In the present study, a phenol degrading actinomycetes strain was isolated from paper pulp wastewater. The isolated strain was identified as Rhodococcus pyridinivorans PDB9TN-1 using 16S rRNA gene sequencing technique, which yielded the complete degradation of 1600 mg l⁻¹ of phenol within 56 h. Moreover, the Rhodococcus species could remove over 97.5% of total organic carbon (TOC) at an initial phenol concentration of 1000 mg l⁻¹. The metabolic profile of phenol biodegradation by the actinomycetes species has been investigated using liquid chromatography–mass spectrometry (LC-MS) and Fourier-transform infrared spectroscopy (FT-IR). The key intermediate products detected in the actinomycetes culture were hydroquinone, protocatechuic acid, beta-carboxycis-cismuconate, maleyl acetate, 4–oxalocrotonic acid and 3-fumarylpyruvic acid. Further, a tentative oxalocrotonic acid pathway has been proposed on the basis of the detected intermediate products. The culture medium constituents are highly indispensable for the microbial growth, enzyme and other cellular metabolic activities associated with phenol biodegradation. Therefore, the effect of media components were modelled with the help of response surface methodology (RSM) and central composite design (CCD). A reliable quadratic model was established which predicted the degradation efficiency as high as 99.5% with an appreciable correlation coefficient (R²) of 0.98. Moreover, phenol degradation efficiency was improved with concentrations beyond the central values for all media components except K₂HPO₄ and NaCl.

在本研究中，从纸浆废水中分离出了降解苯酚的放线菌菌株。使用16S rRNA基因测序技术，将分离出的菌株鉴定为吡啶菌（Rhodococcus pyridinivorans）PDB9T N-1，该^菌株在56 h内可降解1600 mg l ^-1的苯酚。此外，在初始苯酚浓度为1000 mg l ^{-1的情况下}，红球菌可去除总有机碳（TOC）的97.5％。已使用液相色谱-质谱（LC-MS）和傅里叶变换红外光谱（FT-IR）研究了放线菌物种对苯酚生物降解的代谢特征。放线菌中检测到的关键中间产物培养物中包括对苯二酚，原儿茶酸，β-羧基顺式粘康酸酯，顺丁烯二酸乙酸酯，4-草酰巴豆酸和3-呋喃芳基丙酮酸。此外，已经基于检测到的中间产物提出了一种暂时的草酰巴豆酸途径。对于与酚生物降解有关的微生物生长，酶和其他细胞代谢活性，培养基成分是必不可少的。因此，借助响应面方法（RSM）和中央复合设计（CCD）对媒体组件的效果进行建模。建立了可靠的二次模型，该模型预测降解效率高达99.5％，并且相关系数（R ²）的0.98。此外，除K ₂ HPO ₄和NaCl外，所有介质组分的浓度均超过中心值，从而提高了苯酚的降解效率。