•For the first time, the chemical characteristics of the procyanidins in Spatholobus suberectus (SS) were clearly described, including the mean degree of polymerization (mDP), the elementary units, the mass distribution of fractions with different mDP values, and the types of linkages. The SS procyanidins have unique chemical profiles and are beneficial sources of antioxidants and potential inhibitors of LDH-A and breast cancer.•Procyanidins with mDP values of 2–6 were likely to be the substances responsible for its bioactivity.•The graded precipitations method was applied effectively to separate the SS procyanidins with different mDP values.Spatholobus suberectus (SS) is an excellent functional and medicinal food source of dietary procyanidins, which have numerous health benefits. Ten procyanidin fractions with different polymerization degrees were prepared from SS. For the first time, trimers to 11-mers were detected in SS extracts, and their compositions were elucidated through thiolysis, ESI-MS and MALDI-TOF-MS analyses. The results determined that the mean polymerization degree (mDP) of the crude SS procyanidins was 5.2 and that the mass distribution of the monomer and the oligomers (mDP of 1.0–5.7) was 70.4%, whereas that of the polymers (mDP of 6.2–11.8) was 25.6%. Catechin and epicatechin were the main monomeric units with minor quantities of epigallocatechin and gallocatechin. The observed interflavan linkages were both A-type (minor type) and B-type (major type). The fractions enriched in the monomer and oligomers showed the highest activities, including antioxidant activity and inhibitory activities on both the proliferation of MCF-7 breast cancer cells and lactate dehydrogenase A (LDH-A). These results suggested that the monomer- and oligomer-enriched procyanidin fractions from SS could undergo further development to become a beneficial source of antioxidants, LDH-A inhibitors, and potential inhibitors of breast cancer.

Using the HPLC-DAD-ESI-MS/MS method, polyphenols and purine alkaloids were analyzed in young leaves of 22 tea cultivars mainly for making oolong tea in China. Ultrasonic extraction in acetonitrile–water (1:1, v/v) was chosen for the preparation of samples for HPLC analysis. Separations were performed on an ODS column with linear gradient elution by the mobile phase consisting of acetonitrile and 1% formic acid aqueous solution. Compared with the standards and data in the literature, 11 catechins, two purine alkaloids, and three non-catechin type of polyphenols were identified, including (−)-epigallocatechin-3-(3″-O-methyl) gallate, (−)-epigallocatechin-3,5-digallate, (−)-epicatechin-3-(3″-O-methyl) gallate, and (−)-epicatechin-3,5-digallate, which are not common catechins in all tea leaves. The contents of the major components, nine catechins and two purine alkaloids were quantified by the HPLC method which were fully validated. The composition of catechins in the leaves of Fujian and Taiwan cultivars group was similar, while the contents of gallated catechins were higher in Guangdong cultivars group than in Fujian and Taiwan cultivars group.

The liquid chromatography–electrospray ionization-tandem multi-stage mass spectrometry (LC–ESI-MSn) method was developed for the analyses and characterization of steroidal saponins in plant extract from the rhizome of Dioscorea nipponica Makino. The HPLC experiments were performed by means of a reversed-phase C18 column and a binary mobile phase system consisting of water and acetonitrile under gradient elution conditions. Pseudoprotodioscin, methyl protodioscin and dioscin were identified by comparing the retention times, UV spectra and the fragmentation properties of [M − H]− ions with the authentic standards. Four groups of steroidal saponin isomers possessed the [M − H]− ions at m/z 1063, 1045, 901 and 1047, respectively, were observed during the LC–ESI(−)-MS analysis, and three groups of them except the pair of isomers with the [M − H]− ions at m/z 1047 could be differentiated by LC–ESI(−)-MS3. Furthermore, the ESI-MSn fragmentation behaviors of the [M + Li]+ ions of pseudoprotodioscin and methyl protodioscin have been investigated, and the observed information helped the structural elucidation of the more abundant isomer with the [M − H]− ion at m/z 1047. As the result, a special sugar sequence of the saccharide chains was observed that not glucose but rhamnose might be connected with the hydroxyl group at C-3 position of the steroidal aglycone.

ObjectiveBao-Xie-Ning (BXN), a traditional Chinese herbal medicine (CHM) formula composed of Fructus Evodiae, Flos Caryophylli and Cortex Cinnamomi, and used for the treatment of infant diarrheal illness, was subject to systematic assessment for its putative multiple pharmacodynamic effects and pharmacological antidiarrheal mechanisms.MethodsHigh-performance liquid chromatography-diode array detector-electrospray ionizationmass spectrometric/mass spectrometry was developed and validated for identification and quantification of the main constituents in different extracts of BXN. Male Kunming mice weighing 20 to 25 g were used for detecting the antidiarrheal activity of the extracts. Ethanolic extract (EE), volatile oil extract (VOE), and aqueous extract (AE) of BXN were respectively subjected to pharmacodynamic and pharmacological comparison in assessing antidiarrheal effects with senna-induced diarrhea, castor oil-induced diarrhea, acetic acid-induced writhing assay, and isolated duodenum test.ResultsThe highest yields of three detected components of BXN, rutaecarpine, eugenol and cinnamaldehyde were observed in EE. EE showed the most remarkable antidiarrheal activity in dose-dependent and time-dependent manners in both senna- and castor oil-induced diarrhea models, and presented dose-dependent analgesic activity in acetic acid-induced algesthesia model. In addition, EE extract of BXN also exhibited strong antimobility action on the intestine and strongest depression on spontaneous contraction of isolated duodenum.ConclusionEthanol extraction is an efficient method to extract the active constituents of BXN. BXN extract demonstrated multiple pharmacological activities affecting the main mechanisms of diarrhea, which validated BXN's usage in the comprehensive clinical treatment of diarrhea.