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by
S. Jayalakshmi |
Total Records (
8 ) for
S. Jayalakshmi |
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R. Thavasi
,
S. Jayalakshmi
,
R. Radhakrishnan
and
T. Balasubramanian
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The present investigation is on evaluation of biodegradation potential of four species of hydrocarbonoclastic bacteria, B. megaterium, C. kutscheri, L. delbrueckii and P. aeruginosa and screening for plasmids. For biodegradation study, the strains were cultured in mineral salt medium with 0.1% of crude oil for seven days. Biodegradation results inferred that, P. aeruginosa showed 85.15% of crude oil degradation, followed by B. megaterium (78.5%), C. kutscheri (76.4%) and L. delbrueckii (71.6%). Strains were grown for 24 h in Luria-Bertani broth for plasmid study. Plasmid study revealed that, P. aeruginosa harbored two plasmids with molecular weight of 4.2 and 3.8 kb. The other strains namely L. delbrueckii, C. kutscheri and B. megaterium were found to have single plasmid with respective molecular weight of 3.8, 4.2 and 4.1 kb. Complete loss of biodegradation potential was observed when the plasmids of these strains cured with acridine orange. |
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S. Jayalakshmi
and
S.P. Rajagopalan
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In this research, a parallel implementation of a Modular Simulated Annealing (MSA) algorithm, applied to classical Job-Shop Scheduling (JSS) problems is presented. The implementation has been done as a multiple island system suitable to run on the Distributed Resource Machine (DRM) environment, which is a novel scalable, distributed virtual machine developed based on Java technology. The support of the DRM environment was very effective with respect to message passing, having collaboration with a remote machine. The empirical results show that the method proposed is quite successful compared to the ordinary MSA and other systems described in literature. |
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R. Radha
,
S. Jayalakshmi
and
S.P. Rajagopalan
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In this study we show that the gene-expression
profiles based on microarray analysis can be used to predict the genes
which are responsible for death of the patient in early-stage B-cell Lymphoma.
This study presents a new computational method for this prediction and
use an informative subset of samples to identify genes whose expression
is related to the problem under study. A reduction technique integrating
global normalization, fuzzy membership generation, Pearson`s correlation
method are used to identify genes which are related to non survival. The
early identification of the genes causing B-cell Lymphoma that leads to
death will benefit patients in the sense that the patients can be provided
proper therapy to increase their life span. The validity of the results
are established with the help of statistical methods. |
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R. Muralinaidu
,
S. Jayalakshmi
and
C.R. Ramachandran
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The patient suffering from oral cancer usually comes to the dental surgeon
when the lesion is in its advanced stages leading to poor treatment outcome
and prognosis. Hence early detection is the key to success. Autofluorescence
spectroscopy is a new non invasive real time technique which is explored
for the early detection of oral cancer. This study has been designed to
analyze the fluorescent property of tissue as it progresses from normal
to malignancy when it is excited at 405 nm of light. This study uses a
fiber optic-based fluorescence spectroscopy system to measure the autofluorescence
spectra of six each in normal control, premalignant and malignant group
of hamster`s buccal cheek pouch carcinogenesis model. The tissues were
excited at 405 nm and the emission scan was obtained over a range of wavelengths.
A prominent peak at 635 nm and a small peak at 700 nm in the malignant
tissues when excited at 405 nm was observed which was absent in the normal
and premalignant group. An addition small peak at 490 nm was observed
in all the three groups. Mean intensity ratio parameters I490/635,
I490/700 and I635/700 were introduced and found
that the difference between the groups and within the groups was statistically
significant. Further ratio parameters were able to differentiate between
the normal-malignant and premalignant-malignant group. The results obtained
indicate that this technique would help the surgeons to early diagnose
the lesion at the early stages. |
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N. Annamalai
,
R. Anburaj
,
S. Jayalakshmi
and
R. Thavasi
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In the present study water, ethanol, methanol, acetone, hexane and butanol extracts of two Bivalves, Perna viridis and Crassostrea madrasensis were screened for antibacterial activity. The extracts were obtained from whole body tissue of the animals and tested against 10 different pathogenic bacteria viz., Escherichia coli, Klebsiella oxytoca, K. pneumoniae, Lactobacillus vulgaris, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella typhi, S. paratyphi, Staphylococcus aureus and Vibrio sp. Ethanol extract of P. viridis showed maximum antibacterial activity against E. coli and S. aureus. Ethanol extract of C. madrasensis exhibited highest activity against S. aureus. Water extract of P. viridis and C. madrasensis showed highest activity against E. coli and P. mirabilis, respectively. The 10:10 (methanol: ethanol) fractionated extracts of P. viridis shows highest activity against P. mirabilis (8 mm), 14:6, 4:16 and 2:18 fractions showed prominent activity against P. aeruginosa, E.coli and K. pneumoniae. In C. madrasensis also 10:10 fraction showed highest activity E. coli, P. aeruginosa and S. aureus. The 18:2, 12:8 and 2:18 fractionated extracts of C. madrasensis exhibits effective activity against S. aureus, S. typhi and E. coli. Water, ethanol and methanol extracts showed antibacterial activity against all most all the bacteria tested. Compare to water extracts, ethanol and methanol extracts showed more activity against all pathogens. |
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Samanta Saha
,
R. Thavasi
and
S. Jayalakshmi
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This study deals with isolation and identification of Pseudomonas aeruginosa from marine environment for phenazine pigment production. Pigment production results revealed that, the strain could able to produce two different pigments namely, pyocyanin and pyorubrin. Maximum biomass was observed at 66 h of incubation, but the pigment production seems to be continuous throughout the culture period (72 h). Antibacterial activity of the pigments was evaluated against pathogenic bacteria, maximum growth inhibitory activity was observed with pyocyanin and pyorubrin at 20 μL concentration (1.7 and 1.3 cm, respectively) against Citrobacter sp. Hemolytic activity of the pigments inferred that, hemolysis was observed with both pigments at 15, 20 and 25 μL concentration and no hemolysis was found at 5, 10 and 15 μL. The pigments were evaluated for their potential as food colourants with agar. Pleasant colouration was observed with pyocyanin and pyorubrin at 25 mg mLG-1 concentration. |
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R. Muthezhilan
,
N. Yogananth
,
S. Vidhya
and
S. Jayalakshmi
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The present study deals with the distribution of fungal species in Cuddalore dye industrial waste (Lat 11°42`N; Long 79°46`E) and their dye degrading activity. Totally 13 species under 17 genera were isolated and screened for their decolorization activity against methylene blue, gentian violet, crystal violet, cotton blue, Sudan black, malachite green, methyl red and corbol fushion in mineral salt medium and Czepex-Dox broth. In agar medium, decolorization began with the formation of zone of clearance around the colonies. Aspergillus ochraceus, A. terreus, A. niger, Penicillium citrinum and Fusarium moniliforme decolorized maximum number of dyes to a great extent. Mucor racemosus, Cladosporium cladosporioides, Penicillium oxalicum and Trichoderma viride did not decolorize any of the dyes tested. In liquid medium, decolorizing activity was measured spectrophotometrically. Aspergillus ochraceus, A. terreus, A. niger, Penicillium citrinum and Fusarium moniliforme registered maximum color reduction, where as Mucor racemosus, Cladosporium cladosporioides, Penicillium oxalicum and Trichoderma viride expressed very low amount of color reduction. Biomass and the extent of dye removal are directly propositional. Among the 13 species of fungal isolates, Aspergillus ochraceus, A. terreus, A. niger, Fusarium moniliforme and Penicillium citrinum seems to be potential candidates for dye degradation. These strains can be used for the bioremediation of environs polluted with dye effluents. |
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V. Neelambari
,
V. Vasanthabharathi
,
R. Balasubramanian
and
S. Jayalakshmi
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A halotolerant strain of Aeromonas hydrophila was isolated from Vellar estuary, Parangipettai coast, Tamilnadu, India as a best enzyme producer using Tween 80 agar medium. Optimization studies revealed its maximum lipase production with optimized conditions such as 3% Tween80 as carbon source, 1% beef extract as nitrogen source, 0.3% fish waste as cheaper source, pH 9, temperature 37°C, 3% NaCl and 60 h incubation period. Optimized lipase partially purified with 60% Ammonium sulphate purification method results maximum enzyme production of 15 U/mL/L with 34 kDa molecular weight. The enzyme proved increased stability towards pH 7.5-9.5, 40-50°C and 15-30% of organic solvents for 1 h. The results concluded that the Aeromonas hydrophila is one of the potential alkaline lipase producing marine bacteria, with stability towards increased pH, temperature and organic solvents and preferable for further industrial applications. |
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