PJB-2023-565
Detection of aflatoxigenic Aspergilli and estimation of aflatoxins in edible oil available in Karachi.
shaista Fatima
Abstract
Fungi and their toxic secondary metabolites cause serious health problems for living beings. Among these secondary metabolites, aflatoxins in food and feed items are a serious burden to the economy. Thus, the identification of aflatoxigenic Aspergilli found in edible oil and detection of total aflatoxins (AFs) was carried out. Thirty edible oil samples were collected from different local markets of Karachi, tested for the presence of A. flavus and aflatoxin levels. Out of thirty samples, only four samples were positive for A. flavus by culture-based method which were further verified by amplification of the partial ITS region. AFs production was observed by color change techniques in which all A. flavus positive isolates JB2, MGM4, LMM1, and RLM2, turned plum red color after exposing them to ammonium hydroxide vapors on Sabouraud Dextrose Agar (SDA) plates while only one sample JB2 showed color change on Yeast Extract Sucrose (YES) and Coconut Agar Medium (CAM). Only one sample JB2 displayed blue fluorescence on the coconut agar medium plate under UV light (positive for aflatoxins). AFs were then extracted from edible oil samples by solvent extraction method. Total AFs were estimated by fluorescence detection using VICAM fluorometer. Among the samples collected, one sample had total aflatoxin between 20-30 ppb, 5 samples had total aflatoxin of < 20 ppb while 24 samples were negative for aflatoxin. It was concluded that cultural, molecular and analytical techniques could be collectively used for rapid detection and identification of aflatoxins and aflatoxigenic fungi.
To Cite this article:
Download
