中文摘要：本研究旨在确定近红外光谱(NIRS)作为一种诊断黄曲霉毒素污染的工具的价值，特别是快速定性或定量预测玉米黄曲霉毒素的水平方面。研究表明，大约有18%的污染玉米样品会被接受，而28%的优质玉米会被丢弃或宣布污染或降级，这些假阳性和假阴性值使得使用NIRS的信心不足。不过，这种定标可用于育种计划，不需要湿化学分析，只需半定量分等。
外文摘要：The aim of this study is to determine the value of near-infrared spectroscopy (NIRS) as a diagnostic tool for aflatoxin contamination, specifically to rapidly predict levels of aflatoxin, either quantitatively or qualitatively, in ground maize. Maize was collected from inoculated field trials conducted across four sites in Kenya. Inoculated and uninoculated maize ears were harvested, milled, and prepared for NIRS scanning and wet chemistry-based aflatoxin quantification. Several statistical and machine learning techniques were compared. Absorbance at a single bandwidth explained 34% of the variation in levels of aflatoxin using a regression model while a partial least-squares (PLS) method showed that NIR measurements could explain 42% of the variation in aflatoxin levels. To compare various methods for their ability to classify samples with high (>100 ppb) levels of aflatoxin, various additional procedures were applied. The k-nearest neighbour classification method yielded sensitivity and specificity values of 0.75 and 0.52 respectively, compared with the support vector machine method with estimates of 0.81 and 0.68, whereas PLS could achieve values of 0.82 and 0.72 respectively. The corresponding false positive and false negative values are still unacceptable for NIRS to be used with confidence, as similar to 18% of contaminated ground maize samples would be accepted and 28% of good maize would be discarded or declared contaminated or downgraded. However, such calibrations could be useful in breeding programs without access to wet chemistry analysis, seeking to rank entries semiquantitatively.
作者：Darnell, RE；Harvey, JJ；Fox, GP；Fletcher, MT；Wainaina, J；Wanjuki, I；Turner, WJ
作者单位：CSIRO
期刊名称：AUSTRALIAN JOURNAL OF CHEMISTRY
期刊影响因子：1.427
出版年份：2018
出版刊次：11
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