The Effect of Polyphenol Extracts from Eucalyptus Spp. against Pathogenic Bacteria with Antioxidant Activities

Abstract

Eucalyptus spp. have been used as a traditionally for the treatment of disorders such as diarrhea, peptic ulcer, hemorrhoid, inflammation, pulmonary and skin diseases. The aim of this study was to determine of  total phenolic content, antibacterial and antioxidant activities of polyphenol extracts from  plant leaves. Well diffusion assay was used to test antibacterial activity against Staphylococcus aureus, Escherichia coli, klebsiella pneumonia and Pseudomonas aeruginosa. DPPH radical scavenging activity assay was used to evaluate their antioxidant activity. FTIR and HPLC techniques were used to identify polyphenol compounds in extracts. Total phenol content of plant leaves extract were at 40.07, 50.30 and 82.64 mg of GAE/g in (0.1, 0.5 and 1) mg/ml of extracts. Polyphenol extract from plant leaves exhibited significant at P value < 0.05 inhibition against pathogenic bacteria. Polyphenol extract of the study have high level 75.84% with significant at P value < 0.05 of antioxidant activities compared with ascorbic acid at 97.32% at 0.12 mg/ml of concentration.  FTIR analysis of polyphenol fraction  of the plant identified functional groups such a phenolic– OH group stretching, C-H stretching, Aromatic C=C and Aliphatic C–O in this fraction. HPLC results of extract showed specific phenolic compounds. It could be concluded that the polyphenol of the part of the plant  had a good antibacterial and antioxidant effects.