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1.
Pharmaceutics ; 13(1)2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33374100

RESUMO

Since 1961, L-asparaginase has been used to treat patients with acute lymphocytic leukemia. It rapidly depletes the plasma asparagine and deprives the blood cells of this circulating amino acid, essential for the metabolic cycles of cells. In the search for viable alternatives to produce L-asparaginase, this work aimed to produce this enzyme from Escherichia coli in a shaker and in a 3 L bioreactor. Three culture media were tested: defined, semi-defined and complex medium. L-asparaginase activity was quantified using the ß-hydroxamate aspartic acid method. The defined medium provided the highest L-asparaginase activity. In induction studies, two inducers, lactose and its analog IPTG, were compared. Lactose was chosen as an inducer for the experiments conducted in the bioreactor due to its natural source, lower cost and lower toxicity. Batch and fed-batch cultures were carried out to reach high cell density and then start the induction. Batch cultivation provided a final cell concentration of 11 g L-1 and fed-batch cultivation produced 69.90 g L-1 of cells, which produced a volumetric activity of 43,954.79 U L-1 after lactose induction. L-asparaginase was produced in a shaker and scaled up to a bioreactor, increasing 23-fold the cell concentration and thus, the enzyme productivity.

2.
Bioresour Technol ; 302: 122847, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32008863

RESUMO

Advanced biorefineries, which aim at valorizing biomass (from agriculture, forestry, aquaculture, among others) into a wide spectrum of products and bioenergy, are seen today as key to implement a sustainable biobased economy. Although different concepts of biorefinery are currently under development, further research and improvement are still required to obtain environmentally friendly and economically feasible commercial scale biorefineries. Valorization of all biomass components and integration of different disciplines are some of the strategies that have been considered to improve the economic and environmental performance. This paper summarizes and discusses the most recent innovations and strategic orientations for the development of advanced biorefineries. Focus is given on the valorization of non-carbohydrate components of biomass (protein, acetic acid and lignin), on-site and tailor-made production of enzymes, big data analytics, and interdisciplinary efforts. The idea is to provide new insights and directions to support the development and large-scale implementation of biorefineries.


Assuntos
Agricultura , Lignina , Biomassa , Agricultura Florestal
3.
Artigo em Inglês | MEDLINE | ID: mdl-30687702

RESUMO

L-Asparaginase (ASNase) is a vital component of the first line treatment of acute lymphoblastic leukemia (ALL), an aggressive type of blood cancer expected to afflict over 53,000 people worldwide by 2020. More recently, ASNase has also been shown to have potential for preventing metastasis from solid tumors. The ASNase treatment is, however, characterized by a plethora of potential side effects, ranging from immune reactions to severe toxicity. Consequently, in accordance with Quality-by-Design (QbD) principles, ingenious new products tailored to minimize adverse reactions while increasing patient survival have been devised. In the following pages, the reader is invited for a brief discussion on the most recent developments in this field. Firstly, the review presents an outline of the recent improvements on the manufacturing and formulation processes, which can severely influence important aspects of the product quality profile, such as contamination, aggregation and enzymatic activity. Following, the most recent advances in protein engineering applied to the development of biobetter ASNases (i.e., with reduced glutaminase activity, proteolysis resistant and less immunogenic) using techniques such as site-directed mutagenesis, molecular dynamics, PEGylation, PASylation and bioconjugation are discussed. Afterwards, the attention is shifted toward nanomedicine including technologies such as encapsulation and immobilization, which aim at improving ASNase pharmacokinetics. Besides discussing the results of the most innovative and representative academic research, the review provides an overview of the products already available on the market or in the latest stages of development. With this, the review is intended to provide a solid background for the current product development and underpin the discussions on the target quality profile of future ASNase-based pharmaceuticals.

4.
Bioresour Technol ; 243: 264-272, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28675840

RESUMO

Surfactants are amphiphilic molecules with large industrial applications produced currently by chemical routes mainly derived from oil industry. However, biotechnological process, aimed to develop new sustainable process configurations by using favorable microorganisms, already requires investigations in more details. Thus, we present a novel approach for biosurfactant production using the promising yeast Aureobasidium pullulans LB 83, in stirred tank reactor. A central composite face-centered design was carried out to evaluate the effect of the aeration rate (0.1-1.1min-1) and sucrose concentration (20-80g.L-1) in the biosurfactant maximum tensoactivity and productivity. Statistical analysis showed that the use of variables at high levels enhanced tensoactivity, showing 8.05cm in the oil spread test and productivity of 0.0838cm.h-1. Also, unprecedented investigation of aeration rate and sucrose concentration relevance in biosurfactant production by A. pullulans in stirred tank reactor was detailed, demonstrating the importance to establish adequate conditions in bioreactors, aimed to scale-up process.


Assuntos
Reatores Biológicos , Glucanos , Biotecnologia , Fermentação
5.
Braz. j. microbiol ; 47(supl.1): 77-85, Oct.-Dec. 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-839324

RESUMO

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.


Assuntos
Humanos , Animais , Asparaginase/biossíntese , Microbiologia Industrial , Indústria Farmacêutica , Fermentação , Antineoplásicos , Asparaginase , Indústria Alimentícia
6.
Braz J Microbiol ; 47 Suppl 1: 77-85, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27866936

RESUMO

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.


Assuntos
Antineoplásicos , Asparaginase/biossíntese , Indústria Farmacêutica , Fermentação , Microbiologia Industrial , Animais , Asparaginase/metabolismo , Indústria Alimentícia , Humanos
7.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469625

RESUMO

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.

8.
Ciênc. Saúde Colet. (Impr.) ; 17(12): 3331-3342, dez. 2012. graf, tab
Artigo em Português | LILACS | ID: lil-656475

RESUMO

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.


Assuntos
Humanos , Depressores do Apetite/uso terapêutico , Obesidade/tratamento farmacológico , Psicotrópicos/uso terapêutico , Brasil , Cidades , Estudos Transversais , Prescrições de Medicamentos/estatística & dados numéricos , Estudos Retrospectivos
9.
Cien Saude Colet ; 17(12): 3331-42, 2012 Dec.
Artigo em Português | MEDLINE | ID: mdl-23175409

RESUMO

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.


Assuntos
Depressores do Apetite/uso terapêutico , Obesidade/tratamento farmacológico , Psicotrópicos/uso terapêutico , Brasil , Cidades , Estudos Transversais , Prescrições de Medicamentos/estatística & dados numéricos , Humanos , Estudos Retrospectivos
10.
Molecules ; 17(9): 10344-54, 2012 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-22932215

RESUMO

Guaco (Mikania glomerata Sprengel) syrup is one of the most popular herbal medicines used to treat the symptoms of asthmatic bronchitis, cough and hoarseness. The coumarin 2H-1-benzopyran-2-one, is one of the major constituents of Guaco and contributes to its pharmacological effects. The pharmaceutical capsule form of dry extract of Guaco is recommended by the Brazilian Program of Medicinal Plants and Herbal Medicines and used in primary health care. In order to identify a new protocol to obtain the raw material for Guaco capsule production we evaluated two methods, including a freezedrying process (lyophilization) and the spray-dryer technique, as well as the use of two adjuvants, Maltodextrins and Aerosil®, in different concentrations. The coumarin levels of the dried extracts were analyzed by UV-spectrophotometry and HPLC-UV/DAD. The adjuvant Aerosil® 8% showed better dry powder physical appearance. Lyophilization was observed to be the best process to obtain the dry extract of Guaco based on the measured coumarin levels.


Assuntos
Cumarínicos/análise , Mikania/química , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão , Liofilização , Folhas de Planta/química , Espectrofotometria
11.
Rev. interdisciplin. estud. exp. anim. hum. (impr.) ; 3(único): 21-26, janeiro 2011. ilus, tab
Artigo em Português | LILACS | ID: biblio-964462

RESUMO

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.


Assuntos
Viabilidade Microbiana , Laboratórios/normas , Microbiologia , Manutenção
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