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1.
Chemosphere ; 351: 141272, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38262491

ABSTRACT

Herein, a coordination polymer gel is proposed for the determination of As(III) in real samples through multispectroscopic techniques viz. spectrophotometry, spectrofluorimetry, and inductively coupled plasma atomic emission spectroscopy (ICP-AES). Taguchi L32 (46 21) design and adaptive neuro fuzzy inference system (ANFIS) optimized the controllable factors affecting the extraction yielding an experimental S/N ratio of 39.94 dB. The fluorescence quenching (KSV = 2.63 × 106 L mol-1) was static with photoelectron transfer being the main mechanism confirmed by the density functional theory calculations. The limits of detection (LODs), limits of quantification (LOQs) and linear ranges were 0.038 µg L-1, 0.13 µg L-1 and 1.67-116.67 µg L-1, 0.40 µg L-1, 1.21 µg L-1 and 1.67-33.33 µg L-1, 1.07 µg L-1, 3.24 µg L-1 and 3.32-35.37 µg L-1 for the developed enrichment coupled ICP-AES, spectrophotometry and fluorescence sensing methods. Among these methods, the enrichment - ICP-AES method has the lowest LOD, LOQ and the widest linear range followed by the enrichment - spectrophotometry and fluorescene sensing methods. Spectrofluorimetry offers high sensitivity, selectivity, and possible real time monitoring, spectrophotometry provides a cost-effective and versatile option, while ICP-AES manifests multi-element analysis with high sensitivity and low interference. The developed methods were validated and employed for the successful determination of trace As(III) in real samples. The employment of these methods enhances the overall analytical capability for a wide range of sample types and concentrations.


Subject(s)
Trace Elements , Spectrophotometry, Atomic/methods , Trace Elements/analysis , Water , Spectrometry, Fluorescence , Limit of Detection
2.
J Hazard Mater ; 457: 131783, 2023 Sep 05.
Article in English | MEDLINE | ID: mdl-37327609

ABSTRACT

A novel coordination polymer gel based on zirconium(IV) and 2-thiobarbituric (ZrTBA) was synthesized and explored its potential to remediate As(III) from water. Box-Behnken design with desirability function and genetic algorithm yielded the optimized conditions (initial concentration=194 mg L-1, dosage = 42.2 mg, time= 95 min and pH = 4.9) for maximum removal efficiency (99.19 %). The experimental saturation capacity for As(III) was 178.30 mg g-1. The steric parameter n > 1 of the best fitted statistical physics model: monolayer with two energies (R2 = 0.987-0.992) suggested multimolecular mechanism with vertical orientation of As(III) molecules onto the two active sites. XPS and FTIR confirmed the two active sites being zirconium and oxygen. The adsorption energies (E1 = 35.81-37.63 kJ/mol; E2 = 29.50-36.49 kJ/mol) and isosteric heat of adsorption indicated that physical forces governed the As(III) uptake. DFT calculations implied that the weak electrostatic interaction and hydrogen bonding were involved. The best fitted (R2>0.99) fractal like pseudo first order model established energetic heterogeneity. ZrTBA showed excellent removal efficiency in the presence of potential interfering ions and could be used up to 5 cycles of adsorption-desorption with < 8 % loss in the efficiency. ZrTBA removed ≥96.06 % As(III) from real water samples spiked at different levels of As(III).

3.
Rev Sci Instrum ; 93(11): 113311, 2022 Nov 01.
Article in English | MEDLINE | ID: mdl-36461536

ABSTRACT

The absolute response of a real-time proton detector, composed of a microchannel plate (MCP) assembly, an imaging lens, and a charge-coupled device (CCD) camera, is calibrated for the spectral characterization of laser-accelerated protons, using a Thomson parabola spectrometer (TPS). A slotted CR-39 plate was used as an absolute particle-counting detector in the TPS, simultaneously with the MCP-CCD detector to obtain a calibration factor (count/proton). In order to obtain the calibration factor as a function of proton energy for a wide range of proton numbers, the absolute response was investigated for different operation parameters of the MCP-CCD detector, such as MCP voltage, phosphor voltage, and CCD gain. A theoretical calculation for the net response of the MCP was in good agreement with the calibrated response of the MCP-CCD detector, and allows us to extend the response to higher proton energies. The response varies in two orders of magnitude, showing an exponential increase with the MCP voltage and almost linear increase with the phosphor voltage and the CCD gain. The calibrated detector enabled characterization of a proton energy spectrum in a wide dynamic range of proton numbers. Moreover, two MCP assemblies having different structures of MCP, phosphor screen, and optical output window have been calibrated, and the difference in the absolute response was highlighted. The highly-sensitive detector operated with maximum values of the parameters enables measuring a single proton particle and evaluating an absolute spectrum at high proton energies in a single laser shot. The absolute calibrations can be applied for the spectral measurement of protons using different operating voltages and gains for optimized response in a large range of proton energy and number.

4.
Ann Oper Res ; : 1-24, 2022 Sep 05.
Article in English | MEDLINE | ID: mdl-36091932

ABSTRACT

The thought to put forward a queuing model proposed in this work was its pertinence in everyday life wherever we can see the uses of computing and networking systems. Industrial software developers and system managers can consider the results of the model to evolve their system for better results. Here we present a novel queueing model having erratic server with delayed repair and balking. Two distinct breakdowns i.e. active and passive breakdown for the system are also considered with their respective amendments. This model is closely related with the smooth functioning of the system during some internal faults (virus attack, electricity failures etc.). The performance indicators which are utilized in enhancing the service standards are obtained using supplementary variable technique. Using ANFIS soft computing technique we have compared the analytical results with those of neuro fuzzy results. Furthermore single and bi-objective minimization problems are considered and minima is obtained using particle swarm optimization and multi objective genetic algorithm respectively. Also, the minimization problems are shown as a convex programming problem to ensure the global optimality of the result. The proposed approach makes it conceivable to accomplish a relevant harmony between operational expenses and administration quality.

5.
Plants (Basel) ; 11(5)2022 Feb 28.
Article in English | MEDLINE | ID: mdl-35270123

ABSTRACT

Jasmonates (JAs) are lipid-derived compounds that function in plants as key signaling compounds during stressful conditions. This study aimed to examine the effects of exogenous fo-liar-JA application (100 µmol L-1) on the morpho-physiological response of two soybean varieties (parachinar-local and swat-84) grown under different NaCl regimes (0, 40, 80, and 120 mM). Results show that exogenous JA application alone and in combination with salt stress altered the growth and metabolism of both soybeans. For instance, they accumulated significant amounts of Na+ and Cl-, while their K+, Mg2+, Fe2+, Mn2+, B3+, and P3+ contents were low. Further, photosynthetic pigments Chl a and Chl b increased at low concentrations of salt and exogenous JA. Car decreased under both salt and exogenous JA as compared with untreated control. In addition, sugar, phenol, and protein content increased under both salt and exogenous JA application. In contrast, the exogenous JA application alleviated the negative impact of salt stress on the growth and metabolism of both soybeans. Further, the high concentrations of soluble protein and phenol in the leaves of both soybeans may contribute to their ability to adapt to salinity. However, molecular studies are necessary to understand the ameliorative role of exogenous JA in the growth and metabolism of salt-treated young seedlings in both soybean varieties.

6.
Rev Sci Instrum ; 92(2): 023302, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-33648087

ABSTRACT

We present a proof of principle for onsite calibration of a radiochromic film (EBT3) using CR-39 as an absolute proton-counting detector and laser-accelerated protons as a calibration source. A special detector assembly composed of aluminum range filters, an EBT3 film, and a CR-39 detector is used to expose the EBT3 film with protons in an energy range of 3.65 MeV-5.85 MeV. In our design, the proton beam is divided into small beamlets and their projection images are taken on the EBT3 film and the CR-39 detector by maintaining a certain distance between the two detectors. Owing to the geometrical factor of the configuration and scattering inside the EBT3, the areal number density of protons was kept below the saturation level of the CR-39 detector. We also present a method to relate the number of protons detected on the CR-39 in a narrow energy range to protons with a broad energy spectrum that contribute to the dose deposited in the EBT3 film. The energy spectrum of protons emitted along the target normal direction is simultaneously measured using another CR-39 detector installed in a Thomson parabola spectrometer. The calibration curves for the EBT3 film were obtained in the optical density range of 0.01-0.25 for low dose values of 0.1 Gy-3.0 Gy. Our results are in good agreement with the calibrations of the EBT3 film that are traditionally carried out using conventional accelerators. The method presented here can be further extended for onsite calibration of radiochromic films of other types and for a higher range of dose values.

7.
Drug Metab Pers Ther ; 36(3): 247-250, 2021 03 29.
Article in English | MEDLINE | ID: mdl-33770821

ABSTRACT

OBJECTIVES: Pain in joints is a major clinical problem since ancient times. Waja-uz-Zahr stands for low back pain which may arise from internal or external structures of lumbosacral region due to Su-e-Mizaj sada or maddi due to the surplus of Burudat or accumulation of Kham Balgham in lower back. Imala (diversion) and Taqiya-e-Mavad (Evacuation) are inevitable in case of maddi amraz. Hijama (cupping therapy) is a simple, safe, tolerable, and effective regimenal modality, helpful in the treatment of aches and pains. Gruner mentioned a special kind of cupping method in the canon of medicine of Avicenna where cupping glasses are glided over a specified area of body intending the diversion of morbid material under the name of Bier's treatment. The purpose of present case series was to provide the insight into the effect of gliding cupping in low back ache. CASE PRESENTATION: Three patients of Waja-uz-Zahr, aged between 29 and 64 years, were given gliding cupping treatment after the application of Roghan-e-Surkh on lumbosacral region alternatively for 14 days. Oswestry disability index (ODI) and visual analogue scale (VAS) were used for the assessment of efficacy. Improvement, in case 1, case 2, and case 3 in ODI score was 42.42, 68.18, and 62.50%, respectively while in VAS score, it was 50, 62.5, and 50%, respectively, was observed without any adverse effect. CONCLUSIONS: On the basis of the above results, it can be concluded that the gliding cupping therapy may be used as an effective modality of treatment for low back ache.


Subject(s)
Low Back Pain , Adult , Humans , Low Back Pain/therapy , Middle Aged , Pain Measurement , Research Design
8.
Article in English | MEDLINE | ID: mdl-32727342

ABSTRACT

Nature has the potential to reduce metal salts to their relative nanoparticles. Traditionally, physical and chemical methods were used for the synthesis of nanoparticles but due to the use of toxic chemicals, non-ecofriendly methods and other harmful effects, green chemistry approaches are now employed for synthesizing nanoparticles which are basically the most cost effective, ecofriendly and non-hazardous methods. In this review, we aimed to evaluate and study the details of various mechanisms used for green synthesis of silver nanoparticles from plants, their size, shape and potential applications. A total of 150 articles comprising both research and review articles from 2009 to 2019 were selected and studied in detail to get in-depth knowledge about the synthesis of silver nanoparticles specifically through green chemistry approaches. Silver ions and their salts are well known for their antimicrobial properties and have been used in various medical and non-medical applications since the emergence of human civilization. Miscellaneous attempts have been made to synthesize nanoparticles using plants and such nanoparticles are more efficient and beneficial in terms of their antibacterial, antifungal, antioxidant, anti-biofilm and cytotoxic activities than nanoparticles synthesized through physical and chemical processes. Silver nanoparticles have been studied as an important research area due to their specific and tunable properties and their application in the field of biomedicine such as tissue and tumor imaging and drug delivery. These nanoparticles can be further investigated to find out their antimicrobial potential in cell lines and animal models.


Subject(s)
Green Chemistry Technology/methods , Metal Nanoparticles/chemistry , Plant Extracts/chemical synthesis , Plant Structures/chemistry , Silver/chemistry , Animals , Anti-Bacterial Agents/chemical synthesis , Antioxidants/chemical synthesis , Green Chemistry Technology/trends , Humans , Plant Extracts/isolation & purification
9.
Food Chem ; 334: 127563, 2021 Jan 01.
Article in English | MEDLINE | ID: mdl-32791433

ABSTRACT

A new magnetic Cu(II) IIP (Fe3O4@IIP-IDC) is synthesized by polymerization of Imidazole-4,5-dicarboxylic acid functionalized Allyl chloride, and significant improvement of its performance has been compared. SPE parameters were optimized using Box-Behnken design to achieve the twin objectives of quantitative determination and removal of Cu(II). FLPSO kinetic model and BS isotherm model fits well with the capacity of 175 mg g-1. Analytical figures of merit includes a linearity range of 10-5,000 µg L-1 (R2 = 0.9986), preconcentration factor of 50 after eluting with 5 mL of 1 M HNO3, LOD of 1.03 µg L-1 and LOQ of 4.5 µg L-1. Accuracy was assessed by analysis of SRM (Standard Reference Material) and recovery experiments after spiking in food samples (Tea, coffee, chocolate, spinach, infant milk substitute) and battery wastewater. Ease of use, reusability (15 cycles), rapid adsorption and high selectivity makes it a promising candidate for efficient and selective removal and trace determination.


Subject(s)
Copper/analysis , Food Analysis/methods , Molecular Imprinting/methods , Polymers/chemistry , Water Pollutants, Chemical/analysis , Adsorption , Allyl Compounds/chemistry , Copper/isolation & purification , Dicarboxylic Acids/chemistry , Food Analysis/instrumentation , Food Contamination/analysis , Imidazoles/chemistry , Limit of Detection , Magnetic Phenomena , Wastewater/analysis , Water Pollutants, Chemical/isolation & purification
10.
Gastroenterol Res Pract ; 2020: 4253174, 2020.
Article in English | MEDLINE | ID: mdl-33204254

ABSTRACT

Combretum fragrans (Combretaceae) is a Cameroonian medicinal plant containing various secondary metabolites and traditionally used for the treatment of several pathologies. Two cycloartane-type triterpenes, Combretin A and Combretin B, were isolated from this plant. This study was aimed at evaluating the anti-inflammatory, antioxidant, and anticolitis effects of these compounds. In vitro anti-inflammatory properties were evaluated by inhibition of cyclooxygenase, 5-lipoxygenase, and denaturation of the protein; antioxidant properties were assessed by using 1,1-diphenyl-2-picrylhydrazyl (DPPH), (2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid)) ABTS•+, capacity tests ferric reducing antioxidant (FRAP), and trapping nitric oxide. For in vivo analysis, we used the model of ulcerative colitis induced by Dextran Sulfate Sodium (DSS). Studies of the anti-inflammatory activity showed that Combretin A and Combretin B had maximal inhibitory activity on cyclooxygenase (71.92% and 89.59%), 5-lipoxygenase (76.68% and 91.21%), and protein denaturation (63.93% and 87.78%). Antioxidant activity on DPPH, ABTS•+, ferric reducing antioxidant capacity (FRAP), and nitric oxide scavenging showed that Combretin A and Combretin B showed good antioxidant activities. These compounds significantly reduced the signs of DSS-induced colitis in the treated animals by preventing the weight loss of the animals, by significantly reducing the disease activity index, improving the condition of the stool, preventing the reduction of the length of the colon, and preventing the degradation of the colon. This study revealed that Combretin A and Combretin B have anti-inflammatory, antioxidant, and curative properties against colitis experimentally induced by DSS in rats.

11.
Drug Metab Pers Ther ; 2020 Oct 05.
Article in English | MEDLINE | ID: mdl-33006948

ABSTRACT

Objectives Stroke is one of the leading causes of death and disability in India. The estimated adjusted prevalence rate of stroke range, 84-262/100,000 in rural and 334-424/100,000 in urban areas. A deficit in motor function affects mobility, daily activity of life. Rehabilitation is the most useful method to reduce deficit motor function. Hemiplegia (Falij), is one of the most common disability resulting from stroke has been described by Unani physicians, and they treat the disease effectively on the principle of Tanqia (evacuation) and Tadeel (alterative). Hence, a study contemplated to determine the effectiveness of Majoon Falasfa (MF) and Roghan-e-Surkh (RS) in post-stroke disability. Methods This trail was an open labeled, pre-post analysis, carried out at the National Institute of Unani Medicine (NIUM), on thirty (n=30) subjects of both genders, with post-stroke disability, and given MF 6 g orally with water in the morning and evening on empty stomach daily along with massage of 15 mL RS on the affected part once a day for 45 days with three follow up fortnightly (i.e. 15th, 30th, and 45th day). Patients were assessed on each follow up based on Barthel Index of Activities of Daily Living (ADL). Pre- and post-treatment values of the scale were analyzed statistically using Student's 't' test and paired Proportion test. Results The treatment difference as pre-post values determine with Barthel Index was found statistically highly significant (p<0.001). Safety parameters found within the normal range. Conclusions Finding of this trial recommended that both Unani formulations are effective in the management of post-stroke disability, and it can be used to decrease the dependency and boost the quality of life of the patients. No adverse effect was noted during the treatment of test formulations.

12.
Drug Des Devel Ther ; 14: 3777-3786, 2020.
Article in English | MEDLINE | ID: mdl-32982182

ABSTRACT

INTRODUCTION: Behavioral sensitization is a phenomenon that develops from intermittent exposure to nicotine and other psychostimulants, which often leads to heightened locomotor activity and then relapse. Sulfonamides that act as carbonic anhydrase inhibitors have a documented role in enhancing dopaminergic tone and normalizing neuroplasticity by stabilizing glutamate release. OBJECTIVE: The aim of the current study was to explore synthetic sulfonamides derivative 4-fluoro-N-(4-sulfamoylbenzyl) benzene-sulfonamide (4-FBS) (with documented carbonic anhydrase inhibitory activity) on acquisition and expression of nicotine-induced behavioral sensitization. METHODS: In the acquisition phase, selected 5 groups of mice were exposed to saline or nicotine 0.5mg/kg intraperitoneal (i.p) for 7 consecutive days. Selected 3 groups were administered with 4-FBS 20, 40, and 60 mg/kg p.o. along with nicotine. After 3 days of the drug-free period, ie, day 11, a challenge dose of nicotine was injected to all groups except saline and locomotor activity was recorded for 30 minutes. In the expression phase, mice were exposed to saline and nicotine only 0.5 mg/kg i.p for 7 consecutive days. After 3 days of the drug-free period, ie, day 11, 4-FBS at 20, 40, and 60 mg/kg were administered to the selected groups, one hour after drug a nicotine challenge dose was administered, and locomotion was recorded. At the end of behavioral experiments, all animals were decapitated and the striatum was excised and screened for changes in adenosine levels, using HPLC-UV. RESULTS: Taken together, our findings showed that 4-FBS in all 3 doses, in both sets of experiments significantly attenuated nicotine-induced behavioral sensitization in mice. Additionally, 4-FBS at 60mg/kg significantly lowered the adenosine level in the striatum. CONCLUSION: The behavioral and adenosine modulation is promising, and more receptors level studies are warranted to explore the exact mechanism of action of 4-FBS.


Subject(s)
Adenosine/antagonists & inhibitors , Behavior, Animal/drug effects , Benzene Derivatives/pharmacology , Nicotine/antagonists & inhibitors , Nicotinic Antagonists/pharmacology , Sulfonamides/pharmacology , Adenosine/metabolism , Administration, Oral , Animals , Benzene Derivatives/administration & dosage , Benzene Derivatives/chemical synthesis , Dose-Response Relationship, Drug , Injections, Intraperitoneal , Male , Mice , Mice, Inbred BALB C , Nicotine/administration & dosage , Nicotinic Antagonists/administration & dosage , Nicotinic Antagonists/chemical synthesis , Sulfonamides/administration & dosage , Sulfonamides/chemical synthesis
13.
BMC Cancer ; 17(1): 694, 2017 Oct 23.
Article in English | MEDLINE | ID: mdl-29061136

ABSTRACT

BACKGROUND: The emergence of chemoresistant cancers and toxicity related to existing chemotherapeutic agents, demand the search for new pharmacophore with enhanced anti-cancer activity and least toxicity. For this purpose, three new sesquiterpenes were isolated from ethyl acetate fraction of the aerial parts of the plant Polygonum barbatum and evaluated for their anti-cancer potential. METHODS: The structural elucidation and characterization of the isolated compounds 1-3 were performed using various spectroscopic techniques such as mass, UV, IR, and extensive 1D/2D-NMR spectroscopy. Furthermore, the compounds 1-3 were subjected to screening of anti-cancer activity against different cell lines followed by brief analysis of apoptotic and anti-angiogenic potentials of the potent hit against non-small cell lung carcinoma cell line. RESULTS: All the compounds 1-3 were subjected to anti-proliferative potential against non-small cell lung carcinoma (NCI-H460), breast cancer (MCF-7), cervical cancer (HeLa) and normal mouse fibroblast (NIH-3 T3) cell lines. Among these, compound 3 was found to be more cytotoxic against NCI-H460 and MCF-7 cells (IC50 = 17.86 ± 0.72 and 11.86 ± 0.46 µM respectively). When compared with the standard drug cisplatin compound 3 was found to have more potent activity against NCI-H460 (IC50 = 19 ± 1.24 µM) as compared to MCF-7 cell lines (IC50 = 9.62 ± 0.5 µM). Compound 3 induced apoptosis in NCI-H460 cells in a dose dependent manner. It significantly downregulated, the expression of anti-apoptotic (BCL-2 L1 and p53) and increased the expression of pro-apoptotic (BAK and BAX) genes. Besides apoptosis, it also significantly reduced the cell migration and downregulated the angiogenic genes (i.e. VEGF and COX-2), thereby, inhibiting angiogenesis in NCI-H460 cells. CONCLUSION: Compound 3 possesses potent anti-proliferative potential as well as induced apoptosis and inhibited the cell migration of the cancerous cells by altering the gene expression, responsible for it.


Subject(s)
Cell Proliferation/drug effects , Neoplasms/drug therapy , Polygonum/chemistry , Sesquiterpenes/pharmacology , Animals , Antineoplastic Agents, Phytogenic/pharmacology , Apoptosis , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/physiopathology , HeLa Cells , Humans , MCF-7 Cells , Mice , NIH 3T3 Cells , Neoplasms/physiopathology
14.
Curr Drug Metab ; 18(2): 402-403, 2017.
Article in English | MEDLINE | ID: mdl-28093995

ABSTRACT

Malaria remains one of the major public health problems worldwide and it is responsible for a large number of morbidity and mortality. Especially, in the third world countries, it is still alarming. The development of drugresistant to Plasmodium falciparum strains has further degraded the overall situation. However, a limited number of effective drugs available emphasize how essential it is to establish new anti-malarial compounds. New antimalarial agents with distinctive structures and mechanism of action from the natural origin are thus immediately required to treat sensitive and drug-resistant strains of malaria. Over the years, phytopharmaceuticals have provided numerous lead compounds. Similarly, the success rate of botanicals in terms of clinical significance is also very high. Of them, glycoside is one of the most widely distributed and emerging class of plant secondary metabolites. This review provides an outlook to recently isolated glycosides from plants with marked antimalarial effects in an in-vitro and in-vivo protocols and thus ideal candidates for clinical trials to ascertain their clinical utility and or led compounds.


Subject(s)
Antimalarials/therapeutic use , Glycosides/therapeutic use , Animals , Antimalarials/pharmacology , Drug Discovery , Glycosides/pharmacology , Humans , Malaria/drug therapy , Phytochemicals/pharmacology , Phytotherapy
15.
Appl Spectrosc ; 71(3): 456-462, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27798383

ABSTRACT

Polymers are among the most commonly used materials in our everyday life. They are generally transparent to terahertz (THz) radiation, but are quite difficult to differentiate using optical techniques as few or no characteristic features exist in the spectral range of <2.0 THz for small and portable radiation systems. In this work, we report experimental measurement of refractive indices and absorption coefficients of styrene acrylonitrile (SAN) and Bakelite in the spectral range of 0.2-2.0 THz for the first time. Additionally, we demonstrate that by combining principle component analysis (PCA) with THz time-domain spectroscopy one can differentiate such polymers. In this analysis, the first three principle components PC1, PC2, and PC3 depict >94% variance with a distribution of 72.45%, 11.52%, and 9.38%, respectively.

16.
Springerplus ; 5: 521, 2016.
Article in English | MEDLINE | ID: mdl-27186485

ABSTRACT

In the present paper, the notion of P-preinvex function is introduced and new integral inequalities for this kind of function along with beta function are establised. The work extends the results appeared in the literature.

17.
J Exp Bot ; 67(9): 2689-98, 2016 04.
Article in English | MEDLINE | ID: mdl-26969743

ABSTRACT

Potassium (K(+)) is the most important cationic nutrient for all living organisms and has roles in most aspects of plant physiology. To assess the impact of one of the main K(+) uptake components, the K(+) inward rectifying channel AKT1, we characterized both loss of function and overexpression of OsAKT1 in rice. In many conditions, AKT1 expression correlated with K(+) uptake and tissue K(+) levels. No salinity-related growth phenotype was observed for either loss or gain of function mutants. However, a correlation between AKT1 expression and root Na(+) when the external Na/K ratio was high suggests that there may be a role for AKT1 in Na(+) uptake in such conditions. In contrast to findings with Arabidopsis thaliana, we did not detect any change in growth of AKT1 loss of function mutants in the presence of NH4 (+) Nevertheless, NH4 (+)-dependent inhibition was detected during K(+) uptake assays in loss of function and wild type plants, depending on pre-growth conditions. The most prominent result of OsAKT1 overexpression was a reduction in sensitivity to osmotic/drought stress in transgenic plants: the data suggest that AKT1 overexpression improved rice osmotic and drought stress tolerance by increasing tissue levels of K(+), especially in the root.


Subject(s)
Oryza/physiology , Plant Proteins/metabolism , Potassium Channels/metabolism , Dehydration , Oryza/metabolism , Plant Proteins/physiology , Plant Roots/metabolism , Plant Shoots/metabolism , Plants, Genetically Modified , Potassium/metabolism , Potassium Channels/physiology
18.
New Phytol ; 209(3): 1040-8, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26474307

ABSTRACT

Potassium (K(+) ) is the most important cationic nutrient for all living organisms. Vacuolar two-pore K(+) (TPK) channels are important players in the regulation of cellular levels of K(+) but have not been characterised in rice. In order to assess the role of OsTPKb, a K(+) selective ion channel predominantly expressed in the tonoplast of small vacuoles, we generated overexpressing (OX) lines using a constitutive promoter and compared their phenotypes with control plants. Relative to control plants, OX lines showed better growth when exposed to low-K(+) or water stress conditions. K(+) uptake was greater in OX lines which may be driven by increased AKT1 and HAK1 activity. The enhanced K(+) uptake led to tissue K(+) levels that were raised in roots and shoots. Furthermore, energy dispersive X-ray (EDX) analyses showed a higher cytoplasm: vacuole K(+) ratio which is likely to contribute to the increased stress tolerance. In all, the data suggest that TPKb can alter the K(+) status of small vacuoles, which is important for general cellular K(+) homeostasis which, in turn, affects stress tolerance.


Subject(s)
Adaptation, Physiological , Droughts , Oryza/metabolism , Osmosis , Plant Proteins/metabolism , Potassium Channels/metabolism , Vacuoles/metabolism , Adaptation, Physiological/genetics , Gene Expression Regulation, Plant , Hydroponics , Oryza/genetics , Oryza/growth & development , Plant Leaves/metabolism , Plant Proteins/genetics , Plants, Genetically Modified , Potassium/metabolism , Potassium Channels/genetics , Real-Time Polymerase Chain Reaction , Spectrometry, X-Ray Emission , Stress, Physiological/genetics , Water
19.
Pak J Pharm Sci ; 29(5 Suppl): 1787-1794, 2016 Sep.
Article in English | MEDLINE | ID: mdl-28476703

ABSTRACT

The present study aimed to quantify the total phenolic content in Paeonia emodi rhizome methanol extract and its fractions and then evaluate the in vitro antioxidant and hepatoprotective activities of fractions rich in phenolic compounds. Maximum quantity of total phenolic content was observed in butanol (112.08±5.5 mg GAE/g dw) and chloroform fraction (107.0±3.5 mg GAE/g dw) followed by methanol extract (94.2±4.4 mg GAE/g dw), aqueous fraction (92.9±2.5 mg GAE/g dw), ethyl acetate (62.3±8.3 mg GAE/g dw) and n-hexane fraction (51.6±7.2 mg GAE/g dw). The fractions rich in total phenolic content were evaluated for in vitro antioxidant activity based on 2, 2-diphenyl-1-picryl-hydrazyl (DPPH) scavenging assay. The butanol and chloroform fraction showed significantly (P<0.05) higher radical scavenging activity with IC50 values of 6.5 and 7.05±2.5 ppm respectively. Positive correlation (R square=0.95) was observed between total phenolic content and in vitro antioxidant activity. The fractions rich in phenolic compounds were also evaluated for their hepatoprotective activity in paracetamol intoxicated mice. Five days oral administration of these fractions at a dose of 300 mg/kg body weight restored the serum ALT, AST and ALP levels of paracetamol intoxicated mice to normal level. From the results of the present research it was concluded that the butanol and chloroform fractions of P. emodi rhizome methanol extract are rich in phenolic compounds and strong antioxidant and effective in attenuation of hepatotoxicity.


Subject(s)
Antioxidants/pharmacology , Liver/drug effects , Paeonia/chemistry , Phenols/pharmacology , Plant Extracts/pharmacology , Rhizome/chemistry , Animals , Inhibitory Concentration 50 , Male , Methanol/chemistry , Mice , Phenols/analysis
20.
Ecotoxicology ; 24(6): 1259-68, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26070715

ABSTRACT

The roles of different concentrations of arsenite (As(III)) and cadmium (Cd) (0, 25 and 50 µM) in the absence and presence (1.7 mM) of phosphate (P) in tolerance and antioxidant genes expression in Oryza sativa L. were investigated. The growth parameters, metal accumulation, lipid peroxidation and soluble protein and 17 genes involved in metal accumulation and oxidative stress were measured. In our results, Lsi6 (OsNIP2;2) could play an important role in As(III) accumulation of shoots and roots in P supply (+P) and deficiency (-P) plant, while OsNRAMP5 was attributed to the part of As(III) uptake though roots under -P condition. Both of Lsi6 and OsNRAMP5 could involve Cd uptake of roots in +P plant. OsNRAMP1 was a main transporter for As(III) and Cd uptake in roots of -P plant. However, +P increased the soluble protein contents and reduced the lipid peroxidation under As(III) or Cd exposures. In As(III) exposed rice seedlings, SOD, CAT, POD, GPX, AsA-GSH cycle and GSH metabolism process were provoked to eliminate ROS induced by As(III), especially under -P condition. In Cd exposed rice seedlings, AsA-GSH cycle and GSH metabolism process played a main role in the detoxification process of plant cells, and +P could promote enzyme system activity. Furthermore, +P improve the tolerance ability of plants to tolerant 50 µM As(III) and Cd exposures compared to P deficiency.


Subject(s)
Arsenites/toxicity , Cadmium/toxicity , Gene Expression Regulation, Plant/drug effects , Oryza/genetics , Phosphates/metabolism , Antioxidants/metabolism , Oryza/drug effects , Oryza/metabolism , Oxidative Stress/drug effects , Seedlings/drug effects , Seedlings/genetics , Seedlings/metabolism
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