With low bioaccessbility, persistence of the undissolved organic pollutants in soil and sediments poses threat to health of the resident. Although ubiquitous black carbon catalyzes a wide range of biogeochemical reactions in nature, its role in biotransformation of the compounds in non-aqueous phase like 2, 2′-nitrobiphenyl remains unclear. Reduction rate constants of 2, 2′-dinitrobiphenyl by Shewanella oneidensis MR-1 increased from 0.0044 h⁻¹ by 7-fold to 0.035 h⁻¹ in the presence of black carbons produced at pyrolysis temperature of 250–900 °C. Accordingly, electrical conductivity of black carbon was enhanced from 0 to 5.56 S∙cm⁻¹. The reactivity of black carbon for catalyzing the biotransformation positively correlated with its electrical conductivity (R² > 0.89), which was strongly associated with conductive graphitic clusters in it. The surface oxygenated groups in black carbon were likely not involved in the bioreduction. This work attaches importance to role of the ubiquitous black carbon in natural biotransformation of the undissolved pollutants, and elucidates new mechanism for the biotransformation.

由于生物可及性低，土壤和沉积物中未溶解的有机污染物的持久性对居民的健康构成威胁。尽管无处不在的黑碳在自然界中催化了广泛的生物地球化学反应，但其在非水相化合物（如 2, 2'-硝基联苯）的生物转化中的作用仍不清楚。在 250–900 °C 热解温度下产生的黑碳存在的情况下，Shewanella oneidensis MR-1 对2, 2'-二硝基联苯的还原速率常数从 0.0044 h ^-1增加了7 倍至 0.035 h ^{-1 。}因此，黑碳的电导率从 0 提高到 5.56 S∙cm ^-1. 黑炭催化生物转化的反应活性与其电导率正相关（R ²  > 0.89），这与其中的导电石墨簇密切相关。黑碳中的表面氧化基团可能不参与生物还原。这项工作重视无处不在的黑碳在未溶解污染物的自然生物转化中的作用，并阐明了生物转化的新机制。