In vitro lipid digestion in raw and roasted hazelnut particles and oil bodies.
Previous studies have proved that the physical encapsulation of nutrients by the cell walls of plant foods modulates macronutrient bioaccessibility during human digestion. In this study, we investigated structural factors that modulate lipid hydrolysis during in vitro digestion of raw and roasted hazelnut particles and isolated oil bodies. Isolated oil bodies exhibited a significantly higher lipid hydrolysis compared to hazelnut particles. Moreover, roasting had an impact on the structure of hazelnut cell walls implying a more efficient diffusion of digestive fluids and enzymes into the hazelnut cells. Heat treatment also caused destabilization of oil body interfacial protein membranes, facilitating their proteolysis under gastric conditions, altering the emulsion properties and enhancing fatty acid release during intestinal digestion. This study underlined the barrier role played by the plant cell wall as well as the impact of heat processing on lipid bioaccessibility in hazelnuts.
Threshold dose distribution for cashew nut allergy in children.
Allergy to cashew nut in children is increasingly recognized in clinical practice and the prevalence of this allergy seems to increase. Furthermore, previous studies showed the potential for cashew nut to cause anaphylaxis [1]. Despite the increasing prevalence of cashew nut allergy and the severity of the reaction to this allergen, there are only few studies on this allergy, especially on the threshold dose.
Evaluation of the chemical and nutritional characteristics of almonds (Prunus dulcis (Mill). D.A. Webb) as influenced by harvest time and cultivar.
BACKGROUND: Several authors studied the effect of harvest time on chemical and nutritional composition of almonds, but the results are partly conflicting, probably due to differences in the cultivars considered and to different agronomic and climatic conditions in the growing areas. In this paper the influence of harvest time and cultivar on the chemical and nutritional composition of almonds (Prunus dulcis (Mill). D.A. Webb) was evaluated. Ten cultivars were considered, grown in the same orchard and subjected to the same agronomical regime. Almonds were collected at two different harvest times: i) when the fruits were unripe, but already edible, and showed green and moist hull, and ii) when the fruits were ripe, with dry brown hull. The analyses of proximate composition, fatty acid profile, total phenolic compounds and antioxidant activity were carried out. RESULTS: Lipid content increased (p<0.001) during ripening, while both protein and carbohydrate content decreased (p<0.01). Fatty acid composition showed a not univocal behavior during ripening and was highly influenced by cultivar. Total phenolic compounds and antioxidant activity varied among cultivars but increased during ripening with the exception of Marcona cv. Genco and Francolì cvs were found to be phenolic-rich cultivars. CONCLUSION: Harvest time and cultivars significantly influenced the chemical and nutritional composition of almonds. Genotype strongly influenced fatty acid composition and total phenolic compounds. The changes of bioactive compounds and antioxidant activity suggest that the synthesis of antioxidants occur also in the last stage of ripening. Unripe almonds, a valuable niche product, showed interesting nutritional value.
Identification and Characterization of Phenolic Compounds in Black Walnut Kernels.
Black walnuts (Juglans nigra L.) are highly valued for producing phenolic-enriched nuts. The objectives of this study were to identify and characterize the phenolic contents of 11 different black walnut cultivars and compare the levels of these phenolics between black walnuts and English walnut (Juglans regia L.). Totally, 16 phenolics including phenolic acids, flavonoids, and catechins were identified in the black walnut kernels, with ellagic acid predominating over the other phenolics. Significant differences were noted for the levels of quinic acid, gallic acid, 1,3,6-trigalloylglucose, catechin, and penta- O-galloyl-β-d-glucose between the studied black walnuts and English walnut. Through principal component analysis, 51.54% of the variance in the phenolic data was explained. The hierarchical cluster analysis results showed three groups to which each walnut sample belongs. Most of the phenolics identified in this study have been reported to exert potential health-promoting activities. The findings of this study will provide critical information for consumers, nutritional therapy practitioners, researchers, and producers.
Peanut allergens.
Peanut allergens have the potential to negatively impact on the health and quality of life of millions of consumers worldwide. The seeds of the peanut plant Arachis hypogaea contain an array of allergens that are able to induce the production of specific IgE antibodies in predisposed individuals. A lot of effort has been focused on obtaining the sequences and structures of these allergens due to the high health risk they represent. At present, 16 proteins present in peanuts are officially recognized as allergens. Research has also focused on their in-depth immunological characterization as well as on the design of modified hypoallergenic derivatives for potential use in clinical studies and the formulation of strategies for immunotherapy. Detailed research protocols are available for the purification of natural allergens as well as their recombinant production in bacterial, yeast, insect, and algal cells. Purified allergen molecules are now routinely used in diagnostic multiplex protein arrays for the detection of the presence of allergen-specific IgE. This review gives an overview on the wealth of knowledge that is available on individual peanut allergens.
Tree nut allergens
Tree nuts are considered as part of a healthy diet due to their high nutritional quality. However, they are also a potent source of allergenic proteins inducing IgE mediated hypersensitivity often causing serious, life-threatening reactions. The reported prevalence of tree nut allergy is up to 4.9% worldwide. The general term "tree nuts" comprises a number of nuts, seeds, and drupes, derived from trees from different botanical families. For hazelnut and walnut several allergens have been identified which are already partly applied in component resolved diagnosis, while for other tree nuts such as macadamia, coconut, and Brazil nut only individual allergens were identified and data on additional allergenic proteins are missing. This review summarizes the current knowledge on tree nut allergens and describes their physicochemical and immunological characterization and clinical relevance.
Tree Nut Allergies: Allergen Homology, Cross-reactivity, and Implications for Therapy.
Tree nut allergy is a potentially life-threatening disease that is increasing in prevalence, now affecting 1% of the general population in the United States. While other food allergies often resolve spontaneously, tree nut allergies are outgrown in less than 10% of cases. Due to the likelihood of cross-sensitization to multiple tree nut allergens, the current treatment guideline is strict avoidance of all nuts once one tree nut allergy has been diagnosed. For example, walnut and pecan are highly cross-reactive, along with cashew and pistachio, but the extent of clinical, IgE-mediated cross-reactivity among other tree nuts remains unclear, therefore making avoidance of all tree nuts a safe approach. There have been recent advances in immunotherapy for food allergies. For instance, there are investigational immunotherapies for milk, egg, and peanut allergies, specifically oral immunotherapy (OIT), sublingual immunotherapy (SLIT) and epicutaneous immunotherapy (EPIT). However, there are no large randomized controlled clinical trials for tree nut allergies. Even though there has been less research into tree nut allergy immunotherapies, the evidence of T cell cross-reactivity among tree nuts exists in animal models and in T cells from allergic patients indicates that immunotherapeutic interventions may be possible. Here, we review literature regarding epidemiology, allergen homology, and cross-reactivity among tree nuts, and explore how current findings can be employed for effective therapy.
Anacardic Acids from Cashew Nuts Prevent Behavioral Changes and Oxidative Stress Induced by Rotenone in a Rat Model of Parkinson’s Disease.
Anacardic acids (AAs) are alkyl phenols mainly presenting in cashew nuts. The antioxidant effects of these compounds have been an area of interest in recent research, with findings suggesting potential therapeutic use for certain diseases. Nevertheless, none of these studies were performed in order to test the hypothesis of whether anacardic acids are capable of preventing behavioral changes and oxidative stress induced by the pesticide rotenone in experimental model of Parkinson's disease. In our research, adult male rats were treated orally with AAs (1, 3, 10, 25, 50, or 100 mg/kg/day) 1 h before rotenone (3 mg/kg; s.c.) for five consecutive days. The behavioral testing strategies, including tests for general locomotor activity (open field), motor coordination (rotarod), and spatial memory performance (elevated T-maze), were carried out. Lipoperoxidation levels and total superoxide dismutase (t-SOD) activity, as well as cytoplasmic and mitochondrial SOD gene expression, were assessed in the substantia nigra (SN), striatum, and cerebral cortex. The results showed that AAs dose-dependently prevented the rotenone-induced learning and motor impairment from 10 mg/kg/day. AAs also precluded rotenone-induced lipoperoxidation in all doses, acting directly on the mitochondria, and improved the t-SOD activity in the doses 25-100 mg/kg/day. AAs per se (100 mg/kg/day) increased SOD gene expression and t-SOD activity. Our findings indicate that the oral administration of AAs prevents rotenone-induced behavioral changes and oxidative stress, in part due to a modulatory action on the mitochondria and SOD gene expression. These data suggest that AAs have promising neuroprotective action against degenerative changes in Parkinson's disease.
Nut consumption and incidence of seven cardiovascular diseases.
BACKGROUND: Nut consumption has been found to be inversely associated with cardiovascular disease mortality, but the association between nut consumption and incidence of specific cardiovascular diseases is unclear. We examined the association between nut consumption and incidence of seven cardiovascular diseases. METHODS: This prospective study included 61 364 Swedish adults who had completed a Food Frequency Questionnaire and were followed up for 17 years through linkage with the Swedish National Patient and Death Registers. RESULTS: Nut consumption was inversely associated with risk of myocardial infarction, heart failure, atrial fibrillation and abdominal aortic aneurysm in the age-adjusted and sex-adjusted analysis. However, adjustment for multiple risk factors attenuated these associations and only a linear, dose-response, association with atrial fibrillation (ptrend=0.004) and a non-linear association (pnon-linearity=0.003) with heart failure remained. Compared with no consumption of nuts, the multivariable HRs (95% CI) of atrial fibrillation across categories of nut consumption were 0.97 (0.93 to 1.02) for 1-3 times/month, 0.88 (0.79 to 0.99) for 1-2 times/week and 0.82 (0.68 to 0.99) for ≥3 times/week. For heart failure, the corresponding HRs (95% CI) were 0.87 (0.80 to 0.94), 0.80 (0.67 to 0.97) and 0.98 (0.76 to 1.27). Nut consumption was not associated with risk of aortic valve stenosis, ischaemic stroke or intracerebral haemorrhage. CONCLUSIONS: These findings suggest that nut consumption or factors associated with this nutritional behaviour may play a role in reducing the risk of atrial fibrillation and possibly heart failure.
Almonds and Cardiovascular Health: A Review.
Several preventive strategies to reduce dyslipidemia have been suggested, of which dietary modification features as an important one. Dyslipidemia is a major risk factor for coronary heart disease and strategies to manage dyslipidemia have been shown to reduce the incidence of cardiovascular disease (CVD). Although there are proven pharmacological therapies to help manage this condition, nutritional interventions are a safer option to help prevent and manage dyslipidemia. Addition of almonds in the daily diet has been proposed to beneficially impact the lipid profile. This review critically examines the available evidence assessing the effect of almonds on dyslipidemia in the South Asian (particularly Indian) context. An extensive review comprised of epidemiological studies, clinical trials, meta-analyses, and systematic reviews was conducted from published literature from across the world. Studies examining the effect of almonds on different aspects of dyslipidemia viz. high low-density lipoprotein-cholesterol (LDL-C), low high-density lipoprotein-cholesterol (HDL-C), triglyceridaemia, and high total cholesterol levels have been included. In several studies, almonds have been shown to reduce LDL-C-which is a known risk factor for CHD-and the effect of almonds has been well documented in systematic reviews and meta-analysis of clinical trials. Addition of almonds in the diet has been shown to not only to reduce LDL-C levels, but also to maintain HDL-C levels. This review provides information about the use of this simple nutritional strategy which may help manage known major risk factors for heart disease, such as high LDL-C and low HDL-C levels especially in the context of South Asians.