关键词: 超临界CO₂, 纤维素酶, 落叶松树皮, 原花青素, 提取工艺

Abstract: The supercritical fluid extraction combined with enzymatic hydrolysis technology for extracting proanthocyanidins from the larch bark was studied. Firstly, lipophilic components from the larch bark were extracted by supercritical CO₂ at 50 ℃ for 130 min (extraction pressure was 35 MPa), and the average extraction yield of grease was 2.16%. Then proanthocyanidins were extracted from the raffinate with cellulase-assisted. The optimum extraction condition, through the single factor and orthogonal test to determine were as follows:3 g degreased bark powder, Buffer solution as the solvent, the material for the granularity of the raw material 150-178 μm, 0.6% of raw material quality as the amount of the fiber enzyme addition, the liquid-solid ratio 14:1(mL:g), the pH of enzymatic hydrolysis 5, the enzymolysis temperature 40 ℃. After enzymolysis 2 h, the yield of proanthocyanidins can reach 7.36%. The analysis showed that the fiber structure of bark had been damaged with different degrees after the extraction with cellulase-assisted methods by SEM and FT-IR. And hence this facilitated mass transfer and promoted extraction efficiency. The structure unit of procyanidins type is confirmed mainly in the proanthocyanidins molecule of the larch bark. The structure of efficient component was not changed.

Key words: supercritical CO₂, cellulase, larch bark, proanthocyanidins, extraction