Application of lutein in aquatic feed

According to the China’s Catalogue of Additive Varieties (2013), yellow pigment is specifically used for aquaculture animals must be natural leaves sourced from marigold flavonoids products. Natural lutein (derived from marigold) products have formed a complete industrial chain which widely used in poultry feed and aquatic feed, as well as for food additives and health products

Marigold extract, the effective ingredients are lutein and its isomer zeaxanthin

What are the functions of natural lutein in aquatic animals?

The first function is the coloring function.

Natural lutein is orange yellow with a bright color and strong coloring ability. It is currently widely used in coloring the skin, egg yolks, and shins of poultry. Due to the inability of animal bodies to synthesize lutein on their own, they can only digest and absorb lutein and its esters from feed for their own pigment deposition needs. After transfer and esterification of fatty acids in the body, they ultimately deposit in subcutaneous fat, egg yolk, and tibia tissues. In aquaculture, the main utilization is the coloring function of natural lutein.

The second is antioxidant function

Natural lutein has strong antioxidant function and can inhibit reactive oxygen species

The activity of radicals prevents the damage of reactive oxygen species to normal cells.

It has been verified that reactive oxygen species can react with DNA, proteins, and lipids,

weakening their physiological functions. Lutein can inactivate singlet oxygen through physical or chemical quenching, thereby protecting the body from harm and enhancing the body's immune system

Thirdly, other biological functions

In the aquaculture of aquatic animals, lutein not only plays a coloring and antioxidant role

But also plays role of transformation, as well as many other biological functions: as a fertilization hormone,good egg quality; Enhance immunity, promote growth and maturation; Enhance fish body's resistance to high ammonia and low oxygen tolerance; As a precursor of vitamin A; Aquatic animal lipid peroxidation reaction;appropriate inhibitors; the protective effect against ultraviolet radiation.During the breeding season, mature male fish concentrate lutein on their skin, forming their second sexual characteristic - marital color; And the females concentrate in the ovaries, forming a protective color for the juveniles.

Color is one of the important indicators of aquatic product quality, and the deposition of color often represents the wild time limit of fish, and its bright color often makes people judge aquatic products.The standards for product quality and flavor will also increase the market price. Aquatic animals themselves cannot generate lutein and must be taken from food.However, the lutein content in aquatic compound feed is relatively low, and the breeding cycle is short, which makes it difficult for aquatic animals to obtain sufficient lutein, resulting in a deterioration of their body surface or muscle color.

At present, natural lutein has been found in yellow catfish, bearded catfish, bigmouth catfish, and large mouth catfish。Research has been conducted on special farmed fish such as yellow croaker and shrimp, and has been successfully applied to many yellow species such as yellow catfish, bearded catfish, bigmouth catfish, and golden pomfret (ovoid pomfret)special features include scad, yellow croaker, loach, eel, turtle, eel, frog, etc.Planting economic aquatic animals and successfully applying to South American white shrimp, Chinese mitten crab, in crustaceans,etc. The amount of natural lutein added to various feeds is 30-80 mg/kg, and the specific amount depends on the breeding stage, coloring time, and feeding amount.

Different types of feed ingredients result in varying levels of lutein content; The content of lutein in feed raw materials of the same type but different batches also varies, and the content of lutein will change during processing and storage.

In addition, factors such as feeding methods, water temperature, and light can also affect the coloring effect of aquatic animals.

In short, natural lutein (derived from marigold) can meet the color matching needs of yellow farmed fish and crustaceans, and is safe and green; Natural lutein also has strong antioxidant capacity, which enhances the immune function of aquatic animals; More importantly, natural lutein (derived from marigold) has achieved a full industry chain in China, including marigold seed selection, marigold cultivation, and deep processing of lutein. With abundant sources and excellent cost-effectiveness, it has great value in aquaculture