Mousavi Seyyed Amin Ayatollahi, Pourtalebi Somayyeh
Department of Medical Mycology and Parasitology, School of Medicine, Kerman University of Medical Science, Kerman, Iran.
Department of Microbiology, School of Medicine, Rafsanjan University of Medical Sciences, Rafsanjan, Iran.
Iran J Med Sci. 2015 Nov;40(6):501-6.
Aflatoxins (AFs) are secondary hazardous fungal metabolites that are produced by strains of some Aspergillus species on food and feedstuffs. Aflatoxin B1 (AFB1) is one of the most important AF with high toxicity. Prevention of AF production and their elimination from food products is a matter of importance for many researchers in the last decades. Nanomaterials applications in medical science have been widely studied in the recent years. Most of existing researches seek the effect of nanoparticles on bacteria, fungi, and viruses. The aim of this study was to determine the effects of silver nanoparticles (AgNPs) on growth and AFB1 production of AF-producing Aspergillus parasiticus.
A parasiticus was inoculated (10(6) conidia per ml of medium) to potato dextrose broth (PDB) medium and then AgNPs was added and incubated with shaking at 130 rpm and 28°C for 7 days. AF was assayed by high performance liquid chromatography (HPLC). Microbiological assay (MBA) on microplates contained potato dextrose broth (PDB) medium (4 days at 28°C) at different concentrations of AgNPs (60, 80, 100, 120, 140, 160, 180 and 200 μg/ml) was measured.
The results demonstrated that a minimum inhibition concentration (MIC) equal to 180 μg/ml was determined for AgNPs against A. parasiticus. The AgNPs effectively inhibited AFB1 production at a concentration of 90 μg/ml.
The results obtained in this study show AgNPs at concentrations lower than the MIC drastically inhibited production of AFB1 by A. parasiticus in culture medium. The AgNPs may be useful to control AF contamination of susceptible crops in the field.
黄曲霉毒素（AFs）是由某些曲霉菌株在食品和饲料上产生的次生有害真菌代谢产物。黄曲霉毒素B1（AFB1）是毒性最强的重要黄曲霉毒素之一。在过去几十年中，预防黄曲霉毒素的产生并从食品中消除它们是许多研究人员关注的重要问题。近年来，纳米材料在医学领域的应用得到了广泛研究。现有的大多数研究都在探寻纳米颗粒对细菌、真菌和病毒的影响。本研究的目的是确定银纳米颗粒（AgNPs）对产AF的寄生曲霉生长和AFB1产生的影响。
将寄生曲霉接种到马铃薯葡萄糖肉汤（PDB）培养基中（每毫升培养基接种10⁶个分生孢子），然后加入AgNPs，并在130 rpm和28°C下振荡培养7天。通过高效液相色谱法（HPLC）测定AF。在含有不同浓度AgNPs（60、80、100、120、140、160、180和200 μg/ml）的马铃薯葡萄糖肉汤（PDB）培养基微孔板上进行微生物测定（MBA）（在28°C下培养4天）。
结果表明，AgNPs对寄生曲霉的最低抑菌浓度（MIC）为180 μg/ml。AgNPs在90 μg/ml的浓度下能有效抑制AFB1的产生。
本研究结果表明，浓度低于MIC的AgNPs能显著抑制培养基中寄生曲霉产生AFB1。AgNPs可能有助于控制田间易感作物的AF污染。
