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1.
Nutr Rev ; 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38481025

ABSTRACT

Brazil nut (Bertholletia excelsa H.B.K.) is characterized by its high nutritional and energetic value. It contains high levels of l-arginine, antioxidant vitamins, phenolic compounds, and phytosterols. In addition to their biological functions, bioactive compounds and essential fatty acids present therapeutic effects on chronic disease prevention through their antioxidant effects. Thus, this review aims to present the most recent scientific evidence on the effect of Brazil nut on human health. A search for scientific articles was carried out through the MEDLINE/PubMed, Science Direct, and LILACS databases, considering articles published between the years 2010 and 2023. The results showed that Brazil nuts and Brazil nut oil, when consumed regularly and associated with a balanced diet, can improve lipid profile, attenuate inflammatory response, and improve oxidative stress through increased activity and gene expression of antioxidant enzymes. However, further studies are recommended to better understand the mechanisms of action.

2.
Proc Natl Acad Sci U S A ; 121(6): e2307061121, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38285942

ABSTRACT

Industrial and environmental granular flows commonly exhibit a phenomenon known as "granular segregation," in which grains separate according to physical characteristics (size, shape, density), interfering with industrial applications (cement mixing, medicine, and food production) and fundamentally altering the behavior of geophysical flows (landslides, debris flows, pyroclastic flows, riverbeds). While size-induced segregation has been well studied, the role of grain shape has not. Here we conduct numerical experiments to investigate how grain shape affects granular segregation in dry and wet flows. To isolate the former, we compare dry, bidisperse mixtures of spheres alone with mixtures of spheres and cubes in a rotating drum. Results show that while segregation level generally increases with particle size ratio, the presence of cubes decreases segregation levels compared to cases with only spheres. Further, we find differences in the segregation level depending on which shape makes up each size class, reflecting differences in mobility when smaller grains are cubic or spherical. We find similar dynamics in simulations of a shear-driven coupled fluid-granular flow (e.g., a simulated riverbed), demonstrating that this phenomenon is not unique to rotating drums; however, in contrast to the dry system, we find that the segregation level increases in the presence of cubic grains, and fluid drag effects can qualitatively change segregation trends. Our findings demonstrate competing shape-induced segregation patterns in wet and dry flows that are independent from grain size controls, with implications for many industrial and geophysical processes.

3.
Int J Cosmet Sci ; 2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38229481

ABSTRACT

OBJECTIVE: The Amazon has a rich biodiversity where many different plant species can be found. This diversity is an important source of bioactive substances, mainly due to the different structural components of their phytometabolites. Research for natural products is a strategy for the development of new agents in therapeutic applications, especially cosmetic applications, that have better pharmacological potential. Within this perspective, the objective of the study was to investigate the cosmetic application (anti-aging potential) of the stem-bark extract of Bertholletia excelsa H.B.K - (SBEBE), popularly known as the Brazil nut tree, here called SBEBE, a noble plant species of the Amazon that is rich in selenium. METHODS: Enzymatic, glycation, proliferation, cell-healing, collagen quantification, toxicity and genotoxicity assays were used. RESULTS: Among the enzymes involved in the extracellular matrix of the skin, SBEBE was able to inhibit only elastase (62.67 ± 3.75) when compared to the standard sivelestat (89.04 ± 0.53), and the extract was also able to inhibit both the oxidative and the non-oxidative pathway. When cell toxicity in fibroblasts (MRC-5) and keratinocytes (HACAT) was evaluated, SBEBE did not present toxicity in 24 h of incubation. After this period, the extract showed average cytotoxicity in 48 and 72 h, but not enough to reach the concentration of 50% of MRC-5 fibroblasts. In the trypan blue assay, the extract promoted fibroblast proliferation in 24, 48 and 72 h of incubation, which was evaluated through exponential cell growth, with emphasis mainly on the lowest concentration with results higher than the standard. When the cell healing capacity was evaluated, in 48 h of exposure to fibroblast, SBEBE was able to induce a cell carpet (cell film) in the cell monolayer scratch assay. CONCLUSIONS: SBEBE stimulated collagen production at all concentrations tested. In the alkaline comet assay, at the lowest concentration, the extract did not induce DNA damage when compared to the reference drug doxorubicin. This study proved that SBEBE extract can be considered an ally in the treatment of skin anti-ageing as a possible biotechnological, phytocosmetic product.


OBJECTIF: L'Amazonie possède une riche biodiversité ou l'on trouve de nombreuses espèces végétales différentes. Cette diversité constitue une source importante de substances bioactives, principalement en raison des différents composants structurels de leurs phytométabolites. La recherche de produits naturels est une stratégie de développement de nouveaux agents à applications thérapeutiques, notamment cosmétiques, présentant un meilleur potentiel pharmacologique. Dans cette perspective, l'objectif de l'étude était d'étudier l'application cosmétique (potentiel anti-âge) de l'extrait d'écorce de tige de Bertholletia excelsa H.B.K - (SBEBE), communément connu sous le nom de noix du Brésil, ici appelé SBEBE, un arbre noble, espèce végétale d'Amazonie riche en sélénium. MÉTHODES: Des tests enzymatiques, de glycation, de prolifération, de guérison cellulaire, de quantification du collagène, de toxicité et de génotoxicité ont été utilisés. RÉSULTATS: Parmi les enzymes impliquées dans la matrice extracellulaire de la peau, le SBEBE était capable d'inhiber uniquement l'élastase (62,67 +- 3,75) par rapport au sivelestat standard (89,04 +- 0,53), et l'extrait était également capable d'inhiber à la fois la voie oxydative et non-oxydative. Lorsque la toxicité cellulaire dans les fibroblastes (MRC-5) et les kératinocytes (HACAT) a été évaluée, SBEBE n'a présenté aucune toxicité en 24 heures d'incubation. Après cette période, l'extrait a montré une cytotoxicité moyenne en 48 et 72 h, mais pas suffisamment pour atteindre la concentration de 50 % de fibroblastes MRC-5. Dans le test au bleu trypan, l'extrait a favorisé la prolifération des fibroblastes en 24, 48 et 72 heures d'incubation, qui a été évaluée par une croissance cellulaire exponentielle, en mettant l'accent principalement sur la concentration la plus faible avec des résultats supérieurs à la norme. Lorsque la capacité de guérison cellulaire a été évaluée, en 48 heures d'exposition aux fibroblastes, SBEBE a pu induire un tapis cellulaire (film cellulaire) dans le test de grattage de la monocouche cellulaire. CONCLUSIONS: SBEBE a stimulé la production de collagène à toutes les concentrations testées. Dans le test alcalin des comètes, à la concentration la plus faible, l'extrait n'a pas induit de dommages à l'ADN par rapport au médicament de référence, la doxorubicine. Cette étude a prouvé que l'extrait de SBEBE peut être considéré comme un allié dans le traitement anti-âge cutané en tant que possible produit biotechnologique et phytocosmétique.

4.
J Am Nutr Assoc ; 43(2): 201-212, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37611162

ABSTRACT

Introduction: Chronic kidney disease (CKD) promotes gut dysbiosis, and enteric glial reactivity, a feature of intestinal inflammation. Brazil nut modulated enteric glial profile in healthy animals and could modulate these cells in 5/6 nephrectomized rats.Methods: A 5/6 nephrectomy-induced CKD and Sham-operated rats were divided as follows: CKD and Sham received a standard diet and CKD-BN and Sham-BN received a 5% Brazil nut enriched-diet. The protein content of glial fibrillary acid protein (GFAP), enteric glial marker, and GPx protein content and activity were assessed in the colon. The major phyla of gut microbiota were assessed.Results: CKD-BN group presented a decrease in GFAP content (p = 0.0001). The CKD-BN group modulated the abundance of Firmicutes, increasing its proportion compared to the CKD group. The CKD-BN group showed increased GPx activity in the colon (p = 0.0192), despite no significant difference in protein content.Conclusion: Brazil nut-enriched diet consumption decreased enteric glial reactivity and modulated gut microbiota in the CKD experimental model.


Subject(s)
Bertholletia , Gastrointestinal Microbiome , Renal Insufficiency, Chronic , Rats , Animals , Diet , Neuroglia/metabolism , Renal Insufficiency, Chronic/metabolism
5.
Biomimetics (Basel) ; 8(7)2023 Oct 26.
Article in English | MEDLINE | ID: mdl-37999150

ABSTRACT

Dry fruits and nutshells are biological capsules of outstanding toughness and strength with biomimetic potential to boost fiber-reinforced composites and protective structures. The strategies behind the Betholletia excelsa fruit mechanical performance were investigated with C-ring and compression tests. This last test was monitored with shearography and simulated with a finite element model. Microtomography and digital and scanning electron microscopy evaluated crack development. The fruit geometry, the preferential orientation of fibers involved in foam-like sclereid cells, promoted anisotropic properties but efficient energy dissipating mechanisms in different directions. For instance, the mesocarp cut parallel to its latitudinal section sustained higher forces (26.0 ± 2.8 kN) and showed higher deformation and slower crack propagation. The main toughening mechanisms are fiber deflection and fiber bridging and pullout, observed when fiber bundles are orthogonal to the crack path. Additionally, the debonding of fiber bundles oriented parallel to the crack path and intercellular cracks through sclereid and fiber cells created a tortuous path.

6.
Microorganisms ; 11(7)2023 Jun 30.
Article in English | MEDLINE | ID: mdl-37512901

ABSTRACT

The Amazonian rainforest is a hyper-diverse ecosystem in the number of species and the myriad of intertaxon relationships that are mostly understudied. In order to characterize a dominant and economically important Amazonian species, the Brazil nut tree (Bertholletia excelsa Bonpl.), at the genome level, wegenerated high-coverage long-read sequencing data from the leaves of a single individual. The genome assembly revealed an unexpected discovery: two circular contigs that could be assigned to the chromosome and a plasmid of a Pantoea stewartii strain. Comparative genomics revealed that this strain belongs to the indologenes subspecies and displays high synteny with other strains isolated from diseased leaves of the neotropical palm Bactris gasipaes Kunth. Investigation of pathogenicity-related genes revealed the absence of the entire type III secretion system gene cluster in the plasmid, which was otherwise highly similar to a plasmid from an isolate known to cause disease in Dracaena sanderiana Mast. In contrast, several genes associated with plant-growth promoting traits were detected, including genes involved in indole-3-acetic acid (IAA) production, phosphate solubilization, and biosynthesis of siderophores. In summary, we report the genome of an uncultivated P. stewartii subsp. indologenes strain associated with the Brazil nut tree and potentially a plant growth-promoting bacteria.

7.
Molecules ; 28(12)2023 Jun 09.
Article in English | MEDLINE | ID: mdl-37375230

ABSTRACT

High-pressure homogenization (HPH) is an emerging technology for obtaining physical and microbial stability of plant-based milks, but there is little information on the effects of this technology on the phytochemical components of the processed plant food beverage and during its cold storage. The effect of three selected HPH treatments (180 MPa/25 °C, 150 MPa/55 °C, and 50 MPa/75 °C) and pasteurization (PAS) (63 °C, 20 min) on minor lipid constituents, total proteins, phenolic compounds, antioxidant capacity, and essential minerals of Brazil nut beverage (BNB) were studied. Additionally, the study of the possible changes in these constituents was carried out during cold storage at 5 °C for 21 days. The fatty acid profile (dominated by oleic acid and linoleic acid), free fatty acid content, protein, and essential minerals (notable source of Se and Cu) of the processed BNB remained almost stable to treatments (HPH and PAS). Specifically, reductions in squalene (22.7 to 26.4%) and γ-γ-tocopherol (28.4 to 36%) were observed in beverages processed via both non-thermal HPH and thermal PAS, but ß-sitosterol remained unchanged. Total phenolics were reduced (24 to 30%) after both treatments, a factor that influenced the observed antioxidant capacity. The studied individual phenolics in BNB were gallic acid, catechin, epicatechin, catechin gallate, and ellagic acid, being the most abundant compounds. During cold storage (5 °C) up to 21 days, changes in the content of phytochemicals, minerals, and total proteins were not noticeable for any treated beverages, and no lipolysis processes were promoted. Therefore, after the application of HPH processing, Brazil nut beverage (BNB) maintained almost unaltered levels of bioactive compounds, essential minerals, total protein, and oxidative stability, remarkable characteristics for its potential development as a functional food.


Subject(s)
Antioxidants , Bertholletia , Antioxidants/analysis , Beverages/analysis , Pasteurization , Minerals , Phenols
8.
Appl Physiol Nutr Metab ; 48(10): 789-798, 2023 Oct 01.
Article in English | MEDLINE | ID: mdl-37311253

ABSTRACT

Nuts are important sources of antioxidants that combat oxidative stress and improve lipid profile as well as vascular function. However, the intake of typical Brazilian nuts and its acute effect on cardiovascular health needs to be better understood. Thus, the present study aimed to evaluate the acute effect of a beverage containing cashew (Anacardium occidentale L.) and Brazil nuts (Bertholletia excelsa H.B.K.) on postprandial oxidative stress, lipemia, and blood pressure of adult women aged 20 to 55 years with cardiometabolic risk. This was an acute, randomized, parallel arm, controlled clinical trial. The participants received either a beverage containing nuts (30 g Brazil nuts + 15 g cashew nuts) or a beverage without nuts with similar macronutrient composition. Oxidative stress markers and lipid profiles were evaluated at fasting and 4 h after beverage consumption. Blood pressure was measured during fasting and after beverage intake (1, 2, 3, and 4 h). In the postprandial state, there was a greater reduction in malondialdehyde levels in the intervention group compared to the control group (-12.3 ± 0.59 vs. -10.7 ± 0.43 µmol/mL; p < 0.05), which was positively correlated with the concentrations of TG (r = 0.399; p < 0.05), VLDL (r = 0.399; p < 0.05), TG/HDL (r = 0.380; p < 0.05), and blood pressure (iAUC SBP r = 0.391; p < 0.05, iAUC DBP r = 0.409; p < 0.05). The remaining oxidative stress markers showed similar postprandial changes between groups. In women with cardiometabolic risk, a beverage containing Brazilian nuts promoted a significant acute reduction on postprandial malondialdehyde levels. The study was registered in the Brazilian Clinical Trials Registry-ReBEC (protocol: RBR-3ntxrm).


Subject(s)
Anacardium , Cardiovascular Diseases , Hyperlipidemias , Adult , Humans , Female , Nuts , Blood Pressure , Brazil , Oxidative Stress , Lipids , Cardiovascular Diseases/prevention & control , Malondialdehyde
9.
Polymers (Basel) ; 15(9)2023 Apr 23.
Article in English | MEDLINE | ID: mdl-37177145

ABSTRACT

This work evaluates for the first time the potential of an environmentally friendly plasticizer derived from epoxidized Brazil nut oil (EBNO) for biopolymers, such as poly(lactic acid) (PLA). EBNO was used due to its high epoxy content, reaching an oxirane oxygen content of 4.22% after 8 h of epoxidation for a peroxide/oil ratio of 2:1. Melt extrusion was used to plasticize PLA formulations with different EBNO contents in the range of 0-10 phr. The effects of different amounts of EBNO in the PLA matrix were studied by performing mechanical, thermal, thermomechanical, and morphological characterizations. The tensile test demonstrated the feasibility of EBNO as a plasticizer for PLA by increasing the elongation at break by 70.9% for the plasticized PLA with 7.5 phr of EBNO content in comparison to the unplasticized PLA. The field-emission scanning electron microscopy (FESEM) of the fractured surfaces from the impact tests showed an increase in porosity and roughness in the areas with EBNO addition, which was characteristic of ductile failure. In addition, a disintegration test was performed, and no influence on the PLA biodegradation process was observed. The overall results demonstrate the ability of EBNO to compete with other commercial plasticizers in improving the ductile properties of PLA.

10.
Biol Trace Elem Res ; 201(3): 1112-1117, 2023 Mar.
Article in English | MEDLINE | ID: mdl-35488024

ABSTRACT

Brazil nut (BN) is a good source of essential nutrients, but little is known about the content of other components, such as toxic elements. Moreover, the high consumption of BN could probably contribute to increased levels of toxic and essential elements in the blood. Thus, this study aimed to evaluate the concentration of essential and toxic trace elements in BN and their concentration in plasma of obese women after regular intake of BN. A randomized controlled clinical trial was carried out with 55 subjects that were randomly assigned to either the Brazil nut group (BN) (n = 29) or the control group (CO) (n = 26) and followed up for 2 months. The BN group consumed one unit of Brazil nut per day, and the CO group did not receive any intervention. The concentration of essential elements (zinc, copper, manganese, and cobalt) and toxic (barium, lead, and cadmium) in BN samples and plasma of obese women (before and after the intervention) were determined by inductively coupled plasma mass spectrometry. Barium followed by copper, and manganese were the trace elements present in higher amounts in Brazil nuts. After the BN intervention period was observed an increase in plasma cadmium (p = 0.002) and a reduction of plasma manganese (p < 0.001) levels. In conclusion, our findings suggest that the regular consumption of BN from the Brazilian Amazon rainforest contributes to the intake of essential trace elements and can be considered safe regarding the content of heavy metals.


Subject(s)
Bertholletia , Trace Elements , Female , Humans , Trace Elements/analysis , Manganese/analysis , Copper/analysis , Cadmium/analysis , Barium , Obesity
11.
J Dev Orig Health Dis ; 14(6): 795-804, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38345286

ABSTRACT

Maternal obesity may trigger long-term neurodevelopmental disorders in offspring. Considering the benefits of the Brazil nut (Bertholletia excelsa H.B.K.), a rich source of nutrients such as selenium, this study aimed to evaluate its effect on the behavior of obese rat offspring and its relationship with oxidative stress. From 60 days of age until weaning, female Wistar rats were fed a high-fat diet (mHF) or an HF diet supplemented with 5% Brazil nut (mHF/BN), while control mothers (mCTL) were fed a standard diet or a standard diet supplemented with 5% Brazil nut (mBN). Male pups received a standard diet throughout life and, at 30 and 90 days old, were subjected to behavioral tasks to evaluate anxiety and cognition. Biochemical evaluations were performed at 90 days of age. No alterations were observed in the anxiety behavior of the offspring. However, the offspring of the mHF group (oHF) exhibited impaired short-term memory at 30 and 90 days of age and impaired long-term memory at 30 days. Short-term memory impairment was prevented by Brazil nuts in young rats (30 days). While the serum selenium concentration was reduced in the oHF group, the serum catalase concentration was reduced in all groups, without changes in lipid peroxidation or protein carbonylation. Brazil nut maternal diet supplementation prevented short- and long-term cognitive impairment in the offspring, which may be related to the selenium levels.


Subject(s)
Bertholletia , Cognitive Dysfunction , Selenium , Humans , Female , Male , Rats , Animals , Pregnancy , Rats, Wistar , Obesity , Dietary Supplements , Cognitive Dysfunction/etiology , Cognitive Dysfunction/prevention & control , Diet, High-Fat/adverse effects
12.
Acta amaz ; 53(1): 9-19, 2023. graf, tab
Article in English | LILACS, VETINDEX | ID: biblio-1414152

ABSTRACT

The most severe drought of this century in the Amazon rainforest, which was caused by El Niño, occurred from 2015 to 2016. With a focus on the ecophysiology of the regrowth of the Brazil nut tree, Bertholletia excelsa, it was investigated how the progression of the drought of 2015-2016 affected the physiological traits of the coppice regrowth of B. excelsa. The experiment was carried out in a ten-year-old plantation of Brazil nut trees, which had been subjected to thinning and coppice regrowth two years earlier. In the sprouts grown on the stumps of cut trees, the following treatments were applied: (T1) thinning to one sprout per stump; (T2) thinning to two sprouts per stump, and (T3) maintenance of three sprouts per stump. Thinning treatments did not alter the growth and ecophysiological traits of the Brazil nut tree sprouts, though the phosphorus content of the leaves was higher in T1. However, the progression of the drought in 2015-2016 negatively affected the growth (height) and gas exchange of sprouts of all treatments. In addition, an increase of around 37% was observed in the intrinsic wateruse efficiency. Concerning photochemical performance, no alterations were observed. Therefore, drought stress promoted a negative effect on sprout growth and affected traits related to the photosynthesis of the B. excelsa sprouts independently of the number of sprouts per stump.(AU)


A seca mais severa deste século na floresta amazônica, causada por El Niño, ocorreu de 2015 a 2016. Com foco na ecofisiologia da rebrota da castanheira da Amazônia, foi investigado como a progressão da seca de 2015-2016 afetou as características fisiológicas das rebrotas de uma talhadia de B. excelsa. O experimento foi realizado em uma plantação de castanheiras com dez anos, a qual havia sido submetida a um desbaste e rebrota de talhadia dois anos antes. Nas rebrotas crescidas sobre os tocos das árvores cortadas foram aplicados os seguintes tratamentos: (T1) desbrota para manter um broto por cepa; (T2) desbrota para manter dois brotos por cepa; e (T3) manutenção de três brotos por cepa. Os tratamentos de desbrota não alteraram o crescimento e as características ecofisiológicas dos brotos da castanheira, exceto para o teor foliar de fósforo, que foi maior em T1. Porém, a progressão da seca em 2015-2016 afetou negativamente o crescimento em altura e as trocas gasosas dos brotos de todos os tratamentos. Além disso, foi observado um aumento de cerca de 37% na eficiência intrínseca do uso da água. Quanto ao desempenho fotoquímico, não foram observadas alterações. Portanto, o estresse hídrico promoveu efeito negativo no crescimento da brotação e afetou características relacionadas à fotossíntese das brotações de B. excelsa, independentemente do número de brotações por cepa.(AU)


Subject(s)
Plant Structures/growth & development , Bertholletia/growth & development , Bertholletia/physiology , Brazil , El Nino-Southern Oscillation/adverse effects
13.
Demetra (Rio J.) ; 18: 73690, 2023. ^etab
Article in English, Portuguese | LILACS-Express | LILACS | ID: biblio-1532674

ABSTRACT

Introdução: A disbiose intestinal é uma característica comum na síndrome cardiorrenal e está associada ao aumento de toxinas urêmicas, como o N-óxido de trimetilamina (TMAO), que estão envolvidas com a inflamação e mortalidade cardiovascular. A castanha-do-Brasil (semente típica brasileira) possui propriedades anti-inflamatórias e antioxidantes, mas não há evidências dos seus efeitos na modulação da microbiota intestinal e redução de toxinas urêmicas. Objetivo: Avaliar o impacto do consumo de castanha-do-Brasil nos níveis de TMAO e marcadores de inflamação em um paciente com síndrome cardiorrenal. Métodos: Um paciente com doença arterial coronariana (66 anos e IMC, 26 kg/m2), estágio 3 da DRC (TFGe 36 mL/min), recebeu uma castanha-do-Brasil por dia durante três meses. Resultados: Os níveis plasmáticos de TMAO e a expressão de mRNA de NF-κB foram reduzidos e a atividade da glutationa peroxidase (GPx) aumentou após esta intervenção. Conclusão: A prescrição de castanha-do-Brasil pode ser uma estratégia promissora para mitigar as complicações relacionadas à síndrome cardiorrenal. Este caso apoia o conceito de "alimento como remédio" visando o fenótipo urêmico na síndrome cardiorrenal.


Introduction: Gut dysbiosis is a common feature in cardiorenal syndrome, and it is linked to increased uremic toxins, like trimethylamine-n-oxide (TMAO), which are involved with inflammation and cardiovascular mortality. Brazil nut (typical Brazilian seed) has anti-inflammatory and antioxidant properties, but there is no evidence of the effects of gut microbiota modulation and reduction of uremic toxins. Objective: To assess the impact of Brazil nut consumption on TMAO levels and inflammation markers in a patient with cardiorenal syndrome. Methods: Acoronary artery disease patient(66 years and BMI, 26 kg/m2),stage-3 of CKD (eGFR 36 mL/min), receivedone Brazil nut per day for three months. Results: TMAO plasma levels and NF-κB mRNA expression were reduced, and glutathione peroxidase (GPx) activity increased after this intervention. Conclusion: Brazil nut prescription may be a promising strategy to mitigate complications related tothe cardiorenal syndrome. This case supports the concept of "Food as medicine" targeting the uremic phenotype in cardiorenal syndrome.

14.
Materials (Basel) ; 15(20)2022 Oct 20.
Article in English | MEDLINE | ID: mdl-36295391

ABSTRACT

The regularities of the effect of a complex stress state on the strength of an AlMg5/epoxy adhesive joint are experimentally studied at -50 and +23 °C in tension+shear and compression+shear tests with different normal-to-shear stress ratios. The tests use modified Arcan specimens and Brazil-nut-sandwich specimens, with the lateral faces of the adhesive layer having a shape of a mushroom-like "ridge" aimed at reducing stress concentration at the specimen edges. An original computational model of a selected microvolume including the interface together with the adjacent substrate and adhesive layers is used to process the experimental results. The attainment of the threshold value of strain energy density in the selected microvolume, W*, is used as the failure criterion. The effect of the hardener composition, the testing temperature, and the value of the phase angle ß determining the proportion of normal and shear stresses at the adhesive interface on the threshold value W* is detected. W*(ß) diagrams (fracture loci) are plotted and analytically described logarithmic functions. They can be used to make strength calculations for adhesive joints in structures and metal-polymer composites.

15.
Nutrients ; 14(15)2022 Aug 05.
Article in English | MEDLINE | ID: mdl-35956381

ABSTRACT

Elevated levels of oxidative stress could cause and aggravate Alzheimer's disease (AD). Selenium (Se) is a trace element with antioxidant and anti-inflammatory activity with neuroprotective effects. To evaluate the effects of Se supplementation in patients with AD or mild cognitive impairment (MCI) through a systematic review and meta-analysis, data were searched and collected from four electronic databases, including clinical trial studies published until December 2020, following the PRISMA guidelines. Statistical analysis was performed by RevMan, and the risk of bias was assessed using the Rob 2 tool. A total of 1350 scientific papers were collected, and following evaluation 11 papers were included in the systematic review and 6 of these were used in the meta-analysis. Studies that evaluated only Se supplementation observed an improvement in Se levels, glutathione peroxidase (GPX) activity, and in some cognitive tests in MCI patients; similarly, improvement in Se levels and mini-mental score was also observed in AD patients. Regarding supplementation of Se plus other nutrients, improvement in cognitive tests was observed in both AD and MCI patients. Therefore, Se supplementation is a good alternative for patients with AD and MCI for improving Se levels and GPX activity. More detailed studies are required to further evaluate the effects of Se on the cognitive deficit and oxidative stress associated with AD and MCI.


Subject(s)
Alzheimer Disease , Cognition Disorders , Cognitive Dysfunction , Selenium , Alzheimer Disease/drug therapy , Antioxidants/therapeutic use , Cognitive Dysfunction/drug therapy , Dietary Supplements , Humans
16.
Molecules ; 27(16)2022 Aug 15.
Article in English | MEDLINE | ID: mdl-36014427

ABSTRACT

This work developd nanomaterials formulated from annatto seed oily extract (ASE), myristic acid (tetradecanoic acid), and their fatty acid esters. The annatto seed oily extract was obtained using only soybean oil (ASE + SO) and Brazil nut oil (ASE + BNO). The UV/VIS analysis of the oily extracts showed three characteristic peaks of the bixin molecule at 430, 456 and 486 nm. The lipid nanoparticles obtained using myristic acid and ASE + BNO or only BNO showed better results than the oil soybean extract, i.e., the particle size was <200 nm, PDI value was in the range of 0.2−0.3, and had no visual physical instability as they kept stable for 28 days at 4 °C. Lipid nanoemulsions were also produced with esters of myristic acid and ASE + BNO. These fatty acid esters significantly influenced the particle size of nanoemulsions. For instance, methyl tetradecanoate led to the smallest particle size nanoemulsions (124 nm), homogeneous size distribution, and high physical stability under 4 and 32 °C for 28 days. This work demonstrates that the chemical composition of vegetable oils and myristic acid esters, the storage temperature, the chain length of fatty acid esters (FAE), and their use as co-lipids improve the physical stability of lipid nanoemulsions and nanoparticles from annatto seed oily extract.


Subject(s)
Bixaceae , Carotenoids , Plant Extracts , Seeds , Fatty Acids , Liposomes , Myristic Acid , Nanoparticles , Plant Extracts/chemistry , Plant Extracts/pharmacology , Seeds/chemistry
17.
J Food Biochem ; 46(10): e14294, 2022 10.
Article in English | MEDLINE | ID: mdl-35762459

ABSTRACT

Oxidative stress, adipose tissue, and bone compartments can be disturbed in chronic diseases. Non-pharmacological strategies, such as Brazil nuts (BNs), can improve these parameters. This study evaluated the effects of BN supplementation at different concentrations on body composition, lipid profile, and peroxidation in healthy rats. Male Wistar rats were divided into three groups: control (CT), Brazil nut 5% (BN5), and Brazil nut 10% (BN10) groups. Body composition, brown adipose tissue (BAT), plasma lipid peroxidation, and lipid profile were evaluated in the three groups. The BN5 group showed an improvement in all bone parameters compared with that of the CT group (p  < .0001). The BN5 and BN10 groups showed reduced plasma lipid peroxidation compared with that of the CT group (p = .0009), whereas the BN10 group presented lower BAT lipid peroxidation than that of the other groups (p = .01). High-density lipoprotein-cholesterol (HDL-c) levels were higher in the BN5 group than in the CT group (p = .01). Conclusively, the use of BNs in a controlled manner promoted improvement in bone parameters, HDL-c levels, and lipid peroxidation in healthy rats. PRACTICAL APPLICATIONS: Nuts has been included in the diet because of their versatility, acceptance, and easy access. Among them, Brazil nut (BN) is considered one of the major known food sources of selenium as well as a source of fibers, unsaturated fatty acids, and phenolic compounds. Studies have shown that BN supplementation is effective in reducing oxidative stress, inflammation, lipid peroxidation, and selenium deficiency when used as a non-pharmacological strategy in experimental models of chronic diseases and in clinical trials. The present study showed that controlled administration of BN improved bone parameters, high-density lipoprotein-cholesterol levels, and lipid peroxidation in healthy rats. Therefore, BN is a promising non-pharmacological agent for the prevention of the onset of chronic non-communicable diseases.


Subject(s)
Bertholletia , Selenium , Animals , Male , Rats , Body Composition , Cholesterol , Diet , Dietary Supplements , Fatty Acids, Unsaturated , Lipid Peroxidation , Lipids , Lipoproteins, HDL , Rats, Wistar
18.
J Food Biochem ; 46(8): e14201, 2022 08.
Article in English | MEDLINE | ID: mdl-35467017

ABSTRACT

The purposes of this study were to assess the effect of Brazil nut supplementation on trimethylamine N-oxide (TMAO) levels and glutathione peroxidase (GPx) activity in patients with coronary artery disease (CAD). Patients with CAD were randomly assigned to two groups, Brazil nut group (23 patients, 48% male, 62.7 ± 6.8 years, 29.4 ± 5.8 kg/m2 ), which received one Brazil nut per day for 3 months, and the control group (14 patients, 43% male, 63.7 ± 8.7 years, 28.4 ± 4.2 kg/m2 ) who did not receive any supplementation. After 3 months, TMAO levels and their precursors did not change in either group. Although not significant, GPx activity increased by 41% in the Brazil nut group. TMAO levels were negatively associated with total fiber intake (r = -0.385 and p = .02). A 3-month Brazil nut supplementation did not change TMAO levels and GPx activity in CAD patients. PRACTICAL APPLICATIONS: Trimethylamine N-oxide (TMAO) has been associated with oxidative stress and cardiovascular disease risk. Thus, the increase in antioxidants enzymes production could be a promising strategy to reduce TMAO-mediated oxidative stress. In this context, nutritional strategies are well-known as activators of cellular antioxidant responses. As Brazil nuts have a known role in reducing oxidative stress by increasing glutathione peroxidase (GPx) activity (a selenium-dependent antioxidant enzyme), this study hypothesized that Brazil nuts could be a strategy that, via antioxidant capacity, would reduce TMAO plasma levels. Although no changes in TMAO levels and GPx activity can be observed in this study, it is believed that other results can be obtained depending on the dosage used. Thus, this study can open new paths and direct other studies with different doses and treatment times to evaluate the effects of Brazil Nuts on TMAO levels.


Subject(s)
Bertholletia , Coronary Artery Disease , Antioxidants , Coronary Artery Disease/drug therapy , Dietary Supplements , Female , Glutathione Peroxidase , Humans , Male , Methylamines , Oxides
19.
Br J Nutr ; : 1-38, 2022 Feb 23.
Article in English | MEDLINE | ID: mdl-35193718

ABSTRACT

Several mechanisms have been proposed for the beneficial effect of nuts on health. However, Brazil and cashew nuts remain the least studied. We aim to evaluate the effect of these nuts within an energy-restricted diet on body weight, body composition, cardiometabolic markers, and endothelial function in cardiometabolic risk women. Brazilian nuts study is a randomized controlled parallel 8-week dietary intervention trial. Forty women were randomly allocated to 1) Control group: Energy-restricted diet without nuts, n= 19 or, 2) Brazil and cashew nuts group (BN-Group): Energy-restricted diet containing daily 45 g of nuts (15 g of Brazil nuts + 30g of cashew nuts), n= 21. At the beginning and final intervention, anthropometry, body composition, and blood pressure were measured. Fasting blood sampling was obtained to evaluate lipid profile, glucose homeostasis, and endothelial function markers. After 8-week, plasma selenium concentration increased in BN-group (∆ = + 31.5 ± 7.8 µg/L; p= 0.001). Brazil and cashew nuts intake reduced total body fat (-1.3 ± 0.4 %) parallel to improvement of lean mass percentage in BN-group compared to the control. Besides, the soluble adhesion molecule VCAM-1 decreased (24.03 ± 15.7 pg/mL vs. -22.2 ± 10.3 pg/mL; p= 0.019) after Brazil and cashew nuts intake compared to the control. However, lipid and glucose profile markers, apolipoproteins, and blood pressure remained unchanged after the intervention. Thus, the addition of Brazil and cashew nuts to an energy-restricted diet can be a healthy strategy to improve body composition, selenium status, and endothelial inflammation in cardiometabolic risk women.

20.
Drug Chem Toxicol ; 45(3): 1066-1072, 2022 May.
Article in English | MEDLINE | ID: mdl-32811197

ABSTRACT

The Brazil nut (Bertholletia excelsa, H.B.K.) originating from the Amazon region is one of the richest known sources of selenium (Se), a micronutrient that is essential and required for optimal physiological functioning. This mineral presents several health benefits, including improvement of the redox cellular status and maintenance of genomic stability. Knowing that type 2 diabetes mellitus (T2D) is strongly linked to oxidative stress and consequently DNA damage, the aim of this study was to assess the ex vivo antioxidative effects of Se through Brazil nut consumption and its potential in preventing oxidative DNA damage induced by H2O2. In order to accomplish this, the Comet assay (single-cell gel electrophoresis) was used to measure DNA damage in peripheral blood cells harvested before and after supplementation with Brazil nut. Comet assay was also applied ex vivo to measure the potential of Se to prevent oxidative damage to DNA induced by H2O2 in blood of type 2 diabetes patients collected before and after six months of supplementation with Brazil nut. We found that supplementation with Brazil nuts significantly increased serum Se levels. Furthermore, we observed a significant increase in fasting blood glucose after six months of consuming Brazil nuts; however, no significant effect was observed on the levels of glycated hemoglobin. Finally, we noticed that the cells were more resistant to H2O2-induced DNA damage after six months of supplementation with Brazil nut. Thus, consumption of Brazil nuts could decrease oxidative DNA damage in T2D patients, probably through the antioxidative effects of Se.


Subject(s)
Bertholletia , Diabetes Mellitus, Type 2 , Selenium , Humans , Hydrogen Peroxide/pharmacology , Oxidative Stress , Selenium/pharmacology
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