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1.
Molecules ; 28(22)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-38005182

RESUMO

A phytochemical investigation of the stems of the Arabian plant Artemisia sieberi afforded three new isochlorogenic acid derivatives, namely isochlorogenic acid A-3'-O-ß-glucopyranoside (1), isochlorogenic acid A-3'-O-ß-glucopyranoside methyl ester (2), and isochlorogenic acid C-3'-O-ß-glucopyranoside (3), obtained along with thirteen known secondary metabolites belonging to distinct structural classes. The structures of the new metabolites were elucidated by modern spectroscopic techniues based on high-resolution mass spectrometry (HR-ESIMS) and 1D/2D nuclear magnetic resonance (NMR). All isolated compounds were tested for their potential antimicrobial activity against four different bacterial strains (Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa), in addition to a fungal strain (Candida tropicalis), The results were expressed as the diameter of the clear zone (in millimetres) around each well. Compounds 1 and 3 (isochlorogenic acid A-3'-O-ß-glucopyranoside and isochlorogenic acid C-3'-O-ß-glucopyranoside, respectively) displayed remarkable antifungal effect and potent antibacterial activities against B. subtilis and S. aureus, respectively. 3α,4α-10ß-trihydroxy-8α-acetyloxyguaian-12,6α-olide (6) and angelicoidenol 2-O-ß-d-glucopyranoside (9) emerged as interesting dual antibacterial (selective on P. aeruginosa)/antifungal agents.


Assuntos
Artemisia , Plantas Medicinais , Plantas Medicinais/química , Glucosídeos/farmacologia , Glucosídeos/química , Staphylococcus aureus , Extratos Vegetais/química , Antibacterianos/química , Antifúngicos/farmacologia , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana
2.
Molecules ; 26(8)2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33920952

RESUMO

The increasing prevalence of microbial infections and the emergence of resistance to the currently available antimicrobial drugs urged the development of potent new chemical entities with eminent pharmacokinetic and/or pharmacodynamic profiles. Thus, a series of new indole-triazole conjugates 6a-u was designed and synthesized to be assessed as new antimicrobial candidates using the diameter of the inhibition zone and minimum inhibitory concentration assays against certain microbial strains. Their in vitro antibacterial evaluation revealed good to moderate activity against most of the tested Gram-negative strains with diameter of the inhibition zone (DIZ) values in the range of 11-15 mm and minimum inhibition concentration (MIC) values around 250 µg/mL. Meanwhile, their in vitro antifungal evaluation demonstrated a potent activity against Candida tropicalis with MIC value as low as 2 µg/mL for most of the tested compounds. Moreover, compound 6f is the most potent congener with an MIC value of 2 µg/mL against Candida albicans.


Assuntos
Antifúngicos/farmacologia , Indóis/química , Triazóis/química , Triazóis/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade , Triazóis/síntese química
3.
Indian J Biochem Biophys ; 52(2): 179-88, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26118130

RESUMO

Lipases are the enzymes of choice for laundry detergent industries, owing to their triglyceride removing ability from the soiled fabric, which eventually reduces the usage of phosphate-based chemical cleansers in the detergent formulation. In this study, a novel thermo-alkaline lipase-producing strain identified as Bacillus stearothermophilus was isolated from the soil samples of olive oil mill. Enhanced lipase production was observed at 55 degrees C, pH 11 and after 48 h of incubation. Among the substrates tested, xylose (a carbon source), peptone (a nitrogen source) and olive oil at a concentration of 1% were suitable substrates for enhancing lipase production. MgSO4 and Tween-80 were suitable substrates for maximizing lipase production. The enzyme was purified to homogeneity by a single CM-Sephadex column chromatography and revealed molecular mass of 67 kDa. The enzyme (BL1) was active over a wide range of pH from 9.0 to 13.0, with an optimum at pH 11.0, exhibited maximal activity at 55 degreesC and retained more than 70% of its activity after incubation at 70 degrees C or pH 13 for 0.5 h or 24 h, respectively. The enzyme hydrolyzed both short and long-chain triacylglycerols at comparable rates. BL1 was studied in a preliminary evaluation for use in detergent formulation solutions. This novel lipase showed extreme stability towards non-ionic and anionic surfactants after pre-incubation for 1 h at 40 degrees C, and good stability towards oxidizing agents. Additionally, the enzyme showed excellent stability and compatibility with various commercial detergents, suggesting its potential as an additive in detergent formulations.


Assuntos
Álcalis/metabolismo , Detergentes/metabolismo , Geobacillus stearothermophilus/enzimologia , Lipase/metabolismo , Estabilidade Enzimática
4.
Nat Prod Res ; : 1-8, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38733626

RESUMO

Plants contain many bioactive compounds with potent antibacterial and efflux pump inhibitory activity (EPI). In this study, gallic acid extracted from pomegranate molasses by analytical HPLC holds promise as an EPI drug for Staphylococcus aureus mediated tetracycline resistance, it lowered the bacterial resistance and reversed the mechanism via tet family efflux pump, using molecular technique and in-silico molecular docking analysis. Extracted gallic acid combined with tetracycline demonstrated a significant decrease in the minimal inhibitory concentration MIC compared to its single activity. Similarly, little growth and lower fluorescence of S. aureus were observed on ethidium bromide (2.5 mg/mL) agar plates, indicating a reversible efflux pump mechanism and a potent EPI activity. Molecular docking demonstrated a promising affinity binding energy between gallic acid and tet efflux genes, opening a new baseline in bacterial infection treatment. PCR for tetK and Qac A/B genes failed to show any relation between tet genes and gallic acid.

5.
Indian J Biochem Biophys ; 50(3): 186-95, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23898481

RESUMO

A phospholipase A2 belonging to IIA group secretory PLA2 was isolated and purified to homogeneity from the intestine of common stingray (Dasyatis pastinaca) using acidic treatment (pH 1.5) and ammonium sulphate precipitation methods combined with single-column ion-exchange chromatography. The purified enzyme was found to be a glycosylated monomeric protein with a molecular mass of about 14 kDa. The stingray sPLA2-IIA had optimum activity at 45 degrees C, unlike known mammalian PLA2-IIAs, which show optimum activity at 37 degrees C. The purified enzyme exhibited a specific activity of 290 U/mg at optimal conditions (pH 9.5 and 45 degrees C) in the presence of 6 mM NaDC and 8 mM CaCl2 with egg yolk as substrate. The NH2-terminal sequence of the enzyme and some protein fragments obtained from its tryptic digestion were also determined. All sequences obtained were similar to those of sPLA2-IIA. The enzyme also showed good stability in the presence of organic solvents, acidic and alkaline pH media and high temperature conditions. Thus, the purified enzyme exhibited a number of unique and promising properties, making it a potential possible candidate for future applications in the treatment of phospholipid-rich industrial effluents and synthesis of useful preparations for the food production and processing industry.


Assuntos
Elasmobrânquios/metabolismo , Fosfolipases A2 do Grupo II/química , Fosfolipases A2 do Grupo II/isolamento & purificação , Intestinos/enzimologia , Animais , Ativação Enzimática , Estabilidade Enzimática , Especificidade por Substrato
6.
Nutrients ; 15(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36678232

RESUMO

Obesity prevalence is rising globally, as are the number of chronic disorders connected with obesity, such as diabetes, non-alcoholic fatty liver disease, dyslipidemia, and hypertension. Bariatric surgery is also becoming more common, and it remains the most effective and long-term treatment for obesity. This study will assess the influence of Laparoscopic Sleeve Gastrectomy (LSG) on gut microbiota in people with obesity before and after surgery. The findings shed new light on the changes in gut microbiota in Saudi people with obesity following LSG. In conclusion, LSG may improve the metabolic profile, resulting in decreased fat mass and increased lean mass, as well as improving the microbial composition balance in the gastrointestinal tract, but this is still not equivalent to normal weight microbiology. A range of factors, including patient characteristics, geographic dispersion, type of operation, technique, and nutritional and caloric restriction, could explain differences in abundance between studies. This information could point to a novel and, most likely, tailored strategy in obesity therapy, which could eventually be incorporated into health evaluations and monitoring in preventive health care or clinical medicine.


Assuntos
Cirurgia Bariátrica , Microbioma Gastrointestinal , Laparoscopia , Obesidade Mórbida , Humanos , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Obesidade Mórbida/metabolismo , Obesidade/complicações , Obesidade/cirurgia , Cirurgia Bariátrica/métodos , Laparoscopia/métodos , Resultado do Tratamento
7.
Saudi J Biol Sci ; 29(4): 2532-2540, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35531156

RESUMO

Marine ecosystems are highly dependent on macroalgea in providing food and shelter for aquatic organisms, interacting with many bacteria and mostly producing secondary metabolites of potent therapeutic antibacterial property. Screening of marine microbial secondary metabolites of valuable biotechnological and therapeutical applications are now extensively studied. In this study, Bacillus spp. identified by DNA sequencing and found associated with Turbinaria ornata, was screened and characterized for its cell free supernatant (CFS) possible antimicrobial and antibiofilm applications. Among the 7 microbial isolates tested, CFS greatly affected Bacillus subitilis (12 mm) and inhibited equally the yeast isolates Candida albicans, Candida tropicalis and Candida glabrata (10 mm) and had no or negligible effect on S.aureus, E.coli, P. aeruginosa. As for the CFS antibiofilm activity, no difference was revealed from the positive control. Algal crude extracts (methanol, acetone and aqueous), on the other hand, were similarly tested for their antimicrobial activity against the seven microbial isolates, where highest activity was observed with the aqueous crude extract against Staphylococcus aureus(10 mm) and Pseudomonas aeruginosa (9 mm) compared to the negligible effects of methanol and acetone crude extracts. Chemical analysis was performed to reveal the major constituents of both crude algal extracts and Bacillus spp. CFS. FTIR spectrum of the bacterial CFS indicated the presence of bacteriocin as the major lipopeptide responsible for its biological activity. Whereas, methanol and water crude algal extract GC-MS spectra revealed different chemical groups of various combined therapeutical activity mainly Naphthalene, amino ethane-sulfonic acid, pyrlene, Biotin and mercury chloromethyl correspondingly. Thus, the present study, demonstrated the moderate activity of both crude algal extract and the bacterial CFS, however, further investigations are needed for a better biological activity.

8.
Saudi J Biol Sci ; 29(4): 2772-2781, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35531187

RESUMO

The green silver nanoparticles (green AgNPs) exhibit an exceptional antimicrobial property against different microbes, including bacteria and fungi. The current study aimed to compare the antifungal activities of both the crude aqueous extract of Portulaca oleracea or different preparations of green AgNPs biosynthesized by mixing that aqueous extract with silver nitrate (AgNO3). Two preparations of the green AgNPs were synthesized either by mixing the aqueous extract of P. oleracea with silver nitrate (AgNO3) (normal AgNPs) or either irradiation of the AgNPs, previously prepared, under 60Co γ-ray using chitosan (gamma-irradiated AgNPs). Characterization of different AgNPs were tested by Zeta potential analyzer, Ultraviolet (UV) Visible Spectroscopy, and Fourier-Transform Infrared (FTIR) spectrometry. Three different plant pathogenic fungi were tested, Curvularia spicifera, Macrophomina phaseolina, and Bipolaris sp. The antifungal activities were evaluated by Transmission Electron Microscope (TEM) for either the crude aqueous extract of P. oleracea at three doses (25%, 50%, and 100%) or the newly biosynthesized AgNPs, normal or gamma-irradiated. With a few exceptions, the comparative analysis revealed that the irradiated green AgNPs at all three concentrations showed a relatively stronger antifungal effect than the normal AgNPs against all the three selected fungal strains. UV-visible spectroscopy of both preparations showed surface plasmon resonance at 421 nm. TEM results showed that both AgNPs were aggregated and characterized by a unique spherical shape, however, the gamma-irradiated AgNPs were smaller than the non-irradiated AgNPs (0.007-0.026 µM vs. 0.009-0.086 µM). TEM photographs of the fungal strains treated with the two AgNPs preparations showed flaccid structures, condensed hyphae, and shrunken surface compared with control cells. The data suggested that the biosynthesized P. oleracea AgNPs have antifungal properties against C. spicifera, M. phaseolina, and Bipolaris sp. These AgNPs may be considered a fungicide to protect different plants against phytopathogenic fungi.

9.
Gut Pathog ; 13(1): 54, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34517895

RESUMO

BACKGROUND: Innovative research highlighted the probable connection between autism spectrum disorder (ASD) and gut microbiota as many autistic individuals have gastrointestinal problems as co-morbidities. This review emphasizes the role of altered gut microbiota observed frequently in autistic patients, and the mechanisms through which such alterations may trigger leaky gut. MAIN BODY: Different bacterial metabolite levels in the blood and urine of autistic children, such as short-chain fatty acids, lipopolysaccharides, beta-cresol, and bacterial toxins, were reviewed. Moreover, the importance of selected proteins, among which are calprotectin, zonulin, and lysozyme, were discussed as biomarkers for the early detection of leaky gut as an etiological mechanism of ASD through the less integrative gut-blood-brain barriers. Disrupted gut-blood-brain barriers can explain the leakage of bacterial metabolites in these patients. CONCLUSION: Although the cause-to-effect relationship between ASD and altered gut microbiota is not yet well understood, this review shows that with the consumption of specific diets, definite probiotics may represent a noninvasive tool to reestablish healthy gut microbiota and stimulate gut health. The diagnostic and therapeutic value of intestinal proteins and bacterial-derived compounds as new possible biomarkers, as well as potential therapeutic targets, are discussed.

10.
PLoS One ; 15(8): e0237567, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32797097

RESUMO

Distinct morphological MgO nanoparticles (MgONPs) were synthesized using biomasses of Saussurea costus roots. The biomass of two varieties of Saussurea costus (Qustal hindi and Qustal bahri) were used in the green synthesis of MgONPs. The physical and chemical features of nanoparticles were confirmed by spectroscopic and microscopic techniques. The surface morphology of the obtained nanoparticles was detected at different magnifications by SEM and TEM microscopy and the size of nanoparticles were found to be 30 and 34 nm for Qustal hindi and Qustal bahri, respectively. The antimicrobial activity of the prepared MgONPs was screened against six pathogenic strains. The synthesized nanoparticles by Qustal bahri biomass exerted significant inhibition zones 15, 16, 18, 17, 14, and 10 mm against E. coli, P. aeruginosa, C. tropicalis and C. glabrata, S. aureus and B. subtilis as compared to those from Qustal hindi 12, 8 and 17 mm against B. subtilis, E. coli and C. tropicalis, respectively. MgONPs showed a potential cytotoxicity effect against MCF-7 breast cancer cell lines. Cellular investigations of MgONPs revealed that the prepared nanoparticles by Qustal bahri exhibited high cytotoxicity against MCF-7 cancer cell lines. IC50 values in MCF-7 cells were found to be 67.3% and 52.1% for MgONPs of Saussurea costus biomasses, respectively. Also, the photocatalytic activity of MgONPs of each Saussurea costus variety was comparatively studied. They exhibited an enhanced photocatalytic degradation of methylene blue after UV irradiation for 1 h as 92% and 59% for those prepared by Qustal bahri and Qustal hindi, respectively. Outcome of results revealed that the biosynthesized MgONPs showed promising biomedical potentials.


Assuntos
Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Óxido de Magnésio/farmacologia , Azul de Metileno/química , Saussurea/química , Anti-Infecciosos/química , Antineoplásicos/química , Bactérias/efeitos dos fármacos , Biomassa , Catálise , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Fungos/efeitos dos fármacos , Química Verde , Humanos , Células MCF-7 , Óxido de Magnésio/química , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Processos Fotoquímicos , Extratos Vegetais/química , Raízes de Plantas/química
11.
Saudi J Biol Sci ; 25(3): 409-417, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29686504

RESUMO

An extracellular lipase of a newly isolated S. aureus strain ALA1 (SAL4) was purified from the optimized culture medium. The SAL4 specific activity determined at 60 °C and pH 12 by using olive oil emulsion or TC4, reached 7215 U/mg and 2484 U/mg, respectively. The 38 NH2-terminal amino acid sequence of the purified enzyme starting with two extra amino acid residues (LK) was similar to known staphylococcal lipase sequences. This novel lipase maintained almost 100% and 75% of its full activity in a pH range of 4.0-12 after a 24 h incubation or after 0.5 h treatment at 70 °C, respectively. Interestingly, SAL4 displayed appreciable stability toward oxidizing agents, anionic and non-ionic surfactants in addition to its compatibility with several commercial detergents. Overall, these interesting characteristics make this new lipase promising for its application in detergent industry.

12.
J Mol Neurosci ; 66(3): 403-413, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30284229

RESUMO

Metabolites of proper fatty acids modulate the inflammatory response and are essential for normal brain development; equally, abnormal fatty acid metabolism plays a critical role in the pathology of autism. Currently, dietary supplements are often used to improve the core symptoms of Autism spectrum disorder (ASD). The present study analyzed the effects of orally supplemented omega-3 (ω-3) and vitamin B12 on ameliorating oxidative stress and impaired lipid metabolism in a propionic acid (PPA)-induced rodent model of autism, together with their effect on the gut microbial composition, where great fluctuations in the bacterial number and strains were observed; interestingly, polyunsaturated fatty acids such as omega-3 induced higher growth of the gram-positive bacterium Staphylococcus aureus and decreased the survival rates of Clostridia sp. as well as other enteric bacterial strains. Thirty-five young male western albino rats were divided into five equal groups. The first group served as the control; the second group was given an oral neurotoxic dose of PPA (250 mg/kg body weight/day) for 3 days. The third group received an oral dose of ω-3 (200 mg/kg body weight/day) for 30 days after the 3-day PPA treatment. Group four was given an oral dose of vitamin B12 (16.7 mg/kg/day) for 30 days after PPA treatment. Finally, group five was given a combination of both ω-3 and vitamin B12 at the same dose for the same duration after PPA treatment. Biochemical parameters related to oxidative stress and impaired fatty acid metabolism were investigated in the brain homogenates of each group. The effects of the dietary supplements on the gut microbiota were also observed. The PPA-treated autistic model expressed significantly higher levels of lipid peroxides and 5-lipoxygenase (5-LOX) and significantly less glutathione (GSH), glutathione S-transferase (GST), and cyclooxygenase 2 (COX2) than the control group. However, a remarkable amelioration of most of the impaired markers was observed with oral supplementation with ω-3 and vitamin B12, either alone or in combination. Our results concluded that impairment at various steps of the lipid metabolic pathways may contribute to the development of autism; however, supplementation with ω-3 and vitamin B12 can result in a positive therapeutic effect.


Assuntos
Antioxidantes/uso terapêutico , Transtorno Autístico/prevenção & controle , Ácidos Graxos Ômega-3/uso terapêutico , Vitamina B 12/uso terapêutico , Vitaminas/uso terapêutico , Animais , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Transtorno Autístico/etiologia , Transtorno Autístico/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Ômega-3/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Metabolismo dos Lipídeos , Masculino , Propionatos/toxicidade , Ratos , Vitamina B 12/administração & dosagem , Vitamina B 12/farmacologia , Vitaminas/administração & dosagem , Vitaminas/farmacologia
13.
3 Biotech ; 7(2): 148, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28597160

RESUMO

Protease inhibitors from plants are well known to be potent inhibitors of the growth of bacteria, fungi, and even certain viruses which make them excellent candidates for use as the lead compounds for the development of novel antimicrobial agents for applications in medicine. In this study, Rhamnus frangula was selected as a protease inhibitor source. The maximum recovery of the protease inhibitor against trypsin was recorded in the crude extract made in 0.1 M phosphate buffer (pH 7.0) and isolated from the mature leaves. Then, the protease inhibitor designated as RfIP1 was purified to homogeneity by Sephadex G50 with an apparent molecular mass of 22.5 kDa and its N-terminal sequence exhibited a high degree of homology with known serine protease inhibitor sequences. The RfIP1 displayed maximal activity at pH 7 and 37 °C. It maintained almost 80% of its maximal activity through a large pH range. The thermo-stability of RfIP1 was markedly enhanced by BSA, CaCl2, and sorbitol, whereas the addition of Mg2+, Zn2+, NaTDC, SDS, DTT, and ß-ME significantly promoted inhibitory activity. The protease inhibitor displayed high inhibitory activity toward some known proteases (cathepsin B, chymotrypsin, collagenase, thrombin, and trypsin) that have more importance in pharmaceutical industry and it acted as potent inhibitor of some commercially proteases from Aspergillus oryzae, Bacillus sp, and Bacillus licheniformis. The protease inhibitor also possessed an appreciable antibacterial effect against both Gram-positive and Gram-negative bacteria.

14.
Saudi J Biol Sci ; 24(1): 162-169, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28053587

RESUMO

The present study demonstrates the antibacterial activity of selected brown and green marine algae collected from Saudi Arabia Red Sea and Arabian Gulf. The methanolic and acetone extracts were tested against gram positive, gram negative bacteria and Candida albicans in an attempt to be used as an alternative to commonly used antibiotics. Both brown seaweed species Sargassum latifolium B and Sargassum platycarpum A methanolic extracts were found to be active against gram positive than gram negative; however, S. latifolium acetone extract gave the highest inhibitory activity against Salmonella sp. On the other hand, Cladophorasocialis organic extract demonstrated higher antibacterial activity than the fresh extract but both C. socialis extracts revealed decreased activity compared to Sargassum extracts. Cladophora methanolic extract showed an obvious effect on methicillin resistant Staphylococcus aureus (MRSA). The present work shows a comparable therapeutic potency of the tested seaweed members Sargassum and Cladophora extracts in treating human microbial pathogens to synthetic chemical antibiotics. A remarkable higher antioxidant DPPH free radical scavenging effect was recorded with Sargassum sp. compared to Cladophora sp. FTIR Infrared Spectrometer analysis together with the high performance liquid chromatography provided a detailed description of the possible functional constituents and the major chemical components present in marine macroalgae particularly in brown seaweeds to be mainly of phenolic nature to which the potent antimicrobial activity is being attributed.

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