| The heartwood of Dalbergia odorifera T. Chen. (Leguminosae) is a traditional Chinese medicine, named as Jiangxiang in Pharmacopoeia of PRC. The chemical constituents of D. odorifera and its quality control method, as well as the metabolism of this medicinal herb were investigated in detail.The chemical constituents of D. odorifera were systematically studied and 27 compounds were purified by silica gel, sephadex LH-20 and ODS column chromatography. Utilizing chemical and spectroscopic methods (UV, IR, NMR, MS), the structures of 25 compounds were fully characterized, including 24 flavonoids and 1 oleanolic acid. Ten of these constituents were isolated from D. odorifera for the first time.The method of HPLC-fingerprint analysis was established for the quality control of D. odorifera. The 37 batches of D. odorifera samples were analyzed and classified into three types based on the results of similarity analysis. Furthermore, the typical samples were detected by LC/ESI-MS under the negative ion mode, and the main constituents of D. odorifera were identified. The method is repeatable and reliable, and proved to be able to effectively control the quality of D. odorifera.The major flavonoids in D. odorifera were analyzed qualitatively and quantitatively by high performance liquid chromatography and its coupling to mass Spectrometry. A HPLC-DAD/ESI-MS~2 method was developed for the qualitative characterization of flavonoids in D. odorifera. Twenty-three flavonoids including six isoflavones, six neoflavones, four isoflavanones, three flavanones, two chalcones, one isoflavanonol and one pterocarpan were unambiguously identified by comparing their retention times, UV and MS spectra with those of authentic compounds. Furthermore, the MS/MS spectra were studied by collision-induced dissociation (CID) from the [M-H]~- ions to clarify the mass spectrometric behavior of different types of flavonoids. HPLC-UV methods were developed for the simultaneous quantification of major flavonoids in D. odorifera: ten constituents were detected at 275 nm and nine were detected at 350 nm. The current assay methods were applied to 32 batches of samples and considered to be suitable for the quality control of Dalbergia odorifera samples.The absorption, distribution, metabolism and extraction of flavonoids in rat after oral administration of D. odorifera extract were preliminarily investigated. The major flavonoids in rat serum, urine and tissues were analyzed qualitatively and quantitatively by high performance liquid chromatography and its coupling to mass spectrometry. Utilizing HPLC-MS technique, eighteen flavonoids including five isoflavones, four isoflavanones, four neoflavones, two flavanones, two chalcones, one isoflavanonol were detected in free form in serum and urine samples based on comparison with the authentic standards. Moreover, 16, 17, 7, 10 and 7 flavonoids were identified in free form in liver, kidney, lung, heart and spleen samples, respectively. Furthermore, the amounts of the four prominent flavonoids, (3R)-4'-methoxy-2',3,7-trihydroxyisoflavanone, vestitone, formononetin and sativanone were determined in serum and tissues by HPLC-UV with internal standard method; (3R)-4'-methoxy-2',3,7-trihydroxyisoflavanone and vestitone were determined in urine. The methods were validated and utilized in pharrnacokinetic studies, distribution in tissues and renal excretion of these analytes. The sulfate and glucuronide conjugates of the flavonoids in rat were studied by hydrolysis withβ-glucuronidase/sulfatase. Most of the flavonoids could be detected both before and after enzyme treatment, which suggested that the flavonoids were present in both free and conjugated forms in rat. Further studies showed that sulfation was the primary conjugation in rat, while glucuronidation was not remarkable. The investigation on the metabolism of D. odorifera extract provided a firm basis for clarifying the pharmacological effect of D. odorifera and evaluating the clinical applications of this medicinal herb.Under the direction of theory and clinical practice of TCM, utilizing the knowledge of phytochemistry, pharmaceutical analysis, pharmacognosy, pharmacology and pharmacokinetics, the quality assessment methods for D. odorifera were developed, the metabolism of this medicinal herb was also investigated to some extend. This research provided a beneficial exploration for the modernization of traditional Chinese medicine.
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