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Separation of surfactants from oil or water is essential for many research and industrial applications, such as in emulsions for biphasic catalysis and oil pipeline transportation. However, it is difficult to efficiently remove or recycle surfactants from the above systems due to their amphiphilic nature. Here, we report on redox-responsive Pickering emulsions stabilized by alumina nanoparticles and a selenium-containing surfactant at concentrations as low as 0.1 wt% and 1 × 10−6 M (≈0.001 cmc), respectively. Rapid demulsification can be achieved after the surfactant is converted from bola-type to trimeric form by a redox reaction, and the oil phase can be separated with minimal surfactant contamination (<0.005 ppb). In addition, the alumina nanoparticles together with the surfactant return to the aqueous phase after demulsification and are fully recoverable and re-usable. [ABSTRACT FROM AUTHOR]

Biphasic biocatalyses such as the hydrolysis of olive oil and the esterification of octanol with oleic acid were performed in a CO2/N2-switchable Pickering oil-in-water emulsion stabilized by silica nanoparticles hydrophobized in situ by a CO2/N2-switchable surfactant (N,N-dimethyldodecylamine). Compared with biphasic systems, the enzyme in the Pickering emulsions displays a higher reaction efficiency, and demulsification and recycling of the enzyme can be simply realized by bubbling with N2/CO2. Moreover, the recycled enzyme still possesses significant catalytic activity. [ABSTRACT FROM AUTHOR]

Previous research has revealed that n3 polyunsaturated fatty acids (PUFAs) exhibit anticancer activities. Lipids from a fish brain contain substantial n3 PUFAs. However, no research has been conducted on the action and mechanism of their potent anticancer activities. In this study, total lipids (TLs) from silver carp brain were isolated into polar lipids (PLs) and neutral lipids (NLs), and the anticancer potential of the lipid fractions (LFs) was investigated using the human cervical carcinoma HeLa cell line. LFs effectively inhibited the cell proliferation of HeLa cells in a time- and dose-dependent manner by cell cycle arrest at the S stage and by inducing apoptosis. Further analyses indicated that the loss of mitochondrial membrane potential could be one of mechanisms of apoptosis induced by LFs. Among the TLs, PLs have proven to be more effective in inducing cervical carcinoma cell death than NLs. This work will play a role in promoting lipids from silver carp brain as a potential preventive and therapeutic agent against human cervical carcinoma.