低共熔溶剂提高积雪草有效成分提取效率的研究

Improving extraction efficiency of active ingredient from Centella asiatica by deep eutectic solvents

本研究采用低共熔溶剂法提取积雪草中有效成分,通过气相色谱法分析馏出液中β-石竹烯的浓度;采用高效液相色谱法分析水提取液中羟基积雪草苷和积雪草苷的浓度,并计算得率;检测积雪草提取前后纤维素、半纤维素和木质素的含量,并且采用扫描电镜进行组织结构形态观察。结果显示:(1)低共熔溶剂法馏出液中β-石竹烯的浓度为6.58μL·mL-1,较水蒸气蒸馏法提高6.15倍;(2)低共熔溶剂法提取羟基积雪草苷和积雪草苷得率分别为1.03%和0.89%,分别较水提取法提高1.40倍和3.68倍;(3)低共熔溶剂提取后的积雪草渣中纤维素、半纤维素和木质素含量分别较原料下降61.39%、59.19%和59.33%,而水蒸气蒸馏法仅下降31.29%、12.43%和2.30%;(4)低共熔溶剂提取后的积雪草渣中的组织结构破坏程度较水提取更严重。由此可知,低共熔溶剂可显著提高积雪草中有效成分的得率,其作用机制是通过溶解植物体的纤维素、半纤维素和木质素,破坏植物组织结构,从而促进有效成分溶出。研究成果为高效提取积雪草工艺提供了研究基础。

In this study, the deep eutectic solvent was used to extract the active ingredient of Centella asiatica. The concentration of β-caryophyllene in the distillate of Centella asiatica extracted was analyzed by gas chromatography. The concentration of hydroxyasiaticoside and asiaticoside extracted was analyzed by high performance liquid chromatography, and the yield was calculated. In accordance with the relevant national standards, cellulose, hemicelluloses, and lignin were determined. Morphology of Centella asiatica was observed by scanning electron microscopy before and after extraction. Several results were shown as follows:(1) The concentration of β-caryophyllene in the distillate of eutectic solvent was 6.58 μL·mL-1, which was 6.15 times higher than that of steam distillation.(2)The yields of hydroxyasiaticoside and asiaticoside in water extract of eutectic solvent were 1.03% and 0.89%, which were 1.40 and 3.68 times higher than that of water extraction, respectively.(3) Compared with the raw materials, the contents of cellulose, hemicelluloses, and lignin in Centella asiatica residue extracted by eutectic solvent were decreased by 61.39%, 59.19%, and 59.33%, respectively, while those via steam distillation were decreased by 31.29%, 12.43%, and 2.30%, respectively.(4) Scanning electron microscope observation were shown that the damage of tissue structure in Centella asiatica residue extracted by eutectic solvent was more serious than that by water extraction. The extraction efficiency of β-caryophyllene, madecassoside, and asiaticoside from Centella asiatica was improved by deep eutectic solvent, and the mechanism was shown that plant tissue structure was destroyed and cellulose, hemicelluloses, and lignin were dissolved, promoting dissolution of effective components. The research results provided basis for the extraction technology of Centella asiatica.