A novel enzyme-assisted n-hexane/ethanol biphasic method to extract and separate heterotrophic Chlorella lipids for anti-inflammatory activity

Chlorella lipids are rich in essential fatty acids and have potential for development in food and healthcare products. This study established a novel enzyme-assisted biphasic extraction to obtain functional lipids from Chlorella sp. MBFJNU-17 biomass, and evaluated the anti-inflammatory function of the extracted lipids. The obtained results showed that the enzyme-assisted biphasic extraction mediated with pectinase and organic solvents (n-hexane and ethanol) achieved 17.3 % Chlorella cell wall disruption and 268.30 mg/g lipid extraction rate. After the optimization of this process, the n-hexane phase had 83.20 % neutral lipids (NLs), the ethanol phase contained 94.02 % polar lipids (53.65 % glycolipids (GLs) and 40.37 % phospholipids (PLs)), manifesting that the established biphasic lipid extraction exhibited the attracting feature to separate the NLs and polar lipids after lipids extraction. In term of the anti-inflammatory, the Chlorella polar lipids were found to perform superior anti-inflammatory effect with lower levels of inflammatory factors TNF-α and IL-6 than those of NLs. Compared to the lipids in the n-hexane and ethanol phases, three individual lipids (NL, GLs and PLs) performed poorer anti-inflammatory effects, indicating that the synergistic action could be effectively improved by the combination of three lipids. Taken together, the developed enzyme-assisted biphasic extraction method for Chlorella sp. MBFJNU-17 lipids was the potential lipid extraction process to concurrently extract and separate anti-inflammatory lipids. The study offered essential and scientific details to exploit high-value Chlorella lipids for nutritional and healthy bioproducts.