Showing papers by "Annamalai University published in 2014"
TL;DR: An evaluation is made on the current status of research on marine actinobacteria yielding pharmaceutically active secondary metabolites, which may form the basis for synthesis of new drugs that could be used to combat resistant pathogens.
311 citations
TL;DR: Silver nanoparticles showed remarkable cytotoxicity activity against KB cell line with evidence of high therapeutic index value are the results are discussed.
192 citations
TL;DR: Pure titanium di-oxide nanoparticles were synthesized by sol-gel technique at room temperature with appropriate reactants by tetraisopropyl orthotitanate and 2-propanol as common starting materials and the product was annealed at 450 °C for 4 h.
183 citations
TL;DR: In this paper, a total of 87 groundwater samples were collected from bore wells for two different seasons, viz., Pre monsoon and Post monsoon, and analyzed for major cations and anions.
181 citations
TL;DR: EDS result showed that the amount of Ni in the product is about 9%, these Ni doped hexagonal nanorods exhibits a blue shifts and weak (UV) emission peak, compared with pure ZnO, which may be induced by the Ni-doping different concentrations.
133 citations
TL;DR: An investigation on Fe-doped ZnO nanopowder synthesized by co-precipitated method annealed at 550°C showed a decrease in the energy gap with increasing Fe content, probably due to an increase in the lattice parameters.
130 citations
TL;DR: In this paper, the authors reported the preparation of nanobundle-shaped BiVO4-ZnO photocatalyst by a simple hydrothermal process followed by thermal decomposition.
Abstract: Development of coupled semiconductor oxides makes a significant advancement in catalytic functional materials. In this article, we report the preparation of nanobundle-shaped BiVO4–ZnO photocatalyst by a simple hydrothermal process followed by thermal decomposition. The photocatalyst was characterized by X-ray powder diffraction (XRD), high-resolution scanning electron microscopy (HR-SEM), field emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy (EDS), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy (XPS), photoluminescence spectroscopy (PL), and UV–vis diffuse reflectance spectroscopy (DRS). The XRD pattern confirmed formation of monoclinic scheelite BiVO4 and the hexagonal wurtzite structure of ZnO. HR-SEM images show nanobundle-like structure, and the size of the nanospheres ranges from 20 to 40 nm. BiVO4–ZnO has increased absorption in the UV and visible region when compared to ZnO. The cata...
123 citations
TL;DR: This review has focused attention on the bioactive natural products isolated from marine actinobacteria, possessing unique chemical structures that may form the basis for synthesis of novel drugs that could be used to combat resistant pathogenic microorganisms.
120 citations
TL;DR: In this paper, gold nanoparticles (Au-NPs) were synthesized at room temperature using Solanum nigrum (S.nigrum ) leaf extract as reducing agent.
119 citations
TL;DR: In this paper, the authors report on recent developments in homogeneous Advanced Oxidation Processes (AOPs) for the treatment of water and wastewater for degradation and mineralization of recalcitrant pollutants.
Abstract: This paper reports on recent developments in homogeneous Advanced Oxidation Processes (AOPs) for the treatment of water and wastewater. It has already been established that AOPs are very efficient compared to conventional treatment methods for degradation and mineralization of recalcitrant pollutants present in water and wastewater. AOPs generate a powerful oxidizing agent, hydroxyl radical, which can react with most of the pollutants present in wastewater. Therefore, it is important to discuss recent developments in AOPs. The homogeneous AOPs such as O3, UV/O3, UV/O3/H2O2, and UV/H2O2, Fe2
118 citations
TL;DR: This work proposes a genetically based PID controller tuned with fixed PID parameters that tends to operate the CSTR process in its entire operating range to overcome the limitations of the linear PID controller.
Abstract: Genetic algorithm (GA) based PID (proportional integral derivative) controller has been proposed for tuning optimized PID parameters in a continuous stirred tank reactor (CSTR) process using a weighted combination of objective functions, namely, integral square error (ISE), integral absolute error (IAE), and integrated time absolute error (ITAE). Optimization of PID controller parameters is the key goal in chemical and biochemical industries. PID controllers have narrowed down the operating range of processes with dynamic nonlinearity. In our proposed work, globally optimized PID parameters tend to operate the CSTR process in its entire operating range to overcome the limitations of the linear PID controller. The simulation study reveals that the GA based PID controller tuned with fixed PID parameters provides satisfactory performance in terms of set point tracking and disturbance rejection.
TL;DR: This review made an attempt to clearly describe the beneficial effects of various types of berries as promising neuroprotective agents.
TL;DR: Evidence is provided that dietary astaxanthin prevents the development and progression of HBP carcinomas through the inhibition of JAK-2/STAT-3 signaling and its downstream events and astaxAnthin that functions as a potent inhibitor of tumour development and progress by targeting JAK/STAT signaling may be an ideal candidate for cancer chemoprevention.
Abstract: Identifying agents that inhibit STAT-3, a cytosolic transcription factor involved in the activation of various genes implicated in tumour progression is a promising strategy for cancer chemoprevention. In the present study, we investigated the effect of dietary astaxanthin on JAK-2/STAT-3 signaling in the 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis model by examining the mRNA and protein expression of JAK/STAT-3 and its target genes. Quantitative RT-PCR, immunoblotting and immunohistochemical analyses revealed that astaxanthin supplementation inhibits key events in JAK/STAT signaling especially STAT-3 phosphorylation and subsequent nuclear translocation of STAT-3. Furthermore, astaxanthin downregulated the expression of STAT-3 target genes involved in cell proliferation, invasion and angiogenesis, and reduced microvascular density, thereby preventing tumour progression. Molecular docking analysis confirmed inhibitory effects of astaxanthin on STAT signaling and angiogenesis. Cell culture experiments with the endothelial cell line ECV304 substantiated the role of astaxanthin in suppressing angiogenesis. Taken together, our data provide substantial evidence that dietary astaxanthin prevents the development and progression of HBP carcinomas through the inhibition of JAK-2/STAT-3 signaling and its downstream events. Thus, astaxanthin that functions as a potent inhibitor of tumour development and progression by targeting JAK/STAT signaling may be an ideal candidate for cancer chemoprevention.
TL;DR: The photocatalytic activity of Ag-Au-ZnO was investigated for the degradation of Methylene Blue (MB) in aqueous solution using UV-A light.
TL;DR: In this article, the dissolution rate and stability of a poorly water-soluble drug quercetin by complexation with cyclodextrin-based nanosponges were investigated.
Abstract: Quercetin is a flavonoid widely distributed in vegetables and fruits and exhibits strong antioxidant activity, but the poor solubility and stability of quercetin limit its function and application The purpose of this study was to enhance the dissolution rate and stability of a poorly water-soluble drug quercetin by complexation with cyclodextrin-based nanosponges Nanosponges are recently developed sponge-like structures and have the capacity to interact with small molecules in its matrix In this study, five types of nanosponges were purposely designed by varying the molar ratio of β-cyclodextrin and diphenyl carbonate Quercetin was loaded into nanosponges by freeze-drying method The particle sizes of plain and quercetin-loaded nanosponges are in between 40 and 100 nm with low polydispersity indices Zeta potential is sufficiently high to obtain a stable colloidal nanosuspension Fourier transformed infrared, Raman spectroscopy, differential scanning calorimetry, and X-ray powder diffraction studies confirmed the interaction of quercetin with nanosponges Particle sizes measured from TEM images were in agreement with DLS results The dissolution of the quercetin nanosponges was significantly higher compared with the pure drug The stability of encapsulated quercetin nanosponge was tracked in a simulated intestinal fluid A marked improvement in the photostability was also observed In addition, the antioxidant activity of the quercetin nanosponges was more effective than pure quercetin on DPPH scavenging, anti-superoxide formation, and superoxide anion scavenging These results signify that nanosponge formulations can be used as effective nanocarriers for the delivery of quercetin
TL;DR: In this article, the antioxidant and anticancer activities of bioactive peptide isolated from oyster protein hydrolysate were evaluated in vitro and the peptide exhibited a strong antioxidant potential as a DPPH scavenger.
TL;DR: In this article, the nano-sized silver nanoparticles were formed by the reduction of silver nitrate to aqueous silver metal ions during exposure to the extract of marine seaweed Sargassum wightii.
Abstract: In this paper, we have reported on biological synthesis of nano-sized silver and its antibacterial activity against human pathogens. The nanoparticles of silver were formed by the reduction of silver nitrate to aqueous silver metal ions during exposure to the extract of marine seaweed Sargassum wightii. The optical properties of the obtained silver nanoparticles were characterized using UV–visible absorption and room temperature photoluminescence. The X-ray diffraction results reveal that the synthesized silver nanoparticles are in the cubic phase. The existence of functional groups was identified using Fourier transform infrared spectroscopy. The morphology and size of the synthesized particles were studied with atomic force microscope and high-resolution transmission electron microscope measurements. The synthesized nanoparticles have an effective antibacterial activity against S. aureus, K. pneumoniae, and S. typhi.
Victoria University of Wellington1, National Research University – Higher School of Economics2, Monash University3, Lingnan University4, Annamalai University5, Arab Open University6, Nagoya University7, University of Karachi8, Nanyang Technological University9, Chonnam National University10, National Chung Cheng University11
TL;DR: Using multigroup confirmatory factor analysis and multilevel modeling, this paper investigated the measurement invariance, cross-level isomorphism, predictive validity, and nomological network of the fear of happiness scale across 14 nations.
Abstract: A survey of the cultural notions related to happiness and the existing empirical evidence indicate that some individuals endorse the belief that happiness, particularly an immoderate degree of it, should be avoided. These beliefs mainly involve the general notion that happiness may lead to bad things happening. Using multigroup confirmatory factor analysis and multilevel modeling, this study investigates the measurement invariance, cross-level isomorphism, predictive validity, and nomological network of the fear of happiness scale across 14 nations. The results show that this scale has good statistical properties at both individual and cultural levels. The findings also indicate that this scale has the potential to add to the knowledge about how people conceive of, and experience, happiness across cultures.
TL;DR: The present findings indicated the potential of mahua oil cake as suitable substrate for the production of rhamnolipids in SSF by S. rubidaea SNAU02 and application potential of the biosurfactant produced as biocontrol agent against plant pathogens.
TL;DR: Panicum sumatrense possess many growth and physiological drought tolerance characters which can be used in future breeding program.
Abstract: Drought stress is one of the abiotic stresses and it may alter plant growth, metabolism and yield. The present study aims to analyze the growth, chlorophyll pigments, osmotic adjustment and antioxidative enzymes activity in Panicum sumatrense under drought stress. The control was irrigated daily and treated plants were irrigated at 4-, 7-, 10-, 13-day intervals. Later, they were irrigated at 3-day interval up to 70 DAS. The root and leaf samples were collected on 30 DAS, 50 DAS and 70 DAS and used for analysis. The root length increased gradually in all drought treatments at all growth stages of P. sumatrense. The chlorophyll pigments and plant height showed a reduction in 13 DID treatment when compared to all treatment. Compatible solutes like proline, glycine betaine and free amino acid increased in all drought treatment when compared to control at 70 DAS. Furthermore, stress treatment caused an increase in activity of antioxidant enzymes like superoxide dismutase, catalase and peroxidase. Panicum sumatrense possess many growth and physiological drought tolerance characters which can be used in future breeding program.
TL;DR: The ability of bacteriocin in inhibiting a wide-range of pathogenic bacteria is of potential interest for food safety and may have future applications in food preservative.
Abstract: Objective
To study the production, purification and characterization of bacteriocin from Lactobacillus murinus AU06 isolated from marine sediments and its broad spectrum of inhibition against fish pathogens.
TL;DR: Design of highly efficient phosphorescent emitters based on metal- and heavy atom-free boron compounds has been demonstrated by taking advantage of the singlet fission process.
Abstract: Design of highly efficient phosphorescent emitters based on metal- and heavy atom-free boron compounds has been demonstrated by taking advantage of the singlet fission process. The combination of a suitable molecular scaffold and appropriate electronic nature of the substituents has been utilized to tailor the phosphorescence emission properties in solution, neat solid, and in doped PMMA thin films.
TL;DR: It is suggested that lyophilized probiotic B. cereus at a concentration of 0.4%/100 g feed was efficient in stimulating the growth and immunity in shrimp, when compared to that of other diets fed shrimp.
TL;DR: Findings suggest that alleviation of inflammation and ER stress by ASX could be a mechanism responsible for its beneficial effect in this model and may be a promising treatment strategy for insulin resistant patients.
Abstract: We recently showed that astaxanthin (ASX), a xanthophyll carotenoid, activates phosphatidylinositol 3-kinase pathway of insulin signaling and improves glucose metabolism in liver of high fructose–fat diet (HFFD)-fed mice. The aim of this study is to investigate whether ASX influences phosphorylation of c-Jun-N-terminal kinase 1 (JNK1), reactive oxygen species (ROS) production, endoplasmic reticulum (ER) stress, and inflammation in liver of HFFD-fed mice. Adult male Mus musculus mice were fed either with control diet or HFFD for 15 days. After this period, mice in each group were divided into two and administered ASX (2 mg/kg/day, p.o) in 0.3 ml olive oil or 0.3 ml olive oil alone for the next 45 days. At the end of 60 days, liver tissue was excised and examined for lipid accumulation (Oil red O staining), intracellular ROS production, ER stress, and inflammatory markers. Elevated ROS production, lipid accumulation, and increased hepatic expression of ER stress markers such as Ig-binding protein, PKR-like ER kinase, phosphorylated eukaryotic initiation factor 2α, X-box binding protein 1, activating transcription factor 6, and the apoptotic marker caspase 12 were observed in the liver of the HFFD group. ASX significantly reversed these changes. This reduction was accompanied by reduced activation of JNK1 and I kappa B kinase β phosphorylation and nuclear factor-kappa B p65 nuclear translocation in ASX-treated HFFD mice. These findings suggest that alleviation of inflammation and ER stress by ASX could be a mechanism responsible for its beneficial effect in this model. ASX could be a promising treatment strategy for insulin resistant patients.
TL;DR: In this paper, the effect of surface treatment by BP on tensile and flexural properties of BSF reinforced PLA composites was investigated by means of UTM and morphological analysis.
Abstract: The work focuses on the influencing effect of fiber surface treatment by BP towards mechanical properties of BSF reinforced PLA composites. BSF were treated by BP to improve the adhesion between fibres and matrix. BSF (30 wt %) reinforced PLA (70 wt %) hybrid composites were fabricated by means of twin screw extrusion followed by injection molding process. Tensile strength, flexural strength and modulus were tested by means of UTM. The morphological analysis of the untreated and treated BSF reinforced PLA composites in comparison with virgin PLA was carried out by SEM to examine the existence of interfacial adhesion between BSF and PLA. The resultant data reveals that treated BSF restricts the motion of the PLA matrix due to better wettability and bonding. Consequently, mechanical properties like tensile and flexural moduli of BSF reinforced PLA composites were enhanced in comparison to virgin PLA and untreated BSF reinforced PLA composites. The results are discussed in detail.
TL;DR: The composite nanosheets are photostable, reusable, and magnetically recoverable, revealing potential application in mineralization of organic pollutants.
Abstract: Fe3O4-implanted ZnO and pristine ZnO nanosheets have been synthesized hydrothermally High-resolution scanning electron microscopy, high-resolution transmission electron microscopy, energy dispersive X-ray spectroscopy, elemental mapping, selected area electron diffractometry, powder X-ray diffractometry, Raman spectroscopy, vibrating sample magnetometry, solid state impedance spectroscopy, UV–visible diffuse reflectance spectroscopy, and photoluminescence spectroscopy show implantation of Fe3O4 in ZnO nanosheets Fe3O4 core with ZnO shell is of type I core/shell heterostructure which is to quench charge carriers and suppress photocatalysis But the photocatalytic activity is not suppressed on implantation of Fe3O4 in ZnO nanosheets, and time controlled single photon counting lifetime spectroscopy shows that the photogenerated charge carriers are not quenched by the Fe3O4 core in the ZnO nanosheets The composite nanosheets are photostable, reusable, and magnetically recoverable, revealing potential appli
TL;DR: Analysis suggests that the obtained silver nanoparticles might be stabilized through the interactions of carboxylic groups, carbonyl groups and the flavonoids present in the T. terrestris extract.
TL;DR: In this article, the use of pine oil in a diesel engine without resorting to any engine modifications has been studied, and two ignition promoters, IAN (iso-amyl nitrate) and DTBP (di-tertiary butyl peroxide), have been proposed.
TL;DR: Prevalence of self-medication was high primarily among illiterate males aged above 15 years with a low income and there is a need for planning interventions to promote rational self-Medication through mass medias such as newspaper, magazine and TV.
Abstract: Background: Many of the studies have investigated the prevalence and nature of selfâÂÂmedication. It is a common type of selfâÂÂcare behavior among the populace of various countries. World Health Organization promotes the practice of selfâÂÂmedication for effective and quick relief of symptoms without medical consultations to reduce the burden on healthâÂÂcare services, which are often understaffed and inaccessible in rural and remote areas. Aim: The aim of the study was to determine the extent and pattern of selfâÂÂmedication among the population (patients) attending pharmacies at study sites and to note the association of selfâÂÂmedication variables with demographic factors. Subjects and Methods: The present study was a community based cross sectional study aimed to gather information about the prevalence of selfâÂÂmedication in the rural town of Sahaswan, Uttar Pradesh from June 2012 to July 2012. The sample size comprised of 600 respondents. Data were collected through a prepared questionnaire. All descriptive data were coded, entered and analyzed using the statistical package for Social sciences program version 17.0 (Chicago, IL, USA). Descriptive data analysis was conducted and reported as frequencies and percentage. Results: The percentage of patients who were seeking selfâÂÂmedication was approximately 50% (300/600). Most of the patients were seeking selfâÂÂmedication for headache and other pain (23.3% [140/600]), fever (14.5% [87/600]), urinary tract infections (9.7% [58/600]) and respiratory tract infections (11.7% [70/600]). The drugs most commonly purchased for practicing selfâÂÂmedication were nonâÂÂsteroidal antiâÂÂinflammatory drugs (25.3% [152/600]), medications used for gastro intestinal problems (20.8% [125/600]) and antibiotics (16.7% [100/600]). Conclusion: Prevalence of selfâÂÂmedication was high primarily among illiterate males aged above 15 years with a low income. Patient health awareness programs, assistance by community pharmacists and pharmacist continuing education are necessary for controlling selfâÂÂmedication. There is a need for planning interventions to promote rational selfâÂÂmedication through mass medias such as newspaper, magazine and TV.
TL;DR: In this article, a simple chemical precipitation method for the preparation of undoped and cerium doped ZnO nanocrystals was reported, where the concentration of cerium in the products can be controlled in the range of 0.025 − 0.125 mol.