1. Department of Horticultural Science, University of Minnesota, Saint Paul, Minnesota 55108, United States
2. Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588, United States
3. College of Food Science, Shenyang Agricultural University, Shenyang, Liaoning 110866, China
4. College of Agronomy, Shenyang Agricultural University, Shenyang, Liaoning 110866, China