The bioactivity-guided isolation of hypoglycemic compounds from the crude methanolic root extractof C. pentandra led to the structural characterization of ten known compounds. Five of these compounds aridanin (1), corosolic acid (2), α-amyrin (3), (E)-methylsuberenol (6), and octadecanoic acid (10) were isolated from this genus for the first time, along with other known compounds: two flavonoids (quercetin (4) and kaempferol (5)), and three sterols (β-sitosterol (7), and stigmasterol (8) mixture), and β-sitosterol glucoside (9)). By using spectroscopic and spectrometric experiments, the isolated compounds were fully characterized by comparing their data with those reported in the literature. In addition, the extract was found to have potent hypoglycemic activity with IC50 of 5.62 ± 0.25 and 5.36 ± 0.24 µM, respectively, for α-glucosidase and α-amylase, while the most active fraction displayed inhibition effects with IC50 of 5.36 ± 0.24 and 5.20 ± 0.25 µM, respectively.Amongst the isolated compounds, kaempferol (5), and a mixture of β-sitosterol (7) and stigmasterol (8) were more active compared to acarbose (IC50 of 5.47 ± 0.27 µM) and quercetin (IC50 of 12.51 ± 0.13 µM) as the references. Moreover, kaempferol exhibited the strongest activity, which agrees with flavonoids biological properties. This observation was further explored by molecular docking studies, which suggested that kaempferol could bind favourably to the active sites of the target enzymes, supporting a potential competitive inhibition mechanism. This study contributed to enrich the chemistry of Ceiba plants with five known additional compounds (1, 2, 3, 6, and 10) and made Ceiba pentandra a promising source of antihypoglycemic compounds.

The Wikstroemia genus is highly regarded in traditional Asian medicine for its diverse therapeutic applications, including the treatment of inflammatory and infectious conditions. Among its members,Wikstroemia trichotoma (Thunb.) Makino remains a promising medicinal resource which is yet to be chemicallycharacterized. To ensure the chemical consistency of W. trichotoma, we developed and validated the first HPLC method for the simultaneous quantification of three major marker compounds: chlorogenic acid (1), miconioside B (2), and matteucinol 7-O-apiofuranosyl(1→6)-glucopyranoside (3). Chromatographic separation was achieved on a C18 column using a gradient elution system of 0.1% formic acid in water and 0.1% formic acid in acetonitrile. Detection was optimized using a photodiode array (PDA) detector at 280 and 325 nm, based on the absorption maxima of the markers. The method was validated in accordance with the International Council for Harmonisation (ICH) and the Ministry of Food and Drug Safety (MFDS) guidelines. The results demonstrated high linearity (r2 > 0.999), with limits of detection and quantitation ranging from 4.28–6.42 and 12.97–19.47 μg/ mL, respectively. Intra- and inter-day precision (% RSD ≤ 1.83%) and accuracy (recoveries of 92.5–101.7%) were within acceptable limits. Quantitative analysis revealed the contents of 1, 2, and 3 in the W. trichotoma extract to be 19.9, 139.8, and 264.9 mg/g, respectively. This study provides a reliable analytical framework for the standardization, quality control, and future pharmacological evaluation of W. trichotoma.

A phytochemical study of the root extract of Hemerocallis fulva var. kwanso Regel resulted in the isolation and structural characterization of four lignans (1‒4), three flavanones (5, 6, and 8), one chalcone (9), and two monoterpenes (7 and 10). Enzyme inhibition assays revealed that two flavanone glucosides (5 and 6) showed significant inhibitory effect against protein tyrosine phosphatase 1B (PTP1B), with IC50 values of 31.38 µM and 51.46 µM, respectively. Further enzyme kinetic studies demonstrated that these two compounds acted as noncompetitive PTP1B inhibitors, with Ki values of 30.88 µM and 50.38 µM, respectively.

Punica granatum L. has been widely used in traditional medicine and is known to contain bioactiveellagitannins with potential antidiabetic properties. The primary objective of this study was to develop and validate a reliable HPLC-DAD method for the quantitative analysis of major compounds isolated from stems and pericarpium of P. granatum, namely pedunculagin (1), flavogallonic acid (2), casuarinin (3), isocorilagin (4), methyl brevifolincarboxylate (5), eschweilenol C (6), ellagic acid-4-O-β-D-xylopyranoside (7), ellagic acid (8), and quercitrin (9), and to futher evaluate their α-glucosidase inhibitory activity. The analytical method demonstrated linearity with correlation coefficients (R²) exceeding 0.9991. The limits of detection (LOD) and limits of quantification (LOQ) ranged from 2.75 to 7.44 μg/mL and 8.33 to 22.54 μg/mL, respectively. Intra-day and inter-day precision showed relative standard deviation (RSD) values below 2.85% and 2.72%, while recovery values ranged from 96.87% to 107.72%, confirming the accuracy and reliability of the method.Quantitative results revealed that ellagitannins were the predominant constituents in both stems and pericarpium of P. granatum. Biological evaluation demonstrated that several isolated compounds exhibited strong αglucosidase inhibitory activity, with compounds 1–3 showing significantly stronger activity than the reference inhibitor acarbose. Enzyme kinetic studies and molecular docking analyses were conducted to clarify their inhibition mechanisms, revealing mixed, uncompetitive and competitive inhibition modes associated with binding to catalytic or allosteric sites of the enzyme. This study integrates quantitative analysis with mechanistic enzyme inhibition evaluation, providing a practical analytical tool for quality control of P. granatum and scientific evidence supporting its potential application in antidiabetic therapy.

Dystaenia takeshimana (Nakai) Kitagawa belongs to the family Apiaceae (Umbelliferae) and is a perennial herb naturally endemic to Ulleung Island, Republic of Korea. Following its successful introduction and cultivation in mainland Korea, a phytochemical investigation of this plant was carried out. As a result, thirteen compounds were isolated and structurally characterized, including one flavonoid glycoside (1), two polyacetylenes (2 and3), one caffeoylquinic acid derivative (4), one aliphatic hydroxy acid (5), four phenolic acids and their derivatives(6, 8–10), one aromatic alcohol derivative (7), two carbohydrates (11 and 12), and one phytosterol (13). The structures of these compounds were elucidated based on spectroscopic analyses and comparison with previously reported literature data. To the best of our knowledge, this study represents the first report on the isolation of falcarinol (2), trans-4-hydroxy-2-nonenoic acid (5), and sucrose (11) from D. takeshimana and the evaluation of their protein tyrosine phosphatase 1B (PTP1B) inhibitory activity. Compounds 2, 3, and 5 exhibited potent PTP1B inhibitory effects with IC50 values of 10.74, 8.31, and 25.24 µM, respectively. Enzyme kinetic studies indicated noncompetitive inhibition by 2 and mixed-type inhibition by 5 against PTP1B. Furthermore, molecular docking analysis was performed to investigate the binding interactions between the active compounds and the enzyme active site.

Phytochemical investigation of the water extract and alkaloid fraction of Areca catechu L. led to theisolation of one new methoxyflavonoid rutinoside (1), together with eleven known compounds (2−12), five of which (8−12) belong to the pyridine alkaloid class. The structure of the new compound was elucidated through extensive spectroscopic analyses, including 1D and 2D NMR experiments and high-resolution mass spectrometry.Notably, rhamnazin-3-O-rutinoside (2) is reported here for the first time from this species. The isolated compounds were evaluated for their inhibitory activity against protein tyrosine phosphatase 1B (PTP1B) using a p-nitrophenyl phosphate assay. Flavonoids (3 and 4) and stilbene (5) exhibited notable inhibitory activity, with IC50 values of 13.30 ± 0.71, 13.44 ± 0.84, and 8.68 ± 0.12 μM, respectively. In contrast, methoxyflavonoid rutinosides (1 and 2) and pyridine alkaloids (8−12) did not show significant inhibitory activity against PTP1B.These findings provide additional chemical insights into A. catechu and its constituents in relation to PTP1B inhibition.

LC-MS/MS-based molecular networking was used to guide the targeted isolation of terpenylated coumarins from the barks of Ailanthus altissima. Five known terpenylated coumarins (1–5), along with two simple coumarins (6 and 7), were isolated from the CH 2 Cl 2 -soluble fraction. Their structures were determined using spectroscopic techniques, including 1D and 2D NMR and LC-HR-MS/MS. Notably, altissimacoumarins C (1), F (3), and H (4) demonstrated potent inhibition of LPS-induced nitric oxide production in RAW 264.7 macrophages, with IC50 values of 36.1, 27.9, and 11.2 μM, respectively. These results demonstrate the antiinflammatory properties of A. altissima, supporting its possible application in treating inflammatory disorders.

A2E, a major pyridinium bisretinoid component of retinal lipofuscin, functions as a photosensitizer that undergoes blue light-induced oxidation, contributing to oxidative stress in age-related macular degeneration (AMD). This study investigated whether lipophilic antioxidants and non-antioxidant hydrophobic molecules protect A2E primarily through reactive oxygen species (ROS) quenching, modulation of its local microenvironment, or both. A2E was irradiated with blue light in the presence or absence of hydrophobic additives: palmitic acid (PA), vitamin E, β-carotene, lutein, zeaxanthin, and zeaxanthin dipalmitate (ZDP). Fluorescence spectroscopy assessed photophysical changes. A2E degradation was quantified using reverse-phase LC-MS with optimized electrospray ionization, distinguishing actual A2E loss from fluorescence artifacts. All additives significantly reduced A2E degradation, with protection strongly correlated with hydrophobicity. ZDP preserved about 76% of A2E, and even non-antioxidant PA offered marked protection. Fluorescence spectra showed compound-specific emissions and, notably, increased A2E fluorescence intensity with a blue shift, particularly with ZDP and PA, suggesting enhanced co-localization in lipid-rich domains. These results reveal two complementary protective mechanisms: classical ROS scavenging by carotenoids and vitamin E, and microenvironment remodeling by highly lipophilic molecules like ZDP and PA. The microenvironmental remodeling effects of lipophilic compounds remain speculative and warrants further investigation. Thus, strategies targeting both ROS neutralization and A2E’s hydrophobic niche may effectively mitigate blue-light-driven retinal damage in AMD.

Zelkova serrata (Thunb.) Makino is a deciduous tree commonly distributed in East Asia. Several investigations have documented the biological activity of extracts of this species, igniting increased interest in its therapeutic potential. However, the phytochemical constituents accountable for these activities remain largely unexplored. In this study, we focused on the antioxidant potential of the leaves and twigs, utilizing bioactivityguided fractionation combined with LC-QTOF-MS online DPPH screening to systematically identify the active compounds. This approach led to the isolation of eight compounds, three of which (compounds 1, 3, and 7) have not previously been documented in the genus Zelkova. Among the isolates, 4 emerged as the most potent antioxidant, exhibiting significant radical scavenging activity in both DPPH (IC 50 = 13.67 ± 1.21 μM) and ABTS (IC50 = 2.69 ± 0.48 μM) assays, exceeding ascorbic acid (IC 50 = 61.51 ± 10.22 μM) and trolox (IC50 = 8.22 ± 2.16 μM), respectively. Our findings not only enrich the phytochemical profile of Z. serrata but also highlight the effectiveness of LC-MS-DPPH as an effective approach for rapid antioxidant discovery.