Phospholipase A2 Inhibition and Antiinflammatory Activity of F4 Fraction of Total Ethereal Leaf Extract of Annona senegalensis Pers. (Annonaceae)

Annona senegalensis Pers. (ANNONACEAE) is a plant which is used in african traditional medicine for the treatment of various diseases. This study aimed to investigate the analgesic and anti-inflammatory activity of total ethereal leaf extract fractions of A. senegalensis. Compounds of methanolic fractions of ethereal leaf extract of A. senegalensis were separated by gel sephadex chromatography, in five fractions (F1, F2, F3, F4, F5). Experiments were performed in acetic acid-induced contortions in mice, carrageenan rat paw edema and phospholipase A2 inhibitory test. The methanolic fraction of total ethereal leaf extract (10 mg/kg, per os) significantly prevented the carrageenan inflammatory edema. The variation of edema is 22.31±3.35 %, 49.66±13.50 %, 52.10±10.02 % respectively at T1h, T3h and T5h. The increased edema after oral administration of F4 fraction administered at 300 µg/kg and 1 mg/kg per os is respectively 52.77±7.36 % and 33.81±6.94 %. The variation of edema in betamethasone group (1 mg/kg, per os) is 23.46±3.99 %. F4 fraction at 300 µg/kg, significantly inhibited 16.39 % of phospholipase A2 enzyme activity. F4 fraction (300 µg/kg, per os) also significantly prevented acetic acid-induced pain in mice. The number of abdominal contortions is 21 versus 72 in control group. F4 fraction compounds have a powerful analgesic and anti-inflammatory activity that involves phospholipase A2 inhibition, comparable to betamethasone profile on pain and inflammation.

In vitro Antimicrobial Activity of Crude Tannins Isolated from the Stem Bark of Annona senegalensis.

The aim of this study is to determine the antimicrobial activity of crude tannins from the stem bark of Annona senegalensis on some diarrhoea causing bacteria strains. The study was carried out in the laboratory of Biochemistry department, Modibbo Adama University of Technology, Yola, Adamawa State, Nigeria, between July and October, 2013. The antimicrobial activity was carried out using agar disc diffusion method. The phytochemical analysis revealed the presence of tannins, alkaloids, saponins, cardiac glycosides, steroids, tarpenoids and phenols. Quantitatively, crude tannins of 170.16mg were found to be present in 500mg of the extract which makes up a percentage composition of 34.03%. The extracted crude tannins were used to test for antimicrobial effect against Escherichia coli, Salmonella typhi, and Staphylococcus aureus and were only effective on Staphylococcus aureus with 19mm as the inhibition zone using the concentration of 100mg/ml. The Minimum Inhibitory Concentration (MIC) of the extracted crude tannins was observed at 12.5mg/ml on Staphylococcus aureus. This suggests that the isolated crude tannins have an antistaphylococci activity and can be used to treat infections caused by the organism.

Kaurenoic Acid Isolated from the Root Bark of Annona senegalensis Induces Cytotoxic and Antiproliferative Effects against PANC-1 and HeLa cells.

Aims: Cancer is one of the leading causes of death worldwide with an estimated 6.7 million deaths and 24.6 million people living with cancer in 2002. Presently, there is a global increase in prevalence, mortality and health burden of various malignancies. World Health Organization (WHO) report projected that cancer prevalence rates could further increase by 50% to 15 million new cases in the year 2020. The bioactivity guided isolation of the bioactive constituent and its characterization, responsible for the anticonvulsant effects of the root bark extract of A. senegalensis yielded kaur-16-en-19-oic acid (KA). Therefore, the aim of this study was to evaluate the anti-proliferative activity of kaurenoic acid from A. senegalensis on selected cancer cell lines. Study Design: The study was designed to ascertain the antiproliferative and cytotoxic effects of kaurenoic acid, a diterpenoid isolated from the root bark of Nigerian Annona senegalensis (Annonaceae). Place and Duration of Study: Department of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, University of Nigeria, Nsukka, Nigeria, between October 2010 and June, 2012. Methodology: Human embryonic kidney cells expressing SV40 Large T-antigen (293 T), Pancreatic tumour (PANC-1) and Henrietta Lacks’ cervical (HeLa) cell lines were used in the study using standard MTT, 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazoliumbromide, assay method. Results: Kaurenoic acid (KA) exhibited cytotoxic effects against the cells with estimated IC50 values of 0.93, 0.74 and 0.52 M concentrations for 293 T, HeLa and PANC-1 cells respectively. This is an indication of the possible potentials of KA in the treatment of cervical and pancreatic cancers. Conclusions: Kaurenoic acid (KA), a diterpenoid, possesses antiproliferative effect against HeLa and PANC-1 cell lines, and could be the anticancer constituent in the root bark extract of A. senegalensis with potentials as a lead in the chemical synthesis of standard anti cancer agents.