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This work aims to advance the understanding of the synergistic mechanism of lecithin and polymers (alginate, CMC, and PVP) in stabilizing curcumin, with a major focus on understanding the nanocomplex formation process and the main binding energy between molecules. It is demonstrated that lecithin and polymers have a synergistic effect in increasing the thermal acid, light, and digestion stability of curcumin. The potential mechanism is that the hydrophobic parts of curcumin molecules are first anchored at the region of the hydrophobic cavity of lecithin by van der Waals, while the hydrophilic parts are outward and are further encapsulated by hydrophilic polymers by van der Waals and electrostatic interaction to form a protective shell. This study contributes to our understanding of the synergistic mechanism of lecithin, polymers, and hydrophobic compounds, which can promote the synergistic use of lecithin and polymers to prepare nanocomplexes as an important tool for delivering bioactive compounds.

Low stability and bioaccessibility are two unfavourable features that limit the application of many hydrophobic compounds. In this study, lecithin was complexed with polyvinylpyrrolidone K30 (PVPK30) to enhance the stability and bioaccessibility of curcumin via a precipitation-ultrasonication method. The curcumin-loaded nanocomplexes exhibited uniform sizes (∼120 nm), low polydispersity (∼0.22), and negative zeta potential (∼−45 mV). Curcumin was molecularly dispersed in lecithin-PVP complexes and exhibited an amorphous state. The curcumin-loaded nanocomplexes possess excellent dilution, thermal, and storage stability. More importantly, in vitro simulated gastrointestinal digestion experiment showed that the nanocomplexes could significantly improve the bioaccessibility of curcumin, reaching 105 times. Molecular dynamics simulation study revealed that lecithin and PVPK30 stabilized curcumin through hydrogen bonds, π-π interactions, and hydrophobic interactions. Our study provides a new way for curcumin and other hydrophobic compounds with excellent stability and bioaccessibility.

Objective To establish a rat liver transplantation model under direct vision of single operator and to explore the effect of different perfusion methods on the quality of the donor liver. Methods On the basis of the "two-cuff method" established by Kamada, the operation details were improved to established the rat liver transplantation model. The recipient rats were divided into two groups according to different perfusion methods, group A (perfusion via abdominal aorta) and group B (perfusion via portal vein). The perfusion effect, operation time, operation success rate, postoperative liver function, liver graft pathological manifestations and survival were compared between the two groups. Results There were more residual red blood cells in sinus hepaticus in group B than in group A after perfusion. Both the donor liver perfusion time and donor operation time were longer in group A than those in group B, and the differences were statistically significant (both P < 0.01). The success rate of operation in group A and group B was 77% and 71%, respectively. At 3 d after liver transplantation in rats, the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total bilirubin (TB) of the rats in the two groups were significantly higher than normal. At 7, 30 d after operation, compared with group A, the levels of ALT, AST and TB in group B were significantly increased, and the differences were statistically significant (all P < 0.01-0.05). The liver pathological examination showed that the degree of inflammatory reaction in the liver and degree of destruction of liver tissue in group B were more severe than those in group A, but there was no significant difference in long-term survival rate between the two groups. Conclusions Although the perfusion time and donor operation time of rat liver transplantation model were slightly prolonged by means of abdominal aorta perfusion, the perfusion effect was better, which can reduce liver tissue damage after operation and restore liver function to normal levels more quickly.

Based on social capital theory, related factors of three dimensions（structure dimension, cognition dimension and relation dimension）of farmer social capital are taken as independent variables, and famer’s willingness to cooperatively supply agricultural disaster reduction public goods is taken as dependent variable. Taking 515 farmers in 27 villages of Hubei Province as investigation objects, the influence of farmer social capital on cooperative supply willingness of agricultural disaster reduction public goods is explored by Logistic regression model. Research results show that social solidarity, common value concept, social trust and reciprocal content have positive impact on farmer’s willingness of cooperative supply, while annual household income, number of agricultural disaster reduction public goods and social network have negative impact on farmer’s willingness of cooperative supply.