[关键词]
[摘要]
目的 研究远志加工过程中4种黄曲霉毒素B1、B2、G1、G2(AFB1、ATB2、AFG1、AFG2)的污染情况以及污染真菌的类群及变化,分析黄曲霉毒素的主要污染途径。方法 对远志采收、加工过程的21份样品,利用免疫亲和柱-HPLC柱后光化学衍生法测定黄曲霉毒素含量,通过稀释平板法分离污染真菌,结合形态学和分子生物学特征对菌株进行鉴定。结果 有15份远志样品检出黄曲霉毒素,但均未超出《中国药典》2015年版中AFB1、黄曲霉毒素总量的限量标准,阳性样品分布在每个生产环节。新采收的远志根上真菌总数在堆放发汗后升高,新鲜去木质心的远志筒上真菌总数达到2.0×108 CFU/g以上,晾晒干燥后有所降低;直接干燥的远志棍上真菌总数在加工过程中变化不大;真菌总数与药材水活度呈显著正相关。分离鉴定的209株真菌归属到5个属,青霉属Penicillium为所有加工环节样品上的优势属,堆放发汗过程中枝孢属Cladosporium和镰刀菌属Fusarium数量明显增加,加工后的晾晒过程曲霉属Aspergillus真菌明显增加。获得的1株寄生曲霉Aspergillus parasiticus可以产AFB1、AFB2、AFG1和AFG2。结论 田间生产和采后加工都有可能造成远志黄曲霉毒素污染,青霉菌大量污染有可能带来的毒素问题需要引起重视。
[Key word]
[Abstract]
Objective To investigate aflatoxins contamination B1、B2、G1、G2 (AFB1、ATB2、AFG1、AFG2), toxigenic fungi species and potential contamination sources of Polygalae Radix during post-harvest processing, and analyze the main ways of aflatoxins contamination. Methods Twenty-one Polygalae Radix samples were collected from multiple steps during the post-harvest processing in this study. Aflatoxin levels in these samples were determined by immunoaffinity column and HPLC coupled with post-column photochemical derivatization. Dilution-plate method was applied for the fungi isolation followed by strain identification based on morphological characterization and molecular approaches. Results Aflatoxins were detected in 15 samples, but none of them exceeded the limit set by Chinese Pharmacopoeia. The fungal counts increased significantly from newly harvested samples to post-sweating, and the counts further increased to the maximum (2×108 CFU/g) after xylem-removing, then decreased after drying. In contrast, fungal counts of samples dried directly after harvesting did not change much throughout the processing. There was a significant positive correlation between fungal counts and water activity (Aw). A total of 209 fungal belonged to five genera were identified from the samples, and Penicillium was the predominant genus. Cladosporium and Fusarium were increased after sweating, and then Aspergillus increased after xylem-removing and drying. One A. parasiticus strain was confirmed to be able to produce AFB1, AFB2, AFG1, and AFG2. Conclusion Aflatoxins contamination happened in both field production and post-harvest processing of Polygalae Radix. Especially, the contamination of Penicillium spp. should be paid more attention.
[中图分类号]
R282.2
[基金项目]
国家中药标准化项目(ZYBZH-Y-JIN-34);国家自然科学基金资助项目(81274071)