ANTIBACTERIAL POTENTIAL OF METHANOL EXTRACT _CURCUMA LONGA_ SEED AND PEEL

ABSTRACT The study focuses on the growing problem of bacterial resistance to antibiotics and the therapeutic potential of turmeric (Curcuma longa). Rich in bioactive compounds like curcumin, turmeric exhibits antibacterial and anticancer properties. This research aims to investigate the antibacterial effects of methanol extracts of turmeric seeds and peels.The study involved collecting turmeric samples from markets in Ado-Ekiti, which were dried, ground, and extracted using methanol. The extracts were filtered, concentrated, and stored for analysis. Six bacterial strains were tested for antibacterial activity using Mueller Hinton Agar, Kirby bauer disc diffusion method. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined using broth microdilution methods. The antimicrobial activity over time was assessed through kill kinetics. Finally, the chemical composition of the turmeric extracts was analyzed using Gas Chromatography-Mass Spectrometry (GC-MS), identifying the organic compounds based on their mass spectra and relative quantities. The study found that methanol turmeric peel (MTMP) showed antimicrobial activity against S. aureus, E.coli, and B. subtilis but not against P. aeruginosa, Klebsiella and Salmonella at zones ranging from 8mm to 14 mm. Methanol turmeric seed (MTMS) showed anti microbial activity against S. aureus,E.coli, P.aeruginosa, Klebsiella and Salmonella but not against B. Subtilis. The MIC and MBC values for both MTMS and MTMP are the same (50ug/ml) for all the tested organisms. For the time kill, the study demonstrated that MTMP and MTMS extracts possess time-dependent microbicidal activity against S. aureus and E. coli, with MTMP showing complete killing at lower MICs (40 µg/ml for S. aureus and 26 µg/ml for E. coli within 2 hours), while MTMS required a higher MIC (148 µg/ml for S. aureus and 164 µg/ml for E. coli), and both extracts necessitated longer exposure times for effective bacterial eradication compared to the rapid action of ciprofloxacin. The analysis of turmeric methanol extracts using a Varian 3800/4000 gas chromatograph mass spectrometer (GCMS) identified twenty compounds, including fatty acids (palmitic, oleic, stearic, and linoleic acids), terpenes (eugenol and linalool), and phenolic compounds (1,2-benzenedicarboxylc acid and 4-hydrobenzoic acid). Both extracts (MTMP and MTMS) contained similar compounds, with variations in their relative abundances. The research indicated that turmeric extract exhibit antimicrobial properties and comprise a range of compounds, including fatty acids and terpenes. Their significant antioxidant and antimicrobial characteristics suggest potential applications as natural preservatives in food or as complementary treatments alongside antibiotics for infections.