Abstract:

The aim of this study was to better exploit and utilize silkworm faeces, and provided experimental data and theoretical basis for industrial production of chlorophyll from silkworm faeces. Silkworm faeces as raw material, chlorophyll was prepared with mixture solution of acetone and ethanol (2:1) using the method of ultrasonic-assisted organic solvent extraction in this study. The influences of main process parameters, including ratios of solid material to solvent volume, softening time, ultrasonic temperatures and ultrasonic time on chlorophyll extraction efficiency from silkworm faeces were compared and analyzed, moreover, the extraction process was optimized via single-factor tests and a four-factor three-level orthogonal array experimental design (L9(34)). The results showed that the method of ultrasonic-assisted organic solvent extraction was an effective and practicable one for chlorophyll extraction from silkworm faeces. The most suitable conditions for chlorophyll extraction from silkworm faeces were as follows: ratio of solid material to solvent volume was 1:200 (g/mL), softening time was 10 min, ultrasonic temperature was 50℃ and ultrasonic time was 60 min. And the concentration of chlorophyll a reached 13.825 mg/L when the optimal conditions were met. Therefore, the ultrasonic-assisted organic solvent extraction process was with easy operation and high safety, low cost, high product quality, and provided reference value for further industrial production of chlorophyll from silkworm faeces.