Kuvempu University

About: Kuvempu University is a education organization based out in Shimoga, India. It is known for research contribution in the topics: Cyclic voltammetry & Carbon paste electrode. The organization has 1575 authors who have published 2210 publications receiving 39755 citations. The organization is also known as: KU.

Development of multi-walled carbon nanotubes modified pencil graphite electrode for the electrochemical investigation of aceclofenac present in pharmaceutical and biological samples

Abstract: A sensitive and novel chemically modified multi-walled carbon nanotubes modified pencil graphite electrode (MCPGE) has been developed for the electrochemical investigation of aceclofenac (ACF). MCPGE was characterized by scanning electron microscopy (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Phosphate buffer solution (PBS) of pH 7.0 was used as a suitable electrolytic medium, in which aceclofenac (ACF) exhibited a sensitive adsorption controlled oxidation peaks at + 0.12, + 0.32 and + 0.51 V and a reduction peak at − 0.26 V (vs Ag/AgCl). The experimental conditions were optimised by means of investigating the dependence of peak current on solution pH, concentration and scan rate etc. The electrochemical parameters such as surface concentration (Γ), electron transfer coefficient (α) and the standard rate constant (ks) were investigated at MCPGE. The oxidative peak currents were varied linearly with concentration in the range between 1 × 10− 6 to 60 × 10− 6 M with a detection limit of 2.6 × 10− 9 M. The UV–Vis absorption spectrum of ACF gave the λmax at 272–273 nm and is attributed to the presence of ACF. The applicability of the MCPGE was illustrated by the determination of ACF present in pharmaceutical and human urine samples.

Biodegradation of Natural Rubber by Laccase and Manganese Peroxidase Enzyme of Bacillus subtilis

Abstract: The present study was carried out to isolate rubber degrading bacteria and to check the enzymes responsible for degradation, so that the isolates can be effectively used in rubber degradation. Different bacteria were isolated from soil samples and natural rubber samples collected from a rubber processing unit, and were screened for their ability to degrade natural rubber by plate assay. A biodegradation experiment was carried out in the laboratory to confirm degradation. Enzymes responsible for natural rubber degradation were characterized, crude enzyme was extracted by submerged fermentation process and its activity was determined. After extraction of crude enzyme, it was partially purified by dialysis process, and then, the enzyme activity and specific activity were determined. Then, the ability of these enzymes to degrade natural rubber discs were checked. The ability of natural rubber degrading microorganisms to degrade rubber products such as rubber gloves discs and rubber tire discs, was tested. Among the isolated bacterial species, Bacillus subtilis was predominant and showed growth on the natural rubber discs. The biodegradation experiment showed 48.6 % weight loss. It was screened that laccase and manganese peroxidase enzymes are responsible for natural rubber degradation. When enzyme activity was determined, Bacillus subtilis, showed more manganese peroxidase activity compared to laccase activity. Laccase enzyme activity was 0.0138 IU and manganese peroxidase activity was 0.0155 IU. The molecular weights of laccase enzyme (64 kDa) and of manganese peroxidase enzyme (68 kDa) were determined. Biodegradation of rubber by microorganisms was confirmed by Schiff’s staining, SEM, FTIR and NMR studies.

Corrosion inhibition behavior of Ketosulfone for Zinc in acidic medium

Abstract: The corrosion inhibition behavior of Ketosulfone for zinc is investigated by polarization and AC-impedance techniques at 303-333K. The Tafel plots indicates that the Ketosulfone is a mixed type inhibitor. The interaction between metal and inhibitor is explained by Langmuir adsorption isotherm. DG 0 ads andDH 0 ads value indicates the electrostatic interactions between metal and inhibitor. Calculated activation parameters explains the corrosion process. SEM images show the difference between inhibited solutions and blank solution.