Molecular Confirmation on the Synonymy of Phaeanthusebracteolatusand P Ophthalmicusincluding Biological Activities of Its Phytochemical Constituent

The genus Phaeanthus Hook.f and Thomson of the family Annonaceae is a medicinal plant essentially characterized by inner petals that are longer than outer petals, numerous carpels and stamens, and monocarpous fruits. Previous studies have recognized Phaeanthus ebracteolatus as a synonym of P. ophthalmicus based on the morphological examination of limited herbarium specimens. In order to determine the validity of the finding, this study aims to verify the synonymy of P. ebracteolatusand P. ophthalmicus using combined matK and rbcL dataset, as well as computing its sequence divergence; and, to further explore the phytochemical and biochemical components of the plant.Collected plant samples were subjected to morphological characterization followed by molecular analysis through DNA extraction, amplification, purification, sequencing, sequence analysis and data analysis. The crude leaf extracts were subjected to phytochemical screening by thin layer chromatography and three colorimetric assays such as α-glucosidase inhibition, anti-tyrosinase and anti-Staphylococcus. This study confirms that the two Phaeanthus species are conspecific using combined matK and rbcL dataset which is strongly supported and computed sequence divergence which includes 5 bp (0.81%) and 3 bp (0.41%) in matK and rbcL regions, respectively. Overlapping morphological characters such as axillary inflorescence, valvate inner and outer petals, truncate stamens, club-shaped carpels, and globose monocarps also support the finding. The crude leaf extract yields positive to different antioxidant constituents and demonstrated a high potency in α-glucosidase inhibition. The study validated the synonymy of P. ebracteolatus and P. ophthalmicus using sequences and morphology, with P. ophthalmicus being acknowledged as its correct name. Furthermore, the plant extracts proved to be efficient as an α-glucosidase inhibitor