Elementary Study On The Exploitation Of Protein Feed With Dendrolimus Punctatus Walker

Dendrolimus spp. is one of the most serious forestry insect pests in China. That how to manage it effectively, up to now, is still a task for us to do though the research on it has been undertaken for many years. In this paper, the pest is taken as a kind of resource to us, and the value of its nutrition, the exploitation of the protein and the toxin in its body are studied. The results of nutrition assay show that there are plenty of proteins in the body of adult, larva and pupa of Dendrolimus punctatus Walker. Among them, the content in adult is the highest, it is 72.07%, and the content in larva, 67.17%, is higher than in pupa that is 50.0 1%. There are fifteen kinds of amino acid in the body of Dendrolimus punctatus Walker (Tyr. is not analysed), and the content is 46.00 %. The content of the fat and carbohydrate in pupa is the highest of all, the fat content is 25.02% while the carbohydrate content is 8.51%. The fat content and carbohydrate content in larva is 15.05% and 3.64%, and they are 9.20% and 3.21% in adult. there are also ample minerals in the body of Dendrolimus punctatus Walker, especially sodium (Na), calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn), manganese (Mn) and cuprum (Cu). The contents of sodium (Na), zinc (Zn), manganese (Mn), magnesium (Mg) and cuprum (Cu) are higher than those in the body of other common edible insects. The experiment results of toxin in the body of c show that the active components of the toxin could be melted, easily in alcohol, generally in n-butanol and less in distilled water and n-hexane. The result of the acute toxicity test shows that the toxicity of the alcohol extraction is not high because its LD50 is more than 1,160mg/kg. The result of rabbit skin experiment shows that it is less possible that there are any proteins in the toxin, and the active components of the toxin is not steady to the heat produced by the treatment of 105 C. The proteins in the body of Dendrolimus punctatus Walker are extracted by three different solvents, buffer solution, weak salt solution and weak alkaline solution. The results show that the extraction efficiency of buffer solution, 60.361.25%, is the highest of all while the extraction efficiency of weak alkaline solution is 50.27 2.00% and it of weak salt solution is 37.53 0.50%. The best conditions of extraction tested by the experiments are as follows: The buffer solution is Na2HPO4- NaOH(0.OSmol/L Na2HPO4, 0. lmol/L NaOH), raw materials should be powder,materials to solution is l to 20(w/v), the pH of extraction is 9.5, the time of extractionis 3h and the temperatUre is 40' C. The pH of subsidence is 5.5, the temperature of it is5' C and the time is lh. With these conditions, some proteins are extracted. The proteincontent in them is 7l. l2 l0. l6%, and the total extraction rate of nitrogen is 60.36 tl .25%.