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1.
Environ Int ; 185: 108531, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38428193

RESUMO

Gadani is internationally renowned for its extensive ship-breaking operations, positioning it as one of the globe's primary ship-breaking hubs. A comprehensive study was conducted to evaluate the presence of organic contaminants in the air within Gadani, encompassing the areas surrounding ship-breaking facilities, proximate residential settlements, and adjacent roadways. Passive air samplers were employed to collect a total of 30 air samples. The analytical results unveiled a notably elevated concentration of specific organic compounds, with a pronounced prevalence of polycyclic aromatic hydrocarbons (PAHs), short-chain chlorinated paraffins (SCCPs), and polychlorinated biphenyls (PCBs) at the ship-breaking yard. Notably, dichlorodiphenyltrichloroethanes (DDTs) and DDE were detected at substantially lower levels. In particular, sites in close proximity to ship-breaking activities exhibited elevated concentrations of PCBs (Σ7PCB 0.065429 to 7.345714 ng/sample), PAHs (Σ8PAH 2.44 to 134.23 ng/sample), and SCCPs (0.18 to 25.6 ng/sample). Conversely, DDTs and DDE demonstrated higher concentrations near residential settlements. The evaluation of Molecular Diagnostic Ratios for PAHs revealed anthracene/anthracene + phenanthrene ratios of 0.88, 0.69, and 0.5 for ship-breaking areas, roadside locations, and community surroundings, respectively. Furthermore, the benz[a]anthracene/benz-[a]anthracene + chrysene molecular ratios were measured at 0.77 (ship-breaking sites), 0.82 (roadside), and 0.83 (community), respectively. The molecular ratio of fluoranthene/fluoranthene + pyrene at ship-breaking sites was 0.23, while roadside and community ratios were 0.36 and 0.89, respectively. These findings underscore the significant contribution of ship-recycling activities to the atmospheric release of SCCPs, PCBs, and PAHs, emphasizing the global imperative for responsible ship recycling practices.


Assuntos
Fluorenos , Bifenilos Policlorados , Hidrocarbonetos Policíclicos Aromáticos , Bifenilos Policlorados/análise , Navios , Hidrocarbonetos Policíclicos Aromáticos/análise , Antracenos , Atmosfera , Monitoramento Ambiental/métodos
2.
PeerJ ; 12: e16859, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38410805

RESUMO

Background: The fall armyworm, Spodoptera frugiperda, is an agricultural pest of significant economic concern globally, known for its adaptability, pesticide resistance, and damage to key crops such as maize. Conventional chemical pesticides pose challenges, including the development of resistance and environmental pollution. The study aims to investigate an alternative solution: the application of soluble silicon (Si) sources to enhance plant resistance against the fall armyworm. Methods: Silicon dioxide (SiO2) and potassium silicate (K2SiO3) were applied to maize plants via foliar spray. Transcriptomic and biochemical analyses were performed to study the gene expression changes in the fall armyworm feeding on Si-treated maize. Results: Results indicated a significant impact on gene expression, with a large number of differentially expressed genes (DEGs) identified in both SiO2 and K2SiO3 treatments. Furthermore, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis identified critical DEGs involved in specific pathways, including amino acid, carbohydrate, lipid, energy, xenobiotics metabolisms, signal transduction, and posttranslational modification, significantly altered at both Si sources. Biochemical analyses further revealed that Si treatments inhibited several enzyme activities (glutamate dehydrogenase, trehalase, glucose-6-phosphate dehydrogenase, chitinase, juvenile hormone esterase, and cyclooxygenase while simultaneously inducing others (total protein, lipopolysaccharide, fatty acid synthase, ATPase, and cytochrome P450), thus suggesting a toxic effect on the fall armyworm. In conclusion, Si applications on maize influence the gene expression and biochemical activities of the fall armyworm, potentially offering a sustainable pest management strategy.


Assuntos
Dióxido de Silício , Zea mays , Animais , Spodoptera/genética , Zea mays/genética , Dióxido de Silício/metabolismo , Controle de Pragas , Perfilação da Expressão Gênica/veterinária
3.
Plants (Basel) ; 12(10)2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37653841

RESUMO

Heavy metal pollution is one of the major agronomic challenges. Tungsten (W) exposure leads to its accumulation in plants, which in turn reduces plant growth, inhibits photosynthesis and induces oxidative damage. In addition, the predicted increase in CO2 could boost plant growth under both optimal and heavy metal stress conditions. The aim of the present study was to investigate the effect of W on growth, photosynthetic parameters, oxidative stress and redox status in rye plants under ambient and elevated (eCO2) levels. To this end, rye plants were grown under the following conditions: ambient CO2 (aCO2, 420 ppm), elevated CO2 (eCO2, 720 ppm), W stress (350 mg kg-1 soil) and W+eCO2. W stress induced significant (p < 0.05) decreases in growth and photosynthesis, increases in oxidative damages (lipid peroxidation) and the antioxidant defense system, i.e., ascorbate (ASC), reduced glutathione (GSH), GSH reductase (GR), peroxidase (POX), catalase (CAT), superoxide dismutase (SOD), ASC peroxide (APX) and dehydroascorbate reductase (DHAR). On the other hand, eCO2 decreased W uptake and improved photosynthesis, which sequentially improved plant growth. The obtained results showed that eCO2 can decrease the phytotoxicity risks of W in rye plants. This positive impact of eCO2 on reducing the negative effects of soil W was related to their ability to enhance plant photosynthesis, which in turn provided energy and a carbon source for scavenging the reactive oxygen species (ROS) accumulation caused by soil W stress.

4.
Front Plant Sci ; 14: 1183185, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37521939

RESUMO

Elevating CO2 (eCO2) levels will change behavior and the effect of soil fertilizers and nutrients. Selenium NPs (SeNPs) have arisen as an alternative to conventional Se fertilizers to enrich crops. However, it remains unclear whether eCO2 will change the biological effects of soil SeNPs on plant growth and metabolism. The current study aimed to shed new light on the interactive impacts of eCO2 and SeNPs on wheat plants. Accordingly, the attempts were to reveal whether the application of SeNPs can modulate the eCO2 effects on wheat (Triticum aestivum L.) physiological and biochemical traits. With this goal, a pot experiment was carried out where the seeds were primed with SeNPs and plants were grown under two levels of CO2 concentrations (ambient CO2 (aCO2, 410 µmol CO2 mol-1; and eCO2 (710 µmol CO2 mol-1)) during six weeks after sowing. Although SeNPs+eCO2 treatment resulted in the highest accumulation of photosynthetic pigment content in leaves (+49-118% higher than control), strong evidence of the positive impacts on Rubisco activity (~+23%), and stomatal conductance (~+37%) was observed only under eCO2, which resulted in an improvement in photosynthesis capacity (+42%). When photosynthesis parameters were stimulated with eCO2, a significant improvement in dry matter production was detected, in particular under SeNPs+eCO2 which was 1.8 times higher than control under aCO2. The highest content of antioxidant enzymes, molecules, and metabolites was also recorded in SeNPs+eCO2, which might be associated with the nearly 50% increase in sodium content in shoots at the same treatment. Taken together, this is the first research documenting the effective synergistic impacts of eCO2 and SeNPs on the mentioned metabolites, antioxidants, and some photosynthetic parameters, an advantageous consequence that was not recorded in the individual application of these treatments, at least not as broadly as with the combined treatment.

5.
Nat Prod Res ; 37(4): 598-602, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35400256

RESUMO

The Chelonaplysilla genus possesses a numerous bioactive diterpenes with anti-inflammatory and cytotoxic effects. The current study aimed to assess the chemical composition of C. erecta crude extract (CECE) based on its metabolomic profile that has been integrated with neural network-based virtual screening and molecular docking using liquid chromatography with high resolution mass spectrometry (LCHR-MS). In addition to the estimation of the antitumor activity of the same extract via anti-interleukin-17A (IL-17) action, along with its formulated spanlastics preparation. The CECE markedly displayed growth inhibition for HepG-2 cells at IC50 value 16.5 ± 0.8 µg/mL, whereas the spanlastic formulation revealed more eminent antitumor effect against Caco-2 cells (IC50 = 2.8 ± 0.03 µg/mL). Among the dereplicated compounds, macfarlandin F (16) and pourewanone (25) demonstrated the highest potential with co-crystallized ligand 63 O within the active site of IL-17A in molecular docking studies. These findings rationalized the antitumor mechanism of marine organism for future chemotherapeutic applications.


Assuntos
Antineoplásicos , Diterpenos , Poríferos , Animais , Humanos , Simulação de Acoplamento Molecular , Células CACO-2 , Poríferos/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Diterpenos/farmacologia , Diterpenos/química
6.
Metabolites ; 12(5)2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35629955

RESUMO

Ephedra foeminea is a traditional medicinal plant used in the Eastern Mediterranean region. This study aims to investigate the chemical profiles of different solvent extracts of E. foeminea via an untargeted metabolomics approach, alongside determining their antioxidant capacities. E. foeminea samples collected from Jordan were macerated in solvents of varying polarities; dichloromethane/methanol, methanol, ethanol, ethyl acetate, and acetone. The crude extracts were subjected to comprehensive chemical profiling and metabolomics study using Gas chromatography-Mass spectrometry (GC-MS), Liquid chromatography-Mass spectrometry (LC-MS), and Nuclear Magnetic Resonance (NMR). The obtained data were analyzed using Venn diagrams, Principle Component Analysis (PCA), and Metabolite Enrichment Set Analysis (MESA). ABTS assay was performed to measure the crude extracts' antioxidant activity. MESA revealed the dominant chemical groups as amino acids, fatty acids, carboxylic acids, and carbohydrates. Results indicated that dichloromethane/methanol and methanolic extracts had the most distinct composition as well as the most unique compounds. The methanolic extract had the most potency (IC50 249.6 µg/mL) in the ABTS assay. However, no significant differences were found. In conclusion, solvents influenced the recovery of metabolites in E. foeminea and the antioxidant activity of the E. foeminea methanolic extract could be correlated to the abundant presence of diverse bioactive compounds.

7.
Polymers (Basel) ; 14(1)2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-35012205

RESUMO

Recently, more and more attention has been paid to the development of eco-friendly solid sorbents that are cost-effective, noncorrosive, have a high gas capacity, and have low renewable energy for CO2 capture. Here, we claimed the fabrication of a three-dimensional (3D) film of hollow nanocones with a large surface area (949.5 m2/g), a large contact angle of 136.3°, and high surface energy. The synthetic technique is based on an electrochemical polymerization process followed by a novel and simple strategy for pulling off the formed layers as a membrane. Although the polymer-coated substrates were reported previously, the membrane formation has not been reported elsewhere. The detachable capability of the manufactured layer as a membrane braked the previous boundaries and allows the membrane's uses in a wide range of applications. This 3D hollow nanocones membrane offer advantages over conventional ones in that they combine a π-electron-rich (aromatic ring), hydrophobicity, a large surface area, multiple amino groups, and a large pore volume. These substantial features are vital for CO2 capturing and storage. Furthermore, the hydrophobicity characteristic and application of the formed polymer as a CO2 sucker were investigated. These results demonstrated the potential of the synthesized 3D hollow polymer to be used for CO2 capturing with a gas capacity of about 68 mg/g and regeneration ability without the need for heat up.

8.
Sci Total Environ ; 810: 152046, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34856280

RESUMO

Plastic pollution and its impact on marine ecosystems are major concerns globally, and the situation was exacerbated after the outbreak of COVID-19. Clean-up campaigns took place during the summer season (June-August 2020) in two coastal cities in Egypt (Alexandria and Hurghada) and Jeddah, Saudi Arabia to document the abundance of beach debris through public involvement, and then remove it. A total of 3673, 255, and 848 items were collected from Alexandria, Hurghada, and Jeddah daily, respectively. Gloves and face masks (personal protective equipment "PPE") represent represented 40-60% of the total plastic items collected from each of the three cities, while plastic bags represented 7-20% of the total plastics litter collected from the same cities. The results indicated the presence of 2.79, 0.29, and 0.86 PPE item m-2 in Alexandria, Hurghada and Jeddah, respectively. This short focus provides an assessment of the environmental impacts of single-use gloves and masks used for COVID-19 protection from June to August 2020. To the best of our knowledge, this study presents the first such information from the Middle East, specifically Egypt and Saudi Arabia. It highlights the need for further knowledge and action, such as safe, sustainable, and transparent waste management processes related to COVID-19 to reduce the negative impacts now, as well as in future events. Furthermore, this study helps in achieving key components of the United Nation's Sustainable Development Goals (SDGs). This short focus can serve as a multipurpose document, not only for scientists of different disciplines but for social media and citizens in general.


Assuntos
COVID-19 , Equipamento de Proteção Individual , Ecossistema , Egito/epidemiologia , Humanos , Pandemias , Plásticos , SARS-CoV-2 , Arábia Saudita/epidemiologia
9.
Front Plant Sci ; 12: 650955, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33841479

RESUMO

Heat stress and abscisic acid (ABA) induce leaf senescence, whereas melatonin (MT) and gibberellins (GA) play critical roles in inhibiting leaf senescence. Recent research findings confirm that plant tolerance to diverse stresses is closely associated with foliage lifespan. However, the molecular mechanism underlying the signaling interaction of MT with GA and ABA regarding heat-induced leaf senescence largely remains undetermined. Herein, we investigated putative functions of melatonin in suppressing heat-induced leaf senescence in tomato and how ABA and GA coordinate with each other in the presence of MT. Tomato seedlings were pretreated with 100 µM MT or water and exposed to high temperature (38/28°C) for 5 days (d). Heat stress significantly accelerated senescence, damage to the photosystem and upregulation of reactive oxygen species (ROS), generating RBOH gene expression. Melatonin treatment markedly attenuated heat-induced leaf senescence, as reflected by reduced leaf yellowing, an increased Fv/Fm ratio, and reduced ROS production. The Rbohs gene, chlorophyll catabolic genes, and senescence-associated gene expression levels were significantly suppressed by MT addition. Exogenous application of MT elevated the endogenous MT and GA contents but reduced the ABA content in high-temperature-exposed plants. However, the GA and ABA contents were inhibited by paclobutrazol (PCB, a GA biosynthesis inhibitor) and sodium tungstate (ST, an ABA biosynthesis inhibitor) treatment. MT-induced heat tolerance was compromised in both inhibitor-treated plants. The transcript abundance of ABA biosynthesis and signaling genes was repressed; however, the biosynthesis genes MT and GA were upregulated in MT-treated plants. Moreover, GA signaling suppressor and catabolic gene expression was inhibited, while ABA catabolic gene expression was upregulated by MT application. Taken together, MT-mediated suppression of heat-induced leaf senescence has collaborated with the activation of MT and GA biosynthesis and inhibition of ABA biosynthesis pathways in tomato.

10.
Molecules ; 26(6)2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33809026

RESUMO

Chemical investigation of the methanolic extract of the Red Sea cucumber Holothuria spinifera led to the isolation of a new cerebroside, holospiniferoside (1), together with thymidine (2), methyl-α-d-glucopyranoside (3), a new triacylglycerol (4), and cholesterol (5). Their chemical structures were established by NMR and mass spectrometric analysis, including gas chromatography-mass spectrometry (GC-MS) and high-resolution mass spectrometry (HRMS). All the isolated compounds are reported in this species for the first time. Moreover, compound 1 exhibited promising in vitro antiproliferative effect on the human breast cancer cell line (MCF-7) with IC50 of 20.6 µM compared to the IC50 of 15.3 µM for the drug cisplatin. To predict the possible mechanism underlying the cytotoxicity of compound 1, a docking study was performed to elucidate its binding interactions with the active site of the protein Mdm2-p53. Compound 1 displayed an apoptotic activity via strong interaction with the active site of the target protein. This study highlights the importance of marine natural products in the design of new anticancer agents.


Assuntos
Antineoplásicos/farmacologia , Cerebrosídeos/farmacologia , Holothuria/química , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Cerebrosídeos/química , Cerebrosídeos/isolamento & purificação , Simulação por Computador , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Técnicas In Vitro , Células MCF-7 , Simulação de Acoplamento Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-mdm2/química , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/química
11.
J Biomed Mater Res A ; 109(7): 1113-1124, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32985059

RESUMO

The current study investigated the immunomodulating and osteoblast differentiation potential of the natural compounds from Leea macrophylla (LMN). Immunomodulatory effects have been investigated by the phagocytosis of Candida albicans using polymorphonuclear neutrophil cells in the in vitro slide method. A bioactivity-guided fractionation technique was used to evaluate the stimulating effect of L. macrophylla methanol extract on osteoblast differentiation using mouse osteoblastic cells. A low dose of LMN was found to stimulate the phagocytic effect better than a higher dose. The natural compounds from L. macrophylla have significantly increased alkaline phosphatase (ALP) and osteocalcin activities. The LMN promoted the osteoblast differentiation through upregulation of ALP, osteocalcin, and type 1 collagen in a dose-dependent manner. These natural compounds also upregulated ALP, osteocalcin, and type 1 collagen gene expressions. The data suggest that LMN has potential anabolic sequel on bone formation and osteoblast differentiation.


Assuntos
Expressão Gênica/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Extratos Vegetais/farmacologia , Vitaceae , Fosfatase Alcalina/genética , Animais , Células Cultivadas , Colágeno Tipo I/genética , Flavonoides/química , Flavonoides/farmacologia , Camundongos Endogâmicos C57BL , Osteoblastos/citologia , Osteocalcina/genética , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/química , Vitaceae/química
12.
Animal Model Exp Med ; 3(2): 140-151, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32613173

RESUMO

BACKGROUND: Justicia adhatoda and Ocimum tenuiflorum, locally known as bashok and tulsi, are two ethnomedicinally important herbs that have been using as dietary supplements for several therapeutic applications. This study evaluated the combined effect of both the herbs as an antioxidative and antihyperlipidemic agent. METHODS: Antihyperlipidemic effect was assessed in a high-fat diet-induced hyperlipidemic model in Wistar albino rats. The rats were treated orally with extracts of bashok (J adhatoda, 200 mg/kg bw), tulshi (O tenuiflorum, 200 mg/kg bw), and a combination of bashok and tulshi (50:50), as well as with a reference drug, atorvastatin (10 mg/kg/day), with or without high-fat diet for 14 days. The antioxidative effect was studied using established in vitro models. The studies were supported by experimentally testing the effects of the extracts on membrane stabilization and inhibition of protein denaturation. RESULTS: The results showed that the serum lipid profile was significantly decreased in the different treatment groups, with bashok having the greatest effect. Body weights, total serum protein, LDH, and relative liver and adipose tissue weights were markedly restored towards baseline values, the lowest atherogenic index being achieved with the combined extract. The combination treatment significantly enhanced total phenolic content and antioxidative capacity and greatly potentiated membrane stabilization, but inhibition of protein denaturation was not significantly affected. CONCLUSION: The data demonstrate that a combination of Justicia adhatoda and Ocimum tenuiflorum could be developed as a food supplement with antioxidative and antihyperlipidemic benefits.

13.
Int J Biol Macromol ; 156: 851-857, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32278600

RESUMO

Alhydwan, has been used in bakery products for many years in South of Yemen. Alhydwan primary function in bakery products is to inhibit moisture content during storage, leading to improved shelf life. However, as a fresh strategy to bread staling, no extensive study has been conducted to evaluate its potential. The present study therefore examined the alhydwan as a comparison with Carboxymethylcellulose (CMC) at 0.5% (w/w) level in dough rheology improvement, microstructure, quality parameters and delayed wheat bread staling. The CMC or alhydwan for farinograph characteristics comprising the dough's portrayed showed greater water absorption, while growth and stability time was significantly decreased. Staling of bread, the findings showed that in both alhydwan and CMC minimized crumb hardening frequency and enhanced freshness, quality and retention ability for moisture, making the bread softer and postponed staling. The microstructure of CMC or alhydwan supplemented formulation showed the distinguishable characteristics and constituents that could explain, to some degree, that the CMC and alhydwan had antistaling effect. The incorporation of alhydwan such as CMC into the formulation of bread could thus play a sustainable role in improving the quality of bread by having an extended shelf life.


Assuntos
Pão/análise , Carboximetilcelulose Sódica/química , Farinha/análise , Análise de Alimentos , Qualidade dos Alimentos , Triticum/química , Manipulação de Alimentos , Microscopia , Reologia
14.
Saudi J Biol Sci ; 27(12): 3700-3710, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34466056

RESUMO

This research investigated the reno-protective effect of Thunbergia laurifolia Linn. (TL) in a lead-induced toxicity test through the modulation of cell signaling pathways. The study carried out to evaluate the effect of TL leaf extracts in Swiss Albino mice exposed to lead acetate (PbAc). Prior to in vivo study, a probable kidney-protective effect of the plant leaf extract was presumed through an activity-specific (PASS) molecular docking analysis. In animal model study, albino mice were divided in seven groups and co-treated with PbAc and TL (100, 200 mg/kgBW) or vitamin E (100 mg/kgBW) for 38 days, whereas the untreated control, TL control, and vehicle control groups received sodium acetate, PbAc, sodium acetate plus mineral oil, respectively. At the end of treatment, blood and kidney tissue were collected for investigating Pb concentration, estimating biochemical profile, evaluating oxidative stress and inflammatory parameters. The histopathological change of kidney along with apoptosis was assessed from kidney sections using H & E staining and TUNEL assay. Pb-exposed mice were found to be increased concentration of Pb in the blood and kidney sample, which further led to increased MDA levels in the plasma, blood, and tissue. Followed by kidney damage, increased expression of TNF-α, iNOS, and COX-2 in kidney tissues were noticed, which were related to elevated TNF-α in the systemic circulation of Pb-treated mice. Co-treatment with TL or vitamin E significantly reduced altered structure and apoptosis of kidney tissues. Downregulation of inflammatory markers especially TNF-α, iNOS, and COX-2 with simultaneous improvement of renal function through reduced plasma BUN and creatinine levels demonstrate that TL act as a potential dietary supplement to detoxify Pb in kidney showing an antioxidant and anti-inflammatory effect.

15.
RSC Adv ; 10(38): 22730-22741, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35514559

RESUMO

A new triterpenoidal saponin identified as 3-O-[ß-d-glucopyranosyl-(1 → 2)-ß-d-glucopyranosyl-(1 → 4)-ß-d-xylopyranosyl]-2ß,3ß,16α-trihydroxyolean-12-en-23,28-dioic acid-28-O-α-l-rhamnopyranosyl-(1 → 4)-α-l-rhamnopyranosyl-(1 → 2)-ß-d-glucopyranosyl-(1 → 2)-α-l-arabinopyranoside 1 together with a new oleanane triterpene identified as 2ß,3ß,13α,22α-tetrahydroxy olean-23,28-dioic acid 2 and 6 known compounds (3-8) have been isolated from Gladiolus segetum Ker-Gawl corms. The structural elucidation of the isolated compounds was confirmed using different chemical and spectroscopic methods, including 1D and 2D NMR experiments as well as HR-ESI-MS. Moreover, the in vitro cytotoxic activity of the fractions and that of the isolated compounds 1-8 were investigated against five human cancer cell lines (PC-3, A-549, HePG-2, MCF-7 and HCT-116) using doxorubicin as a reference drug. The results showed that the saponin fraction exhibited potent in vitro cytotoxic activity against the five human cancer cell lines, whereas the maximum activity was exhibited against the PC-3 and A-549 cell lines with the IC50 values of 1.13 and 1.98 µg mL-1, respectively. In addition, compound 1 exhibited potent activity against A-549 and PC-3 with the IC50 values of 2.41 µg mL-1 and 3.45 µg mL-1, respectively. Interestingly, compound 2 showed the maximum activity against PC-3 with an IC50 of 2.01 µg mL-1. These biological results were in harmony with that of the molecular modeling study, which showed that the cytotoxic activity of compound 2 might occur through the inhibition of the HER-2 enzyme.

16.
AMB Express ; 9(1): 12, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30680548

RESUMO

Several approaches have been dedicated to activate the cryptic gene clusters in the genomes of actinomycetes for the targeted discovery of new fascinating biomedical lead structures. In the current study, N-acetylglucosamine was used to maximize the chemical diversity of sponge-derived actinomycete Actinokineospora spheciospongiae sp. nov. HR-ESI-MS was employed for dereplication study and orthogonal partial least square-discriminant analysis was applied to evaluate the HR-ESI-MS data of the different fractions. As a result, two new fridamycins H (1) and I (2), along with three known compounds actinosporin C (3), D (4), and G (5) were isolated from the solid culture of sponge-associated actinomycete Actinokineospora spheciospongiae sp. nov., elicited with N-acetylglucosamine. Characterization of the isolated compounds was pursued using mass spectrometry and NMR spectral data. Fridamycin H (1) exhibited significant growth inhibitory activity towards Trypanosoma brucei strain TC221. These results highlight the potential of elicitation in sponge-associated actinomycetes as an effective strategy for the discovery of new anti-infective natural products.

17.
Front Chem ; 6: 538, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30525020

RESUMO

Saccharomonospora sp. UR22 and Dietzia sp. UR66, two actinomycetes derived from the Red Sea sponge Callyspongia siphonella, were co-cultured and the induced metabolites were monitored by HPLC-DAD and TLC. Saccharomonosporine A (1), a novel brominated oxo-indole alkaloid, convolutamydine F (2) along with other three known induced metabolites (3-5) were isolated from the EtOAc extract of Saccharomonospora sp. UR22 and Dietzia sp. UR66 co-culture. Additionally, axenic culture of Saccharomonospora sp. UR22 led to isolation of six known microbial metabolites (6-11). A kinase inhibition assay results showed that compounds 1 and 3 were potent Pim-1 kinase inhibitors with an IC50 value of 0.3 ± 0.02 and 0.95 ± 0.01 µM, respectively. Docking studies revealed the binding mode of compounds 1 and 3 in the ATP pocket of Pim-1 kinase. Testing of compounds 1 and 3 displayed significant antiproliferative activity against the human colon adenocarcinoma HT-29, (IC50 3.6 and 3.7 µM, respectively) and the human promyelocytic leukemia HL-60, (IC50 2.8 and 4.2 µM, respectively). These results suggested that compounds 1 and 3 act as potential Pim-1 kinase inhibitors that mediate the tumor cell growth inhibitory effect. This study highlighted the co-cultivation approach as an effective strategy to increase the chemical diversity of the secondary metabolites hidden in the genomes of the marine actinomycetes.

18.
Mar Drugs ; 16(9)2018 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-30134565

RESUMO

A new cyclic hexapeptide, nocardiotide A (1), together with three known compounds-tryptophan (2), kynurenic acid (3), and 4-amino-3-methoxy benzoic acid (4)-were isolated and identified from the broth culture of Nocardiopsis sp. UR67 strain associated with the marine sponge Callyspongia sp. from the Red Sea. The structure elucidation of the isolated compounds were determined based on detailed spectroscopic data including ¹D and ²D nuclear magnetic resonance (NMR) experimental analyses in combination with high resolution electrospray ionization mass spectrometry (HR-ESI-MS), while the absolute stereochemistry of all amino acids components of nocardiotide A (1) was deduced using Marfey's method. Additionally, ten known metabolites were dereplicated using HR-ESI-MS analysis. Nocardiotide A (1) displayed significant cytotoxic effects towards the murine CT26 colon carcinoma, human HeLa cervix carcinoma, and human MM.1S multiple myeloma cell lines. The results obtained revealed sponge-associated Nocardiopsis as a substantial source of lead natural products with pronounced pharmacological activities.


Assuntos
Actinobacteria/química , Antineoplásicos/farmacologia , Callyspongia/microbiologia , Peptídeos Cíclicos/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Organismos Aquáticos/microbiologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Oceano Índico , Camundongos , Neoplasias/tratamento farmacológico , Peptídeos Cíclicos/química , Peptídeos Cíclicos/isolamento & purificação
19.
PLoS One ; 12(6): e0177316, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28609451

RESUMO

Natural products have been used for medical applications since ancient times. Commonly, natural products are structurally complex chemical compounds that efficiently interact with their biological targets, making them useful drug candidates in cancer therapy. Here, we used cell-based phenotypic profiling and image-based high-content screening to study the mode of action and potential cellular targets of plants historically used in Saudi Arabia's traditional medicine. We compared the cytological profiles of fractions taken from Juniperus phoenicea (Arar), Anastatica hierochuntica (Kaff Maryam), and Citrullus colocynthis (Hanzal) with a set of reference compounds with established modes of action. Cluster analyses of the cytological profiles of the tested compounds suggested that these plants contain possible topoisomerase inhibitors that could be effective in cancer treatment. Using histone H2AX phosphorylation as a marker for DNA damage, we discovered that some of the compounds induced double-strand DNA breaks. Furthermore, chemical analysis of the active fraction isolated from Juniperus phoenicea revealed possible anti-cancer compounds. Our results demonstrate the usefulness of cell-based phenotypic screening of natural products to reveal their biological activities.


Assuntos
Antineoplásicos/farmacologia , Ensaios de Triagem em Larga Escala/métodos , Preparações de Plantas/farmacologia , Inibidores da Topoisomerase/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Brassicaceae/química , Caspase 9/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Citrullus colocynthis/química , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Dano ao DNA , Células HeLa , Histonas/metabolismo , Humanos , Juniperus/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas/métodos , Estrutura Molecular , Fosforilação/efeitos dos fármacos , Preparações de Plantas/química , Arábia Saudita , Inibidores da Topoisomerase/química , Proteína Supressora de Tumor p53/metabolismo
20.
Mar Drugs ; 12(5): 2771-89, 2014 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-24824024

RESUMO

The diversity of actinomycetes associated with marine sponges collected off Fsar Reef (Saudi Arabia) was investigated in the present study. Forty-seven actinomycetes were cultivated and phylogenetically identified based on 16S rRNA gene sequencing and were assigned to 10 different actinomycete genera. Eight putatively novel species belonging to genera Kocuria, Mycobacterium, Nocardia, and Rhodococcus were identified based on sequence similarity values below 98.2% to other 16S rRNA gene sequences available in the NCBI database. PCR-based screening for biosynthetic genes including type I and type II polyketide synthases (PKS-I, PKS-II) as well as nonribosomal peptide synthetases (NRPS) showed that 20 actinomycete isolates encoded each at least one type of biosynthetic gene. The organic extracts of nine isolates displayed bioactivity against at least one of the test pathogens, which were Gram-positive and Gram-negative bacteria, fungi, human parasites, as well as in a West Nile Virus protease enzymatic assay. These results emphasize that marine sponges are a prolific resource for novel bioactive actinomycetes with potential for drug discovery.


Assuntos
Actinobacteria/química , Poríferos/microbiologia , Actinobacteria/classificação , Actinobacteria/genética , Animais , Antibacterianos/biossíntese , Antibacterianos/farmacologia , Antiprotozoários/farmacologia , Bactérias/efeitos dos fármacos , Biodiversidade , Fungos/efeitos dos fármacos , Oceano Índico , Testes de Sensibilidade Microbiana , Filogenia , Inibidores de Proteases/farmacologia , Arábia Saudita , Tripanossomicidas/farmacologia , Trypanosoma brucei brucei/efeitos dos fármacos
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