Toxigenic potentiality of Aspergillus flavus and Aspergillus parasiticus strains isolated from black pepper assessed by an LC-MS/MS based multi-mycotoxin method.
A liquid chromatography triple quadrupole tandem mass spectrometry method was developed and validated to determine mycotoxins, produced by fungal isolates grown on malt extract agar (MEA). All twenty metabolites produced by different fungal species were extracted using acetonitrile/1% formic acid. The developed method was applied to assess the toxigenic potentiality of Aspergillus flavus (n = 11) and Aspergillus parasiticus (n = 6) strains isolated from black peppers (Piper nigrum L.) following their growth at 22, 30 and 37 °C. Highest mean radial colony growth rates were observed at 30 °C for A. flavus (5.21 ± 0.68 mm/day) and A. parasiticus (4.97 ± 0.33 mm/day). All of the A. flavus isolates produced aflatoxin B1 and O-methyl sterigmatocystin (OMST) while 91% produced aflatoxin B2 (AFB2) and 82% of them produced sterigmatocystin (STERIG) at 30 °C. Except one, all the A. parasiticus isolates produced all the four aflatoxins, STERIG and OMST at 30 °C. Remarkably high AFB1 was produced by some A. flavus isolates at 22 °C (max 16-40 mg/kg). Production of mycotoxins followed a different trend than that of growth rate of both species. Notable correlations were found between different secondary metabolites of both species; R(2) 0.87 between AFB1 and AFB2 production. Occurrence of OMST could be used as a predictor for AFB1 production.
NutriFOODchem Unit, Department of Food Safety and Food Quality (Partner in Food2Know), Faculty of Bioscience Engineering, Ghent University, Belgium; Laboratory of Food Analysis, Department of Bioanalysis (Partner in Food2Know), Faculty of Pharmaceutical Sciences, Ghent University, Belgium. Electronic address: Pratheeba.Yogendrarajah@UGent.be.
Pratheeba
P
Yogendrarajah
Laboratory of Food Microbiology and Food Preservation, Department of Food Safety and Food Quality (Partner in Food2Know), Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000, Ghent, Belgium.
Frank
F
Devlieghere
Laboratory of Food Analysis, Department of Bioanalysis (Partner in Food2Know), Faculty of Pharmaceutical Sciences, Ghent University, Belgium.
Emmanuel
E
Njumbe Ediage
Laboratory of Food Microbiology and Food Preservation, Department of Food Safety and Food Quality (Partner in Food2Know), Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000, Ghent, Belgium.
Liesbeth
L
Jacxsens
NutriFOODchem Unit, Department of Food Safety and Food Quality (Partner in Food2Know), Faculty of Bioscience Engineering, Ghent University, Belgium.
Bruno
B
De Meulenaer
Laboratory of Food Analysis, Department of Bioanalysis (Partner in Food2Know), Faculty of Pharmaceutical Sciences, Ghent University, Belgium.
Sarah
S
De Saeger
D001230:Aspergillus / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D001231:Aspergillus flavus / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D009183:Mycotoxins / Q000737:chemistry* / Q000378:metabolism; D029222:Piper nigrum / Q000382:microbiology*; D053719:Tandem Mass Spectrometry / Q000379:methods*
D009183:Mycotoxins
Aflatoxins; Aspergillus flavus; Aspergillus parasiticus; LC-MS/MS; Malt extract agar; O-methyl sterigmatocystin