Enzymatic treatment, change

Fig. 3. Schematic of teratogenicity screening assay. Fertilized eggs are collected within a few hours of spawning. The chorions can be removed by gentle enzymatic treatment with manual removal as needed. The embryos are then cultured for the desired period of time. When embryos are incubated in 1 ml of medium, continuous exposure (without medium changes) is possible for at least 5 days. Embryos are exposed to the test substance in the culture medium. At the desired timepoint(s) (e.g., 5 dpt), larvae can be evaluated for viability and developmental parameters. (Reprinted from Brannen et al. (4), by permission of John Wiley and Sons.).

Table XI. Change in Pore Volume of Linters Powder Samples by Enzymatic Treatment (Cellulase G, 68 hr/40°C, 1%)...

Since the last symposium there have been several changes in attitudes or directions. One of these has been the recognition that alkali treatment of proteins is a chemical procedure, and in particular, a chemical modification. Another has been the recognition that, although there are still difficult problems in assessing the safety aspects of chemical modifications of foods, both chemical and enzymatic treatments can be useful in laboratory experimentation and, perhaps, in eventual application to food production. Increase in nutritional value through modifications is now recognized. 

Physicochemical Changes on Wool Surface after an Enzymatic Treatment... 

The amount of the individual amino acids released during the enzymatic treatment of wool was monitored by the HPLC method. Moreover, an XPS analysis of enzymatic-modified wool fabric samples and contact angle measurements were performed. The data obtained by the XPS method allowed comparison of the changes in the elemental concentration on the wool surface after enzymatic treatment. The results of the contact angle measurements demonstrated an increase in the wettability of the modified wool surfaces. 

Fig. 4 Changes in the PCD potential during the enzymatic treatment of wool (4% o.w.f. of Perizym LAN)...

Also, the enzymatic treatment causes a change in the isoelectric point (IEP) value of wool, as demonstrated by the electrokinetic measurements (Fig. 5). With an increase in enzyme concentration the IEP value shifts in the direction of more acidic pH (from 3.8 for untreated wool to 3.7 for wool after 1% enzymatic treatment, and 3.45 for wool... 

Most likely the changes in IEP value, as well as in PCD potential, during the enzymatic treatment of wool are the result of enzyme-initiated oxidation reactions. As can be seen from the XPS results specified below (Table 1), a slight increase in SO2, SO3, SO4 groups concentration, from 0.248% (0.248%= 11.8% of 2.1% of total elemental concentration) for untreated sample to 0.314% (0.314% = 19.6% of 1.6% of total elemental concentration) can be observed. 

The data obtained by the XPS method (Table 1, Fig. 7) show the changes in the elemental concentration of C, N, S, and 0 on the wool surface after enzymatic treatment, as compared to untreated wool. The increase in the atomic concentration of carbon, from 78.6% for untreated wool to 79.4% for wool after enzymatic treatment, and the decrease in the atomic concentration of nitrogen from 6.5% for untreated wool to 5.3% for wool after enzymatic... 

Changes in the topography of wool fibres, confirmed by SEM micrographs, can be observed as a result of the enzymatic treatment of wool fabric. 

The investigation of the biological/functional activities of soy trypsin inhibitors showed unexpected results (Fig. 8). While BBI activity did not change during the enzymatic treatments, KTI activity was significantly reduced in the peptic hydrolysate and EPM product of soy albumin. 

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