Summary
Amylase activity in extracts of sprouted tubers was optimised at final concentrations of soluble starch in the incubation medium of 0.6–2.0 mg cm−3. Optimum pH was 6. The exclusion of calcium ions from extraction and incubation media did not result in reduced enzyme activity. This, together with a shift in the absorption maximum of the starch-iodine complex almost identical to that observed with pure β-amylase, indicates the predominance of β-amylase in the extracts. Over a 15-min incubation period the linearity of the response was dependent upon the volume of tuber extract included in the assay medium. Gel filtration of extracts did not influence this response.
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Ross, H.A., Davies, H.V. Amylase activity in potato tubers. Potato Res 30, 675–678 (1987). https://doi.org/10.1007/BF02367647
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DOI: https://doi.org/10.1007/BF02367647