[1] Univ Alberta, Dept Chem, Edmonton, AB, Canada
[2] Univ British Columbia, Dept Chem, Vancouver, BC V5Z 1M9, Canada
[3] Alberta Res Council, Carbohydrate Res Program, Edmonton, AB, Canada
[4] Univ Maryland, Dept Anim & Avian Sci, College Pk, MD 20742 USA