Vel Technology Multitech

Chennai, India

Vel Technology Multitech

Chennai, India
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Chandrika M.,Sathyabama University | Chellaram C.,Vel Technology Multitech | Chellaram C.,Tamil University
Der Pharmacia Lettre | Year: 2015

The present study aims at investigating the phytochemical composition, tannin content and antibacterial activity of leaf extracts of Borreria hispida. Phytochemical screening of various extracts such as aqueous, ethanol, chloroform, acetone and petroleum ether of leaf extracts, revealed the presence of tannins, saponins, phenols, flavonoids, cardiac glycosides, terpenoids, alkaloids and steroids. The leaf extracts were evaluated for tannins content with tannic acid as standard. The optimum yield of tannins was found in ethanol leaf extract (42mg TAE/g) of Borreria hispida. Different concentrations of ethanolic leaf extracts were tested for the anti-bacterial activity against Bacillus subtilis, B. cereus, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli using the agar disc diffusion technique. The 75% ethanolic extracts from dry powdered leaf of Borreria hispida had superior level of antimicrobial activity. The powerful antibacterial effect is attributed to the greater amount of tannins compound in the ethanolic leaf extracts of Borreria hispida.


Chellaram C.,Vel Technology Multitech | Chellaram C.,Vel Technology University Avadi
International Journal of PharmTech Research | Year: 2015

Bacteria are common populace of surfaces and the internal tissues of most plants. These bacteria contribute to the health, growth and development of plants. In this study, 45 strains were isolated from Phyllanthus niruri plant leaves. Phyllanthus niruri is a medicinal plant used popularly to cure jaundice. Endophytic bacteria isolated were tested against human pathogens and the active strain was identified. Ethyl acetate extract of the strain 13 shows activity against Candida albicans, Klebsiella pneumoniae and Escherichia coli. High Performance Liquid Chromatography (HPLC) and Matrix Assisted Laser Desorption Ionization – Time of Flight (MALDI-TOF) analysis were done. The data shows the presence of active compounds. Thus, the endophytic bacteria may yield a vast array of new compounds with novel activities that will provide new drugs in the fight against a number of pathogens currently resistant to conventional antibiotic therapies. © 2015, Sphinx Knowledge House. All Right reserved.


Gladis Raja Malar C.,Sathyabama University | Chellaram C.,Vel Technology Multitech | Chellaram C.,Vel Technology University Avadi
Der Pharmacia Lettre | Year: 2015

The study was conducted to determine the antioxidant activity, total phenol and flavonoid content of the stem of Salacia oblonga, collected from five geographically distant regions of Western Ghat, Karnataka were examined using extracts of aqueous, ethanol, methanol, chloroform and petroleum ether. The five different solvent extracts of S. oblonga stem were evaluated for antioxidant activities by DPPH (1,1 - diphenyl-2-picryl-hydrazyl) radical scavenging activity using Butylated Hydroxy Toluene (BHT) as standard. Among five accessions with different solvents used, maximum antioxidant activity was found in aqueous stem extract (84.3 %) from Hubli(2) followed by others. Total phenol and flavonoid contents were quantitatively estimated. The aqueous stem extract of Salacia oblonga (Hubli(2) - Karnataka) was found maximum in total phenol and flavonoid contents were 34.63 mg GAE /g and 18.72 mg QE /g respectively. The aqueous stem extracts of S. oblonga had superior level of antioxidant activity. The powerful free radical scavenging effect is attributed to the greater amount of phenol and flavonoid compounds in the aqueous stem extract.


Mani P.K.,Vel Technology Multitech | Naidu K.S.,Vel Technology University
ARPN Journal of Engineering and Applied Sciences | Year: 2015

For the power quality improvement of the system FACTS devices like static synchronous compensator (STATCOM), static synchronous series compensator(SSSC), interline power flow controller (IPFC), and unified power flow controller (UPFC) etc. are introduced. These devices are used for the transmission system. But now a day's these FACTS devices are used for distribution system and called as custom power devices. The main custom power devices which are used in distribution system for power quality improvement are distribution static synchronous compensator (DSTATCOM), dynamic voltage Restorer (DVR), active filter (AF), unified power quality conditioner (UPQC) etc. In this paper, for power quality improvement in the distribution system, DVR is used with Fuzzy logic controller. There are two different loads are considered. One is linear load and the other is nonlinear load (induction motor). With these loads different fault situations are created and DVR performances are analyzed. © 2006-2015 Asian Research Publishing Network (ARPN).


Manila P.K.,Vel Technology Multitech | Siddappa Naidu K.,Vel Technology University
ARPN Journal of Engineering and Applied Sciences | Year: 2016

This paper presents a Fuzzy Logic Control Based (FLCB) Shunt Active Filter (SAF) capable of reducing the total harmonics distortion (THD) in Power System (PS). SAF is one of the key controllers in Flexible Alternating Current Transmission System (FACTS) to control the transmission line voltage and can be used in PS to enhance the power transmission capacity and extend the transient stability. In order to improve the power factor, compensate the reactive power and suppress the total harmonic distortion (THD) drawn from a Non-Linear Diode Rectifier Load (NLDRL) of SAF, we propose a Hysteresis Current Pulse Width Modulation (HCPWM) technique which is used as control for the switches of the Voltage Source Inverter (VSI) or SAF. The synchronous reference D-Q frame theory is used to generate the reference compensating currents for SAF. A fuzzy logic based control is developed to regulate the voltage of the DC capacitor. The system with control scheme is implemented in MATLAB/Simulink. The simulation results show the effectiveness of the proposed method for harmonic damping and voltage regulation. © 2006-2016 Asian Research Publishing Network (ARPN).


Mani P.K.,Vel Technology Multitech | Siddappa Naidu K.,Vel Technology University
ARPN Journal of Engineering and Applied Sciences | Year: 2016

Power quality has become an important factor in power systems, for consumer and household appliances with proliferation of various electric and electronic equipment and computer systems. The main causes of a poor power quality are harmonic currents, poor power factor, supply-voltage variations, etc. A technique of achieving both active current distortion compensation, power factor correction and also mitigating the supply-voltage variation at the load side is compensated by unique devices S-D (STATCOM and DVR) in this paper. The proposed S-D system can improve the power quality at the point of common coupling on power distribution systems under unbalanced and distorted load conditions. The STATCOM is connected across the load to compensate for current-related problems such as reactive power compensation. The series component of the S-D device is Dynamic Voltage Restorer which inserts a voltage so as to maintain the voltage at the load terminals balanced and free of distortion. © 2006-2016 Asian Research Publishing Network (ARPN).


Chellaram C.,Vel Technology Multitech | Alex John A.,St Peters University
Asian Journal of Pharmaceutical and Clinical Research | Year: 2015

Objective: To screen and isolate peptide antibiotics producing epibiotic bacteria from the surface of the sea fan Juncella juncea, and partially purify the active compound. Methods: In this study, epibiotic bacteria were isolated by swabbing a small area of the coral surface with a sterile cotton swab, which was then directly swabbed on to Zobell marine agar plates. Antibiotic production was screened using agar overlay method and the active peptide was partially purified using anion exchange chromatography and reversed phase high-performance liquid chromatography (RP-HPLC). Phylogenetic identification based on comparative sequence analysis of 16Ss rRNA gene indicated that the stain fell under the genera Streptomyces. Results: In the initial screening using agar overlay method the strain was found to exhibit broad spectral activity exhibiting both antibacterial and antifungal activities. Protease digestion of the crude extract resulted in the loss of activity indicating the proteinaceous nature of the active molecules. Bioassay guided purification using anion exchange chromatography, and RP-HPLC was carried and the active peptide was partially purified. An epibiotic Streptomyces strain CN3 producing potent broad spectral peptide was isolated. Conclusion: This study highlights the importance of epibiotic bacteria associated with corals as a potential source for the discovery of novel antimicrobials and other natural products. © 2015, Asian Journal of Pharmaceutical and Clinical Research. All rights reserved.


Mohana Sundaram K.,Vel Technology MultiTech | Sugavanam K.R.,Vel Technology HighTech | Senthil Kumar R.,Vel Technology HighTech
ARPN Journal of Engineering and Applied Sciences | Year: 2015

This paper analyze an effective comparison between Pulse width modulation (PWM) control approach and digital control approach for asymmetric DC-AC cascaded H-bridge multilevel inverter. The conventional available approach produces 2n+1 output level for n independent DC sources and the digital control approach produces 2n+1-1 output level for the same n independent DC sources with the same number switches. The proposed method also brings out the salient features of using Digital control over the conventional PWM control by producing a low total harmonic distortion level (THD) level while considering R-load. The simulation is done with the help of MATLAB and subsequently verified experimentally. © 2006-2015 Asian Research Publishing Network (ARPN).


Selvaraju P.,Vel Technology Multitech | Nirmala Gnanam Pricilla B.,St Anns College For Women
International Journal of Control Theory and Applications | Year: 2016

A cordial labeling as an application of communication network, in this paper we have given cordial labeling for the graph Cp•Cq t ∀ p, q and t, i.e., attaching the one vertex union of cycles Cq on each vertex of cycle Cp, and also shown that the cordial labeling for the quadrilateral snake graph QSn, ∀ n gluing with each vertex of graphs Cp • Cq t, i.e., QSn (Cp • Cq t ), ∀ n ≥0. Finally the domination number of this graph is analyzed. © International Science Press.


Mani P.K.,Vel Technology Multitech | Siddappa Naidu K.,Vel Technology Multitech
ARPN Journal of Engineering and Applied Sciences | Year: 2016

The main objective of this paper is to improve power quality in the facility side i.e. distribution side. For that we are implementing most recent FACTS device called Unified Power Quality Conditioner (UPQC). The unified power quality conditioner (UPQC) is a custom power device, which mitigates voltage and current-related PQ issues in the power distribution systems. The proposed topology helps to match the dc-link voltage requirement of the shunt and series active filters of the UPQC. The topology uses a capacitor in series with the interfacing inductor of the shunt active filter, and the system neutral is connected to the negative terminal of the dc-link voltage to avoid the requirement of the fourth leg in the voltage source inverter (VSI) of the shunt active filter. The average switching frequency of the switches in the VSI also reduces; consequently the switching losses in the inverters reduce. And also, the level of harmonics present in the distribution line gets reduced. © 2006-2016 Asian Research Publishing Network (ARPN).

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