Abstract:

This study was carried out with a view of determining the optimal conditions for extracting proanthocyanidins
from F. altissima fruits by combined use of single factor and orthogonal array designs. The effects of solvent type and
concentration, extraction time, solid/liquid ratio, pH and temperature on the extraction rate of proanthocyanidins were
investigated. The extracted proanthocyanidins were assayed by colorimetry using n-butanol:hydrochloric acid at a
wavelength of 546 nm. The results showed that the optimal extraction conditions were found to be extraction at 40 ℃
for 1 h using 80% ethanol acidified to pH 3 with a solid/liquid ratio of 1:15, and the effect of four important variables
on the extraction rate of proanthocyanidins followed the decreasing order: solid/liquid ratio > extraction temperature >
ethanol concentration > extraction duration. By repeating the optimized extraction procedure five times, the content of
proanthocyanidins in F. altissima fruit was measured to be 13.05% and the extraction rate of procyanidins was 91.46% after
the second extraction.

Key words: Ficus altissima, fruit, proanthocyanidins, extraction