Determination of Total Available Carbohydrates in Plants

The estimation of carbohydrates plays an important part in both pure and applied plant physiology. While satisfactory methods of extracting and determining the individual types of carbohydrates are available, the complete fractionation of these is a tedious process. Furthermore, for many purposes of a more applied nature the determination of the total available carbohydrate content is of greater significance than that of individual carbohydrates or groups of carbohydrates. The term "total available carbohydrate" may be defined as including all those carbohydrates which can be used in the plant body as a source of energy or as building material, either directly or indirectly after having been broken down by enzymes. In most ordinary, higher green plants the bulk of available carbohydrate is composed of sugars, fructosans, dextrin and starch, whereas hemicelluloses and true cellulose act merely as structural materials and as such cannot further be utilized in the same way as