Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 32
Filtrar
1.
Mol Divers ; 27(1): 543-569, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35449388

RESUMO

Well-known Betti bases are the products obtained by the one-pot multicomponent reaction of 1-naphthol/2-naphthol, aliphatic/aromatic aldehydes, and secondary amines, and this reaction is known as the Betti reaction. During recent years, due to the unveiling of the pharmacological and synthetic potential of Betti bases, a tremendous increase in the studies reporting novel synthetic methods for the efficient synthesis of Betti bases was observed. This review presents the recent key developments in the green synthesis of the Betti bases and accounts for the significant number of the literature reported during 2019-2022. Both catalyst free as well as the catalyst promoted synthesis (nanocatalyst, biocatalyst, transition metal catalyst, etc.) along with the synthetic applications (catalyst, ligands/chiral auxiliaries, and valuable synthons), optoelectronic applications (fluorescence sensors for phosgene gas, Hg2+, and Cr3+ detection, quasi-reversible redox potential) and biological properties (anticancer agents, antioxidant, anti-inflammatory agents, antitubercular agents, pesticidal agents, anti-Alzheimer agents, Topoisomerase I inhibitors, YAP-TEAD interaction inhibitors, and DNA binding and cleavage activity) are discussed. There is a surge of interest for the development of the green and efficient Betti reaction for the construction of C-C and C-N bond in a single-step reaction accessing Betti bases as products. Along with key methodological developments for the green synthesis of Betti bases, their applications in synthetic organic chemistry, optoelectronic sensors, advanced materials synthesis, agrochemicals and pharmaceutically active scaffolds, during the period of 2019-2022, have been considered.


Assuntos
Aldeídos , Aminas , Naftóis , Aminas/química , Catálise , Aldeídos/química , Naftóis/química
2.
Curr Microbiol ; 80(3): 99, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36745203

RESUMO

An indigenous chromate-resistant bacterial strain isolated from tannery effluent was identified based on morphological, biochemical, and 16S rRNA gene sequencing, as Enterobacter cloacae UT25. It was found to resist heavy metal ions such as Cr (VI), Pb (II), Cu (II), Co (II), Ni (II), Hg (II), and Zn (II) and antibiotics. The strain was able to remove 89 and 86% chromate, after 24 h of incubation in a Luria-Bertani (LB) medium at an initial Cr (VI) concentration of 1000 and 1500 µg/ml, respectively. Minimum inhibitory concentration (MIC) was observed for chromate to be 80,000 and 1850 µg/ml, after 48 h of incubation in LB and acetate minimal media (AMM), respectively. Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) analysis showed discrete cells with intact and smooth cell walls and homogenous cytoplasm in the absence of metal stress, whereas chromate stress caused cell lysis and reduction in size, which was a characteristic response to Cr (VI) toxicity. Energy Dispersive X-Ray Spectroscopy (EDX) confirmed the adsorption of oxyanions to the cell wall which was one of the Cr (VI) removal mechanisms by the bacterium. Atomic Force Microscopy (AFM) micrographs of chromate-untreated and treated cells revealed Root Mean Square roughness (Rq) values of 16.25 and 11.26 nm, respectively, indicating less roughness in the presence of stress. The partial gene sequence of class 1 integrons (intI1) of strain UT25 showed 94% homology with intI1 gene of strain Enterobacter hormaechei strain ECC59 plasmid pECC59-1. The present analysis highlighted the potential of E. cloacae UT25 as a promissory bacterium that could be applied in removing chromate from polluted environments.


Assuntos
Cromatos , Metais Pesados , Cromo , Enterobacter cloacae/genética , RNA Ribossômico 16S/genética , Metais Pesados/toxicidade , Bactérias/genética , Biodegradação Ambiental
3.
Arch Microbiol ; 202(7): 1907-1913, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32448962

RESUMO

In this work, volatile fatty acids (VFAs) were used as a carbon source to assess the ability of bacteria present in waste activated sludge (WAS), as indigenous flora, to accumulate polyhydroxyalkanoates (PHA). Acetic acid and propionic acid were used both separately and in combination as feedstock, producing either homopolymer poly(3-hydroxybutyrate) (3PHB) and/or the co-polymer, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) P(3HB-co-3HV). The overall potential to use waste activated sludge as biomass for production of valuable polymers was assessed, and a quality assessment of the as-produced polymers was run, with the extracted polymer being analyzed for properties such as thermal, microstructure and molecular weight. It was found that a blend of copolymers was typically produced, with thermal properties being similar to those reported elsewhere. The overall PHA cell content obtained was 0.29 gPHA gVSS-1.


Assuntos
Biomassa , Microbiologia Industrial , Poli-Hidroxialcanoatos/metabolismo , Esgotos/microbiologia , Carbono/metabolismo , Ácidos Graxos Voláteis , Peso Molecular , Poli-Hidroxialcanoatos/biossíntese , Poli-Hidroxialcanoatos/química
4.
J Basic Microbiol ; 58(3): 247-254, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29314110

RESUMO

Mixed bacterial cultures are increasingly being used in the production of polyhydroxyalkanoates (PHAs), as they have the potential to be more cost effective than axenic pure cultures. The purpose of this study was to use pure cultures in combination to identify their potential of PHA production. In this work we used volatile fatty acids (VFAs) and glucose as carbon source to check the ability of selected strains ST2 (Pseudomonas sp.) and CS8 (Bacillus sp.) as co-culture. The production of PHA in pure co-cultures of bacteria was therefore investigated in order to understand the effect of combining cultures on PHA production parameters and material properties. Bacteria could use the feed in better way when mixed as compared to individual strain. In undertaking this analysis, model volatile fatty acids (i.e., acetic and propionic acids) were used alone and in combination with glucose as feedstock. The production by Pseudomonas was 34% while 24% by Bacillus. However when combined and mixed feed (glucose + propionic acid) was used, 35% PHA produced. Overall, it was found that the ability of the pure cultures to produce PHA was low but when selected cultures were mixed, their ability to produce PHA was enhanced. Copolymers were obtained instead of homopolymers with improved properties. This suggests that industrial wastewater rich in volatile fatty acids and carbohydrates can be a good carbon source for PHA production with variable properties.


Assuntos
Bacillus/metabolismo , Carbono/metabolismo , Ácidos Graxos Voláteis/metabolismo , Glucose/metabolismo , Poli-Hidroxialcanoatos/metabolismo , Pseudomonas/metabolismo , Bacillus/crescimento & desenvolvimento , Técnicas de Cocultura , Pseudomonas/crescimento & desenvolvimento
5.
Pak J Pharm Sci ; 31(3): 919-926, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29716874

RESUMO

Bacterial strains, Bacillus cereus Lb (KF011486), Brevundimonas sp. A2 (JX996070), Bacillus cereus AZS and Bacillus sp. 11A, isolated from soil sample, were checked for their antimicrobial property against Bacillus as test organism. The bactericidal effect of the antagonistic strains against test organism was found to be at 1280, 1280, 40 and 160 arbitrary units (AU/ml), respectively. The Crude Antimicrobial Compound (CAC) had a bactericidal effect on target cell by degeneration of its cell wall. The chemical analysis of TLC purified extract of intracellular and extracellular antimicrobial compound produced by Bacillus cereus Lb by GC-MS analysis revealed the presence of organic compounds such as acetic acid and certain volatile organic substances such as, toluene, 2-butanone, etc., with antimicrobial property. N-acetylmuramoyl-L-alanine amidase is a cell wall hydrolysing enzyme and involved in cell wall degeneration of the target cells. These volatile organic compounds help this enzyme by decreasing the pH of the environment hence maximizing the amidase activity which possesses maximum activity at pH range of 5.5-6.5.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Bacillus cereus/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microbiologia do Solo , Antibacterianos/química , Bacillus/efeitos dos fármacos , Bacillus/fisiologia , Bacillus cereus/fisiologia , Cromatografia em Camada Fina/métodos
6.
Pak J Pharm Sci ; 31(2): 499-507, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29618441

RESUMO

Utilization of herbs for medicinal purpose started in the early history of mankind several thousand years ago. In this study, some plants that are used for lowering cholesterol level in local areas of Pakistan, such as Artemisia absinthium L., Swertia chirayita and Sphaeranthus indicus were screened for their phytochemical and antibacterial properties. For this purpose, these plants were extracted in different solvents i.e. ethanol, hexane and ethyl acetate. Phytochemcial analysis unveiled the existence of different bioactive compounds in these extracts. Presence of sugars was further confirmed by performing TLC. Antibacterial activity was determined against indicated bacterial strains, among all extracts Gul-e-mundi had maximum inhibition zone (23mm). DPPH free radical assay revealed the significant antioxidative potential of all the extracts where Gul-e-mundi showed maximum potential i.e., 83%. Plant extracts were also showing anti-proliferative activity on root tips of Allium cepa and Gul-e-mundi was observed to have maximum antimitotic activity i.e. 5%. GC-MS analysis revealed that oleic acid and linoleic acid were the compounds responsible for imparting antibacterial potential to Gul-e-mundi. In conclusion, among all the tested extracts Gul-e-mundi had maximum antibacterial, antioxidative and antimitotic potential. For future studies, phytochemcials responsible for these activities can be isolated and modified for pharmacological purpose.


Assuntos
Antibacterianos/farmacologia , Artemisia absinthium/química , Asteraceae/química , Compostos Fitoquímicos/análise , Swertia/química , Antibacterianos/química , Antioxidantes/farmacologia , Cromatografia em Camada Fina , Avaliação Pré-Clínica de Medicamentos , Cromatografia Gasosa-Espectrometria de Massas , Cebolas/efeitos dos fármacos , Paquistão , Extratos Vegetais/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química
7.
Artigo em Inglês | MEDLINE | ID: mdl-29641883

RESUMO

Tuberculosis (TB) is a cause of death from a single infectious agent Mycobacterium tuberculosis (MTB), leading to approximately 2.5 million deaths annually worldwide. Information regarding prevalence and pattern of drug resistance among TB patients in Pakistan remains inadequate due to the country's limited resources. This study compared conventional diagnostic techniques with a PCRbased assay targeting IS6110 sequence. In addition, MTB drug resistant profiles against four first-line drugs (ethambutol, isoniazid, rifampin, and streptomycin) from new and retreatment cases of TB. From 101 sputum samples microscopic examination of Ziehl-Neelsen-stained smears and culturing on Lowenstein Jensen medium resulted in 96% and 100% positives, compared to 98% by PCR. Prevalence of MDR-MTB was 41.5% and 58.5% among new (n = 51) and retreatment (n = 50) cases, but 10% of the former group were sensitive to all four first-line anti-TB drugs. Thus, MDR-MTB is highly prevalent among TB patients in Punjab Province, Pakistan (where the study was conducted) and, although PCR amplification of MTB-specific IS6110 sequence was rapid, it lacked the sensitivity of the culture assay.


Assuntos
Antituberculosos/uso terapêutico , Testes Diagnósticos de Rotina/métodos , Farmacorresistência Bacteriana Múltipla , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana/métodos , Pessoa de Meia-Idade , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/genética , Paquistão , Reação em Cadeia da Polimerase/métodos , Adulto Jovem
8.
J Sci Food Agric ; 97(7): 1997-2006, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28093767

RESUMO

Increasing the sunflower seed oil content as well as improving its quality makes it compatible for industrial demands. This is an important breeding objective of sunflower which increases its market value and ensures high returns for the producers. The present review focuses on determining the progress of improving sunflower seed oil content and modifying its quality by empirical and advanced molecular breeding methods. It is known that the sunflower oil content and quality have been altered through empirical selection methods and mutation breeding programmes in various parts of the world. Further improvement in seed oil content and its components (such as phytosterols, tocopherols and modified fatty acid profile) has been slowed down due to low genetic variation in elite germplasm and complex of hereditary traits. Introgression from wild species can be carried out to modify the fatty acids profile and tocopherol contents with linkage drags. Different transgenes introduced through biotechnological methods may produce novel long-chain fatty acids within sunflower oil. Bio-engineering of sunflower oil could allow it to be used in diverse industrial products such as bio-diesel or bio-plastics. These results showed that past and current trends of modifying sunflower oil quality are essential for its further expansion as an oilseed crop. © 2017 Society of Chemical Industry.


Assuntos
Helianthus/química , Óleos de Plantas/química , Cruzamento , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Helianthus/genética , Helianthus/metabolismo , Óleos de Plantas/metabolismo , Sementes/química , Sementes/genética , Sementes/metabolismo , Óleo de Girassol
9.
J Basic Microbiol ; 55(9): 1064-74, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25871833

RESUMO

Indigenous Cr(VI) reducing bacterial strains Pseudomonas aeruginosa Rb-1 and Ochrobactrum intermedium Rb-2 were evaluated for EPS production under Cr(VI) challenged and free conditions. Strain Rb-2 was more efficient in total EPS production (13.63 mg g(-1)) than Rb-1 (4.15 mg g(-1)) under Cr(VI) stress. Thick covering of capsular material around the cells of both bacterial strains was detected by electron microscopy. Transmission electron micrographs showed the appearance of pilli like structures under chromium stress by two bacteria suggested the possible involvement of this in exchange of hereditary material to increase their chances of survival under stress conditions. FTIR study showed involvement of sulphonate and hydroxyl groups in the binding with Cr(VI) ions. Solid-state (13) C NMR spectra revealed that EPS produced by both strains exhibited structural similarity with the glucan. The partial psl gene sequences of Rb-1 and Rb-2 showed homology with psl gene of Pseudomonas aeruginosa PAO1 and capsular polysaccharide biosynthesis protein of various strains of Pseudomonas. This is the first report on the identification of psl gene from Ochrobacterum in NCBI GenBank database up to our knowledge.


Assuntos
Biopolímeros/biossíntese , Cromo/metabolismo , Resíduos Industriais , Ochrobactrum/metabolismo , Pseudomonas aeruginosa/metabolismo , Águas Residuárias/microbiologia , Biopolímeros/metabolismo , Genes Bacterianos , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Ochrobactrum/isolamento & purificação , Pseudomonas aeruginosa/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Águas Residuárias/química
10.
Prep Biochem Biotechnol ; 44(8): 822-33, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24279753

RESUMO

To decrease the polyhydroxyalkanoate (PHA) production cost by supplying renewable carbon sources has been an important aspect in terms of commercializing this biodegradable polymer. The production of biodegradable poly(3-hydroxyalkanoates) (PHA) from raw potato starch by the Bacillus cereus 64-INS strain isolated from domestic sludge has been studied in a lab-scale fermenter. The bacterium was screened for the degradation of raw potato starch by a starch hydrolysis method and for PHA production by Nile blue A and Sudan black B staining. Shake-flask cultures of the bacterium with glucose [2% (w/v)] or raw potato starch [2% (w/v)] produced PHA of 64.35% and 34.68% of dry cell weight (DCW), respectively. PHA production was also carried out in a 5-L fermenter under control conditions that produced 2.78 g/L of PHA and PHA content of 60.53% after 21 hr of fermentation using potato starch as the sole carbon source. Gas chromatography-mass spectroscopy (GC-MS) analyses confirmed that the extracted PHA contained poly(3-hydroxybutyrate) (PHB) as its major constituent (>99.99%) irrespective of the carbon source used. The article describes, for what we believe to be the first time, PHB production being carried out without any enzymatic or chemical treatment of potato starch at higher levels by fermentation. More work is required to optimize the PHB yield with respect to starch feeding strategies.


Assuntos
Bacillus cereus/metabolismo , Hidroxibutiratos/metabolismo , Microbiologia Industrial/métodos , Poliésteres/metabolismo , Solanum tuberosum/química , Amido/metabolismo , Reatores Biológicos/microbiologia , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Hidrólise , Hidroxibutiratos/química , Microbiologia Industrial/economia , Poliésteres/química , Esgotos/microbiologia , Amido/isolamento & purificação
11.
Data Brief ; 52: 109963, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38186739

RESUMO

Cemetery soils most likely contain degradative bacteria which possibly have beneficial potencies. However, the bacterial exploration in these potencies is still limitedly conducted in Indonesia. The raw sequence data of total bacteria in the cemetery soils through metagenomic analysis have been revealed. The data were obtained by collecting soil samples from six spots of two major Cemetery areas, which were Pracimaloyo (P) and Bonoloyo (B), in Surakarta City, Central Java, Indonesia. The six sample spots consisted of two samples from P area with respectively 20 cm and 140 cm depths and four samples of each two samples from B area with 20 and 40 cm depths. The total DNA was subsequently extracted from the collected soils using ZymoBIOMICS DNA Miniprep Kit. The total DNA then was amplified using a couple of 16S rRNA primers through Illumina HiSeq 2500 PE250 (Novogen, Korea) environment system. The raw sequence data has been submitted to the National Center for Biotechnology Information (NCBI) with project ID PRJNA997385. The archived sequence can be accessed in the NCBI website with the following URLs https://www.ncbi.nlm.nih.gov/sra/PRJNA997385. A brief analysis of the sequence data showed that the most common phyla in 20 cm-depths were Proteobacteria (29.5%), Actinobacteria (21.6%), and Firmicutes (19.2%), while Actinobacteria were the most found in 140 cm-depths with 34.2% followed by Proteobacteria (21.9%) and Firmicutes (16.6%). This data would be the first report of total bacterial sequence from cemetery soils in Indonesia.

12.
J Infect Public Health ; 16(10): 1544-1555, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37566991

RESUMO

BACKGROUND: The SARS-CoV-2 pandemic, caused by the novel coronavirus, has posed a significant global health threat since its emergence in late 2019. The World Health Organization declared the outbreak a pandemic on March 11, 2020, due to its rapid global spread and impact on public health. New variants have raised concerns about their potential impact on the transmission of the virus and the effectiveness of current diagnostic tools, treatments, and vaccines. This study aims to investigate the effect of new variants in Pakistani virus strains on human receptors, specifically ACE2 and NRP1. In-silico analysis provides a powerful tool to analyze the potential impact of new variants on protein structure, function, and interactions. OBJECTIVES: The SARS-CoV-2 virus is evolving quickly. After being exposed in Wuhan, SARS-CoV-2 underwent numerous mutations, leading to several variants' emergence. These variants stabilize the interaction of spike protein with human receptors ACE2 and NRP1. The study aims to check the molecular effect of these variants on human receptors using the in-silico approach. MATERIAL AND METHODS: We use in-silico mutational tools to analyze new variants in SARS-CoV-2 and to check the molecular interaction of spike protein with human receptors (ACE2 and NRP1). Genomic sequences of 41 SARS-CoV-2 strains were sequenced using Ion Torrent (NGS) and submitted to the GISAID database. Spike protein of SARS-CoV-2 sequence trimmed and translated into a protein sequence using ExPasy. We used multiple sequence alignments to check for variants in the spike protein of strains. We utilized mutation tools such as Mupro, SIFT, SNAP2, and Mutpred2.3D structures of SARS-CoV-2 spike proteins (wild and mutated) to analyze further the mutations, ACE2 and NRP1 modelled by the ITASSER protein modelling server. Interactions of spike proteins (wild and mutant) analyzed by MD Docking, Simulation, and MMGBSA RESULTS: Variants I210T, V213G, S371F, S373P, T478K, F486V, Y505H, and D796Y were identified in SARS-CoV-2 Pakistani strains' spike protein. Variant Y505H were found to affect protein function. MD Docking, MMGBSA and MD simulation revealed that these variants increased spike protein's binding affinity with human receptors (ACE2 and NRP1). MD simulation revealed that mutated spike protein stabilized earlier than wild when interacting with ACE2 after 40 ns and interaction with NRP1 stabilized after 30 ns for mutated spike protein compared to wild. CONCLUSION: These variants in Pakistani strains of SARS-CoV-2 are increasing the stability of spike protein with human receptors. These findings provide insight into how the SARS-CoV-2 virus evolves and adapts to human hosts. This information may help develop strategies to control the virus's spread and develop effective treatments and vaccines in the future.


Assuntos
COVID-19 , Simulação de Dinâmica Molecular , Humanos , RNA Viral , Glicoproteína da Espícula de Coronavírus/genética , Enzima de Conversão de Angiotensina 2 , SARS-CoV-2/genética , Ligação Proteica , Mutação
13.
Polymers (Basel) ; 14(11)2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35683947

RESUMO

Polyethylene and Polyester materials are resistant to degradation and a significant source of microplastics pollution, which is an emerging concern. In the present study, the potential of a dumped site bacterial community was evaluated. After primary screening, it was observed that 68.5% were linear low-density polyethylene, 33.3% were high-density, and 12.9% were Polyester degraders. Five strains were chosen for secondary screening, in which they were monitored by FTIR, SEM and weight loss degradation trials. Major results were observed for Alcaligenes faecalis (MK517568) and Bacillus cereus (MK517567), as they showed the highest degradation activity. Alcaligenes faecalis (MK517568) degrades LLDPE by 3.5%, HDPE by 5.8% and Polyester by 17.3%. Bacillus cereus (MK517567) is better tolerated at 30 °C and degrades Polyester by 29%. Changes in infrared spectra indicated degradation pathways of different strains depending on the types of plastics targeted. Through SEM analysis, groves, piths and holes were observed on the surface. These findings suggest that soil bacteria develop an effective mechanism for degradation of microplastics and beads that enables them to utilize plastics as a source of energy without the need for pre-treatments, which highlights the importance of these soil bacteria for the future of effective plastic waste management in a soil environment.

14.
Infect Drug Resist ; 15: 5715-5728, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36199818

RESUMO

Introduction: Wastewaters carrying thousands of human specimens from the community and representing the diversity of antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs) directly from the community mirror the extent of AR spread in the community and environment. This study aimed to investigate the occurrence and distribution of antibiotic-resistant ESKAPEE bacteria in the community versus clinical settings through monitoring nonclinical and clinical wastewaters. Methodology: Seven wastewater samples were collected from different environmental sources. Isolates were obtained on general and selective media, biochemically characterized and antimicrobial-susceptibility tests performed by disk diffusion against 13 antibiotics according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines using MastDisc disk cartridges, and 16S rRNA metagenomic analysis was performed for two water samples. Results: Of 43 isolates, all representatives of the ESKAPEE group were recovered from clinical wastewaters, but Gram-positive cocci were not obtained from nonclinical wastewaters. The most predominant isolate was Pseudomonas aeruginosa (n=15; 33%), followed by Escherichia coli (n=9; 20%). Complete (100%) resistance to eleven of the tested antibiotics was observed, with only a few isolates being susceptible to clarithromycin, amikacin, and gentamicin. The lowest (79%) resistance rate was observed for linezolid. The multiple antibiotic resistance (MAR) index was calculated, and the resistance phenotype was independent of the wastewater source, indicated by x 2 (P=0.766). Metagenomic analysis replicated the results, as Pseudomonas spp., Acinetobacter spp., and Escherichia spp. were found to be predominant. The integrase gene (IntI1) was also amplified in Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Conclusion: Wastewaters are significant carriers of drug-resistant ESKAPEE bacteria and play an important role in their dissemination. This study endorses the periodic surveillance of water systems to evaluate the presence and burden of antibiotic-resistant pathogens.

15.
Polymers (Basel) ; 14(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36433088

RESUMO

The focus of the current study was the use of sewage wastewater to obtain PHA from a co-culture to produce a sustainable polymer. Two halotolerant bacteria, Bacillus halotolerans 14SM (MZ801771) and Bacillus aryabhattai WK31 (MT453992), were grown in a consortium to produce PHA. Sewage wastewater (SWW) was used to produce PHA, and glucose was used as a reference substrate to compare the growth and PHA production parameters. Both bacterial strains produced PHA in monoculture, but a copolymer was obtained when the co-cultures were used. The co-culture accumulated a maximum of 54% after 24 h of incubation in 10% SWW. The intracellular granules indicated the presence of nucleation sites for granule initiation. The average granule size was recorded to be 231 nm; micrographs also indicated the presence of extracellular polymers and granule-associated proteins. Fourier transform infrared spectroscopy (FTIR) analysis of the polymer produced by the consortium showed a significant peak at 1731 cm-1, representing the C=O group. FTIR also presented peaks in the region of 2800 cm-1 to 2900 cm-1, indicating C-C stretching. Proton nuclear magnetic resonance (1HNMR) of the pure polymer indicated chemical shifts resulting from the proton of hydroxy valerate and hydroxybutyrate, confirming the production of poly(3-hydroxybutyrate-co-3-hydroxy valerate) (P3HBV). A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay showed that the copolymer was biocompatible, even at a high concentration of 5000 µg mL-1. The results of this study show that bacterial strains WK31 and 14SM can be used to synthesize a copolymer of butyrate and valerate using the volatile fatty acids present in the SWW, such as propionic acid or pentanoic acid. P3HBV can also be used to provide an extracellular matrix for cell-line growth without causing any cytotoxic effects.

16.
Pharmaceutics ; 14(12)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36559258

RESUMO

It is important to create new generations of materials that can destroy multidrug-resistant bacterial strains, which are a serious public health concern. This study focused on the biosynthesis of an essential oil entrapped in titanium dioxide (TiO2) calcium alginate-based microspheres. In this research, calcium alginate-based microspheres with entrapped TiO2 nanoparticles and cinnamon essential oil (CI-TiO2-MSs) were synthesized, using an aqueous extract of Nigella sativa seeds for TiO2 nanoparticle preparation, and the ionotropic gelation method for microsphere preparation. The microspheres obtained were spherical, uniformly sized, microporous, and rough surfaced, and they were fully loaded with cinnamon essential oil and TiO2 nanoparticles. The synthesized microspheres were analyzed for antibacterial activity against the clinical multidrug-resistant strain of Staphylococcus aureus. Disc diffusion and flow cytometry analysis revealed strong antibacterial activity by CI-TiO2-MSs. The synthesized CI-TiO2-MSs were characterized by the SEM/EDX, X-ray diffraction, and FTIR techniques. Results showed that the TiO2 nanoparticles were spherical and 99 to 150 nm in size, whereas the CI-TiO2-MSs were spherical and rough surfaced. Apoptosis analysis and SEM micrography revealed that the CI-TiO2-MSs had strong bactericidal activity against S. aureus. The in vitro antibacterial experiments proved that the encapsulated CI-TiO2-MSs had strong potential for use as a prolonged controlled release system against multidrug-resistant clinical S. aureus.

17.
Int J Nanomedicine ; 16: 1157-1174, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33623380

RESUMO

INTRODUCTION: Candida albicans is a major opportunistic pathogen that causes a wide range of human infections. Currently available therapeutic agents are limited for treating these fungal infections due to multidrug resistance as well as their nonbiodegradability, poor biocompatibility and toxicity. In order to battle these limitations, we have synthesized a polymeric system as microcarriers to deliver the antifungal drug. The objective of the present study was to immobilize MgO/CuO nanocomposite and nystatin-loaded MgO/CuO nanocomposites in nontoxic, nonimmunogenic, biodegradable and biocompatible sodium alginate microspheres for the first time. MATERIALS AND METHODS: Nanoparticle-loaded sodium alginate microspheres were prepared by ionotropic gelation technique using calcium chloride as a cross-linker. Synthesized microspheres were characterized using standard characterization techniques and were evaluated for biological activity against MDR strain of C. albicans. RESULTS: Characterization of microspheres by Fourier-transform infrared spectroscopy confirmed loading of Nys-MgO/CuO NPs, scanning electron microscopy (SEM) revealed rough spherical beads with a highly porous surface having an average size in the range of 8-10 µm. X-ray diffraction (XRD) analyzed its semicrystalline structure. Entrapment efficiency of Nys-MgO/CuO NPs was 80% and release kinetic study revealed sustained and prolonged release of drug in pH 5.5. Flow cytometry analysis showed yeast cell death caused by Nys-MgO/CuO MS exhibits late apoptotic features. In cytotoxicity assay 5-14 mg of microspheres did not cause hemolysis. Microspheres reduced virulence traits of C. albicans such as germ tube and biofilm formation were compromised at concentration of 5 mg/mL. Antimicrobial assessment results revealed a pronounced inhibitory effect against C. albicans. CONCLUSION: The in vitro experiments have shown promising results based on good stability, Nys-MgO/CuO NP-encapsulated microspheres can be used as a prolonged controlled release system against MDR pathogenic C. albicans.


Assuntos
Alginatos/química , Candida albicans/patogenicidade , Cobre/química , Resistência a Múltiplos Medicamentos , Óxido de Magnésio/química , Microesferas , Nanocompostos/química , Nistatina/farmacologia , Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Liberação Controlada de Fármacos , Eritrócitos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Cinética , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Fenótipo , Espectroscopia de Infravermelho com Transformada de Fourier , Virulência/efeitos dos fármacos , Fatores de Virulência/metabolismo , Difração de Raios X
18.
PLoS One ; 16(8): e0255999, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34379690

RESUMO

BACKGROUND: The primary goal of the presented cross-sectional observational study was to determine the clinical and demographic risk factors for adverse coronavirus disease 2019 (COVID-19) outcomes in the Pakistani population. METHODS: We examined the individuals (n = 6331) that consulted two private diagnostic centers in Lahore, Pakistan, for COVID-19 testing between May 1, 2020, and November 30, 2020. The attending nurse collected clinical and demographic information. A confirmed case of COVID-19 was defined as having a positive result through real-time reverse transcriptase polymerase chain reaction (RT-PCR) assay of nasopharyngeal swab specimens. RESULTS: RT-PCR testing was positive in 1094 cases. Out of which, 5.2% had severe, and 20.8% had mild symptoms. We observed a strong association of COVID-19 severity with the number and type of comorbidities. The severity of the disease intensified as the number of comorbidities increased. The most vulnerable groups for the poor outcome are patients with diabetes and hypertension. Increasing age was also associated with PCR positivity and the severity of the disease. CONCLUSIONS: Most cases of COVID-19 included in this study developed mild symptoms or were asymptomatic. Risk factors for adverse outcomes included older age and the simultaneous presence of comorbidities.


Assuntos
COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/patologia , COVID-19/virologia , Comorbidade , Demografia , Complicações do Diabetes/patologia , Humanos , Hipertensão/complicações , Paquistão/epidemiologia , RNA Viral/análise , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Índice de Gravidade de Doença
19.
Infect Genet Evol ; 72: 16-24, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30822549

RESUMO

Pakistan ranks 5th among the world's highest tuberculosis (TB) burden countries and 6th among the countries with the highest prevalence of drug-resistant TB. However, insufficient data are available on the genetic structure of M. tuberculosis strains circulating in this country. The objective of this study was to explore the genetic diversity of multidrug-resistant M. tuberculosis isolates from Punjab, Pakistan with a combination of spoligotyping and 24-loci MIRU-VNTR typing. Among a total of 127 MDR isolates studies, 53 spoligotypes were obtained, split into 14 clusters (n = 88, 69.3%, 2-29 isolates per cluster) and 39 (30.7%) unique patterns. At the phylogenetic level, the most prevalent sublineage was CAS1_DELHI (n = 53, 41.7%), mostly represented by ST 1942 (n = 29, 22.8%), followed by T1 (n = 14, 11%) and Beijing (n = 10, 7.8%). The remaining nine sublineages (CAS, MANU2, EAI5, T2, LAM10_CAM, H1, X1, H4 and CAS2) involved altogether 24 (18.9%) isolates. Twenty-six (20.5%) isolates could not be assigned to any specific clade. MIRU-VNTR typing identified 123 (96.8%), 97 (76.4%) and 65 (51.2%) unique types with a tolerance of 0, 1, and 2 locus differences between the patterns. Upon combined spoligotyping and MIRU-VNTR typing analysis, 123 (96.8%), 108 (85%), and 91 (71.7%) unique types were identified if a tolerance of 0, 1, and 2 locus differences in the MIRU-VNTR patterns was assumed, respectively. Based on the clustering results, the transmission rate for MDR-TB cases under the study was calculated at 3.2%, 15%, and 28.3%. Overall, three clades, namely CAS1_DELHI, T1, and Beijing accounted for the majority of MDR-TB cases in Pakistan. Up to a third of the cases were clustered upon combined spoligotyping and MIRU-VNTR typing, suggesting a moderate level of active transmission.


Assuntos
Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Técnicas de Tipagem Bacteriana , Variação Genética , Humanos , Repetições Minissatélites , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Mycobacterium tuberculosis/isolamento & purificação , Paquistão/epidemiologia , Filogenia , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/transmissão
20.
Biomed Res Int ; 2018: 4543723, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29607320

RESUMO

The present study was proposed to investigate the toxicological and prophylactic potential of ethanolic extracts of Rosa damascena and Nymphaea alba and their mixture in albino mice. For toxicity study, three different doses of plant extracts were orally administrated to three groups of mice for 14 successive days. Blood biochemistry and histological examinations of liver and kidney revealed that these extracts had no harmful effects up to 1000 mg/kg. To determine the prophylactic effects of Rosa damascena, Nymphaea alba, and their mixture, an infection model of Listeria monocytogenes was established in a pilot study. Establishment of infection was confirmed by changes in haematological parameters and reisolation of Listeria monocytogenes from different tissues. Results showed that these extracts alone or in combination could restrict the growth of Listeria monocytogenes in different organs. Neutrophils were high in positive control group but remained in normal range in all treated groups. Listeria monocytogenes was recovered in low numbers from animals treated with extract of single plant but was negligible in group treated with mixture of extract of plants. Platelets count was increased in treated groups as compared to control. Results confirmed that these extracts are potent source of antimicrobial compounds and that they have synergistic effect in combined form.


Assuntos
Antibacterianos/farmacologia , Listeria monocytogenes/metabolismo , Listeriose/tratamento farmacológico , Nymphaea/química , Extratos Vegetais/farmacologia , Rosa/química , Administração Oral , Animais , Antibacterianos/química , Listeriose/metabolismo , Listeriose/patologia , Masculino , Camundongos , Extratos Vegetais/química
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa