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A mathematical modeling, based on the two-phase theory of batch fluidized bed drying of type A particles and type B particles pharmaceutical powders, was performed. A perfectly mixed flow bubbling regime and an axially dispersed plug flow turbulent regime with a freeboard section were assumed. The experiments were carried out in a pilot-scale bed and in an industrial scale bed. The experimental sorption isotherms were used to model the falling rate drying period. The influence of the particles hygroscopic properties on the drying rate and on the temperature profile was discussed. The simulated solid moisture content and temperature profiles are in good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

Astaxanthin (ATX) is a marine carotenoid known for its powerful antioxidant and neuroprotective properties. In this study, we investigated the in vitro and in vivo potential inhibitory effect of ATX on the aldose reductase (AR) activity, a key enzyme in the polyol pathway responsible for the pathogenesis of diabetic complications including diabetic retinopathy (DR). The gerbil Psammomys obesus (P. ob.), an animal model for type 2 diabetes and DR has been used. The erythrocyte and retinal AR activity of P. ob. individuals were, respectively, assessed monthly and at the 7th month during a 7‐month hypercaloric diet (HD) using a NADPH oxidation method. Meanwhile, the body weight and blood glucose of the gerbils were monitored. After 7 months, P. ob. individuals were fed with ATX (4.8 mg/kg of body weight) once a day for 1 week. The results showed that the HD‐fed animals developed significant obesity and hyperglycemia in comparison with controls. Erythrocyte AR activity showed a progressive and significant increase in the HD‐fed group compared with controls. Retinal AR activity was higher in the 7‐month HD‐fed group compared with controls. Erythrocyte AR activity was markedly decreased after ATX‐treatment in vitro and in vivo. These findings suggested that ATX inhibited the erythrocyte AR activity and could be used for DR prevention and/or early treatment. [ABSTRACT FROM AUTHOR]