The surface of pyrite exposed to the thermophilic archaeon Acidianus brierleyi was investigated to elucidate the impact of extracellular polymeric substances (EPS) and/or cells on mineral surface hydrophobicity. The interaction of cells with the surface of pyrite and the physicochemical properties of the mineral surface were studied using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), captive bubble contact angle measurements and time of flight – secondary ion mass spectrometry (ToF-SIMS). The ToF-SIMS results show no clear evidence of EPS on the pyrite surface after exposure to A. brierleyi and further suggests significant contamination of the surface by the yeast extract included in the recommended A. brierleyi growth medium. It was found that the presence of yeast extract made it impossible to accurately determine the action of EPS on the surface, and potentially impeded chemical and biological reactions and interactions on the surface. Investigation of the impact of A. brierleyi on pyrite in the absence of yeast extract found up to 24° decrease in contact angle compared to the control after 2 h. It was found that A. brierleyi produced very little EPS and as such is unlikely to alter the surface through a contact mechanism, with little to no cell attachment observed on the pyrite surface. Thus removal of yeast extract may improve the application of this archaea to biomining applications.

研究了暴露于嗜热古细菌Acidianus brierleyi的黄铁矿表面，以阐明细胞外聚合物（EPS）和/或细胞对矿物表面疏水性的影响。使用扫描电子显微镜（SEM），能量色散X射线光谱（EDX），俘获气泡接触角测量和飞行时间–次级离子质量研究了细胞与黄铁矿表面的相互作用以及矿物表面的理化性质。光谱法（ToF-SIMS）。ToF-SIMS结果表明，暴露于Brierleyi菌后，黄铁矿表面没有EPS的明确证据，并且进一步表明推荐的Brierleyi菌中所含的酵母提取物对表面有明显的污染。生长培养基。已经发现，酵母提取物的存在使得不可能精确地确定EPS在表面上的作用，并且潜在地阻碍了表面上的化学和生物反应以及相互作用。在不添加酵母提取物的情况下，调查了菜青曲霉对黄铁矿的影响，发现与2小时后的对照相比，接触角降低了24°。发现布里氏曲霉产生很少的EPS，因此不太可能通过接触机理改变表面，在黄铁矿表面几乎没有观察到细胞附着。因此，去除酵母提取物可以改善该古细菌在生物采矿应用中的应用。