小麦籽粒中原型及修饰型脱氧雪腐镰刀菌烯醇的产生规律研究

Production of free and modified forms of deoxynivalenol in wheat grain

中文关键词:  禾谷镰刀菌  小麦籽粒  脱氧雪腐镰刀菌烯醇  乙酰化脱氧雪腐镰刀菌烯醇  脱氧雪腐镰刀菌烯醇-3-葡萄糖苷

英文关键词:Fusarium graminearum  wheat grain  deoxynivalenol  acetyl-deoxynivalenol  deoxynivalenol-3- glucoside

中文摘要:

      目的 研究原型脱氧雪腐镰刀菌烯醇(deoxynivalenol, DON)及其修饰型的产生规律。方法 以小麦籽粒为培养材料, 辐照灭菌后接种禾谷镰刀菌, 并分别在不同温度(10、20、30 ℃)和水活度(0.95、0.98 aw)下培养不同时间(7、14、21、28、35 d)后, 运用超高效液相色谱-串联质谱检测DON, 3-乙酰化脱氧雪腐镰刀菌烯醇(3-acetyl-deoxynivalenol, 3-ADON), 15-乙酰化脱氧雪腐镰刀菌烯醇(15-acetyl-deoxynivalenol, 15-ADON)和脱氧雪腐镰刀菌烯醇-3-葡萄糖苷(deoxynivalenol-3-glucoside, D3G)的产量。结果 在所有培养条件下, 原型DON的产量均随时间延长而增加; 并于0.98 aw, 20 ℃下的第35 d达到最高值100490.0 μg/kg; 不同培养条件下, 修饰型DON的生成情况各不相同, 3-ADON、15-ADON和D3G分别于0.98 aw, 20 ℃下的第14、28和 35 d达到各自产量最高值(3-ADON: 7583.5 μg/kg; 15-ADON: 592.0 μg/kg; D3G: 6806.4 μg/kg)。此外, 10 ℃下, D3G/DON比值随时间延长先增高后降低, 而20、30 ℃下D3G/DON比值随时间延长呈指数下降(r2>0.90)。结论 小麦籽粒中原型和修饰型DON的最适产生条件均为0.98 aw, 20 ℃。本研究可为DON及其修饰型的生物合成、日常监管、污染防控等提供理论基础和科学依据。

英文摘要:

      Objective To investigate the production mechanisms of free and modified forms of deoxynivalenol (DON). Methods Irradiated wheat grains were inoculated artificially with Fusarium graminearum and then incubated at different temperatures (10, 20, 30 ℃) and water activities (0.95, 0.98 aw). After incubation of 7, 14, 21, 28 and 35 days, the production of DON, its modified forms of 3-acetyl-deoxynivalenol (3-ADON), 15-acetyl-deoxynivalenol (15-ADON) and DON-3-glucoside (D3G), were quantified by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Results DON contents increased gradually in time dependent manner in all conditions, and the highest yield was 100490.0 μg/kg on day 35 at 20 ℃ and 0.98 aw. However, the highest yields of 3-ADON, 15-ADON and D3G were observed on day 24, 18 and 35 at 20 ℃ and 0.98 aw (3-ADON: 7583.5 μg/kg; 15-ADON: 592.0 μg/kg; D3G: 6806.4 μg/kg), respectively. In addition, the ratio of D3G/DON increased firstly and then decreased at 10 ℃, and declined gradually at 20 ℃ and 30 ℃, which could be well described by exponential model (r2>0.90). Conclusion The optimum temperature for free and modified forms of DON production was 20 ℃ and the optimum water activity was 0.98 aw. Our results could provide theoretical base and scientific foundation for biosynthesis, routine supervision, prevention and control of free and modified DON.