Wang Jianlong, Chen Can
Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, PR China.
Biotechnol Adv. 2006 Sep-Oct;24(5):427-51. doi: 10.1016/j.biotechadv.2006.03.001. Epub 2006 Jun 5.
Heavy metal pollution has become one of the most serious environmental problems today. Biosorption, using biomaterials such as bacteria, fungi, yeast and algae, is regarded as a cost-effective biotechnology for the treatment of high volume and low concentration complex wastewaters containing heavy metal(s) in the order of 1 to 100 mg/L. Among the promising biosorbents for heavy metal removal which have been researched during the past decades, Saccharomyces cerevisiae has received increasing attention due to the unique nature in spite of its mediocre capacity for metal uptake compared with other fungi. S. cerevisiae is widely used in food and beverage production, is easily cultivated using cheap media, is also a by-product in large quantity as a waste of the fermentation industry, and is easily manipulated at molecular level. The state of the art in the field of biosorption of heavy metals by S. cerevisiae not only in China, but also worldwide, is reviewed in this paper, based on a substantial number of relevant references published recently on the background of biosorption achievements and development. Characteristics of S. cerevisiae in heavy metal biosorption are extensively discussed. The yeast can be studied in various forms for different purposes. Metal-binding capacity for various heavy metals by S. cerevisiae under different conditions is compared. Lead and uranium, for instances, could be removed from dilute solutions more effectively in comparison with other metals. The yeast biosorption largely depends on parameters such as pH, the ratio of the initial metal ion and initial biomass concentration, culture conditions, presence of various ligands and competitive metal ions in solution and to a limited extent on temperature. An assessment of the isotherm equilibrium model, as well as kinetics was performed. The mechanisms of biosorption are understood only to a limited extent. Elucidation of the mechanism of metal uptake is a real challenge in the field of biosorption. Various mechanism assumptions of metal uptake by S. cerevisiae are summarized.
重金属污染已成为当今最严重的环境问题之一。生物吸附法利用细菌、真菌、酵母和藻类等生物材料，被视为一种具有成本效益的生物技术，用于处理大量低浓度且重金属含量在1至100毫克/升范围内的复杂废水。在过去几十年中研究的用于去除重金属的有前景的生物吸附剂中，酿酒酵母尽管与其他真菌相比其金属吸收能力一般，但因其独特的性质而受到越来越多的关注。酿酒酵母广泛应用于食品和饮料生产，易于使用廉价培养基培养，也是发酵工业大量产生的废弃物副产品，并且在分子水平上易于操作。本文基于最近在生物吸附成果和发展背景下发表的大量相关参考文献，综述了酿酒酵母对重金属生物吸附领域的现状，不仅在中国，而且在世界范围内。广泛讨论了酿酒酵母在重金属生物吸附中的特性。可以针对不同目的以各种形式研究这种酵母。比较了酿酒酵母在不同条件下对各种重金属的金属结合能力。例如，与其他金属相比，铅和铀可以更有效地从稀溶液中去除。酵母生物吸附很大程度上取决于pH值、初始金属离子与初始生物量浓度的比例、培养条件、溶液中各种配体和竞争性金属离子的存在，并且在一定程度上还取决于温度。对等温线平衡模型以及动力学进行了评估。生物吸附的机制仅在有限程度上得到了解。阐明金属吸收机制是生物吸附领域的一项真正挑战。总结了酿酒酵母吸收金属的各种机制假设。
