RESEARCH JOURNAL OF PURE SCIENCE AND TECHNOLOGY (RJPST )

E-ISSN 2579-0536
P-ISSN 2695-2696
VOL. 6 NO. 3 2023
DOI: https://doi.org/10.56201/rjpst.v6.no3.2023.pg131.141


Spectrophotometric Determination of Carbaryl Residues in Vegetables Using Crude Peroxidase from Wheat Bran

A.M Magomya and A.M Ago


Abstract


A spectrophotometric method for the determination of carbaryl based on the catalytic reaction of peroxidase enzyme is presented. The method involves the alkaline hydrolysis of carbaryl into 1-naphthol followed by enzymatic reaction with peroxidase in the presence of 4- aminoantipyrine and hydrogen peroxide to yield a red-coloured product which is measured at 502 nm. Wheat bran was exploited as a source of peroxidase in this study and the enzyme was extracted by a simple method without any purification. Parameters influencing the enzyme assay activity such as concentrations of NaOH, hydrogen peroxide, 4-aminoantipyrine, pH and incubation time were investigated and optimized. Under optimized conditions, absorbance of the system was found to be proportional to carbaryl concentration in the range of 0.5– 2.5 mg L ?1 with R 2 value of 0.987. Limit of detection (LOD) and limit of quantitation (LOQ) for the system were 0.22 mg L ?1 and 0.67 mg L ?1 respectively. Application of the method to the determination of carbaryl residues in spiked vegetable samples revealed good recoveries ranging from 86 - 118 %. Relative standard deviation (RSD) for intraday measurements (n=7) were 4.25 % and 2.72 % for 0.5 and 1 mg/L concentration respectively. Overall, the investigated method showed good sensitivity and selectivity for the quantitative analysis of residual carbaryl.


Carbaryl, Peroxidase, 1-naphtol, Enzyme, Spectrphotometry


References:


Ahmad, Q., Mehmood, A., Saeed, Z., & Fayyaz, M., (2019). Purification and
Characterization of Peroxidase from Broccoli (Brassica oleracea l. Var. Italica)
Stems. Electronic J Biol, 15 (1):38-45

Caetano,J., Sergio A.S. & Machado, (2008). Determination of carbaryl in tomato “in
natura” using an amperometric biosensor based on the inhibition of
acetylcholinesterase activity, Sensors and Actuators B: Chemical, 129(1): 40-46

Didpinrum, P., Ponhong, K., Siriangkhawut, W., Supharoek, S. & Grudpan, K. (2019). A
cost-effective spectrophotometric method based on enzymatic analysis of jackfruit


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