Antimicrobial and Biochemical Properties of Three Nigerian food Spices; Piper guineense, Xylopia aethiopica and Monodora myristica

Abstract

Piper guineense, Xylopiaaethiopica and Monodoramyristica seeds are among the plant parts commonly used as spices and studied evaluating the proximate composition while mineral parameters were evaluated using Atomic Absorption Spectrophotometer (AAS) methods. Antibacterial activity was assessed using the agar well diffusion method while gas chromatography and mass spectrometry were used for the phytochemical analysis. Results of the study showed that X. aethiopica seeds were high in percentage moisture content (9.60%), crude fiber (9.97%) and crude protein (28.67%) compare to P. guineense and M. myristica while P. guineense was high in percentage lipid (26.00%) and carbohydrate (63.05%). The differences in the moisture content, lipid, crude fibre, crude protein and carbohydrate were statistically significant (P<0-05). M. myristica seeds had a higher amount of copper (49.885mg/kg), potassium (2.835%), calcium (1.570%) and sodium (1.730%) than P. guineense and X. aethiopica seeds, while X. aethiopica seeds had a higher amount of zinc (33.675mg/kg) than M. myristica and P.guineense seeds. P. guineense seeds had a higher amount of iron (655.455mg/kg) than M. myristica and X.aethiopica seeds. The differences in the calcium, potassium, sodium, copper, iron, and zinc were statistically significant (P<0.05). Ethanol extract of X. aethiopica showed higher inhibitory effect (P<0.05) against Staphylococcus aureus with MIC of 3.125mg/ml and MBC 25mg/ml. Among the thirty five compounds detected in piper guineense, thirty two compounds in xylopiaaethiopica and thirty one compounds in Monodoramyristica, the common ones were Lauric anhydride, Dodecanoic acid and Octadecanoic acid. The present study had pontentials for microbial control with Xylopiaaethiopica showing the most inhibitory action.