Biodiversity of mycotoxigenic fungi and their secondary metabolites in sugarcane juice

Sugarcane juice is a traditional beverage consumed on a daily basis, by millions of people, in different countries such as Brazil, Egypt, India and Pakistan. Detection of mycotoxigenic fungi in sugarcane fields has been documented, however, very little is known about mycotoxin contamination in the other sugarcane-based products, especially sugarcane juice (1). The current study investigated the co-contamination of several mycotoxins (AFB1, AFB2, AFG1, AFG2, DAS, DON, FB1, FB2, FB3, OTA, STERIG, T-2, and ZEN). Further, a polyphasic approach was applied in order to identify and classify the isolated fungal species (2). Mycotoxin contamination results have been used to estimate the dietary exposure of the Egyptian population to mycotoxins through juice consumption. Samples (n=89) were randomly collected from local vendors and juice shops during two seasons (summer 2016 and winter 2017) from Assiut City, Upper Egypt. Extraction and quantification of mycotoxins were performed by liquid-liquid extraction followed by a validated UPLC-MS/MS analytical method. Morphological and molecular identification of mycotoxigenic fungi and other microorganisms was performed according to Samson et al., 2010 (2). Dereplication strategy was also applied to unravel the diversity of the produced secondary metabolites using an in-house screening library with a fast DDA UHPLC–TOF-MS profiling method that can screen for hundreds of mycotoxins and other metabolites. Risk assessment of mycotoxins using probabilistic and deterministic approaches at various scenarios for adult male and female Egyptian juice consumers was performed. So far the obtained results for the targeted analysis, exhibit the contamination of sugarcane juice samples with AFB1 and FB1 mycotoxins in 63% (n=56) of the samples. Juice collected during winter had a contamination range of 0.1-3 µg.L−1 for AFB1 and 4-58 µg.L−1 for FB1, while samples from the summer season had a contamination range of 0.3-1.3 µg.L−1 for AFB1 only. Furthermore, the risk assessment using probabilistic and deterministic approaches for adult male and female Egyptian juice consumers pinpointed a remarkable difference in levels of exposure to mycotoxins between the two seasons and between males & females. Other results will be presented during the workshop. Figure 1:- Proposed workflow to determine the commonly occurring mycotoxins in sugarcane juice. Food Frequency Questionnaires will be used to collect data for juice consumption in Egypt that will be used to conduct risk assessment studies. An untargeted approach will be used to screen and identify the unknown fungal secondary metabolites. References 1. Abdallah MF, Krska R, Sulyok M (2016). Mycotoxin Contamination in Sugarcane Grass and Juice: First Report on Detection of Multiple Mycotoxins and Exposure Assessment for Aflatoxins B₁ and G₁ in Humans. 2. Samson RA, Houbraken J, Thrane U, et al. (2010). Food and indoor fungi. CBS KNAW Biodiversity Center, Utrecht.