Zakaria Nur Nadhirah, Gomez-Fuentes Claudio, Abdul Khalil Khalilah, Convey Peter, Roslee Ahmad Fareez Ahmad, Zulkharnain Azham, Sabri Suriana, Shaharuddin Noor Azmi, Cárdenas Leyla, Ahmad Siti Aqlima
Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia.
Department of Chemical Engineering, Universidad de Magallanes, Avda. Bulnes, Punta Arenas 01855, Región de Magallanes y Antártica Chilena, Chile.
Microorganisms. 2021 Jun 3;9(6):1213. doi: 10.3390/microorganisms9061213.
Hydrocarbon pollution is widespread around the globe and, even in the remoteness of Antarctica, the impacts of hydrocarbons from anthropogenic sources are still apparent. Antarctica's chronically cold temperatures and other extreme environmental conditions reduce the rates of biological processes, including the biodegradation of pollutants. However, the native Antarctic microbial diversity provides a reservoir of cold-adapted microorganisms, some of which have the potential for biodegradation. This study evaluated the diesel hydrocarbon-degrading ability of a psychrotolerant marine bacterial consortium obtained from the coast of the north-west Antarctic Peninsula. The consortium's growth conditions were optimised using one-factor-at-a-time (OFAT) and statistical response surface methodology (RSM), which identified optimal growth conditions of pH 8.0, 10 °C, 25 ppt NaCl and 1.5 g/L NHNO. The predicted model was highly significant and confirmed that the parameters' salinity, temperature, nitrogen concentration and initial diesel concentration significantly influenced diesel biodegradation. Using the optimised values generated by RSM, a mass reduction of 12.23 mg/mL from the initial 30.518 mg/mL (4% ()) concentration of diesel was achieved within a 6 d incubation period. This study provides further evidence for the presence of native hydrocarbon-degrading bacteria in non-contaminated Antarctic seawater.
碳氢化合物污染在全球范围内广泛存在，即使在遥远的南极洲，人为来源的碳氢化合物影响依然明显。南极洲长期低温及其他极端环境条件降低了包括污染物生物降解在内的生物过程速率。然而，南极洲本土的微生物多样性提供了一个适应寒冷的微生物库，其中一些具有生物降解潜力。本研究评估了从南极半岛西北部海岸获得的耐冷海洋细菌群落对柴油碳氢化合物的降解能力。采用单因素法（OFAT）和统计响应面法（RSM）优化了该群落的生长条件，确定了pH 8.0、10℃、25 ppt NaCl和1.5 g/L NHNO的最佳生长条件。预测模型高度显著，证实盐度、温度、氮浓度和初始柴油浓度等参数对柴油生物降解有显著影响。使用RSM生成的优化值，在6天的培养期内，初始浓度为30.518 mg/mL（4%（））的柴油质量减少了12.23 mg/mL。本研究为未受污染的南极海水中存在本土碳氢化合物降解细菌提供了进一步证据。
