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Background: Terminalia ferdinandiana (Kakadu plum) is an endemic Australian plant with an extremely high antioxidant capacity. The fruit has long been used by the first Australians as a nutritional food and as a medicine and recent studies have reported its potent growth inhibitory activity against a broad panel of bacteria. Despite this, T. ferdinandiana extracts are yet to be tested for the ability to inhibit the growth of Bacillus anthracis. Materials and Methods: Solvent extracts were prepared using both the fruit and leaf of Kakadu plum. The ability to inhibit the growth of B. anthracis was investigated using a disc diffusion assay. Their MIC values were determined to quantify and compare their efficacies. Toxicity was determined using the Artemia franciscana nauplii bioassay. The most potent extracts were investigated using non-targeted GC-MS head space analysis (with screening against a compound database) for the identification and characterisation of individual components in the crude plant extracts. Results: Solvent extractions of T. ferdinandiana fruit and leaf displayed good growth inhibitory activity in the disc diffusion assay against B. anthracis. Fruit ethyl acetate and methanolic leaf extracts were particularly potent growth inhibitors, with MIC values of 451 and 377 µg/mL respectively. The fruit methanolic and chloroform extracts, as well as the aqueous leaf extracts also were good inhibitors of B. anthracis growth, albeit with lower efficacy (MIC values of 1800 and 1414 µg/mL respectively). The aqueous fruit extract and leaf chloroform extracts had only low inhibitory activity. All other extracts were completely devoid of growth inhibitory activity. Furthermore, all of the extracts with growth inhibitory activity were nontoxic in the Artemia fransiscana bioassay, with LC50 values >1000 µg/mL. Non-biased GC-MS phytochemical analysis of the most active extracts (fruit ethyl acetate and methanolic leaf) putatively identified and highlighted several compounds that may contribute to the ability of these extracts to inhibit the growth of B. anthracis. Conclusions: The low toxicity of the T. ferdinandiana fruit ethyl acetate and methanolic leaf extracts, as well as their potent growth inhibitory bioactivity against B. anthracis, indicates their potential as medicinal agents in the treatment and prevention of anthrax. [ABSTRACT FROM AUTHOR]

Introduction: Yersinia enterocolitica is a facultatively anaerobic gram negative bacterium which contaminates meat products causing the acute gastrointestinal disease yersiniosis. Terminalia ferdinandiana (Kakadu plum, gubinge) is an Australian fruit with an extremely high antioxidant capacity. It was used therapeutically by the first Australians and has documented antiseptic properties against an extensive panel of bacteria. Despite this, it has not been tested for the ability to inhibit the growth of Y. enterocolitica. Methods: T. ferdinandiana fruit and leaf extracts were extracted by maceration and the extracts were investigated by disc diffusion assay for growth inhibitory activity against a clinical strain of Y. enterocolitica. The MIC values of the extracts were determined to quantify and compare their efficacies. Toxicity was determined using the Artemia franciscana nauplii bioassay. The most potent extracts were investigated using non-targeted GC-MS analysis (with screening against a compound database) for the identification and characterisation of individual components in the crude plant extracts. Results: Solvent extractions of T. ferdinandiana leaf and fruit displayed good growth inhibitory activity in the disc diffusion assay against Y. enterocolitica. The methanolic T. ferdinandiana leaf and fruit extracts, as well as the fruit ethyl acetate extract, were particularly potent growth inhibitors, with MIC values of 372, 123 and 285 μg/mL respectively. The aqueous and ethyl acetate leaf extracts also displayed good growth inhibitory activity against Y. enterocolitica, albeit with higher MIC values (588 and 1100 μg/mL respectively). All other extracts were either low efficacy, or completely devoid of growth inhibitory activity. All T. ferdinandiana leaf and fruit extracts were either nontoxic (LC50 values <1000 μg/mL) or of low toxicity in the Artemia franciscana bioassay. Non-biased GC-MS phytochemical analysis of the methanolic extracts putatively identified and highlighted several compounds that may contribute to the ability of these extracts to inhibit the growth of Y. enterocolitica. Conclusion: The lack of toxicity and the potent growth inhibitory bioactivity of the T. ferdinandiana fruit and leaf methanolic extracts against Y. enterocolitica indicates their potential as medicinal agents in the treatment and prevention of yersiniosis. [ABSTRACT FROM AUTHOR]

Introduction: Anthrax is a severe acute disease caused by Bacillus anthracis infections. If untreated, it often results in mortality. Many Terminalia spp. have documented therapeutic properties as general antiseptics, inhibiting the growth of a wide variety of bacterial species. This study examines the ability of selected Australian Terminalia spp. extracts to inhibit B. anthracis growth. Methods:Solvent extracts were prepared from Terminalia carpentariae and Terminalia grandiflora plant material and investigated by disc diffusion assay for the ability to inhibit the growth of an environmental strain of B. anthracis. Their MIC values were determined to quantify and compare their efficacies. Toxicity was determined using the Artemia franciscana nauplii bioassay. The most potent extracts were analysed by GC-MS headspace analysis. Results: T. carpentariae and T. grandiflora leaf, fruit and nut solvent extractions displayed good growth inhibitory activity against B. anthracis. Methanolic T. carpentariae leaf and T. grandiflora nut extracts were particularly potent growth inhibitors, with MIC values of 74 and 155 µg/mL respectively. The T. carpentariae leaf ethyl acetate extract was also a good inhibitor of B. anthracis growth (MIC 340 µg/mL). All other extracts were substantially less potent growth inhibitors. Interestingly, the T. carpentariae leaf extracts with growth inhibitory activity were nontoxic in the Artemia fransiscana bioassay, with LC50 values >1000 µg/mL. In contrast, the LC50 value 740 µg/mL reported for the methanolic T. grandiflora nut extract indicates low-moderate toxicity. Non-biased GC-MS phytochemical analysis of the most active extracts (methanolic T. carpentariae leaf and T. grandiflora nut) putatively identified and highlighted several compounds that may contribute to the ability of these extracts to inhibit the growth of B. anthracis. Conclusion: The growth inhibitory activity of the methanolic T. carpentariae leaf and T. grandiflora nutextracts against B. anthracis indicates their potential for the treatment and prevention of anthrax. Furthermore, the lack toxicity of the T. carpentariae leaf and the low-moderate toxicity of the T. grandiflora nut extract, indicates that their use may extend to all forms of the disease (cutaneous, inhalation or gastrointestinal). [ABSTRACT FROM AUTHOR]

Introduction: Multiple sclerosis is an autoimmune disease which can be triggered in genetic susceptible individuals by Acinetobacter spp. and Pseudomonas aeruginosa infections. Terminalia ferdinandiana (Kakadu plum) fruit has documented therapeutic properties as a general antiseptic agent. Extracts prepared from the leaves have also been shown to block several microbial triggers of autoimmune inflammatory diseases. This study examines the ability of Kakadu plum fruit extracts to inhibit some microbial triggers of multiple sclerosis. Methods: T. ferdinandiana fruit solvent extracts were investigated by disc diffusion assay against reference and clinical strains of A.baylyi and P. aeruginosa. Their MIC values were determined to quantify and compare their efficacies. Toxicity was determined using the Artemia franciscana nauplii bioassay. Active extracts were analysed by non-targeted HPLC-QTOF mass spectroscopy (with screening against 3 compound databases) and by GC-MS (with screening against 1 compound databases) for the identification and characterisation of individual components in crude plant extracts. Results: Methanolic, aqueous and ethyl acetate T. ferdinandiana leaf extracts displayed potent antibacterial activity in the disc diffusion assay against the bacterial triggers of multiple sclerosis (A.baylyi and P. aeruginosa). The methanol and ethyl acetate extracts had the most potent growth inhibitory activity, with MIC values less than 1000 µg/ml against A. baylyi and P. aeruginosa (both reference and clinical strains). In comparison, the water extract was substantially less potent. Neither the chloroform nor hexane extracts inhibited the growth of any of the bacterial strains tested. All T. ferdinandiana fruit extracts were nontoxic in the Artemia fransiscana bioassay. Non-biased phytochemical analysis of the ethyl acetate extract revealed only low levels of the tannins gallic acid and chebulic acid and no other tannins. Conclusion: The low toxicity of the T. ferdinandiana fruit extracts and their potent inhibitory bioactivity against the bacterial triggers of multiple sclerosis indicates their potential as medicinal agents in the treatment and prevention of this disease. Phytochemical studies indicate that this activity is likely to be due to phytochemicals other than tannins. [ABSTRACT FROM AUTHOR]