SPSFAM ERP

Figure 2. Linearity of inulin, levan and agave fructan determination using the K- FRUC assay procedure. The inulin and levan used were 98% pure (w/w, dry weight basis), while agave fructan was 82% pure (w/w, dry weight basis). 6.2.2 Selectivity The Fructan Assay Kit method (K-FRUC) is specific for fructan (inulin, FOS, branched fructans and levan) if performed as described. Under incubation conditions similar to those employed in the K-FRUC assay procedure (same enzyme concentration, but with fructan concentration ~ 40-fold higher than used in the assay) the mixture of endo -inulinase, endo -levanase and exo -inulinase employed gave complete hydrolysis of inulin, FOS, levan and branched fructan (agave) to fructose and glucose ( Figure 3 ). Samples of Raftilose ® , Neosugars ® , agave fructan and Timothy levan were analyzed by HPLC by gel permeation chromatography using TSKgel ® G2500PW XL columns, both before and after incubation with the fructanase mixture as used in the Fructan Assay Kit assay procedure. Clearly, each of the fructans was completely hydrolyzed to fructose and glucose within 20 min.

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