Phytochemical screening and antimicrobial activity of Theobroma cacao on Staphylococcus aureus, Escherichia coli, Samonella spp and Shigella spp

Aernan Tracy Paulyn 1, Odo Joel Inya 2, * and Abah Patrick Okewu 1

1 Departments of Microbiology, University of Agriculture, Makurdi, Nigeria.
2 Department of Fisheries and Aquaculture University of Agriculture, Makurdi, Nigeria.
 
Research Article
International Journal of Scholarly Research in Chemistry and Pharmacy, 2022, 01(01), 001–010.
Article DOI: 10.56781/ijsrcp.2022.1.1.0042
Publication history: 
Received on 29 June 2022; revised on 04 August 2022; accepted on 06 August 2022
 
Abstract: 
Cocoa leaf and root were studied for medicinal prospective and the focus was to screen for phytochemicals present, Minimum Inhibitory Concentration, Minimum Bactericidal Concentration and antimicrobial activity of the cocoa root and leaf against pathogenic bacteria Staphylococcus aureus, Escherichia coli, Salmonella spp, Shigella spp. Extraction of the samples was done by filtration and concentration in water bath with methanol and aqueous as the solvents, followed by phytochemical analysis, antimicrobial activity, Minimum Inhibitory Concentration and Minimum Bactericidal Concentration. The phytochemical screening identified presence of glycosides, steroids, quinones, phenols, proteins, flavoids, tannins and alkaloids. The antimicrobial assay by agar well diffusion method of cocoa leaf and root extracts elicited ranges of zone of inhibition measured in millimetre (mm) against the selected pathogenic bacteria; Staphylococcus aureus, Escherichia coli, Salmonella spp, Shigella spp at various concentration (500Mg/ml, 250Mg/ml, 200Mg/ml, 125Mg/ml and 100Mg/ml). The aqueous leaf extract at 500Mg/ml to 100Mg/ml concentration elicited zone of inhibition ranging from 26.33±1.53 to 12.00±1.00 against S. aureus. Against E. coli the zone of inhibition ranges from 22.67±1.16 to 9.00±1.00. Similarly at 500Mg/ml to 100Mg/ml concentration the aqueous leaf elicited zone of inhibition ranging from 19.67±1.53 to 8.33±0.58 against Salmonella spp and 17.00±1.73 to 8.33±1.16 against Shigella spp. The methanolic leaf extract also elicited zone of inhibition at various concentration (500Mg/ml to 100Mg/ml) ranging from 21.33±1.53 to 11.67±1.53 against S. aureus, 26.67±2.52 to 14.33±0.58 against E. coli, 20.00±1.00 to 12.67±3.06 against Salmonella sppand 13.00±2.00 to 5.67±0.55 against shigella spp at concentration of 500Mg/ml to 100Mg/ml respectively. Lastly the root bark extract elicited zone of inhibition ranging from 22.66±2.09 to 16.00±0.00 against S. aureus, 16.33±2.31 to 10.33±1.16 against E. coli, 17.00±2.00 to 8.67±1.16 against Salmonella spp and 20.00±1.00 to 8.33±0.58 against Shigella spp at concentration of 500Mg/ml to 100Mg/ml. The MIC was at 50Mg/ml concentration for all test organisms using the three different extracts while organisms were resistant at all concentration for MBC using all extracts. It is recommended that T.cacao leaf and root are used for antibacterial agent with further purification and proper processing, it is also recommended for toxicology test to know the level of human cell tolerance.
 
Keywords: 
Antimicrobial activity; Theobroma cacao; Phytochemistry; Microorganisms; Aqueous extract; Methanolic extract
 
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