A NOVEL METHOD OF USING INDIGENOUS WOOD ROTTING FUNGI IN LIGNIN DEGRADATION OF TOBACCO STALKS
NYEMBEZI MGOCHEKI *
Biological Sciences Department, Faculty of Science and Engineering, Bindura University of Science Education, P. Bag 1020, Bindura, Zimbabwe.
TANAKA CALVIN MARONGWE
Biological Sciences Department, Faculty of Science and Engineering, Bindura University of Science Education, P. Bag 1020, Bindura, Zimbabwe.
MARUNDA MIKE
Tobacco Research Board (TRB) - Kutsaga Research Station Kutsaga Research Station, Airport Ring Road, P.O.Box-1909, Harare, Zimbabwe.
MUSCLINE GANDA
Tobacco Research Board (TRB) - Kutsaga Research Station Kutsaga Research Station, Airport Ring Road, P.O.Box-1909, Harare, Zimbabwe.
BETTY MAWIRE
Tobacco Research Board (TRB) - Kutsaga Research Station Kutsaga Research Station, Airport Ring Road, P.O.Box-1909, Harare, Zimbabwe.
*Author to whom correspondence should be addressed.
Abstract
Tobacco stalks represent a type of abundant renewable resources whereas wood rotting fungi are of renowned industrial interest. This study was aimed at assessing the biotechnological potentiality of indigenous wood rotting fungi on lignin degradation of tobacco stalks. 21 isolates were isolated and screened for phenol red oxidation in Potato Dextrose Agar (PDA) containing 250 µg/mL phenol. 12 isolates oxidized phenol and were compared on decolorization of five dyes; acid fuchsin, indigo carmine, congo red, methyl orange, and malachite green supplemented independently at 250 µg/mL in PDA. Further, In vitro studies were carried out on lignin degradation. The isolates were incubated with ground tobacco stalks and final residual lignin content calculated. Isolate 9, 6 and 2 effectively reduced lignin content from 29.15% to 16.26%. 16.72% and 19.22% respectively, suggesting them as a suitable cost effective mechanism that can be considered for use on lignin degradation in Zimbabwe. The fungal isolates 9, 6 and 2 have great biotechnological potential in the paper industries in both dye discoloration and delignification and hence recommended for biotechnological reduction of pollutants from the paper industry.
Keywords: Decolorization, degradation, IWFRI, lignin cellulosic