Abstract
- Background
The açaí berry, harvested from the açaí palm (Euterpe oleracea Mart.), has a rich tradition of consumption in Brazil and has rapidly gained international prominence as a functional food and dietary ingredient. Despite its widespread popularity, comprehensive clinical data regarding its human health effects and the systemic bioavailability of its bioactive phytochemicals remain limited. Anthocyanins—predominantly cyanidin glycosides—are key antioxidant constituents within açaí, yet their pharmacokinetic profiles and systemic physiological impacts following acute human ingestion require rigorous evaluation. This randomized, acute four-way crossover clinical trial was designed to evaluate the comparative pharmacokinetics of anthocyanin absorption and excretion, alongside systemic antioxidant modulations, following the consumption of standardized açaí pulp and clarified açaí juice relative to appropriate control foods.
- Methods
A rigorous acute four-way crossover clinical trial design was implemented involving twelve healthy human volunteers. Following an overnight fast and a strictly enforced washout phase, participants consumed standardized treatments dosed at 7 mL per kilogram of body weight, comparing açaí pulp and clarified açaí juice against applesauce and a non-antioxidant control beverage. Serial blood plasma samples were collected repeatedly over a 12-hour post-prandial period, and urine was systematically sampled over a 24-hour interval. Noncompartmental pharmacokinetic analysis quantified total anthocyanins (expressed as cyanidin-3-$O$-glucoside equivalents) to determine maximum plasma concentration ($C_{\max}$), time to maximum concentration ($t_{\max}$), and the area under the curve ($\text{AUC}_{\text{last}}$). Nonlinear mixed-effect modeling assessed the influence of dose volume on relative oral bioavailability. Systemic redox status was evaluated via plasma antioxidant capacity assays, urinary antioxidant capacity, cellular generation of reactive oxygen species, and circulating plasma uric acid concentrations.
- Results
Pharmacokinetic profiling of total anthocyanins demonstrated quantifiable systemic absorption following açaí consumption, revealing $C_{\max}$ values of 2321 ng/L at a $t_{\max}$ of 2.2 hours for açaí pulp, and 1138 ng/L at a $t_{\max}$ of 2.0 hours for clarified açaí juice. Corresponding $\text{AUC}_{\text{last}}$ values reached 8568 ng·h/L for the pulp and 3314 ng·h/L for the juice, highlighting enhanced systemic exposure from the whole pulp matrix. Nonlinear mixed-effect modeling identified dose volume as a significant predictor of relative oral bioavailability, exhibiting a negative nonlinear relationship for both açaí presentations. Furthermore, plasma antioxidant capacity was significantly elevated following the ingestion of açaí pulp and applesauce, with individual participants exhibiting dramatic increases in plasma antioxidant capacity of up to 3-fold for açaí pulp and 2.3-fold for açaí juice. However, treatments induced no statistically significant alterations in urinary antioxidant capacity, leukocyte generation of reactive oxygen species, or circulating plasma uric acid concentrations.
- Conclusions
Acute human consumption of açaí pulp and juice results in measurable systemic absorption and bioavailability of anthocyanins, accompanied by significant enhancements in plasma antioxidant capacity. The whole pulp matrix provides superior pharmacokinetic exposure compared to clarified juice, confirming the physiological efficacy and antioxidant potential of açaí-derived phytochemicals in human subjects.
https://pubmed.ncbi.nlm.nih.gov/18693743/