To overcome the problem of enzyme extraction from cells due to the intracellular nature of beta-D-galactosidase and the poor permeability of the cell membrane to lactose, permeabilization of yeast cells was investigated. Permeabilized

whole cells have been claimed to have an advantage over more pure enzyme preparations. Wnt inhibitor In view of the advantages of immobilized cell systems over free cell systems, permeabilized cells were immobilized by an entrapment method in calcium alginate gel. A packed bed reactor together with this immobilized cell system has been used for hydrolysis of milk lactose in a continuous system.

RESULTS: Different process parameters (temperature, substrate feed rate, biomass load and time-course) were optimized to maximize lactose hydrolysis. The immobilized find more yeast cells (300 mg dry wt) resulted in 87.2% hydrolysis

of milk lactose at 30 degrees C and flow rate 7 mL h(-1) in a packed bed reactor system.

CONCLUSION: This convenient and relatively inexpensive method of immobilization, resulting in high hydrolysis potential in a continuous system, indicates that permeabilized yeast cells have the potential for the production of low lactose milk and milk products. (C) 2010 Society of Chemical Industry”
“Titanium dioxide (TiO2) nanoparticles, widely used for daily products, are believed to be biologically inert, but they may cause adverse effects on cells, presumably depending on the particle size and shape. One of the critical targets of TiO2 particles is epidermal keratinocytes, and their initial response to TiO2 may be production of pro-inflammatory cytokines. We therefore investigated the effects of four

types of TiO2 particles on cytokine expression/production by real-time reverse buy BVD-523 transcription polymerase chain reaction and enzyme-linked immunoassay. The TiO2 particles included three acicular types, FTL-100 (length, 1.68m; diameter, 130nm), FTL-200 (2.86, 210) and FTL-300 (5.15, 270), and one globular type, PT-301 (diameter, 270nm). Normal human epidermal keratinocytes (NHEK) were cultured with each of the TiO2 particles. During cultivation, the acicular forms of TiO2 were seen by scanning electron microscopy to be internalized by NHEK. The three acicular particles increased the mRNA expressions and supernatant productions of interleukin (IL)-1, IL-1, IL-6, tumor necrosis factor- and IL-8 in particle number-dependent manners, whereas globular PT-301 had very weak activity. Thus, TiO2 particles may induce skin inflammation depending on the size and shape, providing knowledge on their health usage.”
“BACKGROUND: Magnesium hydride is considered to be a promising hydrogen storage material because of its high gravimetric and volumetric storage capacities.