Chemotyping of diverseEucalyptusspecies grown in Egypt and antioxidant and antibacterial activities of its respective essential oils

Abstract

The chemical composition of the essential oil from the leaves of Eucalyptus camaldulensis, Eucalyptus camaldulensis var. obtusa and Eucalyptus gomphocephala grown in northern Egypt was analysed by using GC-FID and GC-MS techniques. The antibacterial (agar disc diffusion and minimum inhibitory concentration methods) and antioxidant activities (2,2'-diphenypicrylhydrazyl) were examined. The main oils constituents were 1,8-cineole (21.75%), β-pinene (20.51%) and methyleugenol (6.10%) in E. camaldulensis; spathulenol (37.46%), p-cymene (17.20%) and crypton (8.88%) in E. gomphocephala; spathulenol (18.37%), p-cymene (19.38%) and crypton (16.91%) in E. camaldulensis var. obtusa. The essential oils from the leaves of Eucalyptus spp. exhibited considerable antibacterial activity against Gram-positive and Gram-negative bacteria. The values of total antioxidant activity were 70 ± 3.13%, 50 ± 3.34% and 84 ± 4.64% for E. camaldulensis, E. camaldulensis var. obtusa and E. gomphocephala, respectively. The highest antioxidant activity value of 84 ± 4.64% could be attributed to the high amount of spathulenol (37.46%).

The pharmacological and therapeutic importance of Eucalyptus species grown in Iraq

“…obtusa and Eucalyptus gomphocephala, respectively. The highest antioxidant activity value of 84 ± 4.64% could be attributed to the high amount of spathulenol (37.46%) [127].The effects of essential oil from Eucalyptus camaldulensis flowers oil on melanogenesis and the oil's antioxidant characteristics were investigated. Assays of mushroom and cellular tyrosinase activities and melanin content of mouse melanoma cells were performed spectrophotometrically, and the expression of melanogenesis-related proteins was determined by Western blotting.…”

“…The essential oils from the leaves of Eucalyptus spp. exhibited considerable antibacterial activity against Gram positive and Gram negative bacteria [127].The antimicrobial and biofilm preventing activities of the oils of Eucalyptus camaldulensis were studied in vitro and in vivo. Minimal bactericidal concentrations (MBC) of the Eucalyptus camaldulensis oils were found to be 4 and 2 mg /ml, and those of chlorhexidine (2%) were 8 and 1 mg/ml for both S. mutans and S. pyogenes respectively.…”

Effects of natural blends of garlic and eucalypt essential oils on biogas production of four fibrous feeds at short‐term of incubation in the ruminal anaerobic biosystem

“…Sealed Eppendorf tubes with aluminium sheets were used to store the oils in a refrigerator at 4 °C before further use. Analysis of both oils was performed by GC/MS in accordance with methods described previously (GO, EO).…”

Inhibition of Fusarium culmorum , Penicillium chrysogenum and Rhizoctonia solani by n‐hexane extracts of three plant species as a wood‐treated oil fungicide

“…Previously, extracts and essential oils from E. camaldulensis have been known for their remarkable antimicrobial activities (Salem et al . ; Elansary et al . ; EL‐Hefny et al .…”