Yin Hsin-Bai, Chen Chi-Hung, Kollanoor-Johny Anup, Darre Michael J, Venkitanarayanan Kumar
Department of Animal Science, 3636 Horsebarn Hill Rd Ext., Unit 4040, University of Connecticut, Storrs, Connecticut, CT 06269, USA.
Department of Animal Science, University of Minnesota, St. Paul, Minnesota, MN 55108, USA.
Poult Sci. 2015 Sep;94(9):2183-90. doi: 10.3382/ps/pev207. Epub 2015 Jul 27.
Aflatoxins (AF) are toxic metabolites primarily produced by molds, Aspergillus flavus and Aspergillus parasiticus. Contamination of poultry feed with AF is a major concern to the poultry industry due to severe economic losses stemming from poor performance, reduced egg production, and diminished egg hatchability. This study investigated the inhibitory effect of 2 generally regarded as safe (GRAS), natural plant compounds, namely carvacrol (CR) and trans-cinnamaldehyde (TC), on A. flavus and A. parasiticus growth and AF production in potato dextrose broth (PDB) and in poultry feed. In broth culture, PDB supplemented with CR (0%, 0.02%, 0.04% and 0.08%) or TC (0%, 0.005%, 0.01% and 0.02%) was inoculated with A. flavus or A. parasiticus (6 log CFU/mL), and mold counts and AF production were determined on days 0, 1, 3, and 5. Similarly, 200 g portions of poultry feed supplemented with CR or TC (0%, 0.4%, 0.8%, and 1.0%) were inoculated with each mold, and their counts and AF concentrations in the feed were determined at 0, 1, 2, 3, 4, 8, and 12 weeks of storage. Moreover, the effect of CR and TC on the expression of AF synthesis genes in A. flavus and A. parasiticus (aflC, nor1, norA, and ver1) was determined using real-time quantitative PCR (RT-qPCR). All experiments had duplicate samples and were replicated 3 times. Results indicated that CR and TC reduced A. flavus and A. parasiticus growth and AF production in broth culture and chicken feed (P<0.05). All tested concentrations of CR and TC decreased AF production in broth culture and chicken feed by at least 60% when compared to controls (P<0.05). In addition, CR and TC down-regulated the expression of major genes associated with AF synthesis in the molds (P<0.05). Results suggest the potential use of CR and TC as feed additives to control AF contamination in poultry feed.
黄曲霉毒素（AF）是主要由黄曲霉和寄生曲霉等霉菌产生的有毒代谢产物。由于家禽生长性能不佳、产蛋量减少以及孵化率降低导致严重经济损失，家禽饲料被AF污染是家禽行业的一个主要担忧。本研究调查了两种一般认为安全（GRAS）的天然植物化合物，即香芹酚（CR）和反式肉桂醛（TC），对黄曲霉和寄生曲霉在马铃薯葡萄糖肉汤（PDB）以及家禽饲料中的生长和AF产生的抑制作用。在肉汤培养中，向添加了CR（0%、0.02%、0.04%和0.08%）或TC（0%、0.005%、0.01%和0.02%）的PDB中接种黄曲霉或寄生曲霉（6 log CFU/mL），并在第0、1、3和5天测定霉菌数量和AF产量。同样，向添加了CR或TC（0%、0.4%、0.8%和1.0%）的200 g家禽饲料部分接种每种霉菌，并在储存0、1、2、3、4、8和12周时测定饲料中的霉菌数量和AF浓度。此外，使用实时定量PCR（RT-qPCR）测定CR和TC对黄曲霉和寄生曲霉中AF合成基因（aflC、nor1、norA和ver1）表达的影响。所有实验均有重复样本且重复3次。结果表明，CR和TC降低了肉汤培养和鸡饲料中黄曲霉和寄生曲霉的生长以及AF产生（P<0.05）。与对照相比，所有测试浓度的CR和TC使肉汤培养和鸡饲料中的AF产量至少降低了60%（P<0.05）。此外，CR和TC下调了霉菌中与AF合成相关的主要基因的表达（P<0.05）。结果表明CR和TC作为饲料添加剂控制家禽饲料中AF污染的潜在用途。
