【摘要】 25-37℃时,深红酵母对Cd2+的吸附随温度升高而增加.25℃时,每克深红酵母菌(湿重)吸附Cd2+6.81mg(即6.81mg·g-1),37℃时上升到8.78mg·g-1.假丝酵母吸附Cd2+受温度的影响与深红酵母相似.环境pH<4时,两酵母菌对Cd2+的吸附均较少并随pH升高而缓慢增加;当4<pH≤5时,随着pH的升高,对Cd2+吸附量急剧增加,并在pH=5时达到高峰,此时深红酵母吸附量为8.43mg·g-1,假丝酵母为14.05mg·g-1;pH>5时,对Cd2+的吸附量开始减小.吸附动力试验结果显示,吸附主要发生在开始的半小时内.在37℃,pH=5,菌龄48h,吸附1h的条件下,深红酵母吸附量为8.86mg·g-1,假丝酵母则达15.02mg·g-1.更多还原

【Abstract】 The effects of some environmental and operational conditions on Cd²⁺ bioadsorption by two kinds of yeast were studied. The results showed that the adsorption ability of Cd²⁺ by Rhodotorula rubra was improved as the environmental temperature increased from 25 to 37 ℃. The adsorbed Cd²⁺ by R.rubra reached 6.81 mg·g^-1 at 25 ℃ and 8.78 mg·g^-1 when the operation temperature was at 37 ℃. The effects of temperature on Cd²⁺ bioadsorption by Candida tropicalis was similer to R.rubra. The ability of Cd²⁺ absorption was poor when the environmental pH was below 4.0, but sharply improved when the pH was above 4.0 and reached the maximal adsorption rate of R.rubra 8.43 mg·g^-1 and C.tropicalis 14.05 mg·g^-1 at pH 5.0. Cd²⁺ adsorption rate of the two kinds of yeast decreased at the environmental pH>5.0. The results of adsorption dynamics experiment showed that the yeasts adsorbed Cd²⁺ mainly at the beginning of half hour. The adsorption rates of R.rubra and C.tropicalis were 8.86 mg·g^-1 and 15.02 mg·g^-1 respectively under the conditions of 37 ℃, pH 5.0 and 48 h bacteria age.更多还原