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The ability of cinnamon, clove, lemon grass, oregano and palmarosa essential oils to prevent growth of and fumonisin B1 (FB1) production by Fusarium verticillioides at different water activity (0.95 and 0.995 aw) and temperature (20 and 30 °C) levels in irradiated maize grain was evaluated. All the essential oils inhibited growth of F verticillioides isolates under all conditions tested, but FB1 production was only inhibited at 30 °C and 0.995 aw. Moreover, stimulation of toxin production was found under certain environmental conditions. None of the essential oils showed a significantly greater ability to inhibit FB1 production when compared with the others. At 1000 mg essential oil kg?1 maize the essential oils showed a greater inhibitory effect on growth of F verticillioides than at 500 mg kg?1, but there was no difference in FB1 production between the two levels of essential oil. Copyright © 2004 Society of Chemical Industry  相似文献   

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The aim of this study was to apply RP-HPLC/ESI-ITMS and RP-HPLC/ESI-TOFMS to investigate and characterise six new higher molecular weight fumonisins (three pairs of isomers) extracted from a Fusarium verticillioides-infected solid rice culture. The ITMS and ITMS2 spectra clearly indicated the m/z values (960, 984 and 986) of the protonated molecules and the FB1 toxin-like structures of these compounds, respectively. Moreover, the data evaluation software of the TOFMS equipment unambiguously demonstrated the exact masses of the protonated molecules and the suggested empirical formulae (C50H89NO16, C52H89NO16 and C52H91NO16) of the new fumonisins, with mass accuracy in the range between 0.1 and ?1.1?ppm. Subtraction of the empirical formula of FB1 toxin (C34H59NO15) from these formulae and correction for the mass of water split-off from the fumonisin molecule during ester formation resulted in the empirical formulae of the fumonisin backbone esterifying agents (fatty acids): C16H32O2 (palmitic acid, PA), C18H32O2 (linoleic acid, LA) and C18H34O2 (oleic acid, OA). We denoted the new compounds as esterified FB1 (EFB1) toxins, with the suggested names EFB1 PA, iso-EFB1 PA, EFB1 LA, iso-EFB1 LA, EFB1 OA and iso-EFB1 OA. The total amount of these new compounds comprised 0.1% of the FB1 concentration, which may be rated as significant when it is considered that these new components are significantly more apolar than earlier-described fumonisins, and their uptake into and toxicity elicited in the various tissues of living organisms may therefore also be significantly different from those of other fumonisins.  相似文献   

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The impact on fungal growth and mycotoxin formation of interactions between fumonisin‐producing isolates of Fusarium moniliforme and F proliferatum and a zearalenone (ZEA)‐ and deoxynivalenol (DON)‐producing isolate of F graminearum inoculated together on irradiated maize at 15 and 25 °C and at 0.98, 0.95 and 0.93 aw was studied. The presence of F graminearum decreased the fungal populations (CFU g−1 grain) of F moniliforme and F proliferatum under almost all conditions tested. In the presence of F moniliforme, CFUs of F graminearum increased significantly at 25 °C, especially at 0.93 and 0.95 aw, while the presence of F proliferatum caused them to increase at 15 °C. The presence of F graminearum always inhibited FB1 production, except at 25 °C and 0.98 aw where it increased. However, the observed differences were not statistically significant. There was no effect of fungal interaction on ZEA production by F graminearum; however, when paired with F moniliforme and F proliferatum, DON production by F graminearum was significantly stimulated, especially at 0.98 aw. © 2000 Society of Chemical Industry  相似文献   

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目的 综合比较伏马毒素4种柱前衍生[邻苯二甲醛(OPA)、萘-2,3-二甲醛(NDA)、丹磺酰氯、6-氨基喹啉-N-羟基琥珀酰亚胺氨基甲酸酯(AQC)]效果的优劣, 并选择一种衍生剂用于玉米样品中伏马毒素B1(FB1)、B2(FB2)、B3(FB3)的检测, 建立柱前衍生-超高压液相色谱法同时测定玉米中伏马毒素B1、B2和B3的方法。方法 采用乙腈-水(50∶50, v/v)溶液提取玉米中的伏马毒素B1、B2和B3, 涡旋震荡及离子交换柱净化对玉米样品中的伏马毒素B1、B2和B3进行提取与净化, 经衍生后进行超高压液相色谱-荧光检测器检测。 结果 最终选择OPA衍生作为本研究的衍生方法。3种伏马毒素的线性范围分别为50~1000 ng/mL、25~500 ng/mL、25~500 ng/mL, 相关系数R2均大于0.999; 最低定量限LOQ分别为25.0、14.0、17.0 μg/kg; 3个浓度的加标回收率分别为(75.6?1.6)%~(83.4?2.3)%, (78.9?5.4)%~(90.0?0.7)%, (83.7?8.2)%~(88.6?1.0)%; FB1、FB2和FB3的日间精密度分别为3.62%、3.41%、4.77%。结论 该方法具有预处理简单、检测速度快、灵敏度高的优点, 可满足对玉米中>800 μg/kg伏马毒素含量的检测要求。流动相的改进及梯度洗脱的使用, 提高了检测的灵敏度, 并可被在具有液相色谱仪的实验室应用。  相似文献   

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