Search

Your search keyword '"Goveas, Louella Concepta"' showing total 45 results
Start Over Author "Goveas, Louella Concepta" Publication Year Range Last 3 years
45 results on '"Goveas, Louella Concepta"'

38. Biosorption of Pb (II) by extracellular polymeric substance of <italic>Lysinibacillus</italic> sp. SS1: optimization, kinetics, and isotherms.

Author

Rao U, Kiran, Goveas, Louella Concepta, Arun, Anagha, and Gokhale, Abhilash

Subjects
*LEAD, *RESPONSE surfaces (Statistics), *WATER pollution, *BIOSORPTION, *DRINKING water
Abstract

AbstractWater pollution with potentially toxic elements is a critical public health problem today. An extracellular polymeric substance (EPS) extracted from Lysinibacillus sp. SS1 was used for the adsorptive removal of lead. One-variable-at-a-time method was used to obtain maximum adsorption of 87% at 25 mg/L lead, 25 mg/L EPS, pH 6, temperature of 27 °C, agitation speed of 80 RPM. Response surface methodology gave optimum conditions of 3.79 mg/L of EPS and 108 RPM corresponding to 97.92% of lead removal at contact time of 60 min. The data for adsorption process fit Temkin isotherm and pseudo-second order kinetic model (k = 3.348 × 10−4 mg/g.min and Qe = 824.34 mg/g), confirming monolayer-multilayer chemisorption process with liquid-film diffusion regulating the reaction rate. Positive values of ΔHo, ΔGo, and ΔSo confirmed the biosorption process to be endothermic, non-spontaneous and exhibiting increased randomness at the biosorptive interface. The adsorption of lead by EPS showed no significant change in a mixture containing zinc, magnesium, cadmium, cobalt, and iron. Hence, EPS produced by Lysinibacillus sp. SS1 can be a highly efficient, eco-friendly method of treating low concentrations of lead pollution in drinking water. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

41. Stable silver nanoparticles synthesis using Tabebuia aurealeaf extract for efficient water treatment: A sustainable approach to environmental remediation

Author

Selvaraj, Raja, Nagendran, Vasundra, Varadavenkatesan, Thivaharan, Goveas, Louella Concepta, and Vinayagam, Ramesh

Abstract

Noble metal nanoparticles have garnered significant attention owing to their extensive utility across various domains. Among them, silver nanoparticles (SNP) deliver solutions to various environmental problems in the area of water treatment. SNP are conventionally fabricated using chemical methods with toxic chemicals. In this work, we used leaf extract of Tabebuia aureato rapidly synthesize stable silver nanoparticles (TA-SNP). The analysis of the UV–vis spectrum revealed surface plasmon resonance at 438 nm which confirmed the formation of SNP. The SEM image showed the nanosized and spherical morphology of the TA-SNP with a mean size of 48.68 nm. XRD pattern of nanoparticles pertaining to (101) plane, ascertained the fcc crystal arrangement with 19.36 nm as crystallite diameter. DLS confirmed the colloidal stability with a zeta potential of −26.7 mV. The FTIR studies suggest that the presence of various functional moieties of the leaf extract is accountable for the formation and capping of nanoparticle synthesis. The efficiency of TA-SNP as a potential catalyst in the reduction of the Congo Red and Acid Blue 113 dye with NaBH4was demonstrated with first-order kinetic constants of 0.2723 and 0.1335 min –1respectively. Hence, the environmentally friendly and cost-effective synthesis method used for SNP in the present study holds promise for developing nanocatalysts aimed at effectively removing diverse dyes from wastewater, thereby contributing to environmental remediation.

Published
2024
Full Text
View/download PDF

42. Recent advances in fermentative biohydrogen production.

Author

Goveas, Louella Concepta, Nayak, Sneha, Kumar, P. Senthil, Vinayagam, Ramesh, Selvaraj, Raja, and Rangasamy, Gayathri

Subjects
*MICROBIAL genomes, *POWER resources, *ALTERNATIVE fuels, *GENETIC engineering, *LIQUID hydrogen, *HYDROGEN as fuel, *HYDROGEN production
Abstract

Utilization of unsustainable fossil fuels as energy resources releases greenhouse gases into the atmosphere leading to global warming and environmental pollution. An eye-catching solution would be the production of biological liquids like hydrogen, which is a clean renewable fuel using dark/light fermentative approach. A brief insight into the effect of parameters that could enhance H 2 production is the major focus of this review. Although dark/light fermentative approaches for H 2 production is known for quite long, scaling up this technology has seen major hurdles. The review thus throws light on the need for novel tactics such as microbial immobilization, nanotechnologies, and genetic engineering to varying the microbial genomes for improvement of H 2 yield. Further, thoughts on the difficulties that could be faced and potential solutions about the prospects for H 2 technology to be commercially used as a sustainable fuel in the near future are also emphasized. [Display omitted] • Mechanisms of photo and dark fermentation for hydrogen - simplified. • Factors influencing fermentative hydrogen production. • Tactics to enhance biohydrogen production. • Possible hurdles and future prospects – large scale implementation. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

44. Characterization of biosurfactant produced in response to petroleum crude oil stress by Bacillussp. WD22 in marine environment

Author

Goveas, Louella Concepta, Selvaraj, Raja, and Sajankila, Shyama Prasad

Abstract

Bacillussp. WD22, previously isolated from refinery effluent, degraded 71% of C8 hydrocarbons present in 1.0% v/v PCO in seawater (control medium), which reduced to 16.3%, on addition of yeast extract. The bacteria produced a biosurfactant in both media, whose surface was observed to be amorphous in nature under FESEM-EDAX analysis. The biosurfactant was characterized as a linear surfactin by LCMS and FT-IR analysis. The critical micelle concentration was observed as 50 mg/L and 60 mg/L at which the surface tension of water was reduced to 30 mN/m. Purified biosurfactant could emulsify petroleum-based oils and vegetable oils effectively and was stable at all tested conditions of pH, salinity and temperature up to 80 °C. The biosurfactant production was found to be mixed growth associated in control medium, while it was strictly growth associated in medium with yeast extract as studied by the Leudeking-Piret model.

Published
2022
Full Text
View/download PDF

45. Rhamnolipid assisted degradation of petroleum crude oil by indigenous Pseudomonassp. WDE11 in seawater

Author

Goveas, Louella Concepta, Selvaraj, Raja, Vinayagam, Ramesh, and Sajankila, Shyama Prasad

Abstract

Chronic and acute release of petroleum crude into oceans and seas leads to catastrophic effects on ecosystems and global climate. Employing effective strategies for the mitigation of petroleum crude pollution in the marine environment is the need of the hour. An indigenous strain of Pseudomonas(sp. WDE11), with polyaromatic hydrocarbon degrading abilities, degraded 1% petroleum crude oil (PCO) effectively in seawater on supplementation of glucose (1.0 g/L). Degradation was assisted by biosurfactant with low CMC (15.0 g/L) and was characterized as a rhamnolipid by FESEM-EDAX, LCMS, and FT-IR analysis. Glucose and inoculum depicted curvature amongst other tested parameters (incubation time, PCO, pH, and agitation speed via OPAT approach, and were subsequently optimized to maximum degradation using Pseudomonassp. WDE11 by a 22central composite design method. The highest degradation of 80 ± 0.15% of 1.0% PCO was achieved at 2.53 g/L glucose and 8.18% inoculum, as optimized conditions. GC/MS analysis depicted the degradation of all major hydrocarbons present in PCO on comparing with abiotic control. This study indicates the potential of Pseudomonassp. WDE11 in the eradication of petroleum pollution from the contaminated marine environment under nutrient-limited conditions.

Published
2024
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results