Search Results (52)

Osteoarthritis (OA) is a progressive joint disease that is commonly managed with palliative drugs, many of which are associated with undesirable side effects. This study investigated the therapeutic potential of a novel supplementation with guarana, selenium, and L-carnitine (GSC) in a rat model of chemically induced OA. Forty male Wistar rats (8–9 weeks old) received intra-articular sodium monoiodoacetate (Mia) to induce OA, and were subsequently treated with GSC. Inflammatory and oxidative stress parameters were analyzed at the end of the experiment. GSC supplementation enhanced endogenous antioxidant defenses, suggesting systemic antioxidant activity. However, no histological improvement was observed. In silico analyses indicated that Mia-induced OA may involve a complex molecular environment that GSC, at the tested dose, failed to modulate at the site of injury. Despite the limited local effects, these findings support the systemic benefits of GSC and highlight the potential of natural compound-based strategies in OA management. Given the adverse effects of conventional pharmacotherapy, the development of alternative, naturally derived treatments remains a promising avenue for future research. Full article

The Amazon region’s rich biodiversity supports a bioindustry model that utilizes various biological assets from different plant species, and where it will add value to existing production chains, starting to supply bio industrialized products and not just primary products. Guarana (Paullinia cupana) is rich in bioactive compounds that interest the food and pharmaceutical industries. Thus, the main objective of this review is to present ways to add value to the guarana production chain by developing bioproducts using the residues generated in its processing. During processing, various residues are generated, as follows: peel (corresponding to 30% of the total mass of the fruit), and pulp (aryl), shell, and spent seeds, which have potential for application according to their characteristics. These residues were used to obtain bioactive compounds (catechins, theobromine, and caffeine) through different types of extraction (conventional, enzymatic, and pressurized liquid), and, subsequently, encapsulation. They were also applied in biodegradable and active packaging. Due to the high hemicellulose concentration, residual guarana seeds’ characteristics could potentially produce xylooligosaccharides (XOS). Therefore, the concept of biorefinery applied within the guarana production chain provides products that can be studied in the future to determine which processes are viable for expanding and valuing the productive chain of this fruit, in addition to strengthening sustainable development in the Amazon. Full article

Background: Parkinson’s disease (PD) is a progressive neurodegenerative disorder linked to oxidative stress, mitochondrial dysfunction, and neuroinflammation. This study evaluates the neurofunctional and immunomodulatory effects of an aqueous extract combining cocoa seed husk and guarana powder (GuaCa). Eighteen extracts were characterized by flavonoid and polyphenol content, antioxidant activity, and genoprotective potential. The HCE3 extract, rich in catechins, quercetin, and epigallocatechin gallate, was selected for further analysis in three models: Eisenia fetida earthworms, SH-SY5Y neuron-like cells, and peripheral blood mononuclear cells (PBMCs) from PD patients. Results: The extracts showed antioxidant and genoprotective activity and contained flavonoid. No significant toxicity was observed in Eisenia fetida. In SH-SY5Y cells, GuaCa increased cell viability and brain-derived neurotrophic factor (BDNF) levels and reduced mitochondrial damage by lowering extracellular NDUSF7 (subunit of the NADH dehydrogenase (ubiquinone) complex) levels. In dPD-PBMCs cultures, GuaCa reduced pro-inflammatory cytokine IL-6 levels, indicating immunomodulatory effects. Conclusion: GuaCa shows promise as a nutraceutical for managing neuroinflammation and mitochondrial dysfunction in PD. Further clinical studies are needed to confirm GuaCa extract efficacy and potential for neuroprotective dietary strategies. Full article

Background: guarana and green tea are known as compounds that may improve cognitive performance due to their high content of caffeine and other neurostimulants, such as theobromine in the case of guarana and ECGC (apigalocatechin-3-galate) in that of green tea. Methods: this study investigates the effects of Paullinia cupana (guarana) and Camellia sinensis consumption on students’ intellectual performance. The study group consisted of 33 students, mostly women, from various faculties. During the studied period, they consumed 2 g guarana per day for ten days and 1.5 g green tea per day for ten days. The students completed three cognitive tests before and after administration of the products, measuring reaction speed, memory, and attention. They also completed questionnaires regarding health status, product information, product quality, purchase intention, consumer confidence in the product, and perception of effects and preferences. Results and discussion: the results showed that both guarana and green tea fostered significant improvements in cognitive performance. However, more people felt the effect of guarana than the effect of green tea. The study found a strong correlation between cognitive effects and guarana administration, including improvements in energy and retention of information. For green tea, a calming effect and state of well-being were the most relevant responses. Conclusions: the findings suggest that guarana and green tea may constitute a useful strategy for improving academic performance. However, further research is needed to determine optimal doses, frequency of consumption, and potential long-term effects on cognitive function. Full article

Background: Paullinia cupana Kunth, popularly known as guarana, a native Amazonian shrub cultivated by the Sateré-Mawé ethnic group, has been used in traditional medicine for various purposes, including stimulant and therapeutic actions, due to its chemical composition, which is rich in bioactive compounds. This study explored the reductive potential of guarana with nanobiotechnology and aimed to synthesize silver nanoparticles (AgNPs) using the aqueous extract of leaves collected during the dry and rainy seasons, assessing their biological and catalytic activities. Methods: The AgNPs were synthesized in a water bath at 70 °C for three hours and then characterized using techniques such as UV-Vis spectroscopy, DLS, zeta potential, MET, NTA, and EDX and had their effects on various biological systems assessed in vitro, as well as in catalytic tests aimed at indicating the probable influence of the time when the plant material was collected on the properties of the nanostructures. Results: The AgNPs had an average diameter between 39.33 and 126.2 nm, spherical morphology, absorption bands between 410 and 450 nm, and high colloidal stability over two years. The biological results showed antibacterial activity against all the species tested, as well as remarkable antioxidant action against DPPH and ABTS free radicals, in the same way as the aqueous leaf extracts of P. cupana, in addition to cytotoxic properties against cancerous (A431 and A549) and non-cancerous (HaCaT and HNTMC) cells. The AgNPs were active against promastigote forms of Leishmania (Leishmania) amazonensis while not affecting the viability of macrophages, and from the LC₅₀ and LC₉₀ values, the AgNPs were more effective than the metal salt solution in controlling Aedes aegypti larvae and pupae. We also reported that the catalytic degradation of the organic dyes methylene blue (MB) and methyl orange (MO) by AgNPs was over 90% after 40 or 14 min, respectively. Conclusions: Thus, our results support the potential of seasonal extracts of guarana leaves to produce AgNPs with diverse application possibilities for the health, industrial, and environmental sectors. Full article

This study addresses the urgent need for effective methods to monitor and conserve Araucaria angustifolia, a critically endangered species of immense ecological and cultural significance in southern Brazil. Using high-resolution satellite images from Google Earth, we apply the YOLOv7x deep learning model to detect this species in two distinct urban contexts in Curitiba, Paraná: isolated trees across the urban landscape and A. angustifolia individuals within forest remnants. Data augmentation techniques, including image rotation, hue and saturation adjustments, and mosaic augmentation, were employed to increase the model’s accuracy and robustness. Through a 5-fold cross-validation, the model achieved a mean Average Precision (AP) of 90.79% and an F1-score of 88.68%. Results show higher detection accuracy in forest remnants, where the homogeneous background of natural landscapes facilitated the identification of trees, compared to urban areas where complex visual elements like building shadows presented challenges. To reduce false positives, especially misclassifications involving palm species, additional annotations were introduced, significantly enhancing performance in urban environments. These findings highlight the potential of integrating remote sensing with deep learning to automate large-scale forest inventories. Furthermore, the study highlights the broader applicability of the YOLOv7x model for urban forestry planning, offering a cost-effective solution for biodiversity monitoring. The integration of predictive data with urban forest maps reveals a spatial correlation between A. angustifolia density and the presence of forest fragments, suggesting that the preservation of these areas is vital for the species’ sustainability. The model’s scalability also opens the door for future applications in ecological monitoring across larger urban areas. As urban environments continue to expand, understanding and conserving key species like A. angustifolia is critical for enhancing biodiversity, resilience, and addressing climate change. Full article

The guaraná tree is a species known for the stimulating properties found in its seeds, leading to increased consumption and promising production. Cultivation is primarily carried out in family farming systems, and one of the challenges in the production process is the acquisition of seedlings. The conventional nursery system, which employs intermittent misting for the production of guaraná clones, raises the cost of seedlings, necessitating the exploration of alternatives to this approach. The aim of this study was to evaluate different conditions as alternatives to the conventional nursery system for rooting guaraná cuttings. The experimental design was entirely randomized, featuring three guaraná genotypes, BRS Maués, BRS CG 611, and BRS Luzeia, alongside two rooting conditions, the conventional nursery and a humid chamber with nebulization, with four repetitions. The rooting of guaraná clones was significantly influenced by the interaction between conditions and genotypes. The humid chamber with nebulization demonstrated superior root system characteristics among the tested conditions, with a rooting rate of 56.66% for BRS Luzeia. This method proved to be efficient and accessible for small producers, making it a satisfactory option for rooting guaraná trees. Full article

Caffeine is an alkaloid belonging to the methylated xanthine family. It is found in various foods of plant origin, including tea leaves, guarana berries, and coffee beans. Due to its stimulating effect on the central nervous system and the associated increase in alertness and reduction in tiredness, caffeine is specifically added to some foods, such as food supplements. Claims about the positive physiological effects of caffeine are health claims within the definition of the European Union (EU) Health Claims Regulation and must be authorised before use. Despite a positive opinion from the European Food Safety Authority, regulation of the authorisation of caffeine claims was rejected due to a veto by the European Parliament. As a result, health claims are currently not regulated for caffeine in all EU member states, and the transitional on-hold status also no longer applies for most claims. Therefore, products with health claims regarding caffeine are still observed within the context of governmental food-control activities. To investigate how these are currently used on the market, internet research (n = 188) was carried out. The sample included foods that naturally contain caffeine or to which it is frequently added, namely coffee, tea, non-alcoholic soft drinks and mixed drinks, as well as food supplements, including sports nutrition products. Furthermore, the labelling of official samples that were conspicuous in relation to caffeine in the years 2019–2023 (n = 136) was included in the evaluation. The products most frequently advertised with unregulated health claims for caffeine were food supplements (31% of 135 products). On the other hand, health claims were least frequently used for coffee (4% of 77 products) and tea (18% of 33 products). For all product groups, health claims were mainly made regarding improved concentration and performance/energy. The individual effects the health claims referred to differed between the product groups. In the case of coffee and tea, the advertised effects are mainly limited to increased energy and performance in the form of a “kick” or “boost”. A wider range of different health claims are used for food supplements and alcohol-free beverages, including claims relating to stamina and alertness. In general, the tendency was observed for health claims to be advertised more frequently on the internet than on the product labelling itself. This study exposes a critical issue: while scientific evidence supports some health claims for caffeine, they still remain unregulated, complicating enforcement and creating public confusion. Prompt regulatory revision is needed to align these claims with scientific validations, ensuring both accuracy and regulatory compliance. Full article

The green synthesis of silver nanoparticles (AgNPs) can be developed using safe and environmentally friendly routes, can replace potentially toxic chemical methods, and can increase the scale of production. This study aimed to synthesize AgNPs from aqueous extracts of guarana (Paullinia cupana) leaves and flowers, collected in different seasons of the year, as a source of active biomolecules capable of reducing silver ions (Ag⁺) and promoting the stabilization of colloidal silver (Ag⁰). The plant aqueous extracts were characterized regarding their metabolic composition by liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS/MS), phenolic compound content, and antioxidant potential against free radicals. The synthesized AgNPs were characterized by UV/Vis spectrophotometry, dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), and scanning electron microscopy coupled to energy-dispersive X-ray spectrometry (EDX). The results demonstrated that the chemical characterization indicated the presence of secondary metabolites of many classes of compounds in the studied aqueous extracts studied, but alkaloids and flavonoids were predominant, which are widely recognized for their antioxidant capabilities. It was possible to notice subtle changes in the properties of the nanostructures depending on parameters such as seasonality and the part of the plant used, with the AgNPs showing surface plasmon resonance bands between 410 and 420 nm using the leaf extract and between 440 and 460 nm when prepared using the flower extract. Overall, the average hydrodynamic diameters of the AgNPs were similar among the samples (61.98 to 101.6 nm). Polydispersity index remained in the range of 0.2 to 0.4, indicating that colloidal stability did not change with storage time. Zeta potential was above −30 mV after one month of analysis, which is adequate for biological applications. TEM images showed AgNPs with diameters between 40.72 to 48.85 nm and particles of different morphologies. EDX indicated silver content by weight between 24.06 and 28.81%. The synthesized AgNPs exhibited antimicrobial efficacy against various pathogenic microorganisms of clinical and environmental interest, with MIC values between 2.12 and 21.25 µg/mL, which is close to those described for MBC values. Therefore, our results revealed the potential use of a native species of plant from Brazilian biodiversity combined with nanotechnology to produce antimicrobial agents. Full article

When looking for new ingredients to process red meat, poultry, and fish products, it is essential to consider using vegetable resources that can replace traditional ingredients such as animal fat and synthetic antioxidants that may harm health. The Amazon, home to hundreds of edible fruit species, can be a viable alternative for new ingredients in processing muscle food products. These fruits have gained interest for their use as natural antioxidants, fat replacers, colorants, and extenders. Some of the fruits that have been tested include açai, guarana, annatto, cocoa bean shell, sacha inchi oil, and peach palm. Studies have shown that these fruits can be used as dehydrated products or as liquid or powder extracts in doses between 250 and 500 mg/kg as antioxidants. Fat replacers can be added directly as flour or used to prepare emulsion gels, reducing up to 50% of animal fat without any detrimental effects. However, oxidation problems of the gels suggest that further investigation is needed by incorporating adequate antioxidant levels. In low doses, Amazon fruit byproducts such as colorants and extenders have been shown to have positive technological and sensory effects on muscle food products. While evidence suggests that these fruits have beneficial health effects, their in vitro and in vivo nutritional effects should be evaluated in muscle food products containing these fruits. This evaluation needs to be intended to identify safe doses, delay the formation of key oxidation compounds that directly affect health, and investigate other factors related to health. Full article

Guarana (GUA), a Brazilian seed extract, contains caffeine and other bioactive compounds that may have psychoactive effects. To assess the acute effects of GUA compared to a low dose of caffeine (CAF) on cognitive and mood parameters, twenty participants completed a double-blind, crossover experiment where they ingested capsules containing the following: (1) 100 mg CAF, (2) 500 mg GUA containing 130 mg caffeine, or (3) placebo (PLA). Cognitive tests (Simon and 2N-Back Task) were performed at the baseline (pre-ingestion) and 60 min after ingestion. The response time for the cognitive tests and heart rate variability were unaffected (p > 0.05) by treatment, although 2N-Back was overall faster (p = 0.001) across time. The accuracy in the 2N-Back Task showed a significant interaction effect (p = 0.029) due to higher post-ingestion versus pre-ingestion levels (p = 0.033), but only with the PLA. The supplements also had no effect on cognitive measures following physical fatigue (n = 11). There was an interaction effect on perceived mental energy, where the pre-ingestion of GUA had lower mental pep ratings compared to post-ingestion (p = 0.006) and post-exercise (p = 0.018) levels. Neither the acute ingestion of GUA nor low dose of CAF influenced cognitive performance or provided consistent benefit on mood or mental workload through vagal modulation. Additional investigations are beneficial to determining the lowest effective dose for CAF or GUA to influence mood and/or cognitive performance. Full article

Aminobisphosphonates (NBPs) are the first-choice medication for osteoporosis (OP); NBP treatment aims at increasing bone mineral density (BMD) by inhibiting the activity of farnesyl diphosphate synthase (FDPS) enzyme in osteoclasts. Despite its efficacy, inadequate response to the drug and side effects have been reported. The A allele of the rs2297480 (A > C) SNP, found in the regulatory region of the FDPS gene, is associated with reduced gene transcription. This study evaluates the FDPS variant rs2297480 (A > C) association with OP patients’ response to alendronate sodium treatment. A total of 304 OP patients and 112 controls were enrolled; patients treated with alendronate sodium for two years were classified, according to BMD variations at specific regions (lumbar spine (L1-L4), femoral neck (FN) and total hip (TH), as responders (OP-R) (n = 20) and non-responders (OP-NR) (n = 40). We observed an association of CC genotype with treatment failure (p = 0.045), followed by a BMD decrease in the regions L1-L4 (CC = −2.21% ± 2.56; p = 0.026) and TH (CC = −2.06% ± 1.84; p = 0.015) after two years of alendronate sodium treatment. Relative expression of the FDPS gene was also evaluated in OP-R and OP-NR patients. Higher expression of the FDPS gene was also observed in OP-NR group (FC = 1.84 ± 0.77; p = 0.006) when compared to OP-R. In conclusion, the influence observed of FDPS expression and the rs2897480 variant on alendronate treatment highlights the importance of a genetic approach to improve the efficacy of treatment for primary osteoporosis. Full article

The processes of occupation and exploitation in the Amazon have been increasing, and as a consequence, forest areas are being replaced by agroecosystems. As a consequence of this change, changes have been occurring in the soil attributes, and consequently, in the stability of aggregates in these environments. Thus, this work had two objectives: the first was to evaluate the impacts generated by the conversion of forests into agroecosystems on the soil attributes that are related to aggregates, in the southwestern region of the Amazon; the second objective was to evaluate the roles of pedophysical and pedochemical parameters on the stability of soil aggregates. The study was carried out on rural properties located in the southern part of Amazonas State, Brazil. Eight areas under different agroecosystems were selected: in the municipality of Canutama: (i) annatto, (ii) guarana, and (iii) cupuassu; in the municipality of Humaitá: (iv) cassava, (v) agroforestry, and (vi) sugarcane; and in the municipality of Manicoré: (vii) pasture and (viii) native forest. Unformed soil samples were collected from the 0.00–0.10 m layer and analyzed for aggregate stability, bulk density, soil organic carbon, and soil organic carbon stock. Univariate, bivariate, and multivariate analyses were performed. The largest soil aggregations occurred in the annatto, guarana, sugarcane, and pasture agroecosystems. We associate the greater aggregation capacity of soils with factors that are inherent to the cultivated species and soil properties. The first factor corresponds to the adaptability of the Amazonian and grass species and their ability to produce biomass. The second factor is related to the physical and chemical properties of Amazonian soils, largely influenced by the sand fraction, soil organic carbon, soil acidity, and availability of exchangeable Ca and Mg. Full article

The seed yield of guarana (Paullinia cupana H.B.K. var. sorbilis) is affected by weeds. Management is difficult for Amazon farmers and ranchers, owing to the hot and humid climate prevailing in the region, which makes mechanical control inefficient and leads farmers to the decision to use herbicides. Herbicide damage to this species is unknown. The objective of this study was to evaluate glyphosate damage to the development and quality of guarana seedlings. The treatments consisted of glyphosate doses at concentrations of 0, 126, 252, 540, 1080, 2160 and 3240 g a.e. ha⁻¹ and were evaluated for 60 days, in two applications. Analyses were performed for biometrics, seedling development, anthracnose and Injury characteristics. Glyphosate caused symptoms of Injury in all doses applied, but lower doses did not interfere with seedling growth and development. There was a correlation between anthracnose severity and increased glyphosate dose. When applied correctly, glyphosate can be an integrated weed management tool for use in guarana crops. Full article

Caffeine is a natural psychoactive substance that belongs to a group of chemical compounds called purine alkaloids. Caffeine is found in various plants such as coffee, tea, cocoa, guarana, and yerba mate. It is often added to dietary supplements for its ability to increase metabolism and aid in weight loss. To determine the caffeine content in dietary supplements, a novel UHPLC method was developed, compatible with the rules of green analytical chemistry. The developed method used only water and ethanol for sample preparation and chromatographic separation on a short C18 column. The obtained method confirmed that caffeine may be analyzed using only environmentally friendly solvents, ethanol, and water. The developed method is characterized by its low limit of quantitation, equal to 0.047 µg/mL, and good reproducibility (a relative standard deviation lower than 1.1%). The obtained results show that the caffeine content in tested dietary supplements is 4–35% higher than the declared amount in most cases. In comparison, the caffeine content of the drug determined using this method was performed with an accuracy of 0.4% RSD. Full article