Dr.S Ravikumar - Academia.edu (original) (raw)

Papers by Dr.S Ravikumar

International Journal of Drug Delivery, 2010

Background: Dietary phytohormones may influence the metabolic processes in animal cells. To deter... more Background: Dietary phytohormones may influence the metabolic processes in animal cells. To determine the effect of the plant growth regulators 28homobrassinolide, gibberellic acid and kinetin on the tissue hexokinase and some blood components in male rats. Methods: 50µg 28-bomobrassinolide, gibberellic acid and kinetin (Normal saline served as control) was injected intradermally. Hexokinase activity in several tissues and blood level of glucose, hemoglobin and cholesterol were determined 2 h after injection. Findings: 28-homobrassinolide increased hexokinase activity in all tissues studied, and reduced blood glucose level but increased hemoglobin and cholesterol level. Gibberellic acid increased hexokinase activity in liver, but decreased it in other tissues and increased significantly blood cholesterol and slightly glucose and hemoglobin levels. Kinetin decreased hexokinase activity significantly in liver and kidney, but not significantly in other tissues, and reduced slightly glucose and hemoglobin levels and reduced significantly serum cholesterol level. Conclusion: This study indicated that treatment of rat with 28-homobrassinolide significantly increased hexokinase activity in liver, heart and kidney whereas gibberellic acid increased hexokinase activity only in the liver, and Kinetin decreased hexokinase activity in most tissues. Decreased hexokinase activity was observed due to kinetin and gibberellic acid treatment, except for gibberellic acid in the liver tissue, and was indicative of the fact that kinetin and gibberellic acid acted as negative modulators of this enzyme in the rat tissues. Thus, three different phytohormones possessed different degrees of effect in the animal cells.

International Journal of Biological and Chemical Sciences, 2010

The in vitro antibacterial activity of column chromatographic fractions of n-hexane, benzene, chl... more The in vitro antibacterial activity of column chromatographic fractions of n-hexane, benzene, chloroform, acetone, ethanol and water extracts of Excoecaria agallocha L. were determined against 24 localized and common bacterial pathogens. Antibacterial assay was performed by agar diffusion method against 4 specialized urinary tract pathogens, 10 antibiotic sensitive ophthalmic bacterial pathogens, 5 antibiotic resistant bacterial pathogens and 5 fish pathogens. It was found that the 11 th fraction of chloroform extract and the 30 th fraction of water extract exhibited broad spectrum of antibacterial activity. These 2 active fractions were further investigated through UV-Visible, NMR and FT-IR and were characterized as benzoate and diterpenes and their derivatives viz., 2,3-secoatisane type diterpene and 3,4,5-trihydroxy methyl benzoate.

Biomedicine & Pharmacotherapy, 2010

The Publisher regrets that this article is an accidental duplication of an article that has alrea... more The Publisher regrets that this article is an accidental duplication of an article that has already been published, http://dx.doi.org/10.1016/j.bionut.2010.09.001. The duplicate article has therefore been withdrawn.

International Journal of Medicine and Medical Sciences, May 30, 2009

Forty-five crude methanolic extracts from 23 marine halophytes were screened against five bacteri... more Forty-five crude methanolic extracts from 23 marine halophytes were screened against five bacterial and two fungal saprophytic pathogens of diseased silkworm Bombyx mori. Among thirty-four mangrove samples screened for antibacterial activity, the leaf extract of Rhizophora mucronata showed maximum inhibitory activity against Staphylococcus aureus (20 mm dia.). The seaweed species of Padina tetrostomatica showed maximum inhibitory activity against Proteus vulgaris (11 mm dia) and the seagrass species of Syringodium isoetifolium showed maximum inhibition against P. vulgaris (9 mm dia). The solar saltern cyanobacterium Phormidium fragile exhibits higher inhibitory activity against P. vulgaris (17 mm dia). The growth of fungal pathogens of Aspergillus niger was highly inhibited by S. isoetifolium (15 mm dia) and Padina tetrostomatica (13 mm dia) respectively compared with the other extracts. It is also noted that 16x concentration of the leaf extract of R. mucronata and S. isoetifolium showed complete reduction in the bacterial and fungal viable counts within 3 h of exposure.

International Journal of Current Research in Biosciences and Plant Biology, 2016

Medicinal plants have a long history of use and their use is widespread in both developing and de... more Medicinal plants have a long history of use and their use is widespread in both developing and developed countries. From the last few decades, there is an increasing interest in formation of the drugs derived from plants which helps to control diseases. Also the herbal products are safer than synthetic products which may be harmful and unsafe to the human and environment. The present study made an attempt to find out the antidiabetic property of Costus species. Fresh elder leaves of species viz., Costus pictus and Costus speciosus were collected from Western Ghats, Tamil Nadu. The plant samples were washed thoroughly and extracted in ethanolic solvent. In in vitro αamylase inhibitory study, the maximum inhibition of Costus pictus was of 88.75% at a concentration 400µg.ml-1. In starch iodine color assay, the maximum inhibition of color change of extract at 400µg.ml-1. Glucose uptake inhibition assay data suggests Costus species is significant in inhibiting glucose diffusion. It is concluded from the present study that the Costus species extracts potentiate the antidiabetic activity and can be used as an alternate for the treatment of diabetes after completing successful clinical trials.

Journal of environmental biology / Academy of Environmental Biology, India, 2009

Anti-inflammatory drugs presently available for the treatment of various inflammatory disorders h... more Anti-inflammatory drugs presently available for the treatment of various inflammatory disorders have diverse and undesirable side effects. In recent years; active principles of varied chemical structures have been isolated from plants possessing anti-inflammatory activity. Sulfated polysaccharides present in algae were shown to posses anti-inflammatory properties. Ulva lactuca the green alga available in Tuticorin coast was found to show anti-inflammatory effect as evidenced by the reduction in the inhibition of oedema at the 4th day of the experiment compared with the positive control drug and control. Microscopic examination of the elite organs did not show any alteration compared with the control and reference group. Moreover the hematological parameters were found normal compared with the control. The present study suggests the need for further studies for the development of anti-inflammatory drug of marine origin with proper clinical trials.

World Applied Sciences …, 2011

Asian Pacific journal of tropical medicine, 2011

To identify the in vitro antiplasmodial activity of seaweed plants against Plasmodium falciparums... more To identify the in vitro antiplasmodial activity of seaweed plants against Plasmodium falciparumstrains. A total of eight seaweeds were collected from Kanyakumari district, Tamilnadu, India. The in vitro antiplasmodial activity was performed in 96 well plates against Plasmodium falciparum, and preliminary phytochemcial analysis were performed for the extracts. Of the selected plants Enteromorpha intestinalis (2.61%) showed maximum percentage of extraction. The minimum concentration of inhibitory (IC50) value was observed with Chaetomorpha antennina [(26.37±4.14) μg/mL] further, the positive controls such as chloroquine and artemether showed antiplasmodial activities (IC50) with (19.10±5.93) and (6.03±0.21) μg/mL concentrations, respectively. The preliminary phytochemical analysis of the seaweed extracts showed a variety of phytochemical constituents such as carboxylic acids, phenols, protein, resins, steroids and sugars. The antiplasmodial activity of the seaweed extract might due t...

International Journal of Medicine and Medical Sciences, 2013

The objective of the study was to evaluate the antibacterial activities of N,N’[1,1’-dithiobis(ph... more The objective of the study was to evaluate the antibacterial activities of N,N’[1,1’-dithiobis(phenylene)]bis(benzyldeneimine), referred to as L1 and o,o’-(N,N-dipicolinyldene) diazadiphenyldisulfide, referred to as L2, containing disulfide moieties against some ophthalmic pathogens (Klebsiella species, Escherichia coli, Streptococcus species, Proteus morganii, Pseudomonas species, Streptococcus pneumoniae, Acinetobacter species, Streptococcus pyogenes and Streptococcus viridans), urinary tract infectious pathogens (P. morganii, E. coli, Pseudomonas spp., Enterobacter species, and Klebsiella spp.) and antibiotic resistant pathogens (Staphylococcus species, Streptococcus, Pseudomonas spp., and Klebsiella spp.) for minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The MIC for the ophthalmic pathogens and antibiotic resistant pathogens were found to be 400 to 500 µg/ml, while for the urinary tract infectious pathogens a lower MIC value (200 µg/ml) was...

Journal of environmental biology / Academy of Environmental Biology, India, 2010

Study of marine organisms for their bioactive potential, being an important part of marine ecosys... more Study of marine organisms for their bioactive potential, being an important part of marine ecosystem, has picked up the rhythm in recent years with the growing recognition of their importance in human life. Investigation was carried out to isolate 32 strains of endo and epiphytic bacteria in 2 seagrass species viz., Syringodium isoetifolium and Cymodocea serrulata. Morphologically different bacterial strains were tested against 5 antibiotic resistant human bacterial pathogens, of which 10 associated bacteria shown inhibitory activity against one or more bacterial pathogens. Minimum inhibitory concentration (MIC) and Minimum bacterial concentration (MBC) determination with extracellular bioactive compounds from the associated bacteria reveals that, the strain ENC 5 showed inhibitory activity against all the bacterial pathogens with the maximum sensitivity against Pseudomonas aeruginosa at the MIC value of 500 microg ml(-1).

International Journal of Pharmaceutics, 2012

Sulfated ␤-cyclodextrin was synthesized from sulfonation of ␤-cyclodextrin and sulfated polymer w... more Sulfated ␤-cyclodextrin was synthesized from sulfonation of ␤-cyclodextrin and sulfated polymer was crosslinked with cotton fabric using ethylenediaminetetraacetic acid as crosslinker. ZnO, TiO 2 and Ag nanoparticles were prepared and characterized by XRD, UV, DLS, SEM and PSA. The prepared nanoparticles were coated on crosslinked cotton fabric. The crosslinking and nanoparticles coating effects of cotton fabrics were studied by FTIR and SEM analysis. The antibacterial test was done against gram positive Staphylococcus aureus and gram negative Escherichia coli bacterium.

Asian Pacific journal of tropical medicine, 2011

To identify the larvicidal activities of silver nano particles synthesised with Rhizophora mucron... more To identify the larvicidal activities of silver nano particles synthesised with Rhizophora mucronata (R. mucronata) leaf extract against the larvae of Aedes aegypti (Ae. aegypti) and Culex quinquefasciatus (Cx. quinquefasciatus). In vitro larvicidal activities such as LC(50) and LC(90) were assessed for the Ae. aegypti and Cx. quinquefasciatus larval species. Further, characterisation such as UV, XRD, FTIR and AFM analysis were carried out for the synthesised silver nano particles. The LC(50) value of the synthesised silver nano particle was identified as 0.585 and 0.891 mg/L for Ae. aegypti and Cx. quinquefasciatus larvae respectively. Further, the LC(90) values are also identified as 2.615 and 6.291 mg/L for Ae. aegypti and Cx. quinquefasciatus species respectively. The synthesised silver nanoparticles have maximum absorption at 420 nm with the average size of 60-95 nm. The XRD data showed 2θ intense values with various degrees such as 37.10°, 47.66°, 63.97° and 70.01°. The FTIR d...

Asian Pacific journal of tropical medicine, 2012

To identify the antibacterial potential of seagrass (Syringodium isoetifolium) associate microbes... more To identify the antibacterial potential of seagrass (Syringodium isoetifolium) associate microbes against bacterial pathogens. Eumeration of microbial associates were analyzed with leaf and root samples of Syringodium isoetifolium. MIC and MBC were calculated for bacterial pathogens with microbial associates. Phylogenetic and GC-MS analysis were calculated for Actinomycetes sp. (Act01) which was the most potent. Of the isolated microbial associates phosphatase producing bacterial isolates were identified as maximum [(261.78±35.09) CFU×10(4)/g] counts in root sample. Of the selected microbial isolates Actinomycete sp (Act01) showed broad spectrum of antibacterial activity against antibiotic resistant and fish bacterial pathogens. Phylogenetic analysis of Act01 showed maximum identities (99%) with the Streptomyces sp. (GU5500072). The 16s rDNA secondary structure of Act01 showed the free energy values as -366.3 kkal/mol. The GC-MS analysis Act01 showed maximum retention value with 23....

Asian Pacific Journal of Tropical Biomedicine, 2011

Aedes aegypti is the carrier of dengue hemorrhagic fever that remains an important public health ... more Aedes aegypti is the carrier of dengue hemorrhagic fever that remains an important public health issue in various tropical countries, especially Thailand. The use of synthetic pesticides increases the mosquito resistance and leads to change the mosquito behavior. Recently, plant extracts and their products have become increasing popular for use as alternative natural agents in mosquito control. Hence, this research aimed to investigate the efficacy of the parasitic plant extracts from Paederia pilifera and Cuscuta reflexa for killing the early 3 rd stage-larvae of Ae. aegypti. Both dry plants were separately extracted by maceration with 95% ethanol for 72 h, then filtered and evaporated using vacuum evaporator until dryness. The mosquito larvicidal activity was evaluated after 24 h exposure at different concentrations [0 (control), 25, 50, 100, 200, 400 and 800 ppm]. The results revealed that the C. reflexa extract gave the higher effectiveness to eliminate mosquito larvae than the P. pilifera extract with LC 50 and LC 90 of 80.55 and 297.94 ppm, respectively. Therefore, current investigation suggests that these plants extracts can be applied as alternative sources of mosquito larvicides. Further studies are needed for identification of the active compounds that can be used in broad spectrum for controlling mosquitoes and also for the determination of the mode of action of these compounds.

Parasitology Research, 2010

Antimirobial potential of sponge associated microorganisms have been dealt for a couple of centur... more Antimirobial potential of sponge associated microorganisms have been dealt for a couple of centuries, but the bioactivity of sponge associated macroorganism have not been attempted so far. The present study was carried out to find out the sponge associated macroorganism and their bioactive potential against chosen fish pathogens. Marine sponges were monthly collected by scuba diving at sampling station viz Thondi. Five sponge samples viz., Clathria vulpine, Stylissa carteri, Hyattella intestinalis, Clathria indica and Haliclona grant were collected from Palk Starit region. Associated macroorganism viz., Hypnea valentiae sponge and Nereis sp. The bioactive potential of sponge extract and associated macrofaunal and floral extract was showed that, the crude extract from Clathria vulpine showed maximum average zone of inhibition (10.25mm) against Bacillus subtilis and Vibrio harveyi. Among the assoiated macroorganisms, the seaweed Hypnea valentia and Nereis sp showed maximum average zone of inhibition (9.25 and 7.5mm). The overall antimicrobial activity assessed from the above results indicated the presence of active constituents in the extractions of sponges and assoiated macroorganisms which can be exploited for the production of lead molecules which are of use in pharmaceutical industry.

Parasitology Research, 2010

Mosquitoes transmit serious human diseases, causing millions of deaths every year. Use of synthet... more Mosquitoes transmit serious human diseases, causing millions of deaths every year. Use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of botanical origin have been reported as useful for control of mosquitoes. Mangrove plants of Exoecaria agallocha bark extract its derived products have shown a variety of insecticidal properties. The present paper discusses the larvicidal activity of mangrove plants against some followed by Culex quinquefasciatus, Anopheles stephensi and Aedes aegypti. In our result suggested that the highest mortality was found in methanol, aqueous, against the larvae of Anopheles stephensi

Andrologia, 2013

Contraceptive properties of seaweeds are still stands as lacuna; in this context, the screening o... more Contraceptive properties of seaweeds are still stands as lacuna; in this context, the screening of in vitro male contraceptive properties of crude ethanolic extract of Indian seaweeds against normal human sperm is carried out. In total, twelve seaweeds were screened for in vitro spermicidal activity. Among these twelve seaweeds, Halimeda gracilis showed 100% inhibition of human spermatozoa at 10 mg ml(-1) concentration in 20 s and its EC50 value was 2.05 mg ml(-1) in 20 s. Further, dose- and time-dependent spermicidal assay revealed that the sperm was completely immobilised for 20 s. Plasma membrane of sperm was damaged due to the exposure of H. gracilis extract. MTT assay with H. gracilis extract showed 88.5% of cytotoxic incidence. H. gracilis extract tested for cytotoxicity against Artemia salina recorded LC50 value of 34.8 μg ml(-1) . Phytochemical analysis of H. gracilis extract evidenced the presence of alkaloids, flavonoids, proteins and sugars. Results of this study clearly inferred that the synergistic effect of active principles reside within the H. gracilis extract had shown better contraceptive activity.

International Journal of Drug Delivery, 2010

Background: Dietary phytohormones may influence the metabolic processes in animal cells. To deter... more Background: Dietary phytohormones may influence the metabolic processes in animal cells. To determine the effect of the plant growth regulators 28homobrassinolide, gibberellic acid and kinetin on the tissue hexokinase and some blood components in male rats. Methods: 50µg 28-bomobrassinolide, gibberellic acid and kinetin (Normal saline served as control) was injected intradermally. Hexokinase activity in several tissues and blood level of glucose, hemoglobin and cholesterol were determined 2 h after injection. Findings: 28-homobrassinolide increased hexokinase activity in all tissues studied, and reduced blood glucose level but increased hemoglobin and cholesterol level. Gibberellic acid increased hexokinase activity in liver, but decreased it in other tissues and increased significantly blood cholesterol and slightly glucose and hemoglobin levels. Kinetin decreased hexokinase activity significantly in liver and kidney, but not significantly in other tissues, and reduced slightly glucose and hemoglobin levels and reduced significantly serum cholesterol level. Conclusion: This study indicated that treatment of rat with 28-homobrassinolide significantly increased hexokinase activity in liver, heart and kidney whereas gibberellic acid increased hexokinase activity only in the liver, and Kinetin decreased hexokinase activity in most tissues. Decreased hexokinase activity was observed due to kinetin and gibberellic acid treatment, except for gibberellic acid in the liver tissue, and was indicative of the fact that kinetin and gibberellic acid acted as negative modulators of this enzyme in the rat tissues. Thus, three different phytohormones possessed different degrees of effect in the animal cells.

International Journal of Biological and Chemical Sciences, 2010

The in vitro antibacterial activity of column chromatographic fractions of n-hexane, benzene, chl... more The in vitro antibacterial activity of column chromatographic fractions of n-hexane, benzene, chloroform, acetone, ethanol and water extracts of Excoecaria agallocha L. were determined against 24 localized and common bacterial pathogens. Antibacterial assay was performed by agar diffusion method against 4 specialized urinary tract pathogens, 10 antibiotic sensitive ophthalmic bacterial pathogens, 5 antibiotic resistant bacterial pathogens and 5 fish pathogens. It was found that the 11 th fraction of chloroform extract and the 30 th fraction of water extract exhibited broad spectrum of antibacterial activity. These 2 active fractions were further investigated through UV-Visible, NMR and FT-IR and were characterized as benzoate and diterpenes and their derivatives viz., 2,3-secoatisane type diterpene and 3,4,5-trihydroxy methyl benzoate.

Biomedicine & Pharmacotherapy, 2010

The Publisher regrets that this article is an accidental duplication of an article that has alrea... more The Publisher regrets that this article is an accidental duplication of an article that has already been published, http://dx.doi.org/10.1016/j.bionut.2010.09.001. The duplicate article has therefore been withdrawn.

International Journal of Medicine and Medical Sciences, May 30, 2009

Forty-five crude methanolic extracts from 23 marine halophytes were screened against five bacteri... more Forty-five crude methanolic extracts from 23 marine halophytes were screened against five bacterial and two fungal saprophytic pathogens of diseased silkworm Bombyx mori. Among thirty-four mangrove samples screened for antibacterial activity, the leaf extract of Rhizophora mucronata showed maximum inhibitory activity against Staphylococcus aureus (20 mm dia.). The seaweed species of Padina tetrostomatica showed maximum inhibitory activity against Proteus vulgaris (11 mm dia) and the seagrass species of Syringodium isoetifolium showed maximum inhibition against P. vulgaris (9 mm dia). The solar saltern cyanobacterium Phormidium fragile exhibits higher inhibitory activity against P. vulgaris (17 mm dia). The growth of fungal pathogens of Aspergillus niger was highly inhibited by S. isoetifolium (15 mm dia) and Padina tetrostomatica (13 mm dia) respectively compared with the other extracts. It is also noted that 16x concentration of the leaf extract of R. mucronata and S. isoetifolium showed complete reduction in the bacterial and fungal viable counts within 3 h of exposure.

International Journal of Current Research in Biosciences and Plant Biology, 2016

Medicinal plants have a long history of use and their use is widespread in both developing and de... more Medicinal plants have a long history of use and their use is widespread in both developing and developed countries. From the last few decades, there is an increasing interest in formation of the drugs derived from plants which helps to control diseases. Also the herbal products are safer than synthetic products which may be harmful and unsafe to the human and environment. The present study made an attempt to find out the antidiabetic property of Costus species. Fresh elder leaves of species viz., Costus pictus and Costus speciosus were collected from Western Ghats, Tamil Nadu. The plant samples were washed thoroughly and extracted in ethanolic solvent. In in vitro αamylase inhibitory study, the maximum inhibition of Costus pictus was of 88.75% at a concentration 400µg.ml-1. In starch iodine color assay, the maximum inhibition of color change of extract at 400µg.ml-1. Glucose uptake inhibition assay data suggests Costus species is significant in inhibiting glucose diffusion. It is concluded from the present study that the Costus species extracts potentiate the antidiabetic activity and can be used as an alternate for the treatment of diabetes after completing successful clinical trials.

Journal of environmental biology / Academy of Environmental Biology, India, 2009

Anti-inflammatory drugs presently available for the treatment of various inflammatory disorders h... more Anti-inflammatory drugs presently available for the treatment of various inflammatory disorders have diverse and undesirable side effects. In recent years; active principles of varied chemical structures have been isolated from plants possessing anti-inflammatory activity. Sulfated polysaccharides present in algae were shown to posses anti-inflammatory properties. Ulva lactuca the green alga available in Tuticorin coast was found to show anti-inflammatory effect as evidenced by the reduction in the inhibition of oedema at the 4th day of the experiment compared with the positive control drug and control. Microscopic examination of the elite organs did not show any alteration compared with the control and reference group. Moreover the hematological parameters were found normal compared with the control. The present study suggests the need for further studies for the development of anti-inflammatory drug of marine origin with proper clinical trials.

World Applied Sciences …, 2011

Asian Pacific journal of tropical medicine, 2011

To identify the in vitro antiplasmodial activity of seaweed plants against Plasmodium falciparums... more To identify the in vitro antiplasmodial activity of seaweed plants against Plasmodium falciparumstrains. A total of eight seaweeds were collected from Kanyakumari district, Tamilnadu, India. The in vitro antiplasmodial activity was performed in 96 well plates against Plasmodium falciparum, and preliminary phytochemcial analysis were performed for the extracts. Of the selected plants Enteromorpha intestinalis (2.61%) showed maximum percentage of extraction. The minimum concentration of inhibitory (IC50) value was observed with Chaetomorpha antennina [(26.37±4.14) μg/mL] further, the positive controls such as chloroquine and artemether showed antiplasmodial activities (IC50) with (19.10±5.93) and (6.03±0.21) μg/mL concentrations, respectively. The preliminary phytochemical analysis of the seaweed extracts showed a variety of phytochemical constituents such as carboxylic acids, phenols, protein, resins, steroids and sugars. The antiplasmodial activity of the seaweed extract might due t...

International Journal of Medicine and Medical Sciences, 2013

The objective of the study was to evaluate the antibacterial activities of N,N’[1,1’-dithiobis(ph... more The objective of the study was to evaluate the antibacterial activities of N,N’[1,1’-dithiobis(phenylene)]bis(benzyldeneimine), referred to as L1 and o,o’-(N,N-dipicolinyldene) diazadiphenyldisulfide, referred to as L2, containing disulfide moieties against some ophthalmic pathogens (Klebsiella species, Escherichia coli, Streptococcus species, Proteus morganii, Pseudomonas species, Streptococcus pneumoniae, Acinetobacter species, Streptococcus pyogenes and Streptococcus viridans), urinary tract infectious pathogens (P. morganii, E. coli, Pseudomonas spp., Enterobacter species, and Klebsiella spp.) and antibiotic resistant pathogens (Staphylococcus species, Streptococcus, Pseudomonas spp., and Klebsiella spp.) for minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The MIC for the ophthalmic pathogens and antibiotic resistant pathogens were found to be 400 to 500 µg/ml, while for the urinary tract infectious pathogens a lower MIC value (200 µg/ml) was...

Journal of environmental biology / Academy of Environmental Biology, India, 2010

Study of marine organisms for their bioactive potential, being an important part of marine ecosys... more Study of marine organisms for their bioactive potential, being an important part of marine ecosystem, has picked up the rhythm in recent years with the growing recognition of their importance in human life. Investigation was carried out to isolate 32 strains of endo and epiphytic bacteria in 2 seagrass species viz., Syringodium isoetifolium and Cymodocea serrulata. Morphologically different bacterial strains were tested against 5 antibiotic resistant human bacterial pathogens, of which 10 associated bacteria shown inhibitory activity against one or more bacterial pathogens. Minimum inhibitory concentration (MIC) and Minimum bacterial concentration (MBC) determination with extracellular bioactive compounds from the associated bacteria reveals that, the strain ENC 5 showed inhibitory activity against all the bacterial pathogens with the maximum sensitivity against Pseudomonas aeruginosa at the MIC value of 500 microg ml(-1).

International Journal of Pharmaceutics, 2012

Sulfated ␤-cyclodextrin was synthesized from sulfonation of ␤-cyclodextrin and sulfated polymer w... more Sulfated ␤-cyclodextrin was synthesized from sulfonation of ␤-cyclodextrin and sulfated polymer was crosslinked with cotton fabric using ethylenediaminetetraacetic acid as crosslinker. ZnO, TiO 2 and Ag nanoparticles were prepared and characterized by XRD, UV, DLS, SEM and PSA. The prepared nanoparticles were coated on crosslinked cotton fabric. The crosslinking and nanoparticles coating effects of cotton fabrics were studied by FTIR and SEM analysis. The antibacterial test was done against gram positive Staphylococcus aureus and gram negative Escherichia coli bacterium.

Asian Pacific journal of tropical medicine, 2011

To identify the larvicidal activities of silver nano particles synthesised with Rhizophora mucron... more To identify the larvicidal activities of silver nano particles synthesised with Rhizophora mucronata (R. mucronata) leaf extract against the larvae of Aedes aegypti (Ae. aegypti) and Culex quinquefasciatus (Cx. quinquefasciatus). In vitro larvicidal activities such as LC(50) and LC(90) were assessed for the Ae. aegypti and Cx. quinquefasciatus larval species. Further, characterisation such as UV, XRD, FTIR and AFM analysis were carried out for the synthesised silver nano particles. The LC(50) value of the synthesised silver nano particle was identified as 0.585 and 0.891 mg/L for Ae. aegypti and Cx. quinquefasciatus larvae respectively. Further, the LC(90) values are also identified as 2.615 and 6.291 mg/L for Ae. aegypti and Cx. quinquefasciatus species respectively. The synthesised silver nanoparticles have maximum absorption at 420 nm with the average size of 60-95 nm. The XRD data showed 2θ intense values with various degrees such as 37.10°, 47.66°, 63.97° and 70.01°. The FTIR d...

Asian Pacific journal of tropical medicine, 2012

To identify the antibacterial potential of seagrass (Syringodium isoetifolium) associate microbes... more To identify the antibacterial potential of seagrass (Syringodium isoetifolium) associate microbes against bacterial pathogens. Eumeration of microbial associates were analyzed with leaf and root samples of Syringodium isoetifolium. MIC and MBC were calculated for bacterial pathogens with microbial associates. Phylogenetic and GC-MS analysis were calculated for Actinomycetes sp. (Act01) which was the most potent. Of the isolated microbial associates phosphatase producing bacterial isolates were identified as maximum [(261.78±35.09) CFU×10(4)/g] counts in root sample. Of the selected microbial isolates Actinomycete sp (Act01) showed broad spectrum of antibacterial activity against antibiotic resistant and fish bacterial pathogens. Phylogenetic analysis of Act01 showed maximum identities (99%) with the Streptomyces sp. (GU5500072). The 16s rDNA secondary structure of Act01 showed the free energy values as -366.3 kkal/mol. The GC-MS analysis Act01 showed maximum retention value with 23....

Asian Pacific Journal of Tropical Biomedicine, 2011

Aedes aegypti is the carrier of dengue hemorrhagic fever that remains an important public health ... more Aedes aegypti is the carrier of dengue hemorrhagic fever that remains an important public health issue in various tropical countries, especially Thailand. The use of synthetic pesticides increases the mosquito resistance and leads to change the mosquito behavior. Recently, plant extracts and their products have become increasing popular for use as alternative natural agents in mosquito control. Hence, this research aimed to investigate the efficacy of the parasitic plant extracts from Paederia pilifera and Cuscuta reflexa for killing the early 3 rd stage-larvae of Ae. aegypti. Both dry plants were separately extracted by maceration with 95% ethanol for 72 h, then filtered and evaporated using vacuum evaporator until dryness. The mosquito larvicidal activity was evaluated after 24 h exposure at different concentrations [0 (control), 25, 50, 100, 200, 400 and 800 ppm]. The results revealed that the C. reflexa extract gave the higher effectiveness to eliminate mosquito larvae than the P. pilifera extract with LC 50 and LC 90 of 80.55 and 297.94 ppm, respectively. Therefore, current investigation suggests that these plants extracts can be applied as alternative sources of mosquito larvicides. Further studies are needed for identification of the active compounds that can be used in broad spectrum for controlling mosquitoes and also for the determination of the mode of action of these compounds.

Parasitology Research, 2010

Antimirobial potential of sponge associated microorganisms have been dealt for a couple of centur... more Antimirobial potential of sponge associated microorganisms have been dealt for a couple of centuries, but the bioactivity of sponge associated macroorganism have not been attempted so far. The present study was carried out to find out the sponge associated macroorganism and their bioactive potential against chosen fish pathogens. Marine sponges were monthly collected by scuba diving at sampling station viz Thondi. Five sponge samples viz., Clathria vulpine, Stylissa carteri, Hyattella intestinalis, Clathria indica and Haliclona grant were collected from Palk Starit region. Associated macroorganism viz., Hypnea valentiae sponge and Nereis sp. The bioactive potential of sponge extract and associated macrofaunal and floral extract was showed that, the crude extract from Clathria vulpine showed maximum average zone of inhibition (10.25mm) against Bacillus subtilis and Vibrio harveyi. Among the assoiated macroorganisms, the seaweed Hypnea valentia and Nereis sp showed maximum average zone of inhibition (9.25 and 7.5mm). The overall antimicrobial activity assessed from the above results indicated the presence of active constituents in the extractions of sponges and assoiated macroorganisms which can be exploited for the production of lead molecules which are of use in pharmaceutical industry.

Parasitology Research, 2010

Mosquitoes transmit serious human diseases, causing millions of deaths every year. Use of synthet... more Mosquitoes transmit serious human diseases, causing millions of deaths every year. Use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of botanical origin have been reported as useful for control of mosquitoes. Mangrove plants of Exoecaria agallocha bark extract its derived products have shown a variety of insecticidal properties. The present paper discusses the larvicidal activity of mangrove plants against some followed by Culex quinquefasciatus, Anopheles stephensi and Aedes aegypti. In our result suggested that the highest mortality was found in methanol, aqueous, against the larvae of Anopheles stephensi

Andrologia, 2013

Contraceptive properties of seaweeds are still stands as lacuna; in this context, the screening o... more Contraceptive properties of seaweeds are still stands as lacuna; in this context, the screening of in vitro male contraceptive properties of crude ethanolic extract of Indian seaweeds against normal human sperm is carried out. In total, twelve seaweeds were screened for in vitro spermicidal activity. Among these twelve seaweeds, Halimeda gracilis showed 100% inhibition of human spermatozoa at 10 mg ml(-1) concentration in 20 s and its EC50 value was 2.05 mg ml(-1) in 20 s. Further, dose- and time-dependent spermicidal assay revealed that the sperm was completely immobilised for 20 s. Plasma membrane of sperm was damaged due to the exposure of H. gracilis extract. MTT assay with H. gracilis extract showed 88.5% of cytotoxic incidence. H. gracilis extract tested for cytotoxicity against Artemia salina recorded LC50 value of 34.8 μg ml(-1) . Phytochemical analysis of H. gracilis extract evidenced the presence of alkaloids, flavonoids, proteins and sugars. Results of this study clearly inferred that the synergistic effect of active principles reside within the H. gracilis extract had shown better contraceptive activity.