6,05 to 19,84 FPS, respectively. These results suggest that the ethanol extract of Euphorbia tirucalli Linneau presents possible photoprotective effect.

Recebido em 13/2/02; aceito em 3/6/02 PROPOSITION OF A PHOTOCATALYTIC REACTOR TO INACTIVATE AIRBORNE MICROORGANISMS. The TiO 2 /UV photocatalytic reactor was investigated as an alternative system to inactivate airborne microorganisms. The experiments performed in the absence of the catalyst showed that direct photolysis was not efficient to destruct microorganisms, with only 30% of inactivation. Similar inactivation percentage was obtained using TiO 2 in absence of UV radiation. The destruction of microorganisms present in a contaminated indoor atmosphere, using the combination of TiO 2 /UV was very efficient, reaching more than 98% of destruction.Keywords: microorganism inactivation; photocatalytic reactor; TiO 2 /UV irradiation. INTRODUÇÃOAntes da década de 70, os problemas de saúde relacionados com a poluição do ar de ambientes interiores chamavam pouca atenção da comunidade científica. O interesse por este assunto tem crescido nos últimos anos, uma vez que as pessoas têm passado a maior parte do seu tempo em ambientes fechados 1 . As causas da poluição do ar de ambientes interiores podem ser decorrentes da má ventilação, da presença de material particulado, da contaminação química, especialmente por compostos orgânicos voláteis e, também, devido à contaminação microbiológica. A melhora na ventilação e o emprego de filtros apropriados podem amenizar tais problemas. No entanto, a presença de compostos orgânicos voláteis e microrganismos (bacté-rias, fungos e vírus), ainda que em pequenas concentrações, causa grande preocupação 2,3 . Um grande número de sintomas está relacionado com a má qualidade do ar. O conjunto destes sintomas foi definido como Síndrome do Edifício Doente 3,4 . Os principais incluem dor de cabeça, náusea, irritação nos olhos, problemas no sistema respiratório, sonolência e fadiga 5 . Inúmeros métodos têm sido propostos com o objetivo de mitigar o problema da contaminação biológica do ar interno, incluindo filtros para a remoção de materiais biológicos. Os filtros têm sido utilizados devido ao baixo custo e fácil manuseio, apresentando, entretanto, a desvantagem de não destruírem os microrganismos, e sim transferi-los para outro meio 4 . Um processo alternativo para inativar os microrganismos, proposto no presente trabalho, emprega o sistema TiO 2 /UV. No início da década de 70, Fujishima e Honda 6 descobriram que a água era decomposta a hidrogênio e oxigênio na presença de um eletrodo de dióxido de titânio e luz UV. Quando o TiO 2 é irradiado com luz UV com energia igual ou superior ao seu "bandgap" o par elétron/lacuna positiva é gerado na superfície da partícula deste semicondutor. Como conseqüência, a lacuna positiva pode oxidar água adsorvida na superfície do TiO 2 , formando radicais hidroxila (HO • ). Estes radicais são altamente reativos 7-9 , possuindo um elevado potencial de oxidação. Dentre as possibilidades de aplicação deste sistema, o emprego na área ambiental tem merecido maior destaque devido, principalmente, à possibilidade de alcançar a mineralização completa de vá-rios com...

Hepatic infection involving a parasite of the family Calyptosporidae was recorded in characiform fish from the Tocantins river in the Brazilian Amazon region. In the present study, an integrated comparative analysis of morphological characteristics, histological and structural traits, and the sequence of a partial fragment of the SSUrRNA gene provides support for the identification of a new calyptosporid species, found parasitising the hepatic tissue of the fish Triportheus angulatus, collected from the Tocantins River. This new species was named Calyptospora gonzaguensis n. sp. and had ovoid oocysts with a diameter of 19.6 AE 1.4 lm and four peripheral sporocysts, 9.2 AE 0.6 lm long and 3.9 AE 0.2 lm wide, enveloped individually in fine adhesive membrane, composed of an ellipsoid body and posterior extension, with a mean length of 2.2 AE 0.4 lm.

The objective of the present study was to evaluate the bioremediation of soils artificially contaminated with atrazine, glyphosate and pendimethalin by fungal consortia in biodegradation processes in microcosms. Biodegradation was evaluated from microbial respiration over a period of 15 days and genotoxicity analysis in Allium cepa roots exposed to elutriate samples at zero and 50 μg mL-1 concentrations of the herbicides after the biodegradation process. The results were submitted to analysis of variance, the Tukey test and the Fischer test (p<0.05%) for comparison of means. The Aspergillus fumigatus - Penicillium citrinum consortium had a larger capacity to degrade atrazine but metabolism was inhibited in the presence of glyphosate and pendimethalin. There was a delay in the mitotic index in the meristematic cells of the Allium cepa roots exposed to the elutriates in the 50 μg mL-1 atrazine and pendimethalin concentration. There was a cellular alteration in the metaphase phase of the cells exposed to the elutriates at the 50 μg mL-1 concentration of the three herbicides. The changes occurred were low, indicating that there was degradation of part of the herbicides.

Carbofuran (2.3-dihydro-2.2-dimethyl-benzofuranyl-N-methylcarbamate) is an insecticide belonging to the group of carbamates, widely used in pest control in crops with great commercial value, bioaccumulative and extremely toxic to the environment. An alternative to treat areas contaminated with pesticides is bioremediation, which consists of using microorganisms or their enzymes to remove persistent chemical compounds. Thus, the objective of this study was to determine the biodegradation of carbofuran, using the fungus Syncephalastrum racemosum, by evaluating fungal tolerance, enzymatic activity and quantifying residues by UV-Visible spectrophotometry. The results obtained showed that S. racemosum presented best biodegradation capacity at 15 µg mL-1carbofuran concentration (93.02%), with IVCM values of 21.95 cm day-1, laccase (0.712 U mL-1) and lignin peroxidase (0.005 U mL-1), after 168 h incubation. Thus, the degradation rate in the 25 to 100 µg mL-1 range showed values of 12.66 to 75.58%, respectively. Based on these results, the fungus has great potential for use in the bioremediation, minimizing the impacts of this pesticide on the environment.

Na busca pelo controle químico alternativo contra o Aedes aegypti, muitas pesquisas são desenvolvidas e incentivadas de modo a encontrar novas substâncias bioinseticidas de origem vegetal. Com isso, o objetivo deste trabalho foi avaliar o efeito larvicida do óleo essencial da arruda (Ruta graveolens Linneau) sobre as larvas do terceiro estádio do Aedes aegypti. A identificação dos componentes químicos presentes no óleo essencial de R. graveolens Linneau foi realizada por cromatografia gasosa-espectrometria de massa (CG/MS). A atividade larvicida foi determinada empregando os métodos de Reed-Muench e Pizzi em larvas do Aedes aegypti. Os resultados demonstraram que o óleo essencial de arruda apresentou a maior atividade larvicida, na concentração de 61,641 ± 1,72 μg mL-1. A eficiência da mortalidade do Aedes aegypti pode estar relacionada à presença de 2-nonanona e 2-undecanona (metilcetonas) no óleo essencial de arruda, componentes importantes de reconhecida eficácia como inseticida. Dessa forma pode-se verificar que o óleo essencial em estudo apresenta compostos químicos com efeito larvicida contra o A. aegypti.