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1.
J Basic Microbiol ; : e2400129, 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38922954

RESUMO

Nanobiotechnology has gained significant attention due to its capacity to generate substantial benefits through the integration of microbial biotechnology and nanotechnology. Among microbial organisms, Actinomycetes, particularly the prominent genus Streptomycetes, have garnered attention for their prolific production of antibiotics. Streptomycetes have emerged as pivotal contributors to the discovery of a substantial number of antibiotics and play a dominant role in combating infectious diseases on a global scale. Despite the noteworthy progress achieved through the development and utilization of antibiotics to combat infectious pathogens, the prevalence of infectious diseases remains a prominent cause of mortality worldwide, particularly among the elderly and children. The emergence of antibiotic resistance among pathogens has diminished the efficacy of antibiotics in recent decades. Nevertheless, Streptomycetes continue to demonstrate their potential by producing bioactive metabolites for the synthesis of nanoparticles. Streptomycetes are instrumental in producing nanoparticles with diverse bioactive characteristics, including antiviral, antibacterial, antifungal, antioxidant, and antitumor properties. Biologically synthesized nanoparticles have exhibited a meaningful reduction in the impact of antibiotic resistance, providing resources for the development of new and effective drugs. This review succinctly outlines the significant applications of Streptomycetes as a crucial element in nanoparticle synthesis, showcasing their potential for diverse and enhanced beneficial applications.

2.
Int J Biol Macromol ; 268(Pt 1): 131558, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38614166

RESUMO

Water contamination caused by toxic compounds has emerged as one of the most severe challenges worldwide. Biomass-based nanocomposites offer a sustainable and renewable alternative to conventional materials. In this study, a nanocomposite of mint and cellulose acetate (Mint-CA) was prepared and employed as a supportive material for Cu nanoparticles (CuNPs) and Ag nanoparticles (AgNPs). The selectivity of CuNPs@mint-CA and AgNPs@mint-CA was assessed by comparing their performance in the reduction reaction of various dyes solutions. AgNPs@mint-CA exhibited superior catalytic performance, with a removal of 95.2 % for methyl orange (MO) compared to 68 % with CuNPs@mint-CA. The absorption spectra of MO exhibited a distinct peak at 464 nm. The reduction reaction of MO by AgNPs@mint-CA followed pseudo-first-order-kinetic with a rate constant of k = 0.0063 min-1 (R2 = 0.928). The highest removal of MO was achieved under the following conditions: a catalyst weight of 40 mg, an initial MO concentration of 0.07 mM, the addition of 0.5 mL of 0.1 M NaBH4, and a temperature of 25 °C. Furthermore, the AgNPs@mint-CA catalyst exhibited exceptional reducibility even after five use cycles, highlighting its potential for efficiently removing MO.


Assuntos
Compostos Azo , Celulose , Nanopartículas Metálicas , Compostos Azo/química , Celulose/química , Celulose/análogos & derivados , Nanopartículas Metálicas/química , Catálise , Prata/química , Nanocompostos/química , Mentha/química , Oxirredução , Poluentes Químicos da Água/química , Cinética , Cobre/química
3.
Chemosphere ; 355: 141743, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38513958

RESUMO

Silver oxide doped iron oxide (Ag2O-Fe2O3) nanocatalyst was prepared and coated on cotton cloth (CC) as well as wrapped in sodium alginate (Alg) hydrogel. Ag2O-Fe2O3 coated CC (Ag2O-Fe2O3/CC) and Ag2O-Fe2O3 wrapped Alg (Ag2O-Fe2O3/Alg) were utilized as catalysts in reduction reaction of 4-nitrophenol (4-NP), congo red (CR), methylene blue (MB) and potassium ferricyanide (K3[Fe(CN)6]). Ag2O-Fe2O3/CC and Ag2O-Fe2O3/Alg were found to be effective and selective catalyst for the reaction of K3[Fe(CN)6]. Further amount of catalyst, K3[Fe(CN)6] quantity, amount of NaBH4, stability of catalyst and recyclability were optimized for the reaction of K3[Fe(CN)6] reduction. Ag2O-Fe2O3/Alg and Ag2O-Fe2O3/CC were appeared to be the stable catalysts by maintaining high activity during recyclability tests showing highest reaction rate constants (kapp) of 0.3472 and 0.5629 min-1, correspondingly. However, Ag2O-Fe2O3/CC can be easily recovered as compared to Ag2O-Fe2O3/Alg by simply removing from the reaction which is the main advantage of Ag2O-Fe2O3/CC. Moreover, Ag2O-Fe2O3/Alg and Ag2O-Fe2O3/CC were also examined in real samples and found useful for K3[Fe(CN)6] reduction involving real samples. The Ag2O-Fe2O3/CC nanocatalyst is a cost and time saving material for economical reduction of K3[Fe(CN)6] and environmental safety.


Assuntos
Alginatos , Compostos Férricos , Ferricianetos , Nanocompostos , Óxidos , Compostos de Prata
4.
World J Microbiol Biotechnol ; 40(3): 103, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38372854

RESUMO

Certain factors hinder the commercialization of biodesulfurization process, including low substrate-specificity of the currently reported desulfurizing bacteria and restricted mass transfer of organic-sulfur compounds in biphasic systems. These obstacles must be addressed to clean organic-sulfur rich petro-fuels that pose serious environmental and health challenges. In current study, a dibenzothiophene desulfurizing strain, Gordonia rubripertincta W3S5 (source: oil contaminated soil) was systematically evaluated for its potential to remove sulfur from individual compounds and mixture of organic-sulfur compounds. Metabolic and genetic analyses confirmed that strain W3S5 desulfurized dibenzothiophene to 2-hydroxybiphenyl, suggesting that it follows the sulfur specific 4 S pathway. Furthermore, this strain demonstrated the ability to produce trehalose biosurfactants (with an EI24 of 53%) in the presence of dibenzothiophene, as confirmed by TLC and FTIR analyses. Various genome annotation tools, such as ClassicRAST, BlastKOALA, BV-BRC, and NCBI-PGAP, predicted the presence of otsA, otsB, treY, treZ, treP, and Trehalose-monomycolate lipid synthesis genes in the genomic pool of strain W3S5, confirming the existence of the OtsAB, TreYZ, and TreP pathways. Overall, these results underscore the potential of strain W3S5 as a valuable candidate for enhancing desulfurization efficiency and addressing the mass transfer challenges essential for achieving a scaled-up scenario.


Assuntos
Petróleo , Trealose , Solo , Tiofenos , Enxofre
5.
Curr Pharm Biotechnol ; 23(3): 318-336, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33882804

RESUMO

BACKGROUND: Ajuga bracteosa is a traditional herb used against various diseases. OBJECTIVES: Current research aimed to investigate the anti-diabetic and hepato-protective effect of green synthesized silver nanoparticles (ABAgNPs) using Ajuga bracteosa aqueous extract (ABaqu). METHODS: In vitro anti-diabetic and cytotoxic effects were carried out via α- glucosidase inhibition, brine shrimp lethality, and protein kinase inhibition assays. For in vivo screening of 200 mg/kg and 400 mg/kg of both ABAgNPs and ABaqu in alloxan-induced and CCl4-induced Swiss albino mice were used. Liver and kidney functional markers, hematology, and histopathological studies were carried out after 14 days of administration. RESULTS: In vivo antidiabetic and anti-cancerous effects showed valuable anti-hyperglycemic and hepatoprotective potential when mice were treated with ABaqu and ABAgNPs. A significant reduction in the blood glucose level was recorded when ABaqu and ABAgNPs were administrated orally compared to Glibenclamide treated group. Significant reduction in ALT, AST, ALP, urea, uric acid, and creatinine was recorded in ABaqu and ABAgNPs treated diabetic mice. The hepato-protective findings indicated that ALT, ALP, AST were elevated in CCl4-induced mice while declined in both ABAgNPs and ABaqu treated CCl4-induced mice. Histopathological examination revealed that ABAgNPs have hepato-protective activity. CONCLUSION: It was concluded that ABAgNPs and ABaqu possessed strong anti-diabetic and hepatoprotective phytoconstituents, which could be used in the prevention of diseases.


Assuntos
Ajuga , Diabetes Mellitus Experimental , Nanopartículas Metálicas , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Fígado , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/farmacologia , Prata
6.
Curr Pharm Des ; 25(34): 3645-3663, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31656147

RESUMO

Water pollution due to waste effluents of the textile industry is seriously causing various health problems in humans. Water pollution with pathogenic bacteria, especially Escherichia coli (E. coli) and other microbes is due to the mixing of fecal material with drinking water, industrial and domestic sewage, pasture and agricultural runoff. Among the chemical pollutants, organic dyes due to toxic nature, are one of the major contaminants of industrial wastewater. Adequate sanitation services and drinking quality water would eliminate 200 million cases of diarrhea, which results in 2.1 million less deaths caused by diarrheal disease due to E. coli each year. Nanotechnology is an excellent platform as compared to conventional treatment methods of water treatment and remediation from microorganisms and organic dyes. In the current study, toxicity and carcinogenicity of the organic dyes have been studied as well as the remediation/inactivation of dyes and microorganism has been discussed. Remediation by biological, physical and chemical methods has been reviewed critically. A physical process like adsorption is cost-effective, but can't degrade dyes. Biological methods were considered to be ecofriendly and cost-effective. Microbiological degradation of dyes is cost-effective, eco-friendly and alternative to the chemical reduction. Besides, certain enzymes especially horseradish peroxidase are used as versatile catalysts in a number of industrial processes. Moreover, this document has been prepared by gathering recent research works related to the dyes and microbial pollution elimination from water sources by using heterogeneous photocatalysts, metal nanoparticles catalysts, metal oxides and enzymes.


Assuntos
Biodegradação Ambiental , Corantes/toxicidade , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/toxicidade , Carcinógenos/toxicidade , Escherichia coli , Humanos , Nanotecnologia , Indústria Têxtil
7.
Recent Pat Nanotechnol ; 10(3): 181-188, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27136929

RESUMO

BACKGROUND: Potable, clean and safe water is the basic need for all human beings. Major portion of the earth is occupied by water, however, this is contaminated by rapid industrialization, improper sewage and natural calamities and man-made activates, which produce several water-borne and fetal diseases. In this review we presented some recent patent for environmental remediation. METHODS: Various technologies have been developed for the treatment of waste water consist of chemical, membrane, filtration, sedimentation, chlorination, disinfection, electrodialysis, electrolysis, reverse osmosis and adsorption. Among these entire phenomenon's, adsorption was the most efficient method for wastewater treatment, because it is a quick and cheap technology which signifies extensive practical applications. Adsorption phenomenon has been tactfully used for the removal of biological waste as well as soluble and insoluble material with a removal efficacy of 90-99%. RESULTS: Clean water supply is limited to human beings. The people in the developing countries have less or no access to the clean and potable water. The shortage of potable water resources and long term safe water deficiencies are some of the leading problems worldwide. In this review, we have explained in the detail adsorption phenomena of chitosan, pharmaceutical importance and other applications. It is worth to say that adsorption technologies using chitosan and its derivative is one of the quickest and cost effective methods for the wastewater treatment. The review comprises of ninety eight references. This review also covers various patents vis-a-vis the role of chitosan-nanocomposite in environmental application for wastewater treatment. CONCLUSION: Chitosan is a pseudo-neutral cationic polymer which is formed by the de-acetylation of chitin polymer. Various patent on chitosan and chitosan-nanocomposite were taken into account related to wastewater purification. We have found that chitosan and chitosan-nanocomposite are used for the removal of viruses, bacteria, cryptosporidium oocysts and giardia cysts, soluble and insoluble organic pollutants, poly aromatic hydrocarbons and heavy metals from wastewater. In this study, we also found that chitosan and chitosan-nanocomposite are selected for the removal of transition metals.


Assuntos
Quitosana/química , Recuperação e Remediação Ambiental , Nanocompostos/química , Purificação da Água , Metais Pesados , Patentes como Assunto , Águas Residuárias , Poluição da Água
8.
Biosens Bioelectron ; 44: 21-6, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23384765

RESUMO

Electrochemical DNA biosensor was used to study the interaction of methotrexate (MTX) with DNA immobilized on the bare surface of glassy carbon electrode (GCE). The binding mechanism of MTX with DNA was elucidated by using constant current potentiometric technique further supported by UV-Visible and FT-IR studies. The decrease in guanine peak area was used as an analytical signal for the interaction of drug with DNA in acetate buffer solution at pH 4.2 (20% ethanol). The binding constant (K) value calculated for MTX was 3.821×10(5)M(-1). UV-Visible studies indicated hyperchromic and hypsochromic shifts in the maximum absorption bands of MTX after interaction with DNA. FT-IR investigations of MTX-DNA interaction revealed significant changes in the characteristic IR absorption bands of all the bases and phosphate groups of DNA. Furthermore, the shift of characteristics bands of C=O, N-H, C-H and O-H groups of MTX endow evidence for the interaction of MTX with DNA supporting the intercalative binding between them.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , DNA/metabolismo , Metotrexato/farmacologia , Animais , DNA/química , Substâncias Intercalantes/farmacologia , Potenciometria , Salmão , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
9.
J Coll Physicians Surg Pak ; 22(5): 311-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22538037

RESUMO

OBJECTIVE: To compare the quality of life and symptomatic improvement after palliative radiotherapy to brain metastasis using two different treatment protocols. STUDY DESIGN: Comparative study. PLACE AND DURATION OF STUDY: Bahawalpur Institute of Nuclear Medicine and Oncology, Bahawalpur, from January 2009 to November 2010. METHODOLOGY: Patients presenting with brain metastasis referred to Bahawalpur Institute of Nuclear Medicine and Oncology, Bahawalpur for whole brain radiotherapy (WBRT) were included. Patients were divided in two groups. In group A WBRT 30 Gys in 10 fractions were given. While in group B 30 Gys in 15 fractions to whole brain followed by 20 Gys in 10 fractions boost to primary metastatic site with 2 cm margins were given. Follow-up was done at 1 and 3 months. RESULTS: A total of 46 patients with brain metastasis were enrolled with median Karnofsky performance score 50. Median age was 64 years. Most common presenting symptoms were headache, weakness, balance problem and early fatigability. Fifty percent of patients had improvement in their presenting symptoms after completion of palliative radiotherapy at one month and three months follow-up. There was a statistically significant improvement in headache, nausea or vomiting, focal weakness, dizziness, balance problem and problems with smell, hearing and tingling sensation in group B patients as compared to group A. CONCLUSION: More controlled and better quality of life was observed in patient given 30 Gys in 15 fractions followed by a boost of 20 fractions to primary metastatic site versus WBRT with 30 Gys in 10 fractions and in patients with metastatic sites are less than three and having difference not more than 2 cm apart between two metastatic sites.


Assuntos
Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Irradiação Craniana/métodos , Cuidados Paliativos/métodos , Qualidade de Vida , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Fracionamento da Dose de Radiação , Relação Dose-Resposta à Radiação , Feminino , Seguimentos , Humanos , Avaliação de Estado de Karnofsky , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Paquistão , Radioterapia (Especialidade) , Dosagem Radioterapêutica , Medição de Risco , Análise de Sobrevida , Doente Terminal , Fatores de Tempo , Resultado do Tratamento
10.
J Coll Physicians Surg Pak ; 19(1): 62-3, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19149986

RESUMO

A Multiple Myeloma (MM) is rare in younger age group. We report MM in a 30-year-old female, who presented with multiple lytic areas upon skeletal survey, but with negative Bence Jones protein. Bone marrow biopsy confirmed it to be a case of multiple myeloma. Patient was put on chemotherapy and radiography to which she responded and now is ambulatory.


Assuntos
Proteína de Bence Jones/análise , Mieloma Múltiplo/patologia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Exame de Medula Óssea , Diagnóstico Diferencial , Feminino , Humanos , Mieloma Múltiplo/terapia , Metástase Neoplásica , Radioterapia Adjuvante
11.
Braz. j. microbiol ; 39(1): 143-150, Jan.-Mar. 2008. tab
Artigo em Inglês | LILACS | ID: lil-480690

RESUMO

Culturable bacterial biodiversity and industrial importance of the isolates indigenous to Khewra salt mine, Pakistan was assessed. PCR Amplification of 16S rDNA of isolates was carried out by using universal primers FD1 and rP1and products were sequenced commercially. These gene sequences were compared with other gene sequences in the GenBank databases to find the closely related sequences. The alignment of these sequences with sequences available from GenBank database was carried out to construct a phylogenetic tree for these bacteria. These genes were deposited to GenBank and accession numbers were obtained. Most of the isolates belonged to different species of genus Bacillus, sharing 92-99 percent 16S rDNA identity with the respective type strain. Other isolates had close similarities with Escherichia coli, Staphylococcus arlettae and Staphylococcus gallinarum with 97 percent, 98 percent and 99 percent 16S rDNA similarity respectively. The abilities of isolates to produce industrial enzymes (amylase, carboxymethylcellulase, xylanase, cellulase and protease) were checked. All isolates were tested against starch, carboxymethylcellulose (CMC), xylane, cellulose, and casein degradation in plate assays. BPT-5, 11,18,19 and 25 indicated the production of copious amounts of carbohydrates and protein degrading enzymes. Based on this study it can be concluded that Khewra salt mine is populated with diverse bacterial groups, which are potential source of industrial enzymes for commercial applications.


Avaliou-se a biodiversidade e a importância industrial de bactérias indígenas da mina de sal Khewra, Paquistão. Efetuou-se a amplificação do 16S rDNA dos isolados por PCR empregando-se os iniciadores universais FD1 e rP1, e os produtos foram seqüenciados comercialmente. Essas seqüências de genes foram comparadas com outras seqüências disponíveis no GenBank a fim de encontrar seqüências relacionadas, construindo-se uma árvore filogenética para essas bactérias. Os genes foram depositados no GenBank obtendo-se os números de acesso. A maioria dos isolados pertenceu a diferentes espécies do gênero Bacillus, apresentando 92-99 por cento de identidade de 16S rDNA com a respectiva cepa de referencia. Outros isolados apresentaram alta similaridade com Escherichia coli, Staphylococcus arlettae e Staphylococcus gallinarum, com 97 por cento, 98 por cento e 99 por cento de similaridade de16S rDNA, respectivamente. A capacidade dos isolados produzirem enzimas industriais (amilase, carboximetilcelulase, xilanase, celulase e protease) foi verificada. Todos os isolados foram testados em placas quanto a degradação de amido, carboximetilcelulose, xilana, celulose e caseína. Os isolados BPT-5, 11, 18, 19 e 25 produziram grandes quantidades de enzimas degradadoras de carboidratos e proteínas. Conclui-se que a mina de Sal Khewra apresenta diferentes grupos de bactérias, que são fontes potenciais de enzimas industriais de aplicação comercial.


Assuntos
Sequência de Bases , Bactérias Anaeróbias Gram-Negativas/enzimologia , Bactérias Anaeróbias Gram-Negativas/isolamento & purificação , Bactérias Anaeróbias/enzimologia , Bactérias Anaeróbias/isolamento & purificação , Enzimas/análise , Técnicas In Vitro , Salinidade , Biodiversidade , Meio Ambiente , Métodos , Mineração
12.
Biosens Bioelectron ; 22(11): 2471-7, 2007 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-17085032

RESUMO

The interaction of sildenafil citrate (Viagra) with DNA was studied by using an electrochemical DNA biosensor. The binding mechanism of sildenafil citrate was elucidated by using constant current potentiometry and differential pulse voltammetry at DNA-modified glassy carbon electrode. The decrease in the guanine oxidation peak area or peak current was used as an indicator for the interaction in 0.2M acetate buffer (pH 5). The binding constant (K) values obtained were 2.01+/-0.05 x 10(5) and 1.97+/-0.01 x 10(5)M(-1) with constant current potentiometry and differential pulse voltammetry, respectively. A linear dependence of the guanine peak area or peak current was observed within the range of 1-40 microM sildenafil citrate with slope=-2.74 x 10(-4)s/microM, r=0.989 and slope=-2.78 x 10(-3)microA/microM, r=0.995 by using constant current potentiometry and differential pulse voltammetry, respectively. Additionally, binding constant values for sildenafil citrate-DNA interaction were determined for the pH range of 4-8 and in biological fluids (serum and urine) at pH 5. The influence of sodium and calcium ions was also studied to elucidate the mechanism of sildenafil citrate-DNA interaction under different solution conditions. The present study may prove to be helpful in extending our understanding of the anticancer activity of sildenafil citrate from cellular to DNA level.


Assuntos
Técnicas Biossensoriais/métodos , DNA/análise , DNA/química , Eletroquímica/métodos , Piperazinas/análise , Piperazinas/química , Sulfonas/análise , Sulfonas/química , Técnicas Biossensoriais/instrumentação , Misturas Complexas/análise , Misturas Complexas/química , Eletroquímica/instrumentação , Concentração de Íons de Hidrogênio , Purinas/análise , Purinas/química , Citrato de Sildenafila , Soluções
13.
J Coll Physicians Surg Pak ; 16(12): 760-3, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17125634

RESUMO

OBJECTIVE: To assess the role of hysterosalpingoscintigraphy (HSSG) in the evaluation of fallopian tube patency and function and compare the results with hysterosalpingography (HSG) and laparoscopy (LS). DESIGN: Cross-sectional study. PLACE AND DURATION OF STUDY: The study was conducted at Multan Institute of Nuclear Medicine and Radiotherapy (MINAR), Multan from August 2004 to February 2005. PATIENTS AND METHODS: HSSG was performed after instillation of 4mCi (148 MBq) 99mTechnetium-macroaggregated albumin (99mTc-MAA) in posterior vaginal fornix in 65 patients. Serial static images were acquired in supine position at 1 hour, 2 hours, 3 hours and, if needed, at 24 hours. The results were compared to the findings on LS and HSG. RESULTS: Out of 65 patients, 37 (56.9%) patients had bilateral blocked tubes, 17 (26.1%) patients had bilateral patent tubes, 6 (9.2%) patients had blocked left tube and 5 (7.1%) patients had blocked right tube. The calculated sensitivity, specificity, positive predicted value (PPV), negative predicted value (NPV) and accuracy for HSSG were 90%, 83%, 90% and 90% respectively. The agreement between HSSG and LS was found in 32 out of 35 patients and agreement between HSG and HSSG was found in 24 out of 30 patients. CONCLUSION: This simple procedure can delineate tubal physiology; in selected cases it can replace HSG and in others augment the information gathered by HSG. HSSG should be part of the infertility workup algorithm.


Assuntos
Tubas Uterinas/diagnóstico por imagem , Infertilidade Feminina/diagnóstico por imagem , Testes de Obstrução das Tubas Uterinas , Feminino , Humanos , Histerossalpingografia , Infertilidade Feminina/diagnóstico , Laparoscopia , Cintilografia , Compostos Radiofarmacêuticos , Agregado de Albumina Marcado com Tecnécio Tc 99m
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