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Shewanella spp. are major causes of fish spoilage. Terminalia ferdinandiana (Kakadu plum) extracts were investigated for their ability to inhibit Shewanella spp. growth. Leaf and fruit extracts displayed potent growth inhibitory properties against all Shewanella spp. The methanolic leaf extract was a particularly potent inhibitor of S. putrefaciens (DD MIC 93; LD MIC 73 μg/mL), S. baltica (DD MIC 104 μg/mL; LD MIC 85 μg/mL), S. frigidimarina (DD MIC 466 μg/mL; LD MIC 391 μg/mL) and S. loihica (DD MIC 95 μg/mL; LD MIC 55 μg/mL) growth. The aqueous and ethyl acetate leaf extracts were also potent growth inhibitors, with MIC values generally substantially <1000 μg/mL. Treatment of Acanthopagrus butcheri Munro fillets with methanolic Kakadu plum extracts significantly inhibited bacterial growth for 15 days at 4 °C. All Kakadu plum extracts were nontoxic in the Artemia franciscana bioassay. LC-MS analysis identified several compounds which may contribute to the inhibition of Shewanella spp. growth., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: Nigella sativa L., Anongessius latifolia (Roxb. ex DC.) Wall. ex Euill. and Perr. and shilajit have been used traditionally to treat numerous infectious diseases, including many caused by bacterial pathogens. However, extracts of these traditionally medicines have been poorly studied and are yet to be tested for the ability to inhibit the growth of bacterial triggers of multiple sclerosis and rheumatic fever. Materials and Methods: Antimicrobial activity of selected plant extracts was assessed using disc diffusion and liquid dilution minimum inhibitory concentration (MIC) assays against some bacterial triggers of multiple sclerosis and rheumatic fever. Interactions between the extracts and conventional antibiotics were studied and classified using the sum of the fractional inhibitory concentration (SFIC). The toxicity of the individual samples and the combinations was assessed using the artemia lethality assay (ALA) assay. Results: The methanolic A. latifolia extract displayed notable antibacterial activity against the bacterial triggers of multiple sclerosis (A. baylyi and P. aeruginosa), and rheumatic fever (S. pyogenes). Furthermore, combining the methanolic A. latifolia extract with tetracycline and chloramphenicol resulted in potentiation of the inhibitory activity against P. aeruginosa and S. pyogenes. None of the individual components (nor the combinations) were toxic in the ALA assay. Conclusion: The A. latifolia methanolic displayed clinically relevant antibacterial activity against A. baylyi, P. aeruginosa and S. pyogenes when tested alone. Furthermore, that extract also potentiated the activity of tetracycline and chloramphenicol against some bacteria. The lack of toxicity of the extracts and combinations indicates that these combinations may provide leads in the development of new therapies to prevent and treat the autoimmune diseases multiple sclerosis and rheumatic fever. [ABSTRACT FROM AUTHOR]

Introduction: An increase in antibiotic resistance and a corresponding decrease in antimicrobial discovery have directed researchers towards alternative therapies, including plant-based medicines. However, synergistic combinations of plant extracts with conventional antibiotics may be a far more effective approach in overcoming resistance and potentiating the activity of antibiotics that are otherwise ineffective against resistant bacterial strains. Materials and Methods: The antibacterial activity of Taraxacum officinale (L.) Weber ex F.H. Wigg. root extracts was investigated by disc diffusion and quantified by liquid dilution and solid phase MIC assays against some bacterial triggers of autoimmune inflammatory diseases. The extracts were also combined with a range of conventional antibiotics and tested against various bacterial pathogens. The SFIC values obtained from these assays were used to determine the class of combinational effects. Toxicity was evaluated by Artemia nauplii mortality and HDF cytotoxicity assays. Results: Methanolic and ethyl acetate T. officinale root extracts showed good inhibitory activity against several microbial triggers of autoimmune inflammatory diseases, including P. mirabilis, P. vulgaris and A. baylyi. Of further interest, some combinations of the T. officinale root extracts and conventional antibiotics potentiated bacterial growth inhibition compared to the individual components alone. Six synergistic and seven additive interactions were noted. Additionally, two antagonistic interactions were evident, indicating that those combinations should be avoided. All extracts were nontoxic in the ALA and HDF assays, verifying their safety for therapeutic usage. Conclusion: Taraxacum officinale root extracts have potential as inhibitors of bacterial triggers of selected autoimmune inflammatory diseases. Furthermore, extract components may also potentiate the activity of three antibiotics that are relatively ineffective alone. Isolation and identification of these compounds may be beneficial in drug design against several bacteria, including the microbial triggers of rheumatoid arthritis and multiple sclerosis. [ABSTRACT FROM AUTHOR]

Terminalia canescens DC. Radlk. (family: Combretaceae) is native to northern Australia. Species of the genus Terminalia are widely used as traditional medicines to treat diverse ailments, including bacterial infections. However, we were unable to find any studies that had examined the antimicrobial activity of T. canescens. In this study, T. canescens was screened against a panel of bacterial pathogens, including multi-antibiotic-resistant strains. Solvents with different polarities were used to extract different complements of phytochemicals from T. canescens leaves. Methanolic and aqueous extracts exhibited substantial antimicrobial activity against various pathogens, including those that are multidrug-resistant strains. When combined with some selected clinical antibiotics, some extracts potentiated the antibacterial inhibitory activity. This study identified two synergistic, eleven additive, eleven non-interactive and eight antagonistic interactions. The toxicities of the plant extracts were examined in the Artemia franciscana nauplii assay and were found to be non-toxic, except the aqueous extract, which showed toxicity. Metabolomic liquid chromatography–mass spectrometry (LC-MS) analyses highlighted and identified several flavonoids, including vitexin, quercetin, orientin and kaempferol, as well as the tannins ellagic acid and pyrogallol, which may contribute to the antibacterial activities observed herein. The possible mechanism of action of these extracts was further explored in this study. [ABSTRACT FROM AUTHOR]

Introduction: An increase in antibiotic resistance and a corresponding decrease in antimicrobial discovery have directed researchers towards alternative therapies, including plant-based medicines. However, synergistic combinations of plant extracts with conventional antibiotics may be a far more effective approach in overcoming resistance and potentiating the activity of antibiotics that are otherwise ineffective against resistant bacterial strains. Materials and Methods: The antibacterial activity of Taraxacum officinale (L.) Weber ex F.H. Wigg root extracts was investigated by disc diffusion assays and quantified by liquid dilution and solid phase MIC assays. The extracts were also combined with a range of conventional antibiotics and tested against gastrointestinal disease-causing bacteria. The ΣFIC values obtained from these assays were used to determine the class of combinational effects. Toxicity was evaluated by Artemia nauplii mortality and HDF cytotoxicity assays. Results: Methanolic, aqueous and ethyl acetate T. officinale root extracts showed good inhibitory activity against several gastrointestinal bacterial pathogens. The methanolic were particularly good inhibitors of S. sonneii and S. newport, with MIC values in the range 400-450 μg/mL, whilst the ethyl acetate extract was the most potent inhibitor of S. newport growth (MIC=128 μg/mL). Of further interest, some combinations of the T. officinale root extracts and conventional antibiotics potentiated bacterial growth inhibition compared to the individual components. Five synergistic and two additive interactions were noted. Interestingly, only a single antagonistic interaction was evident, indicating that nearly all combinations could be used without decreasing the antibacterial activity of the components. All extracts were nontoxic in the ALA and HDF assays. Conclusion: Taraxacum officinale root extracts have potential as inhibitors of bacterial gastrointestinal pathogens. Furthermore, extract components may also potentiate the activity of some antibiotics that are relatively ineffective alone. Isolation and identification of these compounds may be beneficial in drug design against several gastrointestinal bacterial pathogens. [ABSTRACT FROM AUTHOR]

Terminalia petiolaris A. Cunn. Ex Benth. (genus: Terminalia, family: Combretaceae) is native to Australia. Terminalia spp. have traditionally been used to treat various ailments, including bacterial infections. Solvents of varying polarity were used to extract compounds from leaves of this species, and the extracts were tested against a panel of bacteria, including antibiotic-resistant strains. The methanolic and water extracts showed substantial inhibitory activity against several bacteria, including antibiotic-resistant strains in both disc diffusion and liquid dilution assays. Combining these extracts with selected conventional antibiotics enhanced the inhibition of bacterial growth for some combinations, while others showed no significant interaction. In total, two synergistic, twenty-five additive, twenty-three non-interactive and one antagonistic interaction were observed. The methanolic and ethyl acetate plant extracts were found to be non-toxic in Artemia franciscana nauplii toxicity assays. A liquid chromatography–mass spectrometry metabolomics analysis identified several flavonoid compounds, including miquelianin, trifolin and orientin, which might contribute to the observed activities. The potential modes of these active extracts are further discussed in this study. [ABSTRACT FROM AUTHOR]

Introduction: An increase in antibiotic resistance and a corresponding decrease in antimicrobial discovery have directed researchers towards alternative therapies, including plant based medicines. However, synergistic combinations of plant extracts with conventional antibiotics may be a far more effective approach in overcoming resistance and potentiating the activity of antibiotics that are otherwise ineffective against resistant bacterial strains. Materials and Methods: The antibacterial activity of Arctium lappa L. root extracts was investigated by disc diffusion and quantified by liquid dilution and solid phase MIC assays. The extracts were also combined with a range of conventional antibiotics and tested against various microbial triggers of autoimmune diseases. The ΣFIC values obtained from these assays were used to determine the class of combinational effects. Toxicity was evaluated by Artemia nauplii mortality and HDF cytotoxicity assays. Results: Methanolic and ethyl acetate A. lappa root extracts showed good inhibitory activity against several gastrointestinal bacterial pathogens. They were particularly good inhibitors of S. sonneii and B. cereus, with MIC values in the range 150-250μg/mL. The aqueous extract was also a noteworthy inhibitor of B. cereus growth. Of further interest, some combinations of the A. lappa root extracts and conventional antibiotics potentiated bacterial growth inhibition compared to the individual components. Four synergistic and five additive interactions were noted. Notably, no antagonistic interactions were evident, indicating that all combinations could be used without decreasing the antibacterial activity of the components. All extracts were non-toxic in the ALA and HDF assays. Conclusion: Arctium lappa root extracts have potential as inhibitors of bacterial gastrointestinal pathogens. Furthermore, extract components may also potentiate the activity of some antibiotics that are relatively ineffective alone. Isolation and identification of these compounds may be beneficial in drug design against several gastrointestinal bacterial pathogens. [ABSTRACT FROM AUTHOR]

Introduction: Acne vulgaris is a skin conditions that affects most adolescents and may also afflict adults. Medicinal plant extracts may provide leads for the development of new topical and/or oral therapies for acnes vulgaris, yet many traditional medicine plants are yet to be screened for growth inhibitory activity against Cutibacterium acnes (the major bacterial cause of acne). Materials and Methods: Methanolic and aqueous Scaevola spinescens R.Br. leaf extracts were investigated by disc diffusion and liquid dilution MIC assays against Cutibacterium acnes (a significant bacterial cause of acne). Toxicity was determined using Artemia franciscana nauplii bioassays. Results: Methanolic and aqueous S. spinescens leaf extracts displayed noteworthy bacterial growth inhibitory activity against C. acnes growth. The aqueous S. spinescens leaf extract had particularly good antibacterial effects against C. acnes, with an LD MIC value of 344 μg/mL. Similar, albeit slightly higher LD MIC values were noted for the aqueous methanolic S. spinescens leaf extract against C. acnes (LD MIC = 875 μg/mL). The methanolic and aqueous S. spinescens leaf extracts were nontoxic in the Artemia fransiscana bioassay, with LC50 values substantially >1000 μg/mL. Conclusion: The lack of toxicity of the methanolic and aqueous S. spinescens leaf extracts and their noteworthy growth inhibition of C. acnes indicate their potential as treatments to alleviate acne vulgaris. Further studies are warranted to isolate and identify the active components and to determine their antibacterial mechanism. [ABSTRACT FROM AUTHOR]

The emergence of MDR bacterial pathogens has directed antibiotic discovery research towards alternative therapies and traditional medicines. Boswellia sacra oleoresin (frankincense) was used to treat bacterial infections in traditional Arabian and Asian healing systems for at least 1000 years. Despite this, B. sacra extracts have not been rigorously tested for inhibitory activity against gastrointestinal pathogens or bacterial triggers of autoimmune diseases. Solvent extracts were prepared from Boswellia sacra oleoresins obtained from three regions near Salalah, Oman. MIC values were quantified against gastrointestinal pathogens and bacterial triggers of selected autoimmune diseases by disc diffusion and broth dilution methods. The antibacterial activity was also evaluated in combination with conventional antibiotics, and the class of interaction was determined by ΣFIC analysis. Isobolograms were used to determine the optimal ratios for synergistic combinations. Toxicity was evaluated by ALA and HDF cell viability bioassays. The phytochemical composition of the volatile components of all extracts was identified by nontargeted GC-MS headspace analysis. All methanolic extracts inhibited the growth of all of the bacteria tested, although the extracts prepared using Najdi oleoresin were generally more potent than the Sahli and Houjari extracts. Combinations of the methanolic B. sacra extracts and conventional antibiotics were significantly more effective in inhibiting the growth of several bacterial pathogens. In total, there were 38 synergistic and 166 additive combinations. Approximately half of the synergistic combinations contained tetracycline. All B. sacra extracts were nontoxic in the ALA and HDF cell viability assays. Nonbiased GC-MS headspace analysis of the methanolic extracts putatively identified a high diversity of monoterpenoids, with particularly high abundances of α-pinene. The antibacterial activity and lack of toxicity of the B. sacra extracts indicate their potential in the treatment and prevention of gastrointestinal and autoimmune diseases. Furthermore, the extracts potentiated the activity of several conventional antibiotics, indicating that they may contain resistance-modifying compounds. [ABSTRACT FROM AUTHOR]

Introduction: An increase in antibiotic resistance and a corresponding decrease in antimicrobial discovery have directed researchers towards alternative therapies, including plant-based medicines. However, synergistic combinations of plant extracts with conventional antibiotics are a far more effective approach in overcoming resistance and potentiating the activity of antibiotics that are otherwise ineffective against resistant bacterial strains. Methods: In this study, Petalostigma spp. (native Australian medicinal plants) extracts were combined with a range of conventional antibiotics and tested against various microbial triggers of autoimmune diseases. The fruit and leaves were extracted separately with solvents of varying polarity and investigated for the ability to inhibit bacterial growth using disc diffusion and liquid dilution MIC techniques. Results: The methanolic and water extracts showed low to moderate inhibitory activity against several microbes. However, combinations of the mid-low polarity extracts with conventional antibiotics proved significantly more effective in inhibiting the growth of Proteus mirabilis and Acinetobacter baylyi (bacterial triggers of rheumatoid arthritis and multiple sclerosis respectively). In total, 14 different combinations proved to be synergistic. Notably, two antibiotics (chloramphenicol and erythromycin) with no inhibitory activity against P. mirabilis alone were shown to have substantial activity when tested in combination with Petalostigma spp. extracts. Conclusion: Although the mechanisms of synergy are still unclear, studies indicate that compounds within Petalostigma spp. may mimic the actions of resistance modifying agents, thus potentiating the activity of several antibiotics that are relatively ineffective alone. Isolation of these agents may be highly beneficial in drug design against several bacteria including the microbial triggers of rheumatoid arthritis and multiple sclerosis. [ABSTRACT FROM AUTHOR]

Background: The aim of this project was to investigate the efficacy of Astragalus membranaceus (Astragalus) extracts, alone and in combination with conventional antibiotics, against diarrhoea- and dysentery-causing pathogens, as well as against non-pathogenic gastrointestinal bacterial strains. The study sought to validate the chemotherapeutic potential of a traditional Chinese medicinal plant and to identify combinational therapies with increased efficacy compared to either the extracts or conventional antibiotics alone. Methods: Astragalus root powder was extracted with solvents of varying polarity and screened for inhibition of bacterial growth. Susceptibility was assessed by disc diffusion techniques, whilst the minimum inhibitory concentrations (MICs) were quantified by liquid dilution assays. To screen for combinatorial effects, the Astragalus root extracts were combined with a range of conventional antibiotics and tested against each bacterial strain using liquid dilution assays. ΣFIC values were determined and used to determine the class of interaction. Results: Aqueous Astragalus root extracts did not significantly inhibit the growth of the non-pathogenic or beneficial gut microflora bacteria E. cloacae, E. coli or E. faecalis, but possessed mild inhibitory activity against pathogenic A. faecalis, A. hydrophila, B. cereus, S. newport and S. sonnei bacteria. Combinations of the Astragalus extracts and conventional antibiotics generally produced additive or indifferent interactions, indicating that they are safe to use concomitantly without compromising the efficacy of either component. Two cases of antagonistic combinations were detected against B. cereus and S. sonnei. Conclusion: Mild inhibition of 5 pathogenic bacteria occurred with aqueous Astragalus extracts, with a number of additive and antagonistic interactions arising when tested in combination with conventional antibiotics. Astragalus may be used safely in the presence of normal gut bacteria and in most combinations with conventional antibiotics. [ABSTRACT FROM AUTHOR]

Background: Roots from Glycyrrhiza glabra L. are known for their anti-inflammatory and antimicrobial properties. This study focuses on the growth inhibitory activity of G. glabra root extracts against some bacterial triggers of autoimmune inflammatory disease alone and in combination with conventional antibiotics. Methods: G. glabra root powder was extracted with solvents of varying polarity and screened for bacterial growth inhibition by disc diffusion assay. The minimum inhibitory concentration (MIC) was quantified by both liquid dilution and disc diffusion techniques. To screen for combinatorial effects, the G. glabra root extracts were combined with a range of conventional antibiotics and tested against each bacterium using liquid dilution assays. Where synergy was detected, the optimal ratios were determined using isobologram analysis. Toxicity was examined using an Artemia nauplii and HDF bioassays. Results: G. glabra root methanolic, aqueous and ethyl acetate extracts displayed antimicrobial activity against bacterial triggers of some autoimmune inflammatory diseases. The ethyl acetate extract was particularly potent, with MIC values <500 μg/mL against K. pneumoniae and A. baylyi. The aqueous extract was also a moderate inhibitor of A. baylyi. The methanolic extract had moderate inhibitory activity against all bacteria except P. aeruginosa. Of further note, the aqueous extract interacted synergistically in combination with chloramphenicol against K. pneumoniae (Σ FIC 0.49). All extracts were nontoxic in the Artemia and HDF toxicity assays, further indicating their potential for medicinal use. Conclusion: The G. glabra ethyl acetate root extract was a strong inhibitor of the growth of K. pneumoniae and A. baylyi and therefore has potential in the prevention and treatment of ankylosing spondylitis and multiple sclerosis. In addition, the aqueous root extract potentiated the inhibitory activity of chloramphenicol against a chloramphenicol resistant K. pneumoniae strain. Although the mechanisms of synergy are still unclear, compounds within the G. glabra root extracts may mimic the actions of resistance modifying agents. Isolation of these agents may be beneficial in antibiotic drug design against bacterial triggers of ankylosing spondylitis. [ABSTRACT FROM AUTHOR]

Background: Withania somnifera (L.) Dunal roots are known for their anti-inflammatory and rejuvenative properties. This study focuses on the growth inhibitory activity of W. somnifera root extracts against some bacterial triggers of autoimmune inflammatory diseases, as well as the extracts in combination with conventional antibiotics. Methods: W. somnifera root powder was extracted with solvents of varying polarity and screened for inhibition of bacterial growth. Inhibition on agar was assessed by disc diffusion techniques, whilst the minimum inhibitory concentrations (MICs) were quantified by liquid dilution assays. To screen for combinatorial effects, the W. somnifera root extracts were combined with a range of conventional antibiotics and tested against each bacterial strain using liquid dilution assays. Extract toxicities was examined using Artemia nauplii bioassays, while their phytochemical profiles were determined using standard methodologies. Results: W. somnifera root extracts were unable to inhibit the growth of P. mirabilis, K. pneumonia, A. baylyi and Pseudomonas aeruginosa. However, the methanolic and aqueous extracts were good inhibitors of Y. enterocolitica, with MICs of 696 and 358 μg/mL respectively. These extracts also inhibited S. pyogenes growth, albeit with substantially higher MIC values indicative of only mild inhibition. Only small zones of inhibition were observed on agar for these extracts against both strains. Combinations of the W. somnifera extracts and conventional antibiotics generally produced additive or indifferent interactions, indicating that they are safe to use concomitantly without compromising the efficacy of either component. A single antagonistic combination (aqueous extract and tetracycline) against Y. enterocolitica was observed. All extracts were determined to be non-toxic as assessed in Artemia nauplii bioassays. Conclusions: Methanolic and aqueous W. somnifera extracts were strong inhibitors of Y. enterocolitica growth and mild inhibitors of S. pyogenes. These extracts were also non-toxic in the Artemia nauplii bioassay, indicating their potential for the prevention and treatment of Hashimoto's disease. [ABSTRACT FROM AUTHOR]

Introduction: Terminalia ferdinandiana Exell. is an endemic Australian plant which is known for its exceptionally high antioxidant content. The fruit is a nutritional food and the leaves and kinos were used in Australian Aboriginal medicine to treat a variety of diseases. However, T. ferdinandiana kinos remain largely unexamined for their medicinal properties. Methods: Solvent extracts were prepared from T. ferdinandiana kinos and their antiproliferative activities against G. duodenalis and were determined by direct enumeration. The anti-proliferative activities against HeLa and Caco2 cancer cell lines were determined using an MTS based cell assay. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: Methanolic and aqueous T. ferdinandiana kino extracts were strong inhibitors of Caco2 and HeLa cell proliferation, with IC50 values substantially below 1000 μg/mL. In contrast, the mid to lower polarity solvent extractions (ethyl acetate, chloroform and hexane) were less potent inhibitors of cell proliferation. The aqueous and methanolic extracts were also effective inhibitors of G. duodenalis proliferation, albeit with slightly higher IC50 values than against the Caco2 and HeLa cells. All T. ferdinandiana kino extracts were nontoxic in the Artemia franciscana bioassay, with LC50xad values substantially >1000 μg/mL. Conclusion: The antiproliferative activity of the T. ferdinandiana kino extracts against G. duodenalis and the HeLa and Caco2 cancer cell lines indicates their potential in the treatment and prevention of giardiasis and some cancers. [ABSTRACT FROM AUTHOR]

Introduction: Uncaria tomentosa is used in Central and South American folk medicine to treat a variety of diseases. It is particularly well known for treating cancer and studies have confirmed its activity against some carcinoma cell lines. However, to date, U. tomentosa extracts have only been screened against a limited panel of cancer cells. Methods: Solvent extracts were prepared from U. tomentosa inner bark and their antiproliferative activities against Caco2 and HeLa cancer cells were determined by an MTS based cell proliferation assay. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: Methanolic and aqueous U. tomentosa extracts were strong inhibitors of Caco2 and HeLa cell proliferation, with IC50 values generally below 1500 μg/mL. The methanolic extract was particularly effective, with IC50 values of 881 and 763 μg/mL against Caco2 and HeLa cells respectively. In contrast, the mid to lower polarity solvent extractions (ethyl acetate, chloroform and hexane) were less potent inhibitors of cell proliferation. Indeed, exposure of the Caco2 cells to the chloroform and hexane extracts produced proliferation levels equivalent to those of the untreated control. Cell imaging studies detected morphological features consistent with apoptosis in Caco2 cells exposed to the methanolic and aqueous U. tomentosa extracts, indicating that these extracts are functioning by cytotoxic mechanisms. All U. tomentosa extracts were nontoxic in the Artemia franciscana bioassay, with LC50 values substantially >1000 μg/mL. Conclusions: The antiproliferative activity of the U. tomentosa inner bark extracts against HeLa and Caco2 cancer cell lines indicates their potential in the treatment and prevention of some cancers. [ABSTRACT FROM AUTHOR]

Background: Khaya senegalensis (Desr.) A. Juss. is a common component of the pharmacopeia's of multiple African groupings which inhabit the areas in which it grows. Amongst these groups there is a myriad of medicinal uses in the treatment of a wide variety of bacterial, fungal and protozoal infections, as well as in the treatment of cancers. This study was undertaken to test K. senegalensis bark extracts for the ability to inhibit microbial and cancer cell growth, and thus to validate traditional African medicinal usage of this plant in treating a variety of diseases. Materials and Methods: K. senegalensis bark powder was extracted by both solvent maceration and subcritical fluid extraction (SFE). The extracts were tested for the ability to inhibit bacterial and G. duodenalis growth. Inhibition of Caco-2 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 identify phytochemical components. Results: K. senegalensis bark extracts displayed strong inhibitory activity against bacterial triggers of several autoimmune inflammatory diseases. The growth inhibitory activity of the methanolic and subcritical extracts was particularly noteworthy against P. mirabilis (MIC values of 185 and 211µg/mL, respectively against the reference strains). These extracts were similarly potent growth inhibitors of K. pneumoniae and A. baylyi, and were moderate inhibitors (MIC >1000µg/mL) of P. aeruginosa and S. pyogenes growth. The methanolic and subcritical K. senegalensis extracts were also potent inhibitors of G. duodenalis (187 and 328µg/mL, respectively), as well as Caco-2 (268 and 470µg/mL, respectively) and HeLa carcinomas (155 and 174µg/mL, respectively). GC-MS analysis of the SFE extract revealed relative abundances of a variety of mono- and sesquiterpenoids. Furthermore, all K. senegalensis bark extracts were non-toxic in the Artemia franciscana toxicity assay, indicating their safety for therapeutic use. Conclusion: These studies validate traditional African therapeutic usage of K. senegalensis in the treatment of microbial infections, autoimmune inflammatory diseases and some cancers. [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: J. communis berry is a high antioxidant fruit which is used in several traditional medicinal systems to treat a variety of diseases including rheumatism, arthritis and gout. This study was undertaken to examine the inhibitory activity of J. communis berry extracts on the growth of several bacteria associated with autoimmune inflammatory disease, and to test their ability to block CaCo2 and HeLa cancer cell proliferation. Methods: J. Communis solvent extracts were prepared using solvents of varying polarity. The extracts were investigated by disc diffusion assay for the ability to inhibit the growth of a panel of pathogenic bacteria associated with autoimmune inflammatory diseases. Their MIC values were determined to quantify and compare their efficacies. Inhibitory activity against CaCo2 and HeLa human carcinoma cell lines was evaluated using an MTS colorimetric cell proliferation assay. Toxicity was determined using the Artemia franciscana nauplii bioassay. Results: The methanol, water and ethyl acetate J. communis berry extracts displayed moderate to potent growth inhibitory activity against bacterial triggers of rheumatoid arthritis, ankylosing spondylitis and multiple sclerosis. The methanol and water extracts displayed the broadest specificity, inhibiting the growth of all bacteria tested. The ethyl acetate extract also displayed antibacterial activity, inhibiting the growth of 9 of the 13 bacterial strains (69%). The ethyl acetate extract displayed the greatest potency, with MIC values substantially below 2000 µg/mL for all bacteria which it inhibited. It was most effective at inhibiting the growth of P. mirabilis, P. vulgaris and S. aureus, each with MIC's = 500 µg/mL. The methanol and water extracts also proved effective at blocking the proliferation of the colorectal cancer cell line CaCo2 and HeLa cervical cancer cell growth, with IC50 values in the 1300-2500 µg/mL range. All extracts were non-toxic in the Artemia nauplii bioassay. Conclusion: The lack of toxicity of the J. Communis berry extracts and their potent growth inhibitory bioactivity against bacteria and HeLa and CaCo2 carcinoma cells indicates their potential in the treatment and prevention of selected autoimmune inflammatory diseases and some cancers. [ABSTRACT FROM AUTHOR]

Background: Giardiasis is a debilitating disease caused by gastrointestinal parasites of the genus Giardia. Tasmannia lanceolata (Tasmanian pepper berry) has a high anti-oxidant capacity and has documented therapeutic properties for a variety of pathogenic diseases. Materials and methods: Solvent extracts of T. lanceolata berry and leaf were investigated for the ability to block G. duodenalis growth. The IC50 values of the extracts which displayed inhibitory activity 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 crude plant extracts. Results: Methanolic, aqueous and ethyl acetate T. lanceolata berry and leaf extracts displayed potent G. duodenalis growth inhibitory activity. The methanolic extracts were the most potent growth inhibitors with IC50 values of approximately 180 µg/ml and 420 µg/ml for the berry and leaf methanolic extracts respectively. The aqueous, ethyl acetate, chloroform and hexane extracts also inhibited G. duodenalis growth, albeit with lower potency. HPLC-QTOF mass spectroscopy analysis of the extracts identified 45 compounds which were present in all T. lanceolata berry extracts. Forty of these were putatively identified by screening against 3 compound databases. All T. lanceolata berry and leaf extracts were nontoxic in the Artemia fransiscana bioassay. Conclusion: The low toxicity of the T. lanceolata extracts and their potent G. duodenalis growth inhibitory bioactivity indicates their potential as medicinal agents in the treatment and prevention of this disease. [ABSTRACT FROM AUTHOR]

Shewanella putrefaciens is a marine bacterium and a major microbial cause of spoilage in low temperature stored seafood. A survey of fruits and culinary herbs was undertaken on Australian plants with high antioxidant capacities. Twenty-eight extracts from thirteen plant species were investigated for the ability to inhibit S. putrefaciens growth. Of these, eight extracts (28.6%) substantially inhibited S. putrefaciens growth. The muntries ( Kunzea pomifera), lemon aspen ( Acronychia acidula) and desert lime ( Citrus glauca) extracts were efficient anti- S. putrefaciens agents, with MIC values ≤3000 μg mL−1. Of these, the muntries methanolic extract was the most potent growth inhibitor ( MIC = 2240 μg mL−1). The aqueous desert lime extract was also an effective growth inhibitor ( MIC of 3857 μg mL−1), whilst the methanolic bush tomato ( Solanum aviculare), aqueous muntries and Davidson's plum ( Davidsonia pruriens) extracts displayed moderate S. putrefaciens growth inhibition. All extracts were nontoxic in the Artemia fransiscana bioassay, with LC50 values (>1000 μg mL−1). Nontargeted HPLC- QTOF mass spectroscopy (with screening against three compound databases) putatively identified twenty compounds that were present in both inhibitory muntries extracts. The low toxicity of these extracts and their inhibitory bioactivity against S. putrefaciens indicates their potential as natural fish and seafood preservatives. [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]

Acute diarrhoea is becoming a major public health problem in Malaysia, with more than 13.5 million cases reported annually. Foodborne bacterial pathogens are a predominant cause of diarrhoea, with infections causing prolonged illness durations and higher patient mortality rates, placing a tremendous burden on the Malaysian economy. Due to increasing incidences of diarrhoea in Malaysia caused by foodborne pathogens and the increasing levels of resistance towards antibiotics from many different classes, new drugs and/or therapies are urgently required. The evidence for plants as new sources of antibiotics has increased dramatically in recent years and there has been a substantial increase in interest in traditional and herbal medicines. Several Terminalia spp. are native to Malaysia, with previous research demonstrating that Terminalia spp. are rich in therapeutic phytochemicals and possess antibacterial properties. However, limited research has been conducted on the native Malaysian Terminalia spp. for their potential as new antibacterial therapies. The current review discusses the types of bacteria, including antibioticresistant strains, that cause food poisoning in Malaysia, and reports the phytochemical content and antibacterial properties of eight of these useful plant species. Future directions pertaining to drug discovery pathways are also suggested. [ABSTRACT FROM AUTHOR]