Aspergillus oryzae

Aspergillus ocraceus Aspergillus oryzae Aspergillus parasiticus Aspergillusrugulosus Aspergillus sydowi Aspergillus terreus... 

Benzyl-, phenoxymethyl-and other penicillins N-Deacylation 6-APA and the corresponding acyl side chains Escherichia coli Fusarium semitectum Penidllium chrysogenum Aspergillus oryzae Nine different bacteria... 

To develop a continuous process, the immobilisation of aminoacylase of Aspergillus oryzae by a variety of methods was studied, for example ionic binding to DEAE-Sephadex, covalent binding to iodo-acetyl cellulose and entrapment in polyacrylamide gel. Ionic binding to DEAE-Sephadex was chosen because the method of preparation was easy, activity was high and stable, and regeneration was possible. 

In all the reported examples, the enzyme selectivity was affected by the solvent used, but the stereochemical preference remained the same. However, in some specific cases it was found that it was also possible to invert the hydrolases enantioselectivity. The first report was again from iQibanov s group, which described the transesterification of the model compound (13) with n-propanol. As shown in Table 1.6, the enantiopreference of an Aspergillus oryzae protease shifted from the (l)- to the (D)-enantiomer by moving from acetonitrile to CCI4 [30]. Similar observations on the inversion of enantioselectivity by switching from one solvent to another were later reported by other authors [31]. 

Enzymes PPL, lipase from Pseudomonas fluorescens F-AP, lipase from Rhizopus orizae AP-6, lipase from Aspergillus niger, SP-254, lipase from Aspergillus oryzae P-2, Chirazyme WCPC, whole cell cultures of Penicillium citrinum WCPFL, whole cell cultures of Pseudomona fluorescens CAL-B, lipase from Candida antarctica B PS-C, lipase from Pseudomonas cepacia GCL, lipase from Geotrichum candidum. n.r. not reported. 

Takasuga T, Senthilkumar K, Takemori H, Ohi E, Tsuji H, Nagayama J (2004) Impact of fermented brown rice with Aspergillus oryzae (FEBRA) intake and concentrations of polybrominated diphenylethers (PBDEs) in blood of humans from Japan. Chemosphere 57 795-811... 

An alternative to extraction crystallization is used to obtain a desired enantiomer after asymmetric hydrolysis by Evonik Industries. In such a way, L-amino acids for infusion solutions or as intermediates for pharmaceuticals are prepared [35,36]. For example, non-proteinogenic amino acids like L-norvaline or L-norleucine are possible products. The racemic A-acteyl-amino acid is converted by acylase 1 from Aspergillus oryzae to yield the enantiopure L-amino acid, acetic acid and the unconverted substrate (Figure 4.7). The product recovery is achieved by crystallization, benefiting from the low solubility of the product. The product mixture is filtrated by an ultrafiltration membrane and the unconverted acetyl-amino acid is reracemized in a subsequent step. The product yield is 80% and the enantiomeric excess 99.5%. 

Geiser D M, Domer J W, Horn B W, and Taylor J W (2000), The phylogenetics of mycotoxin and sclerotium production in Aspergillus flavus and Aspergillus oryzae , Fungal Genet. Biol., 31, 169-179. 

Kojic acid was first reported by Saito,2 who isolated it as a crystalline substance from the mycelia of Aspergillus oryzae grown on steamed rice. Yabuta coined the name of the compound (from koji = steamed rice), and by systematic study3 4 gathered enough evidence to propose two... 

Fischer, brilliant results were achieved, and in succession the a-amylases of pig pancreas, of Bacillus subtilis, of human saliva, of human pancreas, and of Aspergillus oryzae, and the /3-amylase of malt, were successfully crystallized. Important biological deductions were gained from this study whereas the amylases of human pancreas and saliva cannot be distinguished from one another, amylases from pig pancreas and from human pancreas are different. These differences are manifested in molecular weight, crystalline forms, electrophoretic mobility, and influence of the pH on the activity however, all the amylases have the same specific biochemical action. The identity of the enzymes seems to be dependent on the species and not on the organ. Interest in biologically active proteins led Meyer to a study of the protein hormones, a field in which he was very active at the time of his death. 

Following Mosher s report, several publications appeared showing the preparation of Mosher s acid. One example is the chemoenzymatic preparation of Mosher s acid using Aspergillus oryzae protease (Scheme 1-5)24 ... 

Aspergillus oryzae protease Scheme 1-5. Chemoenzymatic preparation of Mosher s acid. 

While alpha amylases from many sources are known, the present discussion will deal mainly with the alpha amylase of malted barley, pancreatic amylase and the amylase of Aspergillus oryzae. These... 

Even after extensive purification, the amylase of Aspergillus oryzae is relatively stable in aqueous solutions held at ordinary room temperature. Its lability increases with increasing temperatures and becomes very rapid between 50° and 60°. This loss of activity may be retarded by the presence of substrate and by the presence of calcium ions.4070... 

The amylase of Aspergillus oryzae is most active in slightly acid solutions. When reacting in the presence of 0.01 M acetate at 40° it is most active71 at pH 5.0. 

The amylase of Aspergillus oryzae causes a very rapid decrease in the viscosity of its substrates and a very rapid disappearance from its reaction mixtures of products which give color with iodine. When examined under favorable conditions71 at 40° with Lintner s soluble potato starch, the achroic point was reached with highly purified maltase-free amylase when approximately 12% of the glucose linkages of the substrate had been ruptured. 

When measured at 40° with Lintner s soluble potato starch, the ratio of the dextrinogenic to the saccharogenic activities is approximately 6 to 1 for the amylase of Aspergillus oryzae. This value is given by both crude and purified preparations of the amylase if the measurements are carried out under comparable conditions. This constancy in the ratio of these two activities has led to the conclusion that, like pancreatic amylase, the amylase of Aspergillus oryzae is not accompanied in nature by beta amylase. Reacting mixtures of the amylase of Aspergillus oryzae and starch exhibit alpha mutarotation.72... 

The data show that the extent of the hydrolysis of starch by the amylase of Aspergillus oryzae depends within wide limits upon the concentration of amylase used. Like those for pancreatic amylase already discussed (Figure 2), these hydrolysis curves show a change from a rapid to a slow phase of the reaction and tend to flatten at higher values as the concentration of amylase is increased. Again, with different concentrations of the amylase of Aspergillus oryzae there is no evidence of a common limit such as is observed with different concentrations of beta amylase (Figure 1). 

A Comparison of the Hydrolysis of Soluble Potato Starch by Purified Maltase-free Pancreatic Amylase or Amylase of Aspergillus oryzae (Extent of Hydrolysis as Percent Theoretical Maltose)... 

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