Inhibitory effect of triterpenoids from the mushroom Inonotus obliquus against α-glucosidase and their interaction: Inhibition kinetics and molecular stimulations.

Bioassay-guided fractionation led to the isolation of a series of triterpenoids (1-46) including 12 new ones (1-12) from the mushroom Inonotus obliquus. The structures of all the compounds were elucidated by spectroscopic analysis as well as by comparison with literature data. Triterpenoids 1-3, 6, 7, 16, 24, 25, 27, 38, 43, 44 and 46 showed strong α-glucosidase inhibition, with IC50 values from 11.5 to 81.8 µM. Their structure-activity relationships were discussed. Inonotusol F (24) showed the strongest inhibitory activity and it presented noncompetitive inhibition against α-glucosidase. Molecular docking and molecular dynamics stimulation further demonstrated that GLU302 and PHE298 were key amino acids for the inhibition of inonotusol F (24) towards α-glucosidase. This study indicates the vital role of triterpenoids in explaining hypoglycemic effect of Inonotus obliquus and provides important evidence for further development and utilization of this mushroom.

A Mycochemical Investigation of the Black Lingzhi Mushroom, Amauroderma rugosum (Agaricomycetes), Reveals Several Lipidic Compounds with Anti-Inflammatory and Antiproliferative Activities.

A mycochemical investigation on the medicinal mushroom Amauroderma rugosum led to the isolation of 30 compounds, including 14 sterols, 6 phenolic constituents, 5 unsaturated fatty acids, and 5 other compounds. The structures of these compounds were elucidated by comparison of their nuclear magnetic resonance spectroscopic and mass spectrometry data with literature data. Among them, compound 27 was obtained as a new natural compound, and compounds 2-4, 7-13, and 15-30 were isolated from the genus Amauroderma for the first time. Sterols and unsaturated fatty acids showed anti-inflammatory and antiproliferative activities in vitro. Compounds 5 and 6 showed the highest inhibitory effect on nitric oxide production in lipopolysaccharide-induced murine macrophage RAW264.7 cells, with half maximal inhibitory concentration (IC50) values of 27.6 ± 2.1 µM and 15.3 ± 2.0 µM respectively. Compound 17 exhibited the strongest inhibition against HepG2 and MDA-MB-231 cell lines, with IC50 values < 25 µM. This study not only enriches the understanding of the diversity of chemical constituents in A. rugosum, but it also provides a basis for further development and utilization of A. rugosum as a source of new potential antitumor or anti-inflammatory chemotherapy agents.

Inhibitory Effect of Five Ganoderma Species (Agaricomycetes) against Key Digestive Enzymes Related to Type 2 Diabetes Mellitus.

Ganoderma mushrooms are widely used in clinical therapies and functional foods. The antidiabetic effect of Ganoderma has become a research hot spot in recent decades. To search for a superior antidiabetic Ganoderma extract, five common Ganoderma species (G. lucidum, G. sinense, G. tsugae, G. applanatum, and G. leucocontextum) were investigated. A total of 10 fractions, including a total triterpenes fraction and a crude polysaccharides fraction for each, were prepared for further assays. Activities of α-glucosidase and α-amylase are inhibited dominantly by triterpenes from all five Ganoderma species rather than the polysaccharides. G. lucidum triterpenes inhibits α-glucosidase and α-amylase most significantly with IC50 values of 10.02 ± 0.95 µg/mL and 31.82 ± 4.30 µg/mL. Even more, triterpenes content was positively correlated with anti-α-glucosidase and anti-α-amylase activities. Therefore, triterpenes were considered to be the active compounds in inhibiting α-glucosidase and α-amylase activity. It is hoped that the results will provide more systematic information for the application of Ganoderma in the functional food and traditional medicine industries in the future.

Two new γ-pyrone glucosides from Paeonia albiflora.

Two new γ-pyrone glucosides, along with three known compounds, were isolated from the roots of Paeonia albiflora, and their structures were elucidated by spectral experiments, chemical analysis, and comparison with literature data. The structures of the new compounds were established as 2-(hydroxymethyl)-4-oxo-4H-pyran-3-yl-6-O-α-L-rhamnopyranosyl-ß-D-glucopyranoside (1), and 2-(hydroxymethyl)-4-oxo-4H-pyran-3-yl-6-O-galloyl-ß-D-glucopyranoside (2). The inhibitory activity on the release of TNF-α of compounds 1-5 was evaluated in vitro. This is the first report of the presence of γ-pyrone glucoside in P. albiflora.

Five new diarylheptanoids from the rhizomes of Curcuma kwangsiensis and their antiproliferative activity.

Five new diarylheptanoids (1-5), along with nine known ones (6-14), were isolated from the rhizomes of Curcuma kwangsiensis. Their structures were established on the basis of spectroscopic analyses. Compounds 1-3 were cyclic diarylheptanoids rarely discovered from C. kwangsiensis. Of all the isolated compounds, compound 4 showed moderate antiproliferative activity on HH and HaCaT cells.

Identification and quantitative characterization of PSORI-CM01, a Chinese medicine formula for psoriasis therapy, by liquid chromatography coupled with an LTQ Orbitrap mass spectrometer.

PSORI-CM01 is a Chinese medicine formula prepared from medicinal herbs and used in China for the treatment of psoriasis. However, the chemical constituents in PSORI-CM01 have not been clarified yet. In order to quickly define the chemical profiles and control the quality of PSORI-CM01 preparations, ultra-high liquid chromatography coupled with electrospray ionization hybrid linear trap quadrupole Orbitrap mass spectrometry (UHPLC-ESI-LTQ/Orbitrap-MS) was applied for simultaneous identification and quantification of multiple constituents. A total of 108 compounds, including organic acids, phenolic acids, flavonoids, and terpenoids, were identified or tentatively deduced on the base of their retention behaviors, MS and MSn data, or by comparing with reference substances and literature data. In addition, an optimized UHPLC-ESI-MS method was established for the quantitative determination of 14 marker compounds in different dosage forms of PSORI-CM01 preparations. The validation of the method, including spike recoveries, linearity, sensitivity (LOQ), precision, and repeatability, was carried out and demonstrated to be satisfied the requirements of quantitative analysis. This is the first report on the comprehensive determination of chemical constituents in PSORI-CM01 preparations by UHPLC-ESI-LTQ/Orbitrap mass spectrometry. The results suggested that the established methods would be a powerful and reliable analytical tool for the characterization of multi-constituents in complex chemical system and quality control of TCM preparations.

Qualitative and quantitative analysis of Rhizoma Smilacis glabrae by ultra high performance liquid chromatography coupled with LTQ OrbitrapXL hybrid mass spectrometry.

Rhizoma Smilacis glabrae, a traditional Chinese medicine (TCM) as well as a functional food, has been commonly used for detoxification treatments, relieving dampness and as a diuretic. In order to quickly define the chemical profiles and control the quality of Smilacis glabrae, ultra high performance liquid chromatography coupled with electrospray ionization hybrid linear trap quadrupole orbitrap mass spectrometry (UHPLC-ESI/LTQ-Orbitrap-MS) was applied for simultaneous identification and quantification of its bioactive constituents. A total of 56 compounds, including six new compounds, were identified or tentatively deduced on the basis of their retention behaviors, mass spectra, or by comparison with reference substances and literature data. The identified compounds belonged to flavonoids, phenolic acids and phenylpropanoid glycosides. In addition, an optimized UHPLC-ESI/LTQ-Orbitrap-MS method was established for quantitative determination of six marker compounds from five batches. The validation of the method, including linearity, sensitivity (LOQ), precision, repeatability and spike recoveries, was carried out and demonstrated to be satisfied the requirements of quantitative analysis. The results suggested that the established method would be a powerful and reliable analytical tool for the characterization of multi-constituent in complex chemical system and quality control of TCM.

Anti HSV-1 flavonoid derivatives tethered with houttuynin from Houttuynia cordata.

This paper reports the phytochemical investigation of the 50% aq. EtOH extract of Houttuynia cordata, an effective TCM and functional food in China, which led to the isolation of 17 flavonoids including four new ones. The four new compounds were flavonoid derivatives tethered with houttuynin (3-oxododecanal). Each of the new compounds was obtained as a pair of inseparable diasteriomeric epimers due to the chiral carbon of hemiketal at C-3″. This phenomenon is rooted in the ring-chain tautomerism of the hemiketal functional group in solution, which was proved by dynamic NMR experiments. The new compounds 1-4 displayed inhibitory activities against herpes simplex virus 1, with respective IC50 values of 38.46, 14.10, 62.00 and 70.76 µM, which was associated with the medicinal functions of H. cordata.

Houttuynoids A-E, anti-herpes simplex virus active flavonoids with novel skeletons from Houttuynia cordata.

Houttuynoids A-E (1-5), a new type of flavonoid with houttuynin tethered to hyperoside, and their presumed biosynthetic precursor hyperoside (6) were isolated from the whole plant of Houttuynia cordata. Their structures were elucidated by analysis of 1D and 2D NMR. A hypothetical biogenetic pathway for houttuynoids A-E was proposed. Compounds 1-5 exhibited potent anti-HSV (herpes simplex viruses) activity.

Bidesmoside triterpenoid glycosides from Stauntonia chinensis and relationship to anti-inflammation.

Ten triterpenoid glycosides, yemuoside YM(26-35) (1-9 and 12), were isolated from a traditional Chinese medicine known as "Ye Mu Gua" (Stauntonia chinensis DC.) along with two known ones, kalopanax saponin C (10) and sieboldianoside A (11). Their structures, as elucidated by spectroscopic analyses and chemical methods, were either penta-saccharidic or hexa-saccharidic bidesmoside triterpenoid glycosides. To help explain the clinical applications of "Ye Mu Gua" for its anti-inflammatory effects, the inhibitory activity on the release of inflammatory mediators (nitric oxide, TNF-alpha and IL-6) of 1-12 and the related aglycone, hederagenin (13), was evaluated in vitro. It was found that compound 13, but not 1-12, exhibited significant inhibitory activity. The abundant triterpenoid glycosides in "Ye Mu Gua" might therefore be transformed into their respective aglycones, and thus inhibit the release of inflammatory factors in vivo. This could then account for the clinical value of "Ye Mu Gua" as regards anti-inflammatory effects. This proposed explanation of how "Ye Mu Gua" may have an effect is similar to the concept of prodrugs for chemical drugs which could be extended to some traditional medicines. That is, the major components might be biologically active not directly, but via biochemical transformation in vivo. Hence, we propose a "traditional medicine's prodrug characteristic" concept.