Monitoring of acrylamide carcinogen in selected heat-treated foods from Saudi Arabia.
The present study reports the outcomes of assessment on acrylamide levels in selected heat-treated foods of diverse brands and origins from Saudi Arabia. In chips, acrylamide level was detected from 28 to 954 µg/kg, sample 7 (salted) contained higher amount (954 μg/kg) whereas, sample 8 (labneh and mint) comparatively produced lower amount (28 μg/kg). Nuts and dried fruits have generated acrylamide from 2 to 93 µg/kg, salted peanut of Indian origin produced higher amount (93 μg/kg) while apricot (plain) relatively generated lower amount (2 μg/kg). The levels of acrylamide in biscuits, pastry, cacao, chocolate, olive, cheese, corn, oat and wheat flakes, and bread were found from 26 to 234 µg/kg. Biscuits generated high concentration (234 μg/kg) while corn flakes fairly generated lower amount (26 μg/kg). The obtained results have shown a great variation of acrylamide content and reason might be due to foods type, cooking ingredients and, cooking methods, time and temperature.
Prevalence and Concentration of Salmonella on Raw, Shelled Peanuts in the United States.
Recalls and outbreaks associated with Salmonella contamination in peanut-containing products have been reported over the past several years. Very limited data existed on the prevalence and concentration of Salmonella on raw, shelled peanuts in the United States. An initial study was completed in 2012 to estimate the prevalence and concentration of Salmonella on Runner- and Virginia-type raw, shelled peanuts in the United States from the 2008 through 2011 crop years, which were proportionately sampled from each growing region based on 2007 production volume. That study was extended to include samples of Runner- and Virginia-type peanuts from 2013, 2014, and 2015 crop years proportionately sampled from each growing region on the basis of the 2008 through 2010 volumes. Of the total 2,506 raw, shelled peanutsamples, 41 (1.63%) were positive for Salmonella by the VIDAS SLM assay. Salmonella serovars identified in this study included Agona, Anatum, Bardo, Braenderup, Cannstatt, Dessau, Gaminara, Litchfield, Hartford, Inverness, Mbandaka, Meleagridis, Muenchen, Newport, Pakistan, Rodepoort, Rubislaw, Tennessee, and Tornow. The concentration levels of Salmonella in positive samples, as determined by most probable number (MPN), ranged from <0.003 to 2.4 MPN/g. These data will be useful when designing and validating processes for the reduction or elimination of Salmonella in peanuts or peanut-containing products or both.
Elucidation of the Amygdalin Pathway Reveals the Metabolic Basis of Bitter and Sweet Almonds (Prunus dulcis).
Almond (Prunus dulcis) is the principal Prunus species in which the consumed and thus commercially important part of the fruit is the kernel. As a result of continued selection, the vast majority of almonds have a non-bitter sweet kernel. However, in the field there are trees carrying bitter kernels, which are toxic to humans and, consequently, need to be removed. The toxicity of bitter almonds is caused by accumulation of the cyanogenic diglucoside amygdalin, which releases toxic hydrogen cyanide upon hydrolysis. In this study, we identified and characterized the enzymes involved in the amygdalin biosynthetic pathway: PdCYP79D16 and PdCYP71AN24 as the cytochrome P450 (CYP) enzymes catalyzing phenylalanine to mandelonitrile conversion, PdUGT94AF3 as an additional monoglucosyl transferase (UGT) catalyzing prunasin formation, and PdUGT94AF1 and PdUGT94AF2 as the two enzymes catalyzing amygdalin formation from prunasin. Here, this was accomplished by constructing a sequence database containing UGTs known, or prospected to catalyse a β(1→6)-O glycosylation reaction, and a BLAST search of the draft version of the almond genome versus these sequences. Functional characterization of candidate genes was achieved by transient expression in Nicotiana benthamiana. Reverse transcription quantitative PCR demonstrated that the expression of PdCYP79D16 and PdCYP71AN24 was not detectable or only reached minute levels in the sweet almond genotype during fruit development, while it was high and consistent in the bitter genotype. Therefore, the basis for the sweet kernel phenotype is a lack of expression of the genes encoding the two cytochrome P450s catalyzing the first steps in amygdalin biosynthesis.
Characterizing Brown Marmorated Stink Bug Injury in Almond, a New Host Crop in California.
The brown marmorated stink bug, Halyomorpha halys (Stål), is an invasive species from Asia. This polyphagous, stink bug species has posed a serious production challenge in several crop species in the areas where established. The insect has spread to all the mainland states in the U.S. in about one and half decades after its first detection in Pennsylvania. The types of crops reported to have been infested by this stink bug have increased with its spread to new geographic locations. In this study, we report the first evidence of H. halys infestation in almond fruit in California. In Stanislaus County, an adult brown marmorated stink bug in an almond orchard was first observed in May 2017. The stink bug feeding on almond fruits caused excessive gumming to the developing fruits, and damage to the kernels along with typical necrotic feeding signs on the shell (endocarp) and hull (exocarp and pericarp) of the fruit at harvest. The infestation and damage by H. halyson almond warrants further research to develop Integrated Pest Management (IPM) strategies for this pest. https://doi.org/10.3390/insects9040126
Adjuvanted Immunotherapy Approaches for Peanut Allergy.
Food allergies are a growing public health concern with an estimated 8% of US children affected. Peanut allergies are also on the rise and often do not spontaneously resolve, leaving individuals at-risk for potentially life-threatening anaphylaxis throughout their lifetime. Currently, two forms of peanut immunotherapy, oral immunotherapy (OIT) and epicutaneous immunotherapy (EPIT), are in Phase III clinical trials and have shown promise to induce desensitization in many subjects. However, there are several limitations with OIT and EPIT, such as allergic side effects, daily dosing requirements, and the infrequent outcome of long-term tolerance. Next-generation therapies for peanut allergy should aim to overcome these limitations, which may be achievable with adjuvanted immunotherapy. An adjuvant can be defined as anything that enhances, accelerates, or modifies an immune response to a particular antigen. Adjuvants may allow for lower doses of antigen to be given leading to decreased side effects; may only need to be administered every few weeks or months rather than daily exposures; and may induce a long-lasting protective effect. In this review article, we highlight examples of adjuvants and formulations that have shown pre-clinical efficacy in treating peanut allergy.
Genetic Diversity Between Mouse Strains Allows Identification of CC027/GeniUnc as an Orally Reactive Model of Peanut Allergy.
BACKGROUND: Improved animal models are needed to understand the genetic and environmental factors that contribute to food allergy. OBJECTIVE: Assess food allergy phenotypes in a genetically diverse collection of mice. METHODS: We selected 16 Collaborative Cross (CC) mouse strains, as well as the classic inbred C57BL/6J, C3H/HeJ, and BALB/cJ strains for screening. Female mice were sensitized to peanut intragastrically with or without Cholera toxin, then challenged with peanut by oral gavage or intraperitoneal injection, and assessed for anaphylaxis. Peanut-specific immunoglobulins, T cell cytokines, Tregs, mast cells, and basophils were quantified. RESULTS: Eleven of the 16 CC strains had allergic reactions to intraperitoneal peanut challenge, whereas only CC027/GeniUnc mice reproducibly experienced severe symptoms following oral food challenge (OFC). CC027/GeniUnc, C3H/HeJ, and C57BL/6J all mounted a Th2 response against peanut, leading to the production of IL-4 and IgE but only the CC027/GeniUnc mice reacted to OFC. Orally-induced anaphylaxis in CC027/GeniUnc mice was correlated with serum levels of Ara h 2 in circulation, but not with allergen-specific IgE or MMCP-1 levels, indicating systemic allergen absorption is important for anaphylaxis through the gastrointestinal tract. Furthermore, CC027/GeniUnc mice, but not C3H/HeJ or BALB/cJ, can be sensitized in the absence of Cholera toxin and react upon OFC to peanut. CONCLUSIONS:
We have identified and characterized CC027/GeniUnc mice as a strain that is genetically susceptible to peanut allergy and prone to severe reactions following OFC. More broadly, these findings demonstrate the untapped potential of the CC population in developing novel models for allergy research.
Oral peanut immunotherapy‐How much is too much? How much is enough?.
Efficacy of Food allergy immunotherapy (FA-AIT) for cow's milk, hen's egg and peanut at the level of desensitization is established via several small placebo-controlled trials and a number of open label trials1 . First approved treatments for peanut allergy are projected to become available soon including oral immunotherapy (OIT). But there is still a discussion which group of patients might profit most of OIT and what amount of maintenance dose to apply.
Ara h 1 and Ara h 6 Sensitization Causes Clinical Peanut Allergy in Ara h 2-Negative Individuals.
BACKGROUND: Of the major peanut allergens, sensitivity to Ara h 2 has the highest prediction for clinical allergy. In this study, we evaluated sensitization to peanut components in Iceland and related Ara h 2-negative sensitization to clinical allergy. METHODS: Ara h 1, Ara h 2, Ara h 3, Ara h 8, and Bet v 1 IgEs were measured (ImmunoCAP) in 220 peanut IgE (Pn-IgE)-positive serum samples. Ara h 2 IgE-negative individuals were invited to an open peanut challenge and evaluated for Ara h 6 and 9 sensitization (ISAC microarray). RESULTS: The Ara h 2 IgE-negative group (52.3%, 115/220) was older (p = 0.04) and more likely to have a history of pollen allergy than the Ara h 2-positive group (p < 0.001). Of the Ara h 2-negative participants, 24.3% were already consuming peanuts and 38.3% were unavailable. Of the 43 who underwent an open peanut challenge, 79% were negative, 14% were positive, and 7% were inconclusive. Those who reacted to peanuts had a higher Ara h 1 IgE than that of the tolerant participants, and 3 were positive to Ara h 6 IgE, and 2 of those subjects were monosensitized. Ara h 8 may have caused a positive reaction, while Ara h 9 did not. CONCLUSIONS: Half of the peanut-sensitized individuals in Iceland were not sensitized to the major allergen Ara h 2. Ara h 1, Ara h 3, and Ara h 6 sensitizations resulted in a positive open peanut challenge and they are therefore clinically important for individuals with a peanut allergy in Iceland.
Boiling and roasting treatment affecting the peanut allergenicity.
BACKGROUND: Peanut allergy appears to be less prevalent in other parts of the world than North America and several European countries, and it has been proposed difference in cooking practices may be responsible. In this study, the boiling and roasting processes were investigated to find a potential method to enhanced or reduce the allergenicity. METHODS: The allergenicity of different peanut products, as reflected by changes in ethology (diarrhea and weight loss) and pathology (splenomegaly and jejunum breakage) were observed, and relevant serological indexes were determined after feeding different peanut products. Different peanut proteins were used to analyze the ability to resistance digestion in simulated gastric fluid (SGF). Ultraviolet spectrum and CD spectra were used to analyze structure changes of Ara h 2 in roasting and boiling treatment. RESULTS: In the detection of the corresponding serological indicators, boiled peanuts show a lower sensitization than roasted and raw peanuts. SGF experiments demonstrated an increased resistance of roasted peanut protein to digestion. The results of ultraviolet spectrum and CD spectra showed that the roasting and boiling causes altered structures of the Ara h 2 peanut allergens. CONCLUSIONS: The summary show that different thermal processing may affect the structure and immunoreactivity, and the sensitization of roasted or boiled peanuts will be enhanced or reduced.
IgE Cross-Reactivity of Cashew Nut Allergens.
BACKGROUND: Allergic sensitisation towards cashew nut often happens without a clear history of eating cashew nut. IgE cross-reactivity between cashew and pistachio nut is well described; however, the ability of cashew nut-specific IgE to cross-react to common tree nut species and other Anacardiaceae, like mango, pink peppercorn, or sumac is largely unknown. OBJECTIVES: Cashew nut allergic individuals may cross-react to foods that are phylogenetically related to cashew. We aimed to determine IgE cross-sensitisation and cross-reactivity profiles in cashew nut-sensitised subjects, towards botanically related proteins of other Anacardiaceae family members and related tree nut species. METHOD: Sera from children with a suspected cashew nut allergy (n = 56) were assessed for IgE sensitisation to common tree nuts, mango, pink peppercorn, and sumac using dot blot technique. Allergen cross-reactivity patterns between Anacardiaceae species were subsequently examined by SDS-PAGE and immunoblot inhibition, and IgE-reactive allergens were identified by LC-MS/MS. RESULTS: From the 56 subjects analysed, 36 were positive on dot blot for cashew nut (63%). Of these, 50% were mono-sensitised to cashew nuts, 19% were co-sensitised to Anacardiaceae species, and 31% were co-sensitised to tree nuts. Subjects co-sensitised to Anacardiaceae species displayed a different allergen recognition pattern than subjects sensitised to common tree nuts. In pink peppercorn, putative albumin- and legumin-type seed storage proteins were found to cross-react with serum of cashew nut-sensitised subjects in vitro. In addition, a putative luminal binding protein was identified, which, among others, may be involved in cross-reactivity between several Anacardiaceae species. CONCLUSIONS: Results demonstrate the in vitro presence of IgE cross-sensitisation in children towards multiple Anacardiaceae species. In this study, putative novel allergens were identified in cashew, pistachio, and pink peppercorn, which may pose factors that underlie the observed cross-sensitivity to these species. The clinical relevance of this widespread cross-sensitisation is unknown.