| Preparation of a new structured lipid（SL）containing ω-3 polyunsaturated fatty acids through immobilized lipase Novozyme 435 -catalyzed transesterification of Cinnamomum camphora seed kernel oil (CCSKO) and fish oil ethyl esters was investigated. The transesterification conditions were optimized using single factor experiment as follows: molar ratio of CCSKO to fish oil ethyl esters 1∶ 1, enzyme amount 10% (based on the mass of total substrates), reaction temperature 60 ℃ and reaction time 8 h. Under the optimal reaction conditions, the content of SL containing EPA or DHA was (24.34±033)%,and the enzyme maintained good stability. After a scale-up trial, the crude product was purified by a short path molecular distillation at 150 ℃ and the purity of SL was (44.22±057)%, the ratio of medium carbon chain fatty acids(MCFA) to long carbon chain fatty acids（LCFA） was 3∶ 1, and the contents of EPA and DHA were (11.91±0.44)% and (7.67±111)%, respectively. The triglyceride compositions of SL were mainly CC-EPA ((11.07±0.11)%), CC-DHA( (6.71±0.21)%), CLa-EPA ((7.78±0.51)%) and CLa -DHA （(5.99±0.25）%). The acid value, saponification value, iodine value and peroxide value of SL were(0.39±0.08)mgKOH/g,(250.31±1.02)mgKOH/g,(5487±0.86) gI/100 g and (1.12±0.01)mmol/kg,which met the national standards for edible oil product. The IC50 values of SL for scavenging DPPH free radical and ABTS free radical were (13.92±018)mg/mL and (8.99±0.05)mg/mL, respectively, indicating that SL had good antioxidant capacity. |
