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G. K. Suraishkumar

Bio: G. K. Suraishkumar is an academic researcher from Indian Institute of Technology Madras. The author has contributed to research in topics: Dysbiosis & Activated sludge. The author has an hindex of 11, co-authored 44 publications receiving 436 citations. Previous affiliations of G. K. Suraishkumar include Sree Chitra Thirunal Institute for Medical Sciences and Technology.

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TL;DR: Although ROS reactions are extremely rapid, the siROS level can be assumed to be at pseudo‐steady state compared to the time scales of metabolism, growth and production, and hence they can be effective stress markers at particular time points.
Abstract: Microalgae have significant potential to be an important alternative energy source, but the challenges to the commercialization of bio-oil from microalgae need to be overcome for the potential to be realized. The application of stress can be used to improve bio-oil yields from algae. Nevertheless, the understanding of stress effects is fragmented due to the lack of a suitable, direct quantitative marker for stress. The lack of understanding seems to have limited the development of stress based strategies to improve bio-oil yields, and hence the commercialization of microalgae-based bio-oil. In this study, we have proposed and used the specific intracellular reactive species levels (siROS) particularly hydroxyl and superoxide radical levels, separately, as direct, quantitative, markers for stress, irrespective of the type of stress induced. Although ROS reactions are extremely rapid, the siROS level can be assumed to be at pseudo-steady state compared to the time scales of metabolism, growth and production, and hence they can be effective stress markers at particular time points. Also, the specific intracellular (si-) hydroxyl and superoxide radical levels are easy to measure through fluorimetry. Interestingly, irrespective of the conditions employed in this study, that is, nutrient excess/limitation or different light wavelengths, the cell concentrations are correlated to the siROS levels in an inverse power law fashion. The composite plots of cell concentration (y) and siROS (x) yielded the correlations of y = k1 · x(-0.7) and y = k2 · x(-0.79) , for si-hydroxyl and si-superoxide radical levels, respectively. The specific intracellular (si-) neutral lipid levels, which determine the bio-oil productivity, are related in a direct power law fashion to the specific hydroxyl radical levels. The composite plot of si-neutral lipid levels (z) and si-hydroxyl radical level (x) yielded a correlation of z = k3 · x(0.65) . More interestingly, a nutrient shift caused a significant change in the sensitivity of neutral lipid accumulation to the si-hydroxyl radical levels.

78 citations

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TL;DR: This study strongly suggests that the EPS mediated eco-corona formation may substantially lessen the toxic effects of nanoplastics as one of the major emerging pollutants in marine ecosystem.

66 citations

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TL;DR: A one-dimensional mathematical model based on linear equilibrium adsorption of bacteria has been developed to predict bacterial transport through porous media and it has been found that chemo tactic has a significant effect on bacterial transport, especially under conditions of considerable substrate gradient and at low pore velocity.

52 citations

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TL;DR: Biochemical and molecular evidences provided below strongly suggest that cell death under high shear results from an apoptosis‐like process similar to that described in eukaryotes, with activation of a caspase‐3‐like protease (C3LP) followed by DNA fragmentation.
Abstract: Exposure of Bacillus subtilis to a shear rate of 1,482/s leads to a rapid loss of cell viability after 10 h of growth. Biochemical and molecular evidences provided below strongly suggest that cell death under high shear results from an apoptosis-like process similar to that described in eukaryotes, with activation of a caspase-3-like protease (C(3)LP) followed by DNA fragmentation. Shear stress leads to an increase in specific intracellular reactive oxygen species (siROS), possibly through activation of NADH oxidase (NOX). The formation of siROS precedes the activation of C(3)LP and DNA fragmentation, thus establishing siROS as the molecular link between shear stress and apoptosis-like cell death. A model is proposed in which NOX is viewed as being strategically placed on the plasma membrane of B. subtilis that senses and converts a mechanical force arising from shear stress into a chemical signal leading to activation of C(3)LP, DNA fragmentation, and thus, apoptosis-like cell death.

44 citations

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TL;DR: In this paper, the co-digestion of mixed waste activated sludge (MWAS) and fruit and vegetable waste (FVW) was studied in a two-stage (thermophilic followed by mesophilic) semi-continuous anaerobic digester performance and stability.
Abstract: Co-digestion of mixed waste activated sludge (MWAS) and fruit and vegetable waste (FVW) was studied in a two-stage (thermophilic followed by mesophilic) semi-continuous anaerobic digestion to evaluate anaerobic digester performance and stability. A mixing ratio of 75 % MWAS and 25 % FVW showed a 1.6-fold increase in overall methane yield and achieved 0.38 volatile fatty acids to alkaline buffer capacity ratio (FOS/TAC) compared to mixture of 50 % MWAS and 50 % FVW. Application of hybrid (MW-H2O2) pretreatment in the former mixing ratio increased sludge solubilization by 33 % and consequently enhanced overall methane yield by 2.17-fold. The treated digester showed increased process stability with a FOS/TAC ratio of 0.26 as a consequence of buffer capacity offered by released biopolymers during pre-treatment. The generation of superoxide radicals during anaerobic digestion was studied and found to negatively correlate with sludge bioactivity. Two-stage digestion also minimizes the issue of high acidification due to co-digestion involving FVW.

39 citations


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1,633 citations

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TL;DR: In this article, the authors highlight recent advances in understanding of the core molecular clock and how it utilizes diverse transcriptional and post-transcriptional mechanisms to impart temporal control onto mammalian physiology.
Abstract: Circadian clocks coordinate physiology and behavior with the 24h solar day to provide temporal homeostasis with the external environment. The molecular clocks that drive these intrinsic rhythmic changes are based on interlocked transcription/translation feedback loops that integrate with diverse environmental and metabolic stimuli to generate internal 24h timing. In this review we highlight recent advances in our understanding of the core molecular clock and how it utilizes diverse transcriptional and post-transcriptional mechanisms to impart temporal control onto mammalian physiology. Understanding the way in which biological rhythms are generated throughout the body may provide avenues for temporally directed therapeutics to improve health and prevent disease.

702 citations

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TL;DR: This review article reviews the new role of colloidal fines in contaminant retardation due to plugging of pore constrictions and presents the importance of critical salt concentration, critical ionic strength for mixed salt, critical shear stressor critical particle concentration and consequently their role on contaminant transport in porous media.

460 citations

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TL;DR: This review emphasizes the importance of costs in industrial-scale treatment of dye wastewater and provides a way to assess the cost-based feasibility of bio-adsorption technologies and discusses the major factors affecting adsorption and desorption performance based on basic chemical and physical structures ofBio-adsorbents available in literatures.

353 citations