An overview of phospholipid and cholesterol nutrition of the pacific white shrimp, litopenaeus vannamei

摘要

Our knowledge of phospholipid, cholesterol and essential fatty acid nutrition has considerably advanced in the past couple of years with a number of significant publications in the area. This article reviews the advances in phospholipid and cholesterol nutrition of the Pacific white shrimp. The importance of phospholipids in penaeid shrimp nutrifion has been demonstrated by many researchers. They are major constituents of membranes and are vital to the normal function of every cell and organ. Phospholipids maintain cell structure and function, and have regulatory activities within the membrane and outside the cell acting as second messengers in cell signaling, an essential process in regulating cell growth, proliferation, differentiation, metabolism, nutrient uptake, ion transport, and even programmed cell death. In addition, phospholipids act as emulsifiers and facilitate the digestion and absorption of fatty acids, bile salts and other lipid-soluble matters. They also have a role in the transport of lipids, not only in the transport of absorbed lipids from the gut epithelium into the hemolymph, but also in the transport of lipids between tissues and organs since they are constituents of lipoproteins. Phosphatidylcholine (PC) is a particularlyimportant phospholipid because it is an essential component of such lipoproteins. Phospholipids also act as acyl donors for the lecithin cholesterol acyltransferase to convert cholesterol into cholesterol ester (Teshima 1997). Dietary phospholipids may serve as a source of choline, inositol, energy, and essential fatty acids (EFA). Consequently, the dietary requirement for these nutrients may be lowered if phospholipids are included in the diet. For instance, the efficiency of EFA supplied as neutral lipid could be improved by supplementing diets with phospholipids due to more efficient transport and better lipid mobilization from the hepatopancreas to the hemolymph and to other tissues and organs, resulting in enhanced lipid deposition and increased energy availability for growth (Teshima et al., 1986).