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31.
Annadurai Senthilkumar Krishnan Kannathasan Venugopalan Venkatesalu 《World journal of microbiology & biotechnology》2009,25(7):1297-1300
The antibacterial activity of the leaf essential oil of Blumea mollis was assayed against 14 clinically isolated bacterial strains on Muller–Hinton Agar medium and Muller–Hinton Agar medium with
5% sheep blood. The essential oil had promising antibacterial activity against all the bacterial strains tested. The highest
mean zone of inhibition and lowest values of minimum inhibitory concentration were recorded against methicillin-resistant
Staphylococcus aureus followed by beta hemolytic Streptococcus pyogenes. The Gram-positive bacteria were more sensitive than Gram-negative bacteria. Among the bacterial strains tested, Psudomonas aeruginosa was resistant to the essential oil. The results of the present study suggest that the essential oil of B. mollis is one of the new medicinal resources as an antibacterial agent against the bacterial strains tested. 相似文献
32.
Dharmarajan Sriram Perumal Yogeeswari Prathiba Dhakla Palaniappan Senthilkumar Debjani Banerjee Thimmappa H. Manjashetty 《Bioorganic & medicinal chemistry letters》2009,19(4):1152-1154
Eighteen 5-nitrofuran-2-yl derivatives were prepared by reacting 5-nitro-2-furfural with various (sub)phenyl/pyridyl thiosemicarbazide using microwave irradiation. The compounds were tested for their in vitro activity against tubercular and various non-tubercular mycobacterium species in log-phase and 6-week-starved cultures. Compound N-(3,5-dibromopyridin-2-yl)-2-((5-nitrofuran-2-yl)methylene)hydrazinecarbothioamide (4r) was found to be the most potent compound (MIC: 0.22 μM) and was 3 times more active than standard isoniazid (INH) and equally active as rifampicin (RIF) in log-phase culture of Mycobacterium tuberculosis H37Rv. In starved M. tuberculosis H37Rv, 4r inhibited with MIC of 13.9 μM and was found to be 50 times more active than INH and slightly more active than RIF. 相似文献
33.
V. Govindasamy M. Senthilkumar V. Mageshwaran K. Annapurna 《Journal of plant biochemistry and biotechnology.》2009,18(1):71-76
The enzyme 1-aminocyclopropane-1-carboxylate deaminase converts ACC, the precursor of the plant hormone ethylene to α-ketobutyrate and ammonium. The enzyme has been identified in few soil bacteria, and is proposed to play a key role in plant growth promotion. In this study, the isolates of plant growth promoting rhizobacteria were screened for ACC deaminase activity based on their ability to grow on ACC as a sole nitrogen source. The selected isolates showed the presence of other plant growth promoting characteristics such as IAA production, phosphate solubilization and siderophore production. The role of ACC deaminase in lowering ethylene production under cadmium stress condition was also studied by measuring in vitro ethylene evolution by wheat seedlings treated with ACC deaminase positive isolates. Nucleic acid hybridization confirmed the presence of ACC deaminase gene (acdS) in the bacterial isolates. 相似文献
34.
Energy dynamics in the C4 species dominated montane subtropical grassland at Nilgiri Biosphere Reserve, the Western Ghats, India 下载免费PDF全文
The energy dynamics in Thiashola grassland, a montane subtropical vegetation in Nilgiri Biosphere Reserve, the Western Ghats, India is studied for a period of one year. The study revealed that the energy content in unit biomass of C3 and C4 species has not varied significantly. However, the C4 species in total due to higher net primary production, entrapped 8.5 times greater solar energy (28.82 kcal/m2/day) than that of their C3 counterparts. Of the total energy fixed, the C3 and C4 species, respectively channeled 4.07 kcal/m2/day and 13.3 kcal/m2/day to the aboveground standing live compartment. The transfer rate of energy to standing dead compartment from standing live part were 3.22 kcal/m2/day and 10.36 kcal/m2/day for C3 and C4 species, respectively and both the C3 and C4 together transferred 4.81 kcal/m2/day of energy from standing dead to litter compartment. The total dissipation of energy from the system is determined to be 4401.11 kcal/m2/yr and the surplus quantity of 38.37% of energy is accumulated in the aboveground parts of both C3 and C4 species which indicates the availability of substantial amount of energetic fodder to the wild herbivores in the Thiashola grassland. 相似文献
35.
Pandian SR Deepak V Kalishwaralal K Gurunathan S 《Enzyme and microbial technology》2011,48(4-5):319-325
Here an attempt was made to biologically synthesize fluorescent cadmium sulfide nanoparticles and to immobilize the synthesized nanoparticles in PHB nanoparticles. The present study uses Brevibacterium casei SRKP2 as a potential producer for the green synthesis of CdS nanoparticles. Biologically synthesized nanoparticles were characterized and confirmed using electron microscopy and XRD. The size distribution of the nanoparticles was found to be 10-30 nm followed by which the consequence of time, growth of the organism, pH, concentration of CdCl(2) and Na(2)S on the synthesis of nanoparticles were checked. Enhanced synthesis and fluorescence emission of CdS nanoparticles were achieved at pH 9. The synthesized CdS NPs were immobilized with PHB and were characterized. The fluorescent intensity of the CdS nanoparticles remained unaffected even after immobilization within PHB nanoparticles. 相似文献
36.
Kabir ME Krishnaswamy S Miyamoto M Furuichi Y Komiyama T 《Applied microbiology and biotechnology》2011,90(2):553-564
Phage-display and competitive panning elution leads to the identification of minimum-sized antigen binders together with conventional
antibodies from a mouse cDNA library constructed from HM-1 killer toxin neutralizing monoclonal antibody (nmAb-KT). Antigen-specific
altered camelid-like single-domain heavy chain antibody (scFv K2) and a conventional antibody (scFv K1) have been isolated
against the idiotypic antigen nmAb-KT. The objectives of the study were to examine (1) their properties as compared to conventional
antibodies and also (2) their antifungal activity against different pathogenic and non-pathogenic fungal species. The alternative
small antigen-binder, i.e., the single-domain heavy chain antibody, was originated from a conventional mouse scFv phage library
through somatic hyper-mutation while selection against antigen. This single-domain antibody fragment was well expressed in
bacteria and specifically bound with the idiotypic antigen nmAb-KT and had a high stability and solubility. Experimental data
showed that the binding affinity for this single-domain antibody was 272-fold higher (K
d = 1.07 × 10−10 M) and antifungal activity was three- to fivefold more efficient (IC50 = 0.46 × 10−6 to 1.17 × 10−6 M) than that for the conventional antibody (K
d = 2.91 × 10−8 M and IC50 = 2.14 × 10−6 to 3.78 × 10−6 M). The derived single-domain antibody might be an ideal scaffold for anti-idiotypic antibody therapy and the development
of smaller peptides or peptide mimetic drugs due to their less complex antigen-binding site. We expect that such single-domain
synthetic antibodies will find their way into a number of biotechnological or medical applications. 相似文献
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38.
Saurav Prasad Katla Srikanth Anil M. Limaye Senthilkumar Sivaprakasam 《Biotechnology letters》2014,36(6):1303-1307
Casein whey permeate (CWP), a lactose-enriched dairy waste effluent, is a viable feed stock for the production of value-added products. Two lactic acid bacteria were cultivated in a synthetic casein whey permeate medium with or without pH control. Lactobacillus lactis ATCC 4797 produced d-lactic acid (DLA) at 12.5 g l?1 in a bioreactor. The values of Leudking–Piret model parameters suggested that lactate was a growth-associated product. Batch fermentation was also performed employing CWP (35 g lactose l?1) with casein hydrolysate as a nitrogen supplement in a bioreactor. After 40 h, L. lactis produced 24.3 g lactic acid l?1 with an optical purity >98 %. Thus CWP may be regarded as a potential feed-stock for DLA production. 相似文献
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40.
Senthilkumar Muthusamy Angelica M. DeMartino Lewis J. Watson Kenneth R. Brittian Ayesha Zafir Sujith Dassanayaka Kyung U. Hong Steven P. Jones 《The Journal of biological chemistry》2014,289(43):29665-29676
Derangements in metabolism and related signaling pathways characterize the failing heart. One such signal, O-linked β-N-acetylglucosamine (O-GlcNAc), is an essential post-translational modification regulated by two enzymes, O-GlcNAc transferase and O-GlcNAcase (OGA), which modulate the function of many nuclear and cytoplasmic proteins. We recently reported reduced OGA expression in the failing heart, which is consistent with the pro-adaptive role of increased O-GlcNAcylation during heart failure; however, molecular mechanisms regulating these enzymes during heart failure remain unknown. Using miRNA microarray analysis, we observed acute and chronic changes in expression of several miRNAs. Here, we focused on miR-539 because it was predicted to target OGA mRNA. Indeed, co-transfection of the OGA-3′UTR containing reporter plasmid and miR-539 overexpression plasmid significantly reduced reporter activity. Overexpression of miR-539 in neonatal rat cardiomyocytes significantly suppressed OGA expression and consequently increased O-GlcNAcylation; conversely, the miR-539 inhibitor rescued OGA protein expression and restored O-GlcNAcylation. In conclusion, this work identifies the first target of miR-539 in the heart and the first miRNA that regulates OGA. Manipulation of miR-539 may represent a novel therapeutic target in the treatment of heart failure and other metabolic diseases. 相似文献