The Establishment Of Three Kinds Major Economic Crabs Phospholipid Fingerprint

In recent years, economic crab aquaculture in our country has been in the growth development. At the same time, our country’s crab production accounted for the proportion of world output has also been improved. Blue crab, mud crab, flower crab and Chinese mitten crab have the characteristics of fast growth, fresh meat, high edible value and high economic benefit. The above four reasons make them become the main economic crab in our country. Economic crabs contain rich unsaturated fatty acid, including eicosapentaenoic acid(EPA) and docosahexaenoic acid(DHA).These two kinds of unsaturated fatty acids have many functional activities, including the prevention and treatment of some diseases such as: cardiovascular, cancer, fatty liver, high blood lipids; and anti cancer, anti ageing, promote the normal growth of human body. Crab contains abundant phospholipid source. Phospholipid is a special lipid containing phosphoric acid, which is a basic component of the cell membrane and nuclear membrane and have special nutritional and medical value. Meanwhile, phospholipid is also an important material in the metabolism process, some phospholipids can be used as biomarkers of certain diseases. So the research of the phospholipid in crabs has important significance.First of all, using chloroform methanol method determination of three economic crabs total fat content in muscle and liver pancreas. Experimental results show that the content of total lipid in hepatopancreas was significantly higher than that in muscle, and the total lipid content of mud crab muscle was the highest in the three kinds of crab, so it has a good taste of meat. The muscles in the total fat content is between 3.9% and 4.4%, total fat content in hepatopancreas between 8.1% and 8.6%. In order to explore whether the higher total lipids means river crab is more nutritious than the sea crab, we determined the content of phospholipid. Results show that the phospholipids content of total fat in the four kinds of crab muscle significantly higher than the content in hepatopancreas, it shouws that the phospholipid content in muscle is higher, and phospholipids in hepatopancreas lipids accounted for only three.By comparison, the phospholipid content in mud crab was highest in the three kinds of sea crab, high phosphatide content makes mud crab more nutrition and health.By using positive phase hexane- isopropyl alcohol- amine acetate buffer as eluent and analysed by using high performance liquid chromatography(HPLC). The results show that the phospholipid in Portunus trituberculatus, Scylla serrata, Portunus pelagicus is mainly composed of PC, PE, PI, the total content of 94% or more. In the composition of muscle phospholipid components on the structure, the structure of mud crab is the most excellent. Comprehensive comparison, Eriocheir sinensis PC, PE, PI value is much less than sea crab, this shows that the high-quality phospholipid content in it are lower than the sea crab.The content and proportion of phospholipid in crabs are different, each crab phospholipid composition is unique, in the establishment of phospholipids can be used as the characteristic index of fingerprint.Secondly, in order to analyze total lipid and fatty acid composition of phospholipids in four kinds of crab, identifying 22 kinds of fatty acids in total lipids and 16 kinds of fatty acids in phospholipid by using GC-MS. By comparison, the proportion of palmitic acid content of three kinds of crab were less thanhalf of Eriocheir sinensis while EPA and DHA in sea crab were higher than those in Chinese mitten crab which shows that nutrition value of sea crab is slightly higher than that of Chinese mitten crab. Scylla serrata have the highest proportion of PUFA(PL) and more active in the oxidative stability and speed of thedigestion and absorption. Total lipid and phospholipid fatty acid composition in different crab has the difference, in the establishment of phospholipid fingerprint can be selected as characteristic index.Finally, by C20:5n-3、C22:6n-3、C16:0、C18:1n-9、C18:2n-6、C18:3n-3、、C20:5n-3(PL)、C22:6n-3(PL)、C16:0(PL)、C18:1n-9(PL)、C18:2n-6(PL)、C18:3n-3(PL)、PC、PE、PIcharacteristics of the 15 indexes to establish Portunus trituberculatus, Scylla serrata, Portunus pelagicus phospholipids fingerprint, it can see the accurate total lipid and phosphatide content in different crabs and the mutual relationship, and these improve the nutrition of aquatic products of basic information. And through the included angle cosine method and correlation coefficient method can compare phospholipid fingerprint evaluation of genetic relationship of different crab, offers an efficient method for identification of common edible crab.The sixth chapter add temperature and time factors to verify crab phospholipid fingerprinting. Selected the blue crab in 9, 10, 11, 12 month for total lipid and phosphatide composition and composition analysis, by increasing the different environment and temperature factors, we can get four months of phospholipid fingerprinting. Four phospholipids fingerprint correlation coefficient in 0.989 to 0.996, a high similarity. This shows that the blue crab phospholipid fingerprint set up with stability and reliability through the 15 characteristics which is C20:5n-3 、C22:6n-3、C16:0、C18:1n-9、C18:2n-6、C18:3n-3、、C20:5n-3(PL)、C22:6n-3(PL)、C16:0(PL)、C18:1n-9(PL)、C18:2n-6(PL)、C18:3n-3(PL)、PC、PE、PI. Through the analysis of different month blue crab phospholipid fingerprint, we can get the content of main nutrients and functional material of different month blue crab. It shows that the blue crab phospholipid fingerprints can provide the main phospholipids and fatty acid information.This study uses the sample capacity is small. So this study is the preliminary study stage, also need to gradually increase the number of samples in the future research, in order to improve the accuracy of the phospholipid fingerprint, minimize the impact of environmental factors, climate factors and feeding conditions. In the future, we can through this method to further understand the main economic crabs phospholipid composition of chemical information and provide a theoretical basis of nutritional evaluation of phospholipids on main economic crabs.