Amylases properties

Somewhat analogous to these rice products is Oatrim, a material based on oat flour. It was developed at the Northern Laboratory of the USDA and is offered commercially by several firms. Oatrim contains 5% proteia, 5% P-glucan, 2% pentosans, and 83% maltodextrias. Unique properties are claimed based on the P-glucan component, and preparation of Oatrim is disclosed ia USDA pubHcations and patents. Briefly, oat flour is broken down by a-amylase, then the water-soluble component is dried and is the product of commerce, aimed at ground meat product usage. 

The function of Jisper Uis fermentation appears to be primarily the breakdown of protein and polysaccharides by secreted proteases and amylases. Replacement oiPispergillis by chemical or enzymatic hydrolysis has no major impact on the organoleptic properties of the sauce. Likewise, inoculation with a pure culture of Ixictobacillus delbrueckii to carry out the acetic acid fermentation produces a normal product. The S. rouxii and Toru/opsis yeasts, however, are specifically required for proper flavor development. 

The stability of the enzyme-polymer complex and its dissociation upon the variation of pH depends on the structural and other physico-chemical properties of CP and enzyme molecule. Thus, a Biocarb-T heteroreticular biosorbent (Fig. 26) is characterized by a stability of its complex with ot-amylase (under the condition of its stabilization) in acid solutions and a complete dissociation of the complex during isolation of the active enzyme at pH 7-8. 

Separation of human a-amylase isoenzymes by electrofo-cusing and their immunological properties. Clin. Chim. Acta (1975), 60, 207-213. 

A product manufactured in Japan as Alo mixture (Anomalously Linked Oligosaccharides) contains mainly a range of IMOS (glucose, isomaltose, and panose as principal constituents). It is produced from starch as substrate by the action of alpha-amylase, beta-amylase, and a transglucosidase. It is claimed to have favorable properties for application in the food industry.143... 

In this chapter we describe the use of pea seeds to express the bacterial enzyme a-amylase. Bacterial exoenzymes like the heat stable a-amylase from Bacillus licheni-formis are important for starch hydrolysis in the food industry. The enzymatic properties of a-amylase are well understood [13,14], it is one of the most thermostable enzymes in nature and it is the most commonly used enzyme in biotechnological processes. Although fermentation in bacteria allows highly efficient enzyme production, plant-based synthesis allows in situ enzymatic activity to degrade endogenous reserve starch, as shown in experiments with non-crop plants performed under greenhouse conditions [12,15]. Finally, the quantitative and sensitive detection of a-amylase activ-... 

No attempt is made here to survey the extensive literature on amylases. A number of recent reviews have discussed the general nature and properties of these enzymes1-6 and this report will be devoted mainly to a summary of our present information about the action of some of the alpha amylases. 

No attempt is made in this chapter to review in detail our present information concerning the beta amylases. However, because it is impossible to consider adequately the properties of the alpha amylases without reference to beta amylases, it seems desirable to describe briefly a few of the characteristic properties of the beta amylases. 

If amylases are to be used as tools for the detailed study of the breakdown and structure of their substrates it is obviously important to separate them from other enzymes and from other naturally associated constituents which may influence the results. It is then equally important to study the properties of the purified amylase and to supply it with the chemical environment necessary to protect it from inactivation and to enable it to act efficiently. With beta amylases this ideal has often been approached. Beta amylases from several sources have been prepared by selective inactivation of other enzymes that accompany them in nature23 and highly active products have been obtained by extensive purification.20 24-26 Balls and his associates have recently reported the crystallization of beta amylase from sweet potato.27... 

This paper will review our studies on 1) B-amylase of C. thermosulfUrogenes 2) a-glucosidase of C. thermohydrosulfuricum 3) glucose isomerase of C. thermosulfurogenes and Thermoanaerohacter strain B6A and, 4) endoxylanase of Thermoanaerohacter strain B6A. A separate paper by Saha et al., in this symposium, will report on the properties of the novel pullulanase present in these thermoanaerobes. 

J. J. Marshall and C. M. Lauda, Purification and properties of phaseolamin, an inhibitor of a-amylase, from the kidney bean, Phaseolus vulgaris, J. Biol. Chem., 250 (1975) 8030-8037. 

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