Current applications and different approaches for microbial L-asparaginase production

ABSTRACT L-asparaginase (EC 3.5.1.1) is an enzyme that catalysis mainly the asparagine hydrolysis in L-aspartic acid and ammonium. This enzyme is presented in different organisms, such as microorganisms, vegetal, and some animals, including certain rodent's serum, but not unveiled in humans. It can be used as important chemotherapeutic agent for the treatment of a variety of lymphoproliferative disorders and lymphomas (particularly acute lymphoblastic leukemia (ALL) and Hodgkin's lymphoma), and has been a pivotal agent in chemotherapy protocols from around 30 years. Also, other important application is in food industry, by using the properties of this enzyme to reduce acrylamide levels in commercial fried foods, maintaining their characteristics (color, flavor, texture, security, etc.) Actually, L-asparaginase catalyzes the hydrolysis of L-asparagine, not allowing the reaction of reducing sugars with this aminoacid for the generation of acrylamide. Currently, production of L-asparaginase is mainly based in biotechnological production by using some bacteria. However, industrial production also needs research work aiming to obtain better production yields, as well as novel process by applying different microorganisms to increase the range of applications of the produced enzyme. Within this context, this mini-review presents L-asparaginase applications, production by different microorganisms and some limitations, current investigations, as well as some challenges to be achieved for profitable industrial production.

Current applications and different approaches for microbial L-asparaginase production

ABSTRACT L-asparaginase (EC 3.5.1.1) is an enzyme that catalysis mainly the asparagine hydrolysis in L-aspartic acid and ammonium. This enzyme is presented in different organisms, such as microorganisms, vegetal, and some animals, including certain rodent's serum, but not unveiled in humans. It can be used as important chemotherapeutic agent for the treatment of a variety of lymphoproliferative disorders and lymphomas (particularly acute lymphoblastic leukemia (ALL) and Hodgkin's lymphoma), and has been a pivotal agent in chemotherapy protocols from around 30 years. Also, other important application is in food industry, by using the properties of this enzyme to reduce acrylamide levels in commercial fried foods, maintaining their characteristics (color, flavor, texture, security, etc.) Actually, L-asparaginase catalyzes the hydrolysis of L-asparagine, not allowing the reaction of reducing sugars with this aminoacid for the generation of acrylamide. Currently, production of L-asparaginase is mainly based in biotechnological production by using some bacteria. However, industrial production also needs research work aiming to obtain better production yields, as well as novel process by applying different microorganisms to increase the range of applications of the produced enzyme. Within this context, this mini-review presents L-asparaginase applications, production by different microorganisms and some limitations, current investigations, as well as some challenges to be achieved for profitable industrial production.

Dispensações de psicotrópicos anorexígenos no município de Juiz de Fora, Minas Gerais, Brasil / Prescriptions for anorectic psychotropic drugs in the municipality of Juiz de Fora, Minas Gerais, Brazil

A obesidade é um grave problema de saúde pública, com prevalência crescente em níveis epidêmicos. Tratamento farmacológico é uma das abordagens terapêuticas, mas deve ser precedido de mudança de hábitos alimentares e prática regular de atividades físicas. Há preocupação com o uso não racional de medicamentos anorexígenos, independente da condição de doença. O estudo avaliou as dispensações destes psicotrópicos realizadas em 2009, Juiz de Fora, MG. Realizou-se a pesquisa em boletins de consumo, enviados mensalmente à VISA municipal, e em registros obtidos no SNGPC. De 7.759 notificações pesquisadas, 93,3% foram dispensadas por farmácias magistrais e 6,7% por drogarias. Daquele total, 55,4% foram de anfepramona, 33,1% de femproporex e 11,5% de mazindol. Com base em relatório da Anvisa, as três substâncias apresentaram consumo maior no município (DDD/mil hab/ano) do que no país como um todo, para o mesmo período. O profissional com maior número de receitas aviadas teve 3.535 dispensações. Todas foram dispensadas em farmácias, sendo 99,5% em um único estabelecimento. O cenário mostra a dispensação de anorexígenos como problema relevante de saúde coletiva e indica a necessidade de reavaliação dos critérios de monitoramento de sua prescrição, dispensação e consumo.

Obesity is a serious public health issue of epidemic proportions. Although drug therapy is one of the therapeutic approaches, it should be preceded by a change in eating habits along with regular exercise. This study assessed prescription of such drugs in 2009, in Juiz de Fora, Minas Gerais, Brazil. Data were collected from consumption bulletins sent monthly to the municipal sanitary surveillance agency (VISA), and from the Brazilian National Management System of Controlled Products. Of the 7,759 notifications assessed, 93.3% were dispensed by prescription pharmacies and 6.7% by drugstores. Of that total, 55.4% were for amphepramone, 33.1% for femproporex, and 11.5% for mazindol. The three drugs had a larger consumption rate in the municipality (daily defined dose/1,000 inhabitants/day) than in the country as a whole, during the period under study. The professional with the highest prescription rate was responsible for 3,535 prescriptions. All of these were dispensed by prescription pharmacies, a single outlet being responsible for 99.5% of these prescriptions. This scenario shows that anorectic psychotropic drug prescription is a relevant public health issue and the criteria for monitoring the prescription and consumption of these drugs should be re-evaluated.

Estirpes bacterianas-padrão, formas de obtenção de doação e sua manutenção em laboratórios de ensino e pesquisa / Estirpes standard bacterial strains, ways of obtaining donation and maintenance in teaching and research

Boas Práticas de Laboratório (BPL) referem-se ao sistema da qualidade que contribui para a garantia da qualidade dos resultados. Essas práticas incluem o uso de estipes padrão para o controle do desempenho de meios de cultura, corantes e de reações. Estirpes padrão ou bactérias de referência são culturas provenientes de uma coleção de culturas reconhecida nacional e/ou internacionalmente, acompanhadas de um certificado com a descrição de suas características fenotípicas e genotípicas e outras informações relevantes. A conservação de suas características originais e viabilidade são requisitos essenciais para a sua reprodução em processos industriais e em experimentos de pesquisa. O objetivo deste trabalho foi reunir e disponibilizar informações sobre as formas de obtenção de doação de estipes-padrão para laboratórios de ensino e pesquisa e sobre a sua manutenção. Foram reunidas informações por meio de pesquisa bibliográfica sobre instituições doadoras de estirpes padrão, e formas de reativação e manutenção. A disponibilização deste material possibilita o cumprimento das BPL e a qualidade em trabalhos desenvolvidos.

Good Laboratory Practices (GLP) refer to the quality system that contributes to guarantee the quality of research results, including the use of standard strains to control the performance of culture media, dyes, and reactions. Standard strains or reference bacteria are cultures originated from a collection of cultures nationally and/or internationally recognized, followed by a certificate describing their phenotypic and genotypic characteristics and other relevant information. The preservation of their original characteristics is one of the essential requirements for their viability, important for their reproduction in industrial processes and in pure and applied research experiments. The objective of this work was to compile and disseminate information on the ways of obtaining donation of standard strains to teaching and research laboratories and their maintenance in microbiological analysis laboratories. Through a bibliographic survey, information was compiled on institutions that donate reference material and on methods of standard strain reactivation and adequate maintenance. The availability of this material through donations and adequate maintenance according to laboratory conditions allow fulfilling GLP requirements and the quality of the works developed.