Production, purification and characterization of a milk clotting enzyme from Bacillus methanolicus LB-1.

Bacillus methanolicus LB-1 isolated from traditional rice wine was found to produce a milk clotting enzyme (MCE), and its fermentation conditions were optimized using response surface methodology. Then the MCE was produced by ethanol precipitation, and further chromatography separation resulted in a 10.46-fold purification with a 59.28% recovery. The MCA (milk clotting activity) of the purified MCE reached 597,310 ± 0.13 SU/g. The optimal temperature of the MCE was determined to be 50 °C and it was stable in the low temperature range of 40-45 °C. The MCE had an optimum pH of 6.5, and it was stable under neutral conditions. Calcium chloride at the concentration of 25 mM was found to be the most effective stimulus. The MCE was identified by LC-MS to be a putative protein (ID I3EB99) containing 759 amino acids with a molecular weight of 80.37 kDa and a pI of 9.23.

Productive profile of cattle-rearing farms in the state of Minas Gerais, Brazil, 2002 / Perfil produtivo de propriedades produtoras de bovinos do Estado de Minas Gerais, Brasil, 2002

A descriptive cross-sectional study was conducted in the state of Minas Gerais, Brazil, with the aim to assess aspects of cattle production. A multistage clustering model was used to select 2,202 farms in seven cattle production strata in the state, and a questionnaire was applied to obtain information related to the characterization of the farms and their management of animal reproduction and production. The study showed that livestock-rearing in Minas Gerais continues to be unspecialized. Triângulo Mineiro and North were the regions that used most technology and had highest beef cattle activity. The Zona da Mata region showed the least use of technology and had the smallest farms. Milk production in this state was distributed among all strata, but was concentrated among a few producers in the stratum of highest production, especially in the region of Alto Paranaíba. This study showed a great heterogeneity among the strata regarding the characteristics of type of exploitation, type of rearing, herd size, specialization and milk production. Thus, it validated the stratification established by the Ministério da Agricultura Pecuária e Abastecimento ­ MAPA (Brazilian Ministry of Agriculture, Livestock and Food Supply), thereby suggesting that these strata should be maintained for further epidemiological studies.(AU)

Com o objetivo de avaliar os aspectos da produção de bovinos no Estado de Minas Gerais, realizou-se um estudo transversal descritivo. Foram selecionadas, pelo método de conglomerados multiestágios, 2.202 propriedades distribuídas em sete estratos produtores de bovinos do estado, nas quais foram aplicados questionários visando obter informações relacionadas à caracterização da propriedade e do manejo produtivo e reprodutivo dos animais. A pecuária bovina em Minas Gerais ainda é pouco especializada, sendo a Região do Triângulo Mineiro considerada a mais tecnificada e com maior expressão na exploração de animais de corte, juntamente com a Região Norte de Minas. A Zona da Mata foi considerada a menos tecnificada e constituída pelas menores propriedades. A produção de leite no estado está distribuída por todos os estratos, no entanto é concentrada em poucos produtores das faixas de maior produção, com destaque para a Região do Alto Paranaíba. O estudo mostrou que há grande heterogeneidade entre os estratos no que se refere às características tipo de exploração, tipo de criação, tamanho de rebanho, especialização e produção de leite, validando a estratificação estabelecida pelo Ministério da Agricultura, Pecuária e Abastecimento (MAPA) e sugerindo sua manutenção em futuros estudos epidemiológicos.(AU)