Gastrodia elata is a plant belonging to orchidaceae family whose root and leave are degenerated without the ability to carry out photo synthesis,but can grow and develop with Armillaria mellea by symbiosis. Its cycle of growth and development from seeds to seeds is much changable under artificial control. Our previousexperience on the sexual propagation of the plant in Guizhou showed that two to four years are needed for its growth and development. It is now found that the cycle can be shortened to two years in the greenhouse partly through breeding and artificial pollination for mature fruit and plumpy seeds and partly through reasonable designing and sowing half a month in advance. So G. elata can be available on the market one or two years earlier.

AIM: To find the optimum extraction of volatile oil. METHOD: To extract the volatile oil by steam distillation or supercritical fluid extraction (SFE). RESULT: (1) The optimum extraction of volatile oil extracting by steam distillation is: Ligustricum Chuanxiong Hort.:Soak time 12 hrs, thin powder, extract time 3hrs, and to add water with 1∶10; Alpinia Officinarum Hance: Soak time 0 hr, thick powder, extract time 3 hrs, and to add water with 1∶10; Curcuma Wenyujin Y.H. chen C. Ling: Soak time 24hrs, mild powder, extract time 1.5hrs, and to add water with 1∶5; Notopterygium incisum Ting: Soak time 0 hr, thick powder, extract time 3 hrs, and to add water with 1∶10. (2) The best condition of volatile oil extracting by SFE is: Ligustricum Chuanxiong Hort.: 60℃, thin powder, press 25MPa, extract time 1.5hrs; Alpinia Officinarum Hance: 60℃, mild powder, press 25MPa, extract time 0.5hr; Curcuma Wenyujin Y.H. chen C. Ling: 60℃, thin powder, press 20MPa, extract time 1 hr; Notopterygium incisum Ting: 60℃, thin powder, press 25MPa, extract time 1hr. CONCLUSION: Supercritical fluid extraction (SFE) is superior to steam distillation.

A new approach based on online coupled liquid chromatography-gas chromatography-mass spectrometry ( LC-GC / MS ) was developed for the rapid determination of 4-( methylnitrosamino )-1-( 3-pyridyl)-1-butanone (NNK) in mainstream cigarette smoke, in which a switching valve was employed to online switching between two-dimensional chromatography. The online LC-GC / MS system used in this study was built by using online gel permeation chromatography-gas chromatography-mass spectrometry except that the micro gel column was replaced by micro alkaline alumina column which was prepared by ourselves before. The NNK in mainstream cigarette smoke was collected by a Cambridge filter pad, then the pad was extracted with dichloromethane, and the extract was quantitatively analyzed by online LC-GC / MS with D4-NNK as an internal standard. Online LC-GC / MS allowed online pretreatment purification, and the sample was subjected to online LC-GC / MS without any prior purification, which reduced human error in analysis process. The injection volume of the present online LC-GC / MS could reach 40 μL, which was 20 times of that of the conventional GC / MS (2. 0 μL of injection volume), and thus significantly improved the sensitivity. Under the optimum conditions, good linearity ( r = 0. 9998) was obtained over the range of 1. 2 - 120 ng / mL. The recoveries at three spiked levels ranged from 93. 9% to 96. 0% , and the limits of detection for qualitative and quantitative detection were 0. 25 ng / mL and 0. 9 ng / mL, respectively. All the results obtained by the present method are comparable to those of standard method recommend by China National Tobacco Company.