Activity Guided Isolation of Antioxidant Tannoid Principles from Anogeissus latifolia

Raghavan Govindarajan1*,Madhavan Vijayakumar1,,Annie Shirwaikar2,,Ajay Kumar Singh Rawat1,,Shanta Mehrotra1,,Palpu Pushpangadan1 한국생약학회 2005 Natural Product Sciences Vol.11 No.3

Oxidative stress is an important causative factor in several human chronic diseases, such asatherosclerosis, cardiovascular disorders, mutagenesis, cancer, several neurodegenerative disorders, and the agingprocess. Phenolics and tannins are reported to be good antioxidants. Anogeissus latifolia (Combretaceae) bark hasnot available till date. Hence the present study was undertaken to isolate antioxidant compounds by activity-guided isolation. Inhibtion of diphenyl picryl hydrazyl (DPH) and Xanthine oxidase along with photoc-hemiluminescence assay were used as bioassay for antioxidant activity. Activity guided isolation was carried outusing silica column and the compounds were quantified using HPLC. Ethyl acetate and butanol fraction exhibitedpotent antioxidant activity. Bioassay-guided isolation led to isolation of ellagic acid (1) and dimethyl ellagic acid(2these three major tannoid principles present in A. latifolia, are responsible for the antioxidant potential andpossibly their therapeutic potential.

In vitro Antioxidant Activity of Ethanolic Extract of Chlorophytum borivilianum

R. Govindarajan1,,N. Sreevidya1,,M. Vijayakumar1,,M. Thakur2,,V.K. Dixit2,,S. Mehrotra*1,,P. Pushpangadan1 한국생약학회 2005 Natural Product Sciences Vol.11 No.3

Chlorophytum borivilianum Baker (Antharicaceae) comonly referred as ‘Safed Musli’ has beenwidely used in the Indian traditional systems of medicine to treat various diseases like rheumatism apart fromaphordisiac properties. C. borivilianum was screened for the first time to determine its antioxidant activity,isolation of the sapogenins and standardization of the isolated sapogenin fraction using HPTLC. Potent antioxidantactivity of ethanolic extract was found by their ability to scavenge DPPH (84.51%), hydroxyl radical (48.95 %),feryl bi-pyridyl complex (84.53%) along with the inhibition of lipid peroxidation (67.17%) at 100g/mlconcentration. The ethanolic extract also exhibited significant inhibition of superoxide anion radical generated byplant in the traditional system especially its use as a Rasayana drug.

Recent Advances in Polybenzimidazole (PBI)-based Polymer Electrolyte Membranes for High Temperature Fuel Cell Applications

Vijayakumar, Vijayalekshmi,Kim, Kihyun,Nam, Sang Yong The Korean Society of Industrial and Engineering C 2019 공업화학 Vol.30 No.6

Polybenzimidazole (PBI), an engineering polymer with well-known excellent thermal, chemical and mechanical stabilities has been recognized as an alternative to high temperature polymer electrolyte membranes (HT-PEMs). This review focuses on recent advances made on the development of PBI-based HT-PEMs for fuel cell applications. PBI-based membranes discussed were prepared by various strategies such as structural modification, cross-linking, blending and organic-inorganic composites. In addition, intriguing properties of the PBI-based membranes as well as their fuel cell performances were highligted.

Development of Tungsten Trioxide Using Pulse and Continuous Electrodeposition and Its Properties in Electrochromic Devices

Vijayakumar, Elayappan,Yun, Yong-Han,Quy, Vu Hong Vinh,Lee, Young-Hoon,Kang, Soon-Hyung,Ahn, Kwang-Soon,Lee, Seung Woo Electrochemical Society 2019 Journal of the Electrochemical Society Vol.166 No.4

<P>To develop an economical, efficient, and highly stable electrode having high transmittance modulation, thin films of tungsten trioxide (WO<SUB>3</SUB>) were deposited on an Indium-doped tin oxide (ITO) glass substrate by using simple one-step pulse voltage electrodeposition (PVE) and continuous voltage electrodeposition (CVE) routes. Electrochemical and optical analyses demonstrated that the WO<SUB>3</SUB> electrode prepared by PVE possessed high switching speed, high coloration efficiency, and excellent cyclic stability. Moreover, its stable performance in the colored state extended for a long duration even after the voltage was cutoff. The coloration efficiency values were determined to be 69.00 and 43.00 cm<SUP>2</SUP>/C for W-PVE-600s and W-CVE-200s, respectively. The excellent electrochemical and electrochromic properties were mainly attributed to large surface area of W-PVE-600s, which facilitated charge transfer and promoted insertion/exertion of H<SUP>+</SUP> ions in electrolytes better than the WO<SUB>3</SUB> electrode prepared by conventional methods. The significant electrocatalytic activity and stable performance have proved that the proposed W-PVE-600s film can be an alternative to conventional electrodes used in smart window technology applications.</P>

A Palm Vein Recognition System based on a Support Vector Machine

Vijayakumar Ponnusamy,Abhijit Sridhar,Arun Baalaaji,M. Sangeetha 대한전자공학회 2019 IEIE Transactions on Smart Processing & Computing Vol.8 No.1

Palm vein authentication is among the recent research in the field of access control applications. Because palm veins are tough to forge, they act as a reliable metric in security applications. Accurate extraction of palm veins is challenging in the presence of various dynamics, such as variant light conditions, variations in palm vein patterns from person to person, the cleanliness of the hand, etc. This paper presents a robust recognition process that makes use of a ridge filter for vein pattern extraction, and local binary patterns (LBP) for feature extraction. The ridge filter takes the major eigenvalue of the Hessian matrix, which contains the second-order derivative of the image pixels. The eigenvalue is then processed using LBP feature extraction from the vein patterns. Finally, a support vector machine is used for classification of subsequent images. The result shows that the system can provide accuracy of 89%, with a computation time of 0.423s. The false acceptance rate and false rejection rate were also evaluated as benchmark parameters, which show significantly good performance.

Intractable anal pain in B-cell acute lymphocytic leukemia patients: treatment options

Vijayakumar, Vissnukumar,Agarwal, Anil,Shamshery, Chetna,Gautam, Sujeet The Korean Pain Society 2019 The Korean Journal of Pain Vol.32 No.1

Glutathione Transferases Superfamily: Cold-Inducible Expression of Distinct <i>GST</i> Genes in <i>Brassica oleracea</i>

Vijayakumar, Harshavardhanan,Thamilarasan, Senthil Kumar,Shanmugam, Ashokraj,Natarajan, Sathishkumar,Jung, Hee-Jeong,Park, Jong-In,Kim, HyeRan,Chung, Mi-Young,Nou, Ill-Sup MDPI 2016 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.17 No.8

<P>Plants, as sessile organisms, can suffer serious growth and developmental consequences under cold stress conditions. Glutathione transferases (GSTs, EC 2.5.1.18) are ubiquitous and multifunctional conjugating proteins, which play a major role in stress responses by preventing oxidative damage by reactive oxygen species (ROS). Currently, understanding of their function(s) during different biochemical and signaling pathways under cold stress condition remain unclear. In this study, using combined computational strategy, we identified 65 <I>Brassica oleracea</I> glutathione transferases (<I>BoGST</I>) and characterized them based on evolutionary analysis into 11 classes. Inter-species and intra-species duplication was evident between <I>BoGST</I>s and <I>Arabidopsis</I> GSTs. Based on localization analyses, we propose possible pathways in which <I>GST</I> genes are involved during cold stress. Further, expression analysis of the predicted putative functions for <I>GST</I> genes were investigated in two cold contrasting genotypes (cold tolerance and susceptible) under cold condition, most of these genes were highly expressed at 6 h and 1 h in the cold tolerant (CT) and cold susceptible (CS) lines, respectively. Overall, <I>BoGSTU19</I>, <I>BoGSTU24</I>, <I>BoGSTF10</I> are candidate genes highly expressed in <I>B. oleracea</I>. Further investigation of GST superfamily in <I>B. oleracea</I> will aid in understanding complex mechanism underlying cold tolerance in plants.</P>

CuCo₂O₄ flowers/Ni-foam architecture as a battery type positive electrode for high performance hybrid supercapacitor applications

Vijayakumar, Subbukalai,Nagamuthu, Sadayappan,Ryu, Kwang-Sun Elsevier 2017 ELECTROCHIMICA ACTA Vol.238 No.-

<P><B>Abstract</B></P> <P>The battery type CuCo<SUB>2</SUB>O<SUB>4</SUB> electrode was evaluated as a positive electrode material for its hybrid supercapacitor applications. CuCo<SUB>2</SUB>O<SUB>4</SUB> flowers were prepared on Ni-foam through a simple hydrothermal process and post calcination treatment. The structure and morphology of the CuCo<SUB>2</SUB>O<SUB>4</SUB> flowers/Ni-foam was characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy. FESEM clearly revealed the flower-like morphology, which was composed of large number of petals. The length and width of the petals ranged from approximately 5–8μm and approximately 50–150nm, respectively. The CuCo<SUB>2</SUB>O<SUB>4</SUB> flowers/Ni-foam electrode was employed for electrochemical characterization for hybrid supercapacitor applications. The specific capacity of the CuCo<SUB>2</SUB>O<SUB>4</SUB> flower-like electrode was 692.4Cg<SUP>−1</SUP> (192.3mAhg<SUP>−1</SUP>) at a scan rate of 5mVs<SUP>−1</SUP>. The flower-like CuCo<SUB>2</SUB>O<SUB>4</SUB> electrode exhibited a maximum specific capacity of 645.1Cg<SUP>−1</SUP> (179.2mAhg<SUP>−1</SUP>) at a specific current of 1Ag<SUP>−1</SUP> and good long term cyclic stability. The high specific capacity, good cyclic stability, and low internal and charge transfer resistance of the CuCo<SUB>2</SUB>O<SUB>4</SUB> flowers/Ni-foam electrode confirmed the suitability of the prepared material as a positive electrode for hybrid supercapacitor applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> This paper reports the hydrothermal preparation of CuCo<SUB>2</SUB>O<SUB>4</SUB> flowers on Ni-foam. </LI> <LI> The CuCo<SUB>2</SUB>O<SUB>4</SUB> flowers exhibits maximum specific capacity of 645.1Cg<SUP>−1</SUP>. </LI> <LI> After 2000 cycles, 109% of the initial specific capacity was retained. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>The Ni- foam supported CuCo<SUB>2</SUB>O<SUB>4</SUB> flowers exhibits a high specific capacity with superior long term cyclic stability.</P> <P>[DISPLAY OMISSION]</P>

<i>In-vitro</i> assessment of the probiotic potential of <i>Lactobacillus plantarum</i> KCC-24 isolated from Italian rye-grass (<i>Lolium multiflorum</i>) forage

Vijayakumar, Mayakrishnan,Ilavenil, Soundharrajan,Kim, Da Hye,Arasu, Mariadhas Valan,Priya, Kannappan,Choi, Ki Choon Elsevier 2015 Anaerobe Vol.32 No.-

<P><B>Abstract</B></P> <P>The aim of the present study was to determine the probiotic potential of the lactic acid bacteria <I>Lactobacillus plantarum</I> KCC-24 (<I>L. plantarum</I> KCC-24), that was isolated and characterized from Italian ryegrass (<I>Lolium multiflorum</I>) forage. The following experiments were performed to assess the probiotic characteristics such as antifungal activity, antibiotic susceptibility, resistance to low pH, stimulated gastric juice and bile salts, proteolytic activity, auto-aggregation, cell surface hydrophobicity, and <I>in vitro</I> antioxidant property. The isolated <I>L. plantarum</I> KCC-24 exhibited significant antifungal activity against the various fungal strains of <I>Aspergillus fumigatus</I> (73.43%), <I>Penicillium chrysogenum</I> (59.04%), <I>Penicillium roqueforti</I> (56.67%), <I>Botrytis elliptica</I> (40.23%), <I>Fusarium oxysporum</I> (52.47%) and it was susceptible to numerous antibiotics, survived in low pH, was resistant to stimulated gastric juices and bile salts (0.3% w/v). Moreover, <I>L. plantarum</I> KCC-24 exhibited good proteolytic activity. In addition <I>L. plantarum</I> KCC-24 showed potent antioxidant and hydrogen peroxide resistant property. In conclusion, the isolated <I>L. plantarum</I> KCC-24 exhibited several characteristics to prove it's excellent as a potential probiotic candidate for developing quality food for ruminant animals and human.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Lactic acid bacteria have been used in food industries for food preservation. </LI> <LI> Potential probiotic of LAB isolated from Italian Rye-grass forage. </LI> <LI> KCC-24 revealed good antifungal activity against various fungal genera. </LI> <LI> Isolated lactic acid bacteria KCC-24 showed significant probiotic properties. </LI> <LI> <I>L. plantarum</I> KCC-24 showed the good free radical scavenging activity. </LI> </UL> </P>

In Vitro Biocidal Actions of <i>Rhus verniciflua</i> Bark Extract Wrapped Gold Nanoballs Against Biofilm-Forming Food-Borne Bacterial Pathogens

Vijayakumar, Sekar,Saravanakumar, Kandasamy,Hu, Xiaowen,Wang, Myeong-Hyeon Plenum Press 2019 Journal of cluster science Vol.30 No.6

<P> The research for innovative antibiofilm drugs is essential due to the increased microbial resistance to antibiotics presently in use. Now a day’s natural products wrapped nano biomaterial play an important role in the field of medicine. The aqueous bark extracts of <I>Rhus verniciflua</I> was used to synthesize gold nanoparticles (Rh-AuNPs) by green method. The synthesized nanoparticles were characterized (optical property, crystallinity, functional groups, size, shape and purity) by UV-vis spectroscopy (UV), X-ray diffraction (XRD), Fourier transform infrared (FTIR), Field emission transmission electron microscopy (FE-TEM) with Energy dispersive X-ray (EDX). An effective antioxidant activity was observed at 100 μg/ml of Rh AuNPs. The acridine orange, live and dead (PI-SYTO-9) staining assay using confocal laser scanning microscopic, results evidanced that the Rh-AuNPs (100 μg/ml) was effectively inhibited the biofilms of <I>Escherichia coli</I> and <I>Staphylococcus aureus.</I> In addition, Rh-AuNPs also significantly inhibited the cell surface hydrophobicity of both <I>E. coli</I> and <I>S. aureus</I> at 100 μg/ml. This study reports antibacterial potency of Rh-AuNPs and that have significant therapeutic properties. </P>