[1] Chonnam Natl Univ, Dept Chem, Kwangju 500757, South Korea
[2] Korea Food & Drug Adm, Seoul 122704, South Korea
[3] Dongshin Univ, Dept Korean Med Supply, Naju 520714, South Korea
[4] Nankai Univ, Inst Polymer Chem, Tianjin 300071, Peoples R China