Phytochemical Profiling Using GC-MS, Antioxidant and Antidepressant Properties of Methanolic Leaf Extract of Clerodendrum polycephalum Baker in Swiss Mice

Background: Clerodendrum polycephalum Baker is used by the traditional people in southwest Nigeria for arresting bleeding from cuts and treating bacterial infections especially wound infection without scientific proof of its efficacy. The plant was investigated in animal models for its antidepressant activity in Swiss mice.

Methods: The GC-MS, phytochemical analyses, antioxidant activities, tail suspension test, forced swimming test and oxidative stress parameters were determined using standard procedures.

Results: A total of 27 compounds were identified consisting of five prominent compounds and 22 minor compounds. The five prominent compounds constitute 63.99% of the Clerodendrum polycephalum Baker plant. The five major compounds and their percentage abundance are: Bicyclo[3.1.1]heptane, 2,6,6-trime thyl- (21.36%), Squalene (18.69%), Neophytadiene (10.71%), 2-Tridecanol (6.66%) and 2-Dodecanol (6.57%). The phytochemicals present in the methanolic leaf extract of C polycephalum are: flavonoids, steroid, tannins, saponins, anthraquinones, alkaloids, terpenoids, anthocyanin, phenolic compounds and carbohydrate The extract has the ability to scavenge DPPH activity and it contains other components like: total proanthocyanidine (1.369±0.184), flavonoids (2.4%), β-Carotene (0.1336± 0.45 µg) and lycopene (0.0340±0.053µg/g). The antidepressant result showed robust and dose-dependent antidepressant-like activity of Clerodendrum polycephalum Baker. There are statistically significant (P<0.0001) reductions in the duration of immobility time both in the tail suspension and forced swimming test. Clerodendrum polycephalum extract produced significant (P<0.0001-0.0044) increase in total protein of the plasma, liver and kidney homogenate of the treated groups (Group C, D and E) compared to the untreated mice in group B. The level of antioxidant parameter such as catalase, and superoxide dismutase were significant increased (P<0.0001) and MDA values significantly reduce (P<0.0001-0.0014) in the treated groups administered with the extract and imipramine compared to the untreated mice in group B.

Conclusion: The results show that methanolic leaf extract of the Clerodendrum polycephalum Baker has potential antioxidant and antidepressant activities and further studies should be conducted to identify, isolate and evaluate its potential active compound responsible for such effect.