title: Identification of Key Factors Involved in the Biosorption of Patulin by Inactivated Lactic Acid Bacteria (LAB) Cells.
abstract: The purpose of this study was to identify the key factors involved in patulin adsorption by heat-inactivated lactic acid bacteria (LAB) cells. For preventing bacterial contamination, a sterilization process was involved in the adsorption process. The effects of various physical, chemical, and enzymatic pre-treatments, simultaneous treatments, and post-treatments on the patulin adsorption performances of six LAB strains were evaluated. The pre-treated cells were characterized by scanning electron microscopy (SEM). Results showed that the removal of patulin by viable cells was mainly based on adsorption or degradation, depending on the specific strain. The adsorption abilities were widely increased by NaOH and esterification pre-treatments, and reduced by trypsin, lipase, iodate, and periodate pre-treatments. Additionally, the adsorption abilities were almost maintained at pH 2.2-4.0, and enhanced significantly at pH 4.0-6.0. The effects of sodium and magnesium ions on the adsorption abilities at pH 4 were slight and strain-specific. A lower proportion of patulin was released from the strain with higher adsorption ability. Analyses revealed that the physical structure of peptidoglycan was not a principal factor. Vicinal OH and carboxyl groups were not involved in patulin adsorption, while alkaline amino acids, thiol and ester compounds were important for patulin adsorption. Additionally, besides hydrophobic interaction, electrostatic interaction also participated in patulin adsorption, which was enhanced with the increase in pH (4.0-6.0).
authors.affiliation: College of Food Science and Engineering, Northwest A & F University, Yangling, Shaanxi, 712100, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Wang
authors.affiliation: College of Food Science and Engineering, Northwest A & F University, Yangling, Shaanxi, 712100, China.
authors.forename: Zhouli
authors.initials: Z
authors.lastname: Wang
authors.affiliation: College of Food Science and Engineering, Northwest A & F University, Yangling, Shaanxi, 712100, China.
authors.forename: Yahong
authors.initials: Y
authors.lastname: Yuan
authors.affiliation: College of Food Science and Engineering, Northwest A & F University, Yangling, Shaanxi, 712100, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Cai
authors.affiliation: College of Food Science and Engineering, Northwest A & F University, Yangling, Shaanxi, 712100, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Niu
authors.affiliation: College of Food Science and Engineering, Northwest A & F University, Yangling, Shaanxi, 712100, China.
authors.forename: Tianli
authors.initials: T
authors.lastname: Yue
mesh_terms: D000327:Adsorption; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000378:metabolism*; D007777:Lactobacillaceae / Q000378:metabolism* / Q000648:ultrastructure; D015636:Magnesium Chloride / Q000494:pharmacology; D050296:Microbial Viability / Q000187:drug effects; D010365:Patulin / Q000302:isolation & purification*; D012965:Sodium Chloride / Q000494:pharmacology; D012997:Solvents
chemical_list: D012997:Solvents; D015636:Magnesium Chloride; D019344:Lactic Acid; D012965:Sodium Chloride; D010365:Patulin