Herein, a pH-switchable Pickering interfacial biocatalysis (PIB) system is proposed and applied to a solvent-free biphasic biocatalysis. The oil-inwater emulsion was stabilized by amine-functionalized hollow mesoporous silica nanospheres (HMSS-N), which is functioned as emulsifiers of PIB and carriers of lipase AYS. The smart emulsifiers exhibited switch of the surface wettability behaviors in response to abrupt changes of pH. Under the optimality conditions, the immobilized lipase loading amount, activity, and expressed activity were 174.1 mg g −1 , 9073 U g −1 , and 52.1 U g −1 protein, respectively, at pH 6. Based on it, the hydrolysis of rice bran oil and esterification with phytosterols to produce phytosterol esters (PEs) were successfully performed. Compared with the conventional free enzyme one-phase system, the PIB system displays a higher reaction efficiency (catalytic efficiency value 6.88 mmol g −1 h −1 , 20-fold enhancement). In addition, the system maintains 95% residual activity after 10 reaction cycles with 38.3 g products/g biocatalyst average productivity, complying with the requirements of industry-accepted standards. In each cycle, the demulsification is realized simply by in situ pH regulation. Therefore, this paper provides a powerful and green platform for oil−fat modification and stimuli-responsive interfacial biocatalysis with the advantages of a high efficiency, sustainability, a solvent-free process, and multirecyclability.

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Enzymatic esterification of resveratrol is crucial for its potential application in lipophilic foods and drugs. However, the poor activity of the free enzyme hinders the reaction. In this work, the highly efficient enzymatic synthesis of resveratrol ester derivatives was achieved by immobilized lipase on hydrophobic modified hollow mesoporous silicon spheres (HMSS-C 8 ). We preliminarily explored the use of Candida sp. 99-125 lipase (CSL) for the acylation of resveratrol, with a regioselectivity toward 3-OH-over 4'-OH-acylation. HMSS-C 8 provided ideal accommodation for CSL with a loading capacity of up to 652 mg/g. The catalytic efficiency of CSL@HMSS-C 8 was 15 times higher than that of free CSL, and the conversion of resveratrol reached 98.7% within only 2 h, which is the fastest value recorded in the current literature. After 10 cycles, the conversion remained up to 86.3%. Benefiting from better lipid solubility, the relative oxidation stability index values of oil containing monoester derivatives were 43.1%−68.8% and 23.9%−33.2% higher than that of refined oil and oil containing resveratrol, respectively. This research provides a new pathway for efficient enzymatic synthesis of resveratrol ester derivatives and demonstrates the potential application of resveratrol monoester derivatives as a group of excellent lipid-soluble antioxidants.