Rapid Characterization of Trace Aflatoxin B1 on Groundnuts, wheat and maize by Dispersive Liquid‐Liquid Microextraction Followed by Direct Electrospray Probe Tandem Mass Spectrometry.
RATIONALE: Aflatoxins are poisonous and cancer-related chemical compounds commonly existed in crops and plants. Aflatoxin B1 is the most toxic compound among aflatoxins and has been classified as Group 1 carcinogenic to human, especially on liver cancer. Herein, an ambient mass spectrometric method was developed for rapid characterization of trace aflatoxin B1 on peanuts. METHODS: Direct electrospray probe tandem mass spectrometry was used to detect aflatoxin B1 on peanuts. To avoid the matrix effect, the aflatoxin B1 in the samples was extracted and concentrated by dispersive liquid-liquid microextraction. The mass spectrometer was operated in the positive ion mode to monitor intact molecular ion (m/z 313, MH+ ) and daughter ion (m/z 241) of aflatoxin B1 using multiple reaction monitoring. RESULTS: Since no clean up procedure of the sample was required, the sampling step, and the subsequent mass spectrometric detection of the aflatoxin B1 was completed less than 5 minutes. The limit-of-detection of aflatoxin B1 is at sub-ppb level. The results obtained by direct electrospray probe tandem mass spectrometry were also validated by liquid chromatography-tandem mass spectrometry. Recovery of aflatoxin B1 in the sample was evaluated by analyzing spiked aflatoxin B1 with liquid chromatography-tandem mass spectrometry to be 85% and direct electrospray probe tandem mass spectrometry to be 84%. CONCLUSION: The direct electrospray probe tandem mass spectrometry combined with a simple dispersive liquid-liquid microextraction procedure was successfully used for the quantitative analysis of AFB1 in nut samples. Due to its highly efficient feature, it is promising in providing important toxicological information for food safety in real world.
Mediterranean Diet Improves High-Density Lipoprotein Function in High-Cardiovascular-Risk Individuals: A Randomized Controlled Trial.
BACKGROUND: The biological functions of high-density lipoproteins (HDLs) contribute to explaining the cardioprotective role of the lipoprotein beyond quantitative HDL cholesterol levels. A few small-scale interventions with a single antioxidant have improved some HDL functions. However, to date, no long-term, large-scale, randomized controlled trial has been conducted to assess the effects of an antioxidant-rich dietary pattern (such as a traditional Mediterranean diet [TMD]) on HDL function in humans. METHODS: This study was performed in a random subsample of volunteers from the PREDIMED Study (Prevención con Dieta Mediterránea; n=296) after a 1-year intervention. We compared the effects of 2 TMDs, one enriched with virgin olive oil (TMD-VOO; n=100) and the other enriched with nuts (TMD-Nuts; n=100), with respect to a low-fat control diet (n=96). We assessed the effects of both TMDs on the role of HDL particles on reverse cholesterol transport (cholesterol efflux capacity, HDL ability to esterify cholesterol, and cholesteryl ester transfer protein activity), HDL antioxidant properties (paraoxonase-1 arylesterase activity and total HDL antioxidant capacity on low-density lipoproteins), and HDL vasodilatory capacity (HDL ability to induce the release of nitric oxide in endothelial cells). We also studied the effects of a TMD on several HDL quality-related characteristics (HDL particle oxidation, resistance against oxidative modification, main lipid and protein composition, and size distribution). RESULTS: Both TMDs increased cholesterol efflux capacity relative to baseline (P=0.018 and P=0.013 for TMD-VOO and TMD-Nuts, respectively). The TMD-VOO intervention decreased cholesteryl ester transfer protein activity (relative to baseline, P=0.028) and increased HDL ability to esterify cholesterol, paraoxonase-1 arylesterase activity, and HDL vasodilatory capacity (relative to control, P=0.039, P=0.012, and P=0.026, respectively). Adherence to a TMD induced these beneficial changes by improving HDL oxidative status and composition. The 3 diets increased the percentage of large HDL particles (relative to baseline, P<0.001). CONCLUSIONS: The TMD, especially when enriched with virgin olive oil, improved HDL atheroprotective functions in humans.
Endurance Exercise Increases Intestinal Uptake of the Peanut Allergen Ara h 6 after Peanut Consumption in Humans.
Controlled studies on the effect of exercise on intestinal uptake of protein are scarce and underlying mechanisms largely unclear. We studied the uptake of the major allergen Ara h 6 following peanut consumption in an exercise model and compared this with changes in markers of intestinal permeability and integrity. Ten overnight-fasted healthy non-allergic men (n = 4) and women (n = 6) (23 ± 4 years) ingested 100 g of peanuts together with a lactulose/rhamnose (L/R) solution, followed by rest or by 60 min cycling at 70% of their maximal workload. Significantly higher, though variable, levels of Ara h 6 in serum were found during exercise compared to rest (Peak p = 0.03; area under the curve p = 0.006), with individual fold changes ranging from no increase to an increase of over 150-fold in the uptake of Ara h 6. Similarly, uptake of lactulose (2-18 fold change, p = 0.0009) and L/R ratios (0.4-7.9 fold change, p = 0.04) were significantly increased which indicates an increase in intestinal permeability. Intestinal permeability and uptake of Ara h 6 were strongly correlated (r = 0.77, p < 0.0001 for lactulose and Ara h 6). Endurance exercise after consumption may lead to increased paracellular intestinal uptake of food proteins.
Enhanced Prophylactic and Therapeutic Effects of Polylysine-Modified Ara h 2 DNA Vaccine in a Mouse Model of Peanut Allergy.
BACKGROUND: The prevalence of food allergy has been increasing, but treatment is very limited. DNA vaccination has been recognized as a promising method for the treatment of allergic diseases; however, poor immunogenicity has hindered its application. METHODS: BALB/c mice were intradermally injected with plasmid DNA encoding the peanut protein Ara h 2 (pAra h 2) or pAra h 2 pretreated with poly-L- lysine (PLL) before or after sensitization with Ara h 2 protein. Ara h 2-specific antibodies were measured by ELISA. CD207+ dendritic cells (DCs) and Treg cells in draining lymph nodes were analyzed by flow cytometry after DNA immunization, and cytokine production in splenocytes was also analyzed. RESULTS: In the prophylactic study, pretreatment with pAra h 2 or PLL-pAra h 2 resulted in lower levels of Ara h 2-specific IgG1, IgG2a, and IgE after sensitization with Ara h 2 protein, and mice in the PLL-pAra h 2 group had a significantly lower level of antibodies than those in the pAra h 2 group. In the treatment study, intradermal injection with pAra h 2 or PLL-pAra h 2 after Ara h 2 protein sensitization significantly decreased the level of Ara h 2-specific antibodies, and PLL- pAra h 2 had stronger effects than pAra h 2. There were increased numbers of CD207+ DCs and Treg cells in the mice receiving intradermal injection with PLL-pAra h 2, and splenocytes from PLL-pAra h 2-treated mice secreted increased levels of IFN-γ and IL-10. CONCLUSIONS: Modification of pAra h 2 with PLL improved its prophylactic and therapeutic effects in peanut-allergic mice.
Threshold Dose Distribution in Walnut Allergy.
BACKGROUND: In food allergy, eliciting doses (EDs) of foods on a population level can improve risk management and labeling strategies for the food industry and regulatory authorities. Previously, data available for walnut were unsuitable to determine EDs. OBJECTIVE: The objective of this study was to determine EDs for walnut allergic adults and to compare with previously established threshold data for peanut and tree nuts. METHODS: Prospectively, adult subjects with a suspected walnut allergy underwent a low-dose double-blind, placebo-controlled food challenge. Individual no observed and lowest observed adverse effect levels were determined and log-normal, log-logistic, and Weibull models were fit to the data. Estimated ED values were calculated for the ED5, ED10, and ED50, the dose respectively predicted to provoke an allergic reaction in 5%, 10%, and 50% of the walnut allergic population. RESULTS: Fifty-seven subjects were challenged and 33 subjects were confirmed to be walnut allergic. Objective symptoms occurred in 20 of the positive challenges (61%). The cumulative EDs in the distribution models ranged from 3.1 to 4.1 mg for the ED05, from 10.6 to 14.6 mg walnut protein for the ED10, and from 590 to 625 mg of walnut protein for the ED50. CONCLUSIONS: Our data indicate that population EDs for walnut are slightly higher compared with those for peanut and hazelnut allergy. Currently available data indicate that the ED values for hazelnut could be used as a conservative temporary placeholder when implementing risk management strategies for other tree nuts where little or no food challenge data are available.
The National Institutes of Allergy and Infectious Diseases sponsored guidelines on preventing peanut allergy: A new paradigm in food allergy prevention.
Peanut allergy is a significant public health problem without proven treatment or cure at present. In 2000, the American Academy of Pediatrics recommended that solid-food introduction be delayed in infants at high risk, including peanut introduction, until age 3 years. In 2008, the American Academy of Pediatrics revised these recommendations based on limited evidence of benefit and, instead, recommended solid-food introduction not be delayed past 4-6 months of life. In 2015, the Learning Early About Peanut Allergy study showed that early peanut introduction (between 4 and 11 months of life) was associated with a significant absolute and relative risk reduction in the development of peanut allergy compared with delayed introduction. Based on these findings, the National Institutes of Allergy and Infectious Diseases sponsored an expert panel to create an addendum to the 2010 Food Allergy Guidelines that specifically focuses on peanut allergy prevention. The addendum recommends that children with severe eczema, egg allergy, or both have peanut introduced as early as 4-6 months of life, after assessment by a trained allergy specialist. For children with mild-to-moderate eczema, peanut can be introduced at 6 months, without the need for specialist evaluation. For children with no eczema, peanut can be introduced in accordance with family and cultural preferences, without the need for specialist evaluation. Adherence to these clinical practice recommendations can help potentially reduce the number of cases of peanut allergy per year. However, this can only be accomplished with the cooperation of parents and health care providers who adhere to these recommendations.
Addendum guidelines for the prevention of peanut allergy in the United States: Report of the National Institute of Allergy and Infectious Diseases–sponsored expert panel.
BACKGROUND: Food allergy is an important public health problem because it affects children and adults, can be severe and even life-threatening, and may be increasing in prevalence. Beginning in 2008, the National Institute of Allergy and Infectious Diseases, working with other organizations and advocacy groups, led the development of the first clinical guidelines for the diagnosis and management of food allergy. A recent landmark clinical trial and other emerging data suggest that peanut allergy can be prevented through introduction of peanut-containing foods beginning in infancy. OBJECTIVES: Prompted by these findings, along with 25 professional organizations, federal agencies, and patient advocacy groups, the National Institute of Allergy and Infectious Diseases facilitated development of addendum guidelines to specifically address the prevention of peanut allergy. RESULTS: The addendum provides 3 separate guidelines for infants at various risk levels for the development of peanut allergy and is intended for use by a wide variety of health care providers. Topics addressed include the definition of risk categories, appropriate use of testing (specific IgE measurement, skin prick tests, and oral food challenges), and the timing and approaches for introduction of peanut-containing foods in the health care provider's office or at home. The addendum guidelines provide the background, rationale, and strength of evidence for each recommendation. CONCLUSIONS: Guidelines have been developed for early introduction of peanut-containing foods into the diets of infants at various risk levels for peanut allergy.
Guidelines for Children With Peanut Allergy.
The number of children with peanut allergy has increased dramatically over the past 20 years. Parents may be particularly concerned about peanut allergy because most food-related serious allergic reactions, such as anaphylaxis, a severe allergic reaction that includes breathing difficulties as well as fatal allergic reactions, are associated with peanuts. Because peanut allergy is common and can be quite serious, many parents want guidelines for how to best prevent allergies to peanuts. Many research studies over the past 20 years have focused on peanut allergy and how best to prevent it. This research has been translated into guidelines for families that are mostly focused on what time in a child’s life is safest to introduce peanuts into the diet. With new research emerging, these guidelines have been updated to represent the best available evidence from research. An article in this month’s JAMA Pediatrics reviews these guidelines and the research studies that informed the guidelines.
Food Targeting: Geographical origin determination of hazelnuts (Corylus avellana) by LC-QqQ-MS/MS based targeted metabolomics application.
A targeted metabolomics LC-ESI-QqQ-MS application for geographical origin discrimination based on 20 non-polar key metabolites was developed, validated according to accepted guidelines and used for quantitation via stable isotope labeled internal standards in 202 raw authentic hazelnut samples from six countries (Turkey, Italy, Georgia, Spain, France and Germany) out of harvest years 2014 and 2015. Multivariate statistics were used for detection of significant variations in metabolite levels between countries and moreover, a prediction model using support vector machine classification (SVM) was calculated yielding 100% training accuracy and 97% cross-validation accuracy which was subsequently applied to 55 hazelnut samples for confectionary industry gaining up to 80% correct classifications compared to declared origin. The present method demonstrates the great suitability for targeted metabolomics applications in geographical origin determination of hazelnuts and their applicability in routine analytics.
Effect of Almond Supplementation on Glycemia and Cardiovascular Risk Factors in Asian Indians in North India with Type 2 Diabetes Mellitus: A 24-Week Study.
BACKGROUND: Type 2 diabetes (T2D) statistics have reached menacing proportions in India. Appropriate dietary intervention, as part of healthy lifestyle, is imperative to curb further spread of this disease. OBJECTIVES: This pre-post intervention study was conducted in New Delhi, India, to investigate the effects of daily consumption of almonds for 24 weeks in T2D subjects, specifically on measures of glycemia and cardiovascular disease (CVD) risk factors. METHODS AND STUDY DESIGN: In this study, the 24-week intervention period was preceded by a control diet and exercise run-in period of 3 weeks. Raw almonds (20% of energy intake) were provided to the patients for consumption along with diet and physical activity counseling. Patients were assessed for anthropometry, blood pressure, measures of glycemia (fasting blood glucose, glycosylated hemoglobin), lipids [total cholesterol (TC), triglycerides, high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol, lipoprotein(a)], surrogate marker of atherosclerosis (Pulse wave velocity), and marker of inflammation (high sensitivity C-reactive protein [hs-CRP]) at baseline and after the intervention period. RESULTS: Statistically significant improvement in mean values for various parameters post intervention was as follows: waist circumference (P < 0.03), waist-to-height ratio (P < 0.005), TC (P < 0.002), serum triglycerides (P < 0.004), low-density lipoprotein cholesterol (P < 0.01), glycosylated hemoglobin (P < 0.04), and hs-CRP (P < 0.01). A trend toward improvement in pulse wave velocity (P < 0.06) was also observed. CONCLUSION: The study findings illustrate that incorporation of almonds in a well-balanced healthy diet leads to multiple beneficial effects on glycemic and CVDs risk factors in Asian Indian patients with T2D.