Abstract:

This study was undertaken to optimize the extraction of proanthocyanidins from flowers of Cinnamomum
burmannii. The starting raw material, freeze-dried flowers of Cinnamomum burmannii ground and sieved through a 80-
mesh sieve, was extracted using acetone-ethanol and the extract was submitted to color development catalyzed by iron salt
before measuring the absorbance. Five extraction conditions including extractant concentration, pH, solid-to-solvent ratio,
temperature and time were optimized by one-factor-at-a-time and orthogonal array design methods. The optimal extraction
efficiency was obtained by three repeated cycles of extraction at 50 ℃ for 2 h using an extractant consisting of 70% acetoneethanol
in water, as prepared by mixing 70% acetone and 70% ethanol with a volume ratio of 3:2, with a solid-to-solvent
ratio of 1:7.5 (g/mL). Under these conditions, the proanthocyanidin recovery was 95.37%, and the proanthocyanidin
content in dried flowers of Cinnamomum burmannii was 9.02%. Thus acetone is an effective solvent for extracting
proanthocyanidins from flowers of Cinnamomum burmannii under optimized conditions.

Key words: flower of Cinnamomum burmannii, proanthocyanidins, extraction process