Studies on Quantitative Phytochemical Profile, GC-MS Analysis and In-vitro Antioxidant Properties of the Stem Bark of Dennettia tripetala BAK. F. (Annonaceae)

Dennettia tripetala also known as pepper fruit, widely consumed in West Africa, has been used in traditional medicine for the management of inflammations, diabetes, cough, fever, nausea, and even as an antioxidant agent. Plants have played a significant role in preventing degenerative diseases and maintaining good health. This study aims to evaluate the chemical profile and antioxidant properties of the methanol extract of the stem bark of Dennettia tripetala. The stem bark was collected, air-dried, and extracted with 70% methanol. Quantitative phytochemical screening was performed to determine the concentrations of tannins, phenolics, alkaloids, flavonoids, saponins, and terpenoids using in vitro techniques. Antioxidant activity was evaluated using ferric-reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, and nitric oxide (NO) scavenging assays and determination of total phenolic content. Gas Chromatography-Mass Spectrometry (GC-MS) analysis identified the chemical constituents of the extract. The GC-MS analysis identified ten bioactive compounds, such as eugenol, caryophyllene, naphthalene, and trimethyl arsenate, which possess therapeutic properties including anti-inflammatory and anticancer effects. The extract showed a high concentration of flavonoids (241.4 µg QE/g) and alkaloids (19.5% w/w), contributing to its biological usage. In the DPPH assay, the dichloromethane fraction had the highest radical-scavenging activity with 56.4% inhibition, while the nitric oxide (NO) scavenging test showed 80.8% inhibition in the same fraction, confirming its strong antioxidant capacity. The FRAP assay demonstrated the extract’s ability to reduce ferric ions efficiently, complementing these findings. The IC50 values confirmed the potency of the extract as an antioxidant agent, with the methanol extract at 0.03187 µM and the dichloromethane fraction showing the best performance at 0.02021 µM. These results back up the traditional use of D. tripetala in managing oxidative stress-related ailments, suggesting that its bioactive compounds have potential pharmaceutical applications.