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Owing to their great promise of high energy density, the development of safer lithium metal batteries (LMBs) has become the necessity of the hour. Herein, a scalable method based on conventional Celgard membrane (CM) separator modification is adopted to develop high-rate (10 mA cm-2 ) dendrite-free LMBs of extended cyclability (>1000 hours, >1500 cycles with 3 mA cm-2 , the bare fails within 50 cycles) with low over potential losses. The CM modification method entails the deposition of thin coatings of (≈6.6 µm) graphitic fluorocarbon (FG) via a large area electrophoretic deposition, where it helps for the formation of a stable LiF and carbon rich solid electrolyte interface (SEI) aiding a uniform lithium deposition even in higher fluxes. The FG@CM delivers a high transport number for Li ion (0.74) in comparison to the bare CM (0.31), indicating a facile Li ion transport through the membrane. A mechanistic insight into the role of artificial SEI formation with such membrane modification is provided here with a series of electrochemical as well as spectroscopic in situ/ex situ and postmortem analyses. The simplicity and scalability of the technique make this approach unique among other reported ones towards the advancement of safer LMBs of high energy and power density.
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Metal phosphorus trichalcogenide (MPX3) materials have aroused substantial curiosity in the evolution of electrochemical storage devices due to their environment-friendliness and advantageous X-P synergic effects. The interesting intercalation properties generated due to the presence of wide van der Waals gaps along with high theoretical specific capacity pose MPX3 as a potential host electrode in lithium batteries. Herein, we synthesized two-dimensional iron thio-phosphate (FePS3) nanoflakes via a salt-template synthesis method, using low-temperature time synthesis conditions in single step. The electrochemical application of FePS3 has been explored through the construction of a high-capacity lithium primary battery (LPB) coin cell with FePS3 nanoflakes as the cathode. The galvanostatic discharge studies on the assembled LPB exhibit a high specific capacity of ~1791 mAh g-1 and high energy density of ~2500 Wh Kg-1 along with a power density of ~5226 W Kg-1, some of the highest reported values, indicating FePS3's potential in low-cost primary batteries. A mechanistic insight into the observed three-staged discharge mechanism of the FePS3-based primary cell resulting in the high capacity is provided, and the findings are supported via post-mortem analyses at the electrode scale, using both electrochemical- as well as photoelectron spectroscopy-based studies.
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New ways of directly using solar energy to charge electrochemical energy storage devices such as batteries would lead to exciting developments in energy technologies. Here, a two-electrode photo rechargeable Li-ion battery is demonstrated using nanorod of type II semiconductor heterostructures with in-plane domains of crystalline MoS2 and amorphous MoOx . The staggered energy band alignment of MoS2 and MoOx limits the electron holes recombination and causes holes to be retained in the Li intercalated MoS2 electrode. The holes generated in the MoS2 pushes the intercalated Li-ions and hence charge the battery. Low band gap, high efficiency photo-conversion and efficient electron-hole separation help the battery to fully charge within a few hours using solar light. The proposed concept and materials can enable next generation stable photo-rechargeable battery electrodes, in contrast to the reported materials.
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Alkali and alkaline earth metal-ion batteries are currently among the most efficient electrochemical energy storage devices. However, their stability and safety performance are greatly limited when used with volatile organic liquid electrolytes. A solid state polymer electrolyte is a prospective solution even though poor ionic conductivity at room temperature remains a bottleneck. Here we propose the mixing of two similar polymer matrices, poly(dimethyl siloxane) and poly(ethylene oxide), to address this challenge. The resulting electrolyte matrix is denser and significantly improves room-temperature ionic conductivity. Ab initio analyses of the reaction between the cations and the polymers show that oxygen sites act as entrapment sites for the cations and that ionic conduction likely occurs through hopping between adjacent oxygen sites. Molecular dynamics simulations of the dynamics of both polymers and the dynamics of the polymer mix show that the more frequent and more pronounced molecular vibrations of the polymer mix are likely responsible for reducing the time between two consecutive oxygen entrapments, thereby speeding up the conduction process. This hypothesis is experimentally validated by the practically useful ionic conductivity (σ≈ 10-4 S cm-1 at 25 °C) and the improved safety parameters exhibited by a transparent flexible multi-cation (Li+, Na+ and Mg2+) conducting solid channel made up of the above mixed polymer system.
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Awareness of the consumer has increased the demand of safe and chemical-free foods, and consequently it has increased the demand of antibacterial bioactive compounds. In the present study, antibacterial compound produced by a local bacterial isolate NSD MTCC 10072, showing antagonistic activity against six human pathogens, was isolated, partially purified and characterized. Maximum production of antibacterial compound was observed between 51 and 60 h after seeding. The antibacterial activity of the compound was found to be thermostable up to 80 °C for 60 min and its efficacy was very good between pH 4 and 12. Minimum inhibitory concentration (25.84 µg/µl) of the antibacterial compound was observed against Streptococcus aureus NICM 2901. GC-MS analysis of the bacterium secreted chemical compound (C11H18N2O2) was used to identify the antimicrobial compound as Pyrrolo(1,2-a) pyrazine-1,4-dione, hexahydro-3-(2-methylpropyl). In Silico studies showed that the antimicrobial compound is non-toxic, non-irritating and followed Lipinski-type properties which suggested that the compound could be used as potential drug against different human pathogens.
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Antibacterianos/farmacologia , Bacillus cereus/metabolismo , Proteínas de Bactérias/farmacologia , Agentes de Controle Biológico/farmacologia , Antibacterianos/metabolismo , Bacillus cereus/isolamento & purificação , Bacillus subtilis/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Agentes de Controle Biológico/metabolismo , Escherichia coli/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium/efeitos dos fármacos , Pirróis/química , Pirróis/farmacologia , Staphylococcus aureus/efeitos dos fármacosRESUMO
A novel vertical non-van der Waals (non-vdW) heterostructure of graphene and hexagonal boron nitride (G/hBN) is realized and its application in direct four-electron oxygen reduction reaction (ORR) in alkaline medium is established. The G/hBN differs from previously demonstrated vdW heterostructures, where it has a chemical bridging between graphene and hBN allowing a direct charge transfer - resulting in high ORR activity. The ORR efficacy of G/hBN is compared with that of graphene-hBN vdW structure and individual layers of graphene and hBN along with that of benchmark platinum/carbon (Pt/C). The ORR activity of G/hBN is found to be on par with Pt/C in terms of current density but with much higher electrochemical stability and methanol tolerance. The onset potential of the G/hBN is found to be improved from 780 mV at a glassy carbon electrode to 930 mV and 940 mV in gold and platinum electrodes, respectively, indicating its substrate-dependent catalytic activity. This opens possibilities of new benchmark catalysts of metals capped with G/hBN atomic layers, where the underneath metal is protected while keeping the activity similar to that of pristine metal. Density functional theory-based calculations are found to be supporting the observed augmented ORR performance of G/hBN.
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Expression of a multitude of virulence factors by multi-drug resistant microbial strains, e.g., Carbapenem Resistant Escherichia coli (Family: Enterobacteriaceae; Class: Gammaproteobacteria), is responsible for resistance against beta-lactam antibiotics. Hemolysin production and induction of hemagglutination by bacterial surface receptors inflicts direct cytotoxicity by destroying host phagocytic and epithelial cells. We have previously reported that Berberis aristata, Camellia sinensis, Cyperus rotundus Holarrhena antidysenterica and Andrographis paniculata are promising herbal leads for targeting Carbapenem resistant Escherichia coli. These herbal leads were analyzed for their anti-hemolytic potential by employing spectrophotometric assay of hemoglobin liberation. Anti-hemagglutination potential of the extracts was assessed by employing qualitative assay of visible RBC aggregate formation. Camellia sinensis (PTRC-31911-A) exhibited anti-hemolytic potential of 73.97 ± 0.03%, followed by Holarrhena antidysenterica (PTRC-8111-A) i.e., 68.32 ± 0.05%, Berberis aristata (PTRC-2111-A) i.e., 60.26 ± 0.05% and Cyperus rotundus (PTRC-31811-A) i.e., 53.76 ± 0.03%. Comprehensive, visual analysis of hemagglutination inhibition revealed that only Berberis aristata (PTRC-2111-A) and Camellia sinensis (PTRC-31911-A) exhibited anti-hemagglutination activity. However, Andrographis paniculata (PTRC-11611-A) exhibited none of the inhibitory activities. Furthermore, the pair wise correlation analysis of the tested activities with quantitative phytochemical descriptors revealed that an increased content of alkaloid; flavonoids; polyphenols, and decreased content of saponins supported both the activities. Additionally, flow cytometry revealed that cell membrane structures of CRE were damaged by extracts of Berberis aristata (PTRC-2111-A) and Camellia sinensis (PTRC-31911-A) at their respective Minimum Inhibitory Concentrations, thereby confirming noteworthy antibacterial potential of both these extracts targeting bacterial membrane; hemolysin and bacterial hemagglutination.
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Antibacterianos/farmacologia , Membrana Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Extratos Vegetais/farmacologia , Resistência beta-Lactâmica , Animais , Antibacterianos/isolamento & purificação , Carbapenêmicos/farmacologia , Eritrócitos/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Escherichia coli/patogenicidade , Citometria de Fluxo , Hemaglutinação/efeitos dos fármacos , Hemoglobinas/análise , Hemólise/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/isolamento & purificação , Ratos , Espectrofotometria , Virulência/efeitos dos fármacosRESUMO
The multi-drug resistance offered by Carbapenem Resistant Escherichia coli (Family: Enterobacteriaceae; Class: Gammaproteobacteria) against third line antibiotics can be attributed towards its ability to develop biofilm. Such process involves adhesion and quorum-sensing induced colonization leading to biomass development. The present study explored the anti-adhesion, anti-quorum sensing and anti-biofilm potential of 05 pre-standardized potent herbals. Berberis aristata (PTRC-2111-A) exhibited maximum potential in all these activities i.e. 91.3% ± 0.05% (Anti-adhesion), 96.06% ± 0.05% (Anti-Quorum sensing) and 51.3% ± 0.07% (Anti-Biofilm formation) respectively. Camellia sinensis (PTRC-31911-A) showed both anti-adhesion (84.1% ± 0.03%) and anti-quorum sensing (90.0%) potential while Holarrhena antidysenterica (PTRC-8111-A) showed only anti-quorum sensing potential as compared to standards/antibiotics. These findings were in line with the molecular docking analysis of phytoligands against Lux S and Pilin receptors. Furthermore, the pairwise correlation analysis of the tested activities with qualitative, quantitative and bioactivity functional descriptors revealed that an increased content of alkaloid, moderate content of flavonoids and decreased content of tannins supported all the three activities. In addition, nitric oxide and superoxide scavenging activity were found to be correlated with anti-quorum sensing activity. The findings indicated clearly that B. aristata (Family: Berberidaceae) and C. sinensis (Family: Theaceae) were potent herbal leads with significant therapeutic potential which further needs to be explored at pre-clinical level in the future.
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Biofilmes/efeitos dos fármacos , Produtos Biológicos/farmacologia , Carbapenêmicos/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/fisiologia , Extratos Vegetais/farmacologia , Percepção de Quorum/efeitos dos fármacos , Resistência beta-Lactâmica , Alcaloides/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Produtos Biológicos/química , Flavonoides/química , Masculino , Testes de Sensibilidade Microbiana , Modelos Biológicos , Modelos Moleculares , Conformação Molecular , Simulação de Acoplamento Molecular , Fenóis/química , Extratos Vegetais/química , RatosRESUMO
Increasing occurrence of gastroenteritis outbreaks caused by food borne opportunistic microorganisms has become a major problem in food industry as well as in immunocompromised host. Antimicrobial agents are losing their efficacy due to increase in the microbial resistance. For such reasons, conventional treatment has become limited to manage the infections state. Need of the hour is to instigate the search for safer holistic alternatives. The present study was hence conducted to assess the antibiofilm effect and mode of action of aquo alcoholic extracts of Holarrhena antidysentrica (Ha) and Andrographis paniculata (Ap) against the Salmonella enterica serovar typhimurium. Both the extracts were screened for the presence of phytocompounds followed by the characterization using Attenuated Total Reflection (ATR) infrared spectroscopy and bioactivity finger print analysis. Anti-biofilm assays were determined to test the potential of both extracts to inhibit the biofilm formation, while Propidium Iodide (PI) uptake analysis revealed that cell membrane was damaged by the exposure of nutraceuticals for 1 h. This study has demonstrated that both nutraceuticals have anti-biofilm and antimicrobial activity perturbing the membrane integrity of food-borne S. typhimurium and could be used as curative remedy to control the food borne microbial infection.
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Andrographis/química , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Holarrhena/química , Extratos Vegetais/farmacologia , Salmonella typhimurium/efeitos dos fármacos , Antibacterianos/isolamento & purificação , Biofilmes/crescimento & desenvolvimento , Membrana Celular/fisiologia , Permeabilidade/efeitos dos fármacos , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/isolamento & purificação , Propídio/análise , Salmonella typhimurium/fisiologia , Análise Espectral , Coloração e RotulagemRESUMO
Aquo-ethanolic extract of Camellia sinensis (PTRC-31911-A), standardized using Fourier transform infrared analysis, was found to have seven common functional groups in comparison with pre-identified marker compound 'quercetin'. Phyto-chemical quantitation analysis revealed the presence of 10.65 µg/mg of flavonoids. The bioactivity fingerprint profile of PTRC-31911-A includes IC50 (Hydroxyl radical site specific scavenging) = 11.36 ± 0.5 µg/mL, IC80 (Hydroxyl radical non-site specific scavenging) = 26.44 ± 0.5 µg/mL and IC50 (Superoxide ion scavenging) = 10.141 ± 0.5 µg/mL. The drug combination analysis of PTRC-31911-A with five third-line antibiotics was carried out against carbapenem-resistant Escherichia coli. The analysis of combination of PTRC-31911-A (6.25-1000 µg/mL) and antibiotics (6.25-1000 µg/mL) revealed synergistic behaviour (fractional inhibitory concentration indices < 1) with tigecycline, ertapenem, meropenem, colistin and augmentin. The lead combination of PTRC-31911-A + ertapenem or meropenem showed maximum augmentative potential at 50 and 100 µg/mL, respectively, with nearly five-fold decrease in minimum inhibitory concentrations as compared with respective antibiotics alone. The synergistic effects implied that the antibacterial combinations of PTRC-31911-A and ertapenem, meropenem, colistin, tigecycline or augmentin would be more effective than a single monotherapy with either of the antibacterial agent.
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Camellia sinensis/química , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Flavonoides/farmacologia , Extratos Vegetais/farmacologia , Combinação Amoxicilina e Clavulanato de Potássio/farmacologia , Colistina/farmacologia , Ertapenem , Sequestradores de Radicais Livres/farmacologia , Meropeném , Testes de Sensibilidade Microbiana , Minociclina/análogos & derivados , Minociclina/farmacologia , Compostos Fitoquímicos/farmacologia , Folhas de Planta/química , Tienamicinas/farmacologia , Tigeciclina , beta-Lactamas/farmacologiaRESUMO
Nonaqueous rechargeable Li-O2 batteries are recognized as possible alternatives to the currently established Li-ion battery technology for next-generation traction by virtue of their high specific energy. However, the technology is still far from commercial realization mainly due to the performance-limiting reactions at the cathode. The insulating discharge product, Li2O2, can passivate the cathode leading to issues such as low specific capacity and early cell death. Herein, the -OH functionalities at the cathode, incorporated by polysaccharide addition, are shown to enhance the discharge capacity and cyclability. The -OH functional group (high pKa) at the cathode helps to stabilize the intermediate, LiO2, via an energetically favorable pathway and delays the precipitation to Li2O2, without any parasitic reaction, unlike the other reported low pKa additives. The role of the functionalities is studied using various experimental techniques and first principles density functional theory based studies. This approach provides a rational design route for the cathodes that provide high capacities for the emergent Li-O2 batteries.
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Tweaking the electrolyte of the anode compartment of zinc-air battery (ZAB) system is shown to be extending the charge-discharge cyclability of the cell. An alkaline zinc (Zn)-air cell working for â¼32 h (192 cycles) without failure is extended to >55 h (>330 cycles) by modifying the anode compartment with a mixture electrolyte of KOH and LiOH. The cell containing the mixture electrolyte has a low overpotential for charging along with high discharge capacity. The role of Li+ ions in tuning the electrode morphology and electrodics is studied both theoretically and experimentally. The synergistic effect of Li+ and K+ ions in the electrolyte on improved ZAB performance is proven. This study can pave new ways for the commercial implementation of ZAB, where it has already proven its potential in low-cost, high energy density, and mobility applications.
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Drug resistance among microbial pathogens and oxidative stress caused by reactive oxygen species are two of the most challenging global issues. Firstly, drug-resistant pathogens cause several fatalities every year. Secondly aging and a variety of diseases, such as cardiovascular disease and cancer, are associated with free radical generated oxidative stress. The treatments currently available are limited, ineffective, or less efficient, so there is an immediate need to tackle these issues by looking for new therapies to resolve resistance and neutralize the harmful effects of free radicals. In the 21st century, the best way to save humans from them could be by using plants as well as their bioactive constituents. In this specific context, Jasminum is a major plant genus that is used in the Ayurvedic system of medicine to treat a variety of ailments. The information in this review was gathered from a variety of sources, including books, websites, and databases such as Science Direct, PubMed, and Google Scholar. In this review, a total of 14 species of Jasminum have been found to be efficient and effective against a wide variety of microbial pathogens. In addition, 14 species were found to be active free radical scavengers. The review is also focused on the disorders related to oxidative stress, and it was concluded that Jasminum grandiflorum and J. sambac normalized various parameters that were elevated by free radical generation. Alkaloids, flavonoids (rutoside), terpenes, phenols, and iridoid glucosides are among the main phytoconstituents found in various Jasminum species. Furthermore, this review also provides insight into the mechanistic basis of drug resistance, the generation of free radicals, and the role of Jasminum plants in combating resistance and neutralizing free radicals.
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Convolvulus prostratus Forssk., a nootropic herb used in traditional medicinal systems, is also frequently known by its taxonomic synonym Convolvulus pluricaulis. In Indian medicinal system - Ayurveda - it is named as Shankhpushpi. According to the ancient literature, this herb has been attributed with several therapeutic properties, such as anxiolytic, neuroprotective, antioxidant, analgesic, immunomodulatory, antimicrobial, antidiabetic and cardioprotective activities. This medicinal herb has been reported to contain many bioactive phytoconstituents, such as, alkaloid (convolamine), flavonoid (kaempferol) and phenolics (scopoletin, ß-sitosterol and ceryl alcohol), that have been ascribed to the observed medicinal properties. Several research teams across the globe have highlighted the neuro-pharmacological profile of C. prostratus, wherein, the neuroprotective, nootropic and neuro-modulatory roles have been described. Besides, role of C. prostratus extracts in neurodegeneration has been well demonstrated. Despite of such elaborative preclinical pharmacological profile, detailed clinical investigations and mechanistic mode-of-action studies of this important herb are yet to be executed. The present review is attempted to showcase the phytochemical profile, pharmacological attributes and medicinal information of C. prostratus; with comprehensive research gap analysis. It is hoped that the scientific update on the ethnomedicinal aspects of this herb would thrive research propagation and development of the CNS phytopharmaceuticals, originated from C. prostratus.
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On-site peroxide generation via electrochemical reduction is gaining tremendous attention due to its importance in many fields, including water treatment technologies. Oxidized graphitic carbon-based materials have been recently proposed as an alternative to metal-based catalysts in the electrochemical oxygen reduction reaction (ORR), and in this work we unravel the role of C=O groups in graphene towards sustainable peroxide formation. We demonstrate a versatile single-step electrochemical exfoliation of graphite to graphene with a controllable degree of oxygen functionalities and thickness, leading to the formation of large quantities of functionalized graphene with tunable rate parameters, such as the rate constant and exchange current density. Higher oxygen-containing exfoliated graphene is known to undergo a two-electron reduction path in ORR having an efficiency of about 80 ± 2% even at high overpotential. Bulk production of H2O2 via electrolysis was also demonstrated at low potential (0.358 mV vs RHE), yielding ≈34 mg/L peroxide with highly functionalized (≈23 atom %) graphene and ≈16 g/L with low functionalized (≈13 atom %) graphene, which is on par with the peroxide production using state-of-the-art precious-metal-based catalysts. Hence this method opens a new scheme for the single-step large-scale production of functionalized carbon-based catalysts (yield ≈45% by weight) that have varying functionalities and can deliver peroxide via the electrochemical ORR process.
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Systemic lupus erythematosus (SLE) is a complex autoimmune disorder involving a dysregulated immune response which ultimately leads to multiple organ failure. Several immunological and cellular checkpoints are available as drug targets. However, the available chemosynthetic drugs such as non-steroidal anti-inflammatory drugs and corticosteroids provide limited therapy with extreme toxicities. Moreover, the disease heterogeneity in SLE is very difficult to manage by a single drug component. Hence, it is imperative to utilize the holistic capabilities of natural plant products as immunomodulators and intracellular signaling regulators, thereby providing an auxiliary option of treatment. Additionally, the herbal drugs also serve as symptomatic relief providers, thereby serving as a prophylactic remedy in case of cerebrovascular, hepatic, nephropathological, hematological, cardiopulmonary, mucocutaneous and musculoskeletal manifestations of SLE. The present review attempts to showcase the current state of knowledge regarding the utility of plant-derived phyto-metabolites with their probable mechanistic roles in treating SLE, by means of targeting the signaling cascade, proinflammatory cytokine production and B-T cell co-stimulation. It is hoped that further preclinical and clinical studies will be embarked upon in order to understand the underlying therapeutic and mechanistic aspects of these medicinal herbs.
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Produtos Biológicos/uso terapêutico , Avaliação Pré-Clínica de Medicamentos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Metaboloma , Plantas/metabolismo , Animais , Humanos , Lúpus Eritematoso Sistêmico/etiologia , Lúpus Eritematoso Sistêmico/fisiopatologia , FitoterapiaRESUMO
Polymer based solid electrolytes (SEs) are envisaged as futuristic components of safer solid state energy devices. But the semi-crystalline nature and slow dynamics of the host polymer matrix are found to hamper the ion transport through the solid polymer network and hence solid state devices are still far beyond the scope of practical application. In this study, we unravel the synergistic roles of Li salt (LiClO4) and two different polymers - polyethylene oxide (PEO) and polydimethyl siloxane (PDMS), in the Li ion transport through their solid blend based electrolyte. A detailed study using dielectric spectroscopy and thermo-mechanical analysis is conducted to understand the tunability of the PEO chain dynamics with LiClO4 and the mechanism of hopping of Li ions by forming ion pairs with oxygen dipoles on the PEO backbone is established. Despite the lack of PDMS's capability to solvate ions and promote ion transport directly, its proper mixing within the PEO host matrix is demonstrated to enhance ion transport due to the influence of PDMS on the segmental dynamics of PEO. A detailed molecular dynamics study supported by experimental validation suggests that even inert polymers can affect the dynamics of the active host matrix and increase ion transport, leading to next generation high ionic conductivity solid matrices, and opens new avenues in designing polymer based transparent electrolytes.
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OBJECTIVES: Berberis aristata is known to contain a variety of phenolic compounds contributing to its holistic capability of mitigating bacterial multidrug resistance. METHODS: B. aristata stem bark extract was prepared and was characterised using liquid chromatography-mass spectrometry (LC-MS). The antimicrobial efficacy of the extract against carbapenem-resistant Escherichia coli was assessed in vivo in an animal model using Sprague Dawley rats. Microbial counts in blood and urine, physical health status, haematological and biochemical analysis of blood, and histopathology of the kidney were assessed as the study endpoints. RESULTS: An aquo-alcoholic extract of B. aristata (PTRC-2111-A) was found to effectively manage peritonitis induced by carbapenem-resistant E. coli in a rat model at a single post-exposure prophylactic dose of 0.5mg/kg body weight (BW). The extract was also found to show a no observed adverse effect level (NOAEL) up to a dose of 2000mg/kg BW. Physical, immunological, haematological, biochemical and histopathological aberrations were found to be restored to normal in the herbal-treated group at a dose of 0.5mg/kg BW. CONCLUSIONS: The antimicrobial and hepatorenal protective ability of PTRC-2111-A could be attributed to the presence of isoquinoline alkaloids.
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Antibacterianos/administração & dosagem , Berberis/química , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Infecções por Escherichia coli/tratamento farmacológico , Escherichia coli/efeitos dos fármacos , Peritonite/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Animais , Antibacterianos/isolamento & purificação , Sangue/microbiologia , Análise Química do Sangue , Cromatografia Líquida , Modelos Animais de Doenças , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/patologia , Isoquinolinas/administração & dosagem , Isoquinolinas/isolamento & purificação , Rim/patologia , Masculino , Espectrometria de Massas , Peritonite/microbiologia , Peritonite/patologia , Extratos Vegetais/isolamento & purificação , Ratos Sprague-Dawley , Resultado do Tratamento , Urina/microbiologiaRESUMO
BACKGROUND: Rheumatoid arthritis (RA), an autoimmune inflammatory disorder with synovial hyperplasia, destruction of cartilage, bone damage is often associated with risk of infections. Such risk could be attributed towards usage of immunosuppressive agents. Thus, the present study was undertaken to evaluate the anti-arthritic efficacy of aquo-alcoholic extract of Camellia sinensis (L.). MATERIAL AND METHODS: Dried leaves of Camellia sinensis (L.) or Cs were filtered and extracted in 1:1 aqueous: ethanol by Soxhlet apparatus followed by lyophilization and spray drying to develop amorphous powder. Four different oral doses (50, 100, 200, 400mg/kg/body wt.) of aquo-alcoholic extract were evaluated for anti-edematogenic effect in collagen induced arthritis model. The selected anti-arthritic doses of Cs were evaluated for the oxidative stress markers like Glutathione [5-5'dithio-bis-2-nitrobenzoicacid (DTNB)], Superoxide dismutase [Epinephrine], Catalase [Hydrogen peroxide], Lipid peroxidation [Thiobarbituric acid reactive substance (TBARS)], Nitric oxide [Griess reagents:Nitrobluetetrazolium], Articular elastase [N-methoxysuccinyl-Ala-Ala-Pro- Val p-nitroanilide] in joints followed by haematological evaluation including RBC, WBC, Haemoglobin, platelets and haematocrit. To validate these biochemical changes, the radiological and histopathological (Haematoxylin & Eosin) evaluation was also conducted. RESULTS: The selected anti-arthritic dose of Cs i.e. 400mg/kg/body wt. (â¼60% anti-arthritic efficacy on 35th day) could be attributed towards significant (p<0.05) increase in the levels of enzymatic (Superoxide dismutase and Catalase) and non-enzymatic (Glutathione) antioxidants by 34%, 59% and 50% respectively. Simultaneously, the significant (p<0.05) reduction of lipid peroxides, nitrite radical and elastase activity by 32%, 45% & 32% respectively as compare to control indicated overall decrease in oxidative stress. Haematological evaluation revealed restoration of RBC, WBC and platelets level in treatment group. The confirmatory analysis utilizing radiological and histological assessment showed alleviation of joint deformity, tissue swelling, pannus formation and neutrophils infiltration in treatment group as compared to collagen induced arthritis. CONCLUSION: The analysis showed that Cs can play an effective role in reduction of oxidative stress by modulating levels of antioxidants, reducing levels of free radicals while restoring normal haematopoietic cascade as observed in collagen induced arthritis model. Thus, the cumulative dose impact of 400mg/kg body wt., over a period of 14days also found extremely effective in terms of safeguarding their structural conformity against such auto-immune disorder.