Vázquez B I, Fente C, Franco C M, Quinto E, Cepeda A, Prognon P
Departamento de Química Analítica, Nutrición y Bromatología, Facultad de Veterinaria, Universidad de Santiago de Compostela, Lugo, Spain.
Lett Appl Microbiol. 1997 May;24(5):397-400. doi: 10.1046/j.1472-765x.1997.00148.x.
A new rapid semi-quantitative fluorimetric assay for citrinin production testing in mould cultures has been developed. The chemical structure of the citrinin makes it a weak native fluorophore. This fluorescence can be strongly enhanced in an acidic environment. A standard curve where the concentration of HCl needed to show the yellow fluorescence signal of different concentrations of citrinin was established, thus providing a semi-quantitative method to prove the capacity of toxin production of fungal cultures. Two Penicillium strains from the Spanish National Collection of Type Cultures, were studied for the toxin production on YES broth at 25 degrees C for 21 d. The culture was assayed daily for the presence/absence and quantification of citrinin by adding the HCl concentration set, and also quantified by RP-HPLC as a confirmation procedure. Experiments demonstrate that 5 d are necessary to show the presence of citrinin. As an illustration, a total of 48 strains of Penicillium isolated from cheese and cheese factories were analysed with the proposed method.
已开发出一种用于霉菌培养物中桔青霉素产生量检测的新型快速半定量荧光测定法。桔青霉素的化学结构使其成为一种弱天然荧光团。在酸性环境中，这种荧光可被强烈增强。建立了一条标准曲线，该曲线表示不同浓度桔青霉素显示黄色荧光信号所需的盐酸浓度，从而提供了一种半定量方法来证明真菌培养物产生毒素的能力。对来自西班牙国家典型培养物保藏中心的两株青霉菌株，在25℃的YES肉汤中培养21天，研究其毒素产生情况。每天通过加入设定的盐酸浓度来检测培养物中桔青霉素的存在与否及进行定量，同时也通过反相高效液相色谱法进行定量作为确认程序。实验表明，需要5天才能检测到桔青霉素的存在。作为例证，用所提出的方法对从奶酪和奶酪工厂分离出的总共48株青霉菌株进行了分析。
