INVESTIGATION OF ENZYMATIC EFFECTS ON PIT MEMBRANES USING LIGHT AND SCANNING ELECTRON MICROSCOPY

Spruce wood is one of the refractory wood species. Pit membranes, which provide liquid flow between the wood cells, have an influence on the permeability of wood. However, these membranes tend to close under the fibre saturation point (FSP), which makes the impregnation process more difficult. In this study, spruce sapwood samples were treated with two different commercial enzymes to improve their permeability. Bioprep 3000 L and Viscozyme L, which are mostly used in the textile industry, are alkaline pectinase enzymes and acidic pectinase enzymes respectively. Following enzymatic treatment, mass losses in the wood samples were observed and the wood samples were analysed with light microscopy (LM) and scanning electron microscopy (SEM). The mass losses of the wood samples were less than 2%. All enzyme treated and untreated wood samples were stained with toluidine blue. The pectin material was coloured red with toluidine blue stain. However; enzymatic treatment caused the loss of red coloration along with the expansion and rupturing of the pit membranes. These results showed that the pit membranes were destroyed.