[Study on the chemical constituents of Pithecellobium clypearia].

OBJECTIVE: To study the chemical constituents of Pithecellobium clypearia. METHODS: Silica gel column chromatography and Sephadex LH-20 were used to separate and purify compounds from the EtOAc soluble fraction of Pithecellobium clypearia. 9 compounds were elucidated on the basis of physicochemical properties and spectrascopic analysis. RESULTS: They were identified as beta-Sitosterol (1), tritriacontane (2), 5-hydroxy-3,7,3',4'-tetramethoxyflavone (3), oleanolic acid (4), 5,4'-dihydroxy-3,7,3'-trimethoxyflavone (5), alpha-amyrin (6), luteolin (7), ursolic acid (8), luteoloside (9). CONCLUSION: Compounds 3 and 5 are isolated from this plant for the first time.

[HPLC fingerprint of Pericarpium Citri Reticultae from Guangdong province].

OBJECTIVE: To establish chromatographic fingerprint of Pericarpium Citri Reticultae from Guangdong province by HPLC and comparison of citrus herbs similarity with different strains and different origin, it was expected to fix standard of quality control. METHODS: 26 samples' analysis was performed on Diamonsil C18 column (250 mm x 4.6 mm, 5 microm) with gradient mobile phase of acetonitrile-1% acetic acid,fingerprint was finished in 65 min, the monitoring wavelength was at 330 nm with the flow rate of 1.0 mL/min. RESULTS: Establishing the fingerprint of Pericarpium Citri Reticultae from Guangdong province, 17 common peaks were found in the HPLC fingerprints from different sources, the similarity of Pericarpium Citri Reticultae from Guangdong province above 0.975 and quite different for different origin drugs. CONCLUSION: This method is simple, accurate with good reproducibility, and can be used specifically for the quality control of Pericarpium Citri Reticultae from Guangdong province.

[Study on the contents of flavonoids in Citrus reticulata 'Chachi' from various habitats and different collecting periods].

OBJECTIVE: To determine the contents of hesperidin, nobiletin and tangeretin in Citrus reticulata 'Chachi' from various habitats and different collecting periods (from October to December) and study the dynamic change of three flavonoids constituents. METHODS: The HPLC method was used for analysis the contents of flavonoids in Citrus reticulata 'Chachi'. The system used a Diamonsil C18 column (250 mm x 4.6 mm, 5 microm) with gradient mobile phase of acetonitrile-methanol (80:20)-2% acetic acid. The monitoring wavelength was at 283 nm and 330 nm and the column temperature was at 25 degrees C with the flow rate of 1.0 ml/min. RESULTS: The contents of hesperidin, nobiletin and tangeretin in Citrus reticulata 'Chachi' collecting from various habitats descended gradually with the mature of fruit, especially in nobiletin and tangeretin. CONCLUSION: The method was simple, convenient and can be used to provide some foundation for the quality control of Citrus reticulata 'Chachi'.