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In this research, carboxymethylchitosan (CMCS)-coated proliposomes (CM-PL) were prepared in an attempt to deliver coix seed oil (CSO) using conventional ethanol injection followed by surface modification and spray drying. Conventional uncoated liposomes (un-L), CMCS-coated liposomes (CM-L) and uncoated proliposomes (un-PL) were also prepared for comparison. The morphology, encapsulation efficiency (EE), particle size, zeta potential, stability, and CSO release performance were investigated for all samples. The results indicated that CM-PL possessed smoother surface, better heterogeneous size distribution, higher EE and improved stability compared with other samples. Transmission electron microscopy (TEM) showed that rehydrated CM-PL were spherical particles with CMCS layers surrounding the surface of conventional liposomes. The coating mechanism was probably due to H-bonding interactions between CMCS and the interfacial regions of the phosphatidylcholine bilayer. In addition, controlled release of CSO from coated proliposomes was obtained with more sustained release in simulated intestinal fluid (SIF) than in simulated gastric fluid (SGF).

In this work, resveratrol (Res) was incorporated into chitosan microspheres for controlled release and stabilisation. The microspheres were prepared by emulsion chemical cross-linking method, and vanillin was used as the novel cross-linker. The microspheres showed a smooth surface with irregular small particles and internal voids with a size distribution between 53 and 311 mu m. Interpenetrating network cross-linking mechanisms might account for the Schiff base reaction between chitosan and vanillin. The encapsulation efficiency of Res within microspheres was up to 93.68%. Res contained within microspheres was protected from light and heat compared with the free Res. In addition, release behaviours were governed by two distinct stages and dependent on pH of release media. Diffusion, swelling and erosion mechanisms might coexist for the full controlled release and Higuchi was the Most Suitable model for the whole release procedure, Thus, controlled release and stabilization of Res were achieved through incorporation of Res into cross-linked chitosan microspheres by vanillin. (C) 2009 Elsevier Ltd. All rights reserved.

A study to compare the uptake, translocation, and distribution of selenium (Se) in soybean planted in natural seleniferous soil in Fengcheng city of China was conducted to clarify the relationship between the Se content levels of soybean proteins and their radical scavenging activity. The data showed that the total Se content in different parts of soybean plants varied with the growth periods. The selenoprotein (Se-SPI) content increased remarkably with the increase of Se content in seleniferous soils. The Se-SPI content obtained from the region with the highest Se level was almost 18 times higher than that of the control group, while antioxidant activities were about 4-fold compared to the control, suggesting that Se played a positive role in enhancing the antioxidant activity of Se-SPI. The increase in the Se level also led to changes in amino acids composition, but with nearly no effects on the subunit composition of soybean Se-SPI.