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In 2019, a worldwide pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged. SARS-CoV-2 is the deadly microorganism responsible for coronavirus disease 2019 (COVID-19), which has caused millions of deaths and irreversible health problems worldwide. To restrict the spread of SARS-CoV-2, accurate detection of COVID-19 is essential for the identification and control of infected cases. Although recent detection technologies such as the real-time polymerase chain reaction delivers an accurate diagnosis of SARS-CoV-2, they require a long processing duration, expensive equipment, and highly skilled personnel. Therefore, a rapid diagnosis with accurate results is indispensable to offer effective disease suppression. Nanotechnology is the backbone of current science and technology developments including nanoparticles (NPs) that can biomimic the corona and develop deep interaction with its proteins because of their identical structures on the nanoscale. Various NPs have been extensively applied in numerous medical applications, including implants, biosensors, drug delivery, and bioimaging. Among them, point-of-care biosensors mediated with gold nanoparticles (GNPSs) have received great attention due to their accurate sensing characteristics, which are widely used in the detection of amino acids, enzymes, DNA, and RNA in samples. GNPS have reconstructed the biomedical application of biosensors because of its outstanding physicochemical characteristics. This review provides an overview of emerging trends in GNP-mediated point-of-care biosensor strategies for diagnosing various mutated forms of human coronaviruses that incorporate different transducers and biomarkers. The review also specifically highlights trends in gold nanobiosensors for coronavirus detection, ranging from the initial COVID-19 outbreak to its subsequent evolution into a pandemic.
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Heat shock proteins (HSPs) are developmentally conserved families of protein found in both prokaryotic and eukaryotic organisms. HSPs are engaged in a diverse range of physiological processes, including molecular chaperone activity to assist the initial protein folding or promote the unfolding and refolding of misfolded intermediates to acquire the normal or native conformation and its translocation and prevent protein aggregation as well as in immunity, apoptosis, and autophagy. These molecular chaperonins are classified into various families according to their molecular size or weight, encompassing small HSPs (e.g., HSP10 and HSP27), HSP40, HSP60, HSP70, HSP90, and the category of large HSPs that include HSP100 and ClpB proteins. The overexpression of HSPs is induced to counteract cell stress at elevated levels in a variety of solid tumors, including anticancer chemotherapy, and is closely related to a worse prognosis and therapeutic resistance to cancer cells. HSPs are also involved in anti-apoptotic properties and are associated with processes of cancer progression and development, such as metastasis, invasion, and cell proliferation. This review outlines the previously mentioned HSPs and their significant involvement in diverse mechanisms of tumor advancement and metastasis, as well as their contribution to identifying potential targets for therapeutic interventions.
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The development of multidrug resistance (MDR) against chemotherapeutic agents has become a major impediment in cancer therapy. Understanding the underlying mechanism behind MDR can guide future treatment for cancer with better therapeutic outcomes. Recent studies evidenced that crossroads interaction between the heat shock proteins (HSP) and inflammatory responses under the tumor microenvironment plays a pivotal role in modulating drug responsiveness and drug resistance through a complex cytological process. This review aims to investigate the interrelationship between inflammation and HSP in acquiring multiple drug resistance and investigate strategies to overcome the drug resistance to improve the efficacy of cancer treatment. HSP plays a dual regulatory effect as an immunosuppressive and immunostimulatory agent, involving the simultaneous blockade of multiple signaling pathways in acquiring MDR. For example, HSP27 shows biological effects on monocytes by causing IL10 and TNFα secretion and blocking monocyte differentiation to normal dendritic cells and tumor-associated macrophages to promote cancer progression and chemoresistance. Thus, the HSP function and immune-checkpoint release modalities provide a therapeutic target for a therapeutically beneficial approach for enhancing anti-tumor immune responses. The interconnection between inflammation and HSP, along with the tumor microenvironment in acquiring drug resistance, has become crucial for rationalizing the effect of HSP immunomodulatory activity with immune checkpoint blockade. This relationship can overcome drug resistance and assist in the development of novel combinatorial cancer immunotherapy in fighting cancer with decreasing mortality rates.
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Cancer is one of the most dangerous health problems in the millennium and it is the third foremost human cause of death in the universe. Traditional cancer treatments face several disadvantages and cannot often afford adequate outcomes. It has been exhibited that the outcome of several therapies can be improved when associated with nanostructures. In addition, a modern tendency is being developed in cancer therapy to convert single-modal into multi-modal therapies with the help of existing various nanostructures. Among them, gold is the most successful nanostructure for biomedical applications due to its flexibility in preparation, stabilization, surface modifications, less cytotoxicity, and ease of bio-detection. In the past few decades, gold-based nanomaterials rule cancer treatment applications, currently, gold nanostructures were the leading nanomaterials for synergetic cancer therapies. In this review article, the synthesis, stabilization, and optical properties of gold nanostructures have been discussed. Then, the surface modifications and targeting mechanisms of gold nanomaterials will be described. Recent signs of progress in the application of gold nanomaterials for synergetic cancer therapies such as photodynamic and photo-thermal therapies in combination with other common interventions such as radiotherapy, chemotherapy, and will be reviewed. Also, a summary of the pharmacokinetics of gold nanostructures will be delivered. Finally, the challenges and outlooks of the gold nanostructures in the clinics for applications in cancer treatments are debated.
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The Silk sericin protein was conjugated with magnesium oxide (MgO) nanoparticles to form SS-MgO-NPs . UV, XRD, FTIR, SEM, DLS, and EDX were used to confirm the formation of SS-MgO-NPs. The absorption band of SS-MgO-NPs using UV-visible spectra was observed at 310 nm, with an average size of the nanoparticles was 65-88 nm analyzed from DLS. The presence of alcohol, CN, and CC, alkanes, alkenes, and cis alkenes, in silk sericin, is confirmed by FT-IR and may act as a stabilizing agent. Later SS-MgO-NPs were evaluated for antioxidant, antibacterial, anti-biofilm, ,anti-aging, and anticancer properties. The SS-MgO-NPs inhibited the formation of biofilm of Pseudomonas aeruginosa and Bacillus cereus. The blood compatibility of SS-MgO-NPs, delaying coagulation was observed using human, blood, and goat blood samples. The SS-MgO-NPs exhibited significant anticancer activity on MCF-7 (IC50 207.6 µg/mL) cancer cell lines. Correspondingly, SS-MgO-NPs demonstrated dose-dependent inhibition of the enzymes in the following order collagenase > elastase > tyrosinase > hyaluronidase, with IC50 values of 75.3, 85.3, 133.6, and 156.3 µgmL-1, respectively. This exhibits the compoundposses anti-aging properties. So, in in vitro settings, SS-MgO-NPs can be used as an antibacterial, anti-aging, and anticancer agent. Additionally, in vivo research is necessary to validate its therapeutic applications.
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Nanopartículas del Metal , Nanopartículas , Sericinas , Humanos , Antibacterianos/farmacología , Antioxidantes/farmacología , Óxido de Magnesio/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , BiopelículasRESUMEN
Regenerative medicine has received potential attention around the globe, with improving cell performances, one of the necessary ideas for the advancements of regenerative medicine. It is crucial to enhance cell performances in the physiological system for drug release studies because the variation in cell environments between in vitro and in vivo develops a loop in drug estimation. On the other hand, tissue engineering is a potential path to integrate cells with scaffold biomaterials and produce growth factors to regenerate organs. Scaffold biomaterials are a prototype for tissue production and perform vital functions in tissue engineering. Silk fibroin is a natural fibrous polymer with significant usage in regenerative medicine because of the growing interest in leftovers for silk biomaterials in tissue engineering. Among various natural biopolymer-based biomaterials, silk fibroin-based biomaterials have attracted significant attention due to their outstanding mechanical properties, biocompatibility, hemocompatibility, and biodegradability for regenerative medicine and scaffold applications. This review article focused on highlighting the recent advancements of 3D printing in silk fibroin scaffold technologies for regenerative medicine and tissue engineering.
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The world is facing a global financial loss and health effects due to food quality adulteration and contamination, which are seriously affecting human health. Synthetic colors, flavors, and preservatives are added to make food more attractive to consumers. Therefore, food safety has become one of the fundamental needs of mankind. Due to the importance of food safety, the world is in great need of developing desirable and accurate methods for determining the quality of food. In recent years, the electrochemical methods have become more popular, due to their simplicity, ease in handling, economics, and specificity in determining food safety. Common food contaminants, such as pesticides, additives, and animal drug residues, cause foods that are most vulnerable to contamination to undergo evaluation frequently. The present review article discusses the electrochemical detection of the above food contaminants using different carbon nanomaterials, such as carbon nanotubes (CNTs), graphene, ordered mesoporous carbon (OMC), carbon dots, boron doped diamond (BDD), and fullerenes. The voltammetric methods, such as cyclic voltammetry (CV) and differential pulse voltammetry (DPV), have been proven to be potential methods for determining food contaminants. The use of carbon-based electrodes has the added advantage of electrochemically sensing the food contaminants due to their excellent sensitivity, specificity, large surface area, high porosity, antifouling, and biocompatibility.
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Nanoestructuras , Nanotubos de Carbono , Humanos , Nanotubos de Carbono/química , Inocuidad de los Alimentos , Técnicas Electroquímicas , ElectrodosRESUMEN
The potentiality of nanomedicine in the cancer treatment being widely recognized in the recent years. In the present investigation, the synergistic effects of chitosan-modified selenium nanoparticles loaded with paclitaxel (PTX-chit-SeNPs) were studied. These selenium nanoparticles were tested for drug release analysis at a pH of 7.4 and 5.5, and further characterized using FTIR, DLS, zeta potential, and TEM to confirm their morphology, and the encapsulation of the drug was carried out using UPLC analysis. Quantitative evaluation of anti-cancer properties was performed via MTT analysis, apoptosis, gene expression analysis, cell cycle arrest, and over-production of ROS. The unique combination of phytochemicals from the seed extract, chitosan, paclitaxel, and selenium nanoparticles can be effectively utilized to combat cancerous cells. The production of the nanosystem has been demonstrated to be cost-effective and have unique characteristics, and can be utilized for improving future diagnostic approaches.
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Quitosano , Nanopartículas , Selenio , Neoplasias del Cuello Uterino , Femenino , Humanos , Paclitaxel/química , Selenio/química , Quitosano/química , Neoplasias del Cuello Uterino/tratamiento farmacológico , Línea Celular Tumoral , Nanopartículas/químicaRESUMEN
Carbon nanodots (CNDs) are advanced nanomaterials with a size of 2-10 nm and are considered zero-dimensional carbonaceous materials. CNDs have received great attention in the area of cancer theranostics. The majority of review articles have shown the improvement of CNDs for use in cancer therapy and bioimaging applications. However, there is a minimal number of consolidated studies on the currently developed doped CNDs that are used in various ways in cancer therapies. Hence, in this review, we discuss the current developments in different types of heteroatom elements/metal ion-doped CNDs along with their preparations, physicochemical and biological properties, multimodal-imaging, and emerging applications in image-guided photodynamic therapies for cancer.
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Despite the discovery and development of an array of antimicrobial agents, multidrug resistance poses a major threat to public health and progressively increases mortality. Recently, several studies have focused on developing promising solutions to overcome these problems. This has led to the development of effective alternative methods of controlling antibiotic-resistant pathogens. The use of antimicrobial agents in combination can produce synergistic effects if each drug invades a different target or signaling pathway with a different mechanism of action. Therefore, drug combinations can achieve a higher probability and selectivity of therapeutic responses than single drugs. In this systematic review, we discuss the combined effects of different antimicrobial agents, such as plant extracts, essential oils, and nanomaterials. Furthermore, we review their synergistic interactions and antimicrobial activities with the mechanism of action, toxicity, and future directions of different antimicrobial agents in combination. Upon combination at an optimum synergistic ratio, two or more drugs can have a significantly enhanced therapeutic effect at lower concentrations. Hence, using drug combinations could be a new, simple, and effective alternative to solve the problem of antibiotic resistance and reduce susceptibility.
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In the current study, the photocatalytic activity of bimetallic ZnO-CuO hetero-nanocomposite was evaluated and compared with the monometallic ZnO and CuO nanoparticles using 4-nitroaniline (4-NA) and methyl orange (MO). Bimetallic ZnO-CuO hetero-nanocomposite, ZnO, and CuO nanostructure were synthesized utilizing leaf extract of Aegle marmelos and characterized by transmission electron microscopy, X-ray diffraction, and XPS. Benefiting from the p-n heterostructures formation, bimetallic ZnO-CuO hetero-nanocomposite exhibits an excellent photocatalytic activity against 4-NA as well as MO compared to pure ZnO and CuO. In particular, bimetallic ZnO-CuO hetero-nanocomposite expressed the highest photocatalytic activity by reducing 90% of 4-NA in 20 min and by degrading 96% of MO in 10 min, whereas 65% reduction of 4-NA in 30 min and 93% degradation of MO in 45 min was exhibited by CuO and 48% reduction of 4-NA in 30 min and 98% degradation of MO in 50 min was exhibited by ZnO. Moreover, bimetallic ZnO-CuO hetero-nanocomposite maintains excellent photocatalytic activity even after five cycles indicating its stability as photocatalyst and reusability. Based on the experimental findings, bimetallic ZnO-CuO hetero-nanocomposite could be used as a photocatalyst for wastewater treatment with excellent regeneration efficiency.
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Aegle , Nanocompuestos , Óxido de Zinc , Compuestos de Anilina , Compuestos Azo , Catálisis , Nanocompuestos/química , Extractos Vegetales , Óxido de Zinc/químicaRESUMEN
Polymeric nanocomposites have received significant attention in both scientific and industrial research in recent years. The demand for new methods of food preservation to ensure high-quality, healthy foods with an extended shelf life has increased. Packaging, a crucial feature of the food industry, plays a vital role in satisfying this demand. Polymeric nanocomposites exhibit remarkably improved packaging properties, including barrier properties, oxygen impermeability, solvent resistance, moisture permeability, thermal stability, and antimicrobial characteristics. Bio-based polymers have drawn considerable interest to mitigate the influence and application of petroleum-derived polymeric materials and related environmental concerns. The integration of nanotechnology in food packaging systems has shown promise for enhancing the quality and shelf life of food. This article provides a general overview of bio-based polymeric nanocomposites comprising polymer matrices and inorganic nanoparticles, and describes their classification, fabrication, properties, and applications for active food packaging systems with future perspectives.
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The development of food-borne and infectious diseases has increased globally at an anomalous rate and is combined with emerging social and economic problems. This highlights the need for new and improved antibacterial agents with novel and different mechanisms of action at regular intervals. Some chemical or artificial food additives are considered harmful if they are used beyond their permissible levels. Today, consumers are demanding alternative, green, safer, and natural food additives to increase the shelf life of food. Essential oils (EOs) are concentrated liquid mixtures of volatile compounds with antioxidant and antibacterial properties that can be used as natural, eco-friendly, renewable, and cost-effective additives. The use of combinations of different EOs and their components is a promising strategy to increase the synergistic and additive effects of EOs in foods. In this article, we review the recent literature on EOs concerning the chemical constituents, extraction methods, antioxidant and antibacterial activities, and their mechanisms of action. Additionally, we discuss the synergistic interaction of different EOs and their components, challenges, and future directions of EOs as natural food preservatives, with special emphasis on shelf life extension and applications in the packaging of food products.
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Antibacterianos/farmacología , Antioxidantes/farmacología , Embalaje de Alimentos , Aceites Volátiles/farmacología , Sinergismo Farmacológico , Modelos Biológicos , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificaciónRESUMEN
Over the last century, the demand for food resources has been continuously increasing with the rapid population growth. Therefore, it is critically important to adopt sustainable farming practices that can enhance crop production without the excessive use of fertilizers. In this regard, there is a growing interest in the use of nanomaterials for improving plant nutrition as an alternative to traditional chemical or mineral fertilizers. Using this technology, the efficiency of micro- and macro-nutrients in plants can increase. Various nanomaterials have been successfully applied in agricultural production, compared to conventional fertilizers. Among the major plant nutrients, phosphorus (P) is the least accessible since most farmlands are frequently P deficient. Hence, P use efficiency should be maximized to conserve the resource base and maintain agricultural productivity. This review summarizes the current research and the future possibilities of nanotechnology in the biofortification of plant nutrition, with a focus on P fertilizers. In addition, it covers the challenges, environmental impacts, and toxic effects that have been explored in the area of nanotechnology to improve crop production. The potential uses and benefits of nanoparticle-based fertilizers in precision and sustainable agriculture are also discussed.
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Recently, infectious diseases caused by bacterial pathogens have become a major cause of morbidity and mortality globally due to their resistance to multiple antibiotics. This has triggered initiatives to develop novel, alternative antimicrobial materials, which solve the issue of infection with multidrug-resistant bacteria. Nanotechnology using nanoscale materials, especially multimetallic nanoparticles (NPs), has attracted interest because of the favorable physicochemical properties of these materials, including antibacterial properties and excellent biocompatibility. Multimetallic NPs, particularly those formed by more than two metals, exhibit rich electronic, optical, and magnetic properties. Multimetallic NP properties, including size and shape, zeta potential, and large surface area, facilitate their efficient interaction with bacterial cell membranes, thereby inducing disruption, reactive oxygen species production, protein dysfunction, DNA damage, and killing potentiated by the host's immune system. In this review, we summarize research progress on the synergistic effect of multimetallic NPs as alternative antimicrobial agents for treating severe bacterial infections. We highlight recent promising innovations of multimetallic NPs that help overcome antimicrobial resistance. These include insights into their properties, mode of action, the development of synthetic methods, and combinatorial therapies using bi- and trimetallic NPs with other existing antimicrobial agents.
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Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Infecciones Bacterianas/tratamiento farmacológico , Nanopartículas del Metal/administración & dosificación , Metales/química , Animales , Antiinfecciosos/administración & dosificación , Antiinfecciosos/química , Infecciones Bacterianas/microbiología , Humanos , Nanopartículas del Metal/químicaRESUMEN
Over the past few decades, many pathogenic bacteria have become resistant to existing antibiotics, which has become a threat to infectious disease control worldwide. Hence, there has been an extensive search for new, efficient, and alternative sources of antimicrobial agents to combat multidrug-resistant pathogenic microorganisms. Numerous studies have reported the potential of both essential oils and metal/metal oxide nanocomposites with broad spectra of bioactivities including antioxidant, anticancer, and antimicrobial attributes. However, only monometallic nanoparticles combined with essential oils have been reported on so far with limited data. Bi- and tri-metallic nanoparticles have attracted immense attention because of their diverse sizes, shapes, high surface-to-volume ratios, activities, physical and chemical stability, and greater degree of selectivity. Combination therapy is currently blooming and represents a potential area that requires greater attention and is worthy of future investigations. This review summarizes the synergistic effects of essential oils with other antimicrobial combinations such as mono-, bi-, and tri-metallic nanocomposites. Thus, the various aspects of this comprehensive review may prove useful in the development of new and alternative therapeutics against antibiotic resistant pathogens in the future.
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Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Nanopartículas del Metal/química , Nanocompuestos/química , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Antioxidantes/farmacología , Sinergismo Farmacológico , Humanos , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificaciónRESUMEN
BACKGROUND: Ipomoea batatas (L.) Lam.(Ib) has high content of various beneficial nutrients which helps in improving and maintaining human health. It is well known as a functional food and also a valuable source of unique natural products. It contains various phenolic and flavonoid bioactive compounds. METHODS: In this study, using the outer peel of two varieties of Ib : Korean red skin sweet potato and Korean pumpkin sweet potato, silver nanoparticles (AgNPs) were synthesized (termed Ib1-AgNps and Ib2-AgNps), respectively. Characterization of Ib1-AgNPs and Ib2-AgNPs was carried out through scanning electron microscopy, Fourier-transform infrared (FT-IR) spectroscopy, energy-dispersive X-ray analysis, X-ray powder diffraction and UV-Vis spectroscopy. Further, the bio-potential of the synthesized AgNPs was investigated by antidiabetic (α-glucosidase assay), antioxidant (free radical scavenging assays), antibacterial (disc diffusion method) and cytotoxicity assays (cell viability against HepG2 cells). RESULTS: FT-IR spectroscopy revealed the contribution of bioactive compounds existing in Ib1 and Ib2 extracts, in the biosynthesis and equilibrium of the AgNPs. Although the Ib2-AgNPs had a higher atomic percentage of Ag in comparison with Ib1-AgNPs, in the antidiabetic assay, the inhibition percentage of α-glucosidase was higher for AgNPs of Ib1 than Ib2, at all three concentrations examined. From the cytotoxicity results, HepG2 cancer cells were more sensitive to the Ib1-AgNPs in comparison to the Ib2-AgNPs-treated HepG2 cells. The antioxidant prospective was higher in Ib2-AgNPs than Ib1-AgNPs. Moreover, the Ib2-AgNPs showed inhibitory action against all five tested pathogenic bacteria, producing an inhibition zone of 8.74-11.52 mm while Ib1-AgNPs had an inhibitory effect on four of them, with an 8.67-11.23 (mm) inhibition zone. CONCLUSIONS: Overall, the results concluded that the Ib2-AgNPs exhibited relatively higher functional activity than Ib1-AgNPs, which might be credited to the greater abundance of bioactive compounds existing in Ib2 extract that acted as reducing as well as capping agents in the synthesis of Ib2-AgNPs. Overall, the current study highlights a novel cost-effective and eco-friendly AgNPs synthesis using food waste peels with biocompatibility and could be potentially utilized in biomedical and pharmaceutical industries.
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Antibacterianos/farmacología , Antioxidantes/farmacología , Ipomoea batatas/química , Nanopartículas del Metal/química , Plata/farmacología , Bacterias/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Células Hep G2 , Humanos , Hipoglucemiantes/farmacología , Concentración 50 Inhibidora , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X , alfa-Glucosidasas/metabolismoRESUMEN
INTRODUCTION: Novel approaches for the synthesis of gold nanoparticles (AuNPs) are of great importance due to its vast spectrum of applications in diverse fields, including medical diagnostics and therapeutics. Te presented study reports the successful AuNPs' synthesis using Artocarpus heterophyllus Lam. extract, and provides detailed characterization and evaluation of its antibacterial potential. OBJECTIVE: The aim was to develop a cost-effective and environmentally friendly synthesis method of gold nanoparticles using aqueous fruit extract of Artocarpus heterophyllus Lam. as a reducing and capping agent, which has proven activity against human pathogens, such as microbial species E.coli and Streptobacillus sps. MATERIALS AND METHOD: Characterizations were carried out using ultraviolet-visible (UV-Vis) spectrophotometry, scanning electron microscopy (SEM), energy dispersive X-ray and Fourier-Transform infra-red spectroscopy (FT-IR). RESULTS: SEM images showed the formation of gold nanoparticles with an average size of 20-25 nm. Spectra collected while infra-red analysis contained broad peaks in ranges from 4000-400 cm -1 . CONCLUSIONS: It can be concluded that the fruit of Artocarpus heterophyllus Lam. can be good source for synthesis of gold nanoparticles which showed antimicrobial activity against investigated microbes, in particul E. coli, and Streptobacillus. An important outcome of this study will be the development of value-added products from the medicinal plant Artocarpus heterophyllus Lam. for the biomedical and nanotechnology-based industries.
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Artocarpus/química , Escherichia coli/efectos de los fármacos , Oro/farmacología , Nanopartículas del Metal/química , Nanotecnología/métodos , Extractos Vegetales/química , Streptobacillus/efectos de los fármacos , Materiales Biocompatibles/farmacología , Frutas/química , Oxidación-ReducciónRESUMEN
An efficient one-pot synthesis of various 2,3-dihydroquinazolin-4(1H)-one derivatives was accomplished using Cu(OTf)2-catalyzed multi-component reactions between isatoic anhydride, ketones, and amines. The method has several significant advantages; mild reaction conditions, easy handling, and efficiency of catalyst.
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Cobre/química , Mesilatos/química , Quinazolinonas/química , Quinazolinonas/síntesis química , Aminas/química , Técnicas de Química Sintética , Cetonas/química , Modelos Moleculares , Oxazinas/químicaRESUMEN
This work describes a plant-mediated approach to the preparation of metal nanoparticles using leaf extract of Artemisia annua (A. annua), an ethno-medicinal plant widely found in Asia, which was used as reducing and stabilizing agent. A. annua is used in traditional Chinese medicine to alleviate fever. Au and Ag nanoparticles were prepared using a one-step aqueous method at room temperature without any toxic chemicals. The formation of Au and Ag nanoparticles was monitored by UV-vis spectroscopy. Synthesized nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), Fourier transform infrared (FT-IR) spectroscopy, and thermogravimetric analysis (TGA). TEM analysis of Au nanoparticles showed that they had triangular and spherical shapes with sizes ranging from 15 to 40 nm. The silver nanoparticles were predominantly spherical and uniformly sized (30-50 nm). The Au and Ag nanoparticles produced showed significant tyrosinase inhibitory and antibacterial effects. These results suggest that the synthesized nanoparticles provide good alternatives in varied medical and industrial applications.