[vc_empty_space][vc_empty_space]
Exploring levan-producing bacteria chromohalobacter japonicus bk-Ab 18 for biobeneficiation of bauxite through the investigation of its levansucrase properties
Hertadi R.a, Nasir D.Q.a, Mufti N.b
a Department of Chemistry, Biochemistry Research Division, Bandung Institute of Technology, Bandung, West Java, Indonesia
b Department of Physics, State University of Malang, Malang, East Java, Indonesia
[vc_row][vc_column][vc_row_inner][vc_column_inner][vc_separator css=”.vc_custom_1624529070653{padding-top: 30px !important;padding-bottom: 30px !important;}”][/vc_column_inner][/vc_row_inner][vc_row_inner layout=”boxed”][vc_column_inner width=”3/4″ css=”.vc_custom_1624695412187{border-right-width: 1px !important;border-right-color: #dddddd !important;border-right-style: solid !important;border-radius: 1px !important;}”][vc_empty_space][megatron_heading title=”Abstract” size=”size-sm” text_align=”text-left”][vc_column_text]© 2018 Global Science Publications. All rights reserved.Present study shows that the potential application of levan-producing bacteria Chromohalobacter japonicus BK-AB 18 to reduce iron content in a bauxite sample (bio-beneficiation) evaluated by characterizing its extracellular levansucrase, an enzyme that catalyzes levan production. Extracellular levansucrase produced by growing the bacteria in a modified Belghith medium [1 % tryptone, 0.5 % yeast extract, 0.25 % K2HPO4, 7.5 % (w/v) NaCl and 7.5 % (w/v) sucrose] in a rotary shaker overnight, at 37 °C and 150 rpm. The partial purified enzyme has molecular weight of about 50 kDa and exhibited optimum activity at pH 6, 55 °C and 5 % NaCl. Levansucrase activity enhanced up to 18 % by the presence of Ca2+ and Co2+ ions but strongly inhibited by Si2+, Fe3+ and Zn2+ ions. A biobeneficiation potential of the bacteria was evaluated by growing it in the Belghith medium containing 1%(w/v) of a bauxite sample. The amount of iron bound by levan produced by the bacteria quantified periodically with atomic adsorption spectroscopy. Values were found to plateau after 24 hours of biobeneficiation. The iron content in the bauxite sample decreased by 20 % after 48 hours of biobeneficiation. This result suggests that levansucrase produced by C. japonicus BK-AG 18 was relatively active throughout the bio-beneficiation process and has not significantly inhibited by impurities in the bauxite sample.[/vc_column_text][vc_empty_space][vc_separator css=”.vc_custom_1624528584150{padding-top: 25px !important;padding-bottom: 25px !important;}”][vc_empty_space][megatron_heading title=”Author keywords” size=”size-sm” text_align=”text-left”][vc_column_text][/vc_column_text][vc_empty_space][vc_separator css=”.vc_custom_1624528584150{padding-top: 25px !important;padding-bottom: 25px !important;}”][vc_empty_space][megatron_heading title=”Indexed keywords” size=”size-sm” text_align=”text-left”][vc_column_text]Bauxite,Bio-beneficiation,Choromohalobacter japonicus BK-AB18,Levan,Levansucrase[/vc_column_text][vc_empty_space][vc_separator css=”.vc_custom_1624528584150{padding-top: 25px !important;padding-bottom: 25px !important;}”][vc_empty_space][megatron_heading title=”Funding details” size=”size-sm” text_align=”text-left”][vc_column_text]This work funded by Priority Research Grant from Indonesian Ministry of Research & Technology with the contract number of 585u/I1.C01/PL/2016.[/vc_column_text][vc_empty_space][vc_separator css=”.vc_custom_1624528584150{padding-top: 25px !important;padding-bottom: 25px !important;}”][vc_empty_space][megatron_heading title=”DOI” size=”size-sm” text_align=”text-left”][vc_column_text][/vc_column_text][/vc_column_inner][vc_column_inner width=”1/4″][vc_column_text]Widget Plumx[/vc_column_text][/vc_column_inner][/vc_row_inner][/vc_column][/vc_row][vc_row][vc_column][vc_separator css=”.vc_custom_1624528584150{padding-top: 25px !important;padding-bottom: 25px !important;}”][/vc_column][/vc_row]