Correlation of total phenol content with antibacterial activity of unripe fruit peel fraction of kayu banana (Musa paradisiaca L. var. Kayu)

Gastrointestinal diseases are dangerous diseases and can cause death. Two of the causes of bacterial infection are S. aureus and E. coli. Enterotoxin is the main cause of food poisoning accompanied by diarrhea. The unripe fruit peel of the kayu banana is a medicine commonly used empirically in Senduro village, Lumajang, East Java, to treat diarrhea. This study aimed to determine the difference in antibacterial activity in the fraction of unripe fruit peels of kayu banana. The liquid dilution method is used to measure Minimum Inhibitory Concentration (MIC) at a Concentration of 1mg/ml and MBC (Minimum Bactericide Concentration) at a Concentration of 1mg/ml, and the disc diffusion method is used to measure the inhibitory zone and Total phenol content was measured using a spectrophotometer instrument. The ethyl acetate fraction has the most optimal antibacterial activity with an inhibitory zone of 19 mm in E. coli and 9 mm in S. aureus, a MIC of 1mg/ml of ∆OD (Optical Density) -0.295 in E. coli and ∆OD -0.931 in S. aureus and no bacterial growth in the MBC with a total phenol value of 270.88 mg of gallic acid equivalent per gram of fraction. The results of Pearson analysis show a correlation between total phenol content and antibacterial activity, which is indicated by an R-value close to 1, for E. coli, it has a moderate correlation, and for S. aureus, it has a very strong correlation. The unripe fruit peel fraction of kayu banana has different antibacterial activity and can inhibit the growth of S. aureus and E. coli. The findings of this study show that the ethyl acetate fraction has the highest phenol content and a strong antibacterial activity category, so the unripe fruit peel of kayu bananas can be developed into antibacterial drugs.