厌氧条件下,微生物的代谢速率很缓慢。而低强度超声辐照则可以有效促进微生物的活性,进而增强生化反应速率。基于此,文章采用低强度超声预处理耐盐醌还原菌群,研究在富盐环境下其对醌介导偶氮染料的厌氧生物脱色速率的影响。研究结果表明,低强度超声(辐射频率40 kHz)处理耐盐醌还原菌群的最佳条件为超声强度0.15 W/cm2,超声时间3 min。在50 g/L NaCl存在条件下,处理后的耐盐醌还原菌群能够使蒽醌-2-磺酸钠、蒽醌-2,6-二磺酸钠、2-羟基-1,4-萘醌和2-甲基-1,4-萘醌介导的偶氮染料酸性大红3R脱色速率分别提高8.8%,23.0%,4.2%及20.4%。通过透射电镜分析推测,低强度超声可能是通过增大生物细胞壁的比表面积来提高其传质能力,从而提高醌介导的偶氮染料脱色速率。
A bench scale experiment was conducted to investigate low intensity ultrasound(LIU),which was effectively increase microorganisms activities,in treating the salt-tolerant quinine-reducing(STQR) consortium under saline condition(NaCl conc.50 g/L).Effect of quinine-mediated bio-degradation of azo dye at irradiation frequency of 40 kHz was studied.The experiment result showed the optimum condition of pretreatment as 0.15 W/cm2 of ultrasound intensity,and 3 min of irradiation time.Through analysis of the cells of bacterial consortium using transmission electron microscope,it could be presupposed that LIU increases the mass transfer ability of cells by increasing their specific surface areas so that bio decolorization rate of azo-dye is enhanced.