This work presents a novel, robust procedure for the semi-automated counting of colony-forming units of Bacillus pumilus (a bacterium) and Meyerozyma guilliermondii (a yeast) both isolated from diesel oil. The counting is performed from digital images of Petri dishes containing the samples by a developed Python code, and the images are acquired from a low-cost scanning apparatus. The counting algorithm is based on the similar morphological characteristics of the bacterium and the yeast colonies. It was compared with classical counting methodology, and the results showed calibration and validation curves with a coefficient of determination (R²) of 0.99 and 0.98, respectively. The developed methodology is a valuable alternative to estimate the microbial contamination of biofuels.

这项工作提出了一种新颖、稳健的程序，用于对从柴油中分离出来的短小芽孢杆菌（一种细菌）和吉里蒙氏菌（一种酵母）的菌落形成单位进行半自动计数。计数是通过开发的 Python 代码对包含样本的培养皿的数字图像进行的，并且图像是从低成本扫描设备获取的。计数算法基于细菌和酵母菌落的相似形态特征。与经典计数方法进行比较，结果显示校准曲线和验证曲线的决定系数 (R ² ) 分别为 0.99 和 0.98。所开发的方法是估计生物燃料微生物污染的一个有价值的替代方案。