| Autor: |
Reginald Charles Matheson Lance, DE Evans, W. Wallace, L. C. MacLeod |
| Rok vydání: |
1997 |
| Předmět: |
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| Zdroj: |
Journal of Cereal Science. 26:241-250 |
| ISSN: |
0733-5210 |
| Popis: |
The level ofbeta-amylase in germinating barley grain and the kilned malt has been examined by assaying for activity, quantitative ELISA and immunoblotting using antibodies specific tobeta-amylase. During germination there is a substantial increase in combinedbeta-amylase activity; the sum ofbeta-amylase soluble in aqueous salt solutions and that extracted in the presence of β-mercaptoethanol (ME). Although previous studies have attributed this increase to activation ofbeta-amylase, here we report that the increase in activity is matched by an increase in the level of combinedbeta-amylase protein as measured by ELISA. Most, if not all, of this additional activebeta-amylase protein is made available by the release ofbeta-amylase from a newly described latent fraction between day 1 and 4 of germination. The latent fraction is extractable with a solution of 1% sodium dodecyl sulphate and 1% ME. Assessment of barley grain and malt from commercial maltsters has confirmed that similar increases in combinedbeta-amylase activity occur in commercial malt houses. Kilning results in up to a 46% reduction inbeta-amylase activity which is associated with a similar reduction in the level ofbeta-amylase protein measured by ELISA. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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