Departamento de Microbiologia, Instituto de Ciências Biomédicas II, Universidade de São Paulo, São Paulo, São Paulo, Brazil.
Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo, São Paulo, São Paulo, Brazil.
PLoS One. 2014 Jan 29;9(1):e87968. doi: 10.1371/journal.pone.0087968. eCollection 2014.
In this study was developed a natural process using a biological system for the biosynthesis of nanoparticles (NPs) and possible removal of copper from wastewater by dead biomass of the yeast Rhodotorula mucilaginosa. Dead and live biomass of Rhodotorula mucilaginosa was used to analyze the equilibrium and kinetics of copper biosorption by the yeast in function of the initial metal concentration, contact time, pH, temperature, agitation and inoculum volume. Dead biomass exhibited the highest biosorption capacity of copper, 26.2 mg g(-1), which was achieved within 60 min of contact, at pH 5.0, temperature of 30°C, and agitation speed of 150 rpm. The equilibrium data were best described by the Langmuir isotherm and Kinetic analysis indicated a pseudo-second-order model. The average size, morphology and location of NPs biosynthesized by the yeast were determined by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM). The shape of the intracellularly synthesized NPs was mainly spherical, with an average size of 10.5 nm. The X-ray photoelectron spectroscopy (XPS) analysis of the copper NPs confirmed the formation of metallic copper. The dead biomass of Rhodotorula mucilaginosa may be considered an efficiently bioprocess, being fast and low-cost to production of copper nanoparticles and also a probably nano-adsorbent of this metal ion in wastewater in bioremediation process.
在这项研究中,开发了一种使用生物系统的自然过程,用于合成纳米粒子 (NPs),并通过死酵母 Rhodotorula mucilaginosa 的生物质来去除废水中的铜。使用死酵母和活酵母 Rhodotorula mucilaginosa 来分析铜在初始金属浓度、接触时间、pH 值、温度、搅拌和接种量的影响下通过酵母的平衡和动力学吸附。死生物质表现出最高的铜吸附能力,为 26.2 mg g(-1),在 60 分钟的接触时间内,在 pH 值为 5.0、温度为 30°C 和搅拌速度为 150 rpm 的条件下达到。平衡数据最好由 Langmuir 等温线描述,动力学分析表明符合伪二阶模型。酵母生物合成的 NPs 的平均大小、形态和位置通过扫描电子显微镜 (SEM)、能量色散 X 射线光谱 (EDS) 和透射电子显微镜 (TEM) 确定。细胞内合成的 NPs 的形状主要为球形,平均尺寸为 10.5nm。铜 NPs 的 X 射线光电子能谱 (XPS) 分析证实了金属铜的形成。死酵母 Rhodotorula mucilaginosa 的生物质可以被认为是一种高效的生物过程,用于生产铜纳米粒子快速且低成本,并且在生物修复过程中可能是这种金属离子的纳米吸附剂。