Allergenicity and structural properties of new Cor a 1 isoallergens from hazel identified in different plant tissues.

The hazel allergen Cor a 1 is a PR-10 protein, closely related to the major birch pollen allergen Bet v 1. Hazel allergies are caused by cross-reactive IgE antibodies originally directed against Bet v 1. Despite the importance of PR-10 proteins in allergy development, their function and localization in the plant remain largely elusive. Therefore, the presence of Cor a 1 mRNA and proteins was investigated in different tissues, i.e., the female flower, immature and mature nuts, catkins, and pollen. Four yet unknown Cor a 1 isoallergens, i.e., Cor a 1.0501-1.0801, and one new Cor a 1.03 variant were discovered and characterized. Depending on the isoallergen, the occurrence and level of mRNA expression varied in different tissues, suggesting different functions. Interestingly, Cor a 1.04 previously thought to be only present in nuts, was also detected in catkins and pollen. The corresponding Cor a 1 genes were expressed in Escherichia coli. The purified proteins were analysed by CD and NMR spectroscopy. Immunoblots and ELISAs to determine their allergenic potential showed that the new proteins reacted positively with sera from patients allergic to birch, hazel and elder pollen and were recognized as novel isoallergens/variants by the WHO/IUIS Allergen Nomenclature Sub-Committee.

Analysis of Polyphenol Extract from Hazel Leaf and Ameliorative Efficacy and Mechanism against Hyperuricemia Zebrafish Model via Network Pharmacology and Molecular Docking.

Hazel leaf, a by-product of hazelnuts, is commonly used in traditional folk medicine in Portugal, Sweden, Iran and other regions for properties such as vascular protection, anti-bleeding, anti-edema, anti-infection, and pain relief. Based on our previous studies, the polyphenol extract from hazel leaf was identified and quantified via HPLC fingerprint. The contents of nine compounds including kaempferol, chlorogenic acid, myricetin, caffeic acid, p-coumaric acid, resveratrol, luteolin, gallic acid and ellagic acid in hazel leaf polyphenol extract (ZP) were preliminary calculated, among which kaempferol was the highest with 221.99 mg/g, followed by chlorogenic acid with 8.23 mg/g. The inhibition of ZP on α-glucosidase and xanthine oxidase activities was determined via the chemical method, and the inhibition on xanthine oxidase was better. Then, the effect of ZP on hyperuricemia zebrafish was investigated. It was found that ZP obviously reduced the levels of uric acid, xanthine oxidase, urea nitrogen and creatinine, and up-regulated the expression ofOAT1 and HPRT genes in hyperuricemia zebrafish. Finally, the targeted network pharmacological analysis and molecular docking of nine polyphenol compounds were performed to search for relevant mechanisms for alleviating hyperuricemia. These results will provide a valuable basis for the development and application of hazel leaf polyphenols as functional ingredients.

Green synthesized Ag nanoparticles stimulate gene expression and paclitaxel production in Corylus avellana cells.

Synthesis of nanoparticles (NPs) through plant extracts has been suggested as an effective and nature-friendly method. Paclitaxel is one of the most valuable secondary metabolites with therapeutic uses, and hazelnut has been suggested as one of the sustainable resources for producing this metabolite. In the present study, we synthesized Ag NPs using the ethanolic extract of C. avellana leaves and were characterized using UV-visible, FTIR, XRD, EDX, DLS, SEM, and TEM analyses. In addition, we investigated the effect of green synthesized Ag (GS Ag) NPs (5 and 10 mg/L), para-aminobenzoic acid (PABA) (20 mg/L), and AgNO3 (10 mg/L) on cell viability, physiological characteristics, gene expression, and biosynthesis of secondary metabolites in hazelnut cell cultures. The results showed that 10 mg/L Ag NPs and AgNO3 significantly affected the cell viability, the content of ROS, peroxidation of lipids, antioxidant capacity, secondary metabolite production, and expression pattern of the genes involved in the taxanes biosynthesis pathway in the hazelnut cells. The cytotoxicity increased by increasing the GS Ag NPs concentration from 5 to 10 mg/L, which was associated with reduced membrane integrity and cell viability. Elicitation of the cells with 10 mg/L Ag NPs combined with 20 mg/L PABA (as a precursor) remarkably excited the expression of TAT and GGPPS genes and the production of secondary metabolites as well as paclitaxel. So that the highest expression of TAT and GGPPS genes (3.71 and 3.69) and the highest amount of taxol (230.21 µg g-1 FW) and baccatin (1025.8 µg g-1 FW) were observed in this treatment. KEY POINTS: • For the first time, we assessed and reported the molecular and physiological responses of C. avellana cells to GS Ag NPs, AgNO3, and PABA. • In hazel cells, GS Ag NPs stimulate several physiological and molecular responses. • In addition to increasing antioxidant activity, GS Ag NPs significantly increased the expression of genes involved in the paclitaxel biosynthesis pathway and the production of secondary metabolites.

Hazelnut (Corylus avellana L.) shells as a potential source of dietary fibre: impact of hydrothermal treatment temperature on fibre structure and degradation compounds.

BACKGROUND: Hemicellulose extraction from lignocellulosic biomasses has gained interest over the years, and hydrothermal treatment is one of the most common methods employed for this purpose. This work aimed to deeply study hazelnut (Corylus avellana L.) shells as a new source of dietary fibre, evaluating the effect of hydrothermal treatment temperatures on the type and structure of fibre extracted, but also on the formation of side-products derived from lignocellulose degradation. RESULTS: Different process temperatures led to diverse polysaccharides in the hydrothermal extract. Pectin was identified for the first time in hazelnut shells when experimenting with extraction at 125 °C, whereas at 150 °C a heterogeneous mixture of pectin, xylan, and xylo-oligosaccharides was present. The highest yield in terms of total fibre was gained at 150 and 175 °C, and then decreased again at 200 °C. Finally, more than 500 compounds from different chemical classes were putatively identified and they appeared to be present in the extracted fibre with a different distribution and relative amount, depending on the heat treatment severity. A generally high content of phenols, phenyls, oligosaccharides, dehydro-sugars, and furans was observed. CONCLUSIONS: Modulation of the hydrothermal treatment temperature allows fibre extracts with very different compositions, and therefore different potential end uses, to be obtained from hazelnut shells. A sequential temperature-based fractionation approach, as a function of the severity of the extraction parameters, can also be considered. Nevertheless, the study of the side-compounds formed from lignocellulosic matrix degradation, as a function of the applied temperature, needs to be fully addressed for a safe introduction of the fibre extract within the food chain. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Detection of Hazelnut and Almond Adulteration in Olive Oil: An Approach by qPCR.

Virgin olive oil (VOO), characterized by its unique aroma, flavor, and health benefits, is subject to adulteration with the addition of oils obtained from other edible species. The consumption of adulterated olive oil with nut species, such as hazelnut or almond, leads to health and safety issues for consumers, due to their high allergenic potential. To detect almond and hazelnut in olive oil, several amplification systems have been analyzed by qPCR assay with a SYBR Green post-PCR melting curve analysis. The systems selected were Cora1F2/R2 and Madl, targeting the genes coding the allergenic protein Cor a 1 (hazelnut) and Pru av 1 (almond), respectively. These primers revealed adequate specificity for each of the targeted species. In addition, the result obtained demonstrated that this methodology can be used to detect olive oil adulteration with up to 5% of hazelnut or almond oil by a single qPCR assay, and with a level as low as 2.5% by a nested-qPCR assay. Thus, the present research has shown that the SYBR-based qPCR assay can be a rapid, precise, and accurate method to detect adulteration in olive oil.

Hemp seed: An allergen source with potential cross-reactivity to hazelnut.

The increasing exposure of the population to Cannabis sativa has revealed allergies to different parts of the plant, among which hemp seed. Nonetheless, the major hemp seed allergens remain to be identified. Several known families of allergens are present in hemp seed, including notably seed storage proteins. We therefore aimed to investigate the potential allergenicity of the hemp seed storage proteins and their potential cross-reactivity to different seeds and nuts. For this, we extracted hemp seed proteins sequentially using buffers with increasing levels of salinity (H2O, T2 and T3) to yield extracts differentially enriched in storage proteins. We used these extracts to perform immunoblots and ELISAs using sera of patients either sensitized to hemp seeds or sensitized/allergic to other seeds and nuts. Immunoblots and proteomics analyses identified vicilins and edestins as potential hemp seed allergens. Moreover, ELISA analyses revealed a correlation between sensitization to hazelnut and the hemp seed T3 extract (enriched in storage proteins). The possible cross-reactivity between hazelnut and hemp seed proteins was further strengthened by the results from inhibition ELISAs: the incubation of sera from hazelnut-sensitized individuals with increasing concentrations of the T3 extract inhibited serum IgE binding to the hazelnut extract by about 25-30%. Our study thus identifies vicilins and edestins as potential hemp seed allergens and highlights a possible cross-reactivity with hazelnut. The clinical relevance of this cross-reactivity between hemp seed and hazelnut needs to be further investigated in hazelnut-allergic individuals.

Characterization of phenolic constituents in hazelnut kernels.

Hazelnuts contain biologically active phenolic compounds and are widely used for their nutritional value. In this study, the phenolic compounds contained in hazelnuts were isolated from the kernels of Corylus avellana L. and investigated. Spectral analyses revealed 2 new acetophenone glycosides, characterized as 2',4',6'-trihydroxyacetophenone-4'-O-(2-O-ß-d-apiosyl)-ß-d-glucoside and 2',4',6'-trihydroxyacetophenone-4'-O-(2-O-ß-d-apiosyl-6-O-α-l-arabinosyl)-ß-d-glucoside, and 4 known compounds. Four high-molecular-mass condensed tannin fractions were detected in the water-soluble fraction of the extract, characterized as B-type procyanidin consisting of extension and terminal units. Gel permeation chromatography analyses revealed that the average molecular mass, based on the polystyrene standard, was approximately 15 000-113 000. These high-molecular-mass condensed tannin fractions were chemically characterized and exhibited different molecular weights. The fractions of high-molecular-mass condensed tannins were obtained from hazelnuts and tested for 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity. The EC50 values indicated significant activity for all the fractions.

Characterization of selected dietary fibers microparticles and application of the optimized formulation as a fat replacer in hazelnut spreads.

The present work demonstrates the application of the spray drying technique to produce microparticulates of different dietary fibers with particle sizes<10 µm. It examines their role as potential fat replacers for hazelnut spread creams. Optimization of a dietary fiber formulation containing inulin, glucomannan, psyllium husk, and chia mucilage to obtain high viscosity, water holding capacity, and oil holding capacity was conducted. Microparticles containing 46.1, 46.2, and 7.6 weight percentages of chia seed mucilage, konjac glucomannan, and psyllium husk showed a spraying yield of 83.45 %, a solubility of 84.63 %, and viscosity of 40.49 Pas. When applied to hazelnut spread creams, microparticles substituted palm oil by 100 %; they produced a product with a total unsaturated and saturated fat reduction of 41 and 77 %, respectively. An increase in dietary fibers of 4 % and a decrease in total calories of 80 % were also induced when compared with the original formulation. Hazelnut spread with dietary fiber microparticles were preferred by 73.13 % of the panelist in the sensory study due to an enhancement in brightness. The demonstrated technique could be used to increase the fiber content while decreasing the fat content in some commercial products, such as peanut butter or chocolate cream.

The potential of almonds, hazelnuts, and walnuts SFE-CO2 extracts as sources of bread flavouring ingredients.

Nuts have been part of the human diet since our early ancestors, and their use goes beyond nutritional purposes, for example, as aromatic sources for dairy products. This work explores the potential of almond (Prunus dulcis (Mill.) DA Webb), hazelnut (Corylus avellana L.), and walnut (Juglans regia L.) extracts as sources of food flavouring agents, suggesting a new added-value application for lower quality or excess production fruits. The extracts were obtained by supercritical fluid extraction with carbon dioxide and characterized by: quantification of the volatile fraction by HS-SPME GC-MS; sensory perception and description; and cytotoxicity against Vero cells. All extracts revealed potential as flavouring ingredients due to terpene abundance. No significant differences were observed for the minimal sensory perception, in which the odour threshold values ranged from 8.3 × 10-4 to 6.9 × 10-3 µg·mL-1 for walnuts and almonds extracts, respectively. In contrast, the cytotoxic potential differed significantly among the extracts, and P. dulcis extract presented lower cytotoxicity. Notes as woody, fresh, and green were identified in the volatile intensifiers obtained from the P. dulcis extract. Thus, almond extract was identified as the most promising ingredient to increase the sensory value of food products, namely bread. This potential was verified by an increase in the odour perception of bread after adding 4 µL of extract to each 100 g of bread dough. The quantified eucalyptol and d-limonene terpenes - found in the P. dulcis extract - have improved the release of the pleasant and natural volatile compounds from bread crust and crumb compared to the control bread chemical and sensory profiles.

Epigenetic-based antioxidant effect of an ethanolic extract of Corylus avellana L. on THLE-2 human primary hepatocytes.

The ethanolic extract of Corylus avellana L hazelnut, prepared in our laboratories, has been previously characterized by liquid chromatography coupled to high resolution mass spectrometry. We here aimed at testing the antioxidant effect of such extract in H2O2-challenged THLE-2 human primary hepatocytes and verified whether it might be based on microRNA-34b/c expression changes. We here demonstrate that miR-34b/miR-34c undergo significant stimulation (≥2-fold change, p < 0.05) in THLE-2 when treated for 72h with not-toxic hazelnut concentrations (0.04-0.4 mg/ml), when compared with 0.06% ethanol control. When administered with H2O2 (1000-2000 µM, 24h), THLE-2 are significantly protected from oxidative stress if pre-treated with hazelnut, the H2O2-driven cytotoxicity and reactive oxygen species generation being recovered by hazelnut extract, through miR-34b/c stimulation. Although preliminary, our findings pave the way for further preclinical studies aimed at validating the possible health-related application of hazelnut matrix, and/or its metabolites, as powerful epigenetic-based drugs, food supplements or nutraceuticals.

Effect of hazelnut skin by-product supplementation in lambs' diets: Implications on plasma and muscle proteomes and first insights on the underlying mechanisms.

This study aimed to evaluate the effect of hazelnut skin by-product supplementation on lamb meat quality characteristics and plasma and muscle proteomes. Twenty-two Valle del Belice male lambs were divided into two experimental groups: control (C), fed a maize-barley diet and hazelnut (H), fed hazelnut skin by-product as maize partial replacer in the concentrate diet. The meat of lambs fed hazelnut skin showed greater values of lightness, redness, yellowness, and chroma color parameters together with the highest myofibril fragmentation index. Two-dimensional electrophoresis and mass spectrometry applied on plasma proteome identified 20 protein spots corresponding to 18 unique gene names to be differently expressed due to hazelnut skin by-product substitution. For the early post-mortem muscle, 23 protein spots (42 unique gene names) were significantly up-regulated due to hazelnut skin by-product supplementation. Four proteins these being APOA1, PHB, ACTG1 and ALB, were found to be common to the two proteomes suggesting that these proteins could be candidate biomarkers to monitor in vita and post-mortem lamb meat quality traits. This study evidenced the main mechanisms involved in the supplementation of hazelnut skin by-product in lambs' diet and confirmed the possibility of using plasma proteome as a non-invasive way to predict lamb meat quality. SIGNIFICANCE: Maximizing the use of agro-industrial by-products as replacers of traditional feedstuff for improving animal products is one of the important challenges to preserving natural resources and guaranteeing environmental sustainability. Hazelnut (Corylus avellana L.) skin, obtained as a results of hazelnut roasting, represents a valuable by-products due to its high content in unsaturated fatty acids, tannins, and vitamins. Thus, including hazelnut skin by-product in small ruminant nutrition could reduce the costs of animal feedings for farmers as well as improve meat nutritional and sensorial characteristics. Additionally, monitoring the meat quality characteristics with fast, accurate, and non-invasive tools to find, before slaughter, animals with desired quality characteristics is of growing interest in the last years. In this regard, the objectives of this study were to assess i) the effect of hazelnut skin supplementation on lamb meat quality characteristics and plasma and muscle proteomes, and ii) whether analyzing plasma proteome by using a gel-based proteomic approach could effectively offer a more readily available option for determining lamb meat quality. Taken together, the proteomic approach applied to plasma and muscle proteomes, allowed us to reveal the pathways and the potential candidate plasma biomarkers to predict lamb meat production in the pre-slaughter phase.

Biologically synthesized CuO nanoparticles induce physiological, metabolic, and molecular changes in the hazel cell cultures.

The utilization of plant extracts in nanoparticle (NP) synthesis has been suggested as a nature-friendly method and an efficient alternative to the conventional approaches such as physical and chemical methods. Taxol is a valuable medicinal compound, and hazelnut has been suggested as one of the sustainable resources for producing this metabolite. In the present research, copper oxide (CuO) nanoparticles (NPs) were biologically synthesized by utilizing hazelnut leaf extracts. FTIR, XRD, EDAX, DLS, and SEM analyses were used for characterizing and confirming the synthesized NPs. The effect of biosynthesized CuO NPs (10 and 90 ppm), para-aminobenzoic acid (PABA) (20 ppm), and CuSO4 (10 ppm) on the cell viability, biochemical properties, expression of TAT and GGPPS genes, and accumulation of taxol and baccatin III in hazelnut cell cultures was investigated. The results indicated that biosynthesized CuO NPs significantly influenced the cell viability, amount of ROS, antioxidant capacity, lipid peroxidation, secondary metabolite production, and expression pattern of the genes engaged in the biosynthesis pathway of taxanes in the C. avellana L. cells. The cytotoxicity of CuO NPs to cells was dose dependent and increased with increasing its concentration, as evidenced by a decline in the survival rate and cell membrane integrity. Furthermore, the utilization of 10 ppm CuSO4 caused more toxicity in the cells than the same concentration of CuO NPs. This result could be attributed to the fact that plant extracts components act as a coating for the NPs and reduce their toxicity. Treatment of the cell cultures with CuO (10 ppm) + PABA (20 ppm) and CuO (10 ppm) induced the highest radical scavenging activity. The activity of antioxidant enzymes was increased with increasing the copper oxide NPs level from 10 to 90 ppm. Contrariwise, the cell's survival rate, radical scavenging activity, and amount of secondary metabolites were significantly reduced in the higher levels of copper oxide NPs (90 ppm) compared to the 10 ppm. The combined utilization of 10 ppm copper oxide NPs and 20 ppm PABA considerably stimulated the TAT and GGPPS genes expression and produced the highest amount of taxol and baccatin III. KEY POINTS: • CuO NPs were biologically synthesized using the hazel leaf extracts and confirmed by FTIR, XRD, EDAX, DLS, and SEM analyses. • CuO NPs significantly affected the amount of ROS, antioxidant capacity, and lipid peroxidation in C. avellana L. cells. • Treatment of the hazel cells with CuO NPs increased the production of secondary metabolites including taxol and baccatin III and expression of the genes involved in taxol and baccatin III biosynthesis (TAT and GGPPS).

Microwave-assisted extraction of antioxidant compounds from by-products of Turkish hazelnut (Corylus avellana L.) using natural deep eutectic solvents: Modeling, optimization and phenolic characterization.

An environmentally friendly method using natural deep eutectic solvents (NADES) and microwave-assisted extraction (MAE) for the recovery of bioactive compounds from hazelnut pomace (a hazelnut oil process by-product) was developed to contribute to their sustainable valorization. Eight different NADES were prepared for the extraction of antioxidant constituents from hazelnut pomace, and choline chloride:1,2-propylene glycol (CC-PG) was determined as the most suitable NADES, considering their extraction efficiency and physicochemical properties. After selecting suitable NADES, operational parameters for the MAE process of antioxidants from hazelnut pomace were optimized and modeled using response surface methodology. For the highest recovery of antioxidants, the operational parameters of the MAE process were found to be 24% water, 38 min, 92 °C and 18 mL/0.1 g-DS. Under optimized conditions, extracts of both pomace as a by-product and unprocessed hazelnut flours of three different hazelnut samples (Tombul, Çakildak, and Palaz) were prepared, and their antioxidant capacities were evaluated by spectrophotometric methods. Antioxidant capacities of CC-PG extracts of all hazelnut samples were 2-3 times higher than those of ethanolic extracts. In addition, phenolic characterization of the prepared extracts was carried out using the UPLC-PDA-ESI-MS/MS system. The results of this study suggest that hazelnut by-products can potentially be considered an important and readily available source of natural antioxidants. Furthermore, the modeled MAE procedure has the potential to create an effective and sustainable alternative for pharmaceutical and food industries.

Molecular cloning and yeast two-hybrid provide new evidence for unique sporophytic self-incompatibility system of Corylus.

The Corylus genus contains several important nut producing species and exhibits sporophytic self-incompatibility (SSI). However, the underlying molecular mechanisms of SSI in Corylus remain largely unknown. To clarify whether Corylus and Brassica share the same SSI molecular mechanism. We cloned ChaTHL1/2, ChaMLPK, ChaARC1, ChaEX70A1 genes from Ping'ou hybrid hazelnut using RACE techniques and tested the interaction between the ChaARC1 and ChaSRK1/2. We also examined the pistil-pollen interactions using scanning electron microscopy. We found no differences in the stigma surface within 1 h after compatible or incompatible pollination. Compatible pollen tubes penetrated the stigma surface, while incompatible pollen did not penetrate the stigma 4 h after pollination. Bioinformatics analysis revealed that ChaTHL1/2, ChaMLPK, ChaARC1 and ChaEX70A1 have corresponding functional domains. Quantitative real-time PCR (qRT-PCR) analysis showed that ChaTHL1/2, ChaMLPK, ChaARC1 and ChaEX70A1 were not regularly expressed in compatible or incompatible pollination. Furthermore, the expression patterns of ARC1, THL1/2, MLPK and Exo70A1 were quite distinct between Corylus and Brassica. According to yeast two-hybrid assays, ChaSRK1/2 did not interact with ChaARC1, confirming that the SRK-ARC1 signalling pathway implicated in the SSI response of Brassica was not conserved in Corylus. These results further reinforce the conclusion that, notwithstanding the similarity of the genetic basis, the SSI mechanism of Corylus does not conform in many respects with that of Brassica. Our findings could be helpful to better explore the potential mechanism of SSI system in Corylus.

Monitoring of Hazelnut oil quality during thermal processing in comparison with extra virgin olive oil by using ATR-FTIR spectroscopy combined with chemometrics.

Hazelnut oil (HO), which is not widely used because its healthy properties are not fully known yet, is an excellent nutrient due to its high content of monounsaturated fatty acids and antioxidants. In this study, the effects of thermal processing on the quality of HO in comparison to extra virgin olive oil (EVOO), which is one of the healthiest and heat-resistant oils, were investigated using Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) spectroscopy. Oil samples were heated at a frying temperature (180 °C) for 24 h in periods of 8 h per day and alterations in the spectra of these oils sampled every 2 h were evaluated. The heating process caused decreases in the areas of the bands at 3007 and 722 cm-1 and the area ratios of 3007/2854 and 722/2854 cm-1 and increases in the areas of the bands at 987 and 965 cm-1 and the area ratio of 965/2854 cm-1 in both oils suggesting the conjugation and cis-trans isomerization of unsaturated fatty acids. In addition, heating caused increases in the areas of the bands at 3475 and 1744 cm-1 and the ratios of 3475/2854 cm-1 and 1744/2854 cm-1, a shift to a lower value in the wavenumber and a broadening of the 1744 cm-1 band indicating the formation of primary and secondary oxidation products in the heated oils, which were also supported by chemical studies. Most of these changes began earlier in EVOO and all occurred to a higher extent, revealing that HO has a higher thermal stability than EVOO. Principal component analysis and hierarchical cluster analysis confirmed that HO is more resistant to heat than EVOO. These results showed that HO is superior to EVOO and it could be used for frying as a healthier and cheaper oil alternative. This study also indicated that oil oxidation could be monitored easily and rapidly via ATR-FTIR spectroscopy.

Measurement of IgE to hazelnut allergen components cannot replace hazelnut challenge in Dutch adults.

BACKGROUND: Component-resolved diagnostics (CRD) help predict hazelnut allergy (HA) in children, but are of unknown diagnostic value in adults. This study aimed to evaluate the diagnostic accuracy of IgE to hazelnut extract and components in adults. METHODS: A Dutch population of consecutively presenting adults suspected of HA, who underwent a double-blind placebo-controlled food challenge, were included. Serum IgE to hazelnut extract and Cor a 1, 8, 9, and 14 was measured on ImmunoCAP. Diagnostic accuracy was assessed by area under the curve (AUC) analysis. RESULTS: Of 89 patients undergoing challenge, 46 had challenge-confirmed HA: 17 based on objective and 29 based on subjective symptoms. At commonly applied cutoffs 0.1 and 0.35 kUA /L, high sensitivity was observed for IgE to hazelnut extract and Cor a 1 (range 85-91%), and high specificity for IgE to Cor a 8, 9 and 14 (range 77-95%). However, the AUCs for hazelnut extract and components were too low for accurate prediction of HA (range 0.50-0.56). Combining hazelnut extract and component IgE measurements did not significantly improve accuracy. Higher IgE levels to Cor a 9 and 14 were tentatively associated with HA with objective symptoms, but the corresponding AUCs still only reached 0.68 and 0.63, respectively. CONCLUSIONS: Although hazelnut allergic adults are generally sensitized to hazelnut extract and Cor a 1, and hazelnut tolerant adults are usually not sensitized to Cor a 8, 9, or 14, challenge testing is still needed to accurately discriminate between presence and absence of HA in adults from a birch-endemic country.

Hazelnut Shells as Source of Active Ingredients: Extracts Preparation and Characterization.

Hazelnut shells represent a waste material (about 42% of the total biomass) deriving from hazelnut harvest. These are mainly used as a heating source; however, they represent an interesting source of polyphenols useful in health field. The impact on phenolic profile and concentrations of hazelnut shell extracts obtained by three extraction methods (maceration, ultrasonic bath, and high-power ultrasonic), as well as temperature, extraction time, and preventive maceration, was studied. The prepared extracts were characterized in terms of chemical composition, antioxidant and antimicrobial activities. Eighteen different phenolic compounds were identified and quantified by chemical analysis and gallic acid was the most abundant in all the extracts analyzed. Other relevant compounds were chlorogenic acid, protocatechuic acid and catechin. Preventive maceration had a positive effect on the extraction of different types of compounds regardless of the method performed. Application of the high-power ultrasonic method had different effects, either positive or negative, depending on the type of compound and extraction time. All the prepared extracts showed antioxidant activity especially those prepared by maceration, and many of them were able to inhibit the growth of both B. subtilis and B. cereus.

Effects of hazelnut supplemented diet on doxorubicin-induced damage of reproductive system in male rats.

The present study was objected to investigate the effect of hazelnut supplemented diet on the levels of oxidative stress and fertility parameters against doxorubicin-induced testicular and epididymal tissue damage of male rats. Rats were randomly divided into four groups (each n = 8), namely control group (CG), doxorubicin group (DG), doxorubicin + hazelnut group (DHG), and doxorubicin + vitamin E group (DEG). This is the first study designed using DHG. Doxorubicin was intraperitoneally injected into all diet groups except CG at a dose of 3 mg/kg body weight on days 1, 7, 14, 21, and 28. In addition, DHG was supplemented with a hazelnut diet at a dose of 3 g/kg body weight/day and vitamin E was added to the drinking water of DEG at a dose of 50 mg/kg body weight/day. DHG reversed the side effects of doxorubicin and positively improved the epididymis sperm quality, testicular and epididymal tissue injury, testosterone level, epididymis oxidative stress index, and lipid peroxidation in male rats. These findings suggest that hazelnut has positive effects against doxorubicin dependent damage on male rats and it may be a promising supplement for amelioration of testicular toxicity. PRACTICAL APPLICATIONS: Hazelnut has numerous positive health effects due to its macronutrients, micronutrients, lipid-soluble compounds and bioactive phenolics. Studies have shown that regular consumption of hazelnut may have a positive effect on lipid parameters, oxidative stress, inflammation markers, and endothelial dysfunction in both healthy people and patients with chronic diseases. Although doxorubicin (Adriamycin, DOX) is an antibiotic that has been widely used in cancer treatment for nearly 30 years, it causes organ toxicity including testicular tissue. Hazelnut may have positive effects on the damage caused by DOX in the reproductive system. However, studies on the effect of hazelnut on male reproductive health are scarce. Therefore, this study provided a basis for the clinical evaluation of the effects of hazelnut on the reproductive system.

Identification and in-silico characterization of taxadien-5α-ol-O-acetyltransferase (TDAT) gene in Corylus avellana L.

Paclitaxel® (PC) is one of the most effective and profitable anti-cancer drugs. The most promising sources of this compound are natural materials such as tissue cultures of Taxus species and, more recently, hazelnut (Corylus avellana L.). A large part of the PC biosynthetic pathway in the yew tree and a few steps in the hazelnut have been identified. Since understanding the biosynthetic pathway of plant-based medicinal metabolites is an effective step toward their development and engineering, this paper aimed to identify taxadiene-5α-ol-O-acetyltransferase (TDAT) in hazelnut. TDAT is one of the key genes involved in the third step of the PC biosynthetic pathway. In this study, the TDAT gene was isolated using the nested-PCR method and then characterized. The cotyledon-derived cell mass induced with 150 µM of methyl jasmonate (MeJA) was utilized to isolate RNA and synthesize the first-strand cDNA. The full-length cDNA of TDAT is 1423 bp long and contains a 1302 bp ORF encoding 433 amino acids. The phylogenetic analysis of this gene revealed high homology with its ortholog genes in Quercus suber and Juglans regia. Bioinformatics analyses were used to predict the secondary and tertiary structures of the protein. Due to the lack of signal peptide, protein structure prediction suggested that this protein may operate at the cytoplasm. The homologous superfamily of the T5AT protein, encoded by TDAT, has two domains. The highest and lowest hydrophobicity of amino acids were found in proline 142 and lysine 56, respectively. T5AT protein fragment had 24 hydrophobic regions. The tertiary structure of this protein was designed using Modeler software (V.9.20), and its structure was verified based on the results of the Verify3D (89.46%) and ERRAT (90.3061) programs. The T5AT enzyme belongs to the superfamily of the transferase, and the amino acids histidine 164, cysteine 165, leucine 166, histidine 167, and Aspartic acid 168 resided at its active site. More characteristics of TDAT, which would aid PC engineering programs and maximize its production in hazelnut, were discussed.

Production of Haploid and Doubled Haploid Lines in Nut Crops: Persian Walnut, Almond, and Hazelnut.

This chapter deals with induction of haploidy via parthenogenesis in Persian walnut and via microspore embryogenesis in almond and hazelnut. Haploid induction through in situ parthenogenesis using pollination with irradiated pollen to stimulate the embryogenic development of the egg cell, followed by in vitro culture of the immature haploid embryos. Microspore embryogenesis allows the induction of immature pollen grains (microspores), to move away from the normal gametophytic developmental route in the direction of the sporophytic one, yielding homozygous organisms (embryos in this case). Unlike other fruit crops (such as Citrus), regeneration of entire plants has not yet been obtained in our studied nut crops; however, it gives the methodology should be used to continue the roadmap.