Abstract:

In this study, the response surface methodology and full factorial design were employed to evaluate the
extraction efficiencies of Myrica rubra kernel oil by aqueous enzymatic extraction with three individual enzymes and their
combinations, and it turned out that cellulase was the best enzyme for the extraction of Myrica rubra kernel oil. Then, using
an orthogonal array design, the optimum hydrolysis conditions for oil extraction were determined as follows: cellulase dose,
2%; temperature, 50 ℃; pH value, 4.8; time, 2.5 h; and solid/liquid ratio, 1:4 (g/mL). Under these conditions, the oil yield
was 33.95%, which was 50.67% as compared to the oil content of Myrica rubra kernels measured according to the Chinese
national standard GB/T 5512—2008. Gas chromatography analysis revealed that the kernel oil contained 87.22% unsaturated
fatty acids, including 50.31% oleic acid, 36.64% linoleic acid and 0.27% linolenic acid.

Key words: response surface methodology, aqueous enzymatic extraction, Myrica rubra kernel oil, oil yield, fatty acid