Rajalakshmi R.,Avinashilingam University For Women
Asian Journal of Chemistry | Year: 2012
Inhibitive properties of leaf sheath extract of cocos nucifera for the corrosion of mild steel were studied using conventional weight loss and electrochemical measurements of monitoring corrosion. The results revealed that leaf sheath extract of cocos nucifera inhibited the corrosion of mild steel. The inhibitor was found to function by being adsorbed on the surface of mild steel. The adsorption of the inhibitor followed the Langmuir and Temkin type adsorption isotherm. Optical images of the corrosion product (without inhibitor) and the corrosion product (with the inhibitor) confirmed that the inhibitor is an adsorption inhibitor. Physical adsorption mechanism at low temperature and chemical adsorption mechanism at high temperature had been proposed from the values of thermodynamic parameters obtained. Electrochemical studies reveal that the plant extracts act as mixed type inhibitors. Optical electron microscope and FTIR were carried out to confirm the investigated inhibitor was adsorbed on mild steel surface. The leaf sheath extract of cocos nucifera in HCl medium proved to be zero cost inhibitor, eco-friendly, non-toxic and highly economical.
Sreelatha S.,National University of Singapore |
Sreelatha S.,Avinashilingam University For Women |
Jeyachitra A.,Madurai Kamaraj University |
Padma P.R.,Avinashilingam University For Women
Food and Chemical Toxicology | Year: 2011
Medicinal plants provide an inexhaustible source of anticancer drugs in terms of both variety and mechanism of action. Induction of apoptosis is the key success of plant products as anticancer agents. The present study was designed to determine the antiproliferative and apoptotic events of Moringa oleifera leaf extract (MLE) using human tumor (KB) cell line as a model system. KB cells were cultured in the presence of leaf extracts at various concentrations for 48. h and the percentage of cell viability was evaluated by MTT assay. MLE showed a dose-dependent inhibition of cell proliferation of KB cells. The antiproliferative effect of MLE was also associated with induction of apoptosis as well as morphological changes and DNA fragmentation. The morphology of apoptotic nuclei was quantified using DAPI and propidium iodide staining. The degree of DNA fragmentation was analyzed using agarose gel electrophoresis. In addition, MLE at various concentrations was found to induce ROS production suggesting modulation of redox-sensitive mechanism. Eventually, HPTLC analysis indicated the presence of phenolics such as quercetin and kaempferol. Thus, these findings suggest that the leaf extracts from M. oleifera had strong antiproliferation and potent induction of apoptosis. Thus, it indicates that M. oleifera leaf extracts has potential for cancer chemoprevention and can be claimed as a therapeutic target for cancer. © 2011 Elsevier Ltd.
Geetha G.,Avinashilingam University For Women |
Geethalakshmi S.N.,Avinashilingam University For Women
Procedia Engineering | Year: 2012
This paper presents a novel technique for removing the artifacts from the ElectroEncephaloGram (EEG) signals. EEG signals are influenced by different characteristics, like line interference, EOG (electro-oculogram) and ECG (electrocardiogram). The elimination of artifact from scalp EEGs is of substantial significance for both the automated and visual examination of underlying brainwave actions. These noise sources increase the difficulty in analyzing the EEG and obtaining clinical information related to pathology. Hence it is crucial to design a procedure to decrease such artifacts in EEG records. This paper uses Spatially-Constrained Independent Component Analysis (SCICA) to separate the Independent Components (ICs) from the initial EEG signal. As the next step, Wavelet Denoising (WD) is applied to extract the brain activity from purged artifacts, and finally the artifacts are projected back and subtracted from EEG signals to get clean EEG data. Here, thresholding plays an important role in delineating the artifacts and hence a better thresholding technique called Otsu', thresholding is applied. Experimental results show that the proposed technique results in better removal of artifacts.
Rama Prabha M.,Avinashilingam University For Women |
Vasantha K.,Government of Tamilnadu
Journal of Applied Pharmaceutical Science | Year: 2011
Oxidative stress has been implicated with the pathology of many diseases such as inflammatory conditions, cancer, diabetes and aging. In view of that an attempt was made to evaluate free radical scavenging activity, cytotoxic activity and polyphenolic content of methanolic extract of Calotropis procera flowers.Free radical scavenging activity was estimated using in vitro models like 1,1,-diphenyl-2- picryl hydrazyl (DPPH), hydroxyl radical, hydrogen peroxide radical, reducing power and ferric thiocyanate method. Cytotoxicity was analysed following MTT assay using Hep2 and Vero cell lines and polyphenols were estimated using standard methods. Two way ANOVA was used for statistical analyses. The methanol extract of C. procera at 500 μg/ml showed better scavenging activity in ferric thiocyanade method (83.63 %) with the lowest IC50 of 100 μg/ml followed by hydrogen peroxide, hydroxyl radical scavenging and least activity was found to be present in DPPH assay (50.82 %). The extract had 100 % cytotoxicity on Hep2 cell lines. Flavonoids were found in greater amount than phenols and found to be had higher correlation with antioxidant activities. It was suggested that the flowers of C. procera possess in vitro antioxidant, cytotoxic activities and thus having much therapeutic value because of their polyphenolic content.
Nisha M.K.,Avinashilingam University For Women
International Journal of Pharma and Bio Sciences | Year: 2016
The present investigation was carried out to study the application and the competitiveness of commercial and purified pectinase obtained from Paecilomyces variotii. The fruit juices (grapes and pomegranate) were carried out at different enzyme concentrations (0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5) and incubation time (30, 60, 90, 120 and 160 minutes) at constant temperature (50°C) to optimize the enzymatic treatment for the yield and clarity of the juices. The optimum conditions recommended for enzymatic (crude, purified and commercial pectinase) treatment for clarification and yield of fruit juices were 3.5 mg/20g pulp of enzyme concentration and 180 min incubation time at a constant temperature of 50°C. It was observed that purified pectinase obtained from pectinolytic fungus, P. variotii enhanced juice yield and clarity of grape and pomegranate juices and is on par with the commercial pectinase when compared to untreated juices. A maximum yield of 79% and clarity of 19.4 and 19.5% were obtained from grape juice and a significantly high yield of 74% and clarity of 4.9 and 4.8 were acheived from pomegranate juice when compared to the unclarified grape and pomegranate juices (60 and 52% respectively). There was an increase in the yield of 31.6% and 42.3% of the grape and pomegranate juices respectively when treated with purified enzyme than the untreated juices.
Leelavathi S.,Avinashilingam University For Women |
Rajalakshmi R.,Avinashilingam University For Women
Journal of Materials and Environmental Science | Year: 2013
There is a growing trend to utilize plant extracts and pharmaceutical compounds as corrosion inhibitors. the inhibitive performance of extract of dodonaea viscosa leaves (DLVE) on the corrosion of mild steel in 1M HCL and 0.5m H2SO4 were studied using mass loss and electro chemical measurements. characterization of DLVE wascarried out using gc-ms and ft-ir spectroscopy. results confirmed that the extract of dodonaea viscosa leaves (DVLE) acts as an effective corrosion inhibitor in theacid environment. the inhibition efficiency increased with increase in concentration of the inhibitor and decreased with temperature. thermodynamic parameters revealed that the inhibition is through spontaneous adsorption of inhibitors onto the metal surface. potentiodynamic polarization and electrochemical impedance studies confirmed that the system follows mixed mode of inhibition. adsorbed film of inhibitor at metal /solution interface has been confirmed using reflectance fourier transform infrared spectroscopy. surface analysis by uv, ftir and sem confirmed the formation of protective layer on the mild steel (MS) surface. efforts were also taken to propose a suitable mechanism for the inhibition.
Geethanjali S.,Avinashilingam University For Women |
Subash A.,Avinashilingam University For Women
Enzyme Research | Year: 2013
The purified fish visceral protease enzyme was immobilized by using various concentrations of sodium alginate and calcium chloride to optimize the best concentration for the formation of the beads. Then it was characterized by assaying the optimal pH, temperature, storage stability and reusability. The results on immobilization with sodium alginate and calcium chloride showed that a combination of 2% sodium alginate and 0.3 M calcium chloride weas found to be the optimum concentration for the formation of spherical and stable beads, this gave a maximal entrapped activity of 48.31%, and there was no change in the optimum pH 8.0 and temperature 40°C of protease before and after entrapment. The results on stability and reusability indicated that it was stable at 4°C retaining 100% residual activity after 5 days of storage and 67% loss of activity after ten days of storage and it retained 100% residual activity on the first reuse, 75% residual activity on the second reuse, 25% residual activity on the third use and complete loss in the activity on the fourth reuse. © 2013 S. Geethanjali and Anitha Subash.
Ali Fathima Sabirneeza A.,Avinashilingam University For Women |
Subhashini S.,Avinashilingam University For Women
Journal of Applied Polymer Science | Year: 2013
A novel water-soluble conducting polymer composite, poly(vinyl alcohol-histidine) was synthesized from aqueous solution by free radical condensation using persulfate. The composite was characterized using UV-Visible, Fourier transform infrared, scanning electron microscopy, thermogravimetric analysis (TG/DTG), and differential scanning calorimetry techniques while its AC conductance was measured by LCZ analyzer. The inhibitive action of the composite on the corrosion behavior of mild steel in 1M HCl was studied by conventional weight loss method, potentiodynamic polarization studies (Tafel), linear polarization studies, and electrochemical impedance spectroscopy. The effects of inhibitor concentrations, exposure time, and temperature have been investigated. The corrosion rate, inhibition efficiency (IE), and other parameters have been evaluated for different inhibitor concentrations. The composite provided more than 95% IE at an optimum concentration of 0.6% by weight. The results showed the composite as an effective mixed type inhibitor. The adsorption of this inhibitor obeyed Temkin adsorption isotherm. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 Copyright © 2012 Wiley Periodicals, Inc.
Firdhouse M.J.,Avinashilingam University For Women |
Lalitha P.,Avinashilingam University For Women
Asian Journal of Pharmaceutical and Clinical Research | Year: 2013
In order to implement green chemistry techniques in the synthesis of silver nanoparticles and to focus on the importance of plant sources available world-wide, an eco-friendly method of synthesis of silver nanoparticles using aqueous extract of Portulaca oleracea was carried out. Rapid synthesis of silver nanoparticles was seen in sonication method comparing room temperature and higher temperature conditions. The completion of the formation of silver nanoparticles was monitored by UV-visible spectroscopy. The particle size of the synthesized silver nanoparticles was found to be less than 60 nm and confirmed by XRD, Scherrer's formula and SEM analysis.
Uma M.,Avinashilingam University For Women |
Padmavathi G.,Avinashilingam University For Women
International Journal of Network Security | Year: 2013
The role of computers and the Internet in modern society is well recognized. Recent developments in the fields of networking and cyberspace have greatly benefited mankind, but the rapid growth of cyberspace has also contributed to unethical practices by individuals who are bent on using the technology to exploit others. Such exploitation of cyberspace for the purpose of accessing unauthorized or secure information, spying, disabling of networks and stealing both data and money is termed as cyber attack. Such attacks have been increasing in number and complexity over the past few years. There has been a dearth of knowledge about these attacks which has rendered many individuals/agencies/organizations vulnerable to these attacks.  Hence there is a need to have comprehensive understanding of cyber attacks and its classification. The purpose of this survey is to do a comprehensive study of these attacks in order to create awareness about the various types of attacks and their mode of action so that appropriate defense measures can be initiated against such attacks.