Marine sponge-associated bacteria as a potential source for polyhydroxyalkanoates

Sathiyanarayanan, Ganesan,Saibaba, Ganesan,Kiran, George Seghal,Yang, Yung-Hun,Selvin, Joseph Informa UK (Taylor Francis) 2017 Critical reviews in microbiology Vol.43 No.3

1H NMR Based Metabolomics Studies of the Toxicity of Titanium Dioxide Nanoparticles in Zebrafish (Danio rerio)

Ganesan Raja,김시원,윤다혜,윤창신,김석만 대한화학회 2018 Bulletin of the Korean Chemical Society Vol.39 No.1

Titanium dioxide nanoparticles (TiO2-NPs) are widely used in foods, cosmetics, and pharmaceuticals. In the present study, male and female zebrafish (Danio rerio) were exposed to sub-lethal concentrations of TiO2-NPs dosed at 0.1 mg/L (low) and 5.0 mg/L (high), respectively. 1H–nuclear magnetic resonance (NMR) profiling combined with univariate and multivariate statistics was used to assess metabolic alterations in the TiO2-NP-treated fish. Purine metabolism—including the anabolism/catabolism of ATP, ADP, AMP, xanthine, and inosine—was significantly influenced, which may indicate some genotoxicity resulting from TiO2-NP exposure. Increasing the dose and duration of TiO2-NP exposure led to additional metabolic disturbances in glycerophospholipid metabolism and the Krebs cycle. Our findings demonstrate the potential applicability of using a metabolomics approach to determine underlying metabolic disturbances caused by TiO2-NPs.

Hierarchical Ni_3.5Co_5.5S₈ nanosheet-assembled hollow nanocages: Superior electrocatalyst towards oxygen evolution reaction

Ganesan, Vinoth,Ramasamy, Parthiban,Kim, Jinkwon Elsevier 2017 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY - Vol.42 No.9

<P><B>Abstract</B></P> <P>Developing highly efficient and cost-effective electrocatalysts for oxygen evolution reaction (OER) is crucial for renewable energy storage technologies. Here, we synthesized hierarchical Co-based bimetallic sulfide nanostructures as an efficient electrocatalyst for OER. Ni<SUB>3.5</SUB>Co<SUB>5.5</SUB>S<SUB>8</SUB> nanostructures were synthesized by solvothermal sulfurization and thermal annealing of pre-synthesized homogenous bimetallic metal–organic frameworks (MOFs). Electron microscopy studies revealed that the Ni<SUB>3.5</SUB>Co<SUB>5.5</SUB>S<SUB>8</SUB> has hollow nanocage like morphology with thin nanosheets grown on the surface. In addition, Co<SUB>9</SUB>S<SUB>8</SUB> hollow nanocages were also synthesized for comparative electrocatalytic evaluation with the Ni<SUB>3.5</SUB>Co<SUB>5.5</SUB>S<SUB>8</SUB> nanosheet-assembled hollow nanocages (NAHNs). The Ni<SUB>3.5</SUB>Co<SUB>5.5</SUB>S<SUB>8</SUB> NAHNs has exhibited a low overpotential of 333 mV at the current density of 10 mA cm<SUP>−2</SUP> (1.563 V <I>vs</I> RHE) and Tafel slope of 48.5 mV dec<SUP>−1</SUP> for the oxygen evolution reaction in 1 M KOH. Benefitting from their structural merits, Ni<SUB>3.5</SUB>Co<SUB>5.5</SUB>S<SUB>8</SUB> NAHNs manifest excellent OER electrocatalytic activity compared to most of the recently reported non-precious catalyst for OER.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Hierarchical Ni<SUB>3.5</SUB>Co<SUB>5.5</SUB>S<SUB>8</SUB> nanosheet assembled hollow nanocages (NAHNs) were successfully synthesized. </LI> <LI> Ni<SUB>3.5</SUB>Co<SUB>5.5</SUB>S<SUB>8</SUB> NAHNs provide high porous nature and large surface area. </LI> <LI> Explored as efficient, low potential electrocatalyst to drive the oxygen evolution reaction. </LI> <LI> Ni<SUB>3.5</SUB>Co<SUB>5.5</SUB>S<SUB>8</SUB> NAHNs catalyst exhibited better OER stability. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Inexpensive electrochemical synthesis of nickel iron sulphides on nickel foam: super active and ultra-durable electrocatalysts for alkaline electrolyte membrane water electrolysis

Ganesan, P.,Sivanantham, A.,Shanmugam, S. Royal Society of Chemistry 2016 Journal of materials chemistry. A, Materials for e Vol.4 No.42

<P>Efficient and durable electrocatalysts for water splitting (both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER)) are required for the replacement of expensive noble metal-based catalysts used in water electrolysis devices. Herein, we describe the inexpensive synthesis of electrochemically deposited nickel iron sulphides on nickel foam (NiFeS/NF) and their use as highly efficient bi-functional water splitting catalysts that can meet the current energy demands. The NiFeS/NF electrocatalysts exhibited low overpotentials of approximately 231 mV for the OER and 180 mV for the HER in 1 M KOH. Moreover, the NiFeS/NF electrocatalysts exhibited a turnover frequency of one order of magnitude higher than those of state-of-the-art noble metal catalysts (RuO2 and Pt/C) for the OER and HER. In addition to this excellent activity, the bi-functional catalyst also exhibited an outstanding OER and HER electrode stability for over 200 h with minimal loss in activity. Further, it can be directly used in the practical application of alkaline electrolyte membrane water electrolysis. The high performance, prolonged electrode stability, and facile synthesis as an adherent coating on nickel foam suggest that NiFeS/NF electrocatalysts might be suitable for use as alternative commercially viable catalysts.</P>

Characterization of uncertainties in atmospheric trace gas inversions using hierarchical Bayesian methods

Ganesan, A. L.,Rigby, M.,Zammit-Mangion, A.,Manning, A. J.,Prinn, R. G.,Fraser, P. J.,Harth, C. M.,Kim, K.-R.,Krummel, P. B.,Li, S.,Mü,hle, J.,O&,apos,Doherty, S. J.,Park, S.,Salameh, P. K.,Ste Copernicus GmbH 2014 Atmospheric chemistry and physics Vol.14 No.8

<P>Abstract. We present a hierarchical Bayesian method for atmospheric trace gas inversions. This method is used to estimate emissions of trace gases as well as 'hyper-parameters' that characterize the probability density functions (PDFs) of the a priori emissions and model-measurement covariances. By exploring the space of 'uncertainties in uncertainties', we show that the hierarchical method results in a more complete estimation of emissions and their uncertainties than traditional Bayesian inversions, which rely heavily on expert judgment. We present an analysis that shows the effect of including hyper-parameters, which are themselves informed by the data, and show that this method can serve to reduce the effect of errors in assumptions made about the a priori emissions and model-measurement uncertainties. We then apply this method to the estimation of sulfur hexafluoride (SF6) emissions over 2012 for the regions surrounding four Advanced Global Atmospheric Gases Experiment (AGAGE) stations. We find that improper accounting of model representation uncertainties, in particular, can lead to the derivation of emissions and associated uncertainties that are unrealistic and show that those derived using the hierarchical method are likely to be more representative of the true uncertainties in the system. We demonstrate through this SF6 case study that this method is less sensitive to outliers in the data and to subjective assumptions about a priori emissions and model-measurement uncertainties than traditional methods. </P>

CoS₂-TiO₂ hybrid nanostructures: efficient and durable bifunctional electrocatalysts for alkaline electrolyte membrane water electrolyzers

Ganesan, Pandian,Sivanantham, Arumugam,Shanmugam, Sangaraju The Royal Society of Chemistry 2018 Journal of Materials Chemistry A Vol.6 No.3

<P>The development of efficient catalysts to overcome the significant overpotential of the oxygen evolution reaction (OER) is the key bottleneck in the large-scale production of pure hydrogen. In the present work, we describe a simple approach for the fabrication of CoS2-TiO2 hybrid catalysts by the heat treatment of a cobalt thiourea complex in the presence of TiO2. We show the CoS2-TiO2 hybrid as a bi-functional electrocatalyst for overall water splitting in alkaline electrolyte membrane water electrolyzers. The optimal CoS2-TiO2 hybrid offered low overpotentials of 231 and 198 mV for the OER and HER, respectively. Fundamental studies pertaining to the role of TiO2 in enhancing the catalytic activity of the materials using optical and electrochemical band gap measurements of the CoS2-TiO2 hybrids were carried out. Additionally, the constructed MEA using the CoS2-TiO2 hybrid showed higher performance with an approximately 234 mA cm<SUP>−2</SUP> current density at a cell voltage of 1.9 V and exhibited extended durable operation over 200 h, as compared to the MEA constructed with state-of-the-art all-noble-metal electrodes.</P>

Hyper-Cross-Linked Porous Porphyrin Aluminum(III) Tetracarbonylcobaltate as a Highly Active Heterogeneous Bimetallic Catalyst for the Ring-Expansion Carbonylation of Epoxides

Ganesan, Vinothkumar,Yoon, Sungho American Chemical Society 2019 ACS APPLIED MATERIALS & INTERFACES Vol.11 No.20

<P>Development of an industrially viable catalyst for the ring-expansion carbonylation of epoxides remains challenging in the view of facile product separation and recyclability. Herein, we report a heterogenized porous porphyrin Al(III) tetracarbonylcobaltate bimetallic catalyst for the ring-expansion carbonylation of epoxides. The catalyst was synthesized using a hyper-cross-linking strategy involving methylene bridges introduced by the Friedel-Crafts reaction and incorporated with cobaltate anions. The catalyst effectively converts epoxides into the corresponding β-lactones with an excellent site time yield of 360 h<SUP>-1</SUP>, which is comparable to that of the corresponding homogeneous catalysts and is the highest of any heterogeneous catalyst reported so far for this reaction.</P> [FIG OMISSION]</BR>

RCC frames with ferrocement and fiber reinforced concrete infill panels under reverse cyclic loading

Ganesan, N.,Indira, P.V.,Irshad, P. Techno-Press 2017 Advances in concrete construction Vol.5 No.3

An experimental investigation was carried out to study the strength and behavior of reinforced cement concrete (RCC) frames with ferrocement and fiber reinforced concrete infill panel. Seven numbers of $1/4^{th}$ scaled down model of one bay-three storey frames were tested under reverse cyclic loading. Ferrocement infilled frames and fiber reinforced concrete infilled frames with varying volume fraction of reinforcement in infill panels viz; 0.20%, 0.30%, and 0.40% were tested and compared with the bare frame. The experimental results indicate that the strength, stiffness and energy dissipation capacity of infilled frames were considerably improved when compared with the bare frame. In the case of infilled frames with equal volume fraction of reinforcement in infill panels, the strength and stiffness of frames with fiber reinforced concrete infill panels were slightly higher than those with ferrocement infill panels. Increase in volume fraction of reinforcement in the infill panels exhibited only marginal improvement in the strength and behavior of the infilled frames.

Maillard Reaction of Pidan White as Inhibited by Chinese Black Tea Extract (Camellia sinensis) in the Pickling Solution

Ganesan, Palanivel,Benjakul, Soottawat,Baharin, Badlishah Sham Korean Society for Food Science of Animal Resource 2014 한국축산식품학회지 Vol.34 No.4

Changes in Maillard reaction of pidan white were monitored with $A_{294}$, fluorescence intensity, and browning intensity during pickling in the absence and presence of Chinese black tea extract (Camellia sinensis) at levels of 2% and 5% together with 0.2% $ZnCl_2$ or 0.2% $CaCl_2$ up to 3 wk, followed by ageing for another 3 wk. Browning intensity and $A_{294}$ of pidan white increased with increasing pickling/ageing, while fluorescence intensity decreased during ageing (p<0.05), irrespective of treatments. At wk 6, pidan white treated with 0.2% $ZnCl_2$ and 0.2% $CaCl_2$ showed slightly higher browning intensity, fluorescence intensity and $A_{294}$ than those treated with divalents together with Chinese black tea (p<0.05). Free amino group and sugar contents showed continuous decrease during pickling and ageing irrespective of tea and cations used. However, pidan treated without Chinese black tea extract showed significantly lower free amino group and sugar during the ageing of 6 wk (p<0.05). Thus, Chinese black tea extract had an inhibitory effect on the Maillard reaction during ageing of pidan white.

Nephroprotective effect of Sphaeranthus amaranthoides Burm f.: Sivakaranthai (a Siddha Kayakalpa drug) against gentamicin induced nephrotoxicity

Ganesan Rethinam,Anand Duraiswamy,G. Dayanand Reddy,P. Elankani,Sampath Kundrapakkam Srinivasan 경희대학교 융합한의과학연구소 2022 Oriental Pharmacy and Experimental Medicine Vol.22 No.2

Acute kidney injury (AKI) is described as a disorder with a sudden loss of kidney function. AKI is also attributed to several aetiologies such as diabetes, cardiac problems, etc. Developing a therapy for AKI is challenging due to its complex pathophysiology. The present study investigated the effect of Sphaeranthus amaranthoides Burm f. aqueous extract, a Siddha Kalpha drug, against gentamicin-induced AKI. Animals were initially pre-administered with different concentrations of S. amaranthoides and later induced with gentamicin on the 8th day. Biochemical, anti-inflammatory and antioxidant markers were analysed. Further, HRLCMS analysis was carried out to identify the bioactive components. Components including myo-inositol, traumatic acid, rosmarinic acid, etc. were identified. In the animals induced with gentamicin, KIM1, LDH, GGT, creatinine, BUN and electrolytes were elevated in both serum and urine, while noted within normal range in S. amaranthoides pre-administered groups. Histopathology analysis revealed prevention of necrosis, tubular epithelial cell degeneration and glomerular congestion in S. amaranthoides administered animals. Lipid peroxidation, KIM1, Cystatin C, TNFα, IL6 and NFκB were within normal range in tissues. Thus, it is evident that S. amaranthoides is effective in protecting kidney damage and treating AKI. Further studies will be conducted to analyse the pathways resurrecting kidney damage.