Isolation and evaluation of significant antibacterial fraction of methanol and its derived fractions from the leaves extract of Zygophyllum simplex

Food poisoning related to bacterial contamination is the most common disease and cause of death nowadays in developing countries. There are many plants that have made a revolution in the field of medicine. Zygophyllum simplex (Z. simplex) is a plant that is native to Oman and it has been used since ancient times as a cure for human infectious diseases. The purpose of this study is to prepare different polarities containing plant crude extracts and evaluate their antibacterial behavior using the agar gel diffusion technique. In order to arrange their extracts via the Soxhlet extraction technique and solvent-solvent fraction technique, multi-polar solvents were used. With minor modification, the antimicrobial behaviors of the multi-polar extracts taken out were calculated by the agar gel diffusion technique. The antimicrobial action as a zone of inhibition of six different extracts at four concentrations was completed against two Gram-negative: Escherichia coli (E. coli, Code No. 683) and Klebsiella Pneumonia (K. pneumonia, Code No. 684), and three Gram-positive bacteria: Staphylococcus aureus (S. aureus, Code No. 659), Streptococcus pseudopneumonia (S. pseudopneumonia, Code No. 685), Bacillus pumilus (B. pumilus, Code No. 690). Different crude extracts showed antimicrobial activity against Gram (+ and -) bacteria at different concentrations. All extracts at different concentrations showed moderate to substantial activity against the bacterial strains of Grams (+and-) except methanol against B. pumilus. All various polarities crude extracts, ethyl acetate, DCM (dichloromethane), and water extracts at different concentrations showed the maximum activity against E coli within the range of 8–13.5 mm. The highest inhibition zone was found in DCM extract and the lowest antimicrobial activity was found in the hexane extract against different bacterial strains. So the order of DCM > butanol > water > methanol > hexane extracts preceded it. To isolate pure compounds by using column chromatography, the highest antibacterial activity DCM crude extract was chosen. The eluents were collected in a series of test tubes and a total of eight fractions were prepared based on the thin layer chromatography behavior. Similarly, the isolated eight fractions from the column were used to determine their antibacterial activity by the same agar diffusion method. The results showed that fractions number 2 and 4 gave the highest activity among the other fractions. In conclusion, the DCM extract as well as fraction numbers 2 and 4 exhibited promising activities against Gram-negative bacterial strains; therefore, the DCM extract, fraction 2, and fraction 4 could be used for the treatment of various human infectious diseases as natural antibiotics.