Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 829
Filtrar
1.
Bioorg Chem ; 147: 107329, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38608410

RESUMO

By co-culturing two endophytic fungi (Chaetomium virescens and Xylaria grammica) collected from the medicinal and edible plant Smilax glabra Roxb. and analyzing them with MolNetEnhancer module on GNPS platform, seven undescribed chromone-derived polyketides (chaetoxylariones A-G), including three pairs of enantiomer ones (2a/2b, 4a/4b and 6a/6b) and four optical pure ones (1, 3, 5 and 7), as well as five known structural analogues (8-12), were obtained. The structures of these new compounds were characterized by NMR spectroscopy, single-crystal X-ray diffraction, 13C NMR calculation and DP4+ probability analyses, as well as the comparison of the experimental electronic circular dichroism (ECD) data. Structurally, compound 1 featured an unprecedented chromone-derived sulfonamide tailored by two isoleucine-derived δ-hydroxy-3-methylpentenoic acids via the acylamide and NO bonds, respectively; compound 2 represented the first example of enantiomeric chromone derivative bearing a unique spiro-[3.3]alkane ring system; compound 3 featured a decane alkyl side chain that formed an undescribed five-membered lactone ring between C-7' and C-10'; compound 4 contained an unexpected highly oxidized five-membered carbocyclic system featuring rare adjacent keto groups; compound 7 featured a rare methylsulfonyl moiety. In addition, compound 10 showed a significant inhibition towards SW620/AD300 cells with an IC50 value of PTX significantly decreased from 4.09 µM to 120 nM, and a further study uncovered that compound 10 could obviously reverse the MDR of SW620/AD300 cells.

2.
J Nat Prod ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557026

RESUMO

The potential of natural products as pharmaceutical and agricultural agents is based on their large structural diversity, resulting in part from modifications of the backbone structure by tailoring enzymes during biosynthesis. Flavin-dependent monooxygenases (FMOs), as one such group of enzymes, play an important role in the biosynthesis of diverse natural products, including cyclodipeptide (CDP) derivatives. The FMO PboD was shown to catalyze C-3 hydroxylation at the indole ring of cyclo-l-Trp-l-Leu in the biosynthesis of protubonines, accompanied by pyrrolidine ring formation. PboD substrate promiscuity was investigated in this study by testing its catalytic activity toward additional tryptophan-containing CDPs in vitro and biotransformation in Aspergillus nidulans transformants bearing a truncated protubonine gene cluster with pboD and two acetyltransferase genes. High acceptance of five CDPs was detected for PboD, especially of those with a second aromatic moiety. Isolation and structure elucidation of five pyrrolidine diketopiperazine products, with two new structures, proved the expected stereospecific hydroxylation and pyrrolidine ring formation. Determination of kinetic parameters revealed higher catalytic efficiency of PboD toward three CDPs consisting of aromatic amino acids than of its natural substrate cyclo-l-Trp-l-Leu. In the biotransformation experiments with the A. nidulans transformant, modest formation of hydroxylated and acetylated products was also detected.

3.
Heliyon ; 10(6): e26995, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38560683

RESUMO

There have been many research reports on the reinforcement of small-sized square columns with a cross-section of 200mm-300mm using prestressed carbon fiber-reinforced polymer (CFRP) materials, while there are few studies on piers in bridge and tower columns in cable-stayed bridges with a cross-section of several meters or even tens of meters. The horizontal prestressed steel tendons in the anchorage zone of tower columns in cable-stayed bridge replaced by prestressed CFRP sheets can not only facilitate construction and maintenance, but also have good fatigue resistance. The prestressed CFRP plate is used to reinforce the large-sized tower columns by using a specific device to tension the CFRP plate wrapped around the surface of the members. The tensioning device and test pedestal based on WSGG (wave-shaped-gear-grip) anchor clamping of CFRP plate have been developed in this paper, and the CFRP plate circumferential tensioning tests on the pedestal have been conducted. The test results are as follows: (1) the developed device can achieve circumferential tensioning of single-layer CFRP plate to 0.5ftk of the material, reaching a tensile force of 60kN, and generate effective restraint pressure on a 2-m long composite compression component; (2)The calculation formula for the constraint pressure generated by the circumferential prestressed CFRP sheet on the component has been derived and verified, and the maximum error between the calculated value and the experimental value is within 5%; (3) When iron sheet serves as the interface medium between CFRP plate and compression components, the prestress loss of the CFRP plate tensioned at one end is about 84% and 58%-60% when tensioned at both ends. It can be seen that the effective prestress of the CFRP plate with iron sheet as the interface medium is relatively small. Meanwhile, based on the distribution of compressive stress in the components and the effective pre tension value of CFRP plate, it can be seen that two end tensioning is better than one end tensioning; (4) The tensile stress of CFRP plate along the member is a cubic function when the tension force is 60kN, so it is deduced that the constrained compressive stress generated by CFRP plate on the member is a quadratic function distribution.

4.
J Psychiatr Res ; 174: 19-25, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38604111

RESUMO

This present study aimed to investigate the sex-specific association of plasma neutrophil gelatinase-associated lipocalin (NGAL) with cognition in drug-naïve schizophrenia patients for the first time. A total of 204 participants in this study, including 137 drug-naïve schizophrenia (DNS) patients and 67 healthy controls (HCs). All participants completed the Measurements and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Consensus Cognitive Battery (MCCB), and were collected fasting venous blood for NGAL measurement. DNS patients also complete the Positive and Negative Syndrome Scale (PANSS). Partial correlation analysis and multiple linear regression were used to explore sex-specific associations between NGAL and cognition. All dimensions of MCCB scores were significantly lower in both male and female DNS patients than HCs. Sex differences were significant in cognitive performance in both DNS patients and HCs. Female DNS patients experienced poorer working memory and reason& problem solving than male patients. Female HCs performed a better attention/vigilance and visual learning, a poorer reason& problem solving than male HCs. In patients with DNS, NGAL levels were negatively associated with positive subscale of PANSS and positively associated with working memory and visual learning only in female. However, there was no significant correlation between NGAL levels and all cognitive tests in both male and female HCs. Regression model showed that higher level of NGAL was an independent protective factor for cognitive performance in female patients with DNS, whereas there was no such role in male patients. Our findings suggest sex specificity between NGAL levels and cognitive performance in DNS patients.

5.
Phytochemistry ; 222: 114070, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38574957

RESUMO

Ten ergostane-type steroids, including seven undescribed ones named spectasteroids A-G, were obtained from Aspergillus spectabilis. Their structures and absolute configurations were determined based on HRESIMS, NMR, ECD calculations, and single-crystal X-ray diffraction analyses. Structurally, spectasteroid A was a unique example of aromatic ergostane-type steroid that featured a rare peroxide ring moiety; spectasteroid B contained a rare oxetane ring system formed between C-9 and C-14; and spectasteroid C was an unusual 3,4-seco-ergostane steroid with an extra lactone ring between C-3 and C-9. Spectasteroids F and G specifically showed inhibitory effects against concanavalin A-induced T lymphocyte proliferation and lipopolysaccharide-induced B lymphocyte proliferation, with IC50 values ranging from 2.33 to 4.22 µM. Spectasteroid F also showed excellent antimultidrug resistance activity, which remarkable enhanced the inhibitory activity of PTX on the colony formation of SW620/Ad300 cells.

6.
Artigo em Inglês | MEDLINE | ID: mdl-38551516

RESUMO

BACKGROUND: The effect of physical therapy on pain and disability alleviation in patients with chronic low back pain (cLBP) has been demonstrated, but the risk factors for treatment failure remain unknown. AIM: To explore the associations of baseline demographic and clinical characteristics with treatment failure after physical therapy intervention for cLBP. DESIGN: A secondary analysis of a single-blind randomized clinical trial. SETTING: A rehabilitation hospital. POPULATION: A total of 98 patients with cLBP completed the 12-month measurement. METHODS: Patients were randomly grouped into 3-month therapeutic aquatic exercise or physical therapy modalities. The primary outcome was treatment failure, which was defined as a decrease in the numeric rating scale to less than 2.0 points at 12-month follow-up. Associations between baseline demographic and clinical characteristics with risk of treatment failure were assessed by logistic regressions. RESULTS: The pain intensity in the failure cases was alleviated after 3-month intervention but continuously increased at 6- and 12-month follow-up (P<0.05). Old age was significantly associated with an increased risk of treatment failure (adjusted OR 3.26, 95% CI 1.11-9.60). Compared with those receiving physical therapy modalities, the patients receiving therapeutic aquatic exercise had less risk of treatment failure (adjusted OR 0.19, 95% CI 0.08-0.47), and age (P=0.022) was a modifier for this association. CONCLUSIONS: Compared with younger ones, older patients with cLBP had a higher risk of treatment failure after physical therapy and gained a stronger benefit of long-term pain alleviation from therapeutic aquatic exercise. CLINICAL REHABILITATION IMPACT: Therapeutic aquatic exercise is an effective therapy for cLBP and more helpful for preventing treatment failure than physical therapy modalities, especially for older patients.

7.
Cell Commun Signal ; 22(1): 195, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539203

RESUMO

BACKGROUND: Lung cancer is cancer with the highest morbidity and mortality in the world and poses a serious threat to human health. Therefore, discovering new treatments is urgently needed to improve lung cancer prognosis. Small molecule inhibitors targeting the ubiquitin-proteasome system have achieved great success, in which deubiquitinase inhibitors have broad clinical applications. The deubiquitylase OTUD3 was reported to promote lung tumorigenesis by stabilizing oncoprotein GRP78, implying that inhibition of OTUD3 may be a therapeutic strategy for lung cancer. RESULTS: In this study, we identified a small molecule inhibitor of OTUD3, Rolapitant, by computer-aided virtual screening and biological experimental verification from FDA-approved drugs library. Rolapitant inhibited the proliferation of lung cancer cells by inhibiting deubiquitinating activity of OTUD3. Quantitative proteomic profiling indicated that Rolapitant significantly upregulated the expression of death receptor 5 (DR5). Rolapitant also promoted lung cancer cell apoptosis through upregulating cell surface expression of DR5 and enhanced TRAIL-induced apoptosis. Mechanistically, Rolapitant directly targeted the OTUD3-GRP78 axis to trigger endoplasmic reticulum (ER) stress-C/EBP homologous protein (CHOP)-DR5 signaling, sensitizing lung cancer cells to TRAIL-induced apoptosis. In the vivo assays, Rolapitant suppressed the growth of lung cancer xenografts in immunocompromised mice at suitable dosages without apparent toxicity. CONCLUSION: In summary, the present study identifies Rolapitant as a novel inhibitor of deubiquitinase OTUD3 and establishes that the OTUD3-GRP78 axis is a potential therapeutic target for lung cancer.


Assuntos
Chaperona BiP do Retículo Endoplasmático , Neoplasias Pulmonares , Compostos de Espiro , Humanos , Camundongos , Animais , Linhagem Celular Tumoral , Neoplasias Pulmonares/tratamento farmacológico , Proteômica , Proteases Específicas de Ubiquitina/metabolismo , Apoptose , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia
8.
Chin J Nat Med ; 22(3): 273-279, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38553194

RESUMO

Hyparillums A (1) and B (2), two previously unidentified polycyclic polyprenylated acylphloroglucinols (PPAPs) with intricate architectures, were isolated from Hypericum patulum Thunb. Hyparillum A was the first PPAP with eight-carbon rings based on an unprecedented 6/6/5/6/6/5/6/4 octocyclic system featuring a rare heptacyclo[10.8.1.11,10.03,8.08,21.012,19.014,17]docosane core. In contrast, hyparillum B featured a novel heptacyclic architecture (6/6/5/6/6/5/5) based on a hexacyclo[9.6.1.11,9.03,7.07,18.011,16]nonadecane motif. Furthermore, hyparillums A and B demonstrated promising inhibitory effects on the proliferation of murine splenocytes stimulated by anti-CD3/anti-CD28 monoclonal antibodies and lipopolysaccharide, exhibiting half-maximal inhibitory concentration (IC50) values ranging from 6.13 ± 0.86 to 12.69 ± 1.31 µmol·L-1.


Assuntos
Hypericum , Camundongos , Animais , Estrutura Molecular , Floroglucinol/farmacologia
9.
Bioorg Chem ; 146: 107280, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38479131

RESUMO

Ten new compounds, including three pairs of diarylcyclopentenone enantiomers (±) talaromycesins A-C (1-3) and four biphenyl derivatives talaromycesins D-G (4-7), along with four known compounds (8-11), were isolated from the fungus Talaromyces adpressus. Their structures were determined by analyses of extensive NMR spectroscopic and HRESIMS data, and their absolute configurations were elucidated by the dimolybdenum tetraacetate [Mo2(AcO)4]-induced ECD spectra, X-ray crystallographic studies, and ECD calculations. These new compounds were evaluated for their immunosuppressive activities for the first time, and compound 7 probably exerted liver-protective and anti-inflammatory effects on Con A-induced AIH by decreasing the levels of inflammatory cytokines, modulating immune homeostasis, and decreasing hepatocyte apoptosis, which may become a potential drug for the treatment of autoimmune diseases.


Assuntos
Talaromyces , Espectroscopia de Ressonância Magnética , Talaromyces/química , Compostos de Bifenilo , Estrutura Molecular
10.
Sci Rep ; 14(1): 5570, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448451

RESUMO

The increasing interest in filter pruning of convolutional neural networks stems from its inherent ability to effectively compress and accelerate these networks. Currently, filter pruning is mainly divided into two schools: norm-based and relation-based. These methods aim to selectively remove the least important filters according to predefined rules. However, the limitations of these methods lie in the inadequate consideration of filter diversity and the impact of batch normalization (BN) layers on the input of the next layer, which may lead to performance degradation. To address the above limitations of norm-based and similarity-based methods, this study conducts empirical analyses to reveal their drawbacks and subsequently introduces a groundbreaking complex hybrid weighted pruning method. By evaluating the correlations and norms between individual filters, as well as the parameters of the BN layer, our method effectively identifies and prunes the most redundant filters in a robust manner, thereby avoiding significant decreases in network performance. We conducted comprehensive and direct pruning experiments on different depths of ResNet using publicly available image classification datasets, ImageNet and CIFAR-10. The results demonstrate the significant efficacy of our approach. In particular, when applied to the ResNet-50 on the ImageNet dataset, achieves a significant reduction of 53.5% in floating-point operations, with a performance loss of only 0.6%.

11.
Phytochemistry ; 221: 114044, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38452879

RESUMO

Seven undescribed compounds (1-7) along with six known compounds (8-13) were isolated from Eurotiaceae Aspergillus quadrilineatus. Their structures and absolute configurations were elucidated by NMR, HRESIMS, and ECD calculations. Quadrilisteroids A (1) and B (2) possessed an unprecedented 6/5/6/6/6/5 hexacyclic ring system in conjugation with a highly fused benzene ring, while quadrilisteroid C (3) featured a surprising 6/6/6/5/5-fused carbocyclic skeleton. Quadrilisteroid C (3) exhibited potent inhibitory activity against LPS-induced proliferation of B lymphocyte cells with an IC50 value of 1.03 µM. Compound 4, demonstrated inhibitory activity against Con A-induced proliferation of T lymphocyte cells with IC50 values of 6.42 µM.


Assuntos
Aspergillus , Fungos , Aspergillus/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular
12.
Bioorg Med Chem ; 103: 117685, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38503009

RESUMO

Genome sequencing on an intertidal zone-derived Aspergillus flavipes strain revealed its great potential to produce secondary metabolites. To activate the cryptic compounds of A. flavipes, the global regulator flLaeA was knocked out, leading to substantial up-regulation of the expression of two NRPS-like biosynthetic gene clusters in the ΔflLaeA mutant. With a scaled-up fermentation of the ΔflLaeA strain, five compounds, including two previously undescribed piperazine derivatives flavipamides A and B (1 and 2), along with three known compounds (3-5), were obtained by LC-MS guided isolation. The new compounds were elucidated by spectroscopic analysis and electronic circular dichroism (ECD) calculations, and the biosynthetic pathway was proposed on the bias of bioinformatic analysis and 13C isotope labeling evidence. This is the first report to access cryptic fungi secondary metabolites by inactivating global regulator LaeA and may provide a new approach to discovering new secondary metabolites by such genetic manipulation.


Assuntos
Aspergillus , Fungos , Aspergillus/genética , Aspergillus/metabolismo , Piperazinas/farmacologia , Piperazinas/metabolismo
13.
Phytochemistry ; 221: 114047, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38462213

RESUMO

Hyperatins A-D (1-4), four previously undescribed polycyclic polyprenylated acylphloroglucinols, were isolated from Hypericum perforatum L. (St. John's wort). Compound 1 possessed a unique octahydroindeno[1,7a-b]oxirene ring system with a rare 2,7-dioxabicyclo[2.2.1]heptane fragment. Compounds 2-4 had an uncommon decahydrospiro[furan-3,7'-indeno[7,1-bc]furan] ring system. Their structures were established by spectroscopic analyses and X-ray crystallography. Plausible biosynthetic pathways of 1-4 were also proposed. Compounds 1 and 2 exerted promising hypoglycemic activity by inhibiting glycogen synthase kinase 3 expression in liver cells.


Assuntos
Antineoplásicos , Hypericum , Hypericum/química , Cristalografia por Raios X , Fígado , Furanos , Floroglucinol/farmacologia , Floroglucinol/química , Estrutura Molecular
14.
Phytochemistry ; 221: 114065, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38521495

RESUMO

In this study, 13 previously undescribed acorane sesquiterpenoids, namely, proliferacorins A-M, were isolated from the solid fermentation of Fusarium proliferatum. Their structures and absolute configurations were confirmed via spectroscopic analyses, quantum-chemical NMR calculations with DP4+ probability analyses, ECD calculations and comparisons, and single-crystal X-ray diffraction techniques. Proliferacorins A-E (1-5) have a 7-oxa-tricyclo[6.3.1.01,5]tridecane decorated with a rare ether bridge between C-7 and C-11, while proliferacorin F (6) possesses a 7-oxa-tricyclic[6.4.0.01,5]dodecane skeleton with an unusual ether bond between C-6 and C-11. Proliferacorins C and D (3 and 4) are a pair of isomers at the carbon bridge between C-5 and C-7, whereas proliferacorins H and I (8 and 9) are a pair of spiro carbon isomers. All isolates were tested for their cytotoxic, anti-inflammatory, and immunosuppressive activities.


Assuntos
Fusarium , Sesquiterpenos , Fusarium/química , Sesquiterpenos/química , Carbono , Éteres , Estrutura Molecular
15.
Chem Biol Interact ; 392: 110927, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38403145

RESUMO

Aromatase inhibitors are commonly employed in the treatment of hormone-dependent breast cancers, and flavonoids have emerged as a promising alternative to existing drug classes with unfavorable side effects. In this study, we conducted in vitro investigations into CYP19A1 (aromatase) inhibitory potential of 14 flavonoids, including pinocembrin, sakuranetin, eriodictyol, liquiritigenin, naringenin, hesperetin, flavanone, baicalein, chrysin, nobiletin, luteolin, sinensetin, tricin, and primuletin. Flavonoids displaying inhibitory activity were further assessed using in silico tools, such as molecular docking to predict binding affinities, as well as SwissADME, admetSAR, and QED (Quantitative Estimate of Drug-likeness) for drug-likeness prediction. Flavonoids with IC50 values less than 10 µM, pinocembrin, eriodictyol, naringenin, liquirtigenin, sakuranetin, and chrysin, exhibited favorable physicochemical properties and ADME profiles, suggesting their potential for development as novel flavonoid-based aromatase inhibitors. This study would provide valuable insights for the development of flavonoid-based aromatase inhibitors for the treatment of breast cancer.


Assuntos
Inibidores da Aromatase , Neoplasias da Mama , Humanos , Feminino , Inibidores da Aromatase/farmacologia , Inibidores da Aromatase/química , Neoplasias da Mama/tratamento farmacológico , Simulação de Acoplamento Molecular , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Flavonoides/química , Aromatase
16.
Phytochemistry ; 220: 114012, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38311151

RESUMO

Penigrines A-E (1-5), five undescribed azepine-indole alkaloids, were isolated from the fungus Penicillium griseofulvum. Their structures with absolute configurations were determined by NMR, HRESIMS, ECD calculation, and X-ray diffraction experiments. Penigrine C (3) possesses an undescribed 6-oxa-8-azabicyclo[3.2.2]nonane-7,9-dione moiety that fused to an indole core, and penigrines D and E (4 and 5) are a pair of epimers. The plausible biosynthetic pathways of 1-5 are proposed. Penigrine A (1) shows the potential for heart failure treatment.


Assuntos
Alcaloides Indólicos , Penicillium , Alcaloides Indólicos/química , Penicillium/química , Espectroscopia de Ressonância Magnética , Fungos , Estrutura Molecular
17.
Org Lett ; 26(8): 1677-1682, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38363662

RESUMO

A known polycyclic tetramate macrolactam (aburatubolactam C, 3) and three new ones (aburatubolactams D-F, 4-6, respectively) were isolated from the marine-derived Streptomyces sp. SCSIO 40070. The absolute configuration of 3 was established by X-ray analysis. A combinatorial biosynthetic approach unveiled biosynthetic enzymes dictating the formation of distinct 5/5-type ring systems (such as C7-C14 cyclization by AtlB1 in 5 and C6-C13 cyclization by AtlB2 in 6) in aburatubolactams.


Assuntos
Streptomyces , Ciclização
18.
Org Lett ; 26(8): 1734-1738, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38364796

RESUMO

TlnA produces a distinct cyclohexane-fused 5-8-6 ring system, different from the prevalent 5-8-5 scaffold synthesized by well-established enzymes. This study identifies two conformations of a carbocation intermediate, revealing how the enzyme environment prohibits one conformation due to steric hindrance, thereby directing the formation of the 5-8-6 system over the 5-8-5 scaffold. This investigation enhances our understanding of diterpene biosynthesis and the impact of enzyme environments on chemical reactions, providing valuable insights into the formation of complex cyclic structures.


Assuntos
Diterpenos , Esqueleto , Conformação Molecular , Compostos Radiofarmacêuticos
19.
J Agric Food Chem ; 72(7): 3549-3559, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38325810

RESUMO

Bipoladiens A-E (1-5), five new ophiobolin-derived sesterterpenoids, and a known compound 6 (bipolaricin R) were isolated from the cultures of the phytopathogenic fungus Bipolaris maydis. Their structures and absolute configurations were elucidated based on comprehensive spectroscopic analyses, HRESIMS, electronic circular dichroism (ECD) calculations, and single-crystal X-ray diffraction analyses. Notably, compound 1 has an undescribed tetracyclic 5/8/5/7 fused carbon skeleton, and compound 2 possesses a rare multicyclic caged ring system. The biosynthetic pathway of 1 was proposed starting from 6 via a series of oxidation and cyclization reactions. Compound 6 showed excellent antiproliferation and apoptosis induction effects against A549 cell line. Additionally, compounds 5 and 6 exhibited noticeable antimicrobial ability against Bacillus cereus, Staphylococcus aureus, and Staphylococcus epidermidis. These findings not only developed the chemical and bioactivities diversities of ophiobolin-sesterterpenoid but also provided an idea to boost the application of natural products in the control of food pathogens.


Assuntos
Anti-Infecciosos , Sesterterpenos , Sesterterpenos/farmacologia , Sesterterpenos/química , Bipolaris , Estrutura Molecular
20.
J Nat Prod ; 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38372239

RESUMO

In this study, we isolated lovastatin derivatives, including aculeatiols A-G (1-7) and three known compounds (8-10), from Aspergillus aculeatus. Their structures and absolute configurations were experimentally determined by high-resolution electrospray ionization mass spectrometry, nuclear magnetic resonance spectroscopy, and X-ray diffraction analyses, and the results were corroborated by quantum-chemical calculations. As members of the lovastatin derivatives, aculeatiols A-C (1-3) possess a γ-lactone functional group in the side chain. Compound 6 represents the first example that features an undescribed aromatized heterotetracyclic 6/6/6/6 ring system. Biologically, the lipid-lowering effects of all of these compounds were evaluated by analyzing the free fatty acid-induced intracellular lipid accumulation. In addition, compound 5, which regulated the transcription of genes associated with lipid uptake and synthesis, inhibited the accumulation of lipids.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...