Effect of açai supplementation (Euterpe Oleracea Mart) associated with exercise in animals and human: a scoping review / Efeitos da suplementação com açaí (Euterpe Oleracea Mart) associada ao exercício físico em animais e humanos: revisão de escopo

ABSTRACT Objective This scoping review aimed to map evidence on açai supplementation combined with exercise in animal and/or human experimental studies. Methods The search considered six electronic databases and screening of relevant references. The selection process and data extraction were performed by two independent authors. The study characteristics, and AS (e.g., form, intervention time, amount ingested) and exercise (e.g., types, intensity, and duration) strategies were summarized, as well as their reported results. Results From an initial total of 342 studies identified; 11 (5 with animal and 6 with human models) were eligible. In animals, açai supplementation and exercise led to benefits in exercise tolerance and improvements in several hemodynamic parameters, as well as significant improvements in liver markers and glucose metabolism. In humans, açai supplementation indicated positive results in increasing exhaustion time to 90% of VO2max and increasing intensity at the anaerobic threshold. Conclusion We conclude that future research involving animals and humans should examine açai supplementation and exercise with (a) obesity models to test the effect of adiponectin on body composition with analysis of histological and histochemical parameters; (b) eccentric injury protocols with the incorporation of muscle quality variables to assess recovery; (c) chronic açai supplementation and strength training; (d) comparison of different forms of açai supplementation in exercise protocols.

RESUMO Objetivo Esta revisão de escopo teve como objetivo mapear evidências sobre a suplementação com açaí combinada com exercícios físicos em estudos experimentais em animais e / ou humanos. Métodos A busca considerou seis bases de dados eletrônicas além da triagem de referências relevantes. O processo de seleção e extração de dados foi realizado por dois autores independentes. As características do estudo, estratégias de suplementação de açaí (forma, tempo de intervenção, e quantidade ingerida) e exercícios (tipos, intensidade e duração), seus resultados foram resumidos. Resultados Um total de 342 estudos foram inicialmente alcançados e somente 11 foram elegíveis (5 com animais e 6 com humanos). Em animais, a suplementação de açaí e os exercícios indicaram benefícios na tolerância ao exercício e melhorias em vários parâmetros hemodinâmicos, bem como melhorias significativas nos marcadores hepáticos e no metabolismo da glicose. Em humanos, a suplementação de açaí indicou resultados positivos no aumento do tempo de exaustão para 90% do VO2máx e no aumento da intensidade correspondente ao limiar anaeróbio. Conclusão Concluiu-se que pesquisas futuras envolvendo animais e humanos devem examinar a suplementação de açaí e exercícios com (a) modelos de obesidade para testar o efeito da adiponectina na composição corporal por meio de parâmetros histológicos e histoquímicos (b) protocolos de dano muscular excêntrico com incorporação de variáveis de qualidade muscular para avaliação da recuperação; (c) suplementação crônica de açaí e treinamento de força; (d) comparação das diferentes formas de suplementação de açaí em protocolos de exercícios.

Morphostructural and histochemical dynamics of Euterpe precatoria (Arecaceae) germination.

The fruits of Euterpe precatoria, popularly known as açaí palm, have been commercially exploited for use in food and beverages because of their medicinal and energetic properties. However, despite the growing demand, little is known about the seeds germination, until now, its main form of propagation. In this context, we have characterized the structure of the zygotic embryo and described temporally the germination process of E. precatoria with emphasis on the morpho-anatomical and histochemical aspects. For this end, we have collected and analyzed zygotic embryo and seedlings samples before sowing and at different periods after sowing-2, 4, 6, 8, 10, 15, 20, 30, 40, 50, and 60 days. The embryo has an oblique embryonic axis and mainly protein reserves. Seed germination is classified as cryptocotyledonar, hypogeal, and adjacent ligular and we observed seedlings at 20 days after sowing (33.3%), although anatomical evidence of the beginning of the germination process have been observed at 15 days. The day-20 was histologically marked by the expansion of the ligule, beginning of second eophyll differentiation, and complete root protrusion. This stage was characterized by the total consumption of protein reserves and increased starch grains. The occurrence of 100% of root and ligula emission was verified at day-60, which characterizes a slow and heterogeneous process. The morphological marker of the E. precatoria germination is the exit of the proximal region (cotyledonary petiole) of the embryo from within the seed by the lifting of the operculum and the species has some peculiarities, such as the presence of high concentrations of phenolic compounds and idioblasts before and throughout the germination process, and starch grains located on the embryonic axis. We can verify that the consumption of protein reserves of the embryo is related to the energy supply necessary for root protrusion.

Proteome dynamics of the cotyledonary haustorium and endosperm in the course of germination of Euterpe oleracea seeds.

The role of the cotyledonary haustorium (CH) in the mobilization of nutrient reserves in the endosperm of species of the palm family Arecaceae is a moot question. To shed light on this matter, we present here an analysis of the quantitative proteome changes associated with four developmental stages of CH and three of endosperm during germination. Together, a total of 1965 proteins were identified, being 1538 in the CH and 960 in the endosperm. Both in the CH and endosperm proteomes, we observed an increase in the diversity of hydrolases as the CH and endosperm develops. Qualitative proteomics analysis of four CH developmental stages indicated that each stage is populated by a unique set of proteins and the quantitative analysis showed an increase in the relative abundance of hydrolases, particularly mannan degrading enzymes, as development progresses. These results add weight to the hypothesis that the CH in the seeds of E. oleraceaacts both as a conduit of carbon and nitrogen sources generated by the hydrolysis of the reserves in the endosperm and as a source of hydrolases that will contribute to the mobilization of these reserves.

Pollen Loads of Flower Visitors to Açaí Palm (Euterpe oleracea) and Implications for Management of Pollination Services.

Understanding the functional roles of different pollinator species is crucial to the development of sustainable farming practices in pollinator-dependent crops. However, this can be challenging for crop plants in tropical regions with hyper-diverse pollinator communities. Here, we assess pollen loads of different insect visitors to inflorescences of açaí palm (Euterpe oleracea), the most important native crop in the Amazon estuary region. Flower-visiting insects were collected from pistillate (female) inflorescences at eight sites, including four managed floodplain forests and four plantations. Pollinator Importance Value Index (PIVI) and Relative Importance (RI) scores were calculated for common visitor taxa (≥ 10 individuals) using sum visit frequencies and median pollen loads. Pollen load analyses revealed that over seventy insect taxa, including bees, flies, beetles, wasps and ants, were effective vectors of E. oleracea pollen. Native bees, including both solitary and eusocial taxa, were the most efficient pollen vectors, with median pollen loads at least eight times higher than those of the next best insect group (flies). Insect pollen loads were at their highest between 0800 and 1300 hours, and four insect taxa had RI scores > 0.05, including two meliponine bees belonging to the Trigona genus (Trigona branneri Cockerell and Trigona pallens Fabricius) and two halictid bee genera (Augochloropsis and Dialictus). Our results suggest that native bees play an important role in açaí pollination and should be the primary focus of pollinator management in açaí production systems.

Consumption of Euterpe edulis fruit by wildlife: implications for conservation and management of the Southern Brazilian Atlantic Forest.

This study aimed to measure the wildlife consumption of Euterpe edulis fruit and use this data to discuss management possibilities. To estimate infructescence fruit volume consumed, collectors were installed in fruit-bearing palms. To characterize consumption from the ground, samples were placed next to fruiting palms. To identify wildlife and their activities, camera traps were installed in infructescences and on the ground. The results suggested that there was a small fruit surplus (1.8 %), and this finding indicated the possibility of a harvest to reduce food for the wildlife. However, recurrent variations in the annual fruit production (21.4 %) were also noted, and suggested that wildlife could tolerate some fruit harvesting. Thus, a harvest could be restricted to fruit volume that exceeds the annual average (94 kg/ha/year). Turdus flavipes, a migratory bird, was the most active species in the dispersal of seeds; this finding indicates the need for broader conservation strategies. Wildlife composition also changed along with the fruiting, and this alteration suggests that dependence on the fruit is variable among different species. Seed germination and seedling mortality were high, results that indicate that local conditions may have a predominant effect on seed volume in natural regeneration density.

Coupling physiological analysis with proteomic profile to understand the photosynthetic responses of young Euterpe oleracea palms to drought.

This study examined whether drought sensitivity in açaí (Euterpe oleracea Mart.) is associated with reductions in photosynthesis and increasing oxidative stress in response to down-regulation of proteins related to photosynthetic reactions, photorespiration, and antioxidant system. Well-watered (Control) and drought-stressed plants were compared when leaf water potential in stressed plants reached around - 1.5 and - 3.0 MPa, representing moderate and severe drought. Drought caused 84 and 96% decreases in net photosynthetic rate (Pn) and stomatal conductance. Stress-mediated changes in maximum quantum efficiency of photosystem II (PSII) photochemistry were unobserved, but drought decreased photochemical quenching, actual quantum yield of PSII electron transport, and apparent electron transport rate (ETR). Moderate and severe drought induced, respectively, decreases and increases in non-photochemical quenching (NPQ) and 74 and 273% increases in ETR/Pn. Moderate drought down-regulated PSII protein D2, chlorophyll a-b binding protein 8, photosystem I reaction center subunit N, sedoheptulose-1,7-bisphosphatase, and transketolase; while severe drought down-regulated LHC II proteins, ferredoxin-NADP reductase, ATP synthase subunits ε and ß, and carbonic anhydrase isoform X2. The glutamate-glyoxylate aminotransferase 2 and glycine dehydrogenase were down-regulated upon moderate drought, while catalase 2 and glycine cleavage system H protein 3 were up-regulated. Severe drought up-regulated glycolate oxidase, glycine cleavage system H protein 3, and aminomethyl transferase, but most of photorespiration-related proteins were only found in control plants. Down-regulation of chaperones and antioxidant enzymes and increased lipid peroxidation in stressed plants were observed upon both stress severities. Therefore, the decreases in Pn and failure in preventing oxidative damages through adjustments in NPQ and photorespiration- and antioxidant-related proteins accounted for drought sensitivity in açaí.

The risks of introduction of the Amazonian palm Euterpe oleracea in the Atlantic rainforest.

The introduction of a species may alter ecological processes of native populations, such as pollination and dispersal patterns, leading to changes in population structure. When the introduced and the native species are congeners, interference in pollination can also lead to hybridization. We aimed to understand the ecological aspects of Euterpe oleracea introduction in the Atlantic forest and the possible consequences for the conservation of the native congener Euterpe edulis. We analysed the population structure of palm populations, including hybrids, and observed the interaction with frugivorous birds of both palm species after E. oleracea introduction. We observed that E. edulis had significantly lower density and a smaller number of seedlings when occurring with E. oleracea. Native and introduced Euterpe species shared nine frugivorous bird species. E. oleracea and hybrids had dispersed outside the original planting area. Consequently, the risks of introduction of E. oleracea may mostly be related to the disruption of interactions between E. edulis and frugivorous birds and the spontaneous production of hybrids. Finally, the cultivation of E. oleracea and hybrids in Atlantic rainforest could affect the conservation of the already endangered E. edulis.

The risks of introduction of the Amazonian palm Euterpe oleracea in the Atlantic rainforest / Os riscos da introdução da palmeira amazônica Euterpe oleracea na Floresta Atlântica

Abstract The introduction of a species may alter ecological processes of native populations, such as pollination and dispersal patterns, leading to changes in population structure. When the introduced and the native species are congeners, interference in pollination can also lead to hybridization. We aimed to understand the ecological aspects of Euterpe oleracea introduction in the Atlantic forest and the possible consequences for the conservation of the native congener Euterpe edulis. We analysed the population structure of palm populations, including hybrids, and observed the interaction with frugivorous birds of both palm species after E. oleracea introduction. We observed that E. edulis had significantly lower density and a smaller number of seedlings when occurring with E. oleracea. Native and introduced Euterpe species shared nine frugivorous bird species. E. oleracea and hybrids had dispersed outside the original planting area. Consequently, the risks of introduction of E. oleracea may mostly be related to the disruption of interactions between E. edulis and frugivorous birds and the spontaneous production of hybrids. Finally, the cultivation of E. oleracea and hybrids in Atlantic rainforest could affect the conservation of the already endangered E. edulis.

Resumo A introdução de uma espécie pode alterar processos ecológicos de populações nativas, tais como padrões de polinização e dispersão, levando a mudanças na estrutura populacional. Quando espécies introduzidas e nativas são congêneres, a interferência na polinização pode levar também à hibridização. Nossos objetivos foram entender os aspectos ecológicos da introdução de Euterpe oleracea na Floresta Atlântica e as possíveis consequências sobre a conservação da congênere nativa Euterpe edulis. Para isso, analisamos a estrutura populacional, incluindo híbridos, e observamos a interação de aves frugívoras com ambas as espécies de palmeira após a introdução de E. oleracea. Observamos que E. edulis apresentou densidade total e número de plântulas menores quando coocorrente com E. oleracea. As palmeiras congenéricas compartilharam nove espécies de aves frugívoras. E. oleracea e híbridos foram dispersos além da área original de plantio. Consequentemente, os riscos da introdução de E. oleracea podem estar principalmente relacionados com o possível deslocamento de interações entre E. edulis e aves frugívoras e com a produção de híbridos. Desta forma, o cultivo de E. oleracea e híbridos podem afetar a conservação da já ameaçada E. edulis.

Implications of Habitat Loss on Seed Predation and Early Recruitment of a Keystone Palm in Anthropogenic Landscapes in the Brazilian Atlantic Rainforest.

Habitat loss is the main driver of the loss of global biodiversity. Knowledge on this subject, however, is highly concentrated on species richness and composition patterns, with little discussion on the consequences of habitat loss for ecological interactions. Therefore, a systemic approach is necessary to maximize the success of conservation efforts by providing more realistic information about the effects of anthropogenic disturbances on natural environmental processes. We investigated the implications of habitat loss for the early recruitment of Euterpe edulis Martius, a keystone palm in the Brazilian Atlantic Forest, in nine sampling sites located in landscapes with different percentages of forest cover (9%-83%). We conducted a paired experiment using E. Edulis seeds set up in experimental stations composed of a vertebrate exclosure versus an open treatment. We used ANCOVA models with treatments as factors to assess the influence of habitat loss on the number of germinated seeds, predation by vertebrates and invertebrates, infestation by fungi, and number of seedlings established. Habitat loss did not affect the probability of transition from a dispersed to a germinated seed. However, when seeds were protected from vertebrate removal, seedling recruitment showed a positive relationship with the amount of forest cover. Seed infestation by fungi was not significant, and seed predation was the main factor limiting seed recruitment. The loss of forest cover antagonistically affected the patterns of seed predation by vertebrates and invertebrates; predation by invertebrates was higher in less forested areas, and predation by vertebrates was higher in forested areas. When seeds were exposed to the action of all biotic mortality factors, the number of recruited seedlings was very low and unrelated to habitat loss. This result indicates that the opposite effects of seed predation by vertebrates and invertebrates mask a differential response of E. edulis recruitment to habitat loss.

Hydraulic architecture and photoinhibition influence spatial distribution of the arborescent palm Euterpe edulis in subtropical forests.

Physiological characteristics of saplings can be considered one of the most basic constraints on species distribution. The shade-tolerant arborescent palm Euterpe edulis Mart. is endemic to the Atlantic Forest of Argentina, Brazil and Paraguay. At a local scale, saplings of this species growing in native forests are absent in gaps. We tested the hypothesis whether sensitivity to photoinhibition or hydraulic architecture constrains the distribution of E. edulis saplings in sun-exposed forest environments. Using shade houses and field studies, we evaluated growth, survival, hydraulic traits and the susceptibility of Photosystem II to photoinhibition in E. edulis saplings under different growth irradiances. Survival rates in exposed sites in the field were very low (a median of 7%). All saplings exhibited photoinhibition when exposed to high radiation levels, but acclimation to a high radiation environment increased the rate of recovery. Petiole hydraulic conductivity was similar across treatments regardless of whether it was expressed per petiole cross-sectional area or per leaf area. At the plant level, investment in conductive tissues relative to leaf area (Huber values) increased with increasing irradiance. Under high irradiance conditions, plants experienced leaf water potentials close to the turgor-loss point, and leaf hydraulic conductance decreased by 79% relative to its maximum value. Euterpe edulis saplings were able to adjust their photosynthetic traits to different irradiance conditions, whereas hydraulic characteristics at the leaf level did not change across irradiance treatments. Our results indicate that uncoupling between water demand and supply to leaves apparently associated with high resistances to water flow at leaf insertion points, in addition to small stems with low water storage capacity, weak stomatal control and high vulnerability of leaves to hydraulic dysfunction, are the main ecophysiological constraints that prevent the growth and survival of E. edulis saplings in gaps in the native forest where native lianas and bamboos show aggressive growth.

Anthocyanins, phenolic acids and antioxidant properties of Juçara fruits (Euterpe edulis M.) along the on-tree ripening process.

Juçara (Euterpe edulis M.) fruits are an interesting source of phenolic compounds, mainly anthocyanins, making them valuable to the food and pharmaceutical industries. Juçara fruits were harvested along the on-tree ripening process between March and June as practiced in Paraná state, Brazil and examined for their total anthocyanin content (TAC), total phenolic content (TPC), total phenolic acid (TPA) and total antioxidant capacity (TAA). Overall, TAC increased (91.52-236.19 mg cyanidin-3-glucoside equivalent/100 g dm) whereas TPC (81.69-49.09 mg GAE/g dm) and TPA (44.27-30.95 mg/100 g dm) decreased during ripening of juçara fruits. Use of tandem mass spectrometry allowed the identification of cyanidin-3,5-diglucoside, peonidin-3-glucoside and peonidin-3-rutinoside for the first time in juçara fruits. The analysis of the phenolic acids by HPLC-MS/MS indicated the presence of gallic, protocatechuic, p-hydroxybenzoic, vanillic, chlorogenic, caffeic, syringic, p-coumaric, sinapinic and ferulic acids. The high antioxidant capacity using DPPH radical scavenging capacity (655.89-745.32 µmol TE/g dm) and ORAC assays (1088.10-2071.55 µmol TE/g dm) showed that juçara fruits have potential as a source of novel natural antioxidants for disease prevention and health promotion, and also as natural food additives for developing new functional food products.