Formulation and characterization of astaxanthin-enriched nanoemulsions stabilized using ginseng saponins as natural emulsifiers
Version 2 2024-06-06, 03:17Version 2 2024-06-06, 03:17
Version 1 2018-04-27, 13:43Version 1 2018-04-27, 13:43
journal contribution
posted on 2024-06-06, 03:17authored byG Shu, N Khalid, Z Chen, MA Neves, Colin BarrowColin Barrow, M Nakajima
In this study ginseng saponins (GS) were used as natural emulsifiers to formulate and stabilize O/W nanoemulsions loaded with astaxanthin (AST). GS were found to be highly effective at reducing the interfacial tension at the soybean oil-water interfaces, and were capable of producing nano-scaled droplets (d4,3 ≈ 125 nm) using a high-pressure homogenizer. The droplet size of the nanoemulsions decreased with increasing emulsifier concentration and homogenization pressure. The nanoemulsions were stable without droplet coalescence against thermal treatment (30-90 °C, 30 min), and over a narrow range of pH values (7-9). GS-coated droplets were unstable in acidic conditions (pH 3-6) and in the presence of salt (>25 mM NaCl). The formulated nanoemulsions showed slight change in d4,3 during 15 days of storage at 5, 25 and 40 °C. However, the chemical stability strongly depended on the storage temperature, with the lowest level of AST retained in nanoemulsions stored at higher temperature.