Effect of microencapsulation and freeze-drying on the functional properties of Spondia mombin stem extract used in ethno-medical management of benign prostrate hyperplasia

Introduction: Different techniques have been used to improve the stability and bioavailability of biomaterials. This study aims to modify the crude stem extract of Spondia mombin used in ethno-medical management of benign prostrate hyperplasia (BPH).

Methods: Spondia mombin stem extract was modified by microencapsulation and freeze drying, and characterised using scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and Fourier transform infrared spectroscopy (FTIR) analysis. The extracts were evaluated for physicochemical properties using micromeritic determination and dissolution studies, and for in vivo pharmacological properties using prostate-specific antigen (PSA), serum testosterone, and prostate index (PI) analysis on male Wister rats.

Results: SEM analysis showed a larger particle size of 50–80 µm for microencapsulated extract compared to >50 µm of crude extract. FT-IR and EDX analysis revealed relatively unchanged spectrum and additional molecules respectively in the modified extract compared to the crude extract. These results are suggestive of chemical compatibility and physical agglomeration in the interaction of the crude extract with microencapsulation excipients. Dissolution studies revealed steady release of extract from the microencapsulated form over 60 minutes, and > 9.76 times increase in peak release compared to release from the crude extract. The micromeritic studies showed improved flow properties for the microencapsulated extract with angle of repose < 27.9°, Hausner’s ratio < 1.06, and compressibility index < 6.06 %. The microencapsulated extract showed peak reduction in PSA at 100 mg / kg, compared to peak reduction of PSA of crude extract at 400 mg / kg. Serum testosterone levels decreased significantly in the microencapsulated extract.

Conclusion: Microencapsulation improved the flow and dissolution properties of Spondia mombin extract, and retained its pharmacological activities. There is a need to conduct human clinical trials to further explore the potentials of this microencapsulated