# Occurrence of Filamentous Fungi and Mycotoxins in Fresh and Minimally Processed Leafy Vegetables from Gardens and Markets

## TL;DR

This study found that leafy vegetables often contain harmful fungi and mycotoxins, which could pose health risks to consumers.

## Contribution

The study identifies specific fungal genera and mycotoxin contamination in fresh and minimally processed leafy vegetables.

## Key findings

- Filamentous fungi concentrations were 9.4 × 10² CFU/g in fresh vegetables and 3.4 × 10² CFU/g in minimally processed vegetables.
- Cladosporium, Alternaria, and Fusarium were the most frequently identified fungal genera.
- Spinach samples showed the highest percentage of zearalenone contamination.

## Abstract

Fresh, minimally processed foods contain many valuable nutrients but are also a source of pathogenic microorganisms. This study aimed to investigate the presence of filamentous fungi and mycotoxin contamination in leafy vegetables. A total of 160 samples of lettuce, spinach, mixed salads, and sprouts from markets and gardens were tested. Fungal strains were cultured on Malt Extract Agar with chloramphenicol (50 mg/L). Fungal identification was performed by macroscopic and microscopic observations, amplification of the small subunit rRNA (SSU rRNA) gene fragment, and sequencing. Total aflatoxins, aflatoxin B1, and zearalenone contents were determined using the ELISA method. The mean concentrations of filamentous fungi in fresh and minimally processed vegetables were 9.4 × 102 CFU/g and 3.4 × 102 CFU/g, respectively. Nineteen fungal genera were identified, in addition to non-sporulating fungi, of which the largest percentage comprised the genera Cladosporium (38%), Alternaria (37%), and Fusarium (30%), and less frequently Penicillium, Mucor, Trichoderma, and Aspergillus (from 8 to 14% of positive samples). The highest percentage of samples contaminated with zearalenone was observed in the spinach group. Ready-to-eat leafy vegetables should be monitored for contamination with filamentous fungi and mycotoxins as they pose a potential risk to consumer health.