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The coconut tree is a crop widely distributed in more than 90 countries worldwide. It has a high economic value derived from the large number of products obtained from the plant, with fast-growing global markets for some of them. Unfortunately, coconut production is decreasing mainly due to the old age of the plants and devastating pests and diseases, such as phytoplasma disease lethal yellowing (LY). Massive replanting is required with phytoplasma-resistant and high-yielding selected coconut plants to keep up with the market demand for fruit. For this purpose, an efficient micropropagation technology via somatic embryogenesis has been established at CICY, yielding fully developed vitro-plants grown within an in vitro environment. Hence, the last stage of the micropropagation process is the acclimatization of the vitro-plants, which are gradually adapted to live in external conditions outside the glass container and the growth room. A protocol has been developed at CICY to acclimate the coconut vitro-plants, and close to 80% survival can be obtained. This protocol is described here.

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This work aimed to define strategies to increase the bioproduction of 6 pentyl-α-pyrone (bioaroma). As first strategy, fermentations were carried out in the solid state, with agro-industrial residues: Mauritia flexuosa Liliopsida. and Manihot esculenta Crantz in isolation, conducting them with different nutrient solutions having Trichoderma harzianum as a fermenting fungus. Physicochemical characterizations, centesimal composition, lignocellulosic and mineral content and antimicrobial activity were required. Fermentations were conducted under different humidification conditions (water, nutrient solution without additives and nutrient solutions with glucose or sucrose) for 9 days. Bioaroma was quantified by gas chromatography, assisted by solid-phase microextraction. The results showed the low production of this compound in fermentations conducted with sweet cassava (around 6 ppm (w/w)). The low bioproduction with sweet cassava residues can probably be related to its starch-rich composition, homogeneous substrate, and low concentration of nutrients. Already using buriti, the absence of aroma production was detected. Probably the presence of silicon and high lignin content in buriti minimized the fungal activity, making it difficult to obtain the aroma of interest. Given the characteristics presented by the waste, a new strategy was chosen: mixing waste in a 1:1 ratio. This fermentation resulted in the production of 156.24 ppm (w/w) of aroma using the nutrient solution added with glucose. This combination, therefore, promoted more favorable environment for the process, possibly due to the presence of fermentable sugars from sweet cassava and fatty acids from the buriti peel, thus proving the possibility of an increase of around 2500% in the bioproduction of coconut aroma.

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Introduction: The coconut tree crop (Cocos nucifera L.) provides vital resources for millions of people worldwide. Coconut germplasm is largely classified into 'Tall' (Typica) and 'Dwarf' (Nana) types. While Tall coconuts are outcrossing, stress tolerant, and late flowering, Dwarf coconuts are inbred and flower early with a high rate of bunch emission. Precocity determines the earlier production of a plantation and facilitates management and harvest. Methods: A unique outbred F2 population was used, generated by intercrossing F1 hybrids between Brazilian Green Dwarf from Jiqui (BGDJ) and West African Tall (WAT) cultivars. Single-nucleotide polymorphism (SNP) markers fixed for alternative alleles in the two varieties, segregating in an F2 configuration, were used to build a high-density linkage map with ~3,000 SNPs, anchored to the existing chromosome-level genome assemblies, and a quantitative trait locus (QTL) mapping analysis was carried out. Results: The linkage map established the chromosome numbering correspondence between the two reference genome versions and the relationship between recombination rate, physical distance, and gene density in the coconut genomes. Leveraging the strong segregation for precocity inherited from the Dwarf cultivar in the F2, a major effect QTL with incomplete dominance was mapped for flowering time. FLOWERING LOCUS T (FT) gene homologs of coconut previously described as putatively involved in flowering time by alternative splice variant analysis were colocalized within a ~200-kb window of the major effect QTL [logarithm of the odds (LOD) = 11.86]. Discussion: Our work provides strong phenotype-based evidence for the role of the FT locus as the putative underlying functional variant for the flowering time difference between Dwarf and Tall coconuts. Major effect QTLs were also detected for developmental traits of the palm, plausibly suggesting pleiotropism of the FT locus for other precocity traits. Haplotypes of the two SNPs flanking the flowering time QTL inherited from the Dwarf parent BGDJ caused a reduction in the time to flower of approximately 400 days. These SNPs could be used for high-throughput marker-assisted selection of early-flowering and higher-productivity recombinant lines, providing innovative genetic material to the coconut industry.

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The objective was to characterize the pastures by grazing cycle, as well as to evaluate the performance of buffaloes in intensive rotational grazing in a silvopastoral system in the eastern Amazon supplemented with agro-industry co-products in order to characterize the grazing cycles, the composition of the fractions, and the carcass yield. Fifteen non-castrated, crossbred water buffaloes (Murrah × Mediterranean) were used. All animals used in the study were clinically healthy and weighed approximately 458 kg. The animals were grazed in a single group, and supplementation (1% of live weight-LW/day) was divided into three treatments: control (control-conventional ingredients); Cocos nucifera coconut cake (Cocos nucifera) (coconut cake-70%); and palm kernel cake (Guinean elaeis) (palm kernel cake-70% palm kernel cake). The chemical composition of the forage is different in each part of the plant, with higher protein values in the leaves (11.40%) and higher acid detergent fiber (ADF) values in the stems (50.03%). Among the ingredients of the supplement, corn has the highest percentage of indigestible protein (35.57%), most of the protein in palm kernel cake is B3 (49.11%), and in Coco, B2 (51.52%). Mombasa grass has a higher percentage of B3 and B2 proteins; the indigestible fraction is lower in the leaves (17.16%). The leaf/stem ratio also varied between grazing cycles, being better in the second cycle (2.11%) and with an overall average of 1.71. Supplement consumption varied between cycles and was higher in the control treatment, with an overall mean of 4.74. There was no difference in daily weight gain and carcass yield, with an average of 1 kg/day and 49.23%, respectively. Therefore, it can be concluded that including supplements based on by-products from the coconut and palm oil agro-industries promotes performance and carcass yields compatible with conventional supplements. Their use reduces production costs, optimizes the utilization of forage mass, enhances the sustainability of the production chain, and, therefore, is recommended.

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Introduction: Aluminum Phosphide (AlP) poisoning constituted the most common cause of poisoning death in some low- and middle-income countries (LMICs). This study aimed to evaluate the safety and efficacy of oil-based gastric lavage (GL) compared with standard therapy for the treatment of AlP poisoning. Materials and methods. This systematic review complied with "Preferred Reporting Items for Systematic Reviews and Meta-Analyses" (PRISMA) Protocols. A comprehensive search was carried out, identifying randomized controlled trials (RCTs), including anyone presenting within 6 h of exposure to AlP, and the administration of GL with oils, including liquid paraffin or coconut oil. Results: We identified 7 RCTs. The evidence from 4 RCTs indicates that GL with paraffin oil is an effective treatment for acute AlP poisoning, decreasing the mortality rate (RR = 0.62; 95% CI = 0.48 to 0.81; participants = 226; I 2 = 10%; low-quality evidence). We estimate the Number Needed to Treat of 4. Likewise, this intervention reduces the need for intubation and mechanical ventilation (RR = 0.62; 95% CI = 0.40 to 0.79; I2 = 0%; low-quality evidence). Regarding GL with coconut oil, the evidence from 4 RCTs, indicates a slight reduction in mortality (RR = 0.82; 95% CI = 0.69 to 0.98; participants = 112; I2 = 0%; very low-quality evidence). Conclusions: Limited evidence suggests that GL with paraffin oil is effective in reducing the mortality rate. Likewise, limited evidence showed in favor of paraffin oil concerning the need for intubation and mechanical ventilation. Very limited evidence suggests that GL with coconut oil could reduce mortality. Both interventions would have a benign safety profile.

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The use of natural fibers in cementitious composites has been gaining prominence in engineering. The natural lignocellulosic fibers (NLFs) used in these composites have advantages such as reduced density, reduced fragmentation and concrete cracking, thus improving flexural performance and durability. Coconut-fiber is one of those natural fibers and its use presents technical, ecological, social and economic benefits, as it is improperly disposed of, representing a large waste of natural resources, in addition to causing environmental pollution.. Thus, composites reinforced with natural fibers are promising materials for the construction industry, as in addition to meeting the sustainability of buildings, there will also be a reduction in urban solid waste generated and gains for structures with the use of environmentally friendly materials that meet to active efforts and with greater durability. This work aims to evaluate the tensile behavior of green coconut-fibers subjected to different drying temperatures through chemical, thermal (TG/DSC), morphological, visual and mechanical analysis. Drying temperatures of 70 °C, 100 °C and 130 °C were analyzed and the results indicated that the drying temperature at 70 °C was satisfactory, providing fiber-reinforced composites with good tensile strength, combined with good ductility.

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The red palm mite Raoiella indica Hirst, 1924 (Acari: Tenuipalpidae) is an important pest of the coconut palm Cocos nucifera L. (Arecaceae) and has caused problems in coconut production worldwide. Research has been carried out aiming at controlling the mite through chemical, biological, alternative, and host plant resistance methods. Identifying coconut palm cultivars resistant to R. indica is important to reduce the problems caused to plantations. Therefore, the objective of this work was to evaluate the performance of R. indica in six dwarf coconut palm cultivars, to identify sources of resistance. The cultivars of the sub-varieties green, red, and yellow evaluated were Brazilian Green Dwarf-Jiqui (BGDJ), Brazilian Red Dwarf-Gramame (BRDG), Cameroon Red Dwarf (CRD), Malayan Red Dwarf (MRD), Brazilian Yellow Dwarf-Gramame (BYDG), and Malayan Yellow Dwarf (MYD). Confinement and free choice tests of R. indica on the cultivars were performed, in which biological parameters and preference were evaluated. Mite performance was different in the cultivars evaluated. In the confinement bioassay, R. indica had the worst performance in the cultivar BGDJ, the best performance in CRD, MRD, and BRDG, and intermediate performance in BYDG and MYD. In the free choice test, the cultivars MRD and MYD were preferred in relation to BGDJ, and CRD was less preferred in relation to BGDJ. Therefore, we considered that the cultivar BGDJ is the most resistant to R. indica, by antibiosis and antixenosis; CRD has resistance by antixenosis; and MRD, BRDG, BYDG, and MYD are susceptible.

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Abstract The study was designed to investigate the effect of Coconut Oil on the levels of some liver and hematological parameters in carbon tetrachloride intoxicated rabbits. Also the antioxidant capacity of Coconut Oil for various concentrations was assessed on the basis of percent scavenging of (DPPH) free radical. Experimental animals were divided into five groups, eight rabbits in each group. These were: group A (Normal control), group B (Toxic control), group C (Standard control), group D (Treated with Coconut Oil 50 mL/kg body weight after CCl4 intoxication), group E (Treated with Coconut Oil 200 mL/kg body weight after CCl4 intoxication). The effects observed were compared with a standard hepatoprotective drug silymarine (50 mL/kg body weight). The Coconut Oil (200 mL/kg body weight) significantly (P 0.05) reduced the elevated serum levels of alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP) when compared to a toxic control rabbits. The results of extract treated rabbits were similar to silymarine administered rabbits group. Treatment with Coconut Oil root and silymarine caused no significant changes in RBC, Platelets, (Hb), (MCH) concentration and (HCT) values. However, significant (P 0.05) increase was observed in the total WBC count. The present study suggested that Coconut Oil can be used as an herbal alternative (need further exploration i.e to detect its bioactive compound and its efficacy) for hepatoprotective activity.

Resumo O estudo foi desenhado para investigar o efeito do óleo de coco nos níveis de alguns parâmetros hepáticos e hematológicos em coelhos intoxicados com tetracloreto de carbono. Também a capacidade antioxidante do óleo de coco para várias concentrações foi avaliada com base na porcentagem de eliminação de radicais livres (DPPH). Os animais experimentais foram divididos em cinco grupos, oito coelhos em cada grupo. Estes foram: grupo A (controle normal), grupo B (controle tóxico), grupo C (controle padrão), grupo D (tratado com óleo de coco 50 mL/kg de peso corporal após intoxicação por CCl4), grupo E (tratado com óleo de coco 200 mL/kg de peso corporal após intoxicação por CCl4). Os efeitos observados foram comparados com um fármaco hepatoprotetor padrão silimarina (50 mL/kg de peso corporal). O óleo de coco (200 mL/kg de peso corporal) reduziu significativamente (P 0,05) os níveis séricos elevados de alanina transaminase (ALT), aspartato transaminase (AST) e fosfatase alcalina (ALP), quando comparado a um coelho controle tóxico. Os resultados dos coelhos tratados com extrato foram semelhantes aos do grupo de coelhos administrados com silimarina. O tratamento com raiz de óleo de coco e silimarina não causou alterações significativas nos valores de RBC, Plaquetas, (Hb), (MCH) e (HCT). No entanto, observou-se aumento significativo (P 0,05) na contagem total de leucócitos. O presente estudo sugeriu que o óleo de coco pode ser usado como uma alternativa fitoterápica (precisa de mais exploração, ou seja, para detectar seu composto bioativo e sua eficácia) para atividade hepatoprotetora.

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The study was designed to investigate the effect of Coconut Oil on the levels of some liver and hematological parameters in carbon tetrachloride intoxicated rabbits. Also the antioxidant capacity of Coconut Oil for various concentrations was assessed on the basis of percent scavenging of (DPPH) free radical. Experimental animals were divided into five groups, eight rabbits in each group. These were: group A (Normal control), group B (Toxic control), group C (Standard control), group D (Treated with Coconut Oil 50 mL/kg body weight after CCl4 intoxication), group E (Treated with Coconut Oil 200 mL/kg body weight after CCl4 intoxication). The effects observed were compared with a standard hepatoprotective drug silymarine (50 mL/kg body weight). The Coconut Oil (200 mL/kg body weight) significantly (P<0.05) reduced the elevated serum levels of alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP) when compared to a toxic control rabbits. The results of extract treated rabbits were similar to silymarine administered rabbits group. Treatment with Coconut Oil root and silymarine caused no significant changes in RBC, Platelets, (Hb), (MCH) concentration and (HCT) values. However, significant (P<0.05) increase was observed in the total WBC count. The present study suggested that Coconut Oil can be used as an herbal alternative (need further exploration i.e to detect its bioactive compound and its efficacy) for hepatoprotective activit.

O estudo foi desenhado para investigar o efeito do óleo de coco nos níveis de alguns parâmetros hepáticos e hematológicos em coelhos intoxicados com tetracloreto de carbono. Também a capacidade antioxidante do óleo de coco para várias concentrações foi avaliada com base na porcentagem de eliminação de radicais livres (DPPH). Os animais experimentais foram divididos em cinco grupos, oito coelhos em cada grupo. Estes foram: grupo A (controle normal), grupo B (controle tóxico), grupo C (controle padrão), grupo D (tratado com óleo de coco 50 mL/kg de peso corporal após intoxicação por CCl4), grupo E (tratado com óleo de coco 200 mL/kg de peso corporal após intoxicação por CCl4). Os efeitos observados foram comparados com um fármaco hepatoprotetor padrão silimarina (50 mL/kg de peso corporal). O óleo de coco (200 mL/kg de peso corporal) reduziu significativamente (P<0,05) os níveis séricos elevados de alanina transaminase (ALT), aspartato transaminase (AST) e fosfatase alcalina (ALP), quando comparado a um coelho controle tóxico. Os resultados dos coelhos tratados com extrato foram semelhantes aos do grupo de coelhos administrados com silimarina. O tratamento com raiz de óleo de coco e silimarina não causou alterações significativas nos valores de RBC, Plaquetas, (Hb), (MCH) e (HCT). No entanto, observou-se aumento significativo (P<0,05) na contagem total de leucócitos. O presente estudo sugeriu que o óleo de coco pode ser usado como uma alternativa fitoterápica (precisa de mais exploração, ou seja, para detectar seu composto bioativo e sua eficácia) para atividade hepatoprotetora.

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The aim of this work was to evaluate the adsorptive performance of the phosphorylated coconut fiber lignin (PCFL) obtained through an innovative biorefinery process for removing methylene blue (MB). PCFL was obtained using coconut fiber mixed with 85 % wt. H3PO4 at 70 °C for 1 h. Milled wood lignin (MWL) and PCFL were characterized by FTIR, CP-MAS 31P NMR, phosphorous and hydroxyl contents, pHPZC, and BET analyses. The batch adsorption tests evaluated the effects of the biosorbent (0.25 - 4 g L-1) and adsorbate dosages (2.5 - 7.5 mg L-1), contact time (0 - 60 min), pH (4 - 8), ionic strength (0.001 - 0.1 mol L-1) and temperature (298.15 - 318.15 K) on MB adsorption. Kinetic, equilibrium, and thermodynamic modeling were used. The phosphorous content on PCFL was 2.5 times higher than that of MWL. PCFL presented an enhanced adsorptive performance for removing MB, which was spontaneous (ΔG0 < 0), endothermic (ΔH0 > 0), with affinity between the biosorbent and adsorbate (ΔS0 > 0), and driven by physisorption (Ea > 40 kJ mol-1). The adsorptive performance of PCFL was enhanced due to the grafting of new active sites by using an innovative biorefinery process, showing its potential to be used for textile effluent remediation.

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The main goal of this work was to evaluate the therapeutic potential of green superparamagnetic iron oxide nanoparticles (SPIONs) produced with coconut water for treating cutaneous leishmaniasis caused by Leishmania amazonensis. Optical and electron microscopy techniques were used to evaluate the effects on cell proliferation, infectivity percentage, and ultrastructure. SPIONs were internalized by both parasite stages, randomly distributed in the cytosol and located mainly in membrane-bound compartments. The selectivity index for intracellular amastigotes was more than 240 times higher compared to current drugs used to treat the disease. The synthesized SPIONs showed promising activity against Leishmania and can be considered a strong candidate for a new therapeutic approach for treating leishmaniases.

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In agricultural countries, Agro-industrial residues are better treated with a circular production logic. This article analyzes the morphological, physical, mechanical, thermal, and chemical characteristics of the coconut fiber and endocarp in Portoviejo and Rocafuerte Cities, Ecuador, to establish a baseline of knowledge that can help to incorporate coconut residues into a matrix of a new material. Interviews were conducted to coconut producers in Portoviejo and Rocafuerte and a random sample of the residues was collected from these locations. Analyses were performed using the SEM, TGA and FRX tests. Concerning the fiber, it was observed a tubular morphology with concentric microfibrils, specific weight 0.69 g/cm3, tensile strength 228 MPa, modulus of elasticity 3.03 GPa, thermal behavior with important mass losses at 330 °C, in the calcinations to obtain oxides as SiO2, SO3, Al2O3, Fe2O3 at 600 °C and 650 °C. The endocarp has a morphology of superimposed and consolidated smooth layers, specific weight 1.29 g/cm3, loss of mass at 339 °C and in calcinations at 800 °C. This study can help to address solid vegetable waste managing challenges in coconut producing cities.

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Poultry meat allergy is rare and may present as primary or secondary, in the context of bird-egg syndrome. Chicken meat is responsible for most of the reactions. Cross-reactive allergens (parvalbumins, enolases, aldolases) between fish and chicken meat have been described. Coconut allergy is also rare. Coc n2 (7S globulin) and Coc n4 (11S globulin) have been implicated. We present a complex multiple food allergy case report where investigation into fish and chicken meat allergies as well as coconut allergy is carried out.

A alergia à carne de aves é rara e pode apresentar-se como primária ou secundária, no contexto da síndrome ovo-ave. A carne de frango é responsável pela maioria das reações. Foram descritos alergênios com reação cruzada (parvalbuminas, enolases, aldolases) entre peixe e carne de frango. A alergia ao coco também é rara. Coc n2 (globulina 7S) e Coc n4 (globulina 11S) foram implicados. Apresentamos um relato de caso complexo de alergia alimentar múltipla, onde é realizada investigação sobre alergia a peixe e carne de frango, bem como alergia ao coco.

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This study was aimed to assess the efficiency of coconut water extender with addition of soy lecithin and sucrose as nonpermeable cryoprotectants for canine semen vitrification, using a simple method that yields a high survival rate of spermatozoa for clinical use. Twelve ejaculates from 12 adult normozoospermic dogs were collected separately by digital manipulation and only the second semen fraction was used in this study. After evaluation of volume, concentration, viability, total and progressive motility, velocity parameters and morphology, semen was diluted with a coconut water extender (50% (v/v(volume per volume)) coconut water, 25% (v/v) distilled water and 25% (v/v) 5% anhydrous monosodium citrate solution) with addition of soy lecithin and fructose at 1% and 0.25M sucrose until final concentration of 100x106 spermatozoa/ml. After equilibration at 5ºC for 60 minutes, semen was vitrified by "direct dropping method" into liquid nitrogen in spheres with a volume of 30 µl. After a week of storage the spheres were devitrified as three of them were dropped into 0.5 mL of CaniPlus AI medium (Minitüb, Germany), which was previously warmed in a water bath at 42ºC for 2 minutes and evaluated about the above mentioned parameters. It was found that vitrification resulted in a lower percentage of viable sperms, normal morphology, total and progressive motilities (p<0.05), but most of velocity parameters (VCL, VSL, VAP, LIN, ALH and BCF) did not differ (p>0.05) compared to fresh semen samples. In conclusion, our results demonstrate that vitrification with coconut water extender with addition of 1% soy lecithin and 0.25M sucrose as cryoprotectants, has an excellent potential for routine canine sperm cryopreservation.

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Cocos nucifera L. is a crop grown in the humid tropics. It is grouped into two classes of varieties: dwarf and tall; regardless of the variety, the endosperm of the coconut accumulates carbohydrates in the early stages of maturation and fatty acids in the later stages, although the biochemical factors that determine such behavior remain unknown. We used tandem mass tagging with synchronous precursor selection (TMT-SPS-MS3) to analyze the proteomes of solid endosperms from Yucatan green dwarf (YGD) and Mexican pacific tall (MPT) coconut cultivars. The analysis was conducted at immature, intermediate, and mature development stages to better understand the regulation of carbohydrate and lipid metabolisms. Proteomic analyses showed 244 proteins in YGD and 347 in MPT; from these, 155 proteins were shared between both cultivars. Furthermore, the proteomes related to glycolysis, photosynthesis, and gluconeogenesis, and those associated with the biosynthesis and elongation of fatty acids, were up-accumulated in the solid endosperm of MPT, while in YGD, they were down-accumulated. These results support that carbohydrate and fatty acid metabolisms differ among the developmental stages of the solid endosperm and between the dwarf and tall cultivars. This is the first proteomics study comparing different stages of maturity in two contrasting coconut cultivars and may help in understanding the maturity process in other palms.

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Zinc phosphide is a rodenticide that is used in agricultural, urban and industrial environments in México. After ingestion, it reacts with hydrochloric acid, hydrolyzing into phosphine. It causes cellular hypoxia via mitochondrial toxicity, resulting in multiple organ dysfunction and death. There is no antidote or specific treatment for zinc phosphide toxicity. We present the case of a 45-year-old female who ingested zinc phosphide with suicidal intent. On arrival at the emergency department, she had multisystemic disorders. Supportive care, decontamination and antidotal therapy were initiated. Subsequently, she evolved to clinical improvement with a resolution of the biochemical abnormalities of tissue hypoperfusion. She was discharged on day 7 without complications. In this review, we provide updated therapeutic options and discuss their specific pathophysiological basis.

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Recent data from meta-analyses of randomized clinical trials (RCTs) suggest that dietary intake of coconut oil, rich in saturated fatty acids, does not result in cardiometabolic benefits, nor in improvements in anthropometric, lipid, glycemic, and subclinical inflammation parameters. Nevertheless, its consumption has surged in recent years all over the world, a phenomenon which can possibly be explained by an increasing belief among health professionals that this oil is as healthy as, or perhaps even healthier than, other oils, in addition to social network misinformation spread. The objective of this review is to present nutritional and epidemiological aspects related to coconut oil, its relationship with metabolic and cardiovascular health, as well as possible hypotheses to explain its high rate of consumption, in spite of the most recent data regarding its actual effects.

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The lignin valorization constitutes a chemical platform for several segments of chemical industry. The aim of this work was to evaluate the potential of acetosolv coconut fiber lignin (ACFL) as an additive to DGEBA, curing it using an aprotic IL ([BMIM][PF6]) and analyze the properties of the obtained thermosetting materials. ACFL was obtained by mixing coconut fiber with 90 % acetic acid and 2 % HCl at 110 °C during 1 h. ACFL was characterized by FTIR, TGA and 1H NMR. The formulations were fabricated by mixing DGEBA and ACFL at different concentrations (0-50 % wt.). The curing parameters and [BMIM][PF6] concentrations were optimized by DSC analyses. The cured ACFL-incorporated epoxy resins were characterized by gel content (GC), TGA, MCC and chemical resistance in different media. ACFL undergone a selective partial acetylation that favored its miscibility with DGEBA. High GC values were obtained at high curing temperatures and ACFL concentration. The crescent ACFL concentration did not affect the Tonset of the thermosetting materials significantly. ACFL has increased the resistance of DGEBA to combustion and different chemical media. ACFL has shown a great potential to be used as a bio-additive for enhancing the chemical, thermal and combustion properties of high-performance materials.

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This study proposes a novel test method and corresponding procedure to evaluate how coconut fibres affect crack propagation rates resulting from plastic shrinkage during the accelerated drying of concrete slabs. The experiment employed concrete plate specimens, which were used to simulate slab structural elements with a surface dimension notably greater than their thickness. These slabs were reinforced with coconut fibre with 0.5%, 0.75%, and 1% fibre content. A wind tunnel was designed to simulate two significant climate parameters (wind speed and air temperature), which could impact the cracking behaviour of surface elements. The proposed wind tunnel allowed air temperature to be controlled alongside wind speed while monitoring moisture loss and the cracking propagation process. During testing, a photographic recording method was used to evaluate cracking behaviour, with the total crack length serving as a parameter to assess the impact of fibre content on the crack propagation of slab surfaces. Additionally, crack depth was measured using ultrasound equipment. The results indicate that the proposed test method was appropriate for future research, allowing for the evaluation of the effect of natural fibres on the plastic shrinkage behaviour of surface elements under controlled environmental conditions. Based on initial studies and the results obtained through the proposed test method, concrete containing 0.75% fibre content exhibited significantly reduced crack propagation on slab surfaces, as well as a reduction in the crack depth caused by plastic shrinkage during the early age of the concrete.

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Engineering activities aim to satisfy the demands of society. Not only should the economic and technological aspects be considered, but also the socio-environmental impact. In this sense, the development of composites with the incorporation of waste has been highlighted, aiming not only for better and/or cheaper materials, but also optimizing the use of natural resources. To obtain better results using industrial agro waste, we need to treat this waste to incorporate engineered composites and obtain the optimal results for each application desired. The objective of this work is to compare the effect of processing coconut husk particulates on the mechanical and thermal behavior of epoxy matrix composites, since we will need a smooth composite in the near future to be applied by brushes and sprayers with a high quality surface finish. This processing was carried out in a ball mill for 24 h. The matrix was a Bisphenol A diglycidyl ether (DGEBA)/triethylenetetramine (TETA) epoxy system. The tests that were performed were resistance to impact and compression, as well as the linear expansion test. Through this work, it can be observed that the processing of coconut husk powder was beneficial, allowing not only positive improvements to the properties of the composite, but also a better workability and wettability of the particulates, which was attributed to the change in the average size and shape of particulates. That means that the composites with processed coconut husk powders have improved impact strength (46 up to 51%) and compressive strength (88 up to 334%), in comparison with unprocessed particles.