AN EFFICIENT DETERMINATION OF PHENOLIC COMPOUNDS BY HPLC-DAD AND THEIR BIOACTIVITY ASSAY FROM AERIAL PARTS OF EUCALYPTUS TERETICORNIS

Current study is based on the extraction of free and bound phenolic compounds (PC) in aerial parts i.e., stem, skin, leaves, and seeds of E. tereticornis (local name: Sufeda) plant. The two different extraction procedures (Sonication and ultrasonic assisted base hydrolysis) and their antimicrobial activity against two bacteria i.e. Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were analyzed. The RP-HPLC-DAD was applied for separation and detection of phenolic compounds (PC). The HPLC profiling revealed the existence of 13 PC in which 11 were phenolic acids and 2 aldehydes derivatives, while bound PC possessing greater fraction than free ones. The results from ultrasonic assisted extraction revealed the gallic (23.47 mg/g), p-coumaric (16.66 mg/g), p-hyroxybenzoic (11.03 mg/g) and ferulic (8.71 mg/g) acids. While Sonication extraction method shows the chlorogenic (8.14 mg/g), vanillic (11.47 mg/g), sinapic (4.68 mg/g) and caffeic (5.38 mg/g) acids as main constituents in skin, seed, stem and leaves respectively. Four PC were identified as bound phenolic acids i.e., p-coumaric, cinnamic, naringenin and catechin, while other of the compounds were found in both extracts. The free radical scavenging activity (RSA) and total phenolic contents (TPC) were present in greater amounts in seed (164.61 Mm/g) and skin (118.96 Mm/g) while total flavonoids and total tannins were higher in stem (42.77 Mm/g) and (28.13 Mm/g), respectively. E. Tereticornis leaves, stem, seeds and skin extracts were observed to be highly effective for E coli and S. aureus. The antimicrobial action of E. Tereticornis extracts was higher against S. aureus (MIC value 125 mu g/mL) than E. coli (MIC value 250 mu g/mL). It is concluded that the potential health benefits of E. tereticornis highlight its significance in the field of natural product chemistry and pharmacology.