Protective Potential of a Botanical-Based Supplement Ingredient against the Impact of Environmental Pollution on Cutaneous and Cardiopulmonary Systems: Preclinical Study.

Air pollution is a growing threat to human health. Airborne pollution effects on respiratory, cardiovascular and skin health are well-established. The main mechanisms of air-pollution-induced health effects involve oxidative stress and inflammation. The present study evaluates the potential of a polyphenol-enriched food supplement ingredient comprising Lippia citriodora, Olea europaea, Rosmarinus officinalis, and Sophora japonica extracts in mitigating the adverse effects of environmental pollution on skin and cardiopulmonary systems. Both in vitro and ex vivo studies were used to assess the blend's effects against pollution-induced damage. In these studies, the botanical blend was found to reduce lipid peroxidation, inflammation (by reducing IL-1α), and metabolic alterations (by regulating MT-1H, AhR, and Nrf2 expression) in human skin explants exposed to a mixture of pollutants. Similar results were also observed in keratinocytes exposed to urban dust. Moreover, the ingredient significantly reduced pollutant-induced ROS production in human endothelial cells and lung fibroblasts, while downregulating the expression of apoptotic genes (bcl-2 and bax) in lung fibroblasts. Additionally, the blend counteracted the effect of urban dust on the heart rate in zebrafish embryos. These results support the potential use of this supplement as an adjuvant method to reduce the impact of environmental pollution on the skin, lungs, and cardiovascular tissues.

Encapsulation of polyphenols in protein-based nanoparticles: Preparation, properties, and applications.

Polyphenols have a variety of physiological activities, including antioxidant, antimicrobial, and anti-inflammatory properties. However, their applications are often limited because due to the instability of polyphenols. Encapsulation technologies can be employed to overcome these problems and increase the utilization of polyphenols. In this article, the utilization of protein-based nanoparticles for encapsulating polyphenols is reviewed due to their good biocompatibility, biodegradability, and functional attributes. Initially, the various kinds of animal and plant proteins available for forming protein nanoparticles are discussed, as well as the fabrication methods that can be used to assemble these nanoparticles. The molecular interaction mechanisms between proteins and polyphenols are then summarized. Applications of protein-based nanoparticles for encapsulating polyphenols are then discussed, including as nutrient delivery systems, in food packaging materials, and in the creation of functional foods. Finally, areas where further research is need on the development, characterization, and application of protein-based polyphenol-loaded nanoparticles are highlighted.

Pseudomonas syringae senses polyphenols via phosphorelay crosstalk to inhibit virulence.

Bacteria use a variety of mechanisms, such as two-component regulatory systems (TCSs), to rapidly sense and respond to distinct conditions and signals in their host organisms. For example, a type III secretion system (T3SS) is a key determinant of the virulence of the model plant pathogen Pseudomonas syringae and contains the TCS RhpRS as a key regulator. However, the plant-derived compound targeting RhpRS remains unknown. Here, we report that RhpRS directly interacts with polyphenols and responds by switching off P. syringae T3SS via crosstalk with alternative histidine kinases. We identify three natural polyphenols that induce the expression of the rhpRS operon in an RhpS-dependent manner. The presence of these three specific polyphenols inhibits the phosphatase activity of RhpS, thus suppressing T3SS activation in T3SS-inducing conditions. The Pro40 residue of RhpS is essential to respond to these polyphenols. In addition, three non-cognate histidine kinases cooperatively phosphorylate RhpR and antagonize the rhpS mutant phenotype. This work illustrates that plant polyphenols can directly target P. syringae RhpRS, which results in bacterial virulence being switched off via a phosphorylation-related crosstalk.

Microbial synthesis of the plant natural product precursor p-coumaric acid with Corynebacterium glutamicum.

BACKGROUND: Phenylpropanoids such as p-coumaric acid represent important precursors for the synthesis of a broad range of plant secondary metabolites including stilbenoids, flavonoids, and lignans, which are of pharmacological interest due to their health-promoting properties. Although extraction from plant material or chemical synthesis is possible, microbial synthesis of p-coumaric acid from glucose has the advantage of being less expensive and more resource efficient. In this study, Corynebacterium glutamicum was engineered for the production of the plant polyphenol precursor p-coumaric acid from glucose. RESULTS: Heterologous expression of the tyrosine ammonia-lyase encoding gene from Flavobacterium johnsoniae enabled the conversion of endogenously provided tyrosine to p-coumaric acid. Product consumption was avoided by abolishing essential reactions of the phenylpropanoid degradation pathway. Accumulation of anthranilate as a major byproduct was eliminated by reducing the activity of anthranilate synthase through targeted mutagenesis to avoid tryptophan auxotrophy. Subsequently, the carbon flux into the shikimate pathway was increased, phenylalanine biosynthesis was reduced, and phosphoenolpyruvate availability was improved to boost p-coumaric acid accumulation. A maximum titer of 661 mg/L p-coumaric acid (4 mM) in defined mineral medium was reached. Finally, the production strain was utilized in co-cultivations with a C. glutamicum strain previously engineered for the conversion of p-coumaric acid into the polyphenol resveratrol. These co-cultivations enabled the synthesis of 31.2 mg/L (0.14 mM) resveratrol from glucose without any p-coumaric acid supplementation. CONCLUSIONS: The utilization of a heterologous tyrosine ammonia-lyase in combination with optimization of the shikimate pathway enabled the efficient production of p-coumaric acid with C. glutamicum. Reducing the carbon flux into the phenylalanine and tryptophan branches was the key to success along with the introduction of feedback-resistant enzyme variants.

Synthesis of Flavonol-Bearing Probes for Chemoproteomic and Bioinformatic Analyses of Asteraceae Petals in Search of Novel Flavonoid Enzymes.

This study aimed at searching for the enzymes that are responsible for the higher hydroxylation of flavonols serving as UV-honey guides for pollinating insects on the petals of Asteraceae flowers. To achieve this aim, an affinity-based chemical proteomic approach was developed by relying on the use of quercetin-bearing biotinylated probes, which were thus designed and synthesized to selectively and covalently capture relevant flavonoid enzymes. Proteomic and bioinformatic analyses of proteins captured from petal microsomes of two Asteraceae species (Rudbeckia hirta and Tagetes erecta) revealed the presence of two flavonol 6-hydroxylases and several additional not fully characterized proteins as candidates for the identification of novel flavonol 8-hydroxylases, as well as relevant flavonol methyl- and glycosyltransferases. Generally speaking, this substrate-based proteome profiling methodology constitutes a powerful tool for the search for unknown (flavonoid) enzymes in plant protein extracts.

Possible Mechanisms of Oxidative Stress-Induced Skin Cellular Senescence, Inflammation, and Cancer and the Therapeutic Potential of Plant Polyphenols.

As the greatest defense organ of the body, the skin is exposed to endogenous and external stressors that produce reactive oxygen species (ROS). When the antioxidant system of the body fails to eliminate ROS, oxidative stress is initiated, which results in skin cellular senescence, inflammation, and cancer. Two main possible mechanisms underlie oxidative stress-induced skin cellular senescence, inflammation, and cancer. One mechanism is that ROS directly degrade biological macromolecules, including proteins, DNA, and lipids, that are essential for cell metabolism, survival, and genetics. Another one is that ROS mediate signaling pathways, such as MAPK, JAK/STAT, PI3K/AKT/mTOR, NF-κB, Nrf2, and SIRT1/FOXO, affecting cytokine release and enzyme expression. As natural antioxidants, plant polyphenols are safe and exhibit a therapeutic potential. We here discuss in detail the therapeutic potential of selected polyphenolic compounds and outline relevant molecular targets. Polyphenols selected here for study according to their structural classification include curcumin, catechins, resveratrol, quercetin, ellagic acid, and procyanidins. Finally, the latest delivery of plant polyphenols to the skin (taking curcumin as an example) and the current status of clinical research are summarized, providing a theoretical foundation for future clinical research and the generation of new pharmaceuticals and cosmetics.

Effects of Plant-Derived Polyphenols on the Antioxidant Activity and Aroma of Sulfur-Dioxide-Free Red Wine.

Significant efforts have been made in recent years to produce healthier wines, with the primary goal of reducing the use of sulfur dioxide (SO2), which poses health risks. This study aimed to assess the effectiveness of three plant-derived polyphenols (dihydromyricetin, resveratrol, and catechins) as alternatives to SO2 in wine. After a three-month aging process, the wines were evaluated using analytical techniques such as high-performance liquid chromatography, colorimetry, gas chromatography-olfactometry-mass spectrometry, as well as electronic nose and electronic tongue analyses, with the purpose to assess parameters including antioxidant activity, color, contents of volatile aroma compounds, and sensory characteristics. The results demonstrated various degrees of improvement in the antioxidant activity, aromatic intensity, and sensory characteristics of wines using polyphenols. Notably, dihydromyricetin (200 mg/L) exhibited the strongest antioxidant activity, with increases of 18.84%, 23.28%, and 20.87% in 2,2-diphenyl-1-picrylhydrazyl, 2,2'azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), and ferric-ion-reducing antioxidant power assays, respectively. Resveratrol (200 mg/L) made the most significant contribution to volatile aroma compounds, with an 8.89% increase in the total content of alcohol esters. In E-nose analysis, catechins (200 mg/L) showed the highest response to aromatic compounds and the lowest response to volatile sulfur compounds, while also exhibiting the best sensory characteristics. Therefore, the three plant-derived polyphenols investigated here exhibited the potential to enhance wine quality as alternatives to SO2. However, it is important to consider the specific impact of different polyphenols on wine; hence, suitable antioxidants should be selected in wine production according to specific requirements.

Plant polyphenols regulating myoglobin oxidation and color stability in red meat and certain fish: A review.

Color is an essential criterion for assessing the freshness, quality, and acceptability of red meat and certain fish with red muscle. Myoglobin (Mb), one of the significant pigment substances, is the uppermost reason to keep the color of red meat. Their oxidation and browning are easy to occur throughout the storage and processing period. Natural antioxidants are substances with antioxidant activity extracted from plants, such as plant polyphenols. Consumers prefer natural antioxidants due to safety concerns and limitations on the use of synthetic antioxidants. In recent years, plant polyphenols have been widely used as antioxidants to slow down the deterioration of product quality due to oxidation. As natural antioxidants, it is necessary to strengthen the researches on the antioxidant mechanism of plant polyphenols to solve the discoloration of red meat and certain fish. A fundamental review of the relationship between Mb oxidation and color stability is discussed. The inhibiting mechanisms of polyphenols on lipid and Mb oxidation are presented and investigated. Meanwhile, this review comprehensively outlines applications of plant polyphenols in improving color stability. This will provide reference and theoretical support for the rational application of plant polyphenols in green meat processing.

Detection and Imaging of the Plant Pathogen Response by Near-Infrared Fluorescent Polyphenol Sensors.

Plants use secondary metabolites such as polyphenols for chemical defense against pathogens and herbivores. Despite their importance in plant pathogen interactions and tolerance to diseases, it remains challenging to detect polyphenols in complex plant tissues. Here, we create molecular sensors for plant polyphenol imaging that are based on near-infrared (NIR) fluorescent single-wall carbon nanotubes (SWCNTs). We identified polyethylene glycol-phospholipids that render (6,5)-SWCNTs sensitive (Kd =90 nM) to plant polyphenols (tannins, flavonoids, …), which red-shift (up to 20 nm) and quench their emission (ca. 1000 nm). These sensors report changes in total polyphenol level after herbivore or pathogen challenge in crop plant systems (Soybean Glycine max) and leaf tissue extracts (Tococa spp.). We furthermore demonstrate remote chemical imaging of pathogen-induced polyphenol release from roots of soybean seedlings over the time course of 24 h. This approach allows in situ visualization and understanding of the chemical plant defense in real time and paves the way for plant phenotyping for optimized polyphenol secretion.

Dietary Plant Polyphenols: Effects of Food Processing on Their Content and Bioavailability.

Dietary plant polyphenols are natural bioactive compounds that are increasingly attracting the attention of food scientists and nutritionists because of their nutraceutical properties. In fact, many studies have shown that polyphenol-rich diets have protective effects against most chronic diseases. However, these health benefits are strongly related to both polyphenol content and bioavailability, which in turn depend on their origin, food matrix, processing, digestion, and cellular metabolism. Although most fruits and vegetables are valuable sources of polyphenols, they are not usually consumed raw. Instead, they go through some processing steps, either industrially or domestically (e.g., cooling, heating, drying, fermentation, etc.), that affect their content, bioaccessibility, and bioavailability. This review summarizes the status of knowledge on the possible (positive or negative) effects of commonly used food-processing techniques on phenolic compound content and bioavailability in fruits and vegetables. These effects depend on the plant type and applied processing parameters (type, duration, media, and intensity). This review attempts to shed light on the importance of more comprehensive dietary guidelines that consider the recommendations of processing parameters to take full advantage of phenolic compounds toward healthier foods.

Phenolic Profile, Antioxidant Capacity and Antimicrobial Activity of Nettle Leaves Extracts Obtained by Advanced Extraction Techniques.

Nettle is a widely known plant whose high biological activity and beneficial medicinal effects are attributed to various bioactive compounds, among which polyphenols play an important role. In order to isolate polyphenols and preserve their properties, advanced extraction techniques have been applied to overcome the drawbacks of conventional ones. Therefore, microwave-assisted extraction (MAE) has been optimized for the isolation of nettle leaves polyphenols and it was compared to pressurized liquid extraction (PLE) and conventional heat-reflux extraction (CE). The obtained extracts were analyzed for their individual phenolic profile by UPLC MS2 and for their antioxidant capacity by ORAC assay. MAE proved to be the more specific technique for the isolation of individual phenolic compounds, while PLE produced extracts with higher amount of total phenols and higher antioxidant capacity. Both techniques were more effective compared to CE. PLE nettle extract showed antimicrobial activity against bacteria, especially against Gram-negative Pseudomonas fragi ATCC 4973 and Campylobacter jejuni NCTC 11168 strains. This suggests that PLE is suitable for obtaining a nettle extract with antioxidant and antimicrobial potential, which as such has great potential for use as a value-added ingredient in the food and pharmaceutical industry.

Potassium channels on smooth muscle as a molecular target for plant-derived Resveratrol.

Resveratrol (3,5,4'-trihydroxy-trans-stilbene) is a phytoalexin present in a variety of plant species. Resveratrol has a wide spectrum of pharmacologic properties, and it exhibits versatile biological effects on different human and animal models. The studies have shown that potassium (K) channels can be potential targets in the mechanism of resveratrol action. K channels play a crucial role in maintaining membrane potential. Inhibition of K channels causes membrane depolarization and then contraction of smooth muscles, while the activation leads to membrane hyperpolarization and subsequently, relaxation. Five diverse types of K channels have been identified in smooth muscle cells in different tissue: ATP-sensitive K channels (KATP), voltage-dependent K channels (Kv), Ca2+ - and voltage-dependent K channels (BKCa), inward rectifier K channels (Kir), and tandem two-pore K channels (K2P). The expression and activity of K channels altered in many types of diseases. Aberrant function or expression of K channels can be underlying in pathologies such as cardiac arrhythmia, diabetes mellitus, hypertension, preterm birth, preeclampsia, and various types of cancer. Modulation of K channel activity by molecular approaches and selective drug development may be a novel treatment modality for these dysfunctions in the future. The plant-derived non-toxic polyphenols, such as resveratrol, can alter K channel activity and lead to the desired outcome. This review presents the basic properties, physiological, pathophysiological functions of K channels, and pharmacological roles of resveratrol on the major types of K channels that have been determined in smooth muscle cells.

Healthy Effects of Plant Polyphenols: Molecular Mechanisms.

The increasing extension in life expectancy of human beings in developed countries is accompanied by a progressively greater rate of degenerative diseases associated with lifestyle and aging, most of which are still waiting for effective, not merely symptomatic, therapies. Accordingly, at present, the recommendations aimed at reducing the prevalence of these conditions in the population are limited to a safer lifestyle including physical/mental exercise, a reduced caloric intake, and a proper diet in a convivial environment. The claimed health benefits of the Mediterranean and Asian diets have been confirmed in many clinical trials and epidemiological surveys. These diets are characterized by several features, including low meat consumption, the intake of oils instead of fats as lipid sources, moderate amounts of red wine, and significant amounts of fresh fruit and vegetables. In particular, the latter have attracted popular and scientific attention for their content, though in reduced amounts, of a number of molecules increasingly investigated for their healthy properties. Among the latter, plant polyphenols have raised remarkable interest in the scientific community; in fact, several clinical trials have confirmed that many health benefits of the Mediterranean/Asian diets can be traced back to the presence of significant amounts of these molecules, even though, in some cases, contradictory results have been reported, which highlights the need for further investigation. In light of the results of these trials, recent research has sought to provide information on the biochemical, molecular, epigenetic, and cell biology modifications by plant polyphenols in cell, organismal, animal, and human models of cancer, metabolic, and neurodegenerative pathologies, notably Alzheimer's and Parkinson disease. The findings reported in the last decade are starting to help to decipher the complex relations between plant polyphenols and cell homeostatic systems including metabolic and redox equilibrium, proteostasis, and the inflammatory response, establishing an increasingly solid molecular basis for the healthy effects of these molecules. Taken together, the data currently available, though still incomplete, are providing a rationale for the possible use of natural polyphenols, or their molecular scaffolds, as nutraceuticals to contrast aging and to combat many associated pathologies.

Recent advances in metabolic engineering of Corynebacterium glutamicum for bioproduction of value-added aromatic chemicals and natural products.

Recent progress in synthetic and systems metabolic engineering technologies has explored the potential of microbial cell factories for the production of industrially relevant bulk and fine chemicals from renewable biomass resources in an eco-friendly manner. Corynebacterium glutamicum, a workhorse for industrial amino acid production, has currently evolved into a promising microbial platform for bioproduction of various natural and non-natural chemicals from renewable feedstocks. Notably, it has been recently demonstrated that metabolically engineered C. glutamicum can overproduce several commercially valuable aromatic and related chemicals such as shikimate, 4-hydroxybenzoate, and 4-aminobenzoate from sugars at remarkably high titer suitable to commercial application. On the other hand, overexpression and/or extension of its endogenous metabolic pathways by integrating heterologous metabolic pathways enabled production of structurally intricate and valuable natural chemicals like plant polyphenols, carotenoids, and fatty acids. In this review, we summarize recent advances in metabolic engineering of C. glutamicum for production of those value-added aromatics and other natural products, which highlights high potential and the versatility of this microbe for bioproduction of diverse chemicals.

Dietary phytochemicals as epigenetic modifiers in cancer: Promise and challenges.

The influence of diet and environment on human health has been known since ages. Plant-derived natural bioactive compounds (phytochemicals) have acquired an important role in human diet as potent antioxidants and cancer chemopreventive agents. In past few decades, the role of epigenetic alterations such as DNA methylation, histone modifications and non-coding RNAs in the regulation of mammalian genome have been comprehensively addressed. Although the effects of dietary phytochemicals on gene expression and signaling pathways have been widely studied in cancer, the impact of these dietary compounds on mammalian epigenome is rapidly emerging. The present review outlines the role of different epigenetic mechanisms in the regulation and maintenance of mammalian genome and focuses on the role of dietary phytochemicals as epigenetic modifiers in cancer. Above all, the review focuses on summarizing the progress made thus far in cancer chemoprevention with dietary phytochemicals, the heightened interest and challenges in the future.

Anti-inflammatory and antioxidant effects of polyphenols extracted from Antirhea borbonica medicinal plant on adipocytes exposed to Porphyromonas gingivalis and Escherichia coli lipopolysaccharides.

In obesity, gut microbiota LPS may translocate into the blood stream and then contribute to adipose tissue inflammation and oxidative stress, leading to insulin resistance. A causal link between periodontal infection, obesity and type 2 diabetes has also been suggested. We evaluated the ability of polyphenols from Antirhea borbonica medicinal plant to improve the inflammatory and redox status of 3T3-L1 adipocytes exposed to LPS of Porphyromonas gingivalis periodontopathogen or Escherichia coli enterobacteria. Our results show that LPS enhanced the production of Toll-like receptor-dependent MyD88 and NFκB signaling factors as well as IL-6, MCP-1, PAI-1 and resistin. Plant polyphenols reduced LPS pro-inflammatory action. Concomitantly, polyphenols increased the production of adiponectin and PPARγ, known as key anti-inflammatory and insulin-sensitizing mediators. Moreover, both LPS increased intracellular ROS levels and the expression of genes encoding ROS-producing enzymes including NOX2, NOX4 and iNOS. Plant polyphenols reversed these effects and up-regulated MnSOD and catalase antioxidant enzyme gene expression. Noticeably, preconditioning of cells with caffeic acid, chlorogenic acid or kaempferol identified among A. borbonica major polyphenols, led to similar protective properties. Altogether, these findings demonstrate the anti-inflammatory and antioxidant effects of A. borbonica polyphenols on adipocytes, in response to P. gingivalis or E. coli LPS. It will be of major interest to assess A. borbonica polyphenol benefits against obesity-related metabolic disorders such as insulin resistance in vivo.

Antibiofilm Activity of Plant Polyphenols.

In the history of human medicine, antibiotics represent epochal examples of medical progress. However, with an approaching antibiotic crisis due to the emergence and extensive spread of antimicrobial resistance among bacterial agents, as well as to increasing number of patients with chronic and recalcitrant bacterial biofilm-associated infections, the naturally occurring molecules may become new sources of antibacterial and antibiofilm drugs for clinical usage. Polyphenols represent a class of plant natural products which are important in plant defense against microbial pathogens. The main focus of the review is on the antibiofilm activities of phenolic compounds against bacteria which play an essential role in medical device biofilm-associated infections. The other, not negligible part of the review is devoted to polyphenols' activity against bacterial agents that cause dental caries and periodontal disease.

Resveratrol and para-coumarate serve as ring precursors for coenzyme Q biosynthesis.

Coenzyme Q (Q or ubiquinone) is a redox-active polyisoprenylated benzoquinone lipid essential for electron and proton transport in the mitochondrial respiratory chain. The aromatic ring 4-hydroxybenzoic acid (4HB) is commonly depicted as the sole aromatic ring precursor in Q biosynthesis despite the recent finding that para-aminobenzoic acid (pABA) also serves as a ring precursor in Saccharomyces cerevisiae Q biosynthesis. In this study, we employed aromatic (13)C6-ring-labeled compounds including (13)C6-4HB, (13)C6-pABA, (13)C6-resveratrol, and (13)C6-coumarate to investigate the role of these small molecules as aromatic ring precursors in Q biosynthesis in Escherichia coli, S. cerevisiae, and human and mouse cells. In contrast to S. cerevisiae, neither E. coli nor the mammalian cells tested were able to form (13)C6-Q when cultured in the presence of (13)C6-pABA. However, E. coli cells treated with (13)C6-pABA generated (13)C6-ring-labeled forms of 3-octaprenyl-4-aminobenzoic acid, 2-octaprenyl-aniline, and 3-octaprenyl-2-aminophenol, suggesting UbiA, UbiD, UbiX, and UbiI are capable of using pABA or pABA-derived intermediates as substrates. E. coli, S. cerevisiae, and human and mouse cells cultured in the presence of (13)C6-resveratrol or (13)C6-coumarate were able to synthesize (13)C6-Q. Future evaluation of the physiological and pharmacological responses to dietary polyphenols should consider their metabolism to Q.

Antifolate Activity of Plant Polyphenols against Mycobacterium tuberculosis.

With the view of exploring phytochemicals as Mycobacterium tuberculosis (Mtb) dihydrofolate reductase inhibitors, known plant polyphenols from various classes were subjected to detailed docking studies. From this in-silico screening, seven polyphenols were selected and tested against Mtb H37 Rv in whole cell assays. The phytochemicals exhibited potential activity ranging from 3 to 183 µm. These molecules were then tested against the pathogenic and human enzymes in a high-throughput microtitre assay. Epigallocatechin gallate showed the best activity and selectivity. The in-silico analysis was in agreement with the assay results. Of these 7 polyphenols, 5 exhibiting minimum inhibitory concentration values of ≤15 µm were tested for synergistic activity with first line drug Ethambutol and second line folate inhibitor para-amino salicylic acid. Epigallocatechin gallate, Magnolol and Bakuchiol exhibited moderate synergistic association by lowering the minimum inhibitory concentration of these drugs. These simple phytochemicals could hence be considered as leads for further studies, or for preparation of semi-synthetic derivatives to be used in combination therapy, for increased anti-tuberculosis activity after validation in-vivo.

Effects of supplementation with acai (Euterpe oleracea Mart.) berry-based juice blend on the blood antioxidant defence capacity and lipid profile in junior hurdlers. A pilot study.

The purpose of this pilot study was to examine whether regular consumption of an acai berry-based juice blend would affect sprint performance and improve blood antioxidant status and lipid profile in junior athletes. Seven junior hurdlers (17.5±1.2 years) taking part in a pre-season conditioning camp were supplemented once a day, for six weeks, with 100 ml of the juice blend. At the start and the end of the camp the athletes performed a 300-m sprint running test on an outdoor track. Blood samples were taken before and immediately after the test and after 1 h of recovery. Blood antioxidant status was evaluated based on activities of antioxidant enzymes (superoxide dismutase [SOD], catalase [CAT], glutathione peroxidase [GSH-Px], glutathione reductase [GR]), concentrations of non-enzymatic antioxidants (reduced glutathione [GSH], uric acid), total plasma polyphenols, ferric reducing ability of plasma (FRAP), thiobarbituric acid reactive substances (TBARS) and activities of creatine kinase (CK) and lactate dehydrogenase (LDH) as muscle damage markers. In order to evaluate potential health benefits of the acai berry, the post-treatment changes in lipid profile parameters (triglycerides, cholesterol and its fractions) were analysed. Six weeks' consumption of acai berry-based juice blend had no effect on sprint performance, but it led to a marked increase in the total antioxidant capacity of plasma, attenuation of the exercise-induced muscle damage, and a substantial improvement of serum lipid profile. These findings strongly support the view of the health benefits of supplementation with the acai berry-based juice blend, mainly attributed to its high total polyphenol content and the related high in vivo antioxidant and hypocholesterolaemic activities of this supplement.