Role of melanin in fungal biosorption of tributyltin chloride

TY - JOUR

T1 - Role of melanin in fungal biosorption of tributyltin chloride

AU - Gadd, G. M.

AU - Gray, D. J.

AU - Newby, P. J.

PY - 1990/10

Y1 - 1990/10

N2 - Intact biomass of an albino and a melanic strain of Aureobacidium pullulans, as well as purified melanin from the latter strain, was capable of tributyltin chloride (TBTC) removal from solution. Melanized biomass had a greater biosorptive capacity than albino biomass, this difference being attributable to the presence of melanin. Purified melanin had a large capacity for TBTC biosorption, the calculated maximum uptake capacity, qe, being approximately 35 mmol (g dry wt)-1. TBTC biosorption by intact biomass and melanin obeyed the Langmuir adsorption isotherm over the concentration range used, and was relatively unaffected by external pH between pH 3.5 and 6.5: an approximate 20% decrease in TBTC biosorption resulted at external pH 2.5. A TBTC concentration of 0.3 μM in growth medium resulted in a lag period which was longer with the albino strain (approximately 50 h) than with the pigmented strain (approximately 25 h). The addition of melanin to TBTC-containing growth media resulted in a reduction in toxicity and attainment of higher cell yields. The applied and environmental significance of these interactions are discussed.

AB - Intact biomass of an albino and a melanic strain of Aureobacidium pullulans, as well as purified melanin from the latter strain, was capable of tributyltin chloride (TBTC) removal from solution. Melanized biomass had a greater biosorptive capacity than albino biomass, this difference being attributable to the presence of melanin. Purified melanin had a large capacity for TBTC biosorption, the calculated maximum uptake capacity, qe, being approximately 35 mmol (g dry wt)-1. TBTC biosorption by intact biomass and melanin obeyed the Langmuir adsorption isotherm over the concentration range used, and was relatively unaffected by external pH between pH 3.5 and 6.5: an approximate 20% decrease in TBTC biosorption resulted at external pH 2.5. A TBTC concentration of 0.3 μM in growth medium resulted in a lag period which was longer with the albino strain (approximately 50 h) than with the pigmented strain (approximately 25 h). The addition of melanin to TBTC-containing growth media resulted in a reduction in toxicity and attainment of higher cell yields. The applied and environmental significance of these interactions are discussed.

KW - Biomass

KW - Biosorption

KW - Uptake Capacity

KW - Maximum Uptake

KW - Langmuir Adsorption Isotherm

UR - https://www.scopus.com/pages/publications/0025043409

U2 - 10.1007/BF00170934

DO - 10.1007/BF00170934

M3 - Article

AN - SCOPUS:0025043409

SN - 0175-7598

VL - 34

SP - 116

EP - 121

JO - Applied Microbiology and Biotechnology

JF - Applied Microbiology and Biotechnology

IS - 1

ER -