Lopez-Diaz T M, Flannigan B
International Centre for Brewing and Distilling, Heriot-Watt University, Riccarton, Edinburgh, UK.
Int J Food Microbiol. 1997 Apr 1;35(2):129-36. doi: 10.1016/s0168-1605(96)01211-1.
Production of patulin and cytochalasin E by four strains of Aspergillus clavatus during small-scale laboratory malting of barley at 16 and 25 degrees C was investigated. Fungal biomass, measured as ergosterol, appeared to be greater at 25 than at 16 degrees C, but marked differences were observed between the degree of colonization by the different strains. Patulin was detected in extracts by HPLC. Net production was greater at 16 degrees C, but amounts were strain dependent. Except for one strain, cytochalasin E was detected only in barley malted at 25 degrees C. In experiments with wheat inoculated with two A. clavatus strains, ergosterol levels in the green malts were generally greater than in corresponding barley malts. Patulin was again detected in all samples, with the equivalent of 22.4 mg/kg being detected in one sample at 16 degrees C, but cytochalasin E was only found at 25 degrees C, the highest level detected being 13.8 mg/kg. In samples of barley spiked with toxin and kilned at 80 degrees C for 24 h, only about one-fifth of the amount of toxin recovered from corresponding unkilned controls was detected. It is indicated that differences in both contaminant strains and temperature in different maltings may account for disparities between symptoms reported for individual outbreaks of mycotoxicosis associated with malting by-products.
研究了4株棒曲霉在16℃和25℃下对大麦进行小规模实验室制麦过程中展青霉素和细胞松弛素E的产生情况。以麦角固醇衡量的真菌生物量在25℃时似乎比在16℃时更大，但不同菌株的定殖程度存在显著差异。通过高效液相色谱法在提取物中检测到了展青霉素。净产量在16℃时更高，但产量因菌株而异。除了一个菌株外，仅在25℃制麦的大麦中检测到细胞松弛素E。在用两株棒曲霉接种小麦的实验中，绿麦芽中的麦角固醇水平通常高于相应的大麦麦芽。在所有样品中再次检测到展青霉素，在一个16℃的样品中检测到相当于22.4 mg/kg的展青霉素，但细胞松弛素E仅在25℃时被发现，检测到的最高水平为13.8 mg/kg。在添加毒素并在80℃下烘烤24小时的大麦样品中，从相应未烘烤对照中回收的毒素量仅检测到约五分之一。结果表明，不同制麦过程中污染菌株和温度的差异可能是与制麦副产品相关的个别霉菌毒素中毒暴发报告症状之间差异的原因。
