Microbial removal of heavy metals from agricultural and marine industrial wastes in a sequential and mixed cultivation

研究了微生物去除农业和海洋工业废物中的重金属，特别是镉。在蛋白水解菌和硫酸盐产生菌的顺序和混合培养过程中，每个废物的提取物中的重金属，如镉，作为金属硫化物的沉淀物几乎完全被去除。而单独培养蛋白水解菌或硫酸盐还原菌后，萃取物中残留了大量的重金属。这些结果表明，农业和海洋工业废弃物中的重金属可能与金属硫蛋白等重金属结合蛋白结合在一起，并通过蛋白水解菌分泌的蛋白酶转化为游离态。硫酸盐还原菌产生的重金属和硫化氢游离态形成金属硫化物沉淀物。免餐制剂的供应情况。饲料也进行了检查。

Microbial removal of heavy metals, especially cadmium, from agricultural and marine industrial wastes were examined. During sequential and mixed cultivation of proteolytic microbes and a strain of sulfate-educing bacteria in an extracts of each waste, heavy metals like cadmium were removed almost completely from the extract as the metal-sulfide precipitate. Whereas a ant amounts of heavy metals remained in the extract after the cultivation of proteolytic microbes or the sulfate-reducing bacterium alone.These results suggested that heavy metals in agricultural and marine industrial wastes would be present as bound-state with heavy-metal-binding protein such as metallothionein and they would be transformed to the free-state by protease secreted by proteolytic microbes. And then metal-sulfide precipitates could be formed with the free-state of heavy metals and hydrogen sulfide produced by the sulfate-reducing bacterium. Availability of meal-free preparations as. feed were also examined.