Investigation on the Anaphylaxis and Anti-Digestive Stable Peptides Identification of Ultrasound-Treated α-Lactalbumin during In-Vitro Gastroduodenal Digestion

Abstract

Our previous studies indicated that ultrasound treatment can increase the anaphylaxis of protein. However, investigation on the anaphylaxis changes of ultrasound-treated α-lactalbumin (ALA) during digestion is lacking. The anaphylaxis of ultrasound-treated ALA and its digesta was investigated. The anti-digestive stable peptides were identified by high-resolution mass spectrometry. Ultrasound induced the tertiary structure of ALA to unfold and increased its anaphylaxis. During digestion, the anaphylaxis of both gastric and gastroduodenal digesta was further increased. There are two reasons for this phenomenon. On the one hand, linear epitopes played an important role in affecting anaphylaxis compared with the conformational epitope, and some linear epitopes were still retained on the anti-digestive stable peptides produced after gastroduodenal digestion, resulting in increased anaphylaxis after digestion. On the other hand, the presence of intact ALA molecules after digestion still remained strong anaphylaxis. Compared with the digesta of untreated ALA, the digesta of ultrasound-treated ALA possessed higher anaphylaxis. The results indicated that ultrasound increased the anaphylaxis of ALA during digestion.

Gastrointestinal fate of food allergens and its relationship with allergenicity

“…Moreover, tomato peel/pulp nsLTP (Sola l 3) showed increased immunoreactivity after gastrointestinal digestion with an IgE‐binding value of 185% compared to the undigested protein, suggesting that the partial unfolding of Sola l 3 under acidic gastric conditions might unmask IgE epitopes (Martín‐Pedraza et al., 2021). Similar results have been described for α‐lactalbumin, where some linear epitopes retained on the antidigestive stable peptides were exposed after gastroduodenal digestion and played a more important role in triggering allergic reactions than conformational epitopes, resulting in increased allergenicity after digestion (X. Wang, Tu, Liu, et al., 2021).…”

Purification, Immunological Identification, and Characterization of the Novel Silkworm Pupae Allergen Bombyx mori Lipoprotein 3 (Bomb m 6)

“…In contrast, IgE reactivity was increased by SIF digestion for 10, 20, 30, and 150 min (Figure H) and by SGIF digestion for 150 min (Figure I), possibly because digestion exposes new IgE-specific antigenic epitopes as the protein structure unfolds. Similar results have been reported for α-Lactalbumin, which lost IgG reactivity after 30 min of SIF digestion and 5 min of SGIF digestion, indicating that the IgG-binding epitope was more susceptible to trypsin cleavage than the IgE-binding epitope.…”

Effects of Sargassum thunbergii Extract on Skin Whitening and Anti-Wrinkling through Inhibition of TRP-1 and MMPs

“…Among the conventional extraction processes, ultrasound-assisted extraction (UAE) is particularly attractive due to its simplicity, low equipment cost, high extraction yield from different matrices, low energy consumption, a lower amount of solvent required, and less time [ 23 ]. UAE is known to involve high-frequency sound waves of 20–100 kHz [ 24 ]. The extraction yield is enhanced using ultrasound, and this is attributed to the disruption of the plant tissues, reduction in particle size, and increased mass transfer of extracts to the solvent caused by the collapse of the bubbles that are produced by repeated acoustic cavitation [ 25 , 26 ].…”