Impact of cold plasma processing on major peanut allergens

Abstract

Cold plasma is emerging as a novel food processing technology, with demonstrated efficacies for microbial inactivation and residual chemical dissipation of food products. Given the technology’s multimodal action it has the potential to reduce allergens in foods, however data on the efficacy and mechanisms of action are sparse. This study investigates the efficacy of cold plasma on major peanut allergens (Ara h 1 and Ara h 2). For this purpose, dry, whole peanut (WP) and defatted peanut flour (DPF) were subjected to an atmospheric air discharge using a pin to plate cold plasma reactor for different treatment durations. With increases in plasma exposure, SDS-PAGE analysis revealed reduced protein solubility of the major peanut allergens. Alterations in allergenicity and structure of Ara h 1 and Ara h 2 were examined using ELISA and circular dichroism (CD) spectroscopy. Competitive ELISA with proteins purified from plasma treated WP or DPF revealed reduced antigenicity for both Ara h 1 and Ara h 2. The highest reduction in antigenicity was 65% for Ara h 1 and 66% Ara h 2 when purified from DPF. Results from CD spectroscopy analysis of purified proteins strongly suggests the reduction in antigenicity is due to modifications in the secondary structure of the allergens induced by plasma reactive species. Cold plasma is effective at reducing peanut protein solubility and causes changes in allergen structure leading to reduced antigenicity.

Effect of dielectric barrier discharge (DBD) plasma on the activity and structural changes of horseradish peroxidase

“…The intensity of HRP bands decreased in a time-dependent manner after DBD plasma treatment (Figure 4A). These data are consistent with previous findings (Ng et al, 2020;Venkataratnam et al, 2020). For instance, SDS-PAGE analysis indicated that the band intensity of casein declined dramatically with an increasing treatment time of spark discharge and glow discharge plasma (Ng et al, 2020).…”

“…For instance, SDS-PAGE analysis indicated that the band intensity of casein declined dramatically with an increasing treatment time of spark discharge and glow discharge plasma (Ng et al, 2020). Similar findings were also reported by Venkataratnam et al (2020), who found that cold plasma caused degradation of Ara h1 and Ara h2 with SDS-PAGE, two major peanut allergens. The decrease in band intensity following DBD plasma treatment may be due to the oxidative damage of HRP.…”

Cold plasma for the disinfection of industrial food‐contact surfaces: An overview of current status and opportunities

“…Many studies have utilized CAP for the decontamination of (bio)chemical contaminants, such as mycotoxins from fungi (Wielogorska et al., 2019; Hojnik, Modic, Tavčar‐Kalcher et al., 2019; Hojnik et al., 2017), prions (Elmoualij et al., 2012; Shintani, 2012; Baxter et al., 2005), proteins and enzymes (Laroussi, 2018; Misra, Pankaj, Segat et al., 2016; Takai et al., 2014), allergens (Ng et al., 2021; Venkataratnam et al., 2020; Venkataratnam et al., 2019; Ekezie et al., 2018; Meinlschmidt et al., 2016), and pesticides (Toyokawa et al., 2018; Misra, Pankaj et al., 2014).…”

Peanut allergen induces more serious allergic reactions than other allergens involving MAPK signaling pathways

“…This is consistent with prior reports in the literature that have demonstrated that a peanut allergen reaction is often the most severe, and is the leading cause of deadly anaphylaxis. 36 Additionally, egg, soybean and milk allergies were relatively mild compared to peanut allergy. AllerCatPro (https://allercatpro.bii.a-star.edu.sg/ ) was used to predict the potential allergenicity of the proteins and it was found that allergenicity was associated with the epitopes (these data are provided in the ESI †).…”