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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: Clostridium perfringens is the etiological agent of clostridial myonecrosis and enteritis necroticans. Infections result in exotoxin production, tissue necrosis and unless promptly treated, may result in death. Terminalia ferdinandiana (Kakadu plum) fruit has documented therapeutic properties as a general antiseptic agent. Fruit extracts have been reported to inhibit the growth of an extensive panel of pathogenic bacteria. Leaf extracts have also been shown to block the growth of several bacterial species associated with autoimmune inflammatory diseases. Methods: T. ferdinandiana fruit and leaf solvent extracts were investigated for growth inhibitory activity by disc diffusion assay against a clinical strain of Clostridium perfringens. 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) for the identification and characterisation of individual components in the crude plant extracts. Results: Methanolic and aqueous T. ferdinandiana fruit and leaf extracts, as well as the leaf ethyl acetate extract, displayed growth inhibitory activity in the disc diffusion assay against C. perfringens. The leaf extracts were generally more potent growth inhibitors than the corresponding fruit extracts, although the aqueous fruit extract had substantially greater efficacy than the aqueous leaf extract. The methanolic and ethyl acetate leaf extracts were particularly potent growth inhibitors, with MIC values of 206 and 117 µg/ml respectively. The fruit methanolic extract also displayed good efficacy, with an MIC of 716 µg/ml. In contrast, the chloroform and hexane extracts of both fruit and leaf were completely devoid of growth inhibitory activity. All T. ferdinandiana extracts were either nontoxic or of low toxicity in the Artemia fransiscana bioassay. Non-biased phytochemical analysis of the methanolic and ethyl acetate leaf extracts revealed the presence of high relative levels of a diversity of galloand ellagi- tannins. Conclusion: The low toxicity of the T. ferdinandiana extracts and the potent growth inhibitory bioactivity of the leaf methanolic and ethyl acetate extracts against C. perfringens indicates their potential as medicinal agents in the treatment and prevention of clostridial myonecrosis and enteritis necroticans. Metabolomic profiling studies indicate that these extracts contained a diversity of tannins. [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]