China is the biggest cotton country in the world, annual production of 6-7 million tons, 2006/07 of 6.73 million tons, cottonseed annual output is 9.6-11 million tons, 2006/07 of 11 million tons. Cotton seed contains cottonseed 50-55%, cottonseed oil content rate is 30 ~ 35% , cottonseed protein is 35 ~ 45%.
Cottonseed is not only a good oil resources, also is a kind of the main protein resources to be development. Cottonseed protein amino acid composition balance, close to the ideal model. However, has been due to the existence of the gossypol, cotton pulp content in the feed is restricted, moreover as a fertilizer fields.
Gossypol and its characteristics
Gossypol is a kind of peculiar to cottonseed non-ferrous toxic substances, have the rate 0.7 ~ 4.8% of the seeds. Gaa and class gaa concentrate in glandular cottonseed ball color, color gossypol gland is content of 20.6 ~ 39%, it is a kind of crystallized ginger, slightly acidic, melting point 181 ~ 185 ℃.
It is soluble in methanol, ethanol, isopropanol, acetone, ether, carbon tetrachloride and other organic solvent, can dissolve in oils and fats, insoluble in petroleum ether and water.
Gossypol in cotton seed cotyledons in the gossypol gland.Gossypol gland is a kind of tough Semi-solid, in the process of machining, it is difficult to be destroyed, in extracting cottonseed oil, because of the weather wet high temperature treatment, it is easy to be destroyed and make the gaa freed. Under certain conditions, the free gossypol can becomes modified gossypol or bound gossypol.
Gossypol acute poisoning typically occur within 0.5 h to 3 d after eating, the first symptom is the stomach heat, nausea, vomiting, abdominal pain, diarrhea, headache, lower limb paralysis, then an emergency coma, convulsions, stool, hematemesis, finally died of respiratory failure. Symptoms of chronic poisoning, the skin has a burning sensation, flustered, body tired weakness, thirst and want cold drinks.
