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This paper attempted to construct a high internal phase emulsion (HIPE) through altering interfacial behaviors using the electrostatic interaction between positive chitosan and negative octenyl succinic anhydride (OSA) starch. The partial polysaccharide complex of OSA starch/chitosan was used to stabilize HIPE, which was able to adsorb at the oil droplet interface and prevent the coalescence of oil droplets. The wettability of OSA starch was enhanced with the addition of positively charged chitosan, leading to the formation of partial complexes. The impact of pH and concentration of chitosan on the droplet size, surface charge, and interface behavior were investigated, and the formation of the polysaccharide complex was further confirmed by atomic force microscopy. The presence of the OSA starch/chitosan complex facilitated the formation of stable HIPE with a gel-like structure and satisfactory centrifugal and oxidative stability. These results are useful to provide information for fabricating polysaccharide-based HIPE delivery systems, which may help expand their application in the food industry.

A bacterial strain EMS with the capability of degrading microcystins (MCs) was isolated from Lake Taihu, China. The bacterium was tentatively identified as a Stenotrophomonas sp. The bacterium could completely consume MC-LR and MC-RR within 24 hours at a concentration of 0.7 μg/mL and 1.7 μg/mL, respectively. The degradation of MC-LR and MC-RR by EMS occurred preferentially in an alkaline environment. In addition, mlrA gene involved in the degradation of MC-LR and MC-RR was detected in EMS. Due to the limited literature this gene has rare homologues. Sequencing analysis of the translated protein from mlrA suggested that MlrA might be a transmembrane protein, which suggests a possible new protease family having unique function.

The poor water solubility and oral bioavailability of many lipophilic polyphenols can be improved through the use of colloidal delivery systems. In this study, a pH-driven method was used to encapsulate curcumin, quercetin, and resveratrol within nanoliposomes. This method is based on the decrease in water-solubility of certain polyphenols when they move from alkaline to acid conditions. However, the chemical stability of some polyphenols is relatively poor under alkaline conditions. For this reason, the impact of pH on the chemical degradation of the three polyphenols was studied. The polyphenols were then encapsulated within nanoliposomes using the pH-driven method and the encapsulation efficiency (EE) and chemical stability were determined. The EE of curcumin, quercetin, and resveratrol in the nanoliposomes was 100, 54, and 93%, respectively. Differences in the EE were mainly attributed to differences in their stability under alkaline conditions. Our results show that the application of this method to other lipophilic polyphenols depends on the impact of pH on their solubility and chemical stability, which needs to be established on a case-by-case basis.

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The complex nanoliposomes encapsulating both a hydrophilic drug vitamin C (vit C) and hydrophobic drug medium-chain fatty acids (MCFAs) was prepared by combining double emulsion method with dynamic high pressure microfluidization. The complex nanoliposomes was further freeze-dried under −86 °C for 48 h with sucrose at the sucrose/lipids ratio of 2:1(w/w) in order to enhance its stability. The freeze-dried complex nanoliposomes under the suitable conditions exhibited high entrapment efficiency of MCFAs (44.26 ± 3.34)%, relatively high entrapment efficiency of vit C (62.25 ± 3.43)%, low average size diameter (110.4 ± 7.28) nm and good storage stability at 4 °C for 60 days with slight changes in mean particle diameter and drug entrapment efficiencies. The results of transmission electron microscopy of freeze-dried complex nanoliposomes also showed that the freeze-dried samples with sucrose were stable without great increase in their particle sizes and without destroying their spherical shape. The results indicated that sucrose presented well protection effects in MCFAs-vit C complex nanoliposomes, suggesting the possibility of further usage in commercial liposomes.