ABSTRACT
Cellulose is the most abundant renewable polymer on Earth, accounting for about 50% of the bound carbon. About 1011 tons are synthesized yearly (1,2), by plants, algae (for example, Valonia), some animals (tunicates), and enzymatically by some bacteria (for example, Acetobacter xylinum). Plants are quantitatively the most important source of cellulose. The chemical composition of plants depends on species but also varies between individual plants of the same species and between different anatomical parts of the same plant. Factors that may influence the chemical composition of a particular plant are, for example, age, place of growth, climate, and harvesting time of the year. The cellulose content of some natural fiber sources is shown in Table 1. Because there often is a lack of information regarding the sample, sampling, and analytical procedure, it is clearly impossible to review absolute figures of reported cellulose content. Thus, the figures shown in Table 1 should only be regarded as guidelines.
