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Amylase Inhibitor (amylase + inhibitor)
Selected AbstractsComparison of conventional FASTA identity searches with the 80 amino acid sliding window FASTA search for the elucidation of potential identities to known allergensMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 8 2007Gregory S. Ladics Abstract Food and Agriculture Organization/World Health Organization (FAO/WHO) recommended that IgE cross-reactivity between a transgenic protein and allergen be considered when there is ,F 35% identity over a sliding "window" of 80 amino acids. Our objective was to evaluate the false positive and negative rates observed using the FAO/WHO versus conventional FASTA analyses. Data used as queries against allergen databases and analyzed to assess false positive rates included: 1102 hypothetical corn ORFs; 907 randomly selected proteins; 89 randomly selected corn proteins; and 97 corn seed proteins. To evaluate false negative rates of both methods: Bet v 1a along with several crossreacting fruit/vegetable allergens and a bean ,-amylase inhibitor were used as queries. Both methods were also evaluated for their ability to detect a putative nonallergenic test protein containing a sequence derived from Ara h 1. FASTA versions 3.3t0 and 3.4t25 were utilized. Data indicate a conventional FASTA analysis produced fewer false positives and equivalent false negative rates. Conventional FASTA versus sliding window derived E scores were generally more significant. Results suggest a conventional FASTA search provides more relevant identity to the query protein and better reflects the functional similarities between proteins. It is recommended that the conventional FASTA analysis be conducted to compare identities of proteins to allergens. [source] Host-mediated induction of ,-amylases by larvae of the Mexican bean weevil Zabrotes subfasciatus (Coleoptera: Chrysomelidae: Bruchinae) is irreversible and observed from the initiation of the feeding periodARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 4 2010Thaís D. Bifano Abstract Larvae of Zabrotes subfasciatus secrete , -amylases that are insensitive to the , -amylase inhibitor found in seeds of Phaseolus vulgaris. By analyzing amylase activities during larval development on P. vulgaris, we detected activity of the constitutive amylase and the two inducible amylase isoforms at all stages. When larvae were transferred from the non , -amylase inhibitor containing seeds of Vigna unguiculata to P. vulgaris, the inducible , -amylases were expressed at the same level as in control larvae fed on P. vulgaris. Interestingly, when larvae were transferred from seeds of P. vulgaris to those of V. unguiculata, inducible , -amylases continued to be expressed at a level similar to that found in control larvae fed P. vulgaris continuously. When 10-day-old larvae were removed from seeds of V. unguiculata and transferred into capsules containing flour of P. vulgaris cotyledons, and thus maintained until completing 17 days (age when the larvae stopped feeding), we could detect higher activity of the inducible , -amylases. However, when larvae of the same age were transferred from P. vulgaris into capsules containing flour of V. unguiculata, the inducible , -amylases remained up-regulated. These results suggest that the larvae of Z. subfasciatus have the ability to induce insensitive amylases early in their development. A short period of feeding on P. vulgaris cotyledon flour was sufficient to irreversibly induce the inducible , -amylase isoforms. Incubations of brush border membrane vesicles with the , -amylase inhibitor 1 from P. vulgaris suggest that the inhibitor is recognized by putative receptors found in the midgut microvillar membranes. © 2010 Wiley Periodicals, Inc. [source] The effect of wheat ,-amylase inhibitors incorporated into wheat-based artificial diets on development of Sitophilus granarius L., Tribolium confusum Duv., and Ephestia kuehniella ZellJOURNAL OF APPLIED ENTOMOLOGY, Issue 4 2002J. R. Warchalewski Artificial grain kernels made from ground wheat grain, commercial wheat starch and wheat proteinaceous ,-amylase inhibitors were used as diets for adults of the granary weevil (Sitophilus granarius L). For the confused flour beetle (Tribolium confusum Duv.) and the Mediterranean flour moth (Ephesitia kuehniella Zell.), a friable mixture of the diets was used. The results of feeding trials showed that the survival of S. granarius adults was not correlated with the soluble proteins extracted from wheat and amylolytic activity located in this protein fraction. On the other hand, the weight of dust (the index of feeding intensity) produced during feeding depended on the presence of ,-amylase and trypsin inhibitors in wheat-based diets. Ephesitia kuehniella larvae did not develop at all on a diet consisting of 50% wheat starch and 50% crude ,-amylase inhibitors from wheat. The same diet lengthened the development time of T. confusum larvae by 15.1 days. These results attest to the existence of a specific native enzymatic apparatus in the alimentary canals of these three grain pests. However, the highly active insect ,-amylase inhibitors appear to have a limited influence on the developmental parameters studied although some reduction of insects populations might be expected. [source] Nutritional Quality of Drum-processed and Extruded Composite Supplementary FoodsJOURNAL OF FOOD SCIENCE, Issue 2 2005Theobald C.E. Mosha ABSTRACT: This study was conducted to evaluate the nutritional quality of ready-to-eat composite foods intended for supplementary feeding of preschool age children in Tanzania. Four supplementary foods, namely, corn-bean-sardine meal (CBSM), bean meal (BM), sorghum-bean-sardine meal (SBSM), and rice-bean-sardine meal (RBSM) were formulated according to the FAO/WHO/UNU guidelines. The food mixtures were extruded, drum-processed, and cooked conventionally in the traditional way. Cooking doneness was evaluated by percent starch gelatinization and residual urease activity; biological qualities,true protein digestibility and growth performance,were evaluated using Sprague Dawley weanling rats. Efficiency in destroying phytohemagglutinins and the antinutritional factors, trypsin, chymotrypsin, and ,-amylase inhibitors, were also evaluated. Results of the study showed that starch gelatinization and residual urease activity were not significantly different (P > 0.05) between the extruded and drum-processed diets. Relative to conventional cooking, starch gelatinization was 95% to 100% in extruded and 90% to 100% in drum-processed products. Inactivation of urease activity ranged from 93% to 100% in extruded and 83% to 100% in drum-processed diets. The true protein digestibilities were significantly (P, 0.05) higher when extruded foods, compared with drum-processed and conventionally cooked foods, were fed to experimental animals. Animals fed extruded products gained more weight relative to those fed drum-processed and conventionally cooked foods. Destruction of phytohemagglutinins ranged between 91% to 97% in extruded and between 90% to 95% in the conventionally cooked and drum-processed foods. Extrusion, drum processing, and conventional cooking also resulted in significant destruction of the antinutritional factors trypsin, chymotrypsin, and a-amylase inhibitors. These results suggest that extrusion and drum processing of cereal-bean-sardine composite foods result in products meeting the required nutritional quality. [source] | |||||||||||||