Natural Product Research最新文献

The leaves of Cyclocarya paliurus (Batal) Iljinsk., a plant native to China that has long been used in traditional Chinese medicine to treat diabetes. It remains to be determined what chemical constituents are responsible for this effect. The aim of this study was to identify the antidiabetic components of C. paliurus using the spectrum-effect relationship and confirmed using molecular docking. The components of C. paliurus were detected using ultra-high-performance liquid chromatography mass spectrometry/mass spectrometry (UHPLC-MS/MS) and ultra-high-performance liquid chromatography-diode array detector (UHPLC-DAD). C. paliurus could significantly reduce glycosylated haemoglobin, blood glucose levels and blood lipid profile. Esculetin, shikimic acid, isoquercitrin, quercitrin, kaempferol-3-O-rhamnoside, tricin, and pterocaryoside A were determined to be the main antidiabetic components of C. paliurus. Results revealed that the antidiabetic effect of C. paliurus was due to the combination of multiple chemical components. The method developed is valuable for identifying the active ingredients of this plant species.

Lectins are naturally occurring agglutinins which are produced more from plants sources compared to animal sources. The present study aims to screen the potential applications of lectin isolated from the mangrove plant, Rhizophora mucronata Poir. This root agglutinin of R. mucronata showed highest HA titre with buffalo erythrocytes. The agglutinin activity was pH dependent, thermolabile, calcium dependent and sensitive to divalent EDTA chelators. The agglutinability was dominantly inhibited by simple sugars, glucose and melibiose. The agglutinin was partially purified by biospecific adsorption using formalinized buffalo erythrocytes yield 21.81 fold increase in activity. Purified R. mucronata root lectin (RmrL) showed cytotoxic activity against HeLa (Cervical cancer) cell lines (IC₅₀ value-161.305 µg/ml) and also exhibited antimicrobial activity against multidrug resistant bacterial strains.

Capsaicin is the primary bioactive constituent in chillies, responsible for its incomparable pungent taste and many health advantages. In the current study, 32 samples of three different species of Capsicum (Capsicum annuum L., Capsicum frutescens L., Capsicum chinense Jacq.) from various geographical regions in Northeast India were evaluated for their total capsaicin content by high performance thin layer chromatography (HPTLC). An excellent separation of capsaicin (R_f = 0.268 ± 0.02) was obtained using toluene and ethyl acetate as mobile phase at a 7:3 (v/v) ratio. The calibration curve was described by the equation Y = 5.661 × 10^-9X + 1.225 × 10^-4 with a correlation coefficient (r) of 0.99894. The percentage of capsaicin was found to range from 1.99 to 24.48% w/w. The linearity range for the curve for capsaicin was found 200-1000 ng per spot. The limit of detection and quantification were determined to be 45.98 and 97.70 ng, respectively. The proposed validated HPTLC method may be used for routine quality testing and quantification of capsaicin in chilli samples.

Alpha-mangostin (AM) is a naturally occurring xanthone with remarkable pharmacological properties, including anti-inflammatory, anti-bacterial, and antioxidant effects. The compound is commonly extracted from the pericarps of Garcinia mangostana L. fruits, but its seasonal availability is limited. Investigating the potential of using various organs of the tree for AM extraction can help mitigate limitations imposed by the seasonal availability of fruits. This study employs the Soxhlet extraction method and gravitational column chromatography for the preparation of AM from various plant organs. The purity of the compound in the extract was quantitatively determined using high-performance liquid chromatography analysis. The stem barks demonstrated the highest yield at 1.3%, with a concentration of 324.593 µg/mL and a purity of 95.215% for AM. The finding is expected to assist in uncovering alternative sources of AM and contribute to sustainable utilisation of the tree, as various plant organs could be employed in AM extraction.

A new megastigmane glycoside, conspurcoside A (1), two new phenol glycosides, conspurcosides B (2) and C (3), along with twelve known compounds (4 - 15) were isolated from the bark of Mallotus conspurcatus Croizat. The structures of these compounds were identified through analysis of spectroscopic data, including 1D and 2D NMR, HRESIMS, and ECD methods. Compounds (1 -6, 14 - 15) were tested for inhibition of NO production in lipopolysaccharide (LPS)-induced RAW 264.7 cells to investigate their anti-inflammatory effects. The results revealed that compounds 2 and 3 demonstrated moderate inhibitory effects on NO production with IC₅₀ values of 42.36 μM and 44.81 μM.

Two new polyacetylenes, (5Z,12E)-14-hydroxytetradeca-5,12-dien-8,10-diyn-1-yl 3-methylbut-2-enoate (1) and 5S, 1'R-(6E,12E)-1-hydroxytetradeca-6,12-dien-8,10-diyn-5-yl 2-methylbutanoate (2), together with two known ones, (2E,8E)-12-β-methylbutyryltetradeca-2,8-diene-4,6-diyne-1,14-diol (3), and (E)-5-[5-(but-3-en-1-yn-1-yl)thiophen-2-yl]pent-2-en-4-yn-1-yl acetate (4) were isolated from the ethyl acetate extract of the roots of Atractylodes macrocephala by various chromatographic methods, such as normal phase silica gel column, MPLC, and semi-preparative HPLC. Their structures were identified by kinds of spectroscopic methods including 1D NMR, 2D NMR, IR, UV, HR-ESI-MS, and ECD. Compound 1 exhibited cytotoxic activities in HepG2 and Huh7 cells with IC₅₀ values of 20.50 ± 2.07 and 19.99 ± 1.35 μM, respectively.

Embelin (EMB) and Piperine (PIP) alkaloids are reported for -antidiabetic, hypolipidemic, antioxidant, and anti-cancer properties. However, simultaneous analytical methods are scarce. A stability-indicating RP-HPLC method was developed with mobile phase MeOH: 0.1%TEA (pH 4.2 adjusted by OPA) (92:08 v/v ratio), CHEMSIL-ODS, C₁₈ (4.6 × 250mm, 5 µm) column, and 1.2 mL/min -flowrate. Retention times were 3.2, and 6.2 min for PIP and EMB respectively, at 289 nm, and validated as per Q2 (R1) ICH guidelines. Linearity ranging (2-10 µg/mL), with regression coefficients (r²), LOD, and LOQ for PIP were r² = 0.9979, 0.793 µg/mL, 2.403 µg/mL, and r² = 0.9974, 0.851 µg/mL, 2.578 µg/mL for EMB. Developed method precision, robustness, and ruggedness were confirmed by <2%RSD. In tablet and capsule formulations, PIP %purity was 90.36%, 94.33%, and EMB 91.65, 92.85%. Additionally, forced-degradation studies -indicated method stability through various stressed conditions. Hence, this -validated method is specific, precise, linear, accurate, and robust, -suitable for routine analysis of EMB and PIP in polyherbal -formulations containing Embelia ribes Brum. and Piper nigrum Linn. extracts.

Gemcitabine (GEM) is an antitumor drug approved by the US FDA in 1996. It is used to treat cancer and solid tumours, but its effectiveness is limited by toxicity. Carboxymethyl-β-1,3-D-glucan (CMG) is a derivative of β-glucan with improved solubility. In a study, GEM was conjugated to CMG (GG) with a stable amino acid linker to enhance efficacy and reduce toxicity. GG showed significant inhibition on LLC tumour cells with IC₅₀ value of 2.7 compared to GEM at 0.5248, and was less toxic to normal cells. In C57BL/6 mice, GG had anti-lung cancer effects in vitro and in vivo by decreasing expression of apoptosis-related proteins. The study indicates GG's potential as an anti-tumour drug for lung cancer with reduced toxicity, paving the way for further research.

This study presents the first complete analysis of the chemical composition of the flowers of the species N. fragrans and N. microchila. The compounds were extracted via distillation and simultaneous extraction and analysed using gas chromatography coupled to mass spectrometry. A total of 82 compounds were identified and the results reveal significant differences in the abundance of compounds between the species. While N. fragrans has eugenol as its majority compound, N. microchila exhibits high concentrations of (E)-β-farnesene. In addition, remarkable concentrations of secondary compounds such as methyl-eugenol, β-bisabolene, germacrene D, 1-octadecene, hexadecyl acetate and ipsdienol were observed and are demonstrably related to the processes of attraction of pollinators, such as euglossine bees, by Orchidaceae. The findings of the study offer valuable insights into the ecology and reproductive biology of the species studied, and also present taxonomic potential for the phytochemical data.

This study compared gallic acid (GLA) and its derivatives, i.e. ginnalin A (GA), 1,2,3,4,6-penta-O-galloyl-β-D-glucose (PGG), and (-)-epigallocatechin-3-gallate (EGCG) on their ability against 6-hydroxydopamine (6-OHDA)-induced cytotoxicity. Their binding to the Kelch-like ECH-associated protein 1 (Keap1) Kelch domain was assessed using isothermal titration calorimetry (ITC) and molecular docking. Cellular assays, such as ROS quantification, In-Cell Western assay and quantitative real-time PCR (qRT-PCR) analysis, were performed using human neuroblastoma (SH-SY5Y) cells to investigate their involvement in the nuclear factor erythroid-2 related factor 2 (Nrf2)/Keap1 and the nuclear factor-κB (NF-κB) pathways. We found that these four natural products (NPs) can activate the Nrf2/Keap1 pathways with GLA exhibiting the highest and EGCG displaying the lowest activating capability. However, their inhibitory effects on the NF-κB pathway showed a different order of potencies, with EGCG exerting the least inhibitory effect. All these contribute to overall similar cell viability in counteracting 6-OHDA-induced cytotoxicity.