title: Evaluation of Kluyveromyces marxianus FII 510700 grown on a lactose-based medium as a source of a natural bioemulsifier.
abstract: Mannoprotein with emulsification properties was extracted from the cell walls of Kluyveromyces marxianus grown on a lactose-based medium by autoclaving cells in a citrate buffer at pH 7. The purified product was evaluated for chemical and physical stability to establish its potential use as a natural emulsifier in processed foods. The yield of purified bioemulsifier from this strain of K. marxianus was 4-7% of the original dry cell weight. The purified product, at a concentration of 12 g l(-1), formed emulsions that were stable for 3 months when subjected to a range of pH (3-11) and NaCl concentrations (2-50 g l(-1)). The composition of this mannoprotein was 90% carbohydrate (mannan) and 4-6% protein. These values are similar to mannoprotein extracted from cells of Saccharomyces cerevisiae, which is the traditional source. Consequently K. marxianus cultivated on a low-cost lactose-based medium such as whey, a lactose-rich clean waste of the dairy industry, could be developed as a source of bioemulsifier for use in the food industry.
authors.affiliation: School of Civil and Environmental Engineering, The University of New South Wales, 2052 Sydney, Australia. t.lukondeh@unsw.edu.au
authors.forename: Tredwell
authors.initials: T
authors.lastname: Lukondeh
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Ashbolt
authors.forename: Peter L
authors.initials: PL
authors.lastname: Rogers
mesh_terms: D050260:Carbohydrate Metabolism; D003470:Culture Media / Q000378:metabolism; D045703:Emulsifying Agents / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D019649:Food Industry; D006863:Hydrogen-Ion Concentration; D007218:Industrial Microbiology; D007716:Kluyveromyces / Q000254:growth & development* / Q000378:metabolism*; D007785:Lactose / Q000378:metabolism*; D008894:Milk Proteins / Q000378:metabolism; D008970:Molecular Weight; D011506:Proteins / Q000378:metabolism; D012965:Sodium Chloride; D000067816:Whey Proteins
chemical_list: D003470:Culture Media; D045703:Emulsifying Agents; D008894:Milk Proteins; D011506:Proteins; D000067816:Whey Proteins; D012965:Sodium Chloride; D007785:Lactose