1. Department of Biomedical Science, University of Sassari, Sassari, Italy;
2. Department of Chemistry, Hue University of Sciences, Hue University, Hue City, ThuaThien Hue Province, Vietnam;
3. Department of Biochemistry, Hue University of Medicine and Pharmacy, Hue City, ThuaThien Hue Province, Vietnam;
4. Department of Microbiology and Carlo Urbany Center, Hue University of Medicine and Pharmacy, Hue City, ThuaThien Hue Province, Vietnam;
5. C.N.R. - Istituto di Chimica Biomolecolare, Sassari, Italy;
6. Department of Chemistry and Pharmacy, University of Sassari, Sassari, Italy