Traditional Aqueous and Ethanol Maceration of Hamelia patens Leaves: A Phytochemical and Pharmacological Exploration.

Background: Hamelia patens Jacq., commonly referred to as firebush, is a tropical shrub belonging to the Rubiaceae family. It has been traditionally employed in various ethnomedical practices to address ailments such as dermatological infections, inflammatory conditions, and gastrointestinal disturbances. These therapeutic applications are attributed to its diverse array of bioactive phytoconstituents, including alkaloids, flavonoids, and phenolic compounds. Despite extensive studies on organic solvent extracts, there remains a paucity of data concerning the efficacy and phytochemical composition of traditional aqueous extracts.

Objective: This investigation aims to delineate the maceration-based extraction methodologies utilizing aqueous and ethanol solvents for H. patens leaves and to underscore the significance of each method in isolating pharmacologically active compounds.

Materials and methods: Freshly harvested H. patens leaves underwent thorough washing and were subsequently dried either by air in a shaded, well-ventilated environment or using an oven maintained at 40°C-50°C to preserve thermolabile constituents. The desiccated leaves were then pulverized into a coarse powder. For extraction, 5 g of the coarsely powdered material were subjected to maceration with 100 mL of distilled water and 50 mL of ethanol (70%-95%) for a duration of 24-72 h at ambient temperature, with intermittent agitation to facilitate solvent penetration. Postmaceration, the mixtures were filtered to obtain the respective aqueous and ethanol extracts. Comprehensive phytochemical screening was conducted to detect the presence of alkaloids, flavonoids, tannins, saponins, phenolics, glycosides, triterpenoids, phytosterols, and carbohydrates.

Results: Phytochemical analyses revealed that the aqueous extract evaluated positive for alkaloids, saponins, phytosterols, phenols, flavonoids, carbohydrates, glycosides, and triterpenoids, while tannins were absent. Conversely, the ethanol extract demonstrated the presence of phytosterols, phenols, flavonoids, carbohydrates, glycosides, and triterpenoids but evaluated negative for tannins, alkaloids, and saponins. These findings suggest that solvent polarity plays a pivotal role in the selective extraction of phytochemicals, with aqueous extraction favoring polar compounds and ethanol extraction being more efficacious for semi-polar constituents.

Conclusion: Maceration employing aqueous and ethanol solvents effectively isolates distinct profiles of bioactive compounds from H. patens leaves. The aqueous extract, enriched with polar phytochemicals, aligns with traditional medicinal preparations, whereas the ethanol extract, containing a broader spectrum of semi-polar compounds, holds considerable promise for pharmaceutical applications.