Identification of Fusarium oxysporum Fungus in Wheat Based on Chemical Markers and Qualitative GC-MS Test

Abstract

Fusarium oxysporum is usually found in foods such as corn, wheat, soybeans and barley, and can cause economic losses and risks to health in humans and animals due to the production of mycotoxins. The conventional microbiological test for fungal identification is based on morphological characteristics, requires specialists, and it is very time-consuming as it is necessary to carry out a culture of the fungus for two weeks before microorganism identification. Nowadays, researchers have made efforts to develop alternative analytical methods with advantages such as shorter time of analysis and better accuracy and reproducibility when compared to microbiological methods. In this way, in the present work, a qualitative analytical method to detect the secondary metabolites of Fusarium oxysporum in culture media by gas chromatography coupled to mass spectrometry (GC-MS) was developed with the intention of relating the presence of these chemical compounds to contamination by the fungus. The method comprised liquid-liquid or liquid-solid extractions with ethyl acetate from liquid and solid culture media, respectively, followed by GC-MS analysis, which was able to identify the presence of fusaric acid, 13-socosenamide, 5-(4-hydroxybutyl)-2-pyridinecarboxylic acid and toxin HT-2. The presence of these compounds was confirmed by high-performance liquid chromatography coupled to mass spectrometry quadrupole time of flight (HPLC-MS/QTOF).

Advances in Chemical and Biological Methods to Identify Microorganisms—From Past to Present

“…With the advancements observed in MS methods, along with new data analysis, and processing and visualization tools, our understanding of biological systems has also increased, since we could analyze diverse sets of biomolecules, such as proteins, lipids, carbohydrates, and amino acids [53,54,55,56,57]. Several ionization and separation techniques can be coupled with MS, such as gas chromatography (GC) [52,58,59,60,61], matrix-assisted laser desorption ionization time-of-flight mode (MALDI-TOF) [62,63,64,65,66,67,68], electromigration techniques [37,69], and electrospray ionization (ESI) [70,71].…”

Mass Spectrometry: A Rosetta Stone to Learn How Fungi Interact and Talk

“…Exploratory analysis of VOCs emitted by fungi typically involves a headspace analysis of in vitro cultures. VOCs-based biotyping has been used to identify species of Candida [93,94,98], Penicillium [123], Fusarium [124] and Rhizoctonia [125]. This type of biotyping can employ headspace absorptive extraction techniques associated with gas chromatography-time flight mass spectrometry (GC-TOF-MS) or liquid-liquid extraction methods associated with gas chromatography-mass spectrometry electron ionization (GC-MS-EI).…”