Chinese material medica is the natural therapeutic agent used under the guidance of the theories of traditional Chinese medicine.Its sources are mainly derived from plants,some derived from animals and minerals,and a few derived from chemical drugs and biologic products.It was made up into a colossal complex system because of its diversity of biological sources,ecological environments, chemical constituent structures,processing methods,processes of metabolism-disposition and their products in intra-body,biological activity and clinical use,and involved a lot of scientific problems.The elucidation of the toxic-invited constituents and toxic-effective substances is one of basic and scientific problem to clarify complex system of Chinese material medica.Along with the research progress of processes of metabolism and disposition of Chinese material medica in intra-body and metabonomics,a new and rapid-developing technology,the discovery strategy for toxic-invited constituents and toxic-effective substances on Chinese material medica based on the processes of metabolism and disposition would be made up,which will provide a new methodology and pathway to clarify of complex system of Chinese material medica.

The problem on study of the active and toxic constituents of Chinese materia medica is the core of the problems in the field of modern research of Chinese materia medica. But approved methods for ascertaining the active and toxic constituents in Chinese materia medica have not been developed yet and are in developing phases. In combination with the characteristics of Chinese materia medica in clinical use and the achievements of modern pharmaceutical research, series model may be a finer approach to make certain of the active and toxic constituents from Chinese materia medica, which includes the parent compound biotransformation by human intestinal bacteria to make biotransformation products, and the absorption and further biotransformation in intestinal wall, the metabolization in the liver, and the secretion by the kidney of the parent compounds and biotransformation products. This method is also an important research assignment in the field of experimental medicine study of Chinese materia medica.

The word of named "Chinese herbal medicine"(CHM)is a compound word or an expression which has included the combined meaning of traditional Chinese medicinal materials(TCMM)and herbal medicine(HM).The contained entitative means for TCMM and HM are far different in medicinal use,though they are both the origin from plants,animals,some minerals,and a few artificial biomaterials or biomimetic materials.TCMM has been used under the guidance of the traditional Chinese medicine(TCM)theories and has its firm clinical foundation,significant therapeutic effect,and unique system of theory based on the clinical practice.Although the western modern medicine has developed promptly and superseded the national and folk medicines gradually among most countries,TCMM still stands steadily and is bursting with great vitality in the pharmaceutical field all over the world.Nowadays,it is developing more rapidly than at any other times in the past.Therefore,it is in the full conviction that the substantial basis and active chemical constituents or components are present in CHM used for the prevention,cure,and healing of various diseases.It is this conviction that leads us to study the chemical constituents or components exhaustively in order to deeply reveal them by a variety of assessment methods and ways which possess the merits and demerits during the tentative use for a long time.So it is very important to systematically summarize and develop these methods and ways for further research of the chemical cons-tituents and sustained utilization of the biological resources of CHM.

From the soon-to-be-completed Human Genome Project to Combinatorial Chemistry and High-Throughput Screening combined with bioinformatic tools, scie n tific advances are poised to revolutionize drug discovery and even health care. The research directions in the State Key Laboratory of Natural and Biomimetic Dr ugs of Peking University mainly focus on the study of interaction between biolog ical targets and active compounds with structural diversity including endogeno us and exogenous substances, especially the natural products that come from anim als, plants and inorganic medicines. The new lead compounds have been designed and s ynthesized based on the structure-activity relationship and computer modeling. T he research activities are involved in 76 national research projects. From 1996 -20 00, 310 papers have been published, 8 patents obtained an d 14 prizes of scientific achievements awarded by the Chinese government and min istries.

Aim To investigate the pharmacokinetics of nodakenin(ND),one of main chemical constituents in the rhizome and root of Notopterygium incisum Ting ex H.T.Chang and N.forbesii Boiss.,in rats.Methods SD rats were used throughout the experiment and their body weights ranged from 200 to 220 g.All of them were distributed randomly to different test groups(5 rats per group).Nodakenin was administered at a single dose of 80 mg?kg-1 via tail vein.The blood was collected from the orbital venous plexus at different time points.A reversed-phase high performance liquid chromatography(RP-HPLC) method,in which the analyte was isocratically eluted and the external standard method was used,was developed to determine concentrations of ND in rats.The main parameters of pharmacokinetics were calculated by 3P87 software.Results Under the established conditions of HPLC,the retention time of ND was 6.7 min.The calibration curve was Y=2.0?10-4 X+0.4(r=0.9999) with a validated quantitation range from 0.2 mg?L-1 to 80 mg?L-1.The lower limits of detection(LLOD) and quantification(LLOQ) in rats plasma were 0.01 mg?L-1(S/N=3) and 0.1 mg?L-1(S/N=10),respectively.At the concentrations of 1.0,10.0 and 40.0 mg?L-1,extraction recoveries were ranged from 76.23% to 83.72%.The RSD of the precision intra-and inter-day were less than 5.60%(n=3).ND was stable at room temperature and freeze-thaw cycles.The concentration-time course of ND was best fitted to a two-compartment open model after a single intravenous injection dose of 80 mg?kg-1,which the main pharmacokinetic parameters t1/2?,t1/2?,AUC,Vc,Vp,Vss,CL were 7.02 min,219.27 min,1384.34 mg?min?L-1,0.92 L?kg-1,6.04 L?kg-1,6.96 L?kg-1,0.06 L?kg-1?min-1,respectively.Conclusion The developed method is shown to be rapid,accurate and simple,and can satisfy the requirement of pharmacokinetic study of ND in rat.ND was distributed widely and eliminated moderately after a single intravenous injection dose of 80 mg?kg-1 in rats.

OBJECTIVE: To study the absorption and transport of pachymic acid (PA) isolated from the sclerotium of Poria cocos (Schw.) Wolf. in human intestinal epithelium. METHODS: By using Caco-2 (the human colonic adenocarcinoma cell lines) cell monolayers as an intestinal epithelial cell model, the permeability of PA was studied from apical side (AP side) to basolateral side (BL side) or from BL side to AP side. The PA was measured by reversed-phase high performance liquid chromatography coupled with UV detector at maximum absorption wavelength of 210 nm. Transport parameters and apparent permeability coefficients (Papp) were then calculated and compared with those of propranolol and atenolol, which were the transcellular transport markers for high and poor permeability respectively. RESULTS: The Papp values of PA were (9.50+/-2.20) 10(-7) cm/s from AP side to BL side, and (11.30+/-5.90) 10(-7) cm/s from BL side to AP side, respectively. Under the condition of this experiment, the Papp values were 1.45x10(-5) cm/s for propranolol and 4.22x10(-7)cm/s for atenolol. CONCLUSION: PA is transported through the Caco-2 cell monolayer in a concentration-dependent manner and the transport was linear with time. The absorption in apical to basolateral direction and secretion in basolateral to apical direction were poor and their Papp values were comparable to atenolol. Besides passive diffusion of PA, ATP is partially involved in its transport.

Objective To carry out a systematic study on the chemical constituents in the fruits of Momordica grosvenori. Methods To isolate pure compounds by using repeated column chromatography,while the structure of a new compound was determined by detailed spectral analysis. Results Four cucurbitane triterpenoid glycosides, mogroside Ⅱ E (Ⅰ), mogroside Ⅲ (Ⅱ), grosmomoside Ⅰ (Ⅲ), and mogroside Ⅴ (Ⅳ) were isolated from the 50% ethanolic extract of the fruits of M. grosvenori. Conclusion Grosmomoside Ⅰ is a new compound identified as mogrol-3-O-β-D-glucopyranoside-24-O-{[β-D-glucopyranosyl (2-1 ) ]- [β-D-glucopyranosyl (6-1 ) ]-β-D-galactopyranoside } and the other three compounds are known compounds.

A new flavonoid glucoside was isolated from the aerial parts of Alhagi pseudoalhaki (M. B. )Desv.. Onthe basis of spectral data and chemical reaction,it was elucidated to be syringetin-3-O-?-D-glucoside- Moreover,fourteen known compounds have been isolated and identified as Psitosterol, stigmasterol,kaempferol,rhamnetin, ombuine, isorhamnetin, tamarixetin, kaempferol-3-O-?-D-(6″-O-p-coumaroyl )-glucoside, isoquercitrin, D-3-O-methylinositol, 1-O-?-D-methyl-glucoside, isoswertianolin, isorhamnetin-3-O-?-D-rutinoside,and tyramine. These compounds were isolated for the first time from the aerial parts of A. pseudoalhagl.

Objective To study the chemical constituents in the fruits of Momordica grosvenori. Methods Isolation and purification of the constituents were carried out on column chromatography. Their structures were identified by NMR and MS spectral analyses. Results Ten compounds were isolated and elucidated as kaempferol (Ⅰ), kaempferol 7-O-?-L-rhamnopyranoside (Ⅱ), kaempferitrin (Ⅲ), mogroside ⅡE (Ⅳ), mogroside Ⅲ (Ⅴ), kaempferol 3-O-?-L-rhamnopyranoside-7-O-[?-D-glucopyranosyl (1-2)-?-L-rhamnopyranoside] (Ⅵ), mogroside ⅣA (Ⅶ), grosmomoside Ⅰ (Ⅷ), mogroside Ⅴ (Ⅸ), and mogroside ⅡA1 (Ⅹ). Conclusion Compounds Ⅶ and Ⅹ are new natural products, and Ⅰ is isolated from the fruits of M. grosvenori for the first time.

Objective To study the constituents from the berry of Panax ginseng. Methods Compounds were separated and purified by column chromatographic methods. Their structures were elucidated by physicochemical properties and spectral analyses. Results Twelve compounds were isolated from water extracts of the berry of P. ginseng. They were identified as benzoic acid (Ⅰ), isoginsenoside-Rh3 (Ⅱ), ginsenoside-Rh2 (Ⅲ), ginsenoside-Rh1 (Ⅳ), ginsenoside-Rg1 (Ⅴ), ginsenoside-Re (Ⅵ), ginsenoside-Rd (Ⅶ), ginsenoside-Rc (Ⅷ), ginsenoside-Rb2 (Ⅸ), ginsenoside-Rb1 (Ⅹ), ?-sitosterol (Ⅺ), and 20-O-?-D-glucopyranosyl-20 (S)-protopanaxadiol named as compound K (ⅩⅡ). Conclusion The compound K is a new natural product.