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Objective: To investigate the chemical constituents of the lichen plants Parmelia tinctorum and Parmelia nimandairana collected from Meng Mountain in Shandong province., Methods: Various chromatographic techniques were used to isolate and purify the constituents and their structures were elucidated by means of spectral evidence and physiochemical properties., Results: Four compounds were isolated from Parmelia tinctorum and identified as: lecanoric acid (I), evernic acid (II), ethyl orsellinate (III) and 3,5-dihydroxytoluene (IV). Two compounds were isolated from Parmelia nimandairana and identified as: usnic acid (V) and salazinic acid (VI)., Conclusion: Compounds V and VI are isolated from Parmelia nimandairana for the first time.

Objective: To study the chemical constituents in ethyl acetate fraction from the Euphorbia fischeriana., Methods: The compounds were isolated by silica gel column chromatography and HPLC, and their structures were elucidated by means of spectral analyses., Results: Fourteen compounds were identified as 2,4-dihydroxy-6-methoxy-3-methylacetophenone (1), 12-deoxyphorbol-13-hexadecanoate (2), ethylgallate (3), esculetin (4), 2,4-dihydroxy-6-methoxy-acetophenone (5), 12-deoxyphorbol-13-acetate (6), 12-deoxyphorbol-13,20-diacetete (7), jolkinolide B (8), 17-hydroxyjolkinolide B (9), 17-hydroxy-jolkinolide A (10), langduin C (11), 3-methylp-hydroxybenzoic acid (12), methyl gallate (13), 3, 3'-diacetyl-pyridine-4,4'-dimethoxy-2, 2', 6, 6'-tetrahydroxydiphenylmethane (14)., Conclusion: Compounds 3, 5, 12, 13 are isolated from this plant for the first time.

The latest progress in research on constituents and pharmacological activities of sarcotestas of Ginkgo biloba has been studied. The main constituents in sarcotestas of G. biloba include flavones, ginkgolides, alkylphenols, polysaccharides and amino acids, etc. They show the following activities, such as bacteriostatic, bactericidal and pesticidal activities, antitumor and mutagenic, carcinogenic effects, antianaphylaxis and allergenic activity, effects on immunologic function, scavenging free radical, antisenile action, etc. The problems at present and the reseach direction for the future on sarcotestas of G. biloba have been put forward.

Objective: To isolate ginkgolic acids (GA) from exopleura of Ginkgo biloba and to analyse GA., Methods: GA were ultrasonic-extracted from exopleura of Ginkgo biloba with petroleum ether, and purified by silica gel column chromatography. The content of GA in sample was determined by HPLC with methanol-3% acetic acid (90:10) as mobile phase at a flow rate of 1 ml/min. UV detection wavelength was set at 310 nm. A HiQ sil C18 column was used at 40 degrees C in analysis., Results: A good linearity was obtained in the range of 1.144-5.720 micrograms (r = 0.9978) for GA. The average recovery of GA was 97.50% with RSD of 1.70%., Conclusion: The method may be employed to prepare GA from exopleura of Ginkgo biloba. The analysis method for GA is accurate and reliable, and can be used for determination of GA in sample.

The technology of supercritical CO2 fluid extraction for ginkgolic acids in the epicarp of Ginkgo biloba L. was studied. The effect of pressure, temperature and extraction time on the yield of the ginkgolic acids was explored. The optimum conditions for supercritical CO2 fluid extraction was 30 MPa, 45 degrees C, extraction time 6 h and the flow rate of CO2 2L/min. The ginkgolic acids were determined by HPLC. Supercritical CO2 fluid extraction exceled the traditional solvent extraction in high yield, high purification and easy operation.

Aim: To develop a method for separating salicylic acid drugs by aqueous and nonaqueous capillary electrophoresis with conductance detector., Methods: Fused-silica capillary (55 cm x 50 microns ID) was used. The effects of concentration and pH of the running buffer, running voltage and injection time were studied. Salicylic acid (SA), acetylsalicylic acid (ASA) and sulfosalicylic acid (SSA) can be separated in a 10 mmol.L-1 Tris-30 mmol.L-1 H3BO3 buffer (pH 8.0), the separation voltage and injection time were 24 kV and 10 s, respectively. But tailing peaks appeared. In order to improve the separation efficiency and the sensitivity, ethanol was used as nonaqueous solvent., Results: High sensitivity and resolution for SA, ASA and SSA were obtained in ethanol media, and there was excellent linearity between peak area and concentration of the analytes in the concentration range of 0.05-100 mg.L-1, 5.0-250 mg.L-1 and 0.08-100 mg.L-1 for SA, ASA and SSA, respectively. All the correlation coefficients were over 0.995., Conclusion: The analysis of SA and ASA in aspirin tablets was tried and good results were obtained in ethanol media. There was higher sensitivity and separation efficiency than in aqueous media.

In this article we studied the anti-bacterial activity of the extract from testa of Ginkgo biloba and ginkgolic acids. They can inhibit the growth of Staphylocococus aureus, Escherichia coli, Bacillus subtilis, B. cereus and MRSA. Ginkgolic acids combined with peniciline can enhance their inhibitory activity to MRSA.

Objective: To study the chemical constituents from the fruit bodies of Umbilicaria esculenta., Method: Five compounds were isolated from the ethanolic extract of this plant by all kinds of column chormatography, and structures were identified by spectroscopic analysis., Result: Five compounds were identified as ethyl orsellinate, orsellinic acid, orcinol, lecanoric acid and lecanorin., Conclusion: Ethyl orsellinate, orsellinic acid, orcinol and lecanorin were isolated from this plant for the first time.

Aim: To develop a reverse phase argentation high performance liquid chromatographic (RP-AHPLC) method for the separation and determination of ginkgolic acids., Methods: Liquid chromatography-electrospray ionization mass spectrometry (LC/ESI-MS) was applied to identify ginkgolic acids from Ginkgo biloba leaves and four ginkgolic acids of the samples were separated and quantified by RP-AHPLC. Leaves were extracted with ethanol and analytes were extracted with hexane after addition of acid/salt solution and adsorbent to matrix solution. Ginkgolic acids were separated and determined within 30 minutes by RP-AHPLC under optimum chromatographic conditions. Methanol and 5% aqueous acetic acid (90:10) containing 0.03 mol.L-1 silver ion was used as mobile phase, column temperature was selected at 30 degrees C, flow rate was 1.0 mL.min-1, UV detection wavelength was at 310 nm. The spectra analysis and purity identification of chromatographic peaks of ginkgolic acids were further confirmed by means of diode array detection., Results: Four ginkgolic acids were baseline separated from each other and from other interfering components. The average recovery and relative standard deviation of the method were 97.3% and 1.6%, respectively., Conclusion: RP-AHPLC was an excellent method for separation of homologous with different carbon atom numbers and double bond. The method is useful for the quality control of extract of Ginkgo biloba leaves.