Agro-Environmental Research Centre, Institute of Environmental Sciences, Hungarian University of Agriculture and Life Sciences, Páter Károly u. 1, 2100, Gödöllő, Hungary.
Food and Wine Research Institute, Eszterházy Károly Catholic University, Leányka u. 6, 3300, Eger, Hungary.
Appl Microbiol Biotechnol. 2024 May 29;108(1):348. doi: 10.1007/s00253-024-13190-7.
Mycotoxin production by aflatoxin B1 (AFB1) -producing Aspergillus flavus Zt41 and sterigmatocystin (ST) -hyperproducer Aspergillus creber 2663 mold strains on corn and rice starch, both of high purity and nearly identical amylose-amylopectin composition, as the only source of carbon, was studied. Scanning electron microscopy revealed average starch particle sizes of 4.54 ± 0.635 µm and 10.9 ± 2.78 µm, corresponding to surface area to volume ratios of 127 1/µm for rice starch and 0.49 1/µm for corn starch. Thus, a 2.5-fold difference in particle size correlated to a larger, 259-fold difference in surface area. To allow starch, a water-absorbing powder, to be used as a sole food source for Aspergillus strains, a special glass bead system was applied. AFB1 production of A. flavus Zt41 was determined to be 437.6 ± 128.4 ng/g and 90.0 ± 44.8 ng/g on rice and corn starch, respectively, while corresponding ST production levels by A. creber 2663 were 72.8 ± 10.0 µg/g and 26.8 ± 11.6 µg/g, indicating 3-fivefold higher mycotoxin levels on rice starch than on corn starch as sole carbon and energy sources. KEY POINTS: • A glass bead system ensuring the flow of air when studying powders was developed. • AFB1 and ST production of A. flavus and A. creber on rice and corn starches were studied. • 3-fivefold higher mycotoxin levels on rice starch than on corn starch were detected.
以高纯度且几乎具有相同直链淀粉-支链淀粉组成的玉米淀粉和大米淀粉为唯一碳源，研究了产黄曲霉毒素 B1（AFB1）的黄曲霉 Zt41 和产麦角固醇的赭曲霉 2663 霉菌菌株在这两种淀粉上的产毒情况。扫描电子显微镜显示，淀粉颗粒的平均粒径分别为 4.54±0.635μm 和 10.9±2.78μm，相应的比表面积与体积比分别为大米淀粉的 127 1/μm 和玉米淀粉的 0.49 1/μm。因此，粒径相差 2.5 倍，比表面积相差 259 倍。为了使能吸水的淀粉粉末能够被曲霉用作唯一的食物来源，应用了一种特殊的玻璃珠系统。确定黄曲霉 Zt41 在大米淀粉和玉米淀粉上的 AFB1 产量分别为 437.6±128.4ng/g 和 90.0±44.8ng/g，而赭曲霉 2663 的相应 ST 产量分别为 72.8±10.0µg/g 和 26.8±11.6µg/g，这表明作为唯一的碳源和能源，大米淀粉上的霉菌毒素水平比玉米淀粉高 3-5 倍。要点：• 开发了一种确保粉末在研究时空气流通的玻璃珠系统。• 研究了黄曲霉和赭曲霉在大米淀粉和玉米淀粉上的 AFB1 和 ST 产量。• 在大米淀粉上检测到比在玉米淀粉上高 3-5 倍的霉菌毒素水平。
