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Search Results: 1 - 10 of 2641 matches for " Ravi Kant "
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Effects of plant latex based anti-termite formulations on Indian white termite Odontotermes obesus (Isoptera: Odontotermitidae) in sub-tropical high infestation areas  [PDF]
Ravi Kant Upadhyay
Open Journal of Animal Sciences (OJAS) , 2013, DOI: 10.4236/ojas.2013.34042
Abstract: In the present investigation various bioassays were conducted to evaluate the anti-termite efficacy of plant latex based formulations to control population of Indian white termite in subtropical soil. Results reveal that crude latex, its fractions and combinatorial fractions have shown very high toxicity against O. obesus. The LD50 values for different latex fractions of 24 h were in a range of 5.0-17.613 μg/mg while combined mixtures of Calotropis procera have shown synergistic activity against termites and caused comparably high mortality with LD50 1.987-6.016 μg/mg. The mortality rate was found dose and time dependent as it was found to be increased with an increase in dose and exposure period. In olfactometry tests, C. procera latex solvent fractions have shown significant repellency at a very low dose 0.010-0.320 μg/mg. Interestingly, solvent fractions have significantly repelled large numbers of worker termites due to volatile action of active components of latex and different additives. ED50 values obtained in crude latex were 0.121 μg/mg body weights while combinatorial formulations have shown ED50 in between 0.015-0.036 μg/mg. Statistical analysis of repelled and un-repelled termites gave a low Chi-square value (X2
Antimicrobial Activity of Fruit Latexes from Ten Laticiferous Plants  [PDF]
Ravi Kant Upadhyay
American Journal of Plant Sciences (AJPS) , 2015, DOI: 10.4236/ajps.2015.63053
Abstract: In the present investigation antibacterial activity of latexes from ten Indian plant species Spondias dulcis (Amra), Diospyros melanoxylon (Tendu), Terminalia bellirica (Wahera), Ficus glomerata (Gular), Phyllanthus emblica (Awla), Thevetia nerifolia (Kaner), Carica papaya (Papita), Calotropis procera (Ak), Ficus benghalensis (Bargad), Atrocarpus heterophyllus (Kathal) collected from Go-rakhpur, North India were determined in various in vitro systems. MIC (minimum inhibitory concentration) and MBC (minimum bactericidal concentration) values were determined in growth inhibitory bioassays by using different increasing concentrations of various latex extracts. Latex samples were diluted by using serial micro dilution method up to 10-10 method with Luria broth culture medium. These values were obtained significantly 2 - 3 times lower than that of broad spectrum antibiotic drugs. Besides this, inhibition zone diameters were measured in agar disc diffusion assay. A known volume i.e. 0.1 - 20 μg/μl of each latex were coated on separate sterile filter paper discs (Whatman No. 1) measuring 6 mm in size. Latex fractions registered significantly higher growth inhibition than that of broad spectrum antimicrobial drugs. Present study indicates the potential use of shows that both latex and its components and latex as are valuable source of medicinal products/active principles that can be used for treatment of life threatening infectious diseases. Because of higher inhibitory and cidal potential obtained in latexes than the synthetic drugs these that could lead to become efficient phytomedicines mainly to have and develop as complete drug formulations against to control infectious microbes.
GC-MS Analysis and in Vitro Antimicrobial Susceptibility of Foeniculum vulgare Seed Essential Oil  [PDF]
Ravi Kant Upadhyay
American Journal of Plant Sciences (AJPS) , 2015, DOI: 10.4236/ajps.2015.67110
Abstract: Essential oil from seeds of Foeniculum vulgare was extracted on Clevenger apparatus. Essential oil was analyzed on Gas-Chromatography-Mass spectrometry (GC-MS) from which thirty six components were identified, among which 6 major and 30 minor components having different structural formulae and molecular weight representing total 99.98% of oil. Essential was investigated for its antibacterial and antifungal activity against seven infectious microbial pathogens. Paper disc diffusion and serial micro-dilution assays were performed for the determination of inhibition zone (DIZ) diameters and minimal inhibitory concentration, respectively. The Foeniculum vulgare essential oil showed the Diameter of Inhibition Zone (DIZ) ranging from 19.4 ± 0.07 - 26.4 ± 0.09 mm at a concentration level of 28 μg/disc in all the ten strains tested. The minimum inhibitory concentration (MIC) of essential oil against bacterial and fungal strains was obtained in the range of 7.0 - 56 μg/ml. Antibacterial and antifungal activity of Foeniculum vulgare essential oil is due to the presence of certain secondary plant metabolites such as terpenoids, steroids and flavonoids, esters and acids which are identified in the essential oil. The oil components can be further studied for their biological activity and overcome the problem of drug resistance in microbes.
Antimicrobial Activity of Purified Toxins from Crossopriza lyoni (Spider) against Certain Bacteria and Fungi  [PDF]
Ravi Kumar Gupta, Ravi Kant Upadhyay
Journal of Biosciences and Medicines (JBM) , 2016, DOI: 10.4236/jbm.2016.48001
Abstract: Toxins from spider venom Crossopriza lyoni were subjected to purify on a Sepharose CL-6B 200 column. These were investigated for its antibacterial and antifungal activity against 13 infectious microbial pathogenic strains. Antimicrobial susceptibility was determined by using paper disc diffusion and serial micro-dilution assays. Triton X-100 (0.1%) proved to be a good solubilizing agent for toxin/proteins. Higher protein solubilization was observed in the supernatant than in the residue, except TCA. The elution pattern of purified and homogenized sting glands displayed two major peaks at 280 nm. First one was eluted in fraction no. 43 - 51 while second one after fraction no. 61 - 90. From gel filtration chromatography total yield of protein obtained was 67.3%. From comparison of gel chromatographs eluted toxins peptide molecular weight was ranging from 6.2 - 64 kD. Toxin peptides have shown lower MIC values i.e. 7.5 - 15 μg/ml against K. pneumoniae, E. coli, L. acidophilus, B. cereus; against S. aureus and M. luteus that the broad spectrum antibiotics i.e. tetracycline and ampicillin. In tests, larger inhibition zone diameter was obtained in comparison to control. Diameter of inhibition zones obtained in spider toxins at a concentration range of 197.12 - 0.96 g/ml for E. coli was 17.86 ± 0.21, Bacillus cereus 19.13 ± 0.21, L. acidophilus 16.83 ± 0.25, Micrococcus luteus 18.46 ± 0.17, S. aeurus 16.23 ± 0.19, Klebsiella pneumoniae 21.83 ± 0.16, Salmonella typhi 16.16 ± 0.21, Vibrio cholera 18.66 ± 0.21, Pseudomonas aeruginosa 18.66 ± 0.21, Aspergillus niger 22.9 ± 0.24, Candida albicans 24.66 ± 0.28, Rhizopus stolonifer 21.1 ± 0.16. Spider toxins generate cytotoxic effect on bacterial cells that results in heavy cell death. No doubt spider toxins can be used as alternate of broad spectrum antibiotics.
Sweet proteins – Potential replacement for artificial low calorie sweeteners
Ravi Kant
Nutrition Journal , 2005, DOI: 10.1186/1475-2891-4-5
Abstract: The prevalence of obesity and diabetes has increased dramatically in recent years in the United States, with similar patterns seen in several other countries including India [1] as well. Diabetes mellitus is a chronic disease caused by inherited or acquired deficiency in production of insulin by the pancreas or by the ineffectiveness of the insulin produced [2]. Artificial sweeteners like Saccharin, Aspartame, Cyclamate and AcesulfameK are used world-wide as low calorie sweeteners by patients affected by diseases linked to the consumption of sugar, e.g. diabetes, hyperlipemia, caries, obesity etc. but they have side effects such as psychological problems, mental disorders, bladder cancer, heart failure and brain tumors [3-7]. Sweet proteins have the potential to replace these artificial sweeteners, by acting as natural, good, low calorie sweeteners, as we know that proteins do not trigger a demand for insulin in these patients whereas sucrose does.In humans, the sweet taste is mainly due to the recently discovered T1R2-T1R3 receptor [8-10], two of the three members of the T1R class [8-10] of taste-specific proteins hypothesized to function in combination as a heterodimer. The human T1R2-T1R3 receptor recognizes natural and synthetic sweetness and T1R1-T1R3 recognizes umami taste [11,12]. So far there are seven known sweet and taste-modifying proteins, namely Brazzein [13], Thaumatin [14], Monelin [15], Curculin [16], Mabinlin [17], Miraculin [18] and Pentadin [19]. Properties and characteristics of these proteins are illustrated in Table 1. The key residues on the protein surface responsible for biological activity have not yet been identified with certainty for any of these proteins [20]. Monellin was found to be 100000 times sweeter than sucrose on a molar basis [21], followed by Brazzein and Thaumatin which are 500 times [13] and 3000 times sweeter then sucrose [14] respectively (the latter two on a weight basis). All of these proteins have been isolated from pla
Ravi Kant
Academic Research International , 2011,
Abstract: Teacher is the main pillar of educational system. It is to him compulsory to have teaching aptitude and responsibility in his job. An attempt has made to determine the difference between teachingaptitude and responsibility feeling among secondary school teachers. A sample consisting of 100 secondary school teachers were chosen in this study. Sample was equally divided on sex and locale base. After statistical treatment it revealed that sex and locale has no significant effect on teaching aptitude and responsibility. However minute differences were found in some cases.
A Study of Creativity of Secondary School Children as a Correlate of Some Television Viewing Habits
Ravi Kant
International Journal of Modern Education and Computer Science , 2012,
Abstract: The present study was undertaken to study of creativity in relation to TV viewing habits of secondary school students. The sample consists of 400 secondary school students of Rampur city. Verbal test of creativity and TV viewing habits questionnaire were used for this investigation. The result of this study shows that on some behalf TV viewing is negatively related to creativity but overall TV viewing is positively related to creativity of secondary school students. Students viewed variety type program on TV however they were low achiever or high achiever gain knowledge and information through TV. In this study relationship between creativity and TV viewing was positive overall but non significant.
Antimicrobial Activity of Purified Toxins from Yellow Wasp Polistes flavus (Vespidae) against Certain Bacteria and Fungi  [PDF]
Krishna Kumar Prajapati, Ravi Kant Upadhyay
Journal of Biosciences and Medicines (JBM) , 2016, DOI: 10.4236/jbm.2016.47010
Abstract: Yellow Wasp Polistes flavus venom toxins were isolated and purified on a Sepharose CL-6B 200 column. Purified proteins were investigated for its antibacterial and antifungal activity against 13 infectious microbial pathogens. Paper disc diffusion and serial micro-dilution assays were performed for the determination of inhibition zone (DIZ) diameters and minimal inhibitory concentration, respectively. Triton X-100 (0.1%) proved to be a good solubilizing agent for toxin/proteins. Higher protein solubilization was observed in the supernatant than in the residue, except TCA (tri-chloroacetic acid). The elution pattern of purified and homogenized sting glands exhibited two major peaks at 280 nm in fraction No. 41 - 61 and 81 - 101. The total yield of protein was 69.21% and specific activity was determined in each fraction. Molecular weights in protein fractions were ranging from 6 - 70 kD. MIC (Minimum Inhibitory Concentration) values were 12.3 μg/ml against K. pneumonia 12.3 μg/ml against E. coli and L. acidophilus, 24.6 μg/ml against B. cereus; 49.24 μg/ml against S. aureus and M. luteus. By agar disc diffusion method, the diameter of inhibition zones in mm in presence of yellow wasp toxins is at a concentration range of 98.56 - 6.9 μg/ml E. coli 18.36 ± 0.14, Bacillus cereus 14.566 ± 0.21, L. acidophilus 18.10 ± 0.21, Micrococcus luteus 18.76 ± 0.19, S. aeurus 17.36 ± 0.43, Klebsiella pneuminiae 19.56 ± 0.21, Salmonella typhi 19.96 ± 0.31, Vibrio cholera 21.83 ± 0.22, Pseudomonas aeruginosa 22.90 ± 0.09, Aspergillus niger 21.66 ± 0.16, Candida albicans 23.33 ± 0.26, Rhizopus stolonifer 24.96 ± 0.16 respectively. The antibacterial and antifungal activity of venom toxin may be due to action on cell membrane, its destruction and cell lysis. The wasp toxins may be used as strong biological agents to control microbes.
Evolution of New Variants/Mutants of JE Virus, Its Effect on Neurovirulence, Antigenicity, Host Immune Responses and Disease Transmission in Endemic Areas
Ravi Kant Upadhyay
Journal of Viruses , 2014, DOI: 10.1155/2014/516904
Abstract: This paper highlights various reasons of evolution of new mutants/variants of JE virus and its effects on neurovirulence, antigenicity, host immune responses, and disease transmission in endemic areas. Virus is reorganizing its genome by making sequence alterations, single site mutations, cluster specific reversions, and amino acid substitutions in neutralizing antigenic sites mainly in N′ glycosylation sites and epitopic regions of S and E proteins. Virus is regularly changing gene order, gene density by making substitution point mutations in important structural genes which make virus envelope proteins. Further, JE virus acquiring new genetic variations and adaptabilities through genetic recombination of wild strains with vaccine strains and assimilating new lethal genes that lead to emergence of molecular variants/mutants. These newly emerged JE virus genotypes have attained the ability to escape the immune defense and show wider resistance against vaccines and therapeutic agents. Thus new strains did significant elevation in the level of neurovirulence, antigenicity and pathogenesis. It is causing very high mortalities in various infant groups and imposing lifelong irreversible disorders in survivors and showing a regular trend of emergence and reemergence in endemic areas. The present review article emphasizes methods to suppress virus replication, reversion of neurovirulence, attenuation and an utmost need of more potential vaccines against cross reactive heterologous genotypes of JE virus to control disease transmission and mortalities occurring in endemic areas. 1. Introduction Flavivirus, Japanese encephalitis (JE) virus, is the leading cause of acute viral encephalitis syndrome of central nervous system and mortalities of patients throughout Asia [1]. Though a large number of flaviviruses, such as Dengue virus and West Nile Virus Murray Valley encephalitis virus, are capable of giving rise to encephalitis, but, among all flaviviruses, JEV is proved highly dreadful because it severely invade many tissues and cells to establish an acute epidemic encephalitis syndrome in patients. Virus invasion generates severe inflammatory responses inside host, which later on spreads throughout the brain and results in necrosis of neurons and causes perivesicular cuffing, thrombosis, and variable degree of meningitis. Virus imposes very high neurovirulence and hemorrhage that give rise multiple disorders and lethality in various infant groups. Moreover, severity of infection with flaviviruses usually results into long lasting immunity and virus antigens boost
Japanese Encephalitis Virus Generated Neurovirulence, Antigenicity, and Host Immune Responses
Ravi Kant Upadhyay
ISRN Virology , 2013, DOI: 10.5402/2013/830396
Abstract: In response to a JE virus attack, infected body cells start secretion of different cytokines and activate innate immune response. Virus starts neuronal invasion by entering into nerve cells and inflecting the central nervous system. It avoids exposure of body’s natural immunity and generates neurotrophic effects. Virus causes acute susceptibility to CNS and establishes encephalitis syndrome that results in very high fatality in children. In survivors, JEV inhibits the growth and proliferation of NCPs and imposes permanent neuronal disorders like cognitive, motor, and behavioral impairments. However, body cells start TCR mediated interactions, to recognize viral antigens with class I MHC complex on specific target cells, and operate mass killing of virus infected cells by increased CTL activity. Thus, both cell mediated and antibody interactions plays a central role in protection against JEV. In the present review article virus generated neurovirulence, antigenicity, and host immune responses are described in detail. More emphasis is given on diagnosis, clinical care, and active immunization with well-designed potential antiflavivirus vaccines. Further, for achieving an elite success against JEV, global eradication strategies are to be needed for making vaccination program more responsible and effective in endemic areas. 1. Introduction 1.1. Japanese Encephalitis Virus Japanese encephalitis virus (JEV) is an enveloped positive single stranded RNA virus that belongs to genus Flavivirus in the family Flaviviridae. JE is one of the most important endemic diseases that exists in Eastern Asia and Southeastern Asia including India, Nepal, Japan, China, Korea, Thailand, Indonesia, Malaysia, Vietnam, Taiwan, and the Philippines. Recently disease has shown its presence in Continental Australia and New Zealand. JE is a major public health problem, which causes high morbidity and mortality in pediatric groups. It is caused by a dreadful mosquito-borne virus (arbovirus) which is transmitted to human by mosquito, that is, Culex tritaeniorhynchus and Culex vishnui throughout rural areas of Asia. The natural cycle of Japanese encephalitis (JE) virus in endemic areas involves presence of water birds and Culex mosquitoes, particularly Culex tritaeniorhynchus, with pigs being also involved as an amplifying host and providing a link to humans through their proximity to housing. These play important role in amplification, dispersal, and epidemiology of JEV [1]. Transmission of JEV is seasonal, which increases with the increase in number of culicine mosquitoes after more
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