PHYSICOCHEMICAL CHARACTERIZATION OF HIBISCUS SABDARIFFA L.CALYX MUCILAGE FOR PHARMACEUTICAL APPLICATION

Abstract

The pharmaceutical formulation industry is increasingly turning to excipients sourced from edible natural products,
as these have proven effective in stabilizing, enhancing the solubility, absorption, and bioavailability of Active
Pharmaceutical Ingredients (APIs). This study aimed to evaluate the physicochemical properties of mucilage
extracted from red and white calyces of Hibiscus sabdariffa Linn for potential pharmaceutical use. The mucilage
was extracted from red and white calyces of Hibiscus sabdariffa, and the yield (%) was determined. Subsequent
evaluations included the determination of various physicochemical properties, such as particle density, flow
properties, swelling capacity, moisture content, moisture sorption capacity, and pH. Other analyses such as FTIR,
SEM, and XRD were carried out on both samples. Yields of 10.87% (red) and 9.66% (white) mucilage were
obtained. Both samples exhibited acceptable flow properties. The swelling capacity reached 280% and 260% after
24 h and moisture contents were 0.29% and 0.19% for the red and white samples, respectively. The pH
measurements were 4.01 (red) and 3.81 (white). FTIR spectroscopy identified functional groups characteristic of
polysaccharides. Differences in the 1700–1500 cm⁻¹ range suggested variations in protein or secondary metabolite
interactions. SEM analysis revealed that the red sample had a more porous, fibrous texture, while the white sample
appeared denser and more compact. XRD analysis confirmed the amorphous nature of both samples. The
physicochemical properties of both mucilage especially high swelling capacity of both samples highlight their
potential as suitable disintegrants for pharmaceutical applications. Further studies are recommended to evaluate the
functional applications of the mucilage because of their good hydration and moisture sorption properties.