title: Purification, characterization, and potential of saline waste water remediation of a polyextremophilic α-amylase from an obligate halophilic Aspergillus gracilis.
abstract: An obligate halophilic Aspergillus gracilis which was isolated from a hypersaline man-made saltern from Thailand was screened for its potential of producing extracellular α -amylase in the previous studies. In this study the α -amylase was extracted and purified by the help of column chromatography using Sephadex G-100 column. Presence of amylase was verified by SDS-PAGE analysis, showing a single band of approximately 35 kDa. The specific activity of the enzyme was found to be 131.02 U/mg. The Lineweaver-Burk plot showed the V max and K m values of 8.36 U/mg and 6.33 mg/mL, respectively. The enzyme was found to have the best activity at 5 pH, 60°C, and 30% of NaCl concentration, showing its polyextremophilic nature. The use of various additives did not show much variation in the activity of enzyme, showing its resilience against inhibitors. The enzyme, when tested for its use for synthetic waste water remediation by comparing its activity with commercial amylase in different salt concentrations showed that the α -amylase from A. gracilis was having better performance at increasing salt concentrations than the commercial one. This shows its potential to be applied in saline waste water and other low water activity effluents for bioremediation.
authors.affiliation: Plant Biomass Utilization Research Unit, Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand ; Institute of Biochemistry, University of Balochistan, Quetta 87300, Pakistan.
authors.forename: Imran
authors.initials: I
authors.lastname: Ali
authors.affiliation: Food Engineering and Bioprocess Technology, School of Environment, Resources and Development, Asian Institute of Technology, Klong Luang, Pathumthani 12120, Thailand.
authors.forename: Ali
authors.initials: A
authors.lastname: Akbar
authors.affiliation: Plant Biomass Utilization Research Unit, Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Benjawan
authors.initials: B
authors.lastname: Yanwisetpakdee
authors.affiliation: Plant Biomass Utilization Research Unit, Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Sehanat
authors.initials: S
authors.lastname: Prasongsuk
authors.affiliation: Plant Biomass Utilization Research Unit, Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Pongtharin
authors.initials: P
authors.lastname: Lotrakul
authors.affiliation: Plant Biomass Utilization Research Unit, Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Hunsa
authors.initials: H
authors.lastname: Punnapayak
mesh_terms: D001230:Aspergillus / Q000201:enzymology*; D005656:Fungal Proteins / Q000737:chemistry*; D054712:Salinity; D062065:Wastewater / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*; D000516:alpha-Amylases / Q000737:chemistry*
chemical_list: D005656:Fungal Proteins; D062065:Wastewater; D000516:alpha-Amylases