Topochemical investigation of early stages of lignin modification within individual cell wall layers of Scots pine (Pinus sylvestris L.) sapwood infected by the brown-rot fungus Antrodia vaillantii (DC.: Fr.) Ryv.

► Basic topochemical UMSP investigations on brown-rot degraded wood. ► Lignin modification starts at the outermost part of the secondary wall layer. ► Lignin modification occurs before any mass loss is detectable. ► Depolymerisation of the native ligno-cellulosic matrix causes increase in UV absorbance.