Combination Processing Method Reduced IgE-Binding Activity of Litopenaeus vannamei by Modifying Lysine, Arginine, and Cysteine on Multiple Allergen Epitopes.

Allergic reactions occur after the whole food is ingested, rather than the purified allergen. The present study explores the low-allergenic food processing for Litopenaeus vannamei by analysis of macrostructure, digestibility, and immunoreactivity. Furthermore, the presence of modified amino acids on the reported IgE epitopes was analyzed by mass spectrometry. Results showed that the combination processing of Maillard reaction (shrimp meat with galactose) with high temperature-pressure at 115 °C obviously changed the macrostructure and increased the digestibility for the shrimp meat. Meanwhile, the processing significantly reduced the IgG/IgE-binding activity of the shrimp meat. The hypo-IgE-binding activity in processed shrimp may be due to the modification of lysine, arginine, and cysteine residues in antigen epitopes. This is a comprehensive assessment of the specific amino acid residues modified by glycation of multiple allergens in processed L. vannamei, which provides a new research method to explore the hypo-IgE-binding activity in food.

Effects of thermal processing on the allergenicity, structure, and critical epitope amino acids of crab tropomyosin.

Food processing can change the structure and immunoreactivity of purified allergens, but the effect of food processing on the immunoreactivity of the processed and purified allergen is still poorly understood. In this study, tropomyosin (TM) was obtained from Scylla paramamosain and purified after different treatments. A basophil activation test was employed to detect the allergenicity of allergens. The protein structure was detected by mass spectrometry, circular dichroism spectroscopy and surface hydrophobicity. Critical amino acids were identified by Dot blot. Heating obviously affects the biochemical characteristics of TM. The allergenicity of TM was decreased in high temperature-pressure-processed crabs, due to alteration in the protein structure (e.g. denaturation). Seven critical amino acids, namely, R21, E103, E104, E115, A116, E122 and E156, related to the maintenance of the IgE-binding activity of TM were identified. This research of thermal processing helps to accurately reduce or eliminate the immunoreactivity of crabs by food processing.

Channel Crack-Designed Gold@PU Sponge for Highly Elastic Piezoresistive Sensor with Excellent Detectability.

It is a great challenge to fabricate piezoresistive sensors that possess high elasticity, large-area compliance, and excellent detectability to satisfy both extremely tiny and large human activity monitoring. Herein, a novel and facile strategy is reported to manufacture highly elastic channel crack-based gold@PU sponge piezoresistive material. The elastic 3D conductive network is successfully prepared by gold ion sputtering, and channel cracks are skillfully designed on the 3D sponge skeletons. Such novel structure makes these fabricated sensors are capable of monitoring both tiny and large human motions, which originate from the nanocrack joint sensing mechanism and physical contact of conductive interconnected network. Meanwhile, our sensors possess excellent elasticity, fast response time (9 ms), and ultralow detection limit (0.568 Pa), as well as good reproducibility over 1000 cycles. The desirable elasticity of channel crack-based gold@PU sensor is comparable to recently reported pressure sensors, together with advantages of reliable fabrication and large-area compliance, makes them attractive in various electronic devices, for example, biological health monitoring, sport performance monitoring, and man-machine interfaces.