The chemical composition of the leave extracts of Phyllanthus amarus (Schum and Thonn) of the family Euphorbiaceae from Nigeria was analyzed by GC-MS. The extracts were also examined for their potential to inhibit the growth of clinical isolates following standard procedure. The major compounds identified in the hexane extract are a flavonoid, flavone 4',5,7-triethoxy-3,3',6-trimethoxy (20.23%) and a triterpenoid 17-(1,5-Dimethylhexyl)-6-hydroxy-5-methylestr-9-en-3-yl acetate (19.02%) while bufalin (18.71%) and tetratetracontane (12.91%) were the major compounds detected in the methanol extract. Steroidal triterpenoids are the major compounds present in the extracts as it accounted for 47% of the total detectable content in the hexane extract and 52% in the methanol extract. The steroidal triterpenoids which exist primarily as acetate in the hexane extract include cycloeucalenyl acetate, ergosta-5,7,22-trien-3-ol acetate, macdougallin, 17-(1,5-Dimethylhexyl)-6-hydroxy-5-methylestr-9-en-3-yl acetate, stigmasterol and β-sitosterol while the methanol extract contains 6,7-epoxypregn-4-ene-9,11,18-triol-3,20-dione, 11,18-diacetate, bufalin, olean-13(18)-ene, methyl ursolate, barringenol R1 and 7,8-epoxylanostan-11-ol,3-acetoxy. Hexane extract of the plant exhibited antifungal activity on Candida albicans while methanol extract revealed significant antibacterial activity on Pseudomonas aeruginosa and Staphylococcus aureus at all concentrations of the extract between 12.5 and 100 mg/mL, the activity being comparable to the standard antibacterial drug, Oxacillin. The leaves of Phyllanthus amarus is a potential source of steroidal triterpenoids which could serve as biomarker for the plant species. The extracts of the plant may also serve as a natural source of antimicrobial agents for the treatment of some microbial infections.

The phytocomponents of the leaf and root extracts of Phyllanthus amarus (Euphorbiaceae) were studied. The constituents of the leaves and roots were identified and quantified by using GC-MS. Result from the phytochemical analyses showed the presence of saponins, tannins, phenolics, anthocyanins, and glycosides in both leaves and root of the plant. Alkaloids and triterpenoids were, however only absent in the root of P. amarus but present in the leaves of the plant. Flavonoids, coumarins and steroids were absent in the leaves but present in the root part. The mean concentration of the phytochemicals investigated in leaves are 0.73±0.01%, 1.85±0.03%, 1.12±0.01%, 1.80±0.01%, 1.59±0.50%, 0.13±0.10%, and 0.86±0.01%, for saponins, tannins, phenolics, anthocyanins, alkaloids, triterpenoids, and glycosides respectively, while the mean concentration of the phytochemicals investigated in roots are 0.91±0.01%, 1.53±0.03%, 0.70±0.01%, 2.97±0.10%, 2.47±0.03%, 0.62±0.01%, 0.90±0.01% and 2.02±0.10% for saponins, tannins, phenolics, steroids, flavonoids, anthocyanins, glycosides and coumarins respectively. Furthermore, the GC-MS analysis of methanol extracts of the leaves and root of P. amarus revealed the presence of three medicinally important bioactive compounds, which are: 9-Octadecenoic acid which has percentage of abundance of 92.23% and 82.46% in leaves and roots of the plant respectively, followed by n-Hexadecanoic acid and Tetradecanoic acid with their corresponding percentage of abundance of 7.7% and 17.54% for leaves and root. These analytical results suggest the plantto possess a significant role in phyto-medicine. The importance of this plant was discussed in line with the role they play in ethnomedicinal life of the people. Keywords: Phyllanthus amarus; Phytochemicals; GC-MS; methanolic extract; Phytocomponents