Affiliations: Department of Food Science and Technology, School of
Agricultural Biotechnology, Seoul National University, Seoul 151-742, South
Korea | Department of Food and Biotechnology, Korea
University, Chochiwon, Chungnam 339-700, South Korea | Lipozen Inc., Pyong Taek 451-822, South Korea
Note: [] Address for correspondence: Professor Hyong Joo Lee, Department
of Food Science and Technology, Seoul National University, Shinlim-dong,
Kwanak-ku, Seoul 151-742, South Korea. Tel.: +82 2 880 4853; Fax: +82 2 873
5095; E-mail: [email protected]
Abstract: The application of conjugated linoleic acid (CLA) as a functional
food ingredient has been limited due to its high cost of purification and
insolubility in water. Recently, we reported a method to produce high-purity
CLA using two-step urea-inclusion crystallization and a hydrophilic
arginine-CLA (Arg-CLA) complex. The present study compared the oxidative
stability and antioxidant activity of CLA and Arg-CLA. Hydroperoxide production
from CLA increased about 12-fold at 10 hr after heat treatment at 100®C,
whereas Arg-CLA did not exhibit significant hydroperoxide production.
Furthermore, the Arg-CLA complex showed synergistic antioxidant activity in a
2,2'-azinobis(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) radical scavenging
assay. Arg-CLA at 20 mM scavenged 89% of ABTS radicals in 3 h, whereas CLA
alone quenched only 48% under the same conditions. Our results indicate that a
hydrophilic Arg-CLA exhibits enhanced oxidative stability and antioxidant
activity, which could expand the scope of CLA application in various food
industries.
