Generation of α-Linolenic Acid Ethyl Ester Microparticles from Silkworm Pupae Oil by Microfluidic Droplet


The instability of polyunsaturated fatty acids to peroxidation often hinders the practical application of oil-based products, and oil-in-water (o/w) emulsions are important components of a wide range of drugs, functional foods and consumer care products. Caffeic acid (CA)-grafted chitosan (CA-g-Ch) was successfully synthesized as a novel wall material and used to embed α-linolenic acid ethyl ester (ALAEE) using microfluidic droplet technology. The results indicated that CA-g-Ch has lower viscosity and stronger emulsification properties than chitosan, and its solution is a Newtonian fluid with good fluidity. When the flow rates of the disperse phase and continuous phase were 0.45 µL/min and 0.75 µL/min, the diameter of the droplets prepared with a 0.25% concentration of Tween 20 was 29 µm, and the droplets had obvious monodispersity. In addition, the droplets were difficult to form normally when the concentration was higher than 1%. The ALAEE microcapsules were easily prepared using freeze-dried droplets. The antioxidant activity of ALAEE microcapsules measured by the DPPH method was 84.96%, which was 7.06 times higher than that observed for untreated ALAEE. Therefore, the monodisperse ALAEE-M prepared by microfluidic microdroplet technology combined with antioxidant wall materials has successfully improved the antioxidant properties of core materials, showing promise for food or drug applications.

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This study was financially supported by the Key Research and Development Program (Modern Agriculture) of Jiangsu Province (BE2017322), the Key Research and Development Program (Modern Agriculture) of Zhenjiang City (NY2017010), the Six Talent Peaks Project of Jiangsu Province (2015-NY-018), the 333 High-level Talent Training Project of Jiangsu Province (Year 2018), and the Shen Lan Young scholars program of Jiangsu University of Science and Technology (Year 2015).

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Bai, Z., Zhang, S., Liu, X. et al. Generation of α-Linolenic Acid Ethyl Ester Microparticles from Silkworm Pupae Oil by Microfluidic Droplet. Waste Biomass Valor 10, 3781–3791 (2019).

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  • α-Linolenic acid ethyl ester
  • Covalent grafting
  • Oxidative stability
  • Antioxidant
  • Microfluidic
  • Microparticle