Ting Xia Dong
Hong Kong University of Science and Technology
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Featured researches published by Ting Xia Dong.
Analytica Chimica Acta | 2014
Gui-Zhong Xin; Bin Hu; Zi Qi Shi; Yin Ching Lam; Ting Xia Dong; Ping Li; Zhong-Ping Yao; Karl Wah Keung Tsim
The counterfeit plant products, especially by using incorrect plant materials in pharmaceutical industry, have become a global problem. The plant materials belonging to closely related species but differing in medicinal properties are difficult to be identified. Here, a novel and generally applicable approach to identify the sources of plant materials was developed, which was based on the use of wooden-tip electrospray ionization mass spectrometry (wooden-tip ESI-MS) and multivariate statistical analysis of unidentified MS features (non-targeted). Using this approach, six officinal species of Fritillariae Cirrhosae Bulbus had been successfully differentiated. In addition, Fritillariae Pallidiflorae Bulbus, a common adulterant of Fritillariae Cirrhosae Bulbus, was also identified by using the strategy reported here. Compared with DNA phylogenetic trees, our approach provided finer resolution in distinguishing the closely related Fritillaria species. By combining wooden-tip ESI-MS and multivariate statistical analysis, a useful method was developed here for rapid identification of the sources of herbs, which showed promising perspectives in tracking the supply chain of pharmaceutical suppliers.
Journal of Ethnopharmacology | 2017
Huangquan Lin; Amy G. W. Gong; Huaiyou Wang; Ran Duan; Ting Xia Dong; Kui Jun Zhao; Karl Wah Keung Tsim
BACKGROUND Traditional Chinese medicine (TCM) has contributed greatly to human health in past several thousand years. Today, the development of TCM is facing two obstacles: (i) quality control of herbal extract; and (ii) action mechanisms not known. OBJECTIVES Among thousands of complex TCM formulations, Danggui Buxue Tang (DBT) is the simplest one. DBT is used to treat ailments in women and contains only two herbs, Astragali Radix (Huangqi; AR) and Angelicae Sinensis Radix (Danggui; ASR). The weight ratio of AR to ASR in DBT must be 5:1, as stipulated in AD 1247. By using DBT as a model formula, we develop a strategy to reveal the complexity of a traditional TCM formula. RESULTS There are 3 levels of research directions: (i) the preparation of DBT and its rationale behind; (ii) the traditional theory of DBT is elucidated by chemical and biological determinations; and (iii) the action mechanisms of DBT are revealed. CONCLUSION Through the chemical, biological, genomic and proteomic studies, a possible direction in resolving the preparation mythologies, pharmacological and mechanistic analyses of a TCM decoction is being proposed here.
Molecules | 2015
Shiyu Zong; Han Han; Bing Wang; Ning Li; Ting Xia Dong; Tong Zhang; Karl Wah Keung Tsim
A reliable ultra-high-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (UHPLC–ESI–MS/MS) method for the fast simultaneous determination of 13 nucleosides and nucleobases in Cordyceps sinensis (C. sinensis) with 2-chloroadenosine as internal standard was developed and validated. Samples were ultrasonically extracted in an ice bath thrice, and the optimum analyte separation was performed on an ACQUITY UPLCTM HSS C18 column (100 mm × 2.1 mm, 1.8 μm) with gradient elution. All targeted analytes were separated in 5.5 min. Furthermore, all calibration curves showed good linear regression (r > 0.9970) within the test ranges, and the limits of quantitation and detection of the 13 analytes were less than 150 and 75 ng/mL, respectively. The relative standard deviations (RSDs) of intra- and inter-day precisions were <6.23%. Recoveries of the quantified analytes ranged within 85.3%–117.3%, with RSD < 6.18%. The developed UHPLC–ESI–MS/MS method was successfully applied to determine nucleosides and nucleobases in 11 batches of C. sinensis samples from different regions in China. The range for the total content in the analyzed samples was 1329–2057 µg/g.
Journal of Ethnopharmacology | 2016
Amy G. W. Gong; Kei May Lau; Miranda Li Xu; Huangquan Lin; Ting Xia Dong; Ken Y.Z. Zheng; Kuijun Zhao; Karl Wah Keung Tsim
BACKGROUND Danggui Buxue Tang (DBT), a Chinese herbal decoction containing Astragali Radix (AR; roots of Astragalus memebranaceus (Fisch.) Bunge var. mongholicus (Bunge) Hsiao) and Angelicae Sinensis Radix (ASR; roots of Angelica sinensis Oliv.) at a weight ratio of 5:1, is used to improve menopausal syndromes in women. Several lines of evidence indicate that DBT has strong estrogenic property; however, the action mechanism of this herbal decoction is not known. Calycosin, a major flavonoid in AR, shares similar structure with β-estradiol, and thus which is hypothesized to be the key compound of DBT in responsible for such estrogenic properties. AIMS We aimed to determine the role of calycosin in DBT in terms of its estrogenic functions by the creation of calycosin-depleted DBT (DBTΔcal) and calycosin-added DBT (DBT+cal) herbal extracts. METHODS The signalings triggered by DBT∆cal, DBT+cal, and parental DBT were compared in cultured MCF-7 cells by determining: (i) the activation of estrogen responsive element; (ii) the phosphorylation of estrogen receptor α (ERα); and (iii) the phosphorylation of Erk1/2. The DBT-induced responses were in dose- and/or time-dependent manners. RESULTS The estrogenic signals triggered by DBT were markedly reduced in DBTΔcal, and in contrast the addition of calycosin in DBT, i.e. DBT+cal, enhanced the responses by 2-5 folds; however, calycosin alone did not show such properties. In parallel, the DBT-induced responses could be significantly blocked by inhibitors for estrogen receptor and mitogen activated protein kinases. CONCLUSION Thus, we hypothesize that calycosin is an indispensable chemical in DBT, and which plays a linker in orchestrating multi-components of DBT as to achieve the maximal estrogenic functions. These discoveries should be invaluable in drug development and in investigating the modernization of traditional Chinese medicine from a new perspective.
Molecules | 2017
Qi Zhang; Yiqiong Pu; Bing Wang; Yuqin Wang; Ting Xia Dong; Tao Guo; Tong Zhang; Zhen-Zhen Cai
In this study, we prepared solid dispersions (SDs) of 20(S)-protopanaxadiol (PPD) using a melting-solvent method with different polymers, in order to improve the solubility and dissolution performance of drugs with poor water solubility. The SDs were characterized via differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), and molecular docking and dynamics study. DSC and PXRD results indicated that PPD crystallinity in SDs was significantly reduced, and that the majority of PPD is amorphous. No interaction was observed between PPD and polymers on FTIR and NMR spectra. Molecular docking and dynamic calculations indicated that the PPD molecule localized to the interpolated charged surface, rather than within the amorphous polymer chain network, which might help prevent PPD crystallization, consequently enhancing the PPD dispersion in polymers. An in vitro dissolution study revealed that the SDs considerably improved the PPD dissolution performance in distilled water containing 0.35% Tween-80 (T-80). Furthermore, among three PPD-SDs formulations, Poloxamer188 (F68) was the most effective in improving the PPD solubility and was even superior to the mixed polymers. Therefore, the SD prepared with F68 as a hydrophilic polymer carrier might be a promising strategy for improving solubility and in vitro dissolution performance. F68-based SD, containing PPD with a melting-solvent preparation method, can be used as a promising, nontoxic, quick-release, and effective intermediate for other pharmaceutical formulations, in order to achieve a more effective drug delivery.
Journal of Agricultural and Food Chemistry | 2002
Xia Q. Ma; Q. Shi; Jinao Duan; Ting Xia Dong; Karl Wah Keung Tsim
Journal of Agricultural and Food Chemistry | 2005
Quan Xia; Kuijun Zhao; Zhaogang Huang; Ping Zhang; Ting Xia Dong; Shao-Ping Li; Karl Wah Keung Tsim
Natural Medicines | 2000
Xia Q. Ma; Jinao Duan; Da-Yuan Zhu; Ting Xia Dong; Karl Wah Keung Tsim
China journal of Chinese materia medica | 2007
Xiaobing Dong; Jun Li; Yong Jiang; Zheng Y; Ting Xia Dong; Peng-Fei Tu; Tsim Wk
Asian Journal of Traditional Medicines 2010 | 2010
Jun Li; Wing Han Cheung; Wenchuan Bi; Ran Duan; Ken Y.Z. Zheng; Wen Huang; Ji J. Chen; Ting Xia Dong; Karl Wah Keung Tsim