紫外分光光度法测定黑曲霉发酵液中糠醛的含量

Determination of Furfural in Aspergillusniger Fermentation Broth by Ultraviolet Spectrophotometry

本文建立了一种利用紫外分光光度法测定黑曲霉(Aspergillusniger)发酵液中糠醛含量的方法。首先对糠醛标准溶液全波长扫描,确定糠醛最大吸收波长,并作为糠醛含量的测定波长。测量糠醛工作液吸光度,绘制糠醛浓度与吸光度关系的标准曲线。制备黑曲霉发酵液,用50%乙醇将发酵母液稀释10倍,测定波长下测定吸光度,参照标准曲线计算发酵液中糠醛的含量。结果表明糠醛的最大吸收波长为276nm,即为测定波长;糠醛标准曲线线性回归方程:y=0. 164x+0. 001,R2=0. 999,测定范围内线性良好;发酵液糠醛含量30. 0244μg/ml;精密度RSD值为0. 315%,仪器精密度良好;稳定性RSD值0. 450%,待测样品在120 min内稳定;重现性RSD值0. 828%,试验方法具有良好重现性;回收率为99. 12%～100. 35%,其RSD值0. 617%。本方法操作易掌握、测定快速、稳定性好且仪器设备成本较低,有利于基础研究和推广。为今后研究黑曲霉其他次生代谢物含量提供了一定方法和数据的参考。

A method for determination of furfural content in the fermentation broth of Aspergillusniger van Tieghem （Fungi： Eurotiales：Trichocomaceae）was developed by ultraviolet （UV） spectrophotometry. The maximum absorption wavelength of furfural was first determined by the full-wavelength scan of furfural standard solution, and then used as measurement wavelength of furfural content. The absorbance of furfural working broth was measured and the standard curve of the relationship between furfural concentration and absorbance was drawn. The fermentation broth of Aspergillusniger was prepared. The mother broth of fermentation was diluted 10 times with 50 % ethanol. The absorbance was determined at the measurement wavelength. The furfural content in the fermentation broth was calculated with reference to the standard curve. The results show that the maximum absorption wavelength of furfural is 276nm, which is the measurement wavelength. The linear regression equation of furfural standard curve is： y = 0.164x ＋ 0.001, R squared = 0.999, and the linearity within the measurement rangeis good. The content of furfural in fermentation broth is 0.0244 g/ml. The precision RSD value is 0.315 % , and the precision of the instrument is good. The stability RSD value was 0.450 % , and the samples under test were stable within 120 min. Reproducibility RSD was 0.828 % , and the test method had good reproducibility. The recovery rate is 99.12 % -100.35 % , and its RSD value is 0.617 % . This method is easy to grasp, fast in measurement, good in stability and low in cost of equipment, which is conducive to basic research and promotion. It provides a reference for some methods and data for the further study on the content of other secondary metabolites of Aspergillusniger.