Development and Application of an Indirect Competitive Enzyme-Linked Immunoassay for Aflatoxin M1 in Milk and Milk-Based Confectionery

Devi, K T and Mayo, M A and Hall, A J and Craufurd, P Q and Wheeler, T R and Waliyar, F and Subramanyam, A and Reddy, D V R (2000) Development and Application of an Indirect Competitive Enzyme-Linked Immunoassay for Aflatoxin M1 in Milk and Milk-Based Confectionery. Journal of Agriculture and Food Chemistry, 50. pp. 933-937. ISSN 0021-8561

PDF - Published Version Restricted to ICRISAT users only Download (60kB) | Request a copy

Abstract

High-titer rabbit polyclonal antibodies to aflatoxin M1 (AFM1) were produced by utilizing AFM1- bovine serum albumin (BSA) conjugate as an immunogen. An indirect competitive enzyme-linked immunosorbent assay was standardized for estimating AFM1 in milk and milk products. To avoid the influence of interfering substances present in the milk samples, it was necessary to prepare AFM1 standards in methanol extracts of certified reference material (CRM) not containing detectable AFM1 (<0.05 ng/g). The reliability of the procedure was assessed by using CRM with AFM1 concentrations of <0.5 and 0.76 ng/g. Also, assays of milk samples mixed with AFM1 ranging in concentration between 0.5 and 50 ng/L gave recoveries of >93%. The relative cross-reactivity with aflatoxins (AF) and ochratoxin A, assessed as the amount of AFM1 necessary to cause 50% inhibition of binding, was 5% for AFB1 and much less for AFB2, AFG1, and AFG2; there was no reaction with ochratoxin A. AFM1 contamination was measured in retail milk and milk products collected from rural and periurban areas in Andhra Pradesh, India. Of 280 milk samples tested, 146 were found to contain <0.5 ng/mL of AFM1; in 80 samples it varied from 0.6 to 15 ng/mL, in 42 samples from 16 to 30 ng/mL, and in 12 samples from 31 to 48 ng/mL. Most of the milk samples that contained high AFM1 concentrations were obtained from periurban locations. The results revealed a significant exposure of humans to AFM1 levels in India and thus highlight the need for awareness of risk among milk producers and consumers.

Item Type:	Article
Divisions:	UNSPECIFIED
CRP:	UNSPECIFIED
Uncontrolled Keywords:	Aflatoxin M1, antibodies, ELISA, milk, milk-based confectionery
Subjects:	Mandate crops > Groundnut Others > Food and Nutrition
Depositing User:	Mr Sanat Kumar Behera
Date Deposited:	20 Oct 2011 07:53
Last Modified:	20 Oct 2011 07:53
URI:	http://oar.icrisat.org/id/eprint/2984
Official URL:
Projects:	UNSPECIFIED
Funders:	UNSPECIFIED
Acknowledgement:	We thank Y. Ramachandraiah for technical assistance.
Links:	Author

View Statistics

Actions (login required)

View Item