Studies on Starch‐Degrading Enzymes. Part VIII A Comparison of α‐Amylases from Different Sources: Their Properties and Action Patterns

Greenwood, C. T.; Milne, Elspeth

doi:10.1002/star.19680200502

Cited by 41 publications

(12 citation statements)

References 75 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Purified enzyme preparations have limited stability at mashing temperatures unless protected by neutral protein or by the presence of an excess of substrate.8-21 How ever, the protection normally provided by the mash constituents can be replaced by having an excess of calcium ions in the 10 Enzyme stability was therefore maintained in the starch granule digests by adding sufficient calcium chloride (10-mM) to stabilize the a-amylase over a range of pH values at 65°C (Table III).…”

Section: Resultsmentioning

confidence: 99%

THEIN VIVOANDIN VITRODEGRADATION OF BARLEY AND MALT STARCH GRANULES

Bathgate¹,

Palmer²

1973

Journal of the Institute of Brewing

View full text Add to dashboard Cite

The susceptibilities to amylolytic hydrolysis of the two different types of starch granule in barley and malt have been investigated. The large and small granules from both germinated and ungerminated grain were subjected to the sole action of malt a-amylase under conditions which otherwise simu lated those of a conventional infusion mash.Large starch granules from barley are hydrolysed at a slower rate than those from malt. The faster conversion of the latter is attributed to prior modification of the starch granule structure during germination. The small granules from barley are extremely resistant to attack by a-amylase and even pre-cooking does not appreciably increase their susceptibility to amylase attack. Although the small starch granules from malt are less susceptible than the corresponding large granule fraction, they can be hydrolysed to a greater extent than can the small granules from barley. The increased susceptibility of small granules from malt is probably due to the partial removal of their protecting surface layer of protein.Although during malting the small granules of barley are hydrolysed more rapidly than the large granules, the situation is reversed during mashing. Very little loss of extract can be attributed to the enzymic resistance of small starch granules in all-malt mashes. If raw barley is used in the grist, sub stantial amounts of small starch granules may remain in the mash.

show abstract

Section: Resultsmentioning

confidence: 99%

THEIN VIVOANDIN VITRODEGRADATION OF BARLEY AND MALT STARCH GRANULES

Bathgate¹,

Palmer²

1973

Journal of the Institute of Brewing

View full text Add to dashboard Cite

show abstract

“…2). This histidine residue is required for activity of the enzymes from plants, animals, bacteria and from fungi (Greenwood and Milne, 1968;Kita et al, 1982;Dua and Kochhar, 1985). It is interesting to note that two residues equivalent to Pro 129 and Pro 137 are present in AMY2 isoform in barley and which are substituted by lysine and leucine amino acid in case of AMY1.…”

Section: Substratementioning

confidence: 98%

α-Amylase from germinating soybean (Glycine max) seeds – Purification, characterization and sequential similarity of conserved and catalytic amino acid residues

et al. 2010

View full text Add to dashboard Cite

“…Starch can be separated into amylose, a linear macromolecule and amylopcctin, a branched glycogen-like polymer in proportions depending on the plant from which the starch originates [Deatherage et al, 1955], The ultimate products from com plete «-amylolysis of both components are glucose and maltose [for review : Banks and Greenwood, 1975], the a-amylase of saliva producing predominantly maltose and mal totriose [Greenwood and Milne, 1968;Mormann-Buchmann, 1979]. Despite the fact that a-amylase is present in consider able amounts in human parotid saliva [Ja cobsen et al, 1972], no attempt has been made to quantify the mode and rate of amylolytic hydrolysis of dietary starch in vivo.…”

mentioning

confidence: 99%

Oral Starch Degradation and Its Influence on Acid Production in Human Dental Plaque

Mörmann

Mühlemann²

1981

Caries Res

View full text Add to dashboard Cite

Enzymatic hydrolysis of starch by salivary α-amylase, its time dependence and influence on plaque acid production was investigated. Analysis of the composition of starch digests was performed with gel filtration chromatography. Wheat starch in solution, in bread and in biscuit was hydrolyzed rapidly mainly to maltose, maltotriose and limit dextrins. In vivo enzymatic degradation of wheat starch caused marked drops in interdental plaque pH to 4.75 measured by intraoral plaque pH telemetry, most probably as the result of the fermentation of low molecular weight maltodextrins by plaque bacteria. On this basis starch may contribute to cariogenesis.

show abstract

Studies on Starch‐Degrading Enzymes. Part VIII A Comparison of α‐Amylases from Different Sources: Their Properties and Action Patterns

Cited by 41 publications

References 75 publications

THEIN VIVOANDIN VITRODEGRADATION OF BARLEY AND MALT STARCH GRANULES

THEIN VIVOANDIN VITRODEGRADATION OF BARLEY AND MALT STARCH GRANULES

α-Amylase from germinating soybean (Glycine max) seeds – Purification, characterization and sequential similarity of conserved and catalytic amino acid residues

Oral Starch Degradation and Its Influence on Acid Production in Human Dental Plaque

Contact Info

Product

Resources

About