Immunoglobulin E and immunoglobulin G cross-reactive allergens and epitopes between cow milk alpha(S1)-casein and soybean proteins
JOURNAL OF DAIRY SCIENCE
Authors: Cong, Yanjun; Li, Ye; Li, Linfeng
Abstract
Some infants allergic to cow milk based formula are also sensitive to soybean-based formula. This paper aimed to explore the association of IgE and IgG cross-reactivity between alpha(S1)-casein in cow milk (CM) and soybean proteins. The IgE and IgG cross-reactive allergens and epitopes were identified using sera from infants allergic to CM or mice monoclonal antibodies. The AA sequence alignment was performed using bioinformatics software. Finally, the digestion and heating stability of the cross-reactive allergen were explored by sodium dodecyl sulfate (SDS)-PAGE and Western blotting. The results showed that the IgE and IgG cross-reactive allergen was alpha subunit of beta-conglycinin named Gly rn Bd 60K. The IgE and IgG epitopes were the sequences at AA 319-341 and AA 164-182. No intact Gly m Bd 60K allergen could be observed after 2 min in simulated gastric fluid by SDS-PAGE. Heating did riot change IgE and IgG cross-reactivity by Western blotting. Therefore, the existence of cross-reactivity between CM alpha(S1)-casein and soybean proteins possibly contributes to the frequently observed cosensitization for these allergens in cow milk-allergic patients. The same IgE- and IgG-binding epitopes of cross-reactive allergens may provide important information for elucidation of the association between IgG and IgE antibody generation.
Three phase partitioning for simultaneous extraction of oil, protein and polysaccharide from rice bran
INNOVATIVE FOOD SCIENCE & EMERGING TECHNOLOGIES
Authors: Wang, Hong; Geng, Haoyuan; Chen, Jun; Wang, Xu; Li, Dan; Wang, Tong; Yu, Dianyu; Wang, Liqi
Abstract
Three phase partitioning (TPP) technique was used to extract oil, protein and polysaccharides simultaneously from rice bran. The fatty acid composition of rice bran oil (RBO) and structure of rice bran protein (RBP) and rice bran polysaccharides (RBPS) were analyzed. Under the optimal conditions of (NH4)(2)SO4 concentration 28% (w/v), slurry to t-butanol ratio 1:1.1 (v/v), pH 5.10, extraction temperature 40 degrees C and extraction time 1 h, the highest extraction yields of RBO, RBP and RBPS were 17.28%, 6.81% and 2.09%, respectively. The fatty acid composition of RBO was analyzed by GC, the structure of RBP was analyzed by FTIR and SDS-PAGE, and the structure of RBPS was analyzed by FTIR. The results were similar to those obtained by other methods. Therefore, TPP can be used as an effective technology for simultaneous extraction of oil, protein and polysaccharide from rice bran.