| Pogostemon cablin Benth (Labiatae) is a common used Traditional Chinese Medicinal herb. It is used to remove dampness, relieve summer-heat, stop vomiting and stimulate the appetite. Its essential oil shows significant antifungal and antibacterial activities. Presently, most attentions are paid to its essential oil from this plant. For the purpose of making full use of the medicinal herb, several parts from P. cablin are studied.PTRIs are first used to assist GC-TOF MS identification of P. cablin Benth essential oil, which helps GC-MS to distinguish isomeric compounds. Seven compounds including pinene, limonene and patchoulene et al are identified more reliablely.Homologue separation methods (HPLC, Silica gel CC) are first used to pretreat the essential oil, and 21 other compounds are identified with homologue separation methods. Eleven compounds not reported before are tentatively determined, including p-propenylanisole, dibutyl phthalate, a-naphthylphenylamine, butylated hydroxytoluene, 2,5-dimethyl-3,4-hexanediol, diphenylsulfide, and five saturated linear hydrocarbons.The 95% ethanol extract is processed by means of solvent partition macroporous adsorption resin, silica gel column. Three compounds are obtained from chloroform extract, and their structures are elucidated on the basis of the data of IR, MS, 1D NMR, 2D NMR and physical properties. These compounds are 5-hydroxy-7, 3', 4' -trimethoxy fiavanone, 5-hydroxy-3, 7, 3', 4'-tetramethoxyflavone, 5, 4'-dihydroxy-3, 7, 3'-trimethoxyflavone.The content of total flavonoids from P. cablin is valued to be 11.61 mg·g-1 by means of spectrophotometry, through comparison of ultrasonic method and refluxing method, both methods extract most of the flavonoids in 1 h, and the contents of total flavonoids reach highest in 6～8 h, but the extract efficiency of ultrasonic method is a bit higher than refluxing method. AB-8 and D101 types of macroporous resin are applied to extract and purify flavonoids, and the result shows that the adsorption capacity of D101 and AB-8 resin are 0.6649 mg·g-1and 0.3560 mg·g-1, respectively. The desorptional capacities of D101 and AB-8 are73.92% and 82.11%, respectively, when 95% alcohol is used to elute the flavonoids. |
