Detoxification of Aflatoxin B1 by Zygosaccharomyces rouxii with Solid State Fermentation in Peanut Meal

Abstract

Aflatoxins are highly carcinogenic, teratogenetic, and morbigenous secondary metabolites of Aspergillus flavus and A. parasiticus that can contaminate multiple staple foods, such as peanut, maize, and tree nuts. In this study, Zygosaccharomyces rouxii was screened out and identified from fermented soy paste-one kind of traditional Chinese food-to detoxify aflatoxin B 1 (AFB 1 ) by aerobic solid state fermentation in peanut meal. The optimal degradation condition was chosen from single factor experiment, and the most effective detoxification rate was about 97%. As for liquid fermentation, we tested the binding ability of Z. rouxii, and the highest binding rate reached was 74.3% (nonviable cells of Z. rouxii) in phosphate-buffered saline (PBS). Moreover, the biotransformation of AFB 1 through fermentation of Z. rouxii in peanut meal was further verified by liquid chromatography/mass spectrometry (LC/MS). According to TIC scan, after fermentation by Z. rouxii, the AFB 1 in peanut meal was prominently degraded to the lowering peaks of AFB 1 . Additionally, m/s statistics demonstrated that AFB 1 may be degraded to some new products whose structural properties may be different from AFB 1 , or the degradation products may be dissolved in the aqueous phase rather than the organic phase. As far as we know, this is the first report indicating that the safe strain of Z. rouxii has the ability to detoxify AFB 1 .

Degradation of Aflatoxin B1 and Zearalenone by Bacterial and Fungal Laccases in Presence of Structurally Defined Chemicals and Complex Natural Mediators

“…Being produced by the Aspergilli species including Aspergillus flavus , Aspergillus nomius , and Aspergillus parasiticus [3], aflatoxins cause an economical loss of $1.68 billion in the United States annually [4]. There are more than 20 types of aflatoxins including AFB 1 , AFB 2 , AFG 1 , and AFG 2 , among which AFB 1 is the most toxic, causing severe liver damage [5]. Zearalenone (ZEN), a mycotoxin with estrogenic potency [6] causing swelling of the vulva and infertility in swine [7], is instead produced by the Fusarium species, such as Fusarium graminearum and Fusarium culmorum [8].…”

Fusion expression and anti-Aspergillus flavusactivity of a novel inhibitory protein DN-AflR

“…AFB 1 was analyzed according to retention time in HPLC system equipped with a ZORBAX Eclipse XDB-C18 column (4.6×150 mm, 5um, Agilent, Palo Alto, CA, USA) and a 470 fluorescent detector (G1321A, Agilent, USA) (λexc 360 nm; λem 440 nm) using a mobile phase solvent of 10% acetonitrile, 40% methanol, and 50% water. The flow rate was 0.8 ml min −1 and injection volume was 20 μl (25).…”

A Focus on Aflatoxins in Feedstuffs: Levels of Contamination, Prevalence, Control Strategies, and Impacts on Animal Health

“…Zygosaccharomyces rouxii from fermented soy paste [138]. The authors demonstrated nonviable cell binding and biotransformation of AFB 1 in which reduction was monitored by LC/MS.…”