Green synthesis of isomaltulose from cane molasses by Bacillus subtilis WB800-pHA01-palI in a biologic membrane reactor.

A green process and environmentally benign process is highly desirable in the development of enzymatic catalysis. In this work, the shuttle plasmid pHA01 was constructed and the sucrose isomerase (SIase) was expressed in Bacillus subtilis WB800. The optimal nitrogen and carbon sources for SIase expression were yeast extract (15g/L) and un-pretreated cane molasses (UCM, 20g/L), respectively. After the UCM fed, the whole cell activity reached 5.2U/mL in a 7.5L fermentor. Optimum catalytic temperature and pH of whole cell were 35°C and 5.5, respectively. Although the biologic membrane reactor (BMR) system consecutively worked for 12 batches, the sucrose conversion remained higher than 90%, indicating the BMR system had a greater operational stability. Furthermore, isomaltulose production using the BMR system with low-cost cane molasses as its substrate not only reduces the production cost and mediates environmental pollution, but also solves the genetic background problem of the non-food-grade strains.

Efficient production of lactulose from whey powder by cellobiose 2-epimerase in an enzymatic membrane reactor.

In this study, the gene encoding cellobiose 2-epimerase from Caldicellulosiruptor saccharolyticus (CsCE) was successfully expressed in Bacillus subtilis WB800. After the fermentation medium optimization, the activity of recombinant strain was 4.5-fold higher than the original medium in a 7.5L fermentor. The optimal catalytic pH and temperature of crude CsCE were 7.0 and 80°C, respectively. An enzymatic synthesis of lactulose was developed using cheese-whey lactose as its substrate. The maximum conversion rate of whey powder obtained was 58.5% using 7.5 U/mL CsCE. The enzymatic membrane reactor system exhibited a great operational stability, confirmed with the higher lactose conversion (42.4%) after 10 batches. To our best knowledge, this is the first report of lactulose synthesis in food grade strain, which improve the food safety, and we not only realize the biological production of lactulose, but also make good use of industrial waste, which have positive impact on environment.

Hernioplastia abdominal com implante de centro frênico heterólogo em felino - Relato de Caso / Abdominal hernioplasty with phrenic center heterologous graft in feline - Case report

Emprego de membranas biológicas na reconstituição tecidual tem se destacado na Medicina Veterinária. O uso de enxertos autólogos ou implantes homólogos e heterólogos conservados tem sido cada vez mais freqüente. Uma gata, adulta foi atendida no Serviço Clínico-cirúrgico Veterinário da Universidade Federal de Mato Grosso, com histórico de aumento súbito e progressivo do volume abdominal. No exame físico detectou-se hérnia abdominal ventral traumática. Observou-se retração dos músculos abdominais, com aproximadamente dois terços do perímetro abdominal ausente de musculatura. Optou-se pelo emprego de implante de centro frênico eqüino conservado em glicerina a 98 por cento para hernioplastia, o qual foi fixado à musculatura remanescente. A paciente foi acompanhada por um período de um ano, sem qualquer complicação ou sinal de rejeição, o que permite sugerir como alternativa viável no reparo de herniorrafia abdominal em felinos.