Model alginates

One of the philosophical bases of this work is the relative surface area benefit of microcapsules vs. hollow fibers. It is also felt that the alginate hydrogel would have a higher flux rate than the poly sulfone used in hollow fibers. The study of this technique, however, has only been advanced through a rat model. The survival rate for induced liver failure was 46.7% vs. 0% for untreated animals. 

The liposomes did not interfere with alginate capsule formation and were retained within the finished capsules. When myoglobin (used as a model protein) was not entrapped within liposomes but was simply enclosed as "free" protein within the coated alginate beads, 60% of it diffused out of the capsule over the first two days. In contrast, delayed release was achieved with microencapsulated liposomes containing myoglobin. Very little myoglobin appeared outside the capsules until 10 days after the start of the release experiment. It required a further 12 days to reach a level of 60% and not until 50 days after the start of the experiment was 100% release achieved. (Figure 5)... 

Non-linear parameter estimation methods can also be used to estimate ka and kt. Two methods are recommended. Both use an organism-water two-compartment model (i.e., Equation (29)). The first method is the BIOFAC method (Blau and Algin 1978). This method is based on the condition that the chemical concentration in the water is constant throughout the duration of the experiment, such that Equation 29 can be integrated to give... 

Fig. 7. Cofermentation of model solutions of glucose and xylose with P. st ip it is and S. cerevisiae separately immobilized (system G) and coimmobilized (system H) in Ca-alginate beads. The gel fraction in system G was made of 0.20 g/g of beads containing P. stipitis and 0.05 g/g of beads containing S. cerevisiae. The initial concentrations of P. stipitis and S. cerevisiae cells were 5.64 x 1012 and 1.89 x 10u cells/L, respectively. The gel fraction in system H was made of 0.25 g/g of beads containing P. stipitis and S. cerevisiae coimmobilized with a loading ratio of P. stipitis/S. cerevisiae of 4 g/g of dry cells. The total cells concentration was 6.01 x 1012 cells/L.

Whey proteins have been recently considered a potential alternative to the commonly used alginate [59, 61-63] for the production of gel beads. They have been used to entrap drugs such as retinol [64] and living microorganisms such as bifidobacteria [65], but until now not yeasts. A new immobilization system using whey proteins was then developed for entrapping the recombinant model yeasts WRP45073A1 in order to ensure their oral administration [66],... 

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