Improvement on Extraction of Chlorophyll and Synthesis of Pheophorbide from Silkworm Excrement

OBJECTIVE To explore the influence of different extraction technologies on the extraction of chlorophyll and chlorophyll derivatives from silkworm excreta in order to improve the yield. METHODS The extraction technology of chlorophyll from silkworm excrement was optimized with softening time and different solvents using single factor experiments design. The effects of magnesium removal time with hydrochloric acid on yield of pheophorbide from chlorophyll have been investigated. RESULTS In the present study, the optimized extraction technology of chlorophyll from silkworm excrement was as follows: the softening time of silkworm excrement was 2 h (26% of water content), and the extraction solvent was 1∶1 of acetone∶ethanol. The production rate of chlorophyll was 1.43%. The preparation parameters of pheophorbide from chlorophyll were removing magnesium with hydrochloric acid for 72 hours. The yield of pheophorbide was 670 mg·g^-1. CONLUSION The rate of production of chlorophyll and pheophorbide from silkworm excrement has been increased by improving extraction technology.