Valorization of Philippine pili (Canarium ovatum var. Mayon) leaves and exocarp as functional herbal teas: Characterization, bioefficacy evaluation, safety assessment and sensory evaluation

The pili (Canarium ovatum var. Mayon) tree, particularly its leaves and exocarp, presents untapped potential as a sustainable source of bioactive compounds. While the nut is widely utilized for food and oil production, the leaves and exocarp are often discarded and unexplored despite being rich in secondary metabolites. This study aimed to evaluate the potential of pili leaves and exocarp as functional herbal tea ingredients. Five formulations with varying proportions of leaves and exocarp were subjected to phytochemical characterization, bioefficacy evaluation, safety assessment, and sensory acceptability. The phytochemical analysis revealed the presence of phenolics, flavonoids, saponins, and glycosides across all formulations, with Formulation 5 consistently exhibiting the highest concentration of these phytochemicals. Results showed that all formulations exhibited notable bioefficacy and potential as functional beverages. DPPH radical scavenging activity ranged from 92.36% to 94.53%, while FRAP antioxidant activity ranged from 70.25% to 92.15. Alpha-glucosidase inhibition ranged from 16.87% to 43.94%, lipase inhibition from 10.17% to 15.40%, and ACE inhibition from 30.22% to 67.83%, with formulations containing higher leaf proportions generally showing stronger enzyme inhibitory activities. Safety assessment, including microbial and heavy metal analyses, confirmed that all formulations met the acceptable safety standards of FDA. In sensory evaluation, Formulation 2 showed the highest overall acceptability score (7.22 ± 0.97), indicating that blending pili leaves and exocarp improved sensory quality. These findings support the potential of pili leaves and exocarp as safe, acceptable, and functional herbal tea ingredients.