Bioactivity of Backhousia citriodora: antibacterial and antifungal activity

Backhousia citriodora products are used as bushfoods and flavorings and by the aromatherapy industry. The antimicrobial activity of 4 samples of B. citriodora oil, leaf paste, commercial tea (0.2 and 0.02 g/mL), and hydrosol (aqueous distillate) were tested against 13 bacteria and 8 fungi. Little or no activity was found to be associated with the leaf tea and hydrosol, respectively. Leaf paste displayed antimicrobial activity against 7 bacteria including Clostridium perfringens, Pseudomonas aeruginosa, and a hospital isolate of methicillin resistant Staphylococcus aureus (MRSA). The 4 essential oils were found to be effective antibacterial and antifungal agents; however, variation was apparent between oils that did not correlate with citral content. The antimicrobial activity of B. citriodoraessential oils was found to be greater than that of citral alone and often superior to Melaleuca alternifolia essential oil. B. citriodora has significant antimicrobial activity that has potential as an antiseptic or surface disinfectant or for inclusion in foods as a natural antimicrobial agent.