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1.
Microb Pathog ; 174: 105923, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36526035

RESUMO

Antibiotic resistance has become an indispensably alarming menace to the global community. The primary factors are overuse and abuse of antibiotics, lack of novel medicines under development, the health care industry's focus on profit, and the absence of diagnostic testing prior to the prescription of antibiotics. Additionally, over the past few decades, the main factors contributing to the global spread of antibiotic resistance have been the overuse of antibiotics in livestock and other animals, drug efficacy, development of fewer new vaccines, environmental toxicity, transmission through travel, and lack of funding for healthcare research and development. These factors have accelerated resistance in microorganisms through structural and functional modifications in bacteria such as reduced drug permeability, increased efflux pumps, enzymatic antibiotic modification, and change in drug target, intracellular infection, and biofilm creation. There has been an increase in resistance during the pandemic and among cancer patients due to improper prescriptions. A number of modern therapeutic alternatives have been developed to curb widespread antibiotic resistance such as nanoparticle, bacteriophage, and antimicrobial biochemical approaches. It is high time to explore new alternatives to curtail enormous increase in resistant pathogens which could be an incurable global confrontation. This review highlights the complete insight on the global drivers of resistance along with the modes of action and impacts, finally discussing the latest therapeutic alternatives.


Assuntos
Bactérias , Pandemias , Animais , Resistência Microbiana a Medicamentos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Viagem
2.
Microb Pathog ; 179: 106088, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37004965

RESUMO

Significant efforts and initiatives were already made in the health care systems, however in the last few years; our world is facing emergences of viral infections which potentially leading to considerable challenges in terms of higher morbidity, mortality, increased and considerable financial loads on the affected populations. Over ten major epidemics or pandemics have been recorded in the twenty-first century, the ongoing coronavirus pandemic being one of them. Viruses being distinct obligate pathogens largely dependent on living beings are considered as one of the prominent causes of death globally. Although effective vaccines and antivirals have led to the eradication of imperative viral pathogens, the emergences of new viral infections as well as novel drug-resistant strains have necessitated the implementation of ingenious and efficient therapeutic approaches to treat viral outbreaks in the future. Nature being a constant source of tremendous therapeutical resources has inspired us to develop multi-target antiviral drugs, overcoming the challenges and limitations faced by pharmaceutical industry. Recent breakthroughs in the understanding of the cellular and molecular mechanisms of viral reproduction have laid the groundwork for potential treatment approaches including antiviral gene therapy relying on the application of precisely engineered nucleic acids for disabling pathogen replication. The development of RNA interference and advancements in genome manipulating tools have proven to be especially significant in this regard. In this review, we discussed mode of actions and pathophysiological events associated with the viral infections; followed by distributions, and advancement made towards the detection strategies for timely diagnosis. In the later section, current approaches to cope up the viral pathogens and their key limitations have also been elaborated. Lastly, we also explored some novel and potential targets to treat such infections, where attentions were made on next generation gene editing technologies.


Assuntos
COVID-19 , Viroses , Vírus , Humanos , Viroses/diagnóstico , Viroses/tratamento farmacológico , Antivirais/uso terapêutico , Vírus/genética , Edição de Genes
3.
Anal Biochem ; 671: 115150, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37054862

RESUMO

DNA polymerases are the enzymes able to replicate the genetic information in nucleic acid. As a result, they are necessary to copy the complete genome of every living creature before cell division and sustain the integrity of the genetic information throughout the life of each cell. Any organism that uses DNA as its genetic information, whether unicellular or multicellular, requires one or more thermostable DNA polymerases to thrive. Thermostable DNA polymerase is important in modern biotechnology and molecular biology because it results in methods such as DNA cloning, DNA sequencing, whole genome amplification, molecular diagnostics, polymerase chain reaction, synthetic biology, and single nucleotide polymorphism detection. There are at least 14 DNA-dependent DNA polymerases in the human genome, which is remarkable. These include the widely accepted, high-fidelity enzymes responsible for replicating the vast majority of genomic DNA and eight or more specialized DNA polymerases discovered in the last decade. The newly discovered polymerases' functions are still being elucidated. Still, one of its crucial tasks is to permit synthesis to resume despite the DNA damage that stops the progression of replication-fork. One of the primary areas of interest in the research field has been the quest for novel DNA polymerase since the unique features of each thermostable DNA polymerase may lead to the prospective creation of novel reagents. Furthermore, protein engineering strategies for generating mutant or artificial DNA polymerases have successfully generated potent DNA polymerases for various applications. In molecular biology, thermostable DNA polymerases are extremely useful for PCR-related methods. This article examines the role and importance of DNA polymerase in a variety of techniques.


Assuntos
Biotecnologia , DNA Polimerase Dirigida por DNA , Humanos , Estudos Prospectivos , DNA Polimerase Dirigida por DNA/metabolismo , Biotecnologia/métodos , Engenharia de Proteínas , Reação em Cadeia da Polimerase , Replicação do DNA
4.
Bioorg Chem ; 127: 105942, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35709577

RESUMO

Nature is a dexterous and prolific chemist for cataloging a number of hostile niches that are the ideal residence of various thermophiles. Apart from having other species, these subsurface environments are considered a throne of bacterial genus Thermotoga. The genome sequence of Thermotogales encodes complex and incongruent clusters of glycoside hydrolases (GHs), which are superior to their mesophilic counterparts and play a prominent role in various applications due to their extreme intrinsic stability. They have a tremendous capacity to use a wide variety of simple and multifaceted carbohydrates through GHs, formulate fermentative hydrogen and bioethanol at extraordinary yield, and catalyze high-temperature reactions for various biotechnological applications. Nevertheless, no stringent rules exist for the thermo-stabilization of biocatalysts present in the genus Thermotoga. These enzymes endure immense attraction in fundamental aspects of how these polypeptides attain and stabilize their distinctive three-dimensional (3D) structures to accomplish their physiological roles. Moreover, numerous genome sequences from Thermotoga species have revealed a significant fraction of genes most closely related to those of archaeal species, thus firming a staunch belief of lateral gene transfer mechanism. However, the question of its magnitude is still in its infancy. In addition to GHs, this genus is a paragon of encapsulins which carry pharmacological and industrial significance in the field of life sciences. This review highlights an intricate balance between the genomic organizations, factors inducing the thermostability, and pharmacological and industrial applications of GHs isolated from genus Thermotoga.


Assuntos
Bactérias , Glicosídeo Hidrolases , Bactérias/genética , Glicosídeo Hidrolases/genética , Thermotoga
5.
Curr Heart Fail Rep ; 19(6): 435-444, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36205832

RESUMO

PURPOSE OF REVIEW: To evaluate remote monitoring using implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy defibrillator (CRT-D) devices as an adjunctive tool to the traditional care of patients with heart failure (HF). RECENT FINDINGS: We included 11 trials encompassing 5965 patients. Absolute risk difference (ARD) with 95% credible interval (CrI) was estimated. Pooled (posterior) risk difference was computed using Bayesian hierarchical methods. The ARD for mortality was centered at - 0.01 (95% CrI: - 0.03; 0.01, Tau: 0.02), with an 82% probability of ARD of ICD/CRT-D remote monitoring with respect to control being less than 0. The ARD for cardiovascular mortality was centered at - 0.03 (95% CrI: - 0.11; 0.05, Tau: 0.10), with an 84% probability of ARD of ICD/CRT-D remote monitoring with respect to control being less than 0. ICD/CRT-D remote monitoring in patients with HF is associated with a higher probability of reduced all-cause and cardiovascular mortality compared with standard care alone.


Assuntos
Terapia de Ressincronização Cardíaca , Desfibriladores Implantáveis , Insuficiência Cardíaca , Humanos , Terapia de Ressincronização Cardíaca/efeitos adversos , Teorema de Bayes , Volume Sistólico , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
6.
Drug Metab Rev ; 52(3): 408-424, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32546018

RESUMO

Despite to outbreaks of highly pathogenic beta and alpha coronaviruses including severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and human coronavirus, the newly emerged 2019 coronavirus (COVID-19) is considered as a lethal zoonotic virus due to its deadly respiratory syndrome and high mortality rate among the human. Globally, more than 3,517,345 cases have been confirmed with 243,401 deaths due to Acute Respiratory Distress Syndrome (ARDS) caused by COVID-19. The antiviral drug discovery activity is required to control the persistence of COVID-19 circulation and the potential of the future emergence of coronavirus. However, the present review aims to highlight the important antiviral approaches, including interferons, ribavirin, mycophenolic acids, ritonavir, lopinavir, inhibitors, and monoclonal antibodies (mAbs) to provoke the nonstructural proteins and deactivate the structural and essential host elements of the virus to control and treat the infection of COVID-19 by inhibiting the viral entry, viral RNA replication and suppressing the viral protein expression. Moreover, the present review investigates the epidemiology, diagnosis, structure, and replication of COVID-19 for better understanding. It is recommended that these proteases, inhibitors, and antibodies could be a good therapeutic option in drug discovery to control the newly emerged coronavirus.HighlightsCOVID-19 has more than 79.5% identical sequence to SARS-CoV and a 96% identical sequence of the whole genome of bat coronaviruses.Acute respiratory distress syndrome (ARDS), renal failure, and septic shock are the possible clinical symptoms associated with COVID-19.Different antivirals, including interferons, ribavirin, lopinavir, and monoclonal antibodies (mAbs) could be the potent therapeutic agents against COVID-19.The initial clinical trials on hydroquinone in combination with azithromycin showed an admirable result in the reduction of COVID-19.The overexpression of inflammation response, cytokine dysregulation, and induction of apoptosis could be an well-organized factors to reduce the pathogenicity of COVID-19.


Assuntos
Antivirais/uso terapêutico , Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Descoberta de Drogas , Pneumonia Viral/tratamento farmacológico , Anticorpos Monoclonais/uso terapêutico , Betacoronavirus/química , Betacoronavirus/genética , Betacoronavirus/fisiologia , COVID-19 , Infecções por Coronavirus/complicações , Infecções por Coronavirus/epidemiologia , Humanos , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/epidemiologia , SARS-CoV-2 , Serina Endopeptidases/fisiologia , Inibidores de Serina Proteinase/uso terapêutico , Replicação Viral , Tratamento Farmacológico da COVID-19
7.
Anal Biochem ; 599: 113741, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32339490

RESUMO

A putative cellulolytic gene (825 bp) from Thermotoga naphthophila RKU-10T was overexpressed as an active soluble endo-1,4-ß-glucanase (TnCel12B), belongs to glycoside hydrolase family 12 (GH12), in a mesophilic expression host. Heterologous expression and engineered bacterial cell mass was improved through specific strategies (induction and cultivation). Hence, intracellular activity of TnCel12B was enhanced in ZYBM9 modified medium (pH 7.0) by 8.38 and 6.25 fold with lactose (200 mM) and IPTG (0.5 mM) induction, respectively; and 6.95 fold was increased in ZYP-5052 auto-inducing medium after 8 h incubation at 26 °C (200 rev min-1). Purified TnCel12B with a molecular weight of ~32 kDa, was optimally active at 90 °C and pH 6.0; and exhibited prodigious stability over a wide range of temperature (50-85 °C) and pH (5.0-9.0) for 8 h TnCel12B displayed great resistance towards different chemical modulators, though activity was improved by Mg2+, Zn2+, Pb2+ and Ca2+. Purified TnCel12B had affinity with various substrates but peak activity was observed toward barley ß-glucan (1664 U mg-1) and carboxymethyl cellulose (736 U mg-1). The values of Km, Vmax, kcat, and kcatKm-1 were found to be 4.63 mg mL-1, 916 µmol mg-1min-1, 1326.7 s-1 and 286.54 mL mg-1 s-1, respectively using CMC substrate. All noteworthy features of TnCel12B make it an appropriate industrial candidate for bioethanol production and various other potential applications.


Assuntos
Proteínas de Bactérias , Celulase , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Celulase/química , Celulase/isolamento & purificação , Clonagem Molecular , Microbiologia Industrial , Thermotoga/enzimologia , Thermotoga/genética
8.
Mol Biol Rep ; 45(5): 1479-1490, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30073589

RESUMO

There has been an ascending growth in the capacity of information being generated. The increased production of data in turn has put forward other challenges as well thus, and there is the need to store this information and not only to store it but also to retain it for a prolonged time period. The reliance on DNA as a dense storage medium with high storage capacity and its ability to withstand extreme environmental conditions has increased over the past few years. There have been developments in reading and writing different forms of data on DNA, codes for encrypting data and using DNA as a way of secret writing leading towards new styles like stenography and cryptography. The article outlines different methods adopted for storing digital data on DNA with pros and cons of each method that has been applied plus the advantages and limitations of using DNA as a storage medium.


Assuntos
Computadores Moleculares/tendências , DNA/genética , Bases de Dados Genéticas/tendências , Armazenamento e Recuperação da Informação/métodos , Armazenamento e Recuperação da Informação/tendências , Algoritmos , Sequência de Bases
9.
Vasc Med ; 22(4): 316-323, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28436300

RESUMO

Our objective was to determine the relative merits of intervention or observation of type II endoleaks (T2Ls). A retrospective analysis was performed on 386 infra-renal endovascular aneurysm repair (IR-EVAR) patients from 2006 to 2015. Annual surveillance imaging of patients undergoing EVAR at our centre were analysed, and all endoleaks were subjected to a multidisciplinary team meeting for consideration and treatment. In the 10-year time frame, 386 patients (79.5±8.7 years) underwent an IR-EVAR. Eighty-one patients (21.0%) developed a T2L and intervention was undertaken in 28 (34.6%): 17 (60.7%) were treated via a transarterial approach (TA) and 11 (39.3%) using the translumbar approach (TL). Fifty-three patients (65.4%) with T2Ls were managed conservatively. Patients who received T2L treatment had a greater proportion of recurrent T2Ls than patients who were conservatively managed ( p=0.032). T2Ls associated with aneurysmal growth were more resistant to treatment than those where there was no change or a decrease in aneurysm size during follow-up (0.033). There was no significant difference in the TA and TL approach with respect to endoleak repair success ( p=0.525). Treatment of a T2L did not confer a survival advantage compared to conservative management ( p=0.449) nor did the choice of either the TA or TL approach ( p=0.148). Our study suggests the development of a T2L associated with aneurysm growth may represent an aggressive phenotype that is resistant to treatment. However, this did not lead to an increased risk of mortality over follow-up. Neither a transarterial nor a translumbar approach to treating a T2L conferred superiority.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/efeitos adversos , Embolização Terapêutica , Endoleak/terapia , Procedimentos Endovasculares , Conduta Expectante , Idoso , Idoso de 80 Anos ou mais , Embolização Terapêutica/efeitos adversos , Endoleak/diagnóstico por imagem , Endoleak/etiologia , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Estimativa de Kaplan-Meier , Londres , Masculino , Fenótipo , Valor Preditivo dos Testes , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
10.
J Basic Microbiol ; 56(9): 949-62, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27112133

RESUMO

A 1.3 kb xyl-A gene encoding xylose isomerase from a hyperthermophilic eubacterium Thermotoga naphthophila RKU-10 (TnapXI) was cloned and over-expressed in Escherichia coli to produce the enzyme in mesophilic conditions that work at high temperature. The enzyme was concentrated by lyophilization and purified by heat treatment, fractional precipitation, and UNOsphere Q anion-exchange column chromatography to homogeneity level. The apparent molecular mass was estimated by SDS-PAGE to be 49.5 kDa. The active enzyme showed a clear zone on Native-PAGE when stained with 2, 3, 5-triphenyltetrazolium chloride. The optimum temperature and pH for D-glucose to D-fructose isomerization were 98 °C and 7.0, respectively. Xylose isomerase retains 85% of its activity at 50 °C (t1/2 1732 min) for 4 h and 32.5% at 90 °C (t1/2 58 min) for 2 h. It retains 90-95% of its activity at pH 6.5-7.5 for 30 min. The enzyme was highly activated (350%) with the addition of 0.5 mM Co(2+) and to a lesser extent about 180 and 80% with the addition of 5 and 10 mM Mn(2+) and Mg(2+) , respectively but it was inhibited (54-90%) in the presence of 0.5-10 mM Ca(2+) with respect to apo-enzyme. D-glucose isomerization product was also analyzed by Thin Layer Chromatography (Rf 0.65). The enzyme was very stable at neutral pH and sufficiently high temperature and required only a trace amount of Co(2+) for its optimal activity and stability. Overall, 52.2% conversion of D-glucose to D-fructose was achieved by TnapXI. Thus, it has a great potential for industrial applications.


Assuntos
Aldose-Cetose Isomerases/genética , Clonagem Molecular , Thermotoga neapolitana/enzimologia , Thermotoga neapolitana/metabolismo , Xilose/metabolismo , Sequência de Aminoácidos , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática , Escherichia coli/genética , Escherichia coli/metabolismo , Frutose/metabolismo , Glucose/metabolismo , Temperatura Alta , Modelos Moleculares , Simulação de Acoplamento Molecular , Análise de Sequência de DNA , Homologia de Sequência , Thermotoga neapolitana/genética
11.
BMC Complement Altern Med ; 15: 34, 2015 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-25888212

RESUMO

BACKGROUND: Zingiber officinale (ZO, family Zingiberaceae) has been reported for its antiemetic activity against cancer chemotherapy induced emesis in animal models and in clinics. Current study was designed to investigate ZO for potential usefulness against cisplatin induced vomiting in pigeon and its effects on central and peripheral neurotransmitters involved in the act of vomiting. METHODS: Zingiber officinale acetone fraction (ZO-ActFr) was investigated for attenuation of emesis induced by cisplatin in healthy pigeons. Neurotransmitters DA, 5HT and their metabolites DOPAC, HVA and 5HIAA were analyzed using High Performance Liquid Chromatography system coupled with electrochemical detector in area postrema, brain stem and intestine. Antiemetic effect of ZO-ActFr was correlated with central and intestinal neurotransmitters levels in pigeon. RESULTS: Cisplatin (7 mg/kg i.v.) induced emesis without lethality upto the observation period. ZO-ActFr (25, 50 & 100 mg/kg) attenuated cisplatin induced emesis ~ 44.18%, 58.13% (P < 0.05) and 27.9%, respectively; the reference drug, metoclopramide (MCP; 30 mg/kg), produced ~ 48.83% reduction (P < 0.05). ZO-ActFr reduced (P < 0.05 - 0.001) 5-hydroxytryptamine (5HT) concentration in the area postrema, brain stem and intestine at 3(rd) hour of cisplatin administration, while at the 18(th) hour ZO treatments attenuated the dopamine upsurge (P < 0.001) caused by cisplatin in the area postrema and 5HT concentration (P < 0.01 - 0.001) in the brain stem and intestine. ZO treatments alone did not altered the basal neurotransmitters and their metabolites in the brain areas and intestine. CONCLUSION: The behavioral study verify the antiemetic profile of ZO against cisplatin induced emesis in the pigeon, where central and peripheral neural evidences advocate the involvement of serotonergic mechanism at initial time point (3(rd) hr), while the later time point (18(th) hr) is associated with serotonergic and dopaminergic component in the mediation of its antiemetic effect.


Assuntos
Antieméticos/farmacologia , Cisplatino/efeitos adversos , Dopamina/metabolismo , Fitoterapia , Serotonina/metabolismo , Vômito/tratamento farmacológico , Zingiber officinale , Animais , Antieméticos/uso terapêutico , Antineoplásicos/efeitos adversos , Comportamento Animal , Columbidae , Feminino , Masculino , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Vômito/induzido quimicamente , Vômito/metabolismo
12.
World J Microbiol Biotechnol ; 31(11): 1699-710, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26250549

RESUMO

The growing demands of bioenergy has led to the emphasis on novel cellulases to improve efficiency of biodegradation process of plant biomass. Therefore, a thermostable cellulolytic gene (CenC) with 3675 bp was cloned from Clostridium thermocellum and over-expressed in Escherichia coli strain BL21 CodonPlus. It was attested that CenC belongs to glycoside hydrolase family 9 (GH9) with four binding domains, a processive endoglucanase. CenC was purified to homogeneity, producing a single band on SDS-PAGE corresponding to 137.11 kDa, by purification steps of heat treatment combined with ion-exchange chromatography. Purified enzyme displayed optimal activity at pH 6.0 and 70 °C. CenC had a half-life of 24 min at 74 °C, was stable up to 2 h at 60 °C and over a pH range of 5.5-7.5. Enzyme showed high affinity towards various substrates and processively released cellobiose from cellulosic substrates. It efficiently hydrolyzed carboxymethyl cellulose (30 U/mg), ß-Glucan Barley (94 U/mg); also showed activity towards p-nitrophenyl-ß-D-cellobioside (18 U/mg), birchwood xylan (19 U/mg), beechwood xylan (17.5 U/mg), avicel (9 U/mg), whatman filter paper (11 U/mg) and laminarin (3.3 U/mg). CenC exhibited Km, Vmax, Kcat, Vmax Km(-1) and Kcat Km(-1) of 7.14 mM, 52.4 µmol mg(-1) min(-1), 632.85 s(-1), 7.34 min(-1) and 88.63, respectively used CMC as substrate. Recombinant CenC saccharified pretreated wheat straw and bagasse to 5.12 and 7.31%, respectively at pH 7.0 and 45 °C after 2 h incubation. Its thermostability, high catalytic efficiency and independence of inhibitors make CenC enzyme an appropriate candidate for industrial applications and cost-effective saccharification process.


Assuntos
Celulase/química , Celulase/metabolismo , Clonagem Molecular/métodos , Clostridium thermocellum/enzimologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Celulase/genética , Clostridium thermocellum/genética , Estabilidade Enzimática , Escherichia coli/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Temperatura
13.
Food Chem ; 460(Pt 3): 140626, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39128363

RESUMO

Glucose-derived acids for the further production of value-added medicine, food additives, and polymers, will promote lignocellulosic biomass biorefinery industry. In response to the diversity and complexity, a new method was established by employing high performance anion exchange chromatography (HPAEC) coupled with a CarboPac™ PA200 column, for the precise and fast determination of glucose, gluconic acid, glucuronic acid, 2-ketogluconic acid, 5-ketogluconic acid and glucaric acid. Based on the analysis of tiny varieties in retention behavior, a gradient elution mode was designed and optimized for the quantitative and qualitative analysis. The protocol displayed acceptable linearity (R2 ≥ 0.995), commendable average recovery rate (95.28% âˆ¼ 99.89%), satisfactory precision (RSD% ≤ 1.5%), and sufficient resolution (R > 6). Additionally, this method was successfully applied to the high-value biorefining process, which confirmed the practicability and accuracy. The results demonstrated that HPAEC has good detection performance for glucose and its derivative acids, and provide key identification technical support for the high-value utilization of lignocellulose.


Assuntos
Biomassa , Glucose , Cromatografia por Troca Iônica/métodos , Glucose/análise , Glucose/química , Cromatografia Líquida de Alta Pressão/métodos , Lignina/química , Ácidos/análise , Ácidos/química
14.
Int J Biol Macromol ; 265(Pt 1): 130993, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38508567

RESUMO

Hemicellulases are enzymes that hydrolyze hemicelluloses, common polysaccharides in nature. Thermophilic hemicellulases, derived from microbial strains, are extensively studied as natural biofuel sources due to the complex structure of hemicelluloses. Recent research aims to elucidate the catalytic principles, mechanisms and specificity of hemicellulases through investigations into their high-temperature stability and structural features, which have applications in biotechnology and industry. This review article targets to serve as a comprehensive resource, highlighting the significant progress in the field and emphasizing the vital role of thermophilic hemicellulases in eco-friendly catalysis. The primary goal is to improve the reliability of hemicellulase enzymes obtained from thermophilic bacterial strains. Additionally, with their ability to break down lignocellulosic materials, hemicellulases hold immense potential for biofuel production. Despite their potential, the commercial viability is hindered by their high enzyme costs, necessitating the development of efficient bioprocesses involving waste pretreatment with microbial consortia to overcome this challenge.


Assuntos
Bactérias , Biocombustíveis , Reprodutibilidade dos Testes , Glicosídeo Hidrolases/química , Lignina
15.
Mol Biotechnol ; 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461181

RESUMO

Esterases are hydrolases that contribute to the hydrolysis of ester bonds into both water-soluble acyl esters and emulsified glycerol-esters containing short-chain acyl groups. They have garnered significant attention from biotechnologists and organic chemists due to their immense commercial value. Esterases, with their diverse and significant properties, have become highly sought after for various industrial applications. Synthesized ubiquitously by a wide range of living organisms, including animals, plants, and microorganisms, these enzymes have found microbial esterases to be the preferred choice in industrial settings. The cost-effective production of microbial esterases ensures higher yields, unaffected by seasonal variations. Their applications span diverse sectors, such as food manufacturing, leather tanneries, paper and pulp production, textiles, detergents, cosmetics, pharmaceuticals, biodiesel synthesis, bioremediation, and waste treatment. As the global trend shifts toward eco-friendly and sustainable practices, industrial processes are evolving with reduced waste generation, lower energy consumption, and the utilization of biocatalysts derived from renewable and unconventional raw materials. This review explores the background, structural characteristics, thermostability, and multifaceted roles of bacterial esterases in crucial industries, aiming to optimize and analyze their properties for continued successful utilization in diverse industrial processes. Additionally, recent advancements in esterase research are overviewed, showcasing novel techniques, innovations, and promising areas for further exploration.

16.
Front Bioeng Biotechnol ; 12: 1441075, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39108598

RESUMO

The persistent expansion in world energy and synthetic compounds requires the improvement of renewable alternatives in contrast to non-sustainable energy wellsprings. Lignocellulose is an encouraging feedstock to be utilized in biorefineries for its conversion into value-added products, including biomaterials, biofuels and several bio-based synthetic compounds. Aside from all categories, biofuel, particularly bioethanol is the most substantial fuel derived from lignocellulosic biomass and can be obtained through microbial fermentation. Generally, extreme settings are required for lignocellulosic pretreatment which results in the formation of inhibitors during biomassdegradation. Occasionally, lignin polymers also act as inhibitors and are left untreated during the pretreatment, engendering inefficient hydrolysis. The valorization of lignocellulosic biomass by laccases can be viewed as a fundamental trend for improving bioethanol production. However, one of the main obstacles for developing commercially viable biofuel industries is the cost of enzymes, which can be resolved by utilizing laccases derived from microbial sources. Microbial laccases have been considered an exceptionally integral asset for delignification and detoxification of pretreated LCB, which amplify the resultant fermentation and saccharification processes. This review provides a summary of microbial laccases and their role in valorizing LCB to bioethanol, compelling enthralling applications in bio-refining industries all across the globe.

17.
J Int Soc Prev Community Dent ; 14(4): 261-277, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39380926

RESUMO

Aim: This study aims to conduct a comprehensive analysis and scientometric evaluation of the top 100 most cited publications in the field of implant prosthodontics, authored by individuals affiliated with nations of the Middle East and North Africa (MENA) region. Materials and Methods: In October 2023, the 100 most cited articles were gathered from the Web of Science database using the bibliometric research technique. The analysis was conducted on bibliometric indicators, including the distribution of articles over time, authorship, design of study, field of study, nature of research, contribution from various countries in MENA, international research collaboration, and most frequently used keywords by authors. Chi-square and one-way analysis of variance were used for statistical analysis. VOSviewer software was used to analyze the bibliometric network for co-occurrence among countries, coauthors, and common keywords. Results: The results revealed that the top 100 most cited articles from MENA countries on the topic of implant prosthodontics, published between 1995 and 2020, had received an average of 73.31 citations each. About one-third of the papers were published in the top 4 journals. The journal with the most published articles was Clinical Oral Implant Research, followed by the International Journal of Oral & Maxillofacial Implants, the International Journal of Prosthodontics, and the Journal of Oral and Maxillofacial Surgery. Saudi Arabia had the distinction of producing the greatest number of highly cited papers. The co-occurrence network analysis using VOSviewer software identified 10-15 related clusters. Research studies with multiple authors received significantly more citations (P < 0.05). Significant relationships were observed between the number of citations and journal type (open access vs. non-open access; P < 0.05), and also articles published in dental journals received the most citations and were statistically significant (P = 0.001). Conclusion: Over the last decade, there has been a significant surge in research related to implant prosthodontics. Among the countries in the MENA region, Saudi Arabia has distinguished itself by leading in terms of overall research output. This resource would benefit academicians, clinicians, and researchers in prosthodontics, oral surgery, and periodontic specialties of dentistry.

18.
Heliyon ; 10(12): e32031, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38988512

RESUMO

The evaluation of publication growth is a vital indicator to assess any branch of knowledge. The present study aimed to investigate the Scopus-indexed publications on orthodontics produced by the Arab League Nations in the last two decades (2002-2021). Quantitative research method based on bibliometric analysis has been used and the meta-data for the study was retrieved from Elsevier's Scopus database on November 14, 2022. The bibliographic description of all types of literature published on orthodontics from 2002 to 2021 by the authors affiliated with the Arab countries has been downloaded. The selected bibliometric indicators of the data were analyzed by using Microsoft Excel, VOSviewer and SPSS software. The Arab League Nations contributed 5.02 % to global orthodontic research. This segment has demonstrated an amazing escalation of documents from a global perspective between 2002 and 2021 from 1.24 % to 10.94 %. Slightly more than 60 % of documents were published during the last five years of study (2017-2021). The highest number of documents (41 %) was produced by Saudi Arabia, whereas documents contributed by Jordan gained the maximum citation impact. The majority of collaboration was done with the United States, but documents produced in collaboration with Turkey gained the highest citation impact. The paper highlighted that the share of Arab League Nations in orthodontic research has been growing, and Saudi Arabia emerged as the most productive country. The constructive evolution of orthodontic literature with international collaboration display an ambitious approach by Arab countries.

19.
BMC Complement Altern Med ; 13: 197, 2013 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-23895558

RESUMO

BACKGROUND: The present study describes the tracheorelaxant and anti-inflammatory effects of Polygonatum verticillatum which may support its medicinal use in hyperactive airway complaints and inflammatory disorders. METHODS: The tracheorelaxant activity of crude extract of the rhizomes of P. verticillatum (PR) was assessed in isolated guinea-pig tracheal tissues immersed in tissue organ bath filled with Tyrode's solution and a continuous supply of carbogen gas (95% O2 and 5% CO2). The contractile and relaxant responses of the tissue were measured using isometric transducers coupled with Power-Lab data acquisition system. The anti-inflammatory effect was evaluated in carrageenan-induced rat paw edema model, while the lipoxygenase inhibitory activity was performed in the in-vitro assay. Various chromatographic and spectroscopic techniques were used for the isolation and characterization of pure molecules. RESULTS: In isolated guinea-pig tracheal preparations, PR caused complete inhibition of the high K+ (80 mM) and carbachol-induced contractions however, it was more potent against K+ than CCh, similar to verapamil. Pretreatment of the tissue with PR, displaced the Ca2+ concentration-response curves to the right, similar to that induced by verapamil, indicating the presence of Ca2+ channel blocking like activity. When tested on carrageenan-induced rat paw edema, PR demonstrated a marked reduction in edema with 65.22% protection at 200 mg/kg, similar to aspirin. In the in-vitro assay, PR showed lipoxygenase inhibitory activity (IC50: 102 ± 0.19 µg/mL), similar to baicalein. Bioactivity-guided fractionation led to the isolation of 2-hydroxybenzoic acid and ß-sitosterol. CONCLUSIONS: These results indicate that the plant possesses tracheorelaxant, mediated possibly through a Ca2+ channel blockade mechanism, and anti-inflammatory activities, which may explain the medicinal use of this plant in airway disorders and inflammation.


Assuntos
Anti-Inflamatórios/uso terapêutico , Contração Muscular/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/uso terapêutico , Polygonatum/química , Doenças Respiratórias , Traqueia/efeitos dos fármacos , Animais , Anti-Inflamatórios/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/uso terapêutico , Carbacol , Carragenina , Edema/induzido quimicamente , Edema/tratamento farmacológico , Feminino , Cobaias , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/patologia , Masculino , Músculo Liso/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Doenças Respiratórias/tratamento farmacológico , Rizoma/química , Ácido Salicílico/isolamento & purificação , Ácido Salicílico/farmacologia , Ácido Salicílico/uso terapêutico , Sitosteroides/isolamento & purificação , Sitosteroides/farmacologia , Sitosteroides/uso terapêutico , Verapamil/farmacologia
20.
Phytother Res ; 27(9): 1288-92, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23109174

RESUMO

Polygonatum verticillatum is commonly used for the treatment of asthma and inflammation. The current study was aimed to scrutinize the pharmacological profile of methanolic extract of the aerial parts (PA). Isolated tracheal preparations were used for the evaluation of bronchodilatory activity, whilst the in vivo carrageenan-induced paw oedema test and an in vitro lipoxygenase (LOX) inhibitory assay were used for the assessment of the anti-inflammatory profile of PA. When tested against carbachol and K⁺ (80 mM)-induced contractions, PA caused complete inhibition of isolated rabbit tracheal preparations in a dose-dependent mode, similar to verapamil. While elucidating possible mechanism, PA shifted the Ca²âº concentration-response curves to the right, analogous to that produced by verapamil, confirming a Ca²âº channel blocker-like activity. PA provoked profound reduction in paw oedema with a maximum protection of 60.87% at 200 mg/kg i.p. in a dose-dependent manner which was augmented by its prominent LOX inhibitory activity (IC50 : 125 µg/mL). These findings authenticated its therapeutic potential in the treatment of asthmatic and inflammatory conditions.


Assuntos
Anti-Inflamatórios/farmacologia , Broncodilatadores/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Inibidores de Lipoxigenase/farmacologia , Extratos Vegetais/farmacologia , Polygonatum/química , Animais , Carbacol/efeitos adversos , Carragenina/efeitos adversos , Edema/tratamento farmacológico , Feminino , Técnicas In Vitro , Inflamação/tratamento farmacológico , Masculino , Componentes Aéreos da Planta/química , Coelhos , Ratos , Ratos Wistar , Traqueia/efeitos dos fármacos , Verapamil/farmacologia
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