Search Results (115)

A comprehensive metabolic profiling of Catharanthus roseus (L.) G. Don was performed using tandem mass spectrometry, along with an evaluation of the biological activities of its various solvent extracts. Among these, the methanolic leaf extract exhibited mild radical scavenging activity, low to moderate antimicrobial activity, and limited cytotoxicity in both the brine shrimp lethality assay and MTT assay against HeLa and A549 cell lines. High-performance liquid chromatography–electrospray ionization–high-resolution tandem mass spectrometry (HPLC-ESI-HRMS/MS) analysis led to the annotation of 34 metabolites, primarily alkaloids. These included 23 indole alkaloids, two fatty acids, two pentacyclic triterpenoids, one amino acid, four porphyrin derivatives, one glyceride, and one chlorin derivative. Notably, two metabolites—2,3-dihydroxypropyl 9,12,15-octadecatrienoate and (10S)-hydroxypheophorbide A—were identified for the first time in C. roseus. Furthermore, Global Natural Products Social Molecular Networking (GNPS) analysis revealed 18 additional metabolites, including epoxypheophorbide A, 11,12-dehydroursolic acid lactone, and 20-isocatharanthine. These findings highlight the diverse secondary metabolite profile of C. roseus and support its potential as a source of bioactive compounds for therapeutic development. Full article

During the course of genome mining initiatives, we identified a marine-derived Micromonospora, assigned here as strain WMMD956; the genome of WMMD956 appeared to contain a number of features associated with everninomicins, well-known antimicrobial orthosomycins. In addition, LCMS-based hierarchical clustering analysis and principal component analysis (hcapca) revealed that WMMD956 displayed an extreme degree of metabolomic and genomic novelty. Dereplication of high-resolution tandem mass spectrometry (HRMS/MS) and Global Natural Product Social molecular networking platform (GNPS) analysis of WMMD956 resulted in the identification of several analogs of the previously known everninomicin. Chemical structures were unambiguously confirmed by HR-ESI-MS, 1D and 2D NMR experiments, and the use of MS/MS data. The isolated metabolites, 1–3, were evaluated for their antibacterial activity against methicillin-resistant Staphalococcus aureus (MRSA). Full article

Background: Endophytic fungi are prolific sources of bioactive metabolites with potential in pharmaceutical and biotechnological applications. Methods: Here, the endophytic fungus, Alternaria alstroemeriae S6, was isolated from Veronica acinifolia (speedwell), and conducted its anti-microbial activities, whole-genome sequencing and metabolome analysis. Results: The ethyl acetate extract of this fungus exhibited strong anti-bacterial activity and the inhibition zones, induced by the fungal extract at 20 mg/mL, reached 16.25 ± 0.5 mm and 26.5 ± 0.5 mm against Gram-positive and Gram-negative bacteria. To unravel the biosynthetic potential for anti-bacterial compounds, whole-genome sequencing was conducted on A. alstroemeriae S6, resulting in a high-quality assembly of 42.93 Mb encoding 13,885 protein-coding genes. Comprehensive functional genome annotation analyses, including gene ontology (GO) terms, clusters of orthologous groups (COGs), Kyoto encyclopedia of genes and genomes (KEGG), carbohydrate-active enzymes (CAZymes), and antibiotics and secondary metabolites analysis shell (antiSMASH) analyses, were performed. According to the antiSMASH analysis, 58 biosynthetic gene clusters (BGCs), including 16 non-ribosomal peptide synthetases (NRPSs), 21 terpene synthases, 12 polyketide synthetases (PKSs), and 9 hybrids, were identified. In addition, succinic acid was identified as the major metabolite within the fungal extract, while 20 minor bioactive compounds were identified through LC-MS/MS-based molecular networking on a GNPS database. Conclusions: These findings support the biotechnological potential of A. alstroemeriae S6 as an alternative producer of succinic acid, as well as novel anti-bacterial agents. Full article

In this study, we combined automated annotation tools with targeted dereplication based on MS/MS fragmentation pathway studies to identify polycyclic polyprenylated acylphloroglucinols (PPAPs) in Hypericum species, using H. patulum and H. hookeranium as a case study. These species, extensively used in traditional medicine, exhibit morphological similarities that often result in misidentification. Following UHPLC-HRMS/MS analysis of plant extracts, a molecular network approach facilitated a comprehensive comparison of their chemical composition, assigning specific clusters to O-glycosylated flavonoids and PPAPs. Eight peaks, including quercitrin, isoquercitrin, procyanidins, chlorogenic acid, quercetin, and glycosylated derivatives, were annotated from the GNPS database. For PPAPs, despite the structural complexity posing challenges for automated annotation using public databases, our targeted-dereplication strategy, relying on in-house spectral data, led to the putative identification of 22 peaks for H. patulum and H. hookeranium. Key compounds such as hyperforin, hyperscabrone K, and garcinialliptone M were detected in both species, underscoring their chemical similarity. MS/MS fragmentation pathways, particularly the successive losses of isobutene and isoprenyl units, emerged as a consistent signature for PPAP detection and may be useful for selecting PPAP-enriched extracts or fractions for further phytochemical investigations. Full article

Conyza sumatrensis is a plant of the Asteraceae family widespread in the tropical and subtropical regions of all continents. The plant is applied in folk medicine to treat malaria and helminth infections as well as other diseases. In Uganda, for example, the plant is traditionally used against ectoparasites and for wound healing. In this work, we describe a comprehensive analytical approach to investigate the metabolic profile of C. sumatrensis supported by database-assisted annotation and in silico techniques. The study aimed to analyze the metabolic profile of C. sumatrensis using multiple analytical techniques due to the complexity of the plant composition. Therefore, we employed a combination of thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS), and liquid chromatography-tandem mass spectrometry (LC-MS/MS). From the GC-MS experiments, more than 40 compounds could be annotated that had not been found in C. sumatrensis before. A number of these substances are known to possess relevant bioactivities, including antibacterial properties. Indeed, ethanolic extracts demonstrated antimicrobial activity against representative strains of both Gram-positive and Gram-negative bacteria, as shown by agar diffusion and microdilution assays. Using LC-MS/MS data, a feature-based molecular network was constructed to facilitate the comparison of two extraction solvents: water and ethanol. The majority of the features were detected in both of the extracts. However, some features were only detected using one of the extraction solvents. Our work provided valuable insights into the chemical profile of C. sumatrensis and lays the foundation for future research into its medicinal properties. Full article

The serendipitous discovery of antiparasitic drugs, such as quinine and artemisinin, of plant origin reveals that searching new chemical pharmacophores from medicinal plants is valuable. The present study sought to explore the antiplasmodial, antileishmanial, and antitrypanosomal activities of Lippia adoensis extracts. Crude extracts of L. adoensis leaves and twigs, which were obtained by extraction using 70% ethanol in water, were assayed for antiplasmodial activity against P. falciparum 3D7 and Dd2 through the SYBR green I-based fluorescence assay; and for antileishmanial, antitrypanosomal, and cytotoxic effects on Leishmania donovani, Trypanosoma brucei brucei, and Vero cells, respectively, using resazurin colorimetric assays. In vitro phytochemical analysis of L. adoensis extracts was performed using standard methods. Moreover, liquid chromatography–mass spectrometry (LC-MS) feature-based detection and molecular networking flow on Global Natural Product Social (GNPS) were also used for the phytochemical screening of L. adoensis extracts. Crude extracts from L. adoensis inhibited the growth of P. falciparum (3D7 and Dd2) (IC₅₀s; (3D7): 10.00 and 97.46 μg/mL; (Dd2): 29.48 and 26.96 μg/mL), L. donovani (IC₅₀s: 22.87–10.52 μg/mL), and T. brucei brucei (IC₅₀s: 2.30–55.06 μg/mL). The extracts were found to be non-cytotoxic to Vero cells, thus yielding median cytotoxic concentrations (CC₅₀s) above 100 μg/mL. In vitro phytochemical analysis of the crude extracts revealed the presence of alkaloids, terpenoids, phenolic compounds, and carbohydrates. The LC-MS tandem molecular networking flow predicted that the extracts contained valsafungin A and bacillamidin in the first cluster, and fatty acids, ketone, and aldehyde derivatives in the second cluster. Overall, the present study demonstrated the antiparasitic effects of L. adoensis extracts, thus justifying the use of this plant in the traditional treatment of fever and malaria conditions. Nevertheless, detailed metabolomic studies and antiparasitic mechanisms of action of the extracts are expected to unveil the potential antiparasitic hit compounds. Full article

Microalgae are a promising source of bioactive compounds, particularly proteins and peptides, with potential applications in skin health and the cosmetic industry. This study investigated the antioxidant and anti-aging properties of peptide fractions derived from Spirulina platensis and Chlorella vulgaris. Both microalgae were cultivated, and their proteins were subsequently extracted, enzymatically hydrolyzed with alcalase, and fractionated through ultrafiltration. Alkaline extraction yielded 82% protein from S. platensis and 72% from C. vulgaris. Enzymatic hydrolysis predominantly yielded <3 kDa peptides, which exhibited strong antioxidant activity reaching 78% for 2,2-diphenyl-1-picrylhidrazol (DPPH), 82% for 2,2′-azinobis-3-etilbenzothiazoline-6-sulfonic acid (ABTS), and 74% for ferric reducing antioxidant power (FRAP), with IC₅₀ values as low as 23.44 µg/mL for ABTS inhibition in C. vulgaris. These peptides also significantly inhibited skin-aging enzymes, showing 84% inhibition of elastase, 90% of collagenase, and 66% of tyrosinase. Mass spectrometry and GNPS molecular networking of the <3 kDa fraction identified several di- and tri-peptides, including Lys-Val, Val-Arg, His-Ile, Lys-Leu, Ile-Leu, and Leu-Phe, Tyr-Phe, and Leu-Gly-Leu, potentially contributing to these bioactivities. These findings suggest that the enzymatic hydrolysis of S. platensis and C. vulgaris proteins provides a sustainable and natural source of bioactive peptides for antioxidant and anti-aging applications in food, pharmaceutical, and cosmetic industries. Full article

Background: Yupingfeng San (YPFS) is a classic formula for treating allergic rhinitis (AR), which is composed of Astragalus mongholicus Bunge (AST), Atractylodes macrocephala Koidz (AMR), and Saposhni-kovia divaricata (Turcz.) Schischk (SR) at a ratio of 3:1:1. However, the potential bioactive components of YPFS relevant to AR treatment are currently unknown. Methods: This study combined in vivo chemical profiling, network pharmacology, and experimental validation to identify the substances in YPFS that are active against AR. Results: Firstly, 98 compounds in YPFS were identified using high-performance liquid chromatography–quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS/MS) with the assistance of Global Natural Products Social (GNPS) molecular networking. Then, 42 prototype components and 57 metabolites were detected in the plasma, urine, and feces of mice with AR. A network pharmacological analysis based on 42 in vivo prototypical components was also conducted to screen 15 key components and 10 core targets, and 6 key components were further selected through molecular docking. Finally, the four key active components (cimifugin, wogonin, formononetin, and atractylenolide I) were revealed to be the main ingredients of YPFS through validation (in vitro and in vivo). Conclusions: This is the first systematic study of the components of YPFS in AR mice, laying the foundation for elucidating the overall material basis of this formulation. This study provides rich basic data for further pharmacological and mechanistic studies on YPFS. Full article

Background: Euryale ferox seeds (EFSs) serve both medicinal and culinary purposes. They possess high nutritional value and are rich in polysaccharides, polyphenols, glycolipids, cyclic peptides, and other beneficial components. EFSs are known for their effects in tonifying the kidneys and strengthening essence, invigorating the spleen and alleviating diarrhea, as well as removing dampness and leucorrhea. Processing can alter the chemical composition of EFSs, with different methods yielding varying effects on their chemical makeup and, consequently, their efficacy. However, to date, no studies have systematically investigated the overall chemical composition of EFSs using different processing methods. Methods: In this study, we employed liquid chromatography high-resolution mass spectrometry (LC-HRMS) to identify the compounds in EFSs by searching databases and Global Natural Products Social Molecular Networking (GNPS), and we comprehensively explored the changes in the chemical composition of EFSs resulting from various processing methods via statistical analysis. Results: A total of 438 compounds were identified from EFSs, of which 283 were identified through database searches and 155 were identified via GNPS propagation. Statistical analysis revealed 32 and 38 differential compounds in dry-fried Euryale ferox seeds (DFEFSs) and bran-fried Euryale ferox seeds (BFEFSs), respectively. Additionally, we found a significant increase in the lipid content of the fried EFSs. Conclusions: This study provides valuable data to support the quality evaluation of processed EFSs and contributes to the research on the material basis of their medicinal efficacy. Full article

Pseudopeptides are attractive agents for protease inhibition due to their structural similarities to the natural substrates of these enzymes, as well as their enhanced stability and resistance to enzymatic degradation. We report three new ketomemicin pseudopeptides (1–3) from extracts of the marine actinomycete Salinispora pacifica strain CNY-498. Their constitution and relative configuration were elucidated using NMR, mass spectrometry, and quantum chemical calculations. Using GNPS molecular networking and publicly available Salinispora LCMS datasets, five additional ketomemicin analogs (4–8) were identified with ketomemicin production detected broadly across Salinispora species. The ketomemicin biosynthetic gene cluster (ktm) is highly conserved in Salinispora, occurring in 79 of 118 public genome sequences, including eight of the nine named species. Outside Salinispora, ktm homologs were detected in various genera of the phylum Actinomycetota that might encode novel ketomemicin analogs. Ketomemicins 1–3 were tested against a panel of eleven proteases, with 2 displaying moderate inhibitory activity. This study describes the first report of ketomemicin production by Salinispora cultures, the distribution of the corresponding biosynthetic gene cluster, and the protease inhibitory activity of new ketomemicin derivatives. Full article

Endophytic fungi are increasingly being recognized for their diverse metabolites that may exhibit antimicrobial properties. In our study, we isolated seven endophytic fungal strains from Calea pinnatifida, which were identified as Hypomontagnella barbarensis, Neopestalotiopsis clavispora, Nigrospora sacchari-officinarum, Annulohypoxylon moriforme, Colletotrichum siamense, and Colletotrichum karstii (with two isolates from the same species). Furthermore, the antimicrobial activity of the extracts was assessed, revealing that the extract from Hypomontagnella barbarensis demonstrated activity against Staphylococcus aureus. Further investigation of secondary metabolites, employing UHPLC-HR-ESI-MS/MS in combination with molecular networking, facilitated annotation of the nine compounds. Of these, five were identified based on matches with the GNPS spectral library, and four were predicted based on the molecular network. Notably, from the extract of Hypomontagnella barbarensis, two pairs of diastereoisomeric acyl-tetronic acid derivatives were isolated and characterized using MS and NMR spectroscopy. This study highlights the potential of endophytic fungi as a valuable source of novel antimicrobial agents. Full article

Background/Objectives: There is an urgent need for new and improved anthelmintics that are not constrained by existing resistance pathways and that can safeguard the health and welfare of animals. Methods: An integrated platform of chemical, bioassay, and cultivation profiling applied to a library of microbes isolated from Australian livestock pasture soil was used to detect and guide the production, isolation, characterization, identification, and evaluation of new natural products with anthelmintic properties. Results: A global natural products social (GNPS) molecular network analysis of 110 Australian pasture-soil-derived microbial extracts prioritized for antiparasitic activity identified unique molecular families in the extract of Streptomyces sp. S4S-00185A06, a strain selectively active against Dirofilaria immitis microfilariae. UPLC-DAD analysis identified metabolites with unique UV-vis chromophores and unprecedented molecular formulas. A chemical investigation of Streptomyces sp. S4S-00185A06 yielded goondicones A–H (1–8) as new examples of a rare class of spiro-isoindolinones, with structures assigned on the basis of detailed spectroscopic analysis, ECD calculations, and biosynthetic considerations. Conclusions: While goondicones 1–8 exhibit little to no in vitro inhibitory activity against Gram-positive, Gram-negative, and/or fungal pathogens, human carcinoma cells, or the livestock gastrointestinal parasite Haemonchus contortus L1–L3 larvae, 5 and 6 (and, to a lesser extent, 1) inhibit the motility of heartworm Dirofilaria immitis microfilaria (IC₅₀ 10–11 μM). A structure activity relationship analysis based on the co-metabolites 1–8 suggests that (i) an 8-OH is preferable to 8–oxo moiety, (ii) 20-NMe and 3-OH moieties are essential, and (iii) C-9 epimerization exerts no discernible impact on in vitro potency. Full article

Background: Collectively, leishmaniasis and Chagas disease cause approximately 8 million cases and more than 40,000 deaths annually, mostly in tropical and subtropical regions. The current drugs used to treat these diseases have limitations and many undesirable side effects; hence, new drugs with better clinical profiles are needed. Fungal endophytes associated with plants are known to produce a wide array of bioactive secondary metabolites, including antiprotozoal compounds. In this study, we analyzed endophytic fungal isolates associated with Theobroma cacao and Coffea arabica crop plants, which yielded extracts with antitrypanosomatid activity. Methods: Crude extracts were subjected to bioassay-guided isolation by HPLC, followed by spectrometric and spectroscopic analyses via mass spectrometry (MS) and nuclear magnetic resonance (NMR), Results: Compounds 1–9 were isolated and displayed novel antitrypanosomal and antileishmanial activities ranging from 0.92 to 32 μM. Tandem liquid chromatography–mass spectrometry (LC–MS) analysis of the organic extracts from different strains via the feature-based Global Natural Products Social (GNPS) molecular networking platform allowed us to dereplicate a series of metabolites (10–23) in the extracts. Molecular docking simulations of the active compounds, using the 3-mercaptopyruvate sulfurtransferase protein from L. donovani (Ld3MST) and the cruzipain enzyme from T. cruzi as putative molecular targets, allowed us to suggest possible mechanisms for the action of these compounds. Conclusions: The isolation of these antiprotozoal compounds confirms that crop plants like coffee and cacao harbor populations of endophytes with biomedical potential that confer added value to these crops. Full article

Currently, clinically available cancer chemopreventive drug options are limited to mostly tamoxifen and its derivatives, such as raloxifene, and approved specifically for breast cancer. Thus, the availability of chemopreventive drug molecules for other types of malignant cancers would be desirable. In previous reports, the arils of Myristica fragrans (mace) have been found to exhibit cancer chemopreventive activity. Therefore, the purpose of the present study was to identify a natural product from this species with potential chemopreventive activity guided by chemoinformatic sample analysis via Global Natural Products Social (GNPS) molecular networking and molecular docking. The neolignan licarin A (1) was identified as a potential chemopreventive constituent, and subsequently submitted to several in vitro bioassays and a zebrafish toxicity evaluation. In this work, 1 afforded superior phosphoNF-κBp65 phosphorylation activity in DU-145 prostate cancer cells compared to isoliquiritigenin (2), which was used as a natural product chemopreventive control. Both 1 and 2 showed a longer-lasting reduction in cellular stress in a cell oxidative stress real-time dose–response assay than the positive control using Hepa1c1c7 mouse hepatoma cells. In addition, 1 displayed similar activities to 2, while also being less toxic to zebrafish (Danio rerio) than both this chalcone and the clinically used chemopreventive drug tamoxifen. Full article

Scrophulariae Radix (SR), the dried root of Scrophularia ningpoensis Hemsl (S. ningpoensis), has been extensively used as traditional Chinese medicine for thousands of years. However, since the mid-20th century, the traditional processing technology of S. ningpoensis has been interrupted. Therefore, ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry technology, together with a Global Natural Product Social Molecular Networking (GNPS) method, was applied to comprehensively analyze the characteristic changes and mutual transformation of chemical constituents in the differently processed roots of S. ningpoensis, as well as to scientifically elucidate the processing mechanism of differently processed SR. As a result, a total of 149 components were identified. Notably, with the help of the GNPS data platform and MS² fragment ions, the possible structures of four new compounds (47, 48, 50, and 73) were deduced in differently processed SR samples, in which 47, 48, and 50 are iridoid glycosides, and 73 is a phenylpropanoid glycoside. Five cyclopeptides (78, 86, 97, 99, and 104) derived from leucine (isoleucine) were identified in SR for the first time. The heatmaps analysis results indicated that leucine or isoleucine may be converted to cyclopeptides under the prolonged high-temperature conditions. Moreover, it is found that short-time steaming can effectively prevent the degradation of glycosides by inactivating enzymes. This study provides a new and efficient technical strategy for systematically identifying the chemical components, rapidly discovering the components, and preliminarily clarifying the processing mechanism of S. ningpoensis, as well as also providing a scientific basis for the improvement of the quality standards and field processing of S. ningpoensis. Full article