Qualitative and quantitative analysis of chemical constituents in Ardisiae Japonicae Herba.

Ardisiae Japonicae Herba is a well-known traditional Chinese medicine for the treatment of bronchitis conjunctivitis, pneumonia, and trauma. In this work, a high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry method was first established for the separation and structural identification of the chemical constituents in Ardisiae Japonicae Herba. A total of 15 compounds including coumarins, flavonoid glycosides, and catechins were identified or tentatively characterized based on their chromatographic behaviors and mass spectral fragmentation and by comparisons with the reference standards. Furthermore, a simple high-performance liquid chromatography with diode array detection method was developed for the simultaneous determination of five major constituents. Results obtained from method validation, including linearity, precision, repeatability, stability, and recovery, showed that the established method was reliable and accurate. Bergenin and quercitrin were found to be the most abundant constituents and could be served as chemical markers for quality control of Ardisiae Japonicae Herba.

Polymethoxyflavones in peel of Citrus reticulata 'Chachi' and their biological activities.

Citrus polymethoxyflavones (PMFs) have been of increasing interest due to their extensive biological activities. In the present study, a total of eight PMFs were isolated from the peel of Citrus reticulata 'Chachi' (CRC). They were individually identified as 5-hydroxy-6,7,8,4'-tetramethoxyflavone (1), 5,6,7,3',4'-pentamethoxyflavanone (2), 5-hydroxy-6,7,8,3',4'-pentamethoxyflavone (3), 3,5,6,7,8,3',4'- heptamethoxyflavone (4), 5,6,7,8,3',4'-hexamethoxyflavone (5), 5,6,7,8,4'-pentamethoxyflavone (6), 6,7,8,3',4'-pentamethoxyflavanone (7) and 5,6,7,3',4'-pentamethoxyflavone (8) by nuclear magnetic resonance and mass spectroscopic analysis. 6,7,8,3',4'-Pentamethoxyflavanone was isolated from the peel of CRC for the first time. The content of PMFs was firstly quantified in both the peel of CRC and PMF-rich extract by HPLC analysis. Furthermore, the biological activities of PMF compounds were investigated. 3,5,6,7,8,3',4'-Heptamethoxyflavone demonstrated potent sterol regulatory element-binding proteins inhibition activity and 5-hydroxy-6,7,8,3',4'-pentamethoxyflavone exhibited strong antiproliferative activity against tumor cell lines. The isolated PMF compounds could also significantly inhibit NO production and the effect varied mainly depending on the number of methoxy groups.

A new compound, methylbergenin along with eight known compounds with cytotoxicity and anti-inflammatory activity from Ardisia japonica.

A new compound, methylbergenin (1), was isolated from the whole plants of Ardisia japonica (Thunb.) Bl. (Myrsinaceae), along with eight known compounds: demethoxybergenin (2), bergenin (3), afzelin (4), quercitrin (5), bauerenol (6), bauerenone (7), α-spinasterol (8) and chondrillasterone (9). Compounds 1, 7 and 9 were isolated from A. japonica for the first time. The structure of compound 1 was determined on the basis of NMR (1D and 2D) and mass spectroscopic analysis. The absolute configuration of 1 was assessed by single-crystal X-ray diffraction. Compounds 1, 4, 5, 7 and 9 showed potential inhibitory effects against nitric oxide production in LPS stimulated RAW 264.7 murine macrophages. In addition, Compounds 7 and 9 exhibited cytotoxicity against A549 and HepG-2 cells.

Comparison of chemical profiling and antioxidant activities of fruits, leaves, branches, and flowers of Citrus grandis 'Tomentosa'.

Citrus grandis 'Tomentosa' (CGT) is particularly cultivated in China and widely used in health foods. In this study, the chemical profiles of different parts of CGT were comprehensively compared by rapid resolution liquid chromatography coupled to electrospray ionization quadrupole time-of-flight mass spectrometry method. A total of 22 compounds were identified and two C-glucosyl flavones were found for the first time in CGT. Four main constituents (rhiofolin, naringin, meranzin hydrate, and isoimperatorin) in different parts of CGT were simultaneously determined. Overall, the contents of the four main compounds decreased with the ripening process. In parallel, the antioxidant activities of their extracts were also evaluated by three assays (2,2'-azinobis(3-ethylbenzthiazolinesulfonic acid) diammonium salt, 2,2-diphenyl-1-picrylhydrazyl, ferric reducing antioxidant power), and the results indicated a similar tendency: small fruit > flower ∼ medium fruit > large fruit > leaf ∼ branch. The results obtained in the present work may provide useful information for future utilization of CGT.