Renoprotective Mono- and Triterpenoids from the Fruit of Gardenia jasminoides

Chemical constituents from the stems of Ephedra intermedia and their α-glucosidase and AChE inhibitory effects

Five undescribed glycosides (1-5) and eight known compounds (6-13) were isolated from the stems of Ephedra intermedia. Their chemical structures were determined by analysis of NMR, ECD, and MS data. In addition, The in vitro bioactive assay, α-glucosidase and acetylcholinesterase (AChE) inhibitory activities, suggested that compounds 11 and 12 exhibited obvious inhibitory effects on α-glucosidase with the IC50 value of 49.51 ± 0.97 μM and 47.12 ± 0.98 μM, respectively, compounds 4 and 5 showed weak inhibitory effects on AChE at the concentration of 100 μM.

Diketopiperazine and purine alkaloids from the tubers of Pinellia pedatisecta Schott and their protective activities against Aβ25-35-induced PC-12 cell injury

Nine undescribed diketopiperazine alkaloids (1-8, 28) and three undescribed purine alkaloids [35, (±)-36, (±)-37], along with twenty-six known compounds, were isolated from the tubers of Pinellia pedatisecta Schott. Their structures were determined by analysis of their 1D and 2D NMR spectra, HRESIMS, DP4+, ECD, and optical rotation data. In addition, the protective effects of all compounds against Aβ25-35-induced PC-12 cell injury were evaluated by MTT assay. The results showed that compounds 2-4, 8, 9, 12, 13, 15, 17-20, 23, 24, 26, 28, 30-32 and 38 exhibited significantly protective effects and had potential anti-Alzheimer's disease activity.

Alkaloids with Their Protective Effects Against Aβ25-35-Induced PC-12 Cell Injury from the Tubers of Pinellia pedatisecta Schott

Seven new alkaloids [1, (±)-2, (±)-3, 4, and 5] and one new natural product (6), along with eight known analogues, were isolated from the tubers of Pinellia pedatisecta Schott. Their structures were determined by a comprehensive analysis of spectroscopic data, including HRESIMS, and electronic circular dichroism (ECD). In addition, the results of the bioactivity evaluation showed that compounds (±)-3, 6, and 9 exhibited significantly protective effects against Aβ25-35-induced PC-12 cell injury and ameliorated cell viabilities by decreasing the levels of the reactive oxidative species (ROS) and mitochondrial membrane potential (MMP).

A metabolomics study on the mechanisms of Gardeniae fructus against α-naphthylisothiocyanate-induced cholestatic liver injury

Gardeniae fructus (GF) is known for its various beneficial effects on cholestatic liver injury (CLI). However, the biological mechanisms through which GF regulates CLI have not been fully elucidated. This study aimed to explore the potential mechanisms of GF against α-naphthylisothiocyanate (ANIT)-induced CLI. First, HPLC technology was used to analyze the chemical profile of the GF extract. Second, the effects of GF on serum biochemical indicators and liver histopathology were examined. Lastly, metabolomics was utilized to study the changes in liver metabolites and clarify the associated metabolic pathways. In chemical analysis, 10 components were identified in the GF extract. GF treatment regulated serum biochemical indicators in ANIT-induced CLI model rats and alleviated liver histological damage. Metabolomics identified 26 endogenous metabolites as biomarkers of ANIT-induced CLI, with 23 biomarkers returning to normal levels, particularly involving primary bile acid biosynthesis, glycerophospholipid metabolism, tryptophan metabolism, and arachidonic acid metabolism. GF shows promise in alleviating ANIT-induced CLI by modulating multiple pathways.

Chemical constituents from stipes of Lentinus edodes and their protective effects against Aβ25-35-induced N9 microglia cells injury

Nine undescribed compounds, along with eight known compounds, were isolated from the stipes of Lentinus edodes. Their structures were established by extensive spectroscopic and circular dichroism analyses. The protective effects against Aβ25-35-induced N9 microglia cells injury of these compounds were tested by MTT method, and the levels of apoptosis and ROS were detected by flow cytometry. In addition, the binding sites and interactions of compound with amyloid precursor protein were revealed using molecular docking simulations. These findings further establish the structural diversity and bioactivity of stipes of L. edodes, and provide an experimental basis for targeting Alzheimer's disease as a potential strategy.

Four pairs of tautomers from rhizomes of Acorus calamus and fruits of Cornus officinalis

A pair of new guaiane-type sesquiterpene tautomers (1) was isolated from rhizomes of Acorus calamus. Meanwhile, three pairs of known compounds, including a pair of dihydroflavone glycoside tautomers (2), a pair of 4-hydroxybenzoic acid ester glycoside tautomers (3), as well as a pair of secoiridoid glycoside tautomers (4) were isolated from fruits of Cornus officinalis. Their structures were elucidated by extensive spectroscopic and computational methods. Furthermore, the tautomeric mechanisms were discussed.

A new flavonoid from the thorn of Gleditsia sinensis Lam

A new flavonoid, (2'''E,6'''S)-4''-(6-hydroxy-2,6-dimethylocta-2,7-dienoyl)-vitexin (1), and five known compounds (2-6) were isolated from the thorn of Gleditsia sinensis Lam. Their structures were determined by comprehensive and comparative spectroscopic analysis of NMR and MS data. The absolute configuration of the new compound was deduced by analysis of the experimental and calculated ¹³C NMR data. The protective effects against lipopolysaccharide (LPS)-induced apoptosis in normal rat kidney tubule epithelioid (NRK 52e) cells of the isolated compounds were investigated in vitro, whose results showed that compound 1 showed significant protective effect with the EC₅₀ value of 3.0 μM.

Minor iridoid glycosides from the fruits of Cornus officinalis Sieb. et Zucc. and their anti-diabetic bioactivities

Fifteen previously undescribed minor iridoid glycosides, including four monomers and eleven dimers, were isolated from the fruits of Cornus officinalis Sieb. et Zucc. Their chemical structures were determined on the basis of spectroscopic data and chemical evidence. All of the isolated compounds were evaluated for their effects of the glucose consumption on the insulin resistant HepG2 cells, and four compounds, named cornuofficinalisides F, H, L, and O, increased the glucose consumption significantly at 10 μM, the EC₅₀ values of them were determined to be 0.898, 1.625, 0.923, and 8.589 μM, respectively. Moreover, the four compounds could improve the ability of glucose uptake significantly in insulin resistant HepG2 cells.

Chemical Constituents from the Flowers of Carthamus tinctorius L. and Their Lung Protective Activity

A new flavonoid, saffloflavanside (1), a new sesquiterpene, safflomegastigside (2), and a new amide, saffloamide (3), together with twenty-two known compounds (4-25), were isolated from the flowers of Carthamus tinctorius L. Their structures were determined based on interpretation of their spectroscopic data and comparison with those reported in the literature. The protective effects against lipopolysaccharide (LPS)-stimulated damage on human normal lung epithelial (BEAS-2B) cells of the compounds were evaluated using MTT assay and cellular immunofluorescence assay. The results showed that compounds 2-3, 8-11, and 15-19 exhibited protective effects against LPS-induced damage to BEAS-2B cells. Moreover, compounds 2-3, 8-11, and 15-19 can significantly downregulate the level of nuclear translocation of NF-κB p-p65. In summary, this study revealed chemical constituents with lung protective activity from C. tinctorius, which may be developed as a drug for the treatment of lung injury.

Quality Evaluation of Decoction Pieces of Gardeniae Fructus Based on Qualitative Analysis of the HPLC Fingerprint and Triple-Q-TOF-MS/MS Combined with Quantitative Analysis of 12 Representative Components

In this study, quality evaluation (QE) of 40 batches of decoction pieces of Gardeniae Fructus (GF) produced by different manufacturers of herbal pieces was performed by qualitative analysis of the HPLC fingerprint and ultra-fast liquid chromatography (UFLC)-triple-Q-TOF-MS/MS combined with quantitative analysis of multiple components, which we established previously for QE of traditional medicine. First, HPLC fingerprints of 40 samples were determined, and the common peaks in the reference fingerprint were assigned. Second, the components of the common peaks in the HPLC fingerprints were identified by UFLC-triple-Q-TOF-MS/MS. Finally, the contents of the components confirmed by reference substances were measured. The results showed that there were 28 common peaks in the HPLC fingerprints of 40 samples. The components of these 28 common peaks were identified as 13 iridoids, 4 crocins, 7 monocyclic monoterpenoids, 3 organic acids, and 1 flavonoid. Of these, a total of 12 components, including 7 iridoids of geniposide, shanzhiside, geniposidic acid, deacetyl asperulosidic acid methyl ester, gardenoside, scandoside methyl ester, and genipin gentiobioside, 2 crocins such as crocin I and crocin II, 1 monocyclic monoterpenoid of jasminoside B, 1 organic acid of chlorogenic acid, and 1 flavonoid of rutin, were unambiguously identified by comparison with reference substances. There were certain differences in the contents of these 12 components among 40 samples. The geniposide content ranged from 37.917 to 72.216 mg/g, and the total content of the 7 iridoids ranged from 59.931 to 94.314 mg/g.

Iridoid glycosides and lignans from the fruits of Gardenia jasminoides Eills

Four previously undescribed iridoid glycosides, including two bis-iridoid glycosides, and three undescribed lignans, together with 16 known analogues, were isolated from the fruits of Gardenia jasminoides Eills. Their structures were elucidated on basis of spectroscopic methods, and the absolute configurations of three of the unknown compounds were determined by interpretation of their electronic circular dichroic (ECD) and [α] [Formula: see text] data. The α-glucosidase inhibitory effects of the isolated compounds were evaluated and all the compounds exhibited slightly inhibitory activity with the values of IC₅₀ greater than 50 μM.

A critical review on the use of DP4+ in the structural elucidation of natural products: the good, the bad and the ugly. A practical guide

Covering: 2015 up to the end of 2020Even in the golden age of NMR, the number of natural products being incorrectly assigned is becoming larger every day. The use of quantum NMR calculations coupled with sophisticated data analysis provides ideal complementary tools to facilitate the elucidation process in challenging cases. Among the current computational methodologies to perform this task, the DP4+ probability is a popular and widely used method. This updated version of Goodman's DP4 synergistically combines NMR calculations at higher levels of theory with the Bayesian analysis of both scaled and unscaled data. Since its publication in late 2015, the use of DP4+ to solve controversial natural products has substantially grown, with several predictions being confirmed by total synthesis. To date, the structures of more than 200 natural products were determined with the aid of DP4+. However, all that glitters is not gold. Besides its intrinsic limitations, on many occasions it has been improperly used with potentially important consequences on the quality of the assignment. Herein we present a critical revision on how the scientific community has been using DP4+, exploring the strengths of the method and how to obtain optimal results from it. We also analyze the weaknesses of DP4+, and the paths to by-pass them to maximize the confidence in the structural elucidation.

A new quinic acid derivative with α-glucosidase inhibitory activity from the fruit of Gardenia jasminoides J.Ellis

A new quinic acid derivative (1) along with seven known compounds (2-8) were isolated from the fruit of Gardenia jasminoides J.Ellis. All the structures of the isolated compounds were elucidated on the basis of the analysis of multiple spectroscopic data. The α-glucosidase inhibitory effects of the isolated compounds were investigated. The results showed that compounds 1-3, 6, and 8 have moderate α-glucosidase inhibitory activities.

Two new iridoid glycosides from Gardeniae Fructus

Two new iridoid glycosides, genipin 1,10-di-O-α-l-rhamnoside (1) and genipin 1,10-di-O-β-d-xylopyranoside (2), along with thirteen known compounds (3-15) were isolated from Gardeniae Fructus. Their structures were elucidated by physical data analyses such as NMR, UV, IR, HR-ESI-MS, as well as chemical hydrolysis. All compounds were tested for their tyrosinase inhibitory and antioxidant activities. At a concentration of 25 μM, compound 13 showed obvious mushroom tyrosinase inhibition activity with % inhibition value of 36.52 ± 1.98%, with kojic acid used as the positive control (46.09 ± 1.29%). At a concentration of 1 mM, compounds 8 and 9 exhibited considerable DPPH radical scavenging activities, with radical scavenging rates of 48.54 ± 0.47%, 58.59 ± 0.39%, respectively, with l-ascorbic acid used as the positive control (59.02 ± 0.77%).