| Maize silk (Stigma maydis) is dried stigma and silk in maize (Zea mays L.), which is in record of the first section of ? The People's Republic of China's Herb Dictionary? (version 1977 as a variety). Its functions of decreasing turgescence and decreasing blood pressure were known commonly. The maize yield is the 20% of the cereal yield in China, which come second of the world in the corn yield. There are approximately 23.3 million ha of maize in China. The yield of maize silk is estimated around 3.75 million kg. Stigma maydis is very rich in resource, cheap and easy-collecting medical material, and has been used in clinic recently years. The experiment results showed that it has obviously effects on curing hypertension and diabetes. However, the systematical study on the chemical component and pharmacology function of sigma maydis has not been reported. Every year the majority of maize silk was discarded as trash and has not been gotten to use worthily. The further research on the chemical component and pharmacological function of stigma maydis may accelerate the development of exploitation of stigma maydis resource. And also, there must be a huge economic benefit and an enormous social benefit. Therefore, we have studied the following several aspects on the chemical component and pharmacological function of stigma maydis. Here, I present some results on our research.1. The extraction with ultra sonication, organic* solvent extraction, resin absorption, polyamide chromatography and silica gel chromatography chemical extracting and isolating method were used in the experiment. Seven chemicals, they are alkaloid, flavonoid, organic acids, and a mixture were obtained and identified.2. The HSCCC instrument was at the first time used to isolate and to purify flavonid from stigma maydis. A appropriate organ solvent system (CHCl3: MeOH: nBuOH: H2O=7:6:1:4) was identified. Two flavone glycosides with their purity over 99.9% were obtained.3. Agilent 1100 model high performance liquid chromatograph instrument, ZORBAX semi-preparative column (250x9.4mm) and YMC half preparative coloumn (250?.4mm) were used in this experiment at the first time to isolate and to purify flavonoid component from stigmaIVmaydis. The optimum isolation conditions were found. They were follows:The wavelength was at 340nm, the column oven temperature was at 30C, the injection volume was 0.5ml, the flow rate was at 3.0mL/min, the isocratic flowed is 22% methanol/water for 26 minutes. And the linear solvent gradient flowed is from 22% methanol/water to 50% methanol/water for 114 minutes, from 50% methanol/water to 100% methanol/water for 10 minutes, and from 100% methanol/water to 22% methanol/water for l0minutes. Seven flavone glycosides and one peptide were obtained.Eleven flavonoid included 5-OH-4'-OCH3-6-c-rhu, 7-O-glu-acacetin (1); 5,7-di-OH-3'--OCH3 -6-c- (2-O-glu)- rhu-flavone (2); 5,7,3'- tri-OH, 4'- OCH3 -2,6-C-di-glu-flavone glycoside (2,6-C-di-glu-genkwanin 3); 5,7,3'-tri-OH,-2-c- rhu-6-C-glu - flavonoid glycoside (2-c- rhu-6-C-glu-apigenin 4); 5,7,3'-tri-OH,4'- OCH -2,6-C-di-rhu flavonoid glycoside (2,6-C-di-rhu-genkwanin 5); 5,7,3-- tri OH,-6-c-glu ,-8-C-glu - flavonoid glycoside (6-C, 8-C-glu -apigenin 6); 5,7,3- tri-OH,4' OCH -2-C- glu,6-C-rhu - flavonoid glycoside (2-C-glu,6-C-rhu-genkwanin 7); 5,7,3 tri OH,-2-c-glu ,-6-C-rhu - flavonoid glycoside (2-C-glu, 6-C-rhu -apigenin 8); 5,7,3 tri OH,-6-c-rhu ,-8-C-rhu - flavonoid glycoside (6-C, 8-C-rhu -apigenin 9) luteolin (10), and apigenin (11) were isolated from stigma maydis at the first time by using data of physical constants, chemistry evidence and spectrum analysis methods( MS, IR, UV, NMR ).4. The methods of isolating and determining chlorogenic acid of stigma maydis were established in the experiment; the three maize varieties contained high levels of chlorogenic acid were sifted from sixty two maize varieties. This provided the chemical basis for the maize breeding on the natural resistance corn worm resource in China. By comparing the result of chlorogeni...
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