Cellulolytic Biodegradation of Cotton Fibers from A Deep-Ocean Environment

Items of clothing recovered after 133 years of submersion at a deep-ocean shipwreck site provided a unique source of marine-degraded textiles. In this research, both dyed and undyed cotton samples taken from a man's waistcoat were studied by optical and scanning electron microscopy and by energy dispersive x-ray spectroscopy. The undyed fibers showed features typical of localized biodegradation, and two different forms of cellulolytic micro-organisms were observed. Black deposits, perhaps formed by sulfate-reducing bacteria, were observed on both the dyed and undyed samples. After treatment with a mixture of sodium hydroxide plus carbon disulfide, fibrillation and horizontal fragmentation of the dyed and undyed cotton fibers, respectively, were observed. In contrast, new cotton samples treated similarly with sodium hydroxide and carbon disulfide formed the “balloons” typical of fibers with intact primary walls. Tin was present only in the dyed sample. Its source is probably a mordant used in the dyeing process. It is likely that the tin aided in protecting the fabric from attack by cellulolytic micro-organisms.