1. Department of Chemical Engineering; Kongju National University; Cheonan 31080 Korea
2. Department of Bioenergy Science and Technology; Chonnam National University; Gwangju 61186 Korea
3. Gwangju Institute of Science and Technology (GIST); School of Environmental Science and Engineering; 123 Cheomdan-gwagiro, Buk-gu Gwangju 61005 Korea