Minimally invasive evaluation of cellulose paper degradation using water-soluble carbohydrates

In this study, aqueous extracts of cotton linter paper and Hanji, which is a Korean traditional paper, were analyzed to evaluate the deterioration of paper cultural heritage. We quantified cello-oligosaccharides, which are water-soluble low-molecular-weight carbohydrates, in extracts from the two types of paper. The degree of polymerization (DP) of aged paper was also evaluated based on the absolute molecular weight of cellulose. The content of water-soluble cello-oligosaccharides (COS) varied according to the degree of cellulose degradation. Therefore, the cellulose hydrolysis rate could be predicted from the linear relationship between the cellulose hydrolysis rate and the water-soluble COS content. The DP calculated using the predicted cellulose hydrolysis rate was accurate if the amount of cello-oligosaccharides extracted exceeded the limit of quantification of COS. Consequently, among the many minimally invasive methods available, this methodology may provide an indirect method to evaluate cellulose degradation by quantifying the carbohydrates dissolved in extracts of cotton linter paper and Hanji.

Automated summary

In this study, we analyzed aqueous extracts of cotton linter paper and Hanji to assess the deterioration of paper cultural heritage. Cello-oligosaccharides, water-soluble low-molecular-weight carbohydrates, were quantified in the paper extracts. The degree of polymerization of aged paper was evaluated based on the absolute molecular weight of cellulose. The content of water-soluble cello-oligosaccharides varied with cellulose degradation, and a linear relationship was found between cellulose hydrolysis rate and water-soluble cello-oligosaccharides content.