Probing palaeoclimatology through quantitation by mass spectrometry of the products of enzyme hydrolysis of α-cellulose

Abstract

It is shown that quantitative measurement of the saccharides from enzymatic hydrolysis of α-cellulose extracted from individual annual tree-rings has the potential to provide insight into the ecosystem in which the tree grew. The quantitative measurement reported here, which is the first of its kind, concerned the complex of cellulases Trichoderma Reesei and α-cellulose samples from annual tree-rings of Pinus sylvestris L for the period 1968–2000. Monosaccharides were measured using electrospray mass spectrometry. There were significant differences among concentrations of monosaccharide from different annual tree-rings. We attribute these variations to structural differences in the α-cellulose. The hypothesis put forward is that higher concentrations of monosaccharide reflect higher degrees of crystallinity. The concentrations of monosaccharide correlated positively with annual precipitation; the concentrations did not correlate with other climate indicators. It is pointed out that the widths of annual tree-rings are known to correlate positively with these other climate indicators, but not with annual precipitation.