Llorens Amparo, Mateo Rufino, Hinojo Maria J, Logrieco Antonio, Jimenez Misericordia
Departamento de Microbiología y Ecologia, Facultad de Biologia, Universidad de Valencia, Burjassot, Valencia, Spain.
Syst Appl Microbiol. 2004 Mar;27(2):253-60. doi: 10.1078/072320204322881871.
To carry out the physiological characterization of Fusarium graminearum and F. culmorum isolates with regard to its zearalenone producing ability, an in-depth experiment with a full factorial design was conducted. The effects and mutual interactions of temperature, moisture, substrate and isolate on the production of the toxin were studied. The study was done with twelve isolates of Fusarium (7 of F. graminearum and 5 of F. culmorum). The analysis of variance shows that there is a complex interaction of all of these factors, which can influence the relative concentrations of the mycotoxin produced, and hence, the correct physiological characterization of the strain. All the tested cultures were susceptible to invasion by Fusarium. The moisture content of grains (water activity values 0.960, 0.970 and 0.980) did not constitute a limiting factor for fungal growth or ZEA production, but incubation temperature (15 degrees C, 20 degrees C, 28 degrees C, and 32 degrees C) affected the rate of zearalenone synthesis. Very low or undetectable ZEA production was observed at 32 degrees C. All tested isolates showed a characteristic behavior concerning the optimum temperature for ZEA production, which was usually 20 degrees C maintained during the whole incubation period. This finding, which does not agree with other reports obtained with strains from different origins, suggests that there are genetic differences that would explain the particular physiological behavior of each isolate related to the optimal production conditions for ZEA. The existence of significant differences regarding the susceptibility of the assayed cereal grains (wheat, corn and rice) used for ZEA production by the different Fusarium species (F. graminearum and F. culmorum) is described for the first time in this paper.
为了对禾谷镰刀菌和黄色镰刀菌分离株的玉米赤霉烯酮产生能力进行生理特性分析，开展了一项采用全因子设计的深入实验。研究了温度、湿度、底物和分离株对毒素产生的影响及相互作用。该研究使用了12株镰刀菌分离株（7株禾谷镰刀菌和5株黄色镰刀菌）。方差分析表明，所有这些因素之间存在复杂的相互作用，这会影响所产生霉菌毒素的相对浓度，进而影响菌株正确的生理特性。所有测试培养物都易受镰刀菌侵染。谷物的水分含量（水分活度值0.960、0.970和0.980）并非真菌生长或玉米赤霉烯酮产生的限制因素，但培养温度（15℃、20℃、28℃和32℃）会影响玉米赤霉烯酮的合成速率。在32℃时观察到极低或未检测到玉米赤霉烯酮产生。所有测试分离株在玉米赤霉烯酮产生的最佳温度方面均表现出特征性行为，整个培养期间的最佳温度通常为20℃。这一发现与来自不同来源菌株的其他报告不一致，表明存在遗传差异，可以解释每个分离株与玉米赤霉烯酮最佳生产条件相关的特定生理行为。本文首次描述了不同镰刀菌物种（禾谷镰刀菌和黄色镰刀菌）用于玉米赤霉烯酮生产的受试谷物（小麦、玉米和水稻）在易感性方面存在显著差异。
