The Experts below are selected from a list of 412356 Experts worldwide ranked by ideXlab platform
K Bharathi - One of the best experts on this subject based on the ideXlab platform.
-
plant extract mediated synthesis of zno nanoparticles using pongamia pinnata and their activity against pathogenic bacteria
Advanced Powder Technology, 2015Co-Authors: M Sundrarajan, Subramanian Ambika, K BharathiAbstract:Abstract Bio-mediated synthesis of metal oxide nanoparticles using plant extract is a promising alternative of traditional chemical synthesis. The present study reports the synthesis of ZnO nanoparticles by Biological Method. Highly stable and hexagonal phase ZnO nanoparticles were synthesized using Pongamia pinnata leaves extract and were characterized by XRD, UV–vis, DLS, SEM, TEM and FT-IR spectroscopy. The synthesized ZnO nanoparticles were confirmed by XRD and FTIR spectra. Morphology studies indicates spherical nature of the ZnO NPs and EDX shows the highly pure ZnO nanoparticles. The antibacterial activity of ZnO nanoparticles and ZnO nanoparticles coated cotton fabric were tested against Staphylococcus aureus (gram positive) and Escherichia coli (gram negative) organisms by agar diffusion Method. Finally, the current study has clearly demonstrated that the ZnO NPs are responsible for significant higher antibacterial activities. Therefore, the study reveals an efficient, ecofriendly and simple Method for the green synthesis of multifunctional ZnO NPs using green synthetic approach.
Rajiv Kumar - One of the best experts on this subject based on the ideXlab platform.
-
Fungus-Mediated Synthesis of Silver Nanoparticles and Their Immobilization in the Mycelial Matrix: A Novel Biological Approach to Nanoparticle Synthesis
Nano Letters, 2001Co-Authors: Priyabrata Mukherjee, Renu Parishcha, P. V. Ajaykumar, Mohammad I. Khan, Deendayal Mandal, Absar Ahmad, Satyajyoti Senapati, S R Sainkar, Mansoor Alam, Rajiv KumarAbstract:A novel Biological Method for the synthesis of silver nanoparticles using the fungus Verticillium is reported. Exposure of the fungal biomass to aqueous Ag+ ions resulted in the intracellular reduction of the metal ions and formation of silver nanoparticles of dimensions 25 ± 12 nm. Electron microscopy analysis of thin sections of the fungal cells indicated that the silver particles were formed below the cell wall surface, possibly due to reduction of the metal ions by enzymes present in the cell wall membrane. The metal ions were not toxic to the fungal cells and the cells continued to multiply after biosynthesis of the silver nanoparticles.
Jae Hyung Shim - One of the best experts on this subject based on the ideXlab platform.
-
Feeding by the heterotrophic dinoflagellate Oxyrrhis marina on the red-tide raphidophyte Heterosigma akashiwo: a potential Biological Method to control red tides using mass-cultured grazers.
The Journal of Eukaryotic Microbiology, 2003Co-Authors: Hae Jin Jeong, Jae Seong Kim, Yeong Du Yoo, Seong Taek Kim, Tae Hoon Kim, Myung Gil Park, Chang-hoon Lee, Kyeong Ah Seong, Nam Seon Kang, Jae Hyung ShimAbstract:Abstract As part of the development of a Method to control the outbreak and persistence of red tides using mass-cultured heterotrophic protist grazers, we measured the growth and ingestion rates of cultured Oxyrrhis marina (a heterotrophic dinoflagellate) on cultured Heterosigma akashiwo (a raphidophyte) in bottles in the laboratory and in mesocosms (ca. 60 liter) in nature, and those of the cultured grazer on natural populations of the red-tide organism in mesocosms set up in nature. In the bottle incubation, specific growth rates of O. marina increased rapidly with increasing concentration of cultured prey up to ca. 950 ng C ml−1 (equivalent to 9,500 cells ml−1), but were saturated at higher concentrations. Maximum specific growth rate (μmax), KGR (prey concentration sustaining 0.5 μmax) and threshold prey concentration of O. marina on H. akashiwo were 1.43 d−1, 104 ng C ml−1, and 8.0 ng C ml−1, respectively. Maximum ingestion and clearance rates of O. marina were 1.27 ng C grazer−1 d−1 and 0.3 μl graze...
A. B. Mandal - One of the best experts on this subject based on the ideXlab platform.
-
Biological Method for decolourisation of an azo dye: clean technology to reduce pollution load in dye waste water
Clean Technologies and Environmental Policy, 2012Co-Authors: J. Kanagaraj, T. Senthil Velan, A. B. MandalAbstract:A bacterium isolated and identified as Bacillus cereus from tannery effluent was employed for decolourisation of an azo dye. This strain rapidly decolourises the Acid Black dye sample that belongs to azo category. The optimum activity of B . cereus was found at pH 7.3, temperature 37°C, and duration of 4 days. The decolourisation rate was found out to be 80 and 96% for the agitated and static conditions. UV–vis spectra analysis showed that the peaks which appeared in the visible region of the treated dye disappeared, indicating complete decolourisation of dye. The FT-IR analysis for the B. cereus treated sample showed the transformation of azo linkage into N_2 or NH_3 or incorporated into complete biomass. The presence of aromatic amine in the decolourised sample indicated the presence of azoreductase activity. The mass spectra analysis showed the conversion of the azo dye into new intermediate metabolites such as p -nitroaniline, 2,8 diamino, 3,6 dithio 1-napthanol, and 2,8 diamino-1-napthalol with mol. wt. of 139, 240, and 174, respectively. COD and TOC values of the B. cereus treated sample showed reduction of 85 and 87%, respectively at 120 h duration.
M Sundrarajan - One of the best experts on this subject based on the ideXlab platform.
-
plant extract mediated synthesis of zno nanoparticles using pongamia pinnata and their activity against pathogenic bacteria
Advanced Powder Technology, 2015Co-Authors: M Sundrarajan, Subramanian Ambika, K BharathiAbstract:Abstract Bio-mediated synthesis of metal oxide nanoparticles using plant extract is a promising alternative of traditional chemical synthesis. The present study reports the synthesis of ZnO nanoparticles by Biological Method. Highly stable and hexagonal phase ZnO nanoparticles were synthesized using Pongamia pinnata leaves extract and were characterized by XRD, UV–vis, DLS, SEM, TEM and FT-IR spectroscopy. The synthesized ZnO nanoparticles were confirmed by XRD and FTIR spectra. Morphology studies indicates spherical nature of the ZnO NPs and EDX shows the highly pure ZnO nanoparticles. The antibacterial activity of ZnO nanoparticles and ZnO nanoparticles coated cotton fabric were tested against Staphylococcus aureus (gram positive) and Escherichia coli (gram negative) organisms by agar diffusion Method. Finally, the current study has clearly demonstrated that the ZnO NPs are responsible for significant higher antibacterial activities. Therefore, the study reveals an efficient, ecofriendly and simple Method for the green synthesis of multifunctional ZnO NPs using green synthetic approach.