search
for
 About Bioline  All Journals  Testimonials  Membership  News  Donations


International Journal of Environment Science and Technology
Center for Environment and Energy Research and Studies (CEERS)
ISSN: 1735-1472
EISSN: 1735-2630
Vol. 11, No. 7, 2014, pp. 1911-1918
Bioline Code: st14187
Full paper language: English
Document type: Research Article
Document available free of charge

International Journal of Environment Science and Technology, Vol. 11, No. 7, 2014, pp. 1911-1918

 en Enhancement of nickel biosorption on fungal biomass by enzymatic and alkali pretreatments
Rouhollahi, F.; Zamani, A.; Karimi, K. & Etesami, N.

Abstract

Enzymatic and alkali pretreatments were employed to improve nickel biosorption capacity of Rhizomucor pusillus check for this species in other resources biomass. Pretreatment with 0.002–80 g l-1 NaOH and 0.0001–0.1 Anson Unit (AU) g-1 protease enhanced the biosorption capacity of fungal biomass. Increasing the concentration of NaOH from 0.002 to 5 g l-1 improved nickel removal from 93.2 to 100.0 % while untreated biomass showed 64.6 % Ni(II) removal. Pretreatment with higher concentrations of NaOH, 5–80 g l-1 resulted in nearly complete removal of nickel ions. Pretreatment of the biomass with 0.0001 AU g-1 protease improved the nickel removal to over 91 %, while increasing the enzyme loading to 0.1 AU g-1 improved the removal to 93 %. Untreated biomass removed 78.4, 63.0, and 96.3 %of chromium, copper, and lead ions, respectively, from a mixture solution of the ions. Respective metal removals were increased to 100, 98.9, and 100 % after pretreatment with 0.2 g l-1 NaOH solution and to 87.8, 86.7, and 100 % after the enzymatic pretreatment with 0.1 AU g-1 protease. Scanning electron microscopy analysis indicated that alkali and enzymatic pretreatments enhanced the porosity of the biomass. Furthermore, compositional analysis showed that both of the pretreatments removed a major part of fungal proteins (2.1–95.8 % removal). Glucosamine, N-acetyl glucosamine, and phosphates were the major ingredients of the pretreated biomass.

Keywords
Alkali pretreatment; Biosorption; Enzymatic pretreatment; Heavy metal removal; Rhizomucor pusillus

 
© Copyright 2015 - International Journal of Environment Science and Technology
Alternative site location: http://www.ijest.org

Home Faq Resources Email Bioline
© Bioline International, 1989 - 2017, Site last up-dated on 05-Dec-2017.
Site created and maintained by the Reference Center on Environmental Information, CRIA, Brazil
System hosted by the Internet Data Center of Rede Nacional de Ensino e Pesquisa, RNP, Brazil