Study On The Isoaltion, Purification, Identification And Contraception Mechanism Of Antifertility Bioactive Component From Neem Oil

The effective control of mice is of importance to ensure the agriculture sustainable development. Presently, most of the rodenticides mainly cause the increase of the mortality of mice and could not keep long effect, the low density of mice can maintain only one year, since the density of mice rise gradually and restore to the previous level. Due to the shortcoming of traditional rodenticide, the new rodenticide is urgently necessary for the efficacious and continuous reduction of mice: the population density of mice could be reduced by decreasing the reproduction rate of mice, namely, developing a new strategy of biological sterilization of mice. The aim of this paper is to explore a plant rodenticide to control the birthrate of mice, proper dosage can cause male mouse yeld , have a long-term effect and is harmless to human, animal and environment.Neem oil, also called Margoaa oil, an extract from the seeds of Azadirachta indica, have strong killing-sperm effect, the contraception effect is 100% to human and monkey. To develop a new sterilities and using Azadirachta indica A.Juss, theexperiment was conducted to study the extraction, isolation and identification, the contraception mechanism and the security to mammal of the antifertility active components from neem oil; To enhance the edibility and test the practical effect, the antifertility active components were embeded with microcapsule. The results could promote the elucidation of antifertility effect mechanism on diversified levels and development of promising new biorational rodenticide from the neem oil; It will be helpful to evaluate the antifertility value of neem oil, to search the effective and low toxic antifertility substance to protect environment and control the mice calamity of grassland. The main results are showed as follows.1. Neem oil A is a natural product extracted from Neem oil, and the component is separated by systematic extraction, Chromatography, re-crystal method , and the structure of antifertility bioactive component was determined by IR,UV,NMR and EI-MS as 2-Octadecanoic acid-4-Palmitic acid-2, 4-Pentanediyl ester. Its yield rate was 0.31%,the concentration of killing-sperm in vitro was 2mg/ml/20s. The results revealed that the antifertility activity was present in constituents of intermediate polarity, and for the first time the antifertility bioactive component was separated from Neem oil which could be utilized to develop a new spermicidal medicine.2. Kunming mice orally received the chloroform extracts of neem oil 2g/kg.d for one week, after the third week after administration. The mice were taken to study the antifertility effect on different levels, such as the animal reproduction test, hormone and blood biochemical analysis, cell and sub-cell structure and molecule level.The results were found that the chloroform extracts from neem oil had positive ant fertility effect, the rate of contraception is 100% and the infertility could be maintained for six months which was reversible in 7-12 months after administration. The biochemical indexes initially decreased and then gradually restored to normal level in the blood of the treated mice, suggesting that the bioactive component from neem oil had no obvious side-effect on mice. Serum testosterone levels did not evidently changed, but the total concentration of amino acid of testicle tissue decreased by 7.09%. Light microscope observation revealed that the testis shrunkentubules and germ cell differentiation were disorganized and suppressed, and macrophage cells increased, sperm concentration diminished to zero in the epididymis with no obvious change in the epithelium. The electronic microscopy examination indicated that after administration, the acrosome and karyotheca of spermatids were obviously damaged in different eroded deletions in the small or large areas at the edge of the cytoplasm membrane; In some cases, more serious damages in the cytoplasm of sperm were observed, for example, the membrane damage, granular degeneration, dissolution, vacuolization were very signi...