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1.
Molecules ; 28(20)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37894504

RESUMO

Essential oils are naturally occurring multicomponent combinations of isoprenoids with distinctive odors that are produced by aromatic plants from mevalonic acid. They are extensively applied in aromatherapy for the treatment of various ailments. To investigate the potential therapeutic value of the ingredients in Launaea mucronata essential oil (EO), gas chromatography-mass spectrometry (GC-MS) analysis was used for essential oil characterization. Then, 2,2-diphenyl-1-picrylhydrazyl (DPPH), ß-carotene/linoleic acid, and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays were used to evaluate the antioxidants. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was used to estimate the cytotoxicity. Following a thorough analysis of the GC-MS chromatogram, 87 components representing 97.98% of the entire EO mixture were identified. N-eicosane (10.92%), 2E,6Z-farnesol (10.74%), and 2Z,6E-farnesyl acetone (46.35%) were determined to be the major components of the oil. When the produced EO was evaluated for its antioxidant properties, it showed a strong inhibitory effect (%) of 65.34 at a concentration of 80 µg/mL. The results (g/mL) showed a positive response against the tested cell lines for HCT-116, MCF-7, and HepG2 (8.45, 10.24, and 6.78 g/mL, respectively). A high-concentration mixture of deadly components consisting of farnesol, bisabolol, eicosane, and farnesyl acetone may be responsible for this significant cytotoxic action, which was especially noticeable in the HepG2 cell line. Molecular docking occurred between farnesol and farnesyl acetone with the target residues of topoisomerases I and II, CDK4/cyclD1, and Aurora B kinases; these showed binding free energies ranging from -4.5 to -7.4 kcal/mol, thus demonstrating their antiproliferative action. In addition, farnesol and farnesyl acetone fulfilled most of the ADME and drug-likeness properties, indicating their activity.


Assuntos
Antineoplásicos , Asteraceae , Óleos Voláteis , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Antioxidantes/farmacologia , Antioxidantes/química , Farneseno Álcool , Arábia Saudita , Acetona , Simulação de Acoplamento Molecular , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Asteraceae/química
2.
Pharmaceuticals (Basel) ; 16(3)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36986562

RESUMO

COVID-19 infection is now considered one of the leading causes of human death. As an attempt towards the discovery of novel medications for the COVID-19 pandemic, nineteen novel compounds containing 1,2,3-triazole side chains linked to phenylpyrazolone scaffold and terminal lipophilic aryl parts with prominent substituent functionalities were designed and synthesized via a click reaction based on our previous work. The novel compounds were assessed using an in vitro effect on the growth of SARS-CoV-2 virus-infested Vero cells with different compound concentrations: 1 and 10 µM. The data revealed that most of these derivatives showed potent cellular anti-COVID-19 activity and inhibited viral replication by more than 50% with no or weak cytotoxic effect on harboring cells. In addition, in vitro assay employing the SARS-CoV-2-Main protease inhibition assay was done to test the inhibitors' ability to block the common primary protease of the SARS-CoV-2 virus as a mode of action. The obtained results show that the one non-linker analog 6h and two amide-based linkers 6i and 6q were the most active compounds with IC50 values of 5.08, 3.16, and 7.55 µM, respectively, against the viral protease in comparison to data of the selective antiviral agent GC-376. Molecular modeling studies were done for compound placement within the binding pocket of protease which reveal conserved residues hydrogen bonding and non-hydrogen interactions of 6i analog fragments: triazole scaffold, aryl part, and linker. Moreover, the stability of compounds and their interactions with the target pocket were also studied and analyzed by molecular dynamic simulations. The physicochemical and toxicity profiles were predicted, and the results show that compounds behave as an antiviral activity with low or no cellular or organ toxicity. All research results point to the potential usage of new chemotype potent derivatives as promising leads to be explored in vivo that might open the door to rational drug development of SARS-CoV-2 Main protease potent medicines.

3.
Bioorg Chem ; 133: 106404, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36812829

RESUMO

New phthalazone tethered 1,2,3-triazole derivatives 12-21 were synthesized utilizing the Cu(I)-catalyzed click reactions of alkyne-functionalized phthalazone 1 with functionalized azides 2-11. The new phthalazone-1,2,3-triazoles structures 12-21 were confirmed by different spectroscopic tools, like IR; 1H, 13C, 2D HMBC and 2D ROESY NMR; EI MS, and elemental analysis. The antiproliferative efficacy of the molecular hybrids 12-21 against four cancer cell lines was evaluated, including colorectal cancer, hepatoblastoma, prostate cancer, breast adenocarcinoma, and the normal cell line WI38. The antiproliferative assessment of derivatives 12-21 showed potent activity of compounds 16, 18, and 21 compared to the anticancer drug doxorubicin. Compound 16 showed selectivity (SI) towardthe tested cell lines ranging from 3.35 to 8.84 when compared to Dox., that showed SI ranged from 0.75 to 1.61. Derivatives 16, 18 and 21 were assessed towards VEGFR-2 inhibitory activity and result in that derivative 16 showed the potent activity (IC50 = 0.123 µM) in comparison with sorafenib (IC50 = 0.116 µM). Compound 16 caused an interference with the cell cycle distribution of MCF7 and increased the percentage of cells in S phase by 1.37-fold. In silico molecular docking of the effective derivatives 16, 18, and 21 against vascular endothelial growth factor receptor-2 (VEGFR-2) confirmed the formation of stable protein-ligand interactions within the pocket.


Assuntos
Antineoplásicos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Simulação de Acoplamento Molecular , Estrutura Molecular , Inibidores de Proteínas Quinases/farmacologia , Relação Estrutura-Atividade , Triazóis/farmacologia , Triazóis/química , Fator A de Crescimento do Endotélio Vascular/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores
4.
J Biomol Struct Dyn ; 41(21): 12411-12425, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36661285

RESUMO

Treatment options for the management of breast cancer are still inadequate. This inadequacy is attributed to the lack of effective targeted medications, often resulting in the recurrence of metastatic disorders. Cumulative evidence suggests that epidermal growth factor receptor (EGFR-TK) and cyclin-dependent kinases-9 (CDK-9) overexpression correlates with worse overall survival in breast cancer patients. Pyranopyrazole and pyrazolone are privileged options for the development of anticancer agents. Inspired by this proven scientific fact, we report here the synthesis of two new series of suggested anticancer molecules incorporating both heterocycles together with their characterization by IR, 1H NMR, 13C NMR, 13C NMR-DEPT, and X-ray diffraction methods. An attempt to get the pyranopyrazole-gold complexes was conducted but unexpectedly yielded benzylidene-2,4-dihydro-3H-pyrazol-3-one instead. This unexpected result was confirmed by X-ray crystallographic analysis. All newly synthesized compounds were assessed for their anti-proliferative activity against two different human breast cancer cells, and the obtained results were compared with the reference drug Staurosporine. The target compounds revealed variable cytotoxicity with IC50 at a low micromolar range with superior selectivity indices. Target enzyme EGFR-TK and CDK-9 assays showed that compounds 22 and 23 effectively inhibited both biological targets with IC50 values of 0.143 and 0.121 µM, respectively. Molecular docking experiments and molecular dynamics simulation were also conducted to further rationalize the in vitro obtained results.Communicated by Ramaswamy H. Sarma.


Assuntos
Antineoplásicos , Neoplasias da Mama , Pirazolonas , Humanos , Feminino , Relação Estrutura-Atividade , Proliferação de Células , Cristalografia por Raios X , Simulação de Acoplamento Molecular , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Antineoplásicos/química , Neoplasias da Mama/patologia , Pirazolonas/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química
5.
Antibiotics (Basel) ; 11(12)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36551340

RESUMO

Marine sponges create a wide range of bioactive secondary metabolites, as documented throughout the year. Several bioactive secondary metabolites were isolated from different members of Callyspongia siphonella species. This study aimed for isolation and structural elucidation of major metabolites in order to investigate their diverse bioactivities such as antimicrobial and anti-biofilm activities. Afterwards, a molecular docking study was conducted, searching for the possible mechanistic pathway of the most bioactive metabolites. Extraction, fractionation, and metabolomics analysis of different fractions was performed in order to obtain complete chemical profile. Moreover, in vitro assessment of different bioactivities was performed, using recent techniques. Additionally, purification, structural elucidation of high features using recent chromatographic and spectroscopic techniques was established. Finally, AutoDock Vina software was used for the Pharmacophore-based docking-based analysis. As a result, DCM (dichloromethane) fraction exerted the best antibacterial activity using disc diffusion method; particularly against S. aureus with an inhibition zone of 6.6 mm. Compound 11 displayed a considerable activity against both MRSA (Methicillin-resistant Staphyllococcus aureus) and Staphyllococcus aureus with inhibition ratios of 50.37 and 60.90%, respectively. Concerning anti-biofilm activity, compounds 1 and 2 displayed powerful activity with inhibition ratios ranging from 39.37% to 70.98%. Pharmacophore-based docking-based analysis suggested elongation factor G (EF-G) to be a probable target for compound 11 (siphonellinol C) that showed the best in vitro antibacterial activity, offering unexplored potential for new drugs and treatment candidates.

6.
Food Sci Nutr ; 10(11): 3544-3561, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36348778

RESUMO

Carvacrol is a major natural constituent and is significantly present as an essential oil in aromatic plants and is well known for its numerous biological activities. Therapeutic properties of carvacrol have been demonstrated as anti-oxidant, anticancer, diabetes prevention, cardioprotective, anti-obesity, hepatoprotective and reproductive role, antiaging, antimicrobial, and immunomodulatory properties. The carvacrol biosynthesis has been mediated through mevalonate pathway. Carvacrol has the anticancer ability against malignant cells via decreasing the expressions of matrix metalloprotease 2 and 9, inducing apoptosis, enhancing the expression of pro-apoptotic proteins, disrupting mitochondrial membrane, suppressing extracellular signal-regulated kinase 1/2 mitogen-activated protein kinase signal transduction, and also decreasing the phosphoinositide 3-kinase/protein kinase B. It also decreased the concentrations of alanine aminotransferase, alkaline phosphatase and aspartate aminotransferase, and gamma-glutamyl transpeptidase as well as also restored liver function, insulin level, and plasma glucose level. Carvacrol also has been found to exert antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, Coagulase-negative staphylococcus, Salmonella spp., Enterococcus sp. Shigella, and Escherichia coli. The current review article summarizes the health-promoting perspectives of carvacrol through various pathways.

7.
Pharmaceuticals (Basel) ; 15(9)2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36145355

RESUMO

In this study new sulphamethoxazole derivatives (S1-S4, S6-S12, and S14-S22) were designed and synthesized and their structures were fully characterized and validated using NMR, mass, and IR spectroscopy, as well as elemental analyses. All new derivatives (S1-S22) were assayed against human carbonic anhydrase (hCAs IX and XII) for their inhibitory activities. hCAs IX and XII were chosen due to the fact that CAIX expression is recognized as a hypoxia marker with a poor prognosis in breast cancer. When compared to Dorzolamide HCl as a standard reference, derivatives S2, S3, S8, S9, and S15 had the most effective inhibition with low IC50 values. The active compounds were further evaluated against hCAs I and II inhibitory activity and compounds S8, S9 and S15 showed the least inhibitory effect compared to the reference standard, acetazolamide, indicating that their effect in normal cells is the lowest. Cell viability tests for the selected compounds were carried out on MCF7 (normoxia and hypoxia) and on the normal breast cell line (MCF10a) with Staurosporine as a standard. The results showed that compound S15 had a highly potent cytotoxic effect. Furthermore, cell cycle analysis results showed that compound S15 triggered cell cycle arrest and apoptosis in G1/S of MCF7 cancer cells. Finally, molecular docking was performed to point out the possible explanation for the vital structural features and key-interactions exerted by our ligands with hCAs IX and XII that might share additional designs and highlight possible leads for a hopeful anticancer agent. Consequently, sulphamethoxazole Derivative S15 could be the potential lead for emerging selective cytotoxic compounds directing h CAs IX and XII.

8.
Plants (Basel) ; 11(14)2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35890504

RESUMO

Origanum majoranum L. is a Lamiaceae medicinal plant with culinary and ethnomedical applications. Its biological and phytochemical profiles have been extensively researched. Accordingly, this study aimed to investigate the chemical composition and the antibacterial and antioxidant properties of O. majoranum high features, as well as to search for techniques for activity optimization. A metabolomics study of the crude extract of O. majoranum using liquid chromatography-high-resolution electrospray ionization mass spectrometry (LC ± HR ± ESI ± MS) was conducted. Five fractions (petroleum ether, dichloromethane, ethyl acetate, n-butanol, and aqueous) were derived from the total extract of the aerial parts. Different chromatographic methods and NMR analysis were utilized to purify and identify the isolated phenolics (high features). Moreover, the antimicrobial, antibiofilm, and antioxidant activity of phenolics were performed. Results showed that metabolomic profiling of the crude extract of O. majoranum aerial parts revealed the presence of a variety of phytochemicals, predominantly phenolics, resulting in the isolation and identification of seven high-feature compounds comprising two phenolic acids, rosmarinic and caffeic acids, one phenolic diterpene, 7-methoxyepirosmanol, in addition to four flavonoids, quercetin, hesperitin, hesperidin, and luteolin. On the other hand, 7-methoxyepirosmanol (OM1) displayed the most antimicrobial and antioxidant potential. Such a phenolic principal activity improvement seems to be established after loading on gold nanoparticles.

9.
Molecules ; 27(9)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35566313

RESUMO

Mentha is an aromatic plant used since antiquity for its pharmaceutical virtues. The climate of Saudi Arabia favors the growth of aromatic plants including Mentha suaveolens L. The aim of this study is to analyze the volatile oils of different parts of fresh and dried Mentha suaveolens L. grown in Saudi Arabia (Aljouf area) using Gas Chromatography/Mass Spectrometry (GC/MS) and Gas Chromatography Flame Ionization Detector (GC/FID) techniques, to recognize the effect of drying on chemical composition, then to evaluate the antioxidant and antifungal activities of different extracts. In total, 118 compounds were identified via GC/MS and GC/FID, in which carvone is the main volatile constituent (stems, leaves, whole plant 45-64%). This investigation deduces that Mentha belonged to the carvone chemotype. Then, the analysis of non-volatile constituents of fresh and dried Mentha was performed by HPLC. The main phenolic compound of fresh and dried Mentha for different parts was rosmarinic acid (ranging from 28,002.5 to 6558 µg/g). The ethanolic extract of fresh stem showed the highest antifungal activity (53% inhibition) compared with miconazole (60% inhibition) but the ethanoic extract of dry stem showed no activity. Additionally, all ethanolic extracts, whether for fresh or dry Mentha, have antioxidant activity more than 90% while the antioxidant activity of whole plant volatile oil is equal to 53.33%. This research shows that M. suaveolens L. could be applied to manufacture natural antioxidants, antifungal, and flavoring agents.


Assuntos
Mentha , Óleos Voláteis , Antifúngicos/química , Antioxidantes/química , Cromatografia Gasosa-Espectrometria de Massas , Mentha/química , Óleos Voláteis/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Arábia Saudita
10.
Molecules ; 27(4)2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35208952

RESUMO

For most researchers, discovering new anticancer drugs to avoid the adverse effects of current ones, to improve therapeutic benefits and to reduce resistance is essential. Because the COX-2 enzyme plays an important role in various types of cancer leading to malignancy enhancement, inhibition of apoptosis, and tumor-cell metastasis, an indispensable objective is to design new scaffolds or drugs that possess combined action or dual effect, such as kinase and COX-2 inhibition. The start compounds A1 to A6 were prepared through the diazo coupling of 3-aminoacetophenone with a corresponding phenol and then condensed with two new chalcone series, C7-18. The newly synthesized compounds were assessed against both COX-2 and epidermal growth factor receptor (EGFR) for their inhibitory effect. All novel compounds were screened for cytotoxicity against five cancer cell lines. Compounds C9 and G10 exhibited potent EGFR inhibition with IC50 values of 0.8 and 1.1 µM, respectively. Additionally, they also displayed great COX-2 inhibition with IC50 values of 1.27 and 1.88 µM, respectively. Furthermore, the target compounds were assessed for their cytotoxicity against pancreatic ductal cancer (Panc-1), lung cancer (H-460), human colon cancer (HT-29), human malignant melanoma (A375) and pancreatic cancer (PaCa-2) cell lines. Interestingly, compounds C10 and G12 exhibited the strongest cytotoxic effect against PaCa-2 with average IC50 values of 0.9 and 0.8 µM, respectively. To understand the possible binding modes of the compounds under investigation with the receptor cites of EGFR and COX-2, a virtual docking study was conducted.


Assuntos
Antineoplásicos , Chalconas , Inibidores de Ciclo-Oxigenase 2 , Proteínas de Neoplasias , Neoplasias , Inibidores de Proteínas Quinases , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Chalconas/síntese química , Chalconas/química , Chalconas/farmacologia , Inibidores de Ciclo-Oxigenase 2/síntese química , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/antagonistas & inibidores , Humanos , Estrutura Molecular , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia
11.
Saudi J Biol Sci ; 28(9): 5349-5358, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34466114

RESUMO

A promising Cordia myxa fruit (CMF) extract targets an additional incorporation in functional foods. It retains appropriate health welfares owing to its antioxidant properties with limited incorporation in food matrices due its hydrophobicity. Therefore, CMF extract micro- and nanocapsulation was performed to protect and facilitate consistency of produced hydrophobic foods matrices. Furthermore, to determine its phytochemicals, antioxidant, and cytotoxic effects by applying analytical HPLC, FRAP and SRB assay, respectively. HPLC analysis of the tested extracts revealed the presence of, 25.59 ± 1.78 mg catechin/g, 69.68 ± 4.20 mg quercetin/g, and 112.72 ± 8.38 mg gallic acid/g extract. The CMF extract displayed a potent DPPH radicals' scavenger and FRAP high reduction capability in a dose-dependent manner. The potent pharmacological activities of CMF extract may be ascribed to high concentration of polyphenolics including flavonoids which strongly reported to possess an antitumor and antioxidant activities. To confirm the efficient CMF incorporation in micro- and nanosystems and their thermal stabilities to withstand the high temperatures applied during some food processing. DSC of the apparent melt of non-capsulated CMF and encapsulated forms (MCMF and NCMF) in sodium alginate gel and beads was studied. Results showed that melting point of CMF extract (86.17 °C) indicating its inability whereas the MCMF and NCMF melting points (226.45 and 383.87 °C, respectively) demonstrating the capability of expending alginate - packaging material to shield the vital active compounds of C. myxa fruit to be applied in different targeted delivery products especially that disclosed to high thermal treatments.

12.
Biomed Pharmacother ; 98: 446-453, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29278855

RESUMO

Olive oil and leaf extract have several health benefits; however, their beneficial effect against fluoxetine-induced liver injury has not been investigated. The present study aimed to scrutinize the impact of fluoxetine on the liver of rats and to evaluate the protective effects of olive oil and leaf extract. Rats received fluoxetine orally at dose of 10 mg/kg body weight for 7 consecutive days. The fluoxetine-induced rats were concurrently treated with olive oil or leaf extract. At the end of the experiment, blood and liver samples were collected for analysis. Fluoxetine administration significantly increased circulating ALT, AST, ALP and the pro-inflammatory cytokines TNF-α and IL-1ß levels in rats. Histological analysis showed several alterations, such as inflammatory cells infiltration, hepatocyte vacuolation and dilated sinusoids in the liver of fluoxetine-induced rats. Concurrent supplementation of olive oil and olive leaf extract significantly reduced circulating liver function marker enzymes and pro-inflammatory cytokines, and prevented fluoxetine-induced histological alterations. Both olive oil and leaf extract significantly decreased liver lipid peroxidation and nitric oxide, and ameliorated liver glutathione, superoxide dismutase, catalase and glutathione peroxidase. In addition, olive oil and leaf extract prevented fluoxetine-induced apoptosis in the liver of rats as evidenced by decreased expression of Bax and caspase-3, and up-regulated expression of Bcl-2. In conclusion, olive oil and leaf extract protect against fluoxetine-induced liver injury in rats through attenuation of oxidative stress, inflammation and apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Inflamação/tratamento farmacológico , Azeite de Oliva/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Alanina Transaminase/metabolismo , Animais , Antioxidantes/metabolismo , Aspartato Aminotransferases/metabolismo , Catalase/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Citocinas/metabolismo , Fluoxetina/efeitos adversos , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Hepatócitos/metabolismo , Inflamação/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Ratos , Superóxido Dismutase/metabolismo
13.
Food Chem ; 187: 7-13, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25976991

RESUMO

A comparative study was carried out between two beef-like flavourings prepared by conventional and microwave heating (CBF and MBF) of enzymatic hydrolysate of mushroom protein with other flavour precursors. GC-MS analysis of the isolated volatiles revealed that the thiol containing compounds were the predominate in both samples. However, MBF comprised higher concentration of these compounds (13.84 ± 0.06%) than CBF (10.74 ± 0.06%). The effect of microencapsulation with gum Arabic by using spray drying on the odour profile and volatile compounds of the two encapsulated samples (E-CBF and E-MBF) was investigated. The results revealed significant qualitative and quantitative variations in the volatiles of both samples. The highly volatile compounds decreased remarkably in concentration with encapsulation, while the pyrazines, thiazoles and disulphides showed opposite trend. The significant decrease in the thiol containing compounds in E-CBF and E-MBF were attributed to their oxidation to other compounds such as disulphide compounds which showed significant increase in the encapsulated samples.


Assuntos
Agaricales/química , Composição de Medicamentos/métodos , Aromatizantes/análise , Manipulação de Alimentos/métodos , Proteínas Fúngicas/química , Micro-Ondas , Aminoácidos/análise , Animais , Bovinos , Dessecação , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Humanos , Hidrólise , Masculino , Odorantes/análise , Carne Vermelha , Paladar , Compostos Orgânicos Voláteis/análise
14.
J Agric Food Chem ; 59(13): 7346-52, 2011 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-21557618

RESUMO

The importance of the linkage between nutrition and health is a hot issue. Like other food-related sectors, the meat industry is undergoing foremost transformations, driven among other things by changes in consumer requirements. The present study was designed to evaluate the lipid stability and antioxidative potential of leg and breast microsomal fraction of broiler meat fed on ALA and ATA. For the first 3 weeks of growth, broilers were fed on feed supplemented with ATA (200 mg/kg of feed) and during the last 3 weeks broilers were fed on feed supplemented with ALA (25, 75, 150 mg/kg of feed) and a constant level of ATA (200 mg/kg of feed). The body weight of the carcass was measured after every week of growth until 6 weeks. Positive correlation between the antioxidant activity and the TPC was observed. Higher values of TBARS were detected in leg muscles than in breast muscles. HPLC data revealed ALA and ATA contents were higher in T(4) (leg, 5.55 ± 0.19 and 3.87 ± 0.15 µg/mg of protein; breast, 5.63 ± 0.20 and 2.03 ± 0.10 µg/mg of protein, respectively) and lowest in T(5) (ALA, leg, 1.40 ± 0.06 µg/mg of protein; breast, 1.54 ± 0.05 µg/mg of protein; ATA, leg, 1.25 ± 0.06 µg/mg of protein; breast, 0.63 ± 0.008 µg/mg of protein), in which the only oxidized oil was used. Oxidized oil in feed reduced weight gain and increased TBARS, whereas TPC, DPPH, ALA, and ATA values decreased in both leg and breast meat.


Assuntos
Antioxidantes/análise , Lipídeos/análise , Carne/análise , Microssomos/química , Ácido Tióctico/administração & dosagem , alfa-Tocoferol/administração & dosagem , Animais , Galinhas , Dieta , Estabilidade de Medicamentos , Músculo Esquelético/química , Músculo Esquelético/ultraestrutura , Substâncias Reativas com Ácido Tiobarbitúrico/análise
15.
J Agric Food Chem ; 57(12): 5265-70, 2009 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-19462981

RESUMO

Essential oil, dichloromethane extract, and ethanol extract were prepared from fresh Schinus terebinthifolius leaves cultivated in Egypt. The essential oil was analyzed by gas chromatography and gas chromatography/mass spectrometry. The essential oil comprised 4.97% monoterpenes, 56.96% sesquiterpenes, 34.37% oxygenated monoterpenes, and 3.32% oxygenated sesquiterpenes. The major compounds in the essential oil were cis-beta-terpineol (GC peak area%, 17.87%), (E)-caryophyllene (17.56%), beta-cedrene (9.76%), and citronellal (7.03%). The major phenolic compounds identified in the ethanol extract were caffeic acid (5.07 mg/100 mg extract), coumaric acid (1.64 mg), and syringic acid (1.59 mg). The antioxidant activity of ethanol extract, which was comparable with that of butylhydroquinone, was superior to essential oil and dichloromethane extract in 2,2-diphenylpicrylhydrazyl and beta-carotene/bleaching assays. The dichloromethane extract exhibited the greatest antimicrobial activity against 6 strains, followed by the ethanol extract and the essential oil.


Assuntos
Anacardiaceae/química , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Egito , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Folhas de Planta/química , Óleos de Plantas/química , Óleos de Plantas/farmacologia
16.
J AOAC Int ; 89(1): 149-53, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16512240

RESUMO

A gas chromatographic method, along with a headspace solid-phase microextraction (HS-SPME), was developed for the determination of acrylamide formed in Maillard reaction model systems. The developed method was validated by liquid chromatography/mass spectrometry. A headspace sample was collected from an aqueous acrylamide solution (100 microg/mL) by SPME and directly injected into a gas chromatograph equipped with a nitrogen-phosphorus detector. The recovery of acrylamide from an aqueous solution was satisfactory, i.e, >93% under the conditions used. Acrylamide formed in an asparagine/D-glucose (molar ratio, 1/2) Maillard reaction model system heated at 150 and 170 degrees C for 20 min was collected and analyzed by the newly developed method using gas chromatography with nitrogen-phosphorus detection and HS-SPME. The amounts of acrylamide were 318 +/- 33 microg/g asparagine from a sample heated at 150 degrees C and 3329 +/- 176 microg/g asparagine from a sample heated at 170 degrees C. Addition of cysteamine or glutathione to the above model system reduced acrylamide formation. Acrylamide formation was not observed when cysteamine or glutathione was added to asparagine in the above model systems to obtain equimolar concentrations of both compounds. This newly developed method is simple and sensitive, and requires no solvent extraction.


Assuntos
Acrilamida/análise , Asparagina/análise , Técnicas de Química Analítica/métodos , Cromatografia Gasosa/instrumentação , Cromatografia Gasosa/métodos , Análise de Alimentos/métodos , Glucose/química , Asparagina/química , Contaminação de Alimentos , Reação de Maillard , Modelos Químicos , Nitrogênio/química , Fósforo/química , Sensibilidade e Especificidade , Solventes/química , Temperatura
17.
Nahrung ; 47(1): 41-5, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12653437

RESUMO

Leaves from Eucalvptus camaldulensis var. brevirostris trees, planted in the Nile delta in Egypt, were examined for the antioxidant activity of their nonvolatile compounds. The extracts obtained by ethanol digestion and by supercritical fluid extraction (SFE; CO2 with 15% ethanol) showed the most promising antioxidative activities. In order to identify the most active compounds, both extracts were subjected to a semipreparative reversed-phase HPLC separation, the main fractions were collected, tested for antioxidative activity and analysed by different chromatographical and spectroscopical methods for identification of the most relevant compounds. Gallic and ellagic acid were found to be the prevailing antioxidants in the ethanolic extract. The main two compounds of the SFE extract with antioxidative activity revealed to be flavones. To a high degree of probability they were identified as 5-hydroxy-7,4'-dimethoxy flavone and 5-hydroxy-7,4'-dimethoxy-8-methyl flavone, respectively. The extracts obtained by ethanoldigestion were dried and administered to rats for toxicity evaluation (up to 3 g/kg body weight). No mortality was observed which indicates a very low lethality of the tested extract.


Assuntos
Antioxidantes/análise , Eucalyptus/química , Extratos Vegetais/análise , Animais , Antioxidantes/toxicidade , Cromatografia Líquida de Alta Pressão , Egito , Ácido Elágico/análise , Feminino , Flavonoides/análise , Ácido Gálico/análise , Extratos Vegetais/toxicidade , Folhas de Planta/química , Ratos , Testes de Toxicidade
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