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Salix koreensis Anderss (Salicaceae), commonly referred to as Korean willow, is native to East Asia, particularly Korea and China, and it has been used in traditional Korean folk medicine for its potent anti-inflammatory, analgesic, and antioxidant properties. In our ongoing research efforts to discover biologically new natural products, phytochemical analysis on an ethanolic extract of S. koreensis twigs yielded the isolation and identification of ten phenolic compounds (1–10), including a newly discovered phenolic glycoside (1) named isograndidentatin D, isolated via HPLC purification. The structure of compound 1 was determined through extensive 1D and 2D NMR spectral data analysis and high-resolution electrospray ionization mass spectrometry (HR-ESIMS). Its absolute configuration was established using DP4+ probability analysis combined with gauge-including atomic orbital NMR chemical shift calculations and chemical reaction methods. The other known compounds were identified as isograndidentatin B (2), trichocarposide (3), glanduloidin C (4), tremuloidin (5), 3-O-acetylsalicin (6), 2-O-acetylsalicin (7), salicin (8), salireposide (9), and coumaric acid (10), confirmed by comparing their NMR spectra with previously reported data and further verified through liquid chromatography/mass spectrometry (LC/MS) analysis. The isolated compounds 1–10 were tested for their anti-Helicobacter pylori activities. Among these, compounds 4 and 5 demonstrated moderate anti-H. pylori activity at a concentration of 100 μM. Specifically, compound 5 showed an inhibitory activity of 35.9 ± 5.4%, making it slightly more potent than compound 4, with 34.0 ± 1.0% inhibition. These results were comparable to that of quercetin, a known anti-H. pylori agent used as a positive control in this study, which showed 38.4 ± 2.3% inhibition. The remaining compounds exhibited very weak inhibitory effects. This study highlights the potential of S. koreensis twigs as a valuable natural source of bioactive compounds for therapeutic applications against H. pylori.

Codonopsis lanceolata, commonly known as the bonnet bellflower or deodeok, is primarily found in Eastern Asia. Its roots have been used traditionally across Asia to treat various ailments such as bronchitis, coughs, asthma, and inflammation. In our ongoing efforts to discover bioactive natural products, a phytochemical investigation of the n-BuOH fraction of C. lanceolata root extracts led to the isolation and identification of a new indole alkaloid N-glycoside, deodeokaloid (D-indole-3-lactic acid N-β-D-glucopyranoside) (1), alongside known compounds tangshenoside I (2), tangshenoside IV (3), and chlorogenic acid (4) through HPLC purification. The structure of the new compound 1 was elucidated using 1D and 2D NMR spectroscopy and high-resolution electrospray ionization mass spectrometry (HR-ESIMS). Its absolute configuration was determined through a combination of DP4+ probability analysis and chemical reactions. The isolated compounds 1–4 were evaluated for their anti-Helicobacter pylori and antioxidant activities. In the anti-H. pylori assay, compound 3 showed antibacterial activity similar to that of quercetin as the positive control, inhibiting the bacterial growth by 36.8%. Compound 4 exhibited the most potent antioxidant activity, with an ABTS [2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate)] radical scavenging activity of 1624.7 mmol TE/mol and a DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging capacity of 707.5 mmol Trolox equivalent (TE)/mol. Compounds 2–4 displayed significant intracellular reactive oxygen species (ROS) scavenging capacity in lipopolysaccharide-stimulated RAW 264.7 macrophage cells. This study highlights C. lanceolata roots as a promising natural source of bioactive compounds with potential therapeutic applications.

While emission and stability of metal–halide perovskites can be enhanced through heterostructural encapsulation, a controlled synthesis route to such structures is not trivial to realize. Here, the authors design a mechanochemistry-driven protocol for synthesizing highly luminescent CsPbBr3/Cs4PbBr6 heterostructures.

The design of organic-peptide hybrids has the potential to combine our vast knowledge of protein design with small molecule engineering to create hybrid structures with complex functions. Here, we describe the computational design of a photoswitchable Ca2+-binding organic-peptide hybrid. The designed molecule, designated Ca2+-binding switch (CaBS), combines an EF-hand motif from classical Ca2+-binding proteins such as calmodulin with a photoswitchable group that can be reversibly isomerized between a spiropyran (SP) and merocyanine (MC) state in response to different wavelengths of light. The MC/SP group acts both as a photoswitch as well as an optical sensor of Ca2+ binding. Photoconversion of the SP to the corresponding MC unmasks an acidic phenol, which CaBS uses as an integral part of both its Ca2+-binding site as well as its tertiary and quaternary structure. By design, the SP state of CaBS is monomeric, while the Ca2+-bound form of the MC state is an obligate dimer, with two Ca2+-binding sites formed at the interface of a domain-swapped dimer. Thus, light and Ca2+ were expected to serve as an "AND gate" that powers a change in backbone structure/dynamics, oligomerization state, and fluorescence properties of the designed molecule. CaBS was designed using Rosetta and molecular dynamics simulations, and experimentally characterized by nuclear magnetic resonance, isothermal titration calorimetry, and optical titrations. These data illustrate the potential of combining small molecule engineering with de novo protein design to develop sensors whose conformation, association state, and optical properties respond to multiple environmental cues. [ABSTRACT FROM AUTHOR]

Salix chaenomeloides Kimura, commonly known as pussy willow, is a deciduous shrub and tree belonging to the Salicaceae family. The genus Salix spp. has been known as a healing herb for the treatment of fever, inflammation, and pain relief. The current study aimed to investigate the potential bioactive natural products from S. chaenomeloides leaves and evaluate their antibacterial activity against Helicobacter pylori. A phytochemical investigation of the ethanol (EtOH) extract of S. chaenomeloides leaves led to the isolation of 13 phenolic compounds (1–13) from the ethyl acetate (EtOAc) fraction, which showed antibacterial activity against H. pylori strain 51. The chemical structure of a new phenolic glycoside, chaenomelin (1), was established by a detailed analysis of 1D and 2D (1H-1H correlation spectroscopy (COSY), heteronuclear single-quantum coherence (HSQC), and heteronuclear multiple-bond correlation (HMBC)) nuclear magnetic resonance (NMR), high-resolution electrospray ionization mass spectroscopy (HR-ESIMS), and chemical reactions. The other known compounds were identified as 5-O-trans-p-coumaroyl quinic acid methyl ester (2), tremulacin (3), citrusin C (4), benzyl 3-O-β-d-glucopyranosyl-7-hydroxybenzoate (5), tremuloidin (6), 1-[O-β-d-glucopyranosyl(1→2)-β-d-glucopyranosyl]oxy-2-phenol (7), arbutin cinnamate (8), tremulacinol (9), catechol (10), 4-hydroxybenzaldehyde (11), kaempferol 3-rutinoside (12), and narcissin (13), based on the comparison of their NMR spectra with the reported data and liquid chromatography/mass spectrometry (LC/MS) analysis. The isolated compounds were evaluated for antibacterial activity against H. pylori strain 51. Among the isolates, 1-[O-β-d-glucopyranosyl(1→2)-β-d-glucopyranosyl]oxy-2-phenol (7) and arbutin cinnamate (8) exhibited antibacterial activity against H. pylori strain 51, with inhibitions of 31.4% and 33.9%, respectively, at a final concentration of 100 μM. These results were comparable to that of quercetin (38.4% inhibition), which served as a positive control. Generally, these findings highlight the potential of the active compounds 7 and 8 as antibacterial agents against H. pylori.

Jatropha podagrica holds a longstanding place in traditional herbal medicine, primarily utilized for addressing skin infections, acting as antipyretics, diuretics, and purgatives. In this study, our primary objective was to investigate the secondary metabolites present in J. podagrica leaves, with the aim of pinpointing natural compounds exhibiting potential antiviral activities. Five secondary metabolites (1–5), including an auronol glycoside (1), two coumarins (2 and 3), a chromane (4) and a gallotannin (5), were isolated from J. podagrica leaves. Compound 1 presented as an amalgamation of unseparated mixtures, yet its intricate composition was adroitly unraveled through the strategic deployment of a chiral HPLC column. This tactic yielded the isolation of epimers (+)-1 and (−)-1, ascertained as unreported auronol glycosides. The structures of these novel compounds, (+)-1 and (−)-1, were elucidated to be (2S)-hovetrichoside C [(+)-1] and (2R)-hovetrichoside C [(−)-1] through NMR data and HR-ESIMS analyses, enzymatic hydrolysis, and comparison of optical rotation values. Cytotoxicity and antiviral effects were assessed for the isolated compounds ((+)-1, (−)-1 and 2–5), along with compound 1a (the aglycone of 1), in the A549 human alveolar basal epithelial cell line. Each compound demonstrated a cell viability of approximately 80% or higher, confirming their non-toxic nature. In the group of compounds, compounds 3–5 demonstrated antiviral effects based on RT-qPCR results, with individual enhancements ranging from approximately 28 to 38%. Remarkably, compound 4 exhibited the most substantial antiviral effect. Utilization of compound 4 to assess immune boosting and anti-inflammatory effects revealed increased levels of STING, RIG-I, NLRP3, and IL-10 along with a decrease in TNF-α and IL-6. Therefore, these findings underscore the potential of these active compounds 3–5 not only as therapeutic agents for SARS-CoV-2 but also as new contenders for upcoming pandemics.

Rechargeable calcium batteries are promising multivalent battery systems but the lack of suitable electrodes hampers their development. Here the authors report a cathode derived from polyanion framework that demonstrates uncommonly stable and fast intercalation behaviours of calcium ions.

As part of ongoing systematic research into the discovery of bioactive secondary metabolites with novel structures from Korean wild mushrooms, we investigated secondary metabolites from a poisonous mushroom, Omphalotus japonicus (Kawam.) Kirchm. & O. K. Mill. belonging to the family Marasmiaceae, which causes nausea and vomiting after consumption. The methanolic extract of O. japonicus fruiting bodies was subjected to the fractionation by solvent partition, and the CH2Cl2 fraction was analyzed for the isolation of bioactive compounds, aided by an untargeted liquid chromatography mass spectrometry (LC–MS)-based analysis. Through chemical analysis, five fatty acid derivatives (1–5), including two new fatty acid derivatives, omphalotols A and B (1 and 2), were isolated from the CH2Cl2 fraction, and the chemical structures of the new compounds were determined using 1D and 2D nuclear magnetic resonance (NMR) spectroscopy and high resolution electrospray ionization mass spectrometry (HR-ESIMS), as well as fragmentation patterns in MS/MS data and chemical reactions followed by the application of Snatzke’s method and competing enantioselective acylation (CEA). In the anti-Helicobacter pylori activity test, compound 1 showed moderate antibacterial activity against H. pylori strain 51 with 27.4% inhibition, comparable to that of quercetin as a positive control. Specifically, compound 3 exhibited the most significant antibacterial activity against H. pylori strain 51, with MIC50 and MIC90 values of 9 and 20 μM, respectively, which is stronger inhibitory activity than that of another positive control, metronidazole (MIC50 = 17 μM and MIC90 = 46 μM). These findings suggested the experimental evidence that the compound 3, an α,β-unsaturated ketone derivative, could be used as a moiety in the development of novel antibiotics against H. pylori.

Morchella esculenta (Morchellaceae), one of the most widely appreciated wild edible mushrooms, has demonstrated antitumor activity both in vivo and in vitro. However, the molecular basis underlying its antitumor activity has not yet been elucidated. In this study, we examined the biological effects of the MeOH extract of M. esculenta fruiting bodies on four human lung adenocarcinoma cell lines. Bioactivity-guided fractionation of the MeOH extract followed by chemical investigation of its most cytotoxic hexane-soluble fraction led to the isolation of eight compounds (1 −8), including three fatty acids and five sterols. This is the first report of the isolation of compounds 1 and 3–7 from M. esculenta. Among the eight isolated compounds tested, compounds 1, 3, and 5 exhibited the most potent cytotoxicity to human lung cancer cell lines, with IC50 values ranging from 156.9 to 278 M; this activity was mediated by induction of apoptosis.

Hepoxilins (HXs) and trioxilins (TrXs) are lipid metabolites with roles in inflammation and insulin secretion. Here, the authors discover a prokaryotic source of HXs and TrXs, identify the biosynthetic enzymes and heterologously express HXs and TrXs in E. coli.

Betula platyphylla var. japonica (Betulaceae) has been used traditionally in Asian countries for the treatment of inflammatory diseases. A recent study has reported a phenolic compound, platyphylloside from B. platyphylla, that shows inhibition on adipocyte differentiation and induces lipolysis in 3T3-L1 cells. Based on this finding, we conducted phytochemical analysis of the EtOH extract of the bark of B. platyphylla var. japonica, which resulted in the isolation of phenolic glycosides (1–4). Treatment of the isolated compounds (1–4) during adipocyte differentiation of 3T3-L1 mouse adipocytes resulted in dose-dependent inhibition of adipogenesis. In mature adipocytes, arylbutanoid glycosides (2–4) induced lipolysis related genes HSL and ATGL, whereas catechin glycoside (1) had no effect. Additionally, arylbutanoid glycosides (2–4) also induced GLUT4 and adiponectin mRNA expression, indicating improvement in insulin signaling. This suggests that the isolates from B. platyphylla var. japonica exert benefial effects in regulation of adipocyte differentiation as well as adipocyte metabolism.

Armillariella tabescens (Scop.) Sing., a mushroom of the family Tricholomataceae, has been used in traditional oriental medicine to treat cholecystitis, improve bile secretion, and regulate bile-duct pressure. The present study evaluated the estrogen-like effects of A. tabescens using a cell-proliferation assay in an estrogen-receptor-positive breast cancer cell line (MCF-7). We found that the methanol extract of A. tabescens fruiting bodies promoted cell proliferation in MCF-7 cells. Using bioassay-guided fractionation of the methanol extract and chemical investigation, we isolated and identified four steroids and four fatty acids from the active fraction. All eight compounds were evaluated by E-screen assay for their estrogen-like effects in MCF-7 cells. Among the tested isolates, only (3β,5α,22E)-ergost-22-en-3-ol promoted cell proliferation in MCF-7 cells; this effect was mitigated by the ER antagonist, ICI 182,780. The mechanism underlying the estrogen-like effect of (3β,5α,22E)-ergost-22-en-3-ol was evaluated using Western blot analysis to detect the expression of extracellular signal-regulated kinase (ERK), phosphatidylinositol 3-kinase (PI3K), Akt, and estrogen receptor α (ERα). We found that (3β,5α,22E)-ergost-22-en-3-ol induced an increase in phosphorylation of ERK, PI3K, Akt, and ERα. Together, these experimental results suggest that (3β,5α,22E)-ergost-22-en-3-ol is responsible for the estrogen-like effects of A. tabescens and may potentially aid control of estrogenic activity in menopause.

Two-dimensional quantitative nuclear magnetic resonance (2D qNMR)-based metabolomics was performed to understand characteristic metabolic profiles in different aging regimes (crust from dry-aged beef, inner edible flesh of dry-aged beef, and wet-aged beef striploin) over 4 weeks. Samples were extracted using 0.6 M perchlorate to acquire polar metabolites. Partial least squares-discriminant analysis showed a good cumulative explained variation (R2 = 0.967) and predictive ability (Q2 = 0.935). Metabolites of crust and aged beef (dry- and wet-aged beef) were separated in the first week and showed a completely different aspect in the second week via NMR-based multivariable analyses. Moreover, NMR-based multivariable analyses could be used to distinguish the method, degree, and doneness of beef aging. Among them, the crust showed more unique metabolic changes that accelerated proteolysis (total free amino acids and biogenic amines) and inosine 5′-monophosphate depletion than dry-aged beef and generated specific microbial catabolites (3-indoxyl sulfate) and γ-aminobutyric acid (GABA), while asparagine, glutamine, tryptophan, and glucose in the crust were maintained or decreased. Compared to the crust, dry-aged beef showed similar patterns of biogenic amines, as well as bioactive compounds and GABA, without a decrease in free amino acids and glucose. Based on these results, the crust allows the inner dry-aged beef to be aged similarly to wet-aged beef without microbial effects. Thus, 2D qNMR-based metabolomic techniques could provide complementary information about biochemical factors for beef aging.

Carthamus tinctorius L. (Compositae; safflower or Hong Hua) has been used in Korean traditional medicine for maintaining the homeostasis of body circulation. Phytochemical investigation was performed on the florets of C. tinctorius by liquid chromatography–mass spectrometry (LC/MS), which afforded two dihydrophaseic acid glucosides (1 and 2). Isolated compounds were structurally confirmed using a combination of spectroscopic methods including 1D and 2D nuclear magnetic resonance and high-resolution electrospray ionization mass spectroscopy. Their absolute configurations were established by quantum chemical electronic circular dichroism calculations and enzymatic hydrolysis. The anti-adipogenesis activity of the isolated compounds was evaluated using 3T3-L1 preadipocytes. Treatment with the dihydrophaseic acid glucoside (1) during adipocyte differentiation prevented the accumulation of lipid droplets and reduced the expression of adipogenic genes, Fabp4 and Adipsin. However, compound 2 did not affect adipogenesis. Our study yielded a dihydrophaseic acid glucoside derived from C. tinctorius, which has potential advantages for treating obesity.

The global incidence of breast cancer has increased. However, there are many impediments to the development of safe and effective anticancer drugs. The aim of the present study was to evaluate the effect of aviculin isolated from Lespedeza cuneata (Dum. Cours.) G. Don. (Fabaceae) on MCF-7 human breast cancer cells and determine the underlying mechanism. Using the bioassay-guided isolation by water soluble tetrazolium salt (WST-1)-based Ez-Cytox assay, nine compounds (four lignan glycosides (1–4), three flavonoid glycosides (5–7), and two phenolic compounds (8 and 9)) were isolated from the ethyl acetate (EA) fraction of the L. cuneata methanolic extract. Of these, aviculin (2), a lignan glycoside, was the only compound that reduced metabolic activity on MCF-7 cells below 50% (IC50: 75.47 ± 2.23 μM). The underlying mechanism was analyzed using the annexin V Alexa Fluor 488 binding assay and Western blotting. Aviculin (2) was found to induce apoptotic cell death through the intrinsic apoptosis pathway, as indicated by the increased expression of initiator caspase-9, executioner caspase-7, and poly (ADP-ribose) polymerase (PARP). Aviculin (2)-induced apoptotic cell death was accompanied by an increase in the Bax/Bcl-2 ratio. These findings demonstrated that aviculin (2) could induce breast cancer cell apoptosis through the intrinsic apoptosis pathway, and it can therefore be considered an excellent candidate for herbal treatment of breast cancer.

Withania somnifera (L.) Dunal (Solanaceae), known as Indian ginseng or ashwagandha, has been used in Indian Ayurveda for the treatment of a variety of disorders, such as diabetes and reproductive and nervous system disorders. It is particularly used as a general health tonic, analgesic, and sedative. As part of continuing projects to discover unique bioactive natural products from medicinal plants, phytochemical investigation of the roots of W. somnifera combined with a liquid chromatography−mass spectrometry (LC/MS)-based analysis has led to the isolation of two novel phenylpropanoid esters, Withaninsams A (1) and B (2), as an inseparable mixture, along with three known phenolic compounds (3, 4, and 6) and a pyrazole alkaloid (5). The structures of the new compounds were elucidated using a combination of spectroscopic methods, including one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) and high-resolution electrospray ionization mass spectroscopy (HR-ESIMS). Withaninsams A (1) and B (2) are phenylpropanoid esters that contain a side chain, 4-methyl-1,4-pentanediol unit. To the best of our knowledge, the present study is the first to report on phenylpropanoid esters with 4-methyl-1,4-pentanediol unit. The anti-inflammatory activity of the isolated compounds (1−6) was evaluated by determining their inhibitory effects on nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages, where compound 3 inhibited LPS-induced NO production (IC50 = 33.3 μM) and TNF-α production, a pro-inflammatory cytokine (IC50 = 40.9 μM). The anti-inflammatory mechanism through the inhibition of transcriptional iNOS protein expression was confirmed by western blotting experiments for the active compound 3, which showed decreased iNOS protein expression.

Five hybrid polyketides (1a, 1b, and 2−4) containing tetramic acid core including a new hybrid polyketide, cladosin L (1), were isolated from the marine fungus Cladosporium sphaerospermum SW67, which was isolated from the marine hydroid polyp of Hydractinia echinata. The hybrid polyketides were isolated as a pair of interconverting geometric isomers. The structure of 1 was determined based on 1D and 2D NMR spectroscopic and HR-ESIMS analyses. Its absolute configuration was established by quantum chemical electronic circular dichroism (ECD) calculations and modified Mosher’s method. Tetramic acid-containing compounds are reported to be derived from a hybrid PKS-NRPS, which was also proved by analyzing our 13C-labeling data. We investigated whether compounds 1−4 could prevent cell damage induced by cisplatin, a platinum-based anticancer drug, in LLC-PK1 cells. Co-treatment with 2 and 3 ameliorated the damage of LLC-PK1 cells induced by 25 μM of cisplatin. In particular, the effect of compound 2 at 100 μM (cell viability, 90.68 ± 0.81%) was similar to the recovered cell viability of 88.23 ± 0.25% with 500 μM N-acetylcysteine (NAC), a positive control.