A portable, disposable, and low-cost optode for sulphide and thiol detection

Ellman's reagent-based optode for sulphides and tihiols.

Determination of cysteamine in animal feeds by high performance liquid chromatography with diode-array detection (HPLC-DAD)

A HPLC-DAD method for the determination of cysteamine supplementation in commercial animal feeds was developed. Samples were extracted with a mixture of 0.5 % hydrochloric acid – acetonitrile (90:10, v/v), matrix interferences were removed with a C18 cartridge, cysteamine was derivatized using 5,5'-dithiobis-(2-nitrobenzoic) acid (DTNB) as Ellman's reagent targeting to the thiol group in the molecule. Quantification of cysteamine was performed on a c18 column with DAD at 323 nm. The developed method had LOD of 1.1 mg/l, good linearity of the calibration curve (R2 ≥ 0.9998), high recoveries (> 92 %), and high reproducibility (RSD < 2.0%).

AcetylcholinesteraseInhibition by Biofumigant (Coumaran) from Leaves ofLantana camarain Stored Grain and Household Insect Pests

Recent studies proved that the biofumigants could be an alternative to chemical fumigants against stored grain insect pests. For this reason, it is necessary to understand the mode of action of biofumigants. In the present study the prospectus of utilisingLantana camaraas a potent fumigant insecticide is being discussed. Inhibition of acetylcholinesterase (AChE) by Coumaran, an active ingredient extracted from the plantL. camara, was studied. The biofumigant was used as an enzyme inhibitor and acetylthiocholine iodide as a substrate along with Ellman’s reagent to carry out the reactions. Thein vivoinhibition was observed in both dose dependent and time dependent in case of housefly, and the nervous tissue (ganglion) and the whole insect homogenate of stored grain insect exposed to Coumaran. The possible mode of action of Coumaran as anacetylcholinesteraseinhibitor is discussed.