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Background: Terminalia ferdinandiana Exell. is an endemic Australian plant with a high anti-oxidant capacity. Liquid solvent extractions of T. ferdinandiana leaves are strong inhibitors of the growth of numerous bacterial pathogens. Despite these promising therapeutic properties, methods for the rapid extraction of large quantities of T. ferdinandiana leaves are lacking. This study aimed to develop a rapid supercritical extraction method to produce extracts which retain therapeutic properties and phytochemistry characteristics. Materials and Methods: Terminalia ferdinandiana leaves were extracted by both solvent maceration extraction and Supercritical fluid extraction (SCE). The extracts were tested for the ability to inhibit bacterial growth using the disc diffusion assay. The antibacterial potency was further quantified using liquid dilution MIC assays. Toxicity was evaluated using an Artemia franciscana nauplii bioassay and GC-MS headspace analysis was used to evaluate phytochemical similarity between the extracts. Results: Terminalia ferdinandiana leaf SCE displayed strong bacterial growth inhibitory activity against bacterial triggers of autoimmune inflammatory diseases, with efficacies similar to the smaller laboratory scale methanolic liquid extractions. The growth inhibition of the ethyl acetate and methanolic solvent extracts and the SCE were particularly noteworthy against P. mirabilis (MICs = 128, 227 and 208μg/mL respectively) and A. baylyi (MICs = 452, 780 and 104 μg/mL respectively). GC-MS analysis of the berry SCE revealed similar terpenoid components and similar abundances to those in methanolic solvent leaf extraction. Furthermore, all liquid extracts and the SCE were non-toxic in the Artemia franciscana toxicity assay. Conclusion: The T. ferdinandiana SCE retained the tested therapeutic properties, was non-toxic and had similar phytochemical profiles as the smaller scale liquid solvent extractions. Thus, SCE is a viable method of rapidly extracting large masses of T. ferdinandiana leaves to produce quality extracts that retain therapeutic properties. [ABSTRACT FROM AUTHOR]

Introduction: Podocarpus latifolius (Thunb.) R.Br. ex Mirb. is a large tree that is native to southern Africa. This species has been used extensively for multiple therapeutic purposes across the southern part of the African continent. Despite this, P. latifolius leaf extracts have not been rigorously examined growth inhibitory properties against many bacteria, including the bacterial triggers of autoimmune inflammatory diseases. Materials and Methods: The antimicrobial activity of P. latifolia leaf solvent extractions was investigated by disc diffusion and growth time course assays against some bacterial triggers of rheumatoid arthritis and ankylosing spondylitis. The growth inhibitory activity was further quantified by MIC determination. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: Methanolic and aqueous P. latifolia leaf extracts were good inhibitors of P. mirabilis and K. pneumoniae. The inhibitory activity of both extracts was particularly noteworthy against the bacterial trigger of ankylosing spondylitis (K. pneumonia), with MICs of 343 and 557 µg/mL determined for the methanolic and aqueous extracts respectively. The extracts also displayed noteworthy activity against a bacterial trigger of rheumatoid arthritis (P. mirabilis), with MICs of 580 and 634 µg/mL respectively. The antibacterial activity of the methanolic and aqueous P. latifolia leaf extracts were further investigated by growth time course assays, which showed significant growth inhibition in cultures of P. mirabilis and K. pneumoniae within 1 hr of exposure. The extracts were determined to be nontoxic in the Artemia franciscana nauplii bioassay, indicating their safety for prophylactic use in preventing these autoimmune inflammatory diseases. Conclusion: The lack of toxicity of the P. latifolia leaf extracts and their growth inhibitory bioactivity against the bacterial triggers of rheumatoid arthritis and ankylosing spondylitis indicate their potential in the development of new therapies targeting the onset of these diseases. [ABSTRACT FROM AUTHOR]

Introduction: The recent development of extensively antibiotic resistant bacteria has necessitated the search for novel anti-bacterial compounds. An examination of aromatic plants and traditional medicines is an attractive option for drug discovery. Phragmites australis (Cav.) Trin. Ex Steud. Reed is native to many regions globally, including Australia. It has yet to be tested for antibacterial activity. Materials and Methods: The ability of P. australis leaf extracts to inhibit the growth of a panel of bacterial pathogens was investigated by disc diffusion assay. Toxicity was examined using the Artemia franciscana nauplii bioassay. Results: P. australis leaf methanolic and aqueous extracts were completely ineffective at inhibiting the growth of gram-positive and gram-negative panels of bacteria. The extracts were nontoxic in the Artemia nauplii bioassay following 24 hr exposure. Conclusion: P. australis leaf extracts were completely ineffective bacterial growth inhibitors. However, these extracts may have other therapeutic properties and testing against protozoa, virus and tumour cells is required. [ABSTRACT FROM AUTHOR]

The genus Eremophila (family Scrophulariaceae) consists of approximately 200 species that are widely distributed in the semi-arid and arid regions of Australia. Multiple Eremophila spp. are used as traditional medicines by the First Australians in the areas in which they grow. They are used for their antibacterial, antifungal, antiviral, antioxidant, anti-diabetic, anti-inflammatory, and cardiac properties. Many species of this genus are beneficial against several diseases and ailments. The antibacterial properties of the genus have been relatively well studied, with several important compounds identified and their mechanisms studied. In particular, Eremophila spp. are rich in terpenoids, and the antimicrobial bioactivities of many of these compounds have already been confirmed. The therapeutic properties of Eremophila spp. preparations and purified compounds have received substantially less attention, and much study is required to validate the traditional uses and to highlight species that warrant further investigation as drug leads. The aim of this study is to review and summarise the research into the medicinal properties, therapeutic mechanisms, and phytochemistry of Eremophila spp., with the aim of focussing future studies into the therapeutic potential of this important genus. [ABSTRACT FROM AUTHOR]

Introduction: The recent development of extensively antibiotic resistant bacteria has necessitated the search for novel antibacterial therapies. An examination of aromatic plants and traditional medicines is an attractive option for drug discovery. Terminalia sericea Burch. ex DC. is a southern African native species, which has been reported to have antibacterial activity, although the effects of storage on the activity is yet to be determined. Materials and Methods: The ability of T. sericea leaf extracts to inhibit the growth of a panel of bacterial triggers of autoimmune diseases was quantified by disc diffusion and liquid dilution MIC assays. The potency of extracts prepared using fresh and stored leaves was compared. Toxicity was examined using the Artemia franciscana nauplii bioassay. Results: The T. sericea leaf methanolic and aqueous extracts displayed noteworthy growth inhibitory activity towards all bacterial pathogens tested. However, a substantial decrease in activity was seen when extracts were prepared using leaves that had been stored for two years, indicating that the leaves become less useful therapeutically over time. All extracts were non-toxic in the Artemia nauplii bioassay following 24hr exposure. Conclusion: The T. sericea leaf extracts had noteworthy antibacterial activity, although the potency decreased substantially following storage of the leaf material. [ABSTRACT FROM AUTHOR]

Introduction: Kunzea ambigua (Sm.) Druce and Kunzea flavescens C.T. White and W.D. Francis are endemic Australian plants. Decoctions, infusions and essential oils produced from the leaves were used traditionally to treat a variety of bacterial diseases. Despite this, these species have not been rigorously examined for antibacterial properties against many pathogens. Methods: The antimicrobial activity of K. ambigua and K. flavescens essential oils and a K. ambigua hydrosol was investigated by disc diffusion and liquid dilution MIC assays against a panel of pathogenic bacteria. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: K. ambigua and K. flavescens essential oils displayed noteworthy growth inhibitory activity against A. baylyi, K. pneumonia, P. mirabilis and P. aeruginosa (MIC values substantially <1000μg/mL). Indeed, MIC values as low as 33μg/mL were noted against P. aeruginosa. Noteworthy growth inhibitory activity was also noted for the K. ambigua hydrosol against A. baylyi and P. aeruginosa. All extracts were determined to be non-toxic in the Artemia franciscana nauplii bioassay, indicating their safety for internal use as well as for topical uses. Conclusion: The lack of toxicity of the Kunzea spp. extracts and their growth inhibitory bioactivity against a panel of pathogenic bacteria partially validate the traditional usage of these species to treat bacterial diseases and indicate their potential in the development of antiseptic agents. [ABSTRACT FROM AUTHOR]

Introduction: The development of antibiotic resistant bacteria has resulted in treatment failure for the current antibiotic regimen against many bacteria. A corresponding decrease in the development of new antibiotic therapies has highlighted the urgent need for the discovery of new antibiotics. An examination of 'superfoods' is an attractive option due to the high antioxidant capacities and beneficial secondary compounds reported in many 'superfoods'. This study was undertaken to test kale and spirulina extracts for the ability to inhibit the growth of a panel of bacterial pathogens of human importance. Methods: Commercially sourced kale and spirulina powders were extracted and tested for antimicrobial activity using modified disc diffusion and liquid dilution MIC methods. Toxicity was evaluated using an Artemia franciscana nauplii bioassay. Results: The methanolic and aqueous extracts of kale and spirulina displayed noteworthy growth inhibitory activity against P. mirabilis. The aqueous spirulina extract was a particularly good inhibitor of P. mirabilis, with MIC values as low as 220µg/mL. In contrast, all extracts were ineffective or of low inhibitory activity against all other bacteria tested. All extracts were non-toxic in the Artemia nauplii bioassay, confirming their suitability as natural antibacterial therapies. Conclusion: These studies indicate that aqueous kale and spirulina extracts are promising inhibitors of P. mirabilis growth and may be useful in the prevention and treatment of rheumatoid arthritis, as well as other diseases caused by that bacterium. [ABSTRACT FROM AUTHOR]

Introduction: The recent development of extensively antibiotic resistant bacteria has necessitated the search for novel antibacterial compounds. An examination of aromatic plants and traditional medicines is an attractive option for drug discovery. Astrotrichia latifolia Benth. is a native Australia shrub that has yet to be tested for antibacterial activity. Methods: The ability of A. latifolia leaf extracts to inhibit the growth of a panel of bacterial pathogens was investigated by disc diffusion assay. Toxicity was examined using the Artemia franciscana nauplii bioassay. Results: A. latifolia leaf methanolic and aqueous extracts were completely ineffective at inhibiting the growth of gram-positive and gram-negative panels of bacteria. The extracts were non-toxic in the Artemia nauplii bioassay following 24 h exposure. Conclusion: A. latifolia leaf extracts were completely ineffective bacterial growth inhibitors. However, these extracts may have other therapeutic properties and testing against protozoa, virus and tumour cells is required. [ABSTRACT FROM AUTHOR]

Introduction: Trachyspermum ammi leaves and seeds have been used as dietary supplements and to treat multiple pathogenic diseases in several traditional healing systems. Despite this, their therapeutic properties have been poorly studied. Methods: Chloroform, ethyl acetate, hexane, methanol and water extracts of T. ammi were prepared and tested and the activity was compared to that of standard antibiotics for their in vitro antibacterial activity against ten human bacterial pathogens. The antibacterial activity was studied by standard disc diffusion assays and the activity was recorded as zones of inhibition. Results: All T. ammi seed extracts were ineffective at inhibiting the growth of all of the gram-positive and gram-negative bacteria pathogens screened against. Conclusion: Despite their use in traditional healing systems to treat some pathogenic diseases, T. ammi seed extracts were completely ineffective bacterial growth inhibitors. However, these extracts were screened against a limited panel of bacteria and further testing against other pathogens is required. [ABSTRACT FROM AUTHOR]

Introduction: High antioxidant levels have been linked with multiple therapeutic properties, including antibacterial activity. Therefore, high antioxidant plant preparations are good targets for antibacterial testing. D. pruriens has high antioxidant capacity although it is yet to be tested for the ability to inhibit the growth of bacterial pathogens. Methods: The ability of D. pruriens fruit and leaf extracts to inhibit the growth of a panel of bacterial and fungal pathogens was investigated by disc diffusion assay. Toxicity was examined using the Artemia franciscana nauplii bioassay. Results: All D. pruriens fruit and leaf extracts were completely ineffective at inhibiting the growth of gram-positive and gram-negative panels of bacteria, as well as fungi. The extracts were non-toxic in the Artemia bioassay following 24 h exposure. Conclusion: Despite their high antioxidant capacity, D. pruriens fruit and leaf extracts were completely ineffective bacterial and fungal growth inhibitors. However, these extracts may have other therapeutic properties and testing against protozoa, virus and tumour cells is required. [ABSTRACT FROM AUTHOR]

Introduction: Alphitonia excelsa (Fenzl) Benth. is a large tree that is native to the east coast and northern regions of Australia. Decoctions and infusions produced from the leaves were used by the first Australians to treat a variety of bacterial diseases. Despite this, A. excelsa leaf extractions have not been rigorously examined for antibacterial properties against many pathogens. Methods: The antimicrobial activity of A. excelsa leaf extractions was investigated by disc diffusion and growth time course assays against a panel of pathogenic bacteria. The growth inhibitory activity was quantified by MIC determination. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: Polar to mid-polarity A. excelsa leaf solvent extractions inhibited the growth of a wide range of bacterial species. Growth of both gram positive and gram negative bacteria was inhibited by the A. excelsa leaf extracts to approximately the same extent. The methanolic extracts were the most potent growth inhibitor against all bacteria tested. The methanolic, aqueous and ethyl acetate A. excelsa leaf extracts were particularly potent inhibitors of P. mirabilis growth, with MIC values as low as 118µg/mL for the methanolic extract. A. hydrophilia, E. coli, K. pneumonia, S. marcenscens and B. cereus were also particularly susceptible to the methanolic extract, with MIC values generally substantially <1000 µg/mL. The antibacterial activity of the methanolic A. excelsa leaf extract was further investigated by growth time course assays which showed significant growth inhibition in cultures of P. mirabilis and B. cereus within 1 h of exposure. All extracts were determined to be nontoxic in the Artemia franciscana nauplii bioassay, indicating their safety for internal use as well as for topical uses. Conclusion: The lack of toxicity of the A. excelsa leaf extracts and their growth inhibitory bioactivity against a panel of pathogenic bacteria partially validate the traditional usage of this species to treat bacterial diseases and indicate their potential in the development of antiseptic agents. [ABSTRACT FROM AUTHOR]

Introduction: The development of multi-antibiotic resistant strains of bacteria has necessitated the search for new, effective antibacterial therapies. B. collina and B. oblongifolia leaves were used by Australian Aborigines to treat bacterial infections. However, little research has been published on antibacterial activity of these species. Methods: The ability of B. collina and B. oblongifolia leaf extracts to inhibit the growth of gram-negative and gram-positive bacterial species was investigated by disc diffusion and growth time course assays. The growth inhibitory activity was further quantified by MIC determination. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: The B. collina and B. oblongifolia leaf extracts were good inhibitors of the growth of both gram-positive and gram-negative bacteria. The B. collina and B. oblongifolia leaf extracts were particularly good inhibitors of A. faecalis growth (MICs of 225 and 486µg/mL respectively) and B. cereus growth (MICs of 515 and 875µg/mL respectively). The B. collina extract was also a good inhibitor of B. subtilis growth, whilst the B. oblongifolia extract was a moderate growth inhibitor (MIC values of 923 and 1250µg/mL respectively). A similar, trend was noted for Y. entercolitica growth inhition (MICs of 518 and 1136µg/mL respectively). Whilst MIC values were also determined against other bacterial species, they generally indicated low-moderate activity. The B. collina and B. oblongifolia leaf extracts were further investigated by growth time course assays against A. faecalis and B. cereus. Interestingly, both extracts showed significant growth inhibition within 1h of exposure against both bacterial species. All extracts were determined to be nontoxic in the Artemia franciscana nauplii bioassay, indicating their safety for the treatment of bacterial infections. Conclusion: The lack of toxicity of the B. collina and B. oblongifolia leaf extracts and their growth inhibitory bioactivity against multiple bacterial species indicate their potential in the development of new antibiotic chemotherapies. [ABSTRACT FROM AUTHOR]

Introduction: Brachychiton acerifolius (A.Cunn. ex G.Don) Macarthur and C. moore is a large tree that is native to subtropical regions of the east of Australia. Decoctions and infusions produced from the leaves of the related species Brachychiton diversifolius were used by the first Australians to treat a variety of bacterial diseases. Despite this, B. acerifolius leaf and flower extracts have not been rigorously examined for antibacterial properties against many pathogens. Methods: The antimicrobial activity of B. acerifolius leaf and flower extracts was investigated by disc diffusion and growth time course assays against a panel of pathogenic bacteria. The growth inhibitory activity was quantified by MIC determination. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: Methanolic B. acerifolius leaf and flower extracts inhibited the growth of a wide range of bacterial species. Growth of both gram positive and gramnegative bacteria was inhibited by the B. acerifolius leaf and flower extracts, although the gram negative bacteria were substantially more susceptible to the extracts than the gram positive bacteria were. The leaf extracts were more potent growth inhibitors than the flower extracts against all bacteria tested. The B. acerifolius leaf extract was a strong inhibitor of A. faecalis, K. pneumonia, P. fluorescens, S. newport, S. sonnei, B. cereus, S. aureus and S. pyogenes growth, with MIC values substantially <1000µg/mL. The antibacterial activity of the methanolic B. acerifolius leaf extract was further investigated by growth time course assays which showed significant growth inhibition in cultures of P. fluorsecens and B. cereus within 1hr of exposure. Both extracts were determined to be nontoxic in the Artemia franciscana nauplii bioassay, indicating their safety for internal use as well as for topical uses. Conclusion: The lack of toxicity of the B. acerifolius leaf and flower extracts and their growth inhibitory bioactivity against a panel of pathogenic bacteria partially validate the traditional usage of this species to treat bacterial diseases and indicates their potential in the development of antiseptic agents. [ABSTRACT FROM AUTHOR]

Introduction: Closely related plant species often share similar secondary metabolites and bioactivities and are therefore good targets for bioactivity testing when one or more species within a genus are known to possess therapeutic properties. The genus Ficus has a long history of medicinal usage in many areas of the world. Many species are known to have therapeutic properties, several species of which have well established antibacterial bioactivities. Methods: The ability of F. racemosa leaf extracts to inhibit the growth of a panel of bacterial pathogens was investigated by disc diffusion assay. Toxicity was examined using the Artemia franciscana nauplii bioassay. Results: F. racemosa methanolic and aqueous extracts were completely ineffective at inhibiting the growth of gram-positive and gram-negative panels of bacteria. The extracts were nontoxic or of low toxicity following 24 h exposure. Conclusion: Despite the close taxonomic relationship with several bioactive Ficus spp. and its therapeutic uses in traditional medicine, F. racemosa leaf extracts were completely ineffective bacterial growth inhibitors. However, these extracts may have other therapeutic properties and testing against protozoa, fungi, virus and tumour cells is required. [ABSTRACT FROM AUTHOR]

Introduction: Closely related plant species often share similar secondary metabolites and bioactivities and are therefore good targets for bioactivity testing when one or more species within a genus are known to possess therapeutic properties. The genus Eucalyptus has a long history of medicinal usage by the first Australians. Many species are known to have therapeutic properties, several species of which have well established antibacterial bioactivities. Methods: The ability of Eucalyptus grandis leaf and flower extracts to inhibit the growth of a panel of bacterial and fungal pathogens was investigated by disc diffusion assay. Toxicity was examined using the Artemia franciscana nauplii bioassay. Results: E. grandis leaf and flower methanolic and aqueous extracts were completely ineffective at inhibiting the growth of gram-positive and gram-negative panels of bacteria, as well as fungi. The extracts were nontoxic in the Artemia nauplii bioassay following 24 hr exposure. Conclusion: Despite the taxonomic relationship to several bioactive Eucalyptus spp., E. grandis leaf and flower extracts were completely ineffective bacterial and fungal growth inhibitors. However, these extracts may have other therapeutic properties and testing against protozoa, virus and tumour cells is required. [ABSTRACT FROM AUTHOR]

Introduction: The development of bacterial strains that are resistant to multiple antibiotics has made the development of new antibiotics a priority for medical research. Traditional plant medicines are important leads for the discovery of new medicines. The family Agavaceae is widely used therapeutically in many areas of the world. Despite this, many members of this family are yet to be examined extensively for therapeutic properties. The species Cordyline rubra Otto and A. Dietr. was screened for antibacterial activity in this study. Methods: The ability of C. rubra leaf and fruit extracts to inhibit the growth of a panel of bacterial pathogens was investigated by disc diffusion assay. Toxicity was examined using the Artemia franciscana nauplii bioassay. Results: Methanolic C. rubra leaf and fruit extracts were completely ineffective at inhibiting the growth of gram-positive and gramnegative panels of bacteria. The extracts were also non-toxic or of low toxicity following 24 h exposure. Conclusion: C. rubra leaf and fruit extracts were completely ineffective bacterial growth inhibitors. However, these extracts may have other therapeutic properties and testing against protozoa, fungi, virus and tumour cells is required. [ABSTRACT FROM AUTHOR]

Introduction: Closely related plant species often share similar secondary metabolites and bioactivities and are therefore good targets for bioactivity testing when one or more species within a family are known to possess therapeutic properties. The family Laminaceae has a long history of medicinal usage globally. Many species are known to have therapeutic properties, several species of which have well established antibacterial bioactivities. Methods: The ability of Westringa fruticosa leaf and flower extracts to inhibit the growth of a panel of bacterial and fungal pathogens was investigated by disc diffusion assay. Toxicity was examined using the Artemia franciscana nauplii bioassay. Results: W. fruticosa leaf methanolic and aqueous extracts were both completely ineffective at inhibiting the growth of gram-positive and gram-negative panels of bacteria, as well as fungi. The extracts were non-toxic or of low toxicity in the Artemia bioassay following 24 h exposure. Conclusion: Despite the taxonomic relationship to several bioactive Laminaceae spp., W. fruticosa leaf and flower extracts were completely ineffective bacterial and fungal growth inhibitors. However, these extracts may have other therapeutic properties and testing against protozoa, virus and tumour cells is required. [ABSTRACT FROM AUTHOR]

Background: Buchanania obovata is an endemic Australian plant that has been used traditionally to treat a variety of bacterial, fungal and protozoal pathogenic diseases. This study was undertaken to test B. obovata fruit extracts for the ability to inhibit microbial and cancer cell growth. Materials and Methods: B. obovata fruit powder was extracted and tested for antimicrobial activity using disc diffusion and MIC methods. Inhibitory activity against the gastrointestinal protozoal parasite Giardia duodenalis and antiproliferative activity against human colorectal (Caco2) and cervical (HeLa) cancer cell lines was evaluated using MTS-based colorimetric assays. Toxicity was evaluated using an Artemia franciscana nauplii bioassay. Results: The methanol, water and ethyl acetate B. obovata fruit extracts displayed potent antibacterial activity. The methanol and water extracts displayed the broadest specificity, inhibiting the growth of all of the Gram positive and Gram negative bacterial species tested. The ethyl acetate extract also displayed antibacterial activity, inhibiting the growth of 7 (88%) of the Gram negative and 2 (50%) of the Gram positive bacterial species. The methanol extract also displayed broad spectrum antifungal activity, inhibiting the growth of all 3 fungal species, including an ampicillin resistant strain of A. niger. The water extract also inhibited the growth of 2 (66%) of the fungal species tested. None of the extracts were particularly good inhibitors of the growth of the gastrointestinal parasite Giardia duodenalis. The methanolic and aqueous extracts were effective at blocking the proliferation of the colorectal cancer cell line Caco2 to between approximately 20 and 30% of the untreated cell growth. All extracts also inhibited HeLa cervical cancer cell growth. The methanol, water and ethyl acetate extracts displayed substantial toxicity in the Artemia nauplii assay. Conclusion: This study shows that B. obovata fruit extracts inhibit bacteria and fungi, but are relatively ineffective against G. duodenalis. The extracts were also effective inhibitors of Caco2 and HeLa cell proliferation, indicating that the extracts have potential in the treatment of microbial diseases and some cancers. [ABSTRACT FROM AUTHOR]

Introduction: Alpinia caerulea is a perennial herb which grows in coastal regions of Australia. All parts of this species are consumed as a bushfood. Furthermore, A. caerulea is taxonomically related to several plant species with well documented antimicrobial properties. Despite this, A. caerulea leaf solvent extractions have not previously been examined for antibacterial properties. Methods: The antimicrobial activity of A. caerulea leaf solvent extractions was investigated by disc diffusion and growth time course assays against a panel of pathogenic bacteria. The growth inhibitory activity was quantified by MIC determination. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: Methanolic and aqueous A. caerulea leaf extracts inhibited the growth of a range of gram positive and gram negative bacterial species. The methanolic extract was generally a more potent growth inhibitor than the aqueous extract. The methanolic and aqueous extracts were particularly potent inhibitors of S. marcenscens growth, with MIC values as low as 188 μg/mL for the methanolic extract. P. mirabilis (MICs of 785 and 976 μg/mL for the methanolic and aqueous extracts respectively) and K. pneumoniae growth (MICs of 1167 and 924 μg/mL for the methanolic and aqueous extracts respectively) were also particularly susceptible to the A. caerulea leaf extracts. The antibacterial activity of the methanolic and aqueous A. caerulea leaf extracts was further investigated by growth time course assays which showed significant growth inhibition in cultures of S. marcenscens and P. mirabilis within 1 h of exposure. All extracts were determined to be nontoxic in the Artemia franciscana nauplii bioassay, indicating their safety for internal use as well as for topical uses. Conclusion: The lack of toxicity of the A. caerulea leaf extracts and their growth inhibitory bioactivity against a panel of pathogenic bacteria indicate their potential in the development of antibiotic agents. [ABSTRACT FROM AUTHOR]

Introduction: Kunzea flavescens C.T.White & W.D.Francis is a shrub that is native to eastern Australia. Several Kunzea spp. have been used as traditional medicines against bacterial pathogens. Despite this, K. flavescens leaf extractions have not been rigorously examined for growth inhibitory properties against many bacterial pathogens. Methods: The antimicrobial activity of K. flavescens leaf solvent extractions was investigated by disc diffusion and growth time course assays against a panel of pathogenic bacteria. The growth inhibitory activity was quantified by MIC determination. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: Methanolic, aqueous and ethyl acetate K. flavescens leaf extracts inhibited the growth of a wide range of bacterial species. Growth of both gram positive and gram negative bacteria was inhibited by the K. flavescens leaf extracts, although a higher proportion of gram positive species were susceptible. The methanolic extract was generally more potent than the aqueous or ethyl acetate extracts against all susceptible bacteria. The methanolic K. flavescens leaf extract was a particularly potent inhibitor of P. mirabilis and K. pneumoniae growth, with MIC values of 393 and 481 μg/mL respectively. The antibacterial activity of the methanolic K. flavescens leaf extract was further investigated by growth time course assays which showed significant growth inhibition in cultures of K. pneumoniae and P. mirabilis within 1 h of exposure. All extracts were determined to be nontoxic in the Artemia franciscana nauplii bioassay, indicating their safety for internal use as well as for topical uses. Conclusions: The lack of toxicity of the K. flavescens leaf extracts and their growth inhibitory bioactivity against a panel of pathogenic bacteria indicate their potential in the development of novel antiseptic agents. [ABSTRACT FROM AUTHOR]

Introduction: Yersinia enterocolitica is a major cause of food poisoning through contaminated meat products, causing the acute gastrointestinal disease yersiniosis. Many Terminalia spp. have documented therapeutic properties as general antiseptics, inhibiting the growth of a wide variety of bacterial species. Despite this, Indian Terminalia spp. extracts have not been tested for the ability to inhibit the growth of Y. enterocolitica. Methods: T. arjuna, T. catappa and T. chebula 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. Results: T. chebula fruit extracts displayed potent growth inhibitory activity in the disc diffusion assay against Y. enterocolitica. The methanolic and ethyl acetate T. chebula fruit extracts were particularly potent growth inhibitors, with MIC values of 85 and 64 μg/mL respectively. The aqueous fruit extract also displayed good growth inhibitory activity against Y. enterocolitica, albeit with a higher MIC value (653 μg/mL). The T. arjuna branch extract was moderately active (3000 μg/mL). All other extracts were either low efficacy, or completely devoid of growth inhibitory activity. All Indian Terminalia spp. extracts were nontoxic (LC50 values <1000 μg/mL) in the Artemia franciscana bioassay. Conclusions: The lack of toxicity and the potent growth inhibitory bioactivity of the T. chebula extracts against Y. enterocolitica indicates their potential as medicinal agents in the treatment and prevention of yersiniosis. [ABSTRACT FROM AUTHOR]

Introduction: Swainsona formosa is a legumous plant which is endemic to the arid inland regions of Australia. Several Swainsona spp. were valued by the first Australian for their antiseptic properties and were used traditionally to treat a variety of bacterial diseases. Despite this, S. formosa solvent extractions have not been rigorously examined for antibacterial properties against many bacterial pathogens. Methods: The antimicrobial activity of S. formosa leaf extracts was investigated by disc diffusion and growth time course assays against a panel of pathogenic bacteria. The growth inhibitory activity was quantified by MIC determination. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: S. formosa leaf extracts inhibited the growth of a wide range of gram positive and gram negative bacteria. The methanolic extracts were generally more potent than the aqueous extracts. The methanolic and aqueous S. formosa leaf extracts were particularly potent inhibitors of A. faecalis, A. hydrophilia, K. pneumoniae, P. mirabilis, B. cereus, S. aureus and S. pyogenes growth, with MIC values substantially <1000 μg/mL and as low as 150 μg/mL against some bacteria (methanolic extract against P. mirabilis). The antibacterial activity of the methanolic and aqueous S. formosa leaf extracts was further investigated by growth time course assays which showed significant growth inhibition in cultures of all bacterial species within 1 h of exposure. All extracts were determined to be nontoxic in the Artemia franciscana nauplii bioassay, indicating their safety for therapeutic uses. Conclusions: The lack of toxicity of the S. formosa leaf extracts and their growth inhibitory bioactivity against a panel of pathogenic bacteria indicate their potential in the development of antiseptic agents. [ABSTRACT FROM AUTHOR]

Introduction: Aleurites moluccanus (L.) Willd. is a large tree with a wide global distribution. All parts of the tree have been used medicinally and the nut is consumed in a variety of cuisines. Despite this, A. moluccanus nut extracts have not been rigorously examined growth inhibitory properties against many bacteria, including the bacterial triggers of autoimmune inflammatory diseases. Methods: The antimicrobial activity of A. moluccanus nut solvent extractions was investigated by disc diffusion and growth time course assays against a panel of bacterial triggers of autoimmune diseases. The growth inhibitory activity was further quantified by MIC determination. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: Methanolic and aqueous A. moluccanus nut solvent extracts were potent inhibitors of all of the bacterial triggers of autoimmune diseases screened in this study. The methanolic extract displayed the most potent bacterial growth inhibitory activity. It was particularly potent against the bacterial triggers of rheumatoid arthritis (MICs of 438 and 215 ìg/mL against reference and clinical Proteus mirabilis strains; MIC of 187 ìg/mL against Proteus vulgaris). The methanolic extract was also a good inhibitor of K. pneumoniae and S. pyogenes growth with MICs < 1000 ìg/mL. The aqueous and ethyl acetate extracts were also potent bacterial growth inhibitors, albeit with slightly higher MIC values. The antibacterial activity of the methanolic and aqueous A. moluccanus nut extracts were further investigated by growth time course assays which showed significant growth inhibition in cultures of P. mirabilis, K. pneumpniae and S. pyogenes within 1 h of exposure. All extracts were determined to be nontoxic in the Artemia franciscana nauplii bioassay, indicating their safety for prophylactic use in preventing these autoimmune inflammatory diseases. Conclusions: The lack of toxicity of the A. moluccanus nut extracts and their growth inhibitory bioactivity against the bacterial triggers of rheumatoid arthritis, ankylosing spondylitis and rheumatic heart disease indicate their potential in the development of new therapies targeting the onset of these diseases. [ABSTRACT FROM AUTHOR]

Introduction: Cinnamomum oliveri F. M. Bailey is a rain forest tree native to Australia. Decoctions, infusions and essential oils produced from the leaves were used traditionally to treat a variety of bacterial diseases. Despite this, C. oliveri leaf extractions have not been rigorously examined for antibacterial properties against many pathogens. Methods: The antimicrobial activity of C. oliveri leaf extractions was investigated by disc diffusion and growth time course assays against a panel of pathogenic bacteria. The growth inhibitory activity was quantified by MIC determination. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: C. oliveri leaf solvent extractions inhibited the growth of a wide range of bacterial species. Growth of both gram positive and gram negative bacteria was inhibited by the C. oliveri leaf extracts to approximately the same extent. The methanolic extracts were generally most potent growth inhibitors. The methanolic, aqueous and ethyl acetate C. oliveri leaf extracts were particularly potent inhibitors of P. mirabilis growth, with MIC values as low as 127 µg/mL (methanolic extract). A. coli, K. pneumoniae and B. cereus were also particularly susceptible to the methanolic, aqueous and ethyl acetate extracts, with MIC values generally substantially <1000 μg/mL. The antibacterial activity of the methanolic C. oliveri leaf extract was further investigated by growth time course assays which showed significant growth inhibition in cultures of E. coli, K. pneumoniae and P. mirabilis within 1 h of exposure. All extracts were determined to be nontoxic in the Artemia franciscana nauplii bioassay, indicating their safety for internal use as well as for topical uses. Conclusions: The lack of toxicity of the C. oliveri leaf extracts and their growth inhibitory bioactivity against a panel of pathogenic bacteria partially validate the traditional usage of these species to treat bacterial diseases and indicate their potential in the development of antiseptic agents. [ABSTRACT FROM AUTHOR]

Introduction: A. auriculiformis, A. disparrima and A. leptoloba are native Australian Acacia spp. which were used as both foods and medicines by the first Australians. Infusions and decoctions produced from leaves and bark have reputed antiseptic properties and were used traditionally to treat a variety of bacterial diseases. Despite this, Australian Acacia spp. solvent extractions have not been rigorously examined for antibacterial properties against food spoilage and food poisoning bacteria. Methods: The antimicrobial activity of A. auriculiformis, A. disparrima and A. leptoloba leaf extracts extractions was investigated by disc diffusion and growth time course assays against a panel of food spoilage and food poisoning bacteria. The growth inhibitory activity was quantified by MIC determination. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: A. auriculiformis, A. disparrima and A. leptoloba leaf extracts inhibited the growth of a wide range of bacterial species which cause food spoilage and food poisoning. A. auriculiformis extracts were generally more potent growth inhibitors than extracts prepared from the other species, although A. disparrima extracts were also potent inhibitors of bacterial growth. With few exceptions, the methanolic extracts were more potent growth inhibitors than the other solvent extractions. The methanolic A. auriculiformis leaf extract was a particularly potent inhibitor of K. pneumoniae and P. mirabilis, B. cereus and S. aureus growth, with MIC values of 97, 132, 178 and 109 µg/mL respectively. This extract was also a good inhibitor of A. faecalis, A. hydrophilia and S. newport growth (MIC's <1000 µg/mL range). The A. disparrima extracts had a similar, albeit slightly less potent activity profiles. In contrast, the A. leptoloba leaf extracts were substantially less potent. All extracts were determined to be nontoxic in the Artemia franciscana nauplii bioassay, indicating their safety for use as natural food preservatives. Conclusions: The lack of toxicity of the A. auriculiformis, A. disparrima and A. leptoloba leaf extracts and their growth inhibitory bioactivity against a panel of food spoilage and food poisoning bacteria indicate their potential in the development of natural food preservatives. [ABSTRACT FROM AUTHOR]

Introduction: Eupomatia laurina are trees native to Australia and Papua New Guinea. The fruit of this species are consumed as a bushfood. Infusions and decoctions produced from leaves and bark have reputed antiseptic properties and were used traditionally to treat a variety of bacterial diseases. Despite this, E. laurina fruit solvent extractions have not been rigorously examined for antibacterial properties against many pathogens. Methods: The antimicrobial activity of E. laurina fruit solvent extractions was investigated by disc diffusion and growth time course assays against a panel of pathogenic bacteria. The growth inhibitory activity was quantified by MIC determination. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: Methanolic and aqueous E. laurina fruit extracts inhibited the growth of a wide range of bacterial species. Growth of both gram positive and gram negative bacteria was inhibited by the E. laurina fruit extracts to approximately the same extent. With some noteable exceptions, the methanolic extracts were generally more potent than the aqueous extracts. The methanolic and aqueous E. laurina fruit extracts were particularly potent inhibitors of P. mirabilis growth, with MIC values as low as 83 µg/mL (aqueous extract against the P. mirabilis clinical isolate). The antibacterial activity of the methanolic E. laurina fruit extract was further investigated by growth time course assays which showed significant growth inhibition in cultures of K. pneumoniae and P. mirabilis within 1 h of exposure. All extracts were determined to be nontoxic in the Artemia franciscana nauplii bioassay, indicating their safety for internal use as well as for topical uses. Conclusions: The lack of toxicity of the E. laurina fruit extracts and their growth inhibitory bioactivity against a panel of pathogenic bacteria partially validate the traditional usage of these species to treat bacterial diseases and indicate their potential in the development of antiseptic agents. [ABSTRACT FROM AUTHOR]

Introduction: B. myrtifolia and S. anisatum are native Australian trees with uses as traditional medicines and bushfoods. Essential oils produced from leaves of these species have reputed antiseptic properties. Despite this, B. myrtifolia and S. anisatum leaf solvent extractions have not been rigorously examined for antibacterial properties against many pathogens. Methods: The antimicrobial activity of aqueous and methanolic leaf extracts of B. myrtifolia and S. anisatum was investigated by disc diffusion and growth time course assays against a panel of pathogenic bacteria. The growth inhibitory activity was quantified by MIC determination. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: Methanolic and aqueous B. myrtifolia and S. anisatum leaf extracts inhibited the growth of a wide range of bacterial species. Growth of both gram positive and gram negative bacteria was inhibited the B. myrtifolia and S. anisatum extracts to approximately the same extent. In general, S. anisatum extracts were more potent inhibitors of bacterial growth than were the B. myrtifolia extracts, and (with some noteable exceptions) the methanolic extracts were generally more potent than the aqueous extracts. The B. myrtifolia and S. anisatum extracts were particularly potent inhibitors of P. mirabilis growth, with MIC values as low as 105 µg/mL (aqueous S. anisatum extract). The antibacterial activity of the methanolic B. myrtifolia and S. anisatum extracts were further investigated by growth time course assays which showed significant growth inhibition in cultures of E. coli, K. pneumpniae and P. mirabilis within 1 h of exposure. All extracts were determined to be nontoxic in the Artemia franciscana nauplii bioassay, indicating their safety for internal use as well as for topical uses. Conclusions: The lack of toxicity of the B. myrtifolia and S. anisatum extracts and their growth inhibitory bioactivity against a panel of pathogenic bacteria partially validate Australian Aboriginal usage of these species as antiseptic agent and indicate their potential in the development of antiseptic agents. [ABSTRACT FROM AUTHOR]

Background: Tasmannia lanceolata is an endemic Australian plant with a high anti-oxidant capacity. Liquid solvent extractions of T. lanceolata inhibit bacterial growth and block proliferation of several carcinomas and the gastrointestinal parasite Giardia duodenalis. Despite these promising therapeutic properties, methods for the rapid extraction of large quantities of T. lanceolata are lacking. This study aimed to develop a rapid supercritical extraction method to produce extracts which retain therapeutic propertyes and phytochemistry characteristics. Materials and Methods: T. lanceolata fruit and leaf were extracted by both solvent maceration extraction and supercritical fluid extraction (SFE). The extracts were tested for the ability to inhibit bacterial and G. duodenalis growth. Inhibition of CaCo2 and HeLa cancer cells was evaluated using MTS-based colorimetric cell proliferation assays. Toxicity was evaluated using an Artemia franciscana nauplii bioassay and GC-MS headspace analysis was used to evaluate phytochemical similarity between the extracts. Results: T. lanceolata berry and leaf SFEs displayed strong bacterial growth inhibitory activity against bacterial triggers of autoimmune inflammatory diseases, with efficacies similar to the smaller scale liquid solvent extractions. The growth inhibition of the berry SFE was particularly noteworthy against P. mirabilis and K. pneumoniae, with MIC values of approximately 160 and 190 μg/mL, respectively. The berry and leaf SFE extracts also had similar antiproliferative potencies against G. duodenalis (492 and 375 μg/mL, respectively), CaCo2 (4133 and 3347 μg/mL, respectively) and HeLa carcinomas (2652 and 3497 μg/mL, respectively) to those determined for the corresponding liquid solvent extractions. GC-MS analysis of the berry SFE revealed similar terpenoid components and similar abundances to those in liquid solvent berry extraction. Furthermore, all SFEs were either non-toxic or of only low toxicity in the Artemia franciscana toxicity assay. Conclusion: The T. lanceolata SFE retained the tested therapeutic properties, were non-toxic and had similar phytochemical profiles as smaller scale liquid solvent extractions. Thus, SFE is a viable method of rapidly extracting large masses of T. lanceolata plant material to produce quality extracts which retain therapeutic properties. [ABSTRACT FROM AUTHOR]

Introduction: Leptospermum longifolium (C.T. White & W.D. Francis) S.T. Blake, Leptospermum petersonii Bailey and Melaleuca alternifolia (Maiden & Betche) Cheel are aromatic native Australian trees with uses as traditional medicines. Essential oils produced from leaves of these species have reputed antiseptic properties against many bacteria. Despite this, L. longifolium, L. petersonii and M. alternifolia leaf solvent extractions have not been rigorously examined for antibacterial properties against many pathogens. Methods: The antimicrobial activity of methanolic L. longifolium, L. petersonii and M. alternifolia leaf extracts was investigated by disc diffusion and growth time course assays against a panel of pathogenic bacteria. The growth inhibitory activity was quantified by MIC determination. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: The methanolic L. longifolium, L. petersonii and M. alternifolia leaf extracts inhibited the growth of a wide range of bacterial species. Growth of both gram positive and gram negative bacteria was inhibited by all extracts. The L. longifolium and L. petersonii extracts were generally more potent inhibitors of bacterial growth than was the M. alternifolia extract against most bacterial species. A. hydrophilia, C. freundi, P. mirabilis and B. cereus growth was particularly susceptible to the extracts, with MIC values as low as 147 µg/mL (inhibition of A. hydrophilia growth by the L. longifolium extract). The antibacterial activity of the L. longifolium, L. petersonii and M. alternifolia extracts were further investigated by growth time course assays, with significant growth inhibition recorded in all cultures within 1 h of exposure. All extracts were determined to be nontoxic in the Artemia franciscana nauplii bioassay, indicating their safety for therapeutic uses. Conclusions: The lack of toxicity of the methanolic L. longifolium, L. petersonii and M. alternifolia leaf extracts and their growth inhibitory bioactivity against a panel of pathogenic bacteria partially validate Australian Aboriginal usage of these species as antiseptic agents and indicate their potential in the development of antiseptic agents. [ABSTRACT FROM AUTHOR]

Background: Foods with high oil and fatty acid contents have been linked with a variety of medicinal properties including bacterial growth inhibition, anti-Giardial activity and the inhibition of cancer cell proliferation. Almond, cashew, hazelnut and walnut contain very high fatty acid contents. Despite this, these nuts have not been adequately screened for medicinal properties. Materials and Methods: Almond, cashew, hazelnut and walnut powders were extracted and tested for antimicrobial activity using modified disc diffusion and MIC methods. Inhibitory activity against the gastrointestinal protozoal parasite Giardia duodenalis and against CaCo2 cancer cells were evaluated using colorimetric cell proliferation assays. Toxicity was evaluated using an Artemia franciscana nauplii bioassay. Results: The methanolic almond and walnut solvent extractions displayed broad spectrum growth inhibitory activity, inhibiting the growth of 100% and 7 of the 11 (64%) bacterial strains tested respectively. The methanolic walnut extract was a particularly potent growth inhibitor, with MIC values of ~1000 μg/mL, 700 μg/mL and 800 μg/mL against A. baylyi, P. mirabilis and P. vulgaris respectively. The methanolic almond extract also had moderate to inhibitory activity against E. coli (MIC ~2000 μg/mL), P. mirabilis and P. vulgaris (both ~2500 μg/mL). The methanolic cashew and hazelnut extracts were moderate inhibitors of E. coli growth (~2500 and 1250 μg/mL respectively). The methanolic almond extract was also a potent inhibitor of G. duodenalis proliferation (IC50 878 μg/mL). All extracts were ineffective at blocking the growth of the colorectal cancer cell line CaCo2. Instead, most of the extracts substantially stimulated proliferation. All of the nut extracts were non-toxic in the Artemia nauplii bioassay. Conclusion: The bacterial growth inhibitory activities of the methanolic almond and walnut extracts, the anti-Giardial activity of the methanolic almond extract and their lack of toxicity indicates the potential of these extracts in the discovery and development of new natural antibiotic agents. [ABSTRACT FROM AUTHOR]

Introduction: Streptococcus pyogenes can cause a variety of diseases including streptococcal pharyngitis, impetigo and rheumatic heart disease, dependant on which tissue it infects. Many Australian plants have documented therapeutic properties as general antiseptics, but are yet to be tested for the ability to inhibit S. pyogenes growth. Methods: Solvent extracts were prepared using Australian plants with documented ethnobotanical usage to treat bacterial infections, or published antibacterial activity. The extracts were investigated by disc diffusion assay for the ability to inhibit the growth of a clinical strain of S. pyogenes. Their MIC values were determined to quantify and compare their efficacies. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: S. pyogenes growth was inhibited by 24 of the 34 extracts tested. The Eucalyptus spp. extracts were particularly potent. MIC values of 341 and 88 μg/ mL were determined for the aqueous and methanolic E. baileyana extracts respectively. Similarly, MIC values of 134 and 53 μg/mL were determined for the aqueous and methanolic E. major extracts respectively. The methanolic wattle seed extract, aqueous and methanolic lemon aspen extracts, aqueous native thyme extract, methanolic river mint extract and the methanolic native basil extract were similarly potent growth inhibitors, with MIC values =1000 μg/mL. Several other extracts (methanolic native tamarind, bush tomato, desert lime, native thyme, native sage and the T. stipitata leaf extracts, as well as the aqueous river mint, native basil, T. stipitata leaf extracts) displayed moderate growth inhibitory activity (MIC=1000-5000 μg/mL). All other extracts were either low potency S. pyogenes growth inhibitors or were devoid of inhibitory activity. The E. baileyana and E. major methanolic extracts, as well as the E. baileyana aqueous extract induced significant mortality in the Artemia fransiscana bioassay, with LC50 values substantially <1000 μg/mL. All other extracts were nontoxic, with LC50 values >1000 μg/mL. Conclusion: The potent growth inhibitory bioactivity of the Eucalyptus spp., lemon aspen, wattle seed, native basil and river mint extracts against S. pyogenes demonstrates their potential for the treatment and prevention of S. pyogenes induced disease. However, the toxicity of the Eucalyptus spp. extracts may limit their use to topical treatments for pharyngitis and impetigo. As the lemon aspen, wattle seed, native basil and river mint extracts were nontoxic, they may also have wider uses in treating systemic illnesses such as rheumatic fever, rheumatic heart disease and cellulitis. [ABSTRACT FROM AUTHOR]

Introduction: Streptococcus pyogenes is a gram-positive, pathogenic bacterium which causes a variety of diseases including streptococcal pharyngitis, impetigo and rheumatic heart disease, depending on which tissue it infects. Many Terminalia spp. have documented therapeutic properties as general antiseptics, inhibiting the growth of a wide variety of bacterial species. Methods: Solvent extracts were prepared using Indian Terminalia spp. with documented ethnobotanical usage to treat bacterial infections, or published antibacterial activity. The extracts were investigated by disc diffusion assay for the ability to inhibit the growth of a clinical strain of S. pyogenes. Their MIC values were determined to quantify and compare their efficacies. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: T. arjuna, T. catappa and T. chebula methanolic and ethyl acetate extracts displayed potent antibacterial activity in the disc diffusion assay against S. pyogenes. The T. catappa and T. chebula ethyl acetate extracts were particularly potent, with MIC values of 225 and 205 μg/mL respectively. All methanolic extracts were also potent growth inhibitors with MIC values of 268 μg/mL (T. arjuna methanolic extract), 425 μg/mL (T. catappa methanolic extract) and 300 μg/mL (T. chebula methanolic extract). The T. catappa hexane extract was also a potent S. pyogenes growth inhibitor (MIC 768 μg/mL). All other extracts were either ineffective or were of only low efficacy. Furthermore, all of the Indian Terminalia spp. extracts were nontoxic in the Artemia fransiscana bioassay, with LC50 values >1000 μg/mL. Conclusion: The potent growth inhibitory bioactivity of the methanolic and ethyl acetate T. arjuna, T. catappa and T. chebula extracts against S. pyogenes demonstrates their potential for the treatment and prevention of pharyngitis, impetigo and rheumatic heart disease. All extracts were nontoxic indicating their safety for therapeutic use. [ABSTRACT FROM AUTHOR]

Anthrax is a zoonotic disease caused by the soil bacterium Bacillus anthracis. It has an extremely high mortality rate if untreated. Terminalia spp. have a long association with the treatment of various ailments, including bacterial infections although they have not been tested for the ability to inhibit the growth of B. anthracis. Methods: Solvent extracts were prepared using Terminalia spp. known to inhibit microorganism growth. The antibacterial potential of the extracts were investigated by disc diffusion assay to determine the growth inhibitory potential against an environmental strain of B. anthracis. Their MIC values were calculated to quantify and compare their relative efficacies. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: Extracts prepared from several Indian Terminalia spp. displayed potent antibacterial activity in the disc diffusion assay against B. anthracis. The methanolic T. chebula fruit extract was particularly effective at inhibiting microbial growth, with MIC values against B. anthracis of 166 μg/mL (<2 μg impregnated in the disc). The aqueous T. chebula extract, as well as T. catappa and T. arjuna methanolic extracts, were also good growth inhibitors with MIC's generally <2500 μg/mL (<25 μg impregnated in the disc). All other plant extracts were either inactive or of only low inhibitory activity. None of the extracts were deemed toxic, with all recorded LC50 values substantially>1000 μg/mL. [ABSTRACT FROM AUTHOR]

Introduction: Anthrax is a zoonotic disease caused by the bacterium Bacillus anthracis. It is often fatal if left untreated. Many Australian plants 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 plant extracts to inhibit B. anthracis growth. Methods: Solvent extracts were prepared using plants with documented ethnobotanical usage to treat bacterial infections, or published antibacterial activity. The extracts were 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. Results: Methanolic and aqueous extracts of Eucalyptus baileyana and Eucalyptus major displayed potent antibacterial activity in the disc diffusion assay against B. anthracis. The methanolic extracts were particularly potent with MIC values as low as 290 μg/mL (E. major methanolic extract). Tasmannia insipidia and Tasmannia stipitata extracts also inhibited B. anthracis growth, albeit with low efficacy. The E. baileyana and E. major methanolic leaf extracts as well as the E. baileyana aqueous leaf extract induced significant mortality in the Artemia fransiscana bioassay, with LC50 values substantially <1000 μg/mL, indicating the toxicity of these extracts. Conclusion: The potent inhibitory bioactivity of the E. baileyana and E. major extracts against B. anthracis demonstrate their potential as medicinal agents in the treatment and prevention of anthrax. However, their toxicity indicates that their use may be limited to the treatment of the cutaneous form of the disease, or for sterilisation of infected sites. [ABSTRACT FROM AUTHOR]