| Menopause women are easy to sicken for kinds of syndromes such as osteoporosis and blood vessel disease because of weakened ovary function and estrogen's insufficiency. Estrogen replacement therapy can mitigate the Menopause syndrome. Although estrogen can protect cardiovascular system by reducing the rate of cardio-vascular disease through regulating smooth muscle strain and lipid metabolize, there is great side effect showing the risk of endometrial cancer and breast cancer occurrence increased after taking estrogen for a long time. Phytoestrogens such as isoflavones, which originates from plant and has similar structure to mammalian estrogens, can weakly bind to estrogen receptors and show either estrogen-like effects or anti-estrogenic effects on the target tissues. They can selectively bind to estrogen receptor (ERαandβ), inhibit the occurrence of endometrial cancer and breast cancer while mitigating the menopause syndrome. Research in this area for mankind to find effective and safe natural estrogen replacement drugs provided new clues and ideas. Isoflavones are existed in large amounts in soybeans, however, the use of planting resources as a phytoestrogens source not only need a large amount of farmland, but also have a longer period of plant growth cycle. Besides it also affected by geography, climate and other environmental factors. The use of plant cell culture technology to the production of plant metabolites can overcome these constraints and provide Human a new way to access to natural substances.In the present study, soybean callus was induced and cell suspension cultured line was established to expand the sources of phytoestrogens. Meanwhile, we studied the impacts of isoflavones synthesis precursor phenylalanine (Phenylalanine, Phe), secondary material effective elicitor methyl jasmonate (methyl jasmonate, MJ) , sucrose (Sucrose, S) and DMSO (Dimethylsulfoxide,DMSO) on the isoflavones accumulation in soybean suspension cells. Main conclusions are as follow:1. Soybean seeds, after disinfection, germinated and grew on medium without bacteria in order to obtain seedling from which the hypocotyls were induced into callus. Induction conditions: MS +2,4-D 0.8mg/L+ agar 0.8%, cultured in the dark with temperature (25±1)°C. Callus, white or light yellow, was induced in 15 days. Suspended cells system was established. Cotyledon explants from the seedling also was induced into callus. Induction conditions: MS +2,4-D 5.0mg/L+ sucrose3% + agar 0.8%; cultured in the dark with temperature (25±1)°C. Callus with white , light yellow , big or loose ,was induced in 5 days. Following the culture, we can also establish suspended cell lines.2. BA is not conducive to the formation of cotyledon callus; With its presence, the hypocotyl callus was induced with compact cells and rigidity tissues and not conducive to the formation of cell suspension.3. The isoflavones content of callus and suspension cells is higher than seeds. Total isoflavones content of suspended cells is approximately 4.88 mg/g, which is 3.15 times as that in the seeds.4. The optimal conditions of isoflavones accumulation in soybean suspended culture cells: MS +2,4-D 0.8mg/L+ agar 0.8%, cultured in the dark with temperature (25±1)°C and rotated speed 120r/min.5. DMSO can strongly stimulate the synthesis of isoflavones which can reach 7.54 mg/g at 48h. This content is 1.6 times as that in the cell suspension and 4.9 times in seeds; 45g/L sucrose is good for the accumulation of daidzein; 10umol/L Phe is conducive not only to daidzein accumulation but also to genistein accumulation at 48h. The content of genistein in regulated groups is 120% as that in control groups; 5umol/L MJ can promote soybean suspension cell to death and be not conducive to the synthesis of isoflavones.
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