【正文】 odulation and metabolic pathways may also be involved. Lycopene can be extracted from the sources it occurs naturally by different extraction processes. A number of processes have been proposed and are currently used for the extraction of oleoresins, by using hexane as the extraction solvent. The pulp obtained after the separation of waste materials and of tomato serum is fed to an extraction stage, where it is extracted to provide tomato oleoresin. Such oleoresin contains about 210% of lycopene, depending on the original concentration of lycopene in the tomato. However, evaporating organic solvent needs heating and Lycopene is thermally liable and also sensitive to light illumination. Supercritical fluid extraction, showing many advantages, has been widely used in many fields. Carbon dioxide, a most popular supercritical solvent,can be used to extract thermally labile materials because of its low critical temperature. Extracting lycopene from dried ripe tomato skins and seeds by supercritical CO2 has been carried out. It was found at low temperature, even with high pressure up to 27MPa, lycopene could not be detected in the extract. High enough recovery rate for lycopene could be obtained with temperature up to 80%. Entrainers such as chloroform may help enhancing solving power of CO2,but removing trace harmful entrainer from product is another problem. Xin Jiang, locating in China Northwest, has very special geography and weather conditions, which favor producing many kinds of nutrition rich fruits. A few kinds of tomatoes are believed in the rank of highest lycopene content in world. Tomato industry has been well established there. This work was aimed at a possible utilization of the byproducts of the tomato industry. In fact, the byproducts such as wastes from the production of peeled tomatoes and tomato concentrate could be an excellent source. Ropane, with mild critical temperature % and low critical pressure , having strong solving power for non polar or weak polar pounds,was considered a proper solvent for extracting lycopene. As well, extraction by SCCO2 was carried out as parison.1. Experiments Extracting lycopene oleoresins from tomato powders by propane were carried out in near critical and supercritical conditions with a 1L extractor instrument to search operating conditions for industrial pilot. The pilot is a selfdesigned multifunctional instrument with 600L solid extractors and 300L liquid extractor. During operation for solid matrix, feed is packed in the autoclaves, solvent propane was pumped and preheated to desired temperature and pressure to the extractor. The product oleoresin was separated from propane in solvent recovery tower. Remained solvent is further stripped by nitrogen in top product collector to obtain final product. And a bottom product may also be obtained when liquid feed is handled. High purity propane( wt%) was used，in which the only minorities are ethane and butane and no harmful substance exists. Supercritical CO2 extracting lycopene from tomato powders was carried out in an instrument with 2L extractor and pilot with 2*50L in Xin Jiang University. A HPLC method for lycopene analysis in oleoresins was established as described in. A supercritical fluid chromatograph (SFC) method was established as described in the proceedings. The HPLC method used mobile phase of methanol: THF: water=67:27:6 and Hpepersil BDS C18 (5181。) column with UVVis detection at 472nm. Both methods were found accurate. Figure 1 Schematic flowsheet of 3*300L pilot1N2, 2solvent cylinder, 3solvent level indicator, 4filter, 5 solvent pump, 6flow rate meter, 7preheater, 8solid extractor, 9liquid extractor with column, 10back pressure adjust system, 11 heater, 12solvent recovery tower, 13top product collector, 14cooler, 15bottom product coillector, 16liquid feed tank, 17liquid feed pump, 18thermal couple. 2. Results and Discussion At the beginning, tests were designed to find pronounced factors influencing SFE by CO2. Tomato powder size of 5, 20 and 60 mesh,extracting temperature of 30, 40 and 50% and pressure of 15, 25 and 35 MPa were chosen and cross bined. Table 1 illustrate that smaller powder size, higher temperature and pressure favor higher oleoresin yields. Small powder size will help overing mass transfer barrier while many researchers claimed there is no such barrier for SFE. The results show 60 mesh size,pressure at 35 MPa and temperature of 50% might be best binations. In subsequent experiments 60 mesh powder size was used for SEF by CO2. Figure 2 shows that oleoresin yield increases as pressure increase until 25MPa when extraction was carried out at 40% and run time . Further rising pressure will not get more oleoresin. Temperature was found having significant effect on extraction as shown in figure 3. Sufficient run time are necessary to obtain a plete recovery, see figure 4. In fact, the ratio of recycled solvent to feed (S/F) up to 90 (wt/wt) is necessary to get a full extraction of oleoresin. Extracting lycopene oleoresin by subcritical and supercritical propane was then studied with one tomato feed containing less oleoresin. The powder size was kept 30 to 60 mesh. Lycopene content in feed was measured for each run. Data in table 2 show that extraction temperature up to 100% does not cause much lycopene loss. In fact, the recovery rate could reach 90% at higher temperature with more Table 1 Influence of tomato power size and operating conditions on oleoresin yield Figure 4 Oleoresin yield as a function of extraction time by CO2 oleoresin produced.Oleoresin product contains lycopene %. But when thelycopene powder which contain 8wt% water was dried at 105% for 2 hour under vacuum to dry all the moisture out, the recovery rate reduces to only %. When moisture content was reduced to 5% at room temperature under vacuum, no significant reduction in both oleoresin yield a