Studies On Chemical Components And Biological Activities Of Jellyfish(Rhopilema Esculentum Kishinouye)

Rhopilema esculentum jellyfish, a species of large and edible jellyfish, having the higheconomic and nutritional value, is a big and important fishery resource in China. The jellyfishhave long been recognized to have some medicinal functions. It is believed to be an effective curefor hypertension, chronic tracheitis, asthma, gastric ulcer and struma. Considering its nutrient andcurative value, R. esculentum jellyfish should be further investigate and exploited for its chemicalcompositions and pharmacological characters. However, because fresh jellyfish contain highmoisture content, easily decompose and dissolve itself, little information has been published onutilization of jellyfish for human consumption. In this dissertation, fresh R. esculentum jellyfish captured in Yellow Sea near Qingdao cityand cured R. esculentum jellyfish purchased from a local market were selected as experimentalmaterials, and they were divided into the umbrella, oral arms and goad tissue after obtained. Thechemical components of them were separated and analyzed, and some studies on their bioactivitieswere conducted according to different requirement. The main inorganic elements and contents ofR. esculentum jellyfish existed largely in Chinese sea aera were determined for the first time byadvanced analysis technique and instrument. The analysis methods for the determination of microor trace elements in high moisture jellyfish were developed. The fatty acid compositions indifderent parts of fresh jellyfish were determined by GC/MS method. Thirty-five fatty acids wereidentified, and most of them were found in R. esculentum jellyfish for the first time. Especially,two unusual very long chain polyunsaturated fatty acids that were never detected in the otherjellyfish also were determined. Amino acids were abundant in R. esculentum jellyfish, especiallycontaining sulfur amino acids, and could be supplied for human diet. The polysaccharide inumbrella part of jellyfish was composed of glucose, galactose and uronic acid, and its molecularweight was 40,000, but the polysaccharide of the oral arms part consisted of glucose, mannose andglycuronic acid, and its molecular weight was 43,000. Above-mentioned data were never reported.The ethanolic extract of oral arms part of jellyfish were extracted by different polar solvents(petroleum ether, acetic ether, n-butanol), and antibacterial activity was tested to these extracts byfour species of terricolous pathogenic bacilli and three species of botanic pathogenic fungi. Theresult demonstrated that the petroleum ether extract had certain bactericidal activity for twospecies of pathogenic bacilli, and n-butanol extract had certain inhibited activity on apple rotpathogenic fungus (Valsa mali). The solvent extracts were analyzed by gas chromatography –mass spectrometry (GC/MS), and seventy compounds were identified. Most of them were foundin jellyfish for the first time. The in vitro scavenging activities of two polysaccharides of jellyfishon superoxide radical, hydroxyl radical and DPPH, and their protective effects on H2O2-inducedhemolysis of rat erythrocytes and lipid peroxidation of liver homogenate in rat were alsoinvestigated, and results showed that both of the polysaccharide samples had strongly scavengingeffect on superoxide anion radical and hydroxyl radical. Some progress in study on R. esculentum jellyfish have been made in this dissertation, and asolid theoretical foundation has been established to exploit and utilize jellyfish resource. Study onjellyfish's medicinal function, such as cure for hypertension, cancer, inflammation and asthmashould be enhanced by combination with traditional Chinese medicine theory, which willcontibute to jellyfish's application in medicine field.