title: Characteristics of sugar surfactants in stabilizing proteins during freeze-thawing and freeze-drying.
abstract: Sugar surfactants with different alkyl chain lengths and sugar head groups were compared for their protein-stabilizing effect during freeze-thawing and freeze-drying. Six enzymes, different in terms of tolerance against inactivation because of freeze-thawing and freeze-drying, were used as model proteins. The enzyme activities that remained after freeze-thawing and freeze-drying in the presence of a sugar surfactant were measured for different types and concentrations of sugar surfactants. Sugar surfactants stabilized all of the tested enzymes both during freeze-thawing and freeze-drying, and a one or two order higher amount of added sugar surfactant was required for achieving protein stabilization during freeze-drying than for the cryoprotection. The comprehensive comparison showed that the C10-C12 esters of sucrose or trehalose were the most effective through the freeze-drying process: the remaining enzyme activities after freeze-thawing and freeze-drying increased at the sugar ester concentrations of 1-10 and 10-100 μM, respectively, and increased to a greater extent than for the other surfactants at higher concentrations. Results also indicate that, when a decent amount of sugar was also added, the protein-stabilizing effect of a small amount of sugar ester through the freeze-drying process could be enhanced.
authors.affiliation: Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan.
authors.forename: Koreyoshi
authors.initials: K
authors.lastname: Imamura
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Murai
authors.forename: Tamayo
authors.initials: T
authors.lastname: Korehisa
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Shimizu
authors.forename: Ryo
authors.initials: R
authors.lastname: Yamahira
authors.forename: Tsutashi
authors.initials: T
authors.lastname: Matsuura
authors.forename: Hiroko
authors.initials: H
authors.lastname: Tada
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Imanaka
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Ishida
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Nakanishi
mesh_terms: D002241:Carbohydrates / Q000737:chemistry*; D005612:Freeze Drying; D005615:Freezing; D011506:Proteins / Q000737:chemistry*; D013501:Surface-Active Agents / Q000737:chemistry*
chemical_list: D002241:Carbohydrates; D011506:Proteins; D013501:Surface-Active Agents
keywords: enzymes; freeze-drying; freeze-thawing; freeze-tolerance; interaction; stabilization; sugar surfactant; surfactants