The antimicrobial activity of coffea arabica, coffea canephora, and coffea liberica aqueous extracts on multiple drug resistant pathogens and their cytotoxic effect on human cancer cell lines and normal human fibroblast

Antibiotics have been indispensable to humanity as treatments for numerous infectious diseases, and as a means for protection against further infections. However, the misuse of antibiotics has led to the rapid emergence and positive selection for multiple drug resistant microbial strains that are resistant to most conventional antibiotics. Cancer is a growing problem, as the cure for most cancers is far from being realized. Recent studies have shown that coffee extracts have antimicrobial effects against bacterial pathogens and are toxic against cancer cells. The research aimed to determine the antimicrobial activity of aqueous extracts of Coffea arabica, Coffea canephora, and Coffea liberica against clinical isolates of multiple-drug resistant bacteria, namely: carbapenemase-producing Klebsiella pneumoniae, extended spectrum β-lactamase positive Escherichia coli, β-lactamase producing Acinetobacter baumannii, extended spectrum β-lactamase positive Klebsiella pneumoniae, Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus using the disk diffusion assay, and the cytotoxicity of the extracts against the normal human dermal fibroblast HDFn, human colon cell line HT-29, human breast cancer cell line MCF-7, and human monocytic leukemia cell line THP-1 using the PrestoBlue® Resazurin Cell Viability Assay The results showed that none of the coffee extracts inhibited the growth of the multiple-drug resistant bacteria strains tested in the study. Based on the guidelines set by the US National Cancer Institue, the aqueous coffee extracts from the three coffee species used were found to be highly cytotoxic to all the cancer cell lines used with the IC50 \u3c 20μg/ml. Moreover, extracts from Coffea arabica and Coffea canephora were found to be noncytotoxic to HDFn therefore showing its potential for further development of cancer treatment. Coffea liberica was found to be cytotoxic making the study for its safety usage needed