Five new chromone glycosides from Scindapsus officinalis (Roxb.) Schott

Secondary metabolites from Scindapsus officinalis (Roxb.) Schott. with in vitro antidiabetic activities

One new phenolic cyclobutantetraol ester united chromone glycoside (1), one new amide (2), and three new phenyl ethanol glycosides (3-5) were obtained from the water extract of Scindapsus officinalis (Roxb.) Schott, in which compound 1 was the first reported structure incorporating the phenolic cyclobutantetraol ester and chromone via the glucose phenolic metabolites in nature. Structures of the isolated compounds, including absolute configurations, were elucidated according to the analysis of HRESIMS, NMR, ECD and BLYP/6-31G* geometry optimization calculations of 13C NMR data. All isolates (1-5) were evaluated for the antidiabetic activity by the insulin resistance (IR) model and anti-inflammatory activity against NO production in vitro. Compounds 1-3 showed strong antidiabetic activities, greatly promoting the glucose consumption in the insulin resistance HepG2 cells compared with the model group, however, 1-5 showed weak anti-inflammatory activities.

Costunosides A-C: cytotoxic sesquiterpene lactones from the rhizomes of Aucklandia costus Falc

Three new eudesmane type rare sesquiterpene lactone galactosides, costunosides A-C (1-3) were isolated from the rhizomes of Aucklandia costus along with ten known compounds (4-13). Costunosides A-C (1-3) are the first example of naturally eudesmane glycosides containing a β-galactopyranoside moiety. The structure and relative configurations of these compounds were established by comprehensive analysis of MS and, in particular 1D/2D NMR spectroscopic data. The isolated compounds were tested against a panel of human cancer cell lines, where compounds 3, 6 and 7 have shown promising cytotoxic activity against PC-3, HCT-116 and A549 cell lines with IC50 values in the range of 3.4 µM to 9.3 µM, respectively. Costunosides A-C (1-3) were also screened for inhibition assay of acetyl-cholinesterase (AChE), and butyrylcholinesterase (BChE) and found inactive at a concentration of 10 µM.

Phytochemical Analysis, Antimutagenic and Antiviral Activity of Moringa oleifera L. Leaf Infusion: In Vitro and In Silico Studies

Moringa oleifera (M. oleifera) leaves are rich in nutrients and antioxidant compounds that can be consumed to prevent and overcome malnutrition. The water infusion of its leaf is the easiest way to prepare the herbal drink. So far, no information is available on the antioxidant, antimutagenic, and antivirus capacities of this infusion. This study aimed to determine the composition of the bioactive compounds in M. oleifera leaf infusion, measuring for antioxidant and antimutagenic activity, and evaluating any ability to inhibit the SARS-CoV-2 main protease (Mpro). The first two objectives were carried out in vitro. The third objective was carried out in silico. The phytochemical analysis of M. oleifera leaf infusion was carried out using liquid chromatography-mass spectrometry (LC-MS). Antioxidant activity was measured as a factor of the presence of the free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). The antimutagenicity of M. oleifera leaf powder infusion was measured using the plasmid pBR322 (treated free radical). The interaction between bioactive compounds and Mpro of SARS-CoV-2 was analyzed via molecular docking. The totals of phenolic compound and flavonoid compound from M. oleifera leaf infusion were 1.780 ± 5.00 µg gallic acid equivalent/g (µg GAE/g) and 322.91 ± 0.98 µg quercetin equivalent/g (µg QE/g), respectively. The five main bioactive compounds involved in the infusion were detected by LC-MS. Three of these were flavonoid glucosides, namely quercetin 3-O-glucoside, kaempferol 3-O-neohesperidoside, and kaempferol 3-α-L-dirhamnosyl-(1→4)-β-D-glucopyranoside. The other two compounds were undulatoside A, which belongs to chromone-derived flavonoids, and gentiatibetine, which belongs to alkaloids. The antioxidant activity of M. oleifera leaf infusion was IC50 8.19 ± 0.005 µg/mL, which is stronger than the standard butylated hydroxytoluene (BHT) IC50 11.60 ± 0.30 µg/mL. The infusion has an antimutagenic effect and therefore protects against deoxyribonucleic acid (DNA) damage. In silico studies showed that the five main bioactive compounds have an antiviral capacity. There were strong energy bonds between Mpro molecules and gentiatibetine, quercetin, undulatoside A, kaempferol 3-o-neohesperidoside, and quercetin 3-O-glucoside. Their binding energy values are −5.1, −7.5, −7.7, −5.7, and −8.2 kcal/mol, respectively. Their antioxidant activity, ability to maintain DNA integrity, and antimutagenic properties were more potent than the positive controls. It can be concluded that leaf infusion of M. oleifera does provide a promising herbal drink with good antioxidant, antimutagenic, and antivirus capacities.

Naturally Occurring Chromone Glycosides: Sources, Bioactivities, and Spectroscopic Features

Chromone glycosides comprise an important group of secondary metabolites. They are widely distributed in plants and, to a lesser extent, in fungi and bacteria. Significant biological activities, including antiviral, anti-inflammatory, antitumor, antimicrobial, etc., have been discovered for chromone glycosides, suggesting their potential as drug leads. This review compiles 192 naturally occurring chromone glycosides along with their sources, classification, biological activities, and spectroscopic features. Detailed biosynthetic pathways and chemotaxonomic studies are also described. Extensive spectroscopic features for this class of compounds have been thoroughly discussed, and detailed 13C-NMR data of compounds 1-192, have been added, except for those that have no reported 13C-NMR data.

Extraction of Flavonoids from Scutellariae Radix using Ultrasound-Assisted Deep Eutectic Solvents and Evaluation of Their Anti-Inflammatory Activities

Deep eutectic solvents (DESs) play important roles in the extraction of active constituents in traditional Chinese medicine. Ultrasound-assisted DES has been used to extract flavonoids from Scutellaria baicalensis. Using the contents of scutellarin, baicalin, baicalein, wogonoside, wogonin, and oroxylin A as quantitative indices, different kinds of DESs have been optimized for extraction and betaine/acetic acid has shown the highest yield. The Box-Behnken response surface method (RSM) was utilized to select the extraction conditions with the highest yields. The optimal extraction conditions were as follows: the molar ratio of betaine/acetic acid was 1:4, the water content was 40%, the solid/liquid ratio was 1:100 g/mL, the extraction temperature was 52 °C, and the extraction time was 23 min. Compared with traditional reflux extraction using 70% ethanol as the solvent, ultrasound-assisted DES has a shorter extraction time and higher yields. Furthermore, anti-inflammatory activities of the two extracts by ultrasound-assisted DES and reflux were compared using RAW264.7 cells and the methyl thiazolyl tetrazolium (MTT) method, and they showed equal anti-inflammatory activities. The results demonstrated that the ultrasound-assisted DES method for extraction of flavonoids from scutellariae radix is simple, green, efficient, and reproducible. This research provides good method guides for the rapid and efficient extraction of flavonoids from natural sources.

An efficient method to obtain anti-inflammatory phenolic derivatives from Scindapsus officinalis (Roxb.) Schott. by a high speed counter-current chromatography coupled with a recycling mode

Herein, we provide an effective separation strategy based on liquid–liquid extraction and two different modes of high speed counter-current chromatography (HSCCC) for the rapid enrichment and separation of compounds from n-butanol-partitioned samples of S. officinalis. Liquid–liquid extraction of the crude sample was performed using a two-phase solvent system composed of ethyl acetate–n-butanol–water with volume ratios of 9 : 0 : 9, 5 : 4 : 9 and 3 : 6 : 9 (v/v), which allowed components with lower polarity and higher polarity to be enriched separately with the first ratio and the other two ratios, respectively. For separation, the conventional and recycling mode HSCCC were combined to develop a strategy for the acquisition of eight phenolic derivatives from the enriched samples, including one new compound, 7-O-[β-d-xylopyranosyl-(1–4)-β-d-glucopyranosyl-(1–4)-α-l-rhamnopyranosyl]-5-hydroxy-2-methyl-4H-1-benzopyran-4-one (5), three caffeoylquinic acid isomers, 3-O-caffeoylquinic acid butyl ester (6), 5-O-caffeoylquinic acid butyl ester (7), 4-O-caffeoylquinic acid butyl ester (8), salidroside (1), drynachromoside B (2), 3,4-dihydroxy-benzoic acid (3), and 5,7-dihydroxy-2-methyl chromone (4). Recycling HSCCC separation was successfully applied to separate the three isomers after six cycles. Furthermore, all the isolates were evaluated for their anti-inflammatory activity against nitric oxide (NO) production in vitro, with 6 and 7 showing significant inhibitory effects with IC₅₀ values of 13.8 μM and 17.6 μM, respectively.

Anti-inflammatory phenolic derivatives from S. officinalis by high speed counter-current chromatography.

Alkaloids from Melodinus henryi with anti-inflammatory activity

One new quinolinic scandine-type monoterpeniod alkaloid, 3-oxo-scandine (1), as well as seven known ones (2-8), was isolated from the roots of Melodinus henryi. Their structures were elucidated by extensive spectroscopic analysis. All of the compounds were prepared and evaluated for their anti-inflammatory activities by measuring the inhibitory activity of nitric oxide (NO) in vitro in RAW 264.7 mouse peritoneal macrophages. Compounds 6 and 7 showed significant activities with IC₅₀ values of 8.54 and 5.19 μM, respectively.

Chemical Constituents from Scindapsus officinalis (Roxb.) Schott. and Their Anti⁻Inflammatory Activities

One new monoterpene glycoside (1), one new phenyl glycoside (2), one new caffeoyl derivative (3), were isolated from Scindapsus officinalis (Roxb.) Schott., along with four known compounds (4–7). Structures of the isolated compounds were elucidated by extensive analysis of spectroscopic data, especially 2D NMR data and comparison with literatures. All isolates were evaluated for anti-inflammatory activity against nitric oxide (NO) production in vitro. Compounds 3 and 7 exhibited moderate inhibitory effects on NO production with IC₅₀ values of 12.2 ± 0.8 and 18.9 ± 0.3 μM, respectively.

Ethyl Acetate Extract of Scindapsus cf. hederaceus Exerts the Inhibitory Bioactivity on Human Non-Small Cell Lung Cancer Cells through Modulating ER Stress

Unfolded protein response (UPR) is a cytoprotective mechanism that alleviates the protein-folding burden in eukaryotic organisms. Moderate activation of UPR is required for maintaining endoplasmic reticulum (ER) homeostasis and profoundly contributes to tumorigenesis. Defects in UPR signaling are implicated in the attenuation of various malignant phenotypes including cell proliferation, migration, and invasion, as well as angiogenesis. This suggests UPR as a promising target in cancer therapy. The pharmacological effects of the plant Scindapsus cf. hederaceus on human cancer cell lines is not understood. In this study, we identified an ethyl acetate extract from Scindapsus cf. hederaceus (SH-EAE), which markedly altered the protein expression of UPR-related genes in human non-small cell lung cancer (NSCLC) cells. Treatment with the SH-EAE led to the dose-dependent suppression of colony forming ability of both H1299 and H460 cells, but not markedly in normal bronchial epithelial BEAS-2B cells. SH-EAE treatment also attenuated the migration and invasion ability of H1299 and H460 cells. Moreover, SH-EAE strikingly suppressed the protein expression of two ER stress sensors, including inositol requiring enzyme-1α (IRE-1α) and protein kinase R-like ER kinase (PERK), and antagonized the induction of C/EBP homologous protein (CHOP) expression by thapsigargin, an ER stress inducer. SH-EAE induced the formation of massive vacuoles which are probably derived from ER. Importantly, SH-EAE impaired the formation of intersegmental vessels (ISV) in zebrafish larvae, an index of angiogenesis, but had no apparent effect on the rate of larval development. Together, our findings demonstrate, for the first time, that the ability of SH-EAE specifically targets the two sensors of UPR, with significant anti-proliferation and anti-migration activities as a crude extract in human NSCLC cells. Our finding also indicates potential applications of SH-EAE in preventing UPR activation in response to Tg-induced ER stress. We suggest that SH-EAE attenuates UPR adaptive pathways for rendering the NSCLC cells intolerant to ER stress.

Chemical Constituents of the Ethyl Acetate Extract from Diaphragma juglandis Fructus and Their Inhibitory Activity on Nitric Oxide Production In Vitro

Diaphragma juglandis fructus contains various bioactive constituents. Fourteen compounds were isolated from Diaphragma juglandis fructus by preparative high performance liquid chromatography (pre-HPLC) and high-speed counter-current chromatography (HSCCC). Their structures were identified by nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESI-MS). Compounds (+)-dehydrovomifoliol (12), (6R,9R)-9-hydroxymegastigman-4-en-3-one (13) and (6R,9S)-9-hydroxymegastigman-4-en-3-one (14) are found from Juglans regia L. for the first time. Compounds dihydrophaseic acid (2), blumenol B (3) and (4S)-4-hydroxy-1-tetralone (11) are isolated from Diaphragma juglandis fructus for the first time. The anti-inflammatory effects of isolated compounds were evaluated by an in vitro model of lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Compounds gallic acid (1), ethyl gallate (9) and (+)-dehydrovomifoliol (12) exhibited inhibitory activity on the nitric oxide production of RAW 264.7 at a concentration of 25 μM. The result indicated that the combination HSCCC with pre-HPLC is an effective way for compound separation and purification. And Diaphragma juglandis fructus constituents have the potential for the treatment of inflammatory-related diseases.