Meta-analytic review on the impact of temperature and water activity in deoxynivalenol synthesis by Fusarium graminearum

Abstract

Deoxynivalenol (DON) is a mycotoxin produced by Fusarium species, causing involuntary regurgitation in animals including humans. Some studies showed that its synthesis is influenced by environmental factors such as temperature and water activity (a w ). This article presents a meta-analysis of two major studies on the phenomenon, discussing on what should be expected in future research in this direction. The specimens were cultured in maize and wheat. In all experiments, Fusarium graminearum was incubated at 15 o C, 22 o C, 25 o C, 28 o C and 30 o C. At room temperature, the water activity was set to 0.95, 0.97, 0.99, and 0.995. Then, levels of DON were quantified weekly since the 14th day until the 49th day, using HPLC with UV detector at 220 nm. Temperature and water activity seem to have an impact on DON synthesis, though the true correlations still require further analysis.

Fusarium graminearum Colors and Deoxynivalenol Synthesis at Different Water Activity

“…This result contrasts with some found in the literature showing significant differences between DON concentrations at distinct a w [7,8,9]. Though it is difficult to know why these results were counterintuitive, it might have been due to chemical, genetic (distinct strains) or nutritional differences [10]. All other experiments were performed with irradiated wheat, while the current was carried out with YEA.…”

“…Water activity (a w ) is among the environmental factors with impact on the quantity of DON produced by Fusarium graminearum (teleomorph: Gibberella zeae ) [7,8,9]. Though there are still some inconsistences on how they are related, increased a w seems to favor higher DON production [10]. According to Leplat, et al [11], at 25 °C F. graminearum a w tolerance is between 0.9 and 0.995, being the optimal range between 0.95 and 0.995 (higher a w values are not mentioned).…”

<em>Fusarium graminearum</em> Colors and Deoxynivalenol Synthesis at Different Water Activity

“…This result contrasts with some found in the literature showing significant differences between DON concentrations at distinct aw [3][4][5]. Though it is difficult to know why these results were counterintuitive, it might have been due to chemical, genetic (distinct strains) or nutritional differences [6]. All other experiments were performed with irradiated wheat, while the current was carried out with YEA.…”

Why RGB Imaging Should be Used to Analyze Fusarium Graminearum Growth and Estimate Deoxynivalenol Contamination

“…Considerable parts of the experiment have been published in journal articles [8,26,38,39,40] and conferences [41,42]. There are two unpublished works still under peer review, one of them with a preprint [43].…”

“…These molds have garnered attention from researchers, scholars and legislators because of their deleterious impact in agriculture, trade, health and animal sciences. The most commonly found in temperate areas are F. graminearum and F. moniliforme , sometimes F. culmorum , F. proliferatum , F. equiseti , F. sporotrichoids and F. poae [8,9,10]. F. graminearum is perhaps the main mold responsible for Fusarium head blight (FHB) in crops such as oats ( Avena sativa ), rice ( Oryza sativa ) and other cereals [5].…”