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Phytochemical info of Hazelnut or Corylus avellana L.
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Research Update:Hazelnut or Corylus avellana L.
Evaluation of the microelement profile of Turkish hazelnut (Corylus avellana L.) varieties for human nutrition and health.:Int J Food Sci Nutr. 2007 Jun 22;:1-12.Simsek A, Aykut O.Department of Food Engineering, Faculty of Agriculture, Ordu University, Ordu, Turkey.
In this study, the levels of boron (B), cobalt (Co), copper (Cu), chromium (Cr), iron (Fe), lithium (Li), nickel (Ni), selenium (Se) and zinc (Zn) microelements in 16 hazelnut samples were determined by inductively coupled plasma mass spectrometry and atomic absorption spectroscopy after microwave digestion, and are discussed for human nutrition and health. Significant differences were observed between the microelement contents of the 16 varieties (P<0.01). The average microelements concentrations in the varieties varied in the following ranges: B, 13.63-23.87; Co, 0.47-0.82; Cr, 0.22-0.52; Cu, 16.23-32.23; Fe, 31.60-51.60; Li, 0.035-0.042; Ni, 0.58-2.58; Se, 0.96-1.39; and Zn, 22.03-44.03 mg/kg. These results showed that hazelnuts can be an important microelement source for human nutrition and health. According to our trace element data, a daily consumption of 50 g hazelnut can supply easily about 6% for B, 9% for Co, 19% for Fe, 9% for Ni and 16% for Zn of the recommended daily allowance. On the other hand, Se, Cu and Cr levels of 50 g hazelnuts are higher than the respective daily requirements, but slight overdoses of these elements are non-toxic for human health.
Antioxidant phytochemicals in hazelnut kernel (Corylus avellana L.) and hazelnut byproducts.:J Agric Food Chem. 2007 Feb 21;55(4):1212-20. Epub 2007 Jan 24. Erratum in: J Agric Food Chem. 2007 Apr 18;55(8):3232.Shahidi F, Alasalvar C, Liyana-Pathirana CM.Department of Biochemistry, Memorial University of Newfoundland, St. John's, Newfoundland A1B 3X9, Canada. fshahidi@mun.ca
Antioxidant efficacies of ethanol extracts of defatted raw hazelnut kernel and hazelnut byproducts (skin, hard shell, green leafy cover, and tree leaf) were evaluated by monitoring total antioxidant activity (TAA) and free-radical scavenging activity tests [hydrogen peroxide, superoxide radical, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical], together with antioxidant activity in a beta-carotene-linoleate model system, inhibition of oxidation of human low-density lipoprotein (LDL) cholesterol, and inhibition of strand breaking of supercoiled deoxyribonucleic acid (DNA). In addition, yield, content of phenolics, and phenolic acid profiles (free and esterified fractions) were also examined. Generally, extracts of hazelnut byproducts (skin, hard shell, green leafy cover, and tree leaf) exhibited stronger activities than hazelnut kernel at all concentrations tested. Hazelnut extracts examined showed different antioxidative efficacies, expected to be related to the presence of phenolic compounds. Among samples, extracts of hazelnut skin, in general, showed superior antioxidative efficacy and higher phenolic content as compared to other extracts. Five phenolic acids (gallic acid, caffeic acid, p-coumaric acid, ferulic acid, and sinapic acid) were tentatively identified and quantified (both free and esterified forms). Extracts contained different levels of phenolic acids. These results suggest that hazelnut byproducts could potentially be considered as an excellent and readily available source of natural antioxidants.
Functional lipid characteristics of Turkish Tombul hazelnut (Corylus avellana L.).:J Agric Food Chem. 2006 Dec 27;54(26):10177-83.Alasalvar C, Amaral JS, Shahidi F.TUBITAK Marmara Research Center, Food Institute, P.O. Box 21, 41470 Gebze, Kocaeli, Turkey. Cesarettin.Alasalvar@mam.gov.tr
The quality of crude oil extracted from Tombul (Round) hazelnut, grown in the Giresun province of Turkey, was evaluated for its fatty acid, triacylglycerol (TAG), tocol, and phytosterol compositions. Oleic acid contributed 82.78% to the total fatty acids, followed by linoleic, palmitic, and stearic acids. Among 12 TAGs separated, 11 were identified (including one unknown): LLL, OLL, PLL, OOL, POL, PPL, OOO, POO, PPO, SOO, and PSO (where P, palmitoyl; S, stearoyl; O, oleoyl; and L, linoleoyl). The main components were OOO (71.31%), OOL (12.26%), and POO (9.45%), reflecting the high content of oleic acid present in hazelnut oil. Seven tocol isoforms (four tocopherols and three tocotrienols) and eight phytosterols as well as cholesterol were positively identified and quantified; among these, alpha-tocopherol (40.40 mg/100 g) and beta-sitosterol (134.05 mg/100 g) were predominant in hazelnut oil and contributed 78.74 and 81.28% to the total tocols and phytosterols present, respectively. Tocotrienols were detected in small amounts (1.02% to the total tocols). The crude hazelnut oil extracted from Turkish Tombul hazelnut, thus, serves as a good source of nutrients, bioactives, and health-promoting components.
Antioxidant and antiradical activities in extracts of hazelnut kernel (Corylus avellana L.) and hazelnut green leafy cover.:J Agric Food Chem. 2006 Jun 28;54(13):4826-32.Alasalvar C, Karama? M, Amarowicz R, Shahidi F.TUBITAK Marmara Research Center, Food Institute, P.O. Box 21, 41470 Gebze-Kocaeli, Turkey. calasalvar@mam.gov.tr
Phenolic compounds in the aqueous systems were extracted, from hazelnut kernel (HK) and hazelnut green leafy cover (HGLC), with 80% (v/v) ethanol (HKe and HGLCe) or 80% (v/v) acetone (HKa and HGLCa). The extracts were examined for their phenolic and condensed tannin contents and phenolic acid profiles (free and esterified fractions) as well as antioxidant and antiradical activities by total antioxidant activity (TAA), antioxidant activity in a beta-carotene-linoleate model system, scavenging of DPPH (2,2-diphenyl-1-picrylhydrazyl) radical, and reducing power. Significant differences (p < 0.05) in the contents of total phenolics, condensed tannins, and TAA existed among the extracts that were examined. HGLCa extract had the highest content of total phenolics (201 mg of catechin equivalents/g of extract), condensed tannins (542 mg of catechin equivalents/g of extract), and TAA (1.29 mmol of Trolox equivalents/g of extract) followed by HGLCe, HKa, and HKe extracts, respectively. Five phenolic acids (gallic acid, caffeic acid, p-coumaric acid, ferulic acid, and sinapic acid) were tentatively identified and quantified, among which gallic acid was the most abundant in both free and esterified forms. The order of antioxidant activity in a beta-carotene-linoleate model system, the scavenging effect on DPPH radical, and the reducing power in all extracts were in the following order: HGLCa > HGLCe > HKa > HKe. These results suggest that both 80% ethanol and acetone are capable of extracting phenolics, but 80% acetone was a more effective solvent for the extraction process. HGLC exhibited stronger antioxidant and antiradical activities than HK itself in both extracts and could potentially be considered as an inexpensive source of natural antioxidants.
HPLC screening of natural vitamin E from mediterranean plant biofactories--a basic tool for pilot-scale bioreactors production of alpha-tocopherol:J Plant Physiol. 2005 Nov;162(11):1280-3.Sivakumar G, Bacchetta L, Gatti R, Zappa G.BIOTEC-GEN, ENEA, Casaccia, Rome, Italy.
The study was performed in order to investigate a simple, efficient, reliable and rapid method of extracting and quantifying natural vitamin E for pressurized liquid extraction (PLE) as well as high-performance liquid chromatography (HPLC) analysis. Lyophilized Corylus avellana L. nut samples were powdered by high-speed milling with Waring blender for 40 s. alpha-Tocopherol was extracted from the nut tissue powder using dehydrated hexane fortified with 0.01% butylated hydroxytoluene (BHT, co-antioxidant). The rate of alpha-tocopherol accumulation showed differences among nut samples collected in different areas of Italy. Sarda Piccola nut biofactory contained higher amount (81.17 microg/g d.w) of alpha-tocopherol than other-local eleven Italian cultivar nuts. These results provide insight into the biofactory basis for alpha-tocopherol accumulation in hazelnut and give the suitable cultivar tissues to establish pilot-scale bioreactors production of natural bioactive vitamin E.
Phenolic profile of hazelnut (Corylus avellana L.) leaves cultivars grown in Portugal.:Nat Prod Res. 2005 Feb;19(2):157-63.Amaral JS, Ferreres F, Andrade PB, Valent?o P, Pinheiro C, Santos A, Seabra R.REQUIMTE, Servi?o de Farmacognosia, Faculdade de Farm¨¢cia, Universidade do Porto, R Anibal Cunha, 4050-047 Porto, Portugal.
In this study, phenolic compounds of hazelnut leaves of 10 different cultivars with the same cultural, geographical, geological and climatic conditions were analyzed by HPLC/DAD and HPLC/DAD/MS/MS - ESI. Eight phenolic compounds (3-caffeoylquinic acid, 5-caffeoylquinic acid, caffeoyltartaric acid, p-coumaroyltartaric acid, myricetin 3-rhamnoside, quercetin 3-glycoside, quercetin 3-rhamnoside and kaempferol 3-rhamnoside) were identified and quantified. All of the analyzed samples showed a similar phenolic profile, in which myricetin 3-rhamnoside and quercetin 3-rhamnoside were the major compounds and caffeoyltartaric and p-coumaroyltartaric acids were present in vestigial amounts.
Isolation and partial characterisation of acid phosphatase isozymes from dormant oilseed of Corylus avellana L.:Planta. 2004 Jun;219(2):346-58. Epub 2004 Mar 27.Andriotis VM, Ross JD.School of Plant Sciences, The University of Reading, Whiteknights, Reading, RG6 6AS, UK.
The acid phosphatase (orthophosphoric-monoester phosphohydrolase, EC 3.1.3.2) complement from dormant hazel (Corylus avellana L.) seeds was found to exhibit significant electrophoretic heterogeneity partially attributable to the presence of distinct molecular forms. In axiferous tissue, total acid phosphatase activity increased in a biphasic fashion during chilling, a treatment necessary to alleviate seed dormancy. Three acid phosphatase isozymes were isolated from cotyledons of dormant hazel seeds by successive ammonium sulphate precipitation, size-exclusion, Concanavalin A affinity, cation- and anion-exchange chromatographies resulting in 75-, 389- and 191-fold purification (APase1, APase2, APase3, respectively). The three glycosylated isoforms were isolated to catalytic homogeneity as determined by electrophoretic, kinetic and heat-inactivation studies. The native acid phosphatase complement of hazel seeds had an apparent Mr of 81.5 +/- 3.5 kDa as estimated by size-exclusion chromatography, while the determined pI values were 5.1 (APase1), 6.9 (APase2) and 7.3 (APase3). The optimum pH for p-nitrophenyl phosphate hydrolysis was pH 3 (APase1), pH 5.6 (APase2) and pH 6 (APase3). The hazel isozymes hydrolysed a variety of phosphorylated substrates in a non-specific manner, exhibiting low Km and the highest specificity constant (Vmax/ Km) for pyrophosphate. They were not primary phytases since they could not initiate phytic acid hydrolysis, while APase2 and APase3 had significant phospho-tyrosine phosphatase activity. Inorganic phosphate was a competitive inhibitor, while activity was significantly impaired in the presence of vanadate and fluoride.
Isolation and characterisation of phytase from dormant Corylus avellana seeds:Phytochemistry. 2003 Oct;64(3):689-99.Andriotis VM, Ross JD.School of Plant Sciences, The University of Reading, Whiteknights, Reading RG6 6AS, UK.
Phytase (myo-inositol-1,2,3,4,5,6-hexakisphosphate phosphohydrolase, EC 3.1.3.26), which catalyses the step-wise hydrolysis of phytic acid, was purified from cotyledons of dormant Corylus avellana L. seeds. The enzyme was separated from the major soluble acid phosphatase by successive (NH4)(2)SO(4) precipitation, gel filtration and cation exchange chromatography resulting in a 300-fold purification and yield of 7.5%. The native enzyme positively interacted with Concanavalin A suggesting that it is putatively glycosylated. After size exclusion chromatography and SDS-PAGE it was found to be a monomeric protein with molecular mass 72+/-2.5 kDa. The hazel enzyme exhibited optimum activity for phytic acid hydrolysis at pH 5 and, like other phytases, had broad substrate specificity. It exhibited the lowest Km (162 microM) and highest specificity constant (V(max)/Km) for phytic acid, indicating that this is the preferred in vivo substrate. It required no metal ion as a co-factor, while inorganic phosphate and fluoride competitively inhibited enzymic activity (Ki=407 microM and Ki=205 microM, respectively).
Comparison of natural and roasted Turkish tombul hazelnut (Corylus avellana L.) volatiles and flavor by DHA/GC/MS and descriptive sensory analysis:J Agric Food Chem. 2003 Aug 13;51(17):5067-72.Alasalvar C, Shahidi F, Cadwallader KR.Faculty of Health and Life Sciences, Food Research Center, University of Lincoln, Brayford Pool, Lincoln, LN6 7TS, United Kingdom. calasalvar@lincoln.ac.uk
Natural (raw) and roasted hazelnuts were compared for their differences in volatile components and sensory responses. A total of 79 compounds were detected in both hazelnuts, of which 39 (27 positive, 5 tentative, and 7 unknown) were detected in natural hazelnut and 71 (40 positive, 14 tentative, and 17 unknown) were detected in roasted hazelnut. These included ketones, aldehydes, pyrazines, alcohols, aromatic hydrocarbons, furans, pyrroles, terpenes, and acids. Pyrazines, pyrroles, terpenes, and acids were detected in roasted hazelnut only. Concentrations of several compounds increased as a result of roasting and these may play significant roles in the flavor of roasted hazelnut. Pyrazines together with ketones, aldehydes, furans, and pyrroles may contribute to the characteristic roasted aroma of hazelnut. Descriptive sensory analysis (DSA) showed that some flavor attributes such as "aftertaste", "burnt", "coffee/chocolate-like", "roasty", and "sweet" were rated significantly higher in roasted hazelnut compared to its natural counterpart. Natural and roasted hazelnuts can be distinguished using these attributes.
Turkish Tombul hazelnut (Corylus avellana L.). 2. Lipid characteristics and oxidative stability.:J Agric Food Chem. 2003 Jun 18;51(13):3797-805.Alasalvar C, Shahidi F, Ohshima T, Wanasundara U, Yurttas HC, Liyanapathirana CM, Rodrigues FB.Faculty of Health and Life Sciences, Food Research Center, University of Lincoln, Brayford Pool, United Kingdom. calasalvar@lincoln.ac.uk
The quality of crude hazelnut oil extracted from Tombul (Round) hazelnut, grown in the Giresun province of Turkey, was determined by measuring lipid classes, fatty acids, and fat soluble bioactives (tocopherols and phytosterols). Oxygen uptake, peroxide value, thiobarbituric acid reactive substances, and alpha-tocopherol levels of stripped and crude hazelnut oils in bulk and oil-in-water (o/w) emulsion systems were also evaluated as indices of lipid oxidation over a 21 day storage period at 60 degrees C in the dark. The total lipid content of Tombul hazelnut was 61.2%, of which 98.8% were nonpolar and 1.2% polar constituents. Triacylglycerols were the major nonpolar lipid class and contributed nearly 100% to the total amount. Phosphatidylcholine, phosphatidylethanolamine, and phosphatidylinositol were the most abundant polar lipids, respectively. Sixteen fatty acids were identified, among which oleic acid contributed 82.7% to the total, followed by linoleic, palmitic, and stearic acids. Unsaturated fatty acids accounted for 92.2% of the total fatty acids present. Among oil soluble bioactives, alpha-tocopherol (38.2 mg/100 g) and beta-sitosterol (105.5 mg/100 g) were predominant in hazelnut oil and comprised 88 and 93% of the total tocopherols and phytosterols present, respectively. The results also showed that both stripped and crude hazelnut oils were more stable in terms of lipid oxidation in the bulk oil as compared to those in an o/w emulsion.
Turkish Tombul hazelnut (Corylus avellana L.). 1. Compositional characteristics.:J Agric Food Chem. 2003 Jun 18;51(13):3790-6.Alasalvar C, Shahidi F, Liyanapathirana CM, Ohshima T.Faculty of Health and Life Sciences, Food Research Center, University of Lincoln, Brayford Pool, United Kingdom. calasalvar@lincoln.ac.uk
The quality of Tombul (Round) hazelnut, grown in the Giresun province of Turkey, was determined by measuring proximate composition, minerals, vitamins, dietary fiber, amino acids, and taste active components (free amino acids, sugars, and organic acids). Fat was the predominant component in Tombul hazelnut (approximately 61%). The major minerals were potassium, phosphorus, calcium, magnesium, and selenium. Hazelnut was also found to serve as an excellent source of vitamin E (24 mg/100 g) and a good source of water soluble (B complex) vitamins and dietary fiber. The major amino acids were glutamic acid, arginine, and aspartic acid. The three nonessential amino acids and the essential amino acids contributed 44.9 and 30.9% to the total amino acids present, respectively, while lysine and tryptophan were the limiting amino acids in Tombul hazelnut. Twenty-one free amino acids, six sugars, and six organic acids were positively identified; among these, arginine, sucrose, and malic acid predominated, respectively. These taste active components may play a significant role in the taste and flavor characteristics of hazelnut. Thus, the present results suggest that Tombul hazelnut serves as a good source of vital nutrients and taste active components.
Chemical composition of hazelnuts (Corylus avellana L.) grown in New Zealand.:Int J Food Sci Nutr. 1998 May;49(3):199-203. Savage GP, McNeil DL.Food Group, Lincoln University, Canterbury, New Zealand.
Hazelnut (Corylus avellana L.) samples were collected from all replications of six different cultivars of trees grown in an experimental orchard at Lincoln University. Five cultivars were originally imported from overseas, three from the USA and two from Europe, and one cultivar was selected locally. Representative samples of nuts were harvested from 12-year-old trees in autumn 1995. The total oil content of the hazelnuts ranged from 54.6 to 63.2% while the crude protein ranged from 14.3 to 18.2%. Dietary fibre ranged from 9.8 to 13.2% while the starch and free glucose content together made up no more than 5% of the remaining portion of the kernel. The amino acid content of the hazelnuts was similar between each cultivar and the pattern of essential amino acids was characteristic of a high quality protein.
Triacylglycerol and phospholipid composition of hazelnut (Corylus avellana L.) lipid fraction during fruit development.:J Agric Food Chem. 1999 Apr;47(4):1410-5.Parcerisa J, Codony R, Boatella J, Rafecas M.Department of Nutrition and Food Science, University of Barcelona, Spain. xparceri@farmacia.far.ub.es
We analyzed the triacylglycerol and phospholipid contents of hazelnuts from early development to maturity. Both were analyzed by high-performance liquid chromatography coupled to a light scattering detector. Trioleylglycerol, linoleyl-dioleylglycerol, and palmitoyl-dioleylglycerol were the most predominant triacylglycerols throughout development. Triacylglycerols showed small variation during hazelnut development. Phosphatidylcholine, phosphatidylethanolamine, and phosphatidylinositol were the most abundant phospholipids. Traces of phosphatidic acid were also detected. The statistical analysis showed that the positive correlation among the individual phospholipid contents was significant. Phospholipid contents showed a steep decrease during hazelnut development. Triacylgycerols and phosphatidylcholine were isolated by preparative thin-layer chromatography, and their fatty acid profile was determined by gas-liquid chromatography. Triacylglycerols showed a high percentage of monounsaturated fatty acid moieties, whereas phosphatidylcholine had the highest percentage of saturated and monounsaturated fatty acid moieties. The polyunsaturated fatty acid moiety showed low percentages in the triacylglycerol and phospholipid backbone.
Standardization of hazel leaf:Ann Pharm Fr. 1999 Sep;57(5):406-9. French.Fraisse D, Carnat A, Carnat AP, Lamaison JL.Laboratoire de Pharmacognosie et Phytoth¨¦rapie, Facult¨¦ de Pharmacie, Clermont-Ferrand.
Dried leaves of 9 harvested batches and 5 batches of commercial origin from Corylus avellana L. were examined. The levels of principal polyphenolic compounds averaged respectively: total flavonoids 2.58 and 2.58%, myricitrin 1.09 and 1.35%, quercitrin 0.30 and 0.40%, tannins 5.2 and 6.5%. Specifications were discussed for a French Pharmacopoeial monography.
Variations in leaf morphometry and nitrogen concentration in Betula pendula Roth., Corylus avellana L. and Lonicera xylosteum L:Tree Physiol. 1993 Apr;12(3):311-8.Kull O, Niinemets U.Institute of Ecology, Estonian Academy of Sciences, 40 Lai Str., EE 2400 Tartu, Estonia.
Relations between leaf dry weight to leaf area (LWA), leaf nitrogen concentration and irradiance inside a natural canopy were studied in Betula pendula Roth., Corylus avellana L. and Lonicera xylosteum L. In all species, LWA increased with increasing irradiance. Relative variability in LWA was smaller in Betula pendula than in the other two species. In Corylus avellana, LWA also depended on total plant height. Foliar nitrogen concentration (on a dry weight basis) increased with increasing irradiance and LWA in Betula pendula, but decreased in the other two species. The interspecific variation in response to light availability and in nitrogen partitioning may be caused by different light demands or different life forms (trees versus shrubs), or both, of the species examined, and must be considered in contemporary canopy models.
Analysis of 3-indolylacetic acid and abscisic acid by high-performance liquid chromatography and gas-liquid chromatography.:Anal Biochem. 1985 Apr;146(1):184-90.Rodriguez A, Sanchez Tames RS.
A method of analysis of 3-indolylacetic acid (IAA) and abscisic acid (ABA), allowing the simultaneous extraction of both regulators from plant material, has been developed. The method involves extraction with methanol, isolation of the acid fraction, diazomethane methylation, separation of the hormones through reverse-phase preparative high-performance liquid chromatography, and quantification of both compounds by gas-liquid chromatography. The recovery percentage at each step was monitored with radioactive compounds added at the beginning of the process. The final recovery was 70% for IAA and 96% for ABA. The method was applied to the analysis of the IAA and ABA content of stems of hazel (Corylus avellana L.).
The microscopical identification of fruits from Gevuina avellana Molina (author's transl):Z Lebensm Unters Forsch. 1978 Jun 28;166(5):304-6. German.Hohmann B.
The fruits of Gevuina avellana Molina, which in Chile are eaten like hazel-nuts, were subjected to microscopic examination. There are several anatomical characteristics, useful for differentiation. The anatomy of these nuts was then compared with that of hazel-nuts (Corylus avellana L.) is added.
Orderly arrangement of ribosomes in the embryogenic callus tissue of Corylus avellana L:J Cell Biol. 1976 Jun;69(3):686-92.Vujici? R, Radojevi? LJ, Neskovi? M.
Cultured callus tissue of hazel (Corylus avellana L.), which has the potency of somatic embryogenesis, was used for the study of cell ultrastructure in the course of callus growth and embryoid formation. The meristematic cells of this tissue exhibit a specific organization of rough endoplasmic reticulum (RER), stacked into extensive parallel sheets. The membranes of the aggregated RER are associated with orderly arrays of bound ribosomes. The high regularity of the alignment of the attached ribosomes seems to be influenced by the distance between the two neighbouring membranes in the RER aggregate. The RER aggregates with orderly attached ribosomes are more frequently found in callus cells and in early embryogenesis than in the advanced stages of embryo development.
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1.Research Update:Hazelnut or Corylus avellana L.
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