关键词: 海参皂苷, 乙醇浓度, 料液比, 温度, sea cucumber saponins, ethanol concentration, material liquid ratio, temperature

Abstract: Sea cucumbers have long been used as a kind of food and traditional medicine in Asian countries. Stichopus hermanni, Thelenota ananas, Thelenota anax, Holothuria fuccogilva, and Actinopyga mauritiana are the main highly-valued species. Sea cucumber is rich in active substance such as triterpene glycosides, polysaccharide collagens and chondroitin sulfates. It is well known that holothurians are of high nutrition and pharmic values. Saponins are the main secondary metabolite of sea cucumber, and they are also the chemical basis for their defense. Sea cucumber saponins are composed of aglycone and sugar chain through β-glycosidic bond, mainly of holostane-type. Sea cucumber saponins are more polar, soluble in water, hot methanol, and ethanol. Moreover, there are many phospholipids in sea cucumbers, so alcohol extraction is generally used to remove fatty acids and save costs. At present, the extraction methods of sea cucumber saponins are mostly reflux extraction, alcohol-alcohol extraction, water extraction, and cold soak extraction. The separation and purification method mainly use a series of chromatographic techniques, such as macroporous resin column chromatography, dextran gel column chromatography, normal phase silica gel column chromatography, reversed phase silica gel column chromatography and HPLC. Pharmacological experiments showed that most of the sea cucumber saponins had strong physiological activities, including anti-tumor, anti-fungus, anti-radiation, hemolytic and anti-choline effects. Sea cucumber saponins was the main active substance of sea cucumber, which had great development value and potential application. In recent years, more and more researches on sea cucumber saponins have been carried out, and a variety of sea cucumber saponins have been gradually discovered. At present, at least 147 kinds of sea cucumber saponins have been isolated. But the content of sea cucumber saponins was low in sea cucumber. The metabolism process of sea cucumber is complex, the secondary metabolites in the body are abundant, and the sea cucumber saponins are more isomers, which bring great interference to the separation and purification and structural identification of saponin monomers, difficult to fully extract and analyze. In order to reduce the interference of polysaccharides and proteins in the preparation of sea cucumber saponins and simplify the subsequent separation process, the effects of ethanol concentration, temperature and solid-liquid ratio on the extraction of sea cucumber saponins were investigated. The results showed that the yield of sea cucumber saponins was higher when the concentration of ethanol was 0% and 80%, and the polysaccharide content in the extract was less when the concentration of ethanol was 0% and 80%, which was more conducive to subsequent separation; the saponins were more stable when extracted at 20 and 30℃, and less impurities when extracted at 30℃; and the content of sea cucumber saponins was higher when the ratio of material to liquid was 1:15, and the extraction time was controlled Impurities are produced and more saponins can be obtained. The results showed that when extracting sea cucumber saponin, it was extracted with 0% ethanol (pure water), the ratio of material to liquid was 1∶15, 20 °C, and the extraction time was controlled at 8 h, which could effectively increase the yield of sea cucumber saponin, control the generation of impurities, save extraction costs and simplify the separation and purification steps.