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socio-ecological costs of amazon nut and timber production at community household forests in the bolivian amazon.the bolivian amazon holds a complex configuration of people and forested landscapes in which communities hold secure tenure rights over a rich ecosystem offering a range of livelihood income opportunities. a large share of this income is derived from amazon nut (bertholletia excelsa). many communities also have long-standing experience with community timber management plans. however, livelihood needs and desires for better living conditions may continue to place these resources under considerabl ...201728235090
occurrence and fumonisin b2 producing potential of aspergillus section nigri in brazil nuts.bertholletia excelsa is the tree that produces brazil nuts which have vast economic importance in the amazon region and as an export commodity. the aim of this study was to assess the presence of aspergillus section nigri in brazil nut samples at different stages of its production chain and to verify the toxigenic potential for fumonisin b2 (fb2) production of these isolates along with the presence of this mycotoxin in brazil nut samples. the fungal infection ranged from 0 to 80% at the differen ...201727817100
physicochemical characterization, fatty acid composition, and thermal analysis of bertholletia excelsa hbk oil.the present study aimed at characterizing the oil extracted from bertholletia excelsa h.b.k. almond, a native species from the amazon region. analytical methods used for oils and fats were employed through pharmacopoeia assays, aocs (american oil chemists society) standard methods as well as those recommended by anvisa (national health surveillance agency) such as acidity, peroxide value, saponification index, iodine value and refractive index, ph and relative density, and also thermoanalytical ...201725709225
pro198leu polymorphism affects the selenium status and gpx activity in response to brazil nut intake.selenoproteins play important roles in antioxidant mechanisms, and are thus hypothesised to have some involvement in the pathology of certain types of dementia. mild cognitive impairment (mci) and alzheimer's disease (ad) are both thought to involve impaired biological activity of certain selenoproteins. previously, supplementation with a selenium-rich brazil nut (bertholletia excelsa) has shown potential in reducing cognitive decline in mci patients, and could prove to be a safe and effective n ...201626661784
high hair selenium mother to fetus transfer after the brazil nuts consumption.lactating mother and her two month old healthy daughter (apgar 10) gave their scalp hair for a multielement profile analysis; 25 elements were analyzed with the icp ms. mother's hair was divided into 5cm long segment proximal to the scull (young), and the distal segment further up to the hair tip (old). one centimeter of hair records one month of the metabolic activity of the bioelements in the body. mother's young hair and daughters hair have 2.70 and 9.74μgg(-1)se, a distinctly higher se conce ...201626653751
optimized extraction of polyphenolic antioxidant compounds from brazil nut (bertholletia excelsa) cake and evaluation of the polyphenol profile by hplc.the solid residue (cake) of pressed brazil nut oil has high energy value and contains high levels of nutrients and bioactive compounds, such as polyphenols. however, little is known about these components in this by-product. extraction is the first step in investigating the phenolic compounds in brazil nut cake because extraction conditions might impact the yields of phenolic compounds and antioxidant capacity. the aim of this study was to select the best phenolic compound extraction conditions ...201626353901
an apple plus a brazil nut a day keeps the doctors away: antioxidant capacity of foods and their health benefits.antioxidant-rich foods scavenge free radicals and other reactive species, decreasing the risk of different non-communicable chronic diseases. the objective of this study was to review the content of total antioxidant capacity of commonly foods comparing with experimental data and to explore the health benefits due to foods with moderate to high tac. the tac was analytically measured using the "total antioxidant capacity" (nx2332) test from randox® (uk) by spectrometry at 600 nm. brazil nut (bert ...201626572874
identification of aspergillus nomius in bees visiting brazil nut flowers.we designed a primer pair (btubnomf/btubnomr) specifically for amplifying aspergillus nomius dna. in vitro assays confirmed btubnomf/btubnomr specificity, corroborating its usefulness in detecting and identifying a. nomius. we then investigated the occurrence of a. nomius in floral visitors of bertholletia excelsa trees by means of pcr, and a. nomius was detected in the following bees: xylocopa frontalis, bombus transversalis, centris denudans, c. ferruginea, and epicharis flava. the presence of ...201526063353
ethnopharmacological evaluation of medicinal plants used against malaria by quilombola communities from oriximiná, brazil.malaria is the most important parasitic disease in the world, including in the amazon region, due to its high incidence. in addition, malaria is difficult to control because of the geographical characteristics of the endemic amazon region. the quilombola communities of oriximina, located in remote rainforest areas, have extensive experience with medicinal plants due to their close contact with and dependence on local biodiversity as a therapeutic resource. to search for active bioproducts agains ...201526231451
elemental composition of edible nuts: fast optimization and validation procedure of an icp-oes method.an inductively coupled plasma-optical emission spectrometry method for the speedy simultaneous detection of 19 elements in edible nuts (walnuts: juglans nigra; almonds: prunus dulcis; hazelnuts: corylus avellana; brazil nuts: bertholletia excelsa; cashews: anacardium occidentalle; pistachios: pistacia vera; and peanuts: arachis hypogaea) available on the serbian markets, was optimized and validated through the selection of instrumental parameters and analytical lines free from spectral interfere ...201525298065
nut production in bertholletia excelsa across a logged forest mosaic: implications for multiple forest use.although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (ntfp) extraction. brazil nut (bertholletia excelsa, lecythidaceae) is one of the world's most economically-important ntfp species extracted almost entirely from natural forests across the amazon basin. an obligate out-crosser, brazil nut flowers are pollinated by large-bodied ...201526271042
production and characterization of absorbent heat from the bark of residual brazil nut bark (bertholletia excelsa l.).the increasing efforts to reduce the environmental impact on the amazon's natural resources are focusing on watercourses that pass through effluents with high concentrations of heavy metals. the adsorption by absorbent is one of the methods used to remove metallic ions. in this assignment, the preparation of activated carbon from brazil nut bark (bertholletia excelsa l.), which is a waste material produced from the use of seeds in foodstuffs and cosmetics, is shown.201526150893
intake of partially defatted brazil nut flour reduces serum cholesterol in hypercholesterolemic patients--a randomized controlled trial.thyroid hormones can lower levels of atherogenic lipoproteins, and selenium is important in thyroid hormone homeostasis. we aimed to investigate the effects of a healthy diet associated with the brazil nut (bertholletia excelsa) in dyslipidemic and hypertensive patients.201526077768
effect of selenium supplementation via brazil nut (bertholletia excelsa, hbk) on thyroid hormones levels in hemodialysis patients: a pilot study.thyroid function depends on trace mineral selenium (se), being at the active center of the iodothyronine deiodinase that catalyzes the conversion of the thyroxine (t4) to the active form of thyroid hormone, triiodothyronine (t3). hemodialysis (hd) patients have reduced t3 levels partly due to impaired hormonal conversion that can be related to se deficiency, a common feature in these patients. this study evaluated the effect of brazil nuts (richest se source) on thyroid hormone levels in hd pati ...201526545554
floristic and phytosociology in dense "terra firme" rainforest in the belo monte hydroelectric plant influence area, pará, brazil.the objective of the present study was to characterise the floristic and phytosociological composition on a stretch of dense "terra firme" rainforest located in the belo monte hydroelectric plant area of influence, located in the state of pará, brazil. all trees with dap >10 cm situated in 75 permanent plots of 1 ha were inventoried. 27,126 individuals trees (361 ind.ha-1), distributed in 59 botanical families, comprising 481 species were observed. the families with the largest number of species ...201526691099
characterization of aspergillus section flavi isolated from organic brazil nuts using a polyphasic approach.brazil nut (bertholletia excelsa), an important non-timber forest product from amazonia, is commercialized in worldwide markets. the main importers of this nut are north america and european countries, where the demand for organic products has grown to meet consumers concerned about food safety. thus, the precise identification of toxigenic fungi is important because the brazil nut is susceptible to colonization by these microorganisms. the present study aimed to characterize by polyphasic appro ...201424929714
stereo and scanning electron microscopy of in-shell brazil nut (bertholletia excelsa h.b.k.): part two-surface sound nut fungi spoilage susceptibility.this work reports the in-shell brazil nut spoilage susceptible morpho-histological characteristics and fungi infection (shell, edible part, and brown skin) through stereo and scanning electron microscopies (sem). the following characteristics related to shell (a) morphology-that allow fungi and insects' entrance to inner nut, and (b) histology-that allow humidity absorption, improving environment conditions for living organisms development, were identified. (a.1) locule in testae-the nut navel, ...201425318846
anthropogenic landscape in southeastern amazonia: contemporary impacts of low-intensity harvesting and dispersal of brazil nuts by the kayapó indigenous people.brazil nut, the bertholletia excelsa seed, is one of the most important non-timber forest products in the amazon forest and the livelihoods of thousands of traditional amazonian families depend on its commercialization. b. excelsa has been frequently cited as an indicator of anthropogenic forests and there is strong evidence that past human management has significantly contributed to its present distribution across the amazon, suggesting that low levels of harvesting may play a positive role in ...201425029191
stereoscopy and scanning electron microscopy of brazil nut (bertholletia excelsa h.b.k.) shell, brown skin, and edible part: part one--healthy nut.in this article, tissue layers and cells characteristics of the brazil nut (bertholletia excelsa h.b.k.) shell (tegument), brown skin (testae), and edible part (cotyledons) were identified by stereoscopy (sm) and scanning electron microscopies (sem). (a) the shell (a lignin rich, protective wall) varies in thickness throughout the nut structure and comprises different tissue types (total 3)/texture (hard/mid-hard/soft), layers (2 to 5), colors (light to dark brown and white to cream), cell shape ...201424974969
brazil nut (bertholletia excelsa, h.b.k.) improves oxidative stress and inflammation biomarkers in hemodialysis patients.cumulative evidence indicates that oxidative stress and inflammation frequently occurs in patients undergoing maintenance hemodialysis (hd) and as a result of overproduction of reactive oxygen species (ros) and a decrease of antioxidant defenses such as selenium (se). previous studies in our laboratory showed that the supplementation of 1 unit of brazil nut (the richest known food source of se) a day during 3 months is effective to improve se status and increase glutathione peroxidase (gpx) leve ...201424504745
isolation and characterization of microsatellite markers for bertholletia excelsa (lecythidaceae) population genetic analysis.seven polymorphic microsatellite markers were developed and validated for bertholletia excelsa (brazil nut tree) population genetic studies. this species is a widespread monotypic amazonian tree with high non-timber economic value. unfortunately, brazil nut production is currently less than 25% of historical production levels, because of extensive deforestation. all pairs of primers produced clearly interpretable and polymorphic bands. no linkage disequilibrium was observed in an analysis of 46 ...201324301788
the relationship of selenium tolerance and speciation in lecythidaceae species.comparative study of selenium (se) speciation in hyperaccumulator plants offers an interesting challenge from the analytical point of view. in our study the application of a sophisticated sample clean-up procedure and the combination of elemental and molecular mass spectrometric methods led to the identification of several new selenocompounds. the difference between the se speciation of the primary accumulator lecythis minor and the secondary accumulator bertholletia excelsa confirmed the curren ...201324136350
selection of recombinant antibodies by phage display technology and application for detection of allergenic brazil nut (bertholletia excelsa) in processed foods.current immunological methods for detection of brazil nut allergens in foods are based on polyclonal antibodies raised in animals. phage display technology allows the procurement of high-affinity antibodies avoiding animal immunization steps and therefore attaining the principle of replacement supported by animal welfare guidelines. in this study, we screened tomlinson i and j libraries for specific binders against brazil nut by employing a brazil nut protein extract and a purified brazil nut 2s ...201324090075
morphological and molecular characteristics do not confirm popular classification of the brazil nut tree in acre, brazil.in the state of acre, the brazil nut tree, bertholletia excelsa (lecythidaceae), is classified by the local population into two types according to morphological characteristics, including color and quality of wood, shape of the trunk and crown, and fruit production. we examined the reliability of this classification by comparing morphological and molecular data of four populations of brazil nut trees from vale do rio acre in the brazilian amazon. for the morphological analysis, we evaluated qual ...201324089091
tradeoffs in basal area growth and reproduction shift over the lifetime of a long-lived tropical species.understanding of the extent to which reproductive costs drive growth largely derives from reproductively mature temperate trees in masting and non-masting years. we modeled basal area increment (bai) and explored current growth-reproduction tradeoffs and changes in such allocation over the life span of a long-lived, non-masting tropical tree. we integrated rainfall and soil variables with data from 190 bertholletia excelsa trees of different diameter at breast height (dbh) sizes, crown character ...201323404069
elemental composition and chemical characteristics of five edible nuts (almond, brazil, pecan, macadamia and walnut) consumed in southern africa.the total elemental concentrations and proximate chemical composition of five different tree nuts, almond (prunus dulcus), brazil (bertholletia excelsa), pecan (carya pecan), macadamia (macadamia integrifolia) and walnut (juglans nigra) that are consumed in south african households were investigated. in addition, six physicochemical properties of the extracted nut oils, namely acid value, iodine value, saponification value, refractive index, density and specific gravity were evaluated. a high co ...201317562467
monitoring and determination of fungi and mycotoxins in stored brazil nuts.brazil nut (bertholletia excelsa) is an important commodity from the brazilian amazon, and approximately 37,000 tons (3.36 × 10⁷ kg) of brazil nuts are harvested each year. however, substantial nut contamination by aspergillus section flavi occurs, with subsequent production of mycotoxins. in this context, the objective of the present investigation was to evaluate the presence of fungi and mycotoxins (aflatoxins and cyclopiazonic acid) in 110 stored samples of cultivated brazil nut (55 samples o ...201323905798
effect of brazil nut supplementation on the blood levels of selenium and glutathione peroxidase in hemodialysis patients.in patients who have undergone hemodialysis, large amounts of reactive oxygen species (ros) are produced and, at higher concentrations, ros are thought to be involved in the pathogenesis of cardiovascular disease. it has been proposed that selenium (se) may exert an antiatherogenic influence by reducing oxidative stress. the richest known food source of selenium is the brazil nut (bertholletia excelsa, family lecythidaceae), found in the amazon region. we evaluated the effect of brazil nut suppl ...201320018488
aspergillus bertholletius sp. nov. from brazil nuts.during a study on the mycobiota of brazil nuts (bertholletia excelsa) in brazil, a new aspergillus species, a. bertholletius, was found, and is described here. a polyphasic approach was applied using morphological characters, extrolite data as well as partial β-tubulin, calmodulin and its sequences to characterize this taxon. a. bertholletius is represented by nineteen isolates from samples of brazil nuts at various stages of production and soil close to bertholletia excelsa trees. the following ...201222952594
molecular analysis of aspergillus section flavi isolated from brazil nuts.brazil nuts are an important export market in its main producing countries, including brazil, bolivia, and peru. approximately 30,000 tons of brazil nuts are harvested each year. however, substantial nut contamination by aspergillus section flavi occurs with subsequent production of aflatoxins. in our study, aspergillus section flavi were isolated from brazil nuts (bertholletia excelsa), and identified by morphological and molecular means. we obtained 241 isolates from nut samples, 41% positive ...201222805966
effect of brazil nut supplementation on plasma levels of selenium in hemodialysis patients: 12 months of follow-up.large amounts of reactive oxygen species are produced in hemodialysis (hd) patients, and, at higher concentrations, reactive oxygen species are thought to be involved in the pathogenesis of cardiovascular disease. it has been proposed that selenium (se) may exert an antiatherogenic influence by reducing oxidative stress. the richest known food source of se is the brazil nut (bertholletia excelsa, family lecythidaceae), found in the amazon region.201222217537
brazil nuts intake improves lipid profile, oxidative stress and microvascular function in obese adolescents: a randomized controlled trial.obesity is a chronic disease associated to an inflammatory process resulting in oxidative stress that leads to morpho-functional microvascular damage that could be improved by some dietary interventions. in this study, the intake of brazil nuts (bertholletia excelsa), composed of bioactive substances like selenium, α- e γ- tocopherol, folate and polyunsaturated fatty acids, have been investigated on antioxidant capacity, lipid and metabolic profiles and nutritive skin microcirculation in obese a ...201121619692
effect of oxygen-reducing atmospheres on the safety of packaged shelled brazil nuts during storage.this work reports the application of oxygen-(o(2)-) reducing atmosphere methods on stored shelled brazil nut (bertholletia excelsa h.b.k.) packs aiming to evaluate the degree of aflatoxin degradation, nuts lipid oxidative stability, fungi control, and hygienic conditions improvement. the methods applied were (a) ozone: o(3), (b) carbon dioxide: co(2), and (c) o(2) absorber pads with and without vacuum. from all modified atmospheres evaluated, the best performance was obtained with o(3), either w ...201121760791
[pollinators of bertholletia excelsa (lecythidales: lecythidaceae): interactions with stingless bees (apidae: meliponini) and trophic niche].this paper presents an analysis of the foraging behavior and interactions of xylocopa frontalis olivier (apidae: xylocopini) and eulaema mocsaryi (friese) (apidae: euglossini) in the presence of stingless bees (apidae: meliponini) in flowers of bertholletia excelsa, the brazilian nut. the palynological load carried by both species was also examined. this study was conducted in the farm aruanã, itacoatiara/ amazonas state, brazil, during the flowering peak of b. excelsa. the visitation by the mai ...201121271049
purification and biochemical characterization of brazil nut (bertholletia excelsa l.) seed storage proteins.brazil nut storage proteins, 2s albumin, 7s vicilin, and an 11s legumin, were purified using column chromatography. analytical ultracentrifugation of the purified albumin, vicilin, and legumin proteins, respectively, registered sedimentation coefficients of 1.8, 7.1, and 11.8 s. under reducing conditions, the major polypeptide bands in 2s albumin were observed at 6.4, 10-11, and 15.2 kda. the 7s globulin was composed of one 12.6 kda, two approximately 38-42 kda, and two approximately 54-57 kda p ...201020405841
a novel, sensitive and specific real-time pcr for the detection of traces of allergenic brazil nut (bertholletia excelsa) in processed foods.food-allergic individuals have to strictly avoid the offending food because no causative immunotherapies are available. thus, reliable labelling of allergenic ingredients or precautionary labelling of cross-contacts with potential allergens is of major importance. verification of compliance with labelling requirements and identification of cross-contacts demand test methods that enable the specific and sensitive detection of the analyte. brazil nut (bertholletia excelsa) is such a food commodity ...201020730581
a novel real-time polymerase chain reaction method for the detection of brazil nuts in food.a qualitative real-time pcr-based method for the detection of the brazil nut (bertholletia excelsa) component in food is described. the method consists of dna isolation by chaotropic spe and the subsequent pcr with brazil nut-specific primers and a taqman fluorescent probe. the primers and the probe are targeted to the gene encoding for the 11s globulin of the brazil nut. the method was positive for eight brazil nut samples from the market and negative for all other tested plant and meat materia ...201020334181
a sensitive and robust competitive enzyme-linked immunosorbent assay for brazil nut ( bertholletia excelsa l.) detection.undeclared brazil nut residue in food products is of great concern because it can trigger life-threatening allergic reactions in sensitive patients. a rabbit polyclonal antibody-based competitive elisa (ic(50) = 23.2 +/- 9 ng/ml, n = 76) with good sensitivity, detection range of 10-90 ng/ml, was developed. the elisa could detect brazil nut seed proteins over a ph range of 5-12. the optimal ph range for the detection assay was 7-10. among the 66 tested foods/ingredients, only cinnamon exhibited s ...200919113944
first record of the coffee berry borer, hypothenemus hampei (ferrari) (coleoptera: scolytidae), in pará nut, bertholletia excelsa (lecythidaceae).we report the occurrence of hypothenemus hampei (ferrari) attacking pará nuts stored in the southeast of para state. the coffee berry borer successfully colonized and reproduced using pará nuts as a food source. based on this observation, the pará nuts can be used as an alternative food source in rearing the coffee berry borer. also, attention should be brought to need of proper storage of these nuts to avoid infestation by this pest.200919618062
development and characterization of microsatellite markers for the brazil nut tree bertholletia excelsa humb. & bonpl. (lecythidaceae).twelve polymorphic microsatellite markers were developed for the brazil nut (bertholletia excelsa), one of the most valuable non-timber forest products from the amazon, based on enrichment protocol. six to 18 (mean 10.4) alleles per locus were identified and the expected heterozygosity ranged from 0.663 to 0.923 based on a screen of 40 individuals from one population of b. excelsa. the combined probabilities of genetic identity (8.39 × 10(-17) ) and paternity exclusion (0.999999) indicated that ...200921564791
systematic study of high molecular weight compounds in amazonian plants by high temperature gas chromatography-mass spectrometry.the fractions of hexane and dichloromethane extraction from marupá (simaruba amara) and (bertholletia excelsa) leaves were analyzed by ht-hrgc (high temperature high resolution gas chromatography) and ht-hrgc coupled to mass spectrometry (ht-hrgc-ms). several compounds can be characterized including unusual high molecular weight compounds.200910817205
brazil nut ingestion increased plasma selenium but had minimal effects on lipids, apolipoproteins, and high-density lipoprotein function in human subjects.the brazil nut (bertholletia excelsa) of the amazon region is consumed worldwide. it is rich in both monounsaturated fatty acids and polyunsaturated fatty acids and is known for its high selenium content. this study tested the hypothesis whether the consumption of this nut could affect the plasma lipids and apolipoproteins and some functional properties of the antiatherogenic high-density lipoprotein (hdl). fifteen normolipidemic subjects aged 27.3 +/- 3.9 years and with body mass index of 23.8 ...200819083402
a search for phylogenetically informative wood characters within lecythidaceae s.l.the wood structure of 71 species representing 24 genera of the pantropical lecythidaceae s.l., including the edible brazil nuts (bertholletia excelsa) and the spectacular cannon-ball tree (couroupita guianensis), was investigated using light and scanning electron microscopy. this study focused on finding phylogenetically informative characters to help elucidate any obscure evolutionary patterns within the family. the earliest diverging subfamily napoleonaeoideae has mixed simple/scalariform vess ...200721636419
evolution of lecythidaceae with an emphasis on the circumscription of neotropical genera: information from combined ndhf and trnl-f sequence data.the lecythidaceae comprise a pantropical family best known for the edible seeds of the brazil nut (bertholletia excelsa) and the cannon-ball tree (couroupita guianensis), which is planted as a botanical curiosity in subtropical and tropical gardens. in addition, species of the family are often among the most common in neotropical forests, especially in the amazon basin. the brazil nut family is diverse and abundant in the amazon and is considered to be an indicator of undisturbed or scarcely dis ...200721636402
purification, crystallization and initial crystallographic characterization of brazil-nut allergen ber e 2.peanut and tree-nut allergies have attracted considerable attention because of their frequency and their lifelong persistence. brazil-nut (bertholletia excelsa) allergies have been well documented and the 11s legumin-like seed storage protein ber e 2 (excelsin) is one of the two known brazil-nut allergens. in this study, ber e 2 was extracted from brazil-nut kernels and purified to high purity by crystalline precipitation and gel-filtration chromatography. well diffracting single crystals were o ...200718007055
uptake of 2s albumin allergens, ber e 1 and ses i 1, across human intestinal epithelial caco-2 cell monolayers.we have investigated the absorption rates of two purified major allergen 2s albumins, ber e 1 from brazil nuts (bertholletia excelsa humb. & bonpl.) and ses i 1 from white sesame seeds (sesamum indicum l.), across human intestinal epithelial caco-2 cell monolayers following gastrointestinal digestion in vitro. the transport from apical to basolateral side in cell monolayers was evaluated by rp-hplc-uv and indirect competitive elisa methods, being confirmed by western-blotting analysis. significa ...200617061844
trypanocidal activity of extracts and fractions of bertholletia excelsa.crude extracts and fractions of bertholletia excelsa stem barks were tested for trypanocidal activity. acetone and methanol extracts showed significant in vitro trypanocidal activity against trypomastigote form of trypanosoma cruzi since in the concentration of 500 microg/ml, the parasites were reduced in 100% and 90.3% respectively, whereas the triterpene betulinic acid pure isolated from hexane extract presented 75.4%.200515664458
functionality of succinylated brazil nut (bertholletia excelsa hbk) kernel globulin.one of the possible ways to improve the utilisation of defatted brazil nut kernel flour, a by-product of oil extraction industries, is to improve its functional properties by chemical modification as it possesses very modest functional characteristics. succinylated brazil nut kernel globulin at 55.8%, 62.4% and 72.0% level showed a positive effect on functionality. the solubility of acylated globulin was improved above ph 4.0 but was reduced in the ph range of 3.0-4.0. water absorption (1.96-4.0 ...200515898352
studying the distribution pattern of selenium in nut proteins with information obtained from sec-uv-icp-ms and ce-icp-ms.in this work, size exclusion chromatography (sec) with uv and inductively coupled plasma mass spectrometry (icp-ms) detection was used to study the association of selenium to proteins present in brazil nuts (bertholletia excelsa) under five different extraction conditions. as expected, better solubilization of proteins was observed using 0.05moll(-1) sodium hydroxide and 1% sodium dodecylsulfate (sds) in tris/hcl buffer (0.05moll(-1), ph 8) as compared to 0.05moll(-1) hcl, 0.05moll(-1) tris/hcl ...200518969975
studies of various elements of nutritional and toxicological interest associated with different molecular weight fractions in brazil nuts.on-line hyphenation of size exclusion chromatography (sec), uv, and inductively coupled plasma mass spectrometry (icp-ms) was used to study the molecular weight distribution patterns of several elements in brazil nuts (bertholletia excelsa). this technique was used for the elemental speciation of different elements of nutritional and toxicological interests such as mg, fe, co, mo, ag, hg, and pb. elemental fractionation in brazil nuts was studied using a superdex peptide column with resolving ca ...200415366819
study of selenium distribution in the protein fractions of the brazil nut, bertholletia excelsa.the high selenium content of the brazil nut, bertholletia excelsa, makes this seed a healthy food qualified as an antiradical protector. the studied nut contained 126 ppm of selenium. selenium was found to be distributed in the nut protein fractions. the water-extracted fraction, which represented 17.7% of the cake protein, was the richest in selenium with 153 ppm. analysis by hplc-ms showed that selenium was linked by a covalent bond to two amino acids to form selenomethionine and selenocystine ...200415212486
mass spectrometry and structural characterization of 2s albumin isoforms from brazil nuts (bertholletia excelsa).proteomic approaches have been used to characterise the main 2s albumin isoforms from brazil nuts (bertholletia excelsa). whilst most isoforms ( approximately 10 discrete protein species) exhibited molecular masses of around 12 kda with a high amino acid sequence homology, important charge heterogeneity was found, with pis varying between 4.6 and 6.6, with one >or=7.0. proteomic analysis showed that these corresponded to a total of six national center for biotechnology information (ncbi) accessi ...200415134650
sustainability in a nutshell.sustainable exploitation is widely advocated as a strategy for reconciling economic pressures upon natural habitats with nature conservation. two recent papers examine different aspects of the sustainability of the nut harvest on wild populations of brazil nut trees bertholletia excelsa in amazonia. peres et al. find that many populations of the brazil nut tree lack juvenile trees and are not regenerating. in a socioeconomic study, escobal and aldana find that nut-gathering provides insufficient ...200416701269
allergens from brazil nut: immunochemical characterization.the increase in the consumption of tropical nuts in the northern hemisphere during the last years, has evolved in a simultaneous enhancement of allergic ige mediated (hypersensitivity type 1) reported cases produced by this kind of food. the brazil nut is the seed of the bertholletia excelsa tree (family lecythidaceae) and, as in other seeds, proteins represent one of its major components making up 15-17% of its fresh weight and 50% of defatted flour. of these, storage proteins are the most impo ...20049208050
preparation, homogeneity and stability studies of a candidate lrm for se speciation.a laboratory reference material (lrm) was prepared from brazil nuts (bertholletia excelsa) for quality control (qc) purposes of selenium speciation. the preparation of this lrm led through the usual operation steps applied during routine reference material production from biota samples-preparation of the raw material, homogenisation, storage design, checking of homogeneity, microbiological status and possible irradiation effects, and monitoring the species stability vs time at different storage ...200312750870
demographic threats to the sustainability of brazil nut exploitation.a comparative analysis of 23 populations of the brazil nut tree (bertholletia excelsa) across the brazilian, peruvian, and bolivian amazon shows that the history and intensity of brazil nut exploitation are major determinants of population size structure. populations subjected to persistent levels of harvest lack juvenile trees less than 60 centimeters in diameter at breast height; only populations with a history of either light or recent exploitation contain large numbers of juvenile trees. a h ...200314684819
tomato ribonuclease lx with the functional endoplasmic reticulum retention motif hdef is expressed during programmed cell death processes, including xylem differentiation, germination, and senescence.we have studied the subcellular localization of the acid s-like ribonuclease (rnase) lx in tomato (lycopersicon esculentum mill.) cells using a combination of biochemical and immunological methods. it was found that the enzyme, unexpectedly excluded from highly purified vacuoles, accumulates in the endoplasmic reticulum. the evidence that rnase lx is a resident of the endoplasmic reticulum (er) is supported by an independent approach showing that the c-terminal peptide hdef of rnase lx acts as a ...200111598219
effect of pyrolysis temperature on composition, surface properties and thermal degradation rates of brazil nut shells.changes in chemical and surface characteristics of brazil nut shells (bertholletia excelsa) due to pyrolysis at different temperatures (350 degrees c, 600 degrees c, 850 degrees c) were examined. for this purpose, proximate and ultimate analyses, physical adsorption measurements of n2 (-196 degrees c) and co, (25 degrees c) as well as samples visualisation by scanning electronic microscopy (sem) were performed. appreciable differences in the residue characteristics, depending markedly on the pyr ...200111315805
antioxidant concentration effect on stability of brazil nut (bertholletia excelsa) crude oil.shelled and broken brazil nuts easily lose quality, if not properly stored. pressing is an alternative use of these nuts and the crude oil stability was studied. our previous studies demonstrated that tbhq (200 mg kg-1) was very efficient to prevent rancidity development in oils bottled in brown and clear glass. as tbhq has higher price than other phenolic antioxidants like bht and bha, an oven test (at 63 degrees c) was conducted to determine the economical and best concentration of tbhq for br ...199910667268
isolation and primary structure of a methionine- and cystine-rich seed protein of cannabis sativa.a 10-kda protein was isolated from resting seeds of hemp (cannabis sativa) by buffer extraction, gel filtration, ion-exchange chromatography, and reversed-phase high-pressure liquid chromatography. the protein did not inhibit bovine trypsin. it consisted of subunits composed of 27 and 61 residues and was held together by two disulfide bonds. the complete amino acid sequence was identified by protein analysis, and had 20 mole% of amino acids containing sulfur. the protein was most similar to a me ...19989614695
cloning and sequencing of a gene encoding a 2s albumin seed storage protein precursor from english walnut (juglans regia), a major food allergen.walnuts rank third in per capita consumption of tree nuts in the united states and can be associated with systemic ige-mediated reactions in some individuals.19989648708
the vacuolar targeting signal of the 2s albumin from brazil nut resides at the c terminus and involves the c-terminal propeptide as an essential element.genetic constructs in which different n- and c-terminal segments of brazil nut (bertholletia excelsa h.b.k.) 2s albumin were fused to secretory yeast invertase were transformed into tobacco (nicotiana tabacum) plants to investigate the vacuolar targeting signal of the 2s albumin. none of the n-terminal segments, including the complete precursor containing all propeptides, was able to direct the invertase to the vacuoles. however, a short c-terminal segment comprising the last 20 amino acids of t ...19968938406
cloning and sequencing of a cdna encoding a heat-stable sweet protein, mabinlin ii.a cdna clone encoding a heat-stable sweet protein, mabinlin ii (mab), was isolated and sequenced. the encoded precursor to mab was composed of 155 amino acid (aa) residues, including a signal sequence of 20 aa, an n-terminal extension peptide of 15 aa, a linker peptide of 14 aa and one residue of c-terminal extension. comparison of the proteolytic cleavage sites during post-translational processing of mab precursor with those of like 2s seed-storage proteins of arabidopsis thaliana, brassica nap ...19968973336
interaction of a potential vacuolar targeting receptor with amino- and carboxyl-terminal targeting determinants.a protein of 80 kd from developing pea (pisum sativum) cotyledons has previously been shown to exhibit characteristics of a vacuolar targeting receptor by means of its affinity for the amino-terminal vacuolar targeting sequence of proaleurain from barley (hordeum vulgare). in this report we show that the same protein also binds to the amino-terminal targeting peptide of prosporamin from sweet potato (ipomoea batatas) and to the carboxyl-terminal targeting determinant of pro-2s albumin from brazi ...19968787025
selenium content of brazil nuts from two geographic locations in brazil.brazil nuts (bertholletia excelsa) natively contain very high concentrations of selenium. since dietary selenium, including brazil nuts, have been associated with protection against tumor development in laboratory animal studies, it was of interest to determine the selenium content of the nuts from different nut-growing regions of brazil. in the work reported, 162 nuts from each of two regions (acre-rondonia and manaus-belem) were individually analyzed for selenium. the average +/- standard devi ...19957889353
bioactivity of selenium from brazil nut for cancer prevention and selenoenzyme maintenance.brazil nut (bertholletia excelsa) is one of very few consumable products with exceptionally high levels of selenium. the mean selenium concentrations of two shipments of brazil nut used in the present study were determined to be 16 and 30 micrograms/g. in contrast, most common foods contain much less selenium, from 0.01 to 1 micrograms/g. previous research on selenium cancer chemoprevention invariably used a pure compound, whereas little information is available on the efficacy of selenium deliv ...19948072875
a chimeric gene encoding the methionine-rich 2s albumin of the brazil nut (bertholletia excelsa h.b.k.) is stably expressed and inherited in transgenic grain legumes.the coding region of the 2s albumin gene of brazil nut (bertholletia excelsa h.b.k.) was completely synthesized, placed under control of the cauliflower mosaic virus (camv) 35s promoter and inserted into the binary vector plasmid pgsgluc1, thus giving rise to pgsgluc1-2s. this was used for transformation of tobacco (nicotiana tabacum l. cv. petit havanna) and of the grain legume vicia narbonensis l., mediated by the supervirulent agrobacterium tumefaciens strain eha 101. putative transformants w ...19948159174
stabilization of methionine-rich protein in saccharomyces cerevisiae: targeting of bzn protein into the peroxisome.we have constructed a gene coding for the 12-kda intermediate form of the 2s methionine-rich protein from bertholletia excelsa seeds. this protein, expressed intracellularly in yeast, is characterised by a 20-min half-life. by adding 11 amino acids corresponding to the peroxisome-targeting sequence (ptsc) of luciferase, we have significantly increased its half-life. this stabilization allowed accumulation of the bzn protein into the peroxisome as judged by cell fractionation. accumulation of the ...19947874730
isolation, characterization and expression of a gene coding for a 2s albumin from bertholletia excelsa (brazil nut).two genes, be2s1 and be2s2, coding for methionine-rich albumins of brazil nut (bertholletia excelsa h.b.k.) have been cloned and their sequence determined. the genes are members of a multigene family and one of them, i.e. be2s1, codes for one of the dominant 2s isoforms. its expression is highly regulated during seed development and with respect to tissue specificity. sequence analysis has shown that the genes contain one intron and that the promoter of be2s1 shows a canonical tata motif. the tr ...19911840683
expression of the 2s albumin from bertholletia excelsa in brassica napus.the methionine rich 2s albumin seed storage protein of bertholletia excelsa has been expressed in seeds of brassica napus (rapeseed). a chimeric gene driven by the soybean lectin 5' flanking regions was used to produce a fusion protein consisting of the soybean lectin signal peptide and the propeptide of the brazil nut 2s albumin. several transgenic plants were studied at the rna and protein levels; in each case the chimeric gene was expressed and the protein detected at levels ranging from 0.02 ...19902381415
genetics of brazil nut (bertholletia excelsa humb. & bonpl.: lecythidaceae) : 2. mating system.here we report the results of a mating system analysis of an amazonian population of bertholletia excelsa, a tropical rain forest canopy tree species. using progeny data from 29 seed parents, two highly polymorphic isozymes were analyzed to derive single locus and multilocus estimates of outcrossing, based on a mixed mating model. the two single locus estimates were very similar, and both were somewhat smaller than the multilocus estimate, indicating the possibility that the populations are gene ...198824232406
genetics of brazil nut (bertholletia excelsa humb. & bonpl.: lecythidaceae) : 1. genetic variation in natural populations.we provide an estimate of genetic variation within and between two populations of bertholletia excelsa (brazil nut), a large canopy tree found in the rain forests of south america. average heterozygosity is 0.190, and 54.3% of the sampled loci are polymorphic. the population structure deviates significantly from hardy-weinberg expectations for fest2 and pgm2 (f =0.405 and 0.443, respectively) in one population, and highly significantly (f=-0.341) for gdh in the other population. although allele ...198824232405
determination of the processing sites of an arabidopsis 2s albumin and characterization of the complete gene family.the most abundant isoform of the 2s albumin present in seeds of arabidopsis thaliana has been sequenced and the corresponding gene isolated. examination of the protein and dna sequences allows the determination of the exact proteolytic cleavage sites during posttranslational processing. like other 2s albumins, that of arabidopsis is made as a prepropeptide. after removal of the signal peptide, the propeptide is cleaved at four other points, giving two subunits linked by a disulfide bridge(s). co ...198816666238
cloning and sequence analysis of a cdna encoding a brazil nut protein exceptionally rich in methionine.the primary amino acid sequence of an abundant methionine-rich seed protein found in brazil nut (bertholletia excelsa h.b.k.) has been elucidated by protein sequencing and from the nucleotide sequence of cdna clones. the 9 kda subunit of this protein was found to contain 77 amino acids of which 14 were methionine (18%) and 6 were cysteine (8%). over half of the methionine residues in this subunit are clustered in two regions of the polypeptide where they are interspersed with arginine residues. ...198724301128
properties, biosynthesis and processing of a sulfur-rich protein in brazil nut (bertholletia excelsa h.b.k.).an abundant seed protein, which is exceptionally rich in the sulfur-containing amino acids, methionine (18%) and cysteine (8%), is synthesized in brazil nut embryos about 9 months after flowering. this sulfur-rich protein consists of two low-molecular-mass polypeptide components, a 9-kda polypeptide and a 3-kda polypeptide. the two-subunit polypeptides associate through disulfide linkage(s) to form a 12-kda protein molecule. we have demonstrated through in vitro translation studies, using rna fr ...19873830150
the amino-acid sequence of the 2s sulphur-rich proteins from seeds of brazil nut (bertholletia excelsa h.b.k.).storage proteins of the albumin solubility fraction from seeds of bertholletia excelsa h.b.k. were separated by reversed-phase high-performance liquid chromatography and their primary structures were determined by gas-phase sequencing on intact polypeptides and on the overlapping tryptic and thermolysin peptides. the 2s storage proteins consist of two subunits linked by disulphide bridges. the large subunit (8.5 kda) is expressed in at least six different isoforms while the small subunit (3.6 kd ...19863758080
trace nutrients. selenium in british food.1. the amount of selenium in nationally representative samples of prepared and cooked groups of foods, and in a variety of raw individual foods, was determined fluorimetrically. 2. the average british diet was calculated to provide approximately 60 microgram se/d, of which half was derived from cereals and cereal products and another 40% from meat and fish. milk, table fats, fruit and vegetables provided little or no se. 3. individual foods which were particularly rich in se (greater than 0.2 mg ...1978629926
[nutritional problems which the campaign against protein malnutrition poses in underdeveloped countries. iv. the amino acid content of the brazil nut, bertholletia excelsa (humb. and bonpl.): an important source of methionine in northeast brazil]. 196314016731
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