Natural Product Research最新文献

Antibiotic-resistant bacteria are continuously increasing the prevalent level of bacterial infection, making it a serious public health threat. In the search for solutions, natural products have emerged as promising allies that could enhance the efficacy of conventional antibiotics. This study examined the antibacterial interactions between the leaf extracts of Aristotelia chilensis (Mol.) Stuntz (maqui) and the antibiotics ampicillin and chloramphenicol using a checkerboard assay; the test were conducted against the pathogenic bacteria Escherichia coli, Staphylococcus aureus, and Salmonella typhi. The minimum inhibitory concentrations (MIC) of maqui leaf extract were 12.5, 0.04, and 1.56 mg/mL against E. coli, S. aureus, and S. typhi, respectively. Combining the extract with ampicillin or chloramphenicol, the extract reduced the MICs of the antibiotics by up to six-fold. The interaction of maqui leaf extracts with conventional antibiotics was found to significantly enhance antibacterial activity, reducing required antibiotic doses and highlighting their relevance in combating antimicrobial resistance.

In the present study, we aimed to report the identified chemical composition of methanol and n-butanol extracts obtained from the aerial parts of the Algerian Pardoglossum cheirifolium (L.) Barbier & Mathez. Heliosupine N-oxide (1) was isolated from the n-butanol extract and structurally characterised by extensive NMR and ESI-MS/MS data. LC-DAD-ESI/MS analysis on methanol extract aimed at determining pyrrolizidine alkaloids of which the Pardoglossum genus is a rich source, led to the proposed identification of lycopsamine N-oxide (2), echinatine N-oxide (3), dihydrolycopsamine (4), dihydroechinatine (5), 7-acetyl dihydrolycopsamine (6), 7-acetyllycopsamine N-oxide (7), 3'-acetylviridiflorine (8), vulgarine (10), and heliosupine (16). The glycosylated flavonols quercetin 3-O-rhamnopyranoside-(1→2)-glucopyranosyl-(1→6)-rhamnopyranoside (9), kaempferol 3-O-L-rhamnopyranosyl-(1→2)-rhamnopyranosyl-(1→6)-glucopyranoside (11), rutin (12), kaempferol 3-O-rutinoside (13), in addition to 3,4,5-trihydroxycinnamic acid glucopyranoside (14) and 3,5-dihydroxycinnamic acid-O-diglucopyranoside (15), were also identified. For the first time, we report the known metabolites 2 - 11 and 13 - 15 in the studied plant, both reported as Pardoglossum cheirifolium and Cynoglossum cheirifolium.

This work investigated the efficacy of rosemary essential oil (REO) and Boswellia serrata extracts (BSE) against Anisakis larvae for possible industrial applications. In-vitro assays exposed Anisakis type I larvae to various media containing REO (1-5%) or BSE (1-5%) with spermidine and ferulic acid at different temperatures and times. Ex-vivo trials in experimentally infested anchovy fillets were carried out only for REO. REO demonstrated significant anisakicidal activity, achieving the fastest efficacy in oil (15h at 4 °C with 5% REO). Lower concentrations (1%) showed limited effectiveness. BSE achieved a maximum 92% larval devitalisation at 5%. Ex-vivo experiments revealed initial devitalisation after 72h, reaching 100% by 168h in anchovy fillets with 5% REO-oil at 20 °C. REO exhibited substantial anisakicidal effects in marinated anchovies under refrigeration and lipid conditions. These findings highlight REO as a promising natural additive for enhancing marinated fish product safety, offering an alternative or complement to freezing for Anisakis risk management.

In the past few decades, there has been a growing interest in fish oils because of their significant health benefits. Marine Polynemus paradiseus fish locally named as topse fish are indigenous source which thrives in West Bengal's marine areas, India. Furthermore, there is a limitation of current study on P. paradiseus FO. The present study aimed to investigate P. paradiseus FO's chemical index and antibacterial effectiveness against the pathogenic microorganisms. The quality indexes of oil were conformed to Codex Alimentarius Standard. The broth microdilution method was used to assess the antibacterial properties of P. paradiseus FO and its interaction with antibiotics. Inhibition zones and MIC value of P. paradiseus FO against bacterial strains ranged from 13 to 18 mm and from 15 to 55 μg/mL, respectively. Our findings indicated P. paradiseus FO may be regarded as a viable antibacterial agent for enhancing food safety through the management of foodborne infections.

From the culture of the Antarctic psychrophilic fungus Cadophora malorum, a partially acetylated 3,5-dihydroxydecanoic acid dimer (1) was isolated and identified. The absolute configuration of the stereogenic centres of the 3,5-dihydroxydecanoic acid moiety was chemically determined through the formation of a dioxane derivative of the methyl ester. Compound 1 displayed very good antifungal activity against several phytopathogenic fungi, with MIC values between 6.25 and 25 µg/mL. A lipidomics approach was carried out to assess the effect of compound 1 on a culture of a phytopathogenic strain of Fusarium solani, which led to an increase of diglycerides in the extract of the mycelium.

Salvia veneris Hedge (Krythean sage), an endemic species of Cyprus, was investigated for its phenolic compounds and wound healing through the development of an ointment. Phenolic constituents of S. veneris ethanol extract (SVEE) were characterised by LC-MS/MS, and total phenolic content was determined using the Folin-Ciocalteu method. Twenty-two phenolic compounds were identified, with caffeic acid as the major compound and a total phenolic content of 144.6 mg GAE/g. SVEE enhanced fibroblast proliferation in the MTT assay (IC₅₀ = 56.01 ± 1.34 μg/mL) while exhibiting low cytotoxicity. In vivo evaluation of SVEE-based ointment using an excision wound model demonstrated significant, dose-dependent healing activity, with increased re-epithelialization and accelerated wound contraction (91.17 ± 1.84% by day 15) compared with control groups. These findings indicate that the rich phenolic composition of S. veneris contributes to its potent wound-healing activity, supporting the potential of SVEE-based formulations as promising natural therapeutics for wound healing.

A new tirucallane-type triterpenoid, didychaudianin A (1), along with two known tirucallane analogs (2 and 3), was isolated from the stem bark of D. gaudichaudianus (Meliaceae) growing in West Java, Indonesia. Their structures, including absolute configurations, were elucidated using HRESIMS, extensive 1D and 2D NMR spectroscopic analysis, ECD spectroscopy, and quantum chemical calculations based on density functional theory (DFT), supported by DP4+ statistical analysis. Cytotoxic evaluation against human cervical cancer HeLa cells revealed that 2 exhibited moderate activity, with an IC₅₀ value of 44.4 μM. Structure-activity relationship (SAR) analysis indicated that the stereochemistry at C-21 and the presence of a tetrahydrofuran ring in the side chain play a crucial role in modulating biological activity. The isolation of tirucallane-type triterpenoids (1-3) further enriches the chemical diversity of this compound class within the Didymocheton genus.

Viburnum cylindricum Buch. -Ham. ex D. Don is abundant in bioactive secondary metabolites with promising functions such as anti-inflammation and anti-diabetes. In this work, the polyphenolic extract of V. cylindricum leaves (VCLP) exhibited significant inhibition on α-glucosidase and urease activity. Two previously undescribed phenolic glycosides (1, 2) and fourteen known analogues (3-16) were isolated from VCLP, which were determined by spectroscopic analyses and chemical methods. The bioactivity assessment revealed that compounds 3, 4, 8, 14, and 16 could potently inhibit α-glucosidase activity with IC₅₀ values ranging from 20.83 to 28.52 μM compared to acarbose (IC₅₀ = 29.71 μM) (p < 0.05). In addition, compounds 3 and 4 showed significant urease inhibition with IC₅₀ values of 10.73 and 7.61 μM, respectively, comparable to thiourea (IC₅₀ = 28.57 μM) (p < 0.05). Moreover, the molecular docking analysis elucidated the binding mechanisms between these bioactive compounds and the enzymes α-glucosidase and urease.

This study aims to explore the therapeutic mechanisms of baicalein, a flavonoid from Wudang Mountain Scutellaria baicalensis Georgi., in treating atopic dermatitis (AD) using a combination of network pharmacology, transcriptomics, molecular docking, and in vitro experiments. Based on the UPLC-MS/MS analysis, 271 compounds including 10 categories were identified, with flavonoids (62.36%) being the most abundant. Network pharmacology revealed 21 intersection targets between baicalein and AD, and PPI network analysis identified 10 hub genes, including MMP9, MAPK3, EGFR, TLR4, etc. Skin RNA-sequencing from normal and AD mice confirmed 9 of the 21 common targets, and KEGG enrichment analysis highlighted HIF-1α signalling pathway as the key mechanism. In silico molecular docking proved that baicalein has strong binding affinity with TLR4, EGFR, and VEGFA, which were the core targets enriched in HIF-1α signalling pathway. Additionally, in vitro cell experiments demonstrated that baicalein significantly down-regulated the protein expression levels of HIF-1α, TLR4, VEGFA.

This study investigates the chemical composition and cytotoxicity potential of Calophyllum fraseri M.R.Hend. & Wyatt-Sm essential oil, complemented by molecular docking analysis. Gas chromatography-flame ionisation detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS) identified 15 components, representing 93.1% of the total oil content. The major components were β-caryophyllene (19.4%), α-cubebene (18.3%), δ-cadinene (14.0%), α-humulene (10.3%), and γ-muurolene (9.5%). The essential oil exhibited weak cytotoxic activity against HepG2, MCF-7, and A549 cancer cell lines, with IC₅₀ values of 93.4 ± 0.15 μg/mL (HepG2), 89.2 ± 0.11 μg/mL (MCF-7), and 96.3 ± 0.12 μg/mL (A549). Molecular docking results revealed favourable interactions between γ-muurolene and Akt1, α-humulene and oestrogen receptor α (ERα), and α-cubebene and the epidermal growth factor receptor tyrosine kinase (EGFR-TK) domain. These docking results provide supportive molecular insights into potential target interactions of individual constituents rather than direct predictors of the biological activity of the crude essential oil.