Jalali Jihen, Magdich Salwa, Jarboui Raja, Loungou Mouna, Ammar Emna
Research Unit "Coastal and Urban Environments" National Engineering School of Sfax, BP 1173, 3038 Sfax, Tunisia; Tunisian Chemical Group, M'Dhilla-Gafsa factory, B.P. 215, 2100 Gafsa, Tunisia.
Research Unit "Coastal and Urban Environments" National Engineering School of Sfax, BP 1173, 3038 Sfax, Tunisia.
J Hazard Mater. 2016 May 5;308:362-73. doi: 10.1016/j.jhazmat.2016.01.063. Epub 2016 Jan 29.
Aerobic microorganisms able to grow on phosphogypsum (PG), characterized by heavy metals accumulation and high acidity were investigated by enrichment cultures. The PG was used at different concentrations, varying from 20 to 200 g/L in the enrichment culture medium supplemented with compost and Tamarix roots. This treatment reduced COD and heavy metals PG concentration. An efficient isolated fungus, identified by molecular approach as Trichoderma asperellum, was able to grow on PG as the sole carbon and energy sources at the different experimented concentrations, and to increase the culture media pH of the different PG concentrations used to 8.13. This fact would be the result of alkaline compound released during the fungus PG solubilization. Besides, the heavy metals and COD removal exceeded 52% after 7 days culture. At 200 g/LPG concentration, the experimented strain was able to reduce COD by 52.32% and metals concentrations by 73% for zinc, 63.75% for iron and 50% for cadmium. This exhibited the T. asperellum efficiency for heavy metals accumulation and for phosphogypsum bioremediation.
通过富集培养研究了能够在磷石膏（PG）上生长、以重金属积累和高酸度为特征的需氧微生物。在添加了堆肥和柽柳根的富集培养基中，使用了浓度范围为20至200 g/L的不同浓度的PG。这种处理降低了化学需氧量（COD）和PG中的重金属浓度。通过分子方法鉴定出一种高效分离真菌为棘孢木霉，它能够在不同实验浓度下以PG作为唯一碳源和能源生长，并将所用不同PG浓度的培养基pH值提高到8.13。这一事实是真菌溶解PG过程中释放碱性化合物的结果。此外，培养7天后，重金属和COD去除率超过52%。在200 g/L PG浓度下，受试菌株能够将COD降低52.32%，将锌的金属浓度降低73%，铁降低63.75%，镉降低50%。这显示了棘孢木霉在重金属积累和磷石膏生物修复方面的效率。
