| Bamboo shoots are the tender young growth of bamboo, which is a kind of primary agricultural products in China. The annual output of bamboo shoot is above 2, 170, 000 ton now and the majority is canned and dried. However, the simplified processing style and much more competitive market had resulted in poor economic benefit for all of processing enterprise. Furthermore, shoot shell, shoot liquid waste and shoot root are generated largely as staple waste during the course of water-boiling-shoot caning process, which have resulted in serious environmental pollution.For effective, economic and comprehensive utilization of the resources of bamboo shoots, the present works were located on its secondary metabolites with healthy benefits, especially to research the chemistry component, separation technology and functionality of the phytosterol component in bamboo shoot thoroughly. The main results were as follows:(1) The secondary metabolites in various species of bamboo shoot were scanned and analyzed. The most abundant component was phytosterols (251.4-279.5 mg/100g dry.wt) and the predominant compound isβ-sitosterol, as well as campesterol, stigmasterol, ergosterol, cholesterol and stigmastanol. The differences of species, parts and harvest seasons could affect the total sterol content. Among of all tested samples, the shell of spring shoot of Phyllostachys pubescens was of the highest level of total sterols. It could be concluded that bamboo shoot is a sterol-rich healthy food and its processing garbage, shoot shell and shoot root, is a potential resources of phytosterols.(2) The Liebermann-Burchard colorimetric method has been improved to quantify the content of total sterols in bamboo shoots and extracts. The time of chromogenic reaction was adjusted to 12mins and the wavelength for recorded absorb value was changed to 665nm. This revised method is much suitable for on-line detection in factory. An ultra-performanceTM liquid chromatographic-mass spectrometer method(UPLC-APCI-MS) for the analysis of sterol compounds in food and raw material has been established at first time. The procedure is as below: bamboo sample was extracted using by supercritical carbon dioxide fluid and the extract was saponified by ethanol KOH. Then the non-saponificable fraction was extracted with petroleum ether, purified by solid phase extraction on silica gel cartridge, separated on an Acquity UPLCTM BEH C18 column with a gradient of methanol/water(1％acetonitrile). At last, the determination was performed under selected ion monitoring mode using 6-ketocholestanol as internal standard. This method is much more sensitive, selective, speedy and reliable approach for the determination and quantification of sterol compounds.(3) Results of technologic research showed that SCE was of higher extract efficiency and total sterol yield than traditional hexane extraction method. A contrast experiments, central composite rotate design and response surface methodology have been used to obtain optimum experimental parameters in supercritical CO2 fluid extraction(SCE): granularity of raw materiel 40-60 mesh, not additive solvent used, extraction pressure 26.2MPa, extraction temperature 43.4℃, CO2 flow rate 25.4L/h, extraction time 2.5h. Under this optimum technology condition, the theoretic maximum extracting yield of bamboo shoot sterol was 98.4％. A serial of amplification tests of SCE(available extracting volume at 5L, 24L and 300L respectively) has proved that above technology condition was of good adaptability. The preparation of phytosterol of bamboo shoot made by SCE is defined as PBS25, and its total sterol content is above 250mg/g.(4) Using the short path molecular distillation(MD) technology, PBS25 was purified into PBS50that contains total sterols at above 50％. The contrast experiments, central composite rotate design and the response surface methodology have been conducted for obtaining the optimum experimental parameters of MD. Taking the yield of final product as index, the optimum technologic parameters were pressure at 0.013mbar and distillation temperature at 180℃; taking the total sterol content of final product as index, the optimum technologic parameters were pressure at 0.005mbar and distillation temperature at 220℃. During with MD purification, most of alkane and fatty acid in PBS25 was take off, and the total sterol content in final product(PBS50</sub> was increased significantly.(5) The effects of PBS on lipoprotein metabolism were evaluated using by hypercholesterolemia rats model. Result showed that, PBS could significantly lower the cholesterol levels of rats, include TC, TG, LDL-c as well as AI, but no effect on HDL-c, and PBS could effectively protect rat liver tissue. It has also been proved that PBS25 has better impact on lowering-cholesterol and much lower producing cost than PBS50. Thus, PBS25 could be regarded as the best bioactive part of bamboo shoot for lowering cholesterol. Its bioactivity of adjusting lipid metabolism should be related with both phytosterols and poly-unsaturated fatty acid. The potential mechanism of lowering-cholesterol is related with inhibiting absorbability and accelerating drainage of extrinsic lipid, and inhibiting synthesis and increasing metabolism of intrinsic lipid and triglyceride.(6) An excellent anti-inflammatory property of PBS25 was proved in three different animal models. PBS25 exhibited strong anti-inflammatory effect, shown as inhibition of croton oil-induced ear oedema in mice, inhibition of egg white-induced hind paw swelling in rats and inhibition of acetic acid induced vascular permeability in mice. Xiaozhiling induced experimental chronic nonbacterial prostatitis model was used to evaluate the effect of PBS25 on prostatitis. Result showed that, PBS25 could inhibit significantly prostate swelling and inflammatory, protect acinar epithelial cells, inhibit stromal proliferation and recover excretion function of prostate. Principal mechanism of PBS25 on treating chronic prostatitis is related with that, (1)antioxidant properties of PBS25; (2) PBS25 was capable of stabilizing membrane stabilization; (3) PBS25 could modulate expression of inflammatory cytokines and receptors in chronic nonbacterial prostatitis.
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