Production of bacterial nanocellulose (BNC) is becoming increasingly popular owing to its environmentally friendly properties. Based on this benefit of BNC production, researchers have also begun to examine the capacity for cellulose production through microbial hosts. Indeed, several research groups have developed processes for BNC production, and many studies have been published to date, with the goal of developing methods for large-scale production. During BNC bioproduction, the culture medium represents approximately 30 % of the total cost. Therefore, one important and challenging aspect of the fermentation process is identification of a new cost-effective culture medium that can facilitate the production of high yields within short periods of time, thereby improving BNC production and permitting application of BNC in the biotechnological, medical, pharmaceutical, and food industries. In this review, we addressed different aspects of BNC production, including types of fermentation processes and culture media, with the aim of demonstrating the importance of these parameters.

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Bacterial nanocellulose (BNC) has desirable properties for wound healing such as high purity, good shape retention, and high water binding capacity. Bromelain is a protease found in pineapple tissues and has been applied in several fields, it has anti-inflammatory and anticancer properties, promotes cell apoptosis, amongst others. In this work, a BNC based device for the controlled release of bromelain was developed. BNC were submersed in sterilized bromelain solution and incubated at 25 °C under 100 rpm for 24 h. Physical-chemical properties, protein concentration, antioxidant and antimicrobial activities were measured. Results demonstrate that BNC could improve bromelain antimicrobial activity 9 times. Those findings allow concluding that bromelain is a promising molecule to be incorporated into BNC’s. The BNC’s characteristics seem to represent a new promising delivery system of the loaded biomolecule, and protected from external actions.

Recebido em 6/10/03; aceito em 2/3/04; publicado na web em 17/6/04 DETERMINATION OF ORGANOCHLORATED PESTICIDES IN THE WATER SUPPLY SYSTEM, DRINKING WATER AND SOIL OF THE REGION OF BAURU (SP). This paper evaluates the presence of organochlorinated pesticides in the water supply system of the city of Bauru, State of São Paulo, Brazil. Soil samples were collected in agricultural areas and water samples at several points of the water source (river) and the distribution net. The results of the analyses of the water from the source were compared with the Brazilian classification system for inland waters (CONAMA/86) and the results of analyses of treated water were compared with Brazilian standards for finished drinking water.Keywords: organochlorinated pesticides; water; soil; gas chromatograph. INTRODUÇÃOO grande emprego de pesticidas orgânicos na agricultura desde 1940 promoveu, além de colheitas com qualidade, um aumento na produtividade possibilitando o atendimento da demanda alimentícia na maioria dos países 1 . Apesar dos benefícios que trazem os pesticidas, o problema de intoxicações por defensivos agrícolas preocupa as autoridades, especialmente pelo fato de que essas intoxicações acontecem pela ingestão gradativa destes produtos que contaminam a água, o solo e uma variedade de alimentos 2 . O uso de muitos destes compostos foi proibido devido à constatação do efeito cumulativo e prejudicial, que ocorre pela transferência de pequenas quantidades ao longo das cadeias alimentares 3 . O emprego de pesticidas organoclorados, nas últimas décadas, tem produzido acumulação de resíduos tóxicos em vários ecossistemas em todo mundo. A concentração destes compostos tem alcançado níveis tóxicos em vários organismos terrestres, como pássaros e mamíferos, assim como em organismos aquáticos. Os resíduos de pesticidas organoclorados têm se tornado parte intrínseca dos ciclos biológicos, geológicos e químicos da Terra e têm sido detectados no ar, água, solo, plantas, invertebrados marinhos e mesmo, na neve e em pingüins da Antártica e do Ártico onde eles não são empregados 4,5 . Os pesticidas organoclorados são relativamente inertes e sua alta estabilidade está relacionada às ligações carbono-cloro. Estes compostos são muito estudados devido à alta toxicidade, baixa biodegradabilidade e biossolubilidade em tecido lipídico [6][7][8] . Alguns destes compostos podem persistir por 15 a 20 anos no solo e parte destes serem arrastados pelas chuvas (por lixiviação) para o interior dos cursos de água, que também recebem estes compostos através de efluentes industriais, de esgotos, de sedimentos, da atmosfera e por contaminação direta durante a aplicação. Assim, tanto as águas de mananciais de rios e represas que abastecem as populações, quanto os peixes que se alimentam de materiais retirados do fundo desses locais apresentam concentração de agrotóxicos, mesmo anos após a cessar a aplicação destes em regiões vizinhas 1 . A avaliação de efeitos cumulativos de pesticidas em ecossistemas aquáticos tem sido realizada através de testes de ...

Acne vulgaris treatments usually cause sensitivity, teratogenicity and bacterial resistance. Investigations of other therapeutic techniques, such as phototherapy, are highly relevant. Thus, we compared the effectiveness of two Acne vulgaris treatments in adolescents: peeling with salicylic acid (SA) and phototherapy. Teens were randomly divided into: group I, treatment with SA peels (10%) and group II, treatment with phototherapy (blue LED and red laser lights). Photographs were taken before and after ten sessions of each treatment, carried out weekly, and compared. To compare the differences between the treatments, the Student t-test was used. P values < 0.05 were considered significant. Both techniques are effective therapies for the treatment of acne in teenagers since the number of comedones, papules and pustules decreased significantly at the end of the session. However, when the two treatments were compared, phototherapy showed a significant difference in reducing the number of pustules. The combined use of red and blue lights due to their anti-inflammatory and wound-healing properties is a more efficient alternative for treating Acne vulgaris in relation to SA and proves more reliable and without side effects, improving the adolescents' skin health.