Achar P N, Hermetz K, Rao S, Apkarian R, Taylor J
Department of Biology and Physics, Kennesaw State University, Kennesaw, GA 30144, USA.
Ecotoxicol Environ Saf. 2009 Nov;72(8):2115-20. doi: 10.1016/j.ecoenv.2009.04.002. Epub 2009 May 14.
This article describes the use of microscopy to prove the presence of the aflatoxin producing pathogen, Aspergillus flavus Link ex Fries in commercially available edible peanuts in Georgia. Light microscopy in combination with electron microscopy has been used to describe the infection course established by the fungus. The alkali maceration technique used in the study was successful and sufficient to detect the kernel infection of A. flavus and monitor the infection percentage in edible peanuts. Percentage of infected kernel varied from one commercial outlet to another in the region. Briefly, peanut seeds from Cartersville had the highest percentage of A. flavus infection. Electron microscopy confirmed the seed-borne infection of this mold. Mycelium established inside the host tissues both intercellularly and intracellularly aided by active, continuous branching of young hyphae. Establishment of mycelium was also detected in the xylem vessels of roots indicative of systemic infection. Thus, edible peanuts can form an important source of inoculum and facilitate the spread of the fungus from one peanut to another in commercial outlets and elsewhere. Present study provides strong evidence that A. flavus can escape detection at selling points and lands in commercial outlets via edible peanuts. That these contaminated peanuts could pose public health hazards is discussed.
本文描述了利用显微镜技术来证实黄曲霉毒素产生病原体——弗里斯链格孢菌（Aspergillus flavus Link ex Fries）在佐治亚州市售食用花生中的存在情况。光学显微镜与电子显微镜相结合已被用于描述该真菌所建立的感染过程。研究中使用的碱浸技术是成功且足以检测黄曲霉对果仁的感染并监测食用花生中的感染率的。该地区不同商业销售点的受感染果仁百分比各不相同。简而言之，卡特斯维尔的花生种子黄曲霉感染率最高。电子显微镜证实了这种霉菌通过种子传播感染。在活跃且持续分支的幼嫩菌丝的辅助下，菌丝在宿主组织内细胞间和细胞内形成。在根部的木质部导管中也检测到了菌丝的形成，这表明存在系统性感染。因此，食用花生可成为接种体的重要来源，并促进该真菌在商业销售点及其他地方从一颗花生传播到另一颗花生。本研究提供了有力证据，证明黄曲霉可在销售点逃过检测，并通过食用花生进入商业销售点。文中还讨论了这些受污染的花生可能对公众健康造成危害的情况。
