1. Division
of Agro-Processing Technologies and Industrial Chemistry, Tanzania Industrial Research and Development Organization (TIRDO), P.O. Box 23235, Dar es
Salaam, Tanzania
2. Department
of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Aas, Norway
3. Department
of Chemistry, University of Oslo, P.O. Box 1033, Blindern, N-0315 Oslo, Norway