Abstract:

This study aimed to optimize the extraction of lycopene from Rhodobacter sphaeroides by response surface
methodology. With the extraction yield of lycopene per gram of cells as the response value, based on single factor
experiments, response surface methodology was used to explore the effects of saponification time, liquid-to-material ratio,
ultrasonic treatment time and extraction number as well as their interactions on the extraction rate of lycopene. As a result,
a regression model was established and the optimal extraction parameters were determined as 28 min saponification, 11 min
ultrasonic treatment and extraction performed twice using acetone as the extraction solvent with a material-to-liquid ratio of
1:86 (g/mL). Under these extraction conditions, the extraction yield of lycopene was 9 326.48 μg/g. The extraction method
developed in this study is feasible and will lay a foundation for further study of industrial production of lycopene by R.
sphaeroides fermentation.

Key words: Rhodobacter sphaeroides, lycopene, extraction, response surface methodology