Search

Background: Recent declines in new antibiotic discovery and the increase in antibiotic resistance have resulted in failing against bacterial pathogens. To develop novel antibiotic therapies, medical researchers have begun to focus on traditional therapies. Combinational therapies consisting of medicinal plants and conventional antibiotics may reactivate current drugs that are otherwise ineffective against antibioticresistant bacteria. Terminalia sericea Burch. Ex DC, Terminalia prunioides Laws. and Terminalia gazensis Bak. f. are native South African plants with antimicrobial properties. However, combinations of Terminalia sericea, Terminalia prunioides and Terminalia gazensis with conventional antibiotics are yet to be evaluated for growth inhibitory activity against gastrointestinal pathogens. Methods: Terminalia spp. leaves were extracted with solvents of varying polarity. Antimicrobial screening was performed using disc diffusion and broth microdilution assays. Toxicity was measured using Artemia franciscana nauplii lethality assays. Results: All extracts (except the T. sericea extracts) showed low to moderate inhibitory activity against B. cereus and E. faecalis, A. faecalis, A. hydrophilia, S. sonnei and S. newport in both the disc diffusion and liquid dilution assay. Twenty-three extract/antibiotic combinations produced synergy, 26 were additive, 24 were non-interactive and seven were antagonistic. Most of the antagonist interactions occurred in combinations containing gentamicin. All extracts were either non-toxic or of low toxicity in the Artemia bioassay. Conclusion: Terminalia spp. extracts may mimic the actions of a resistance modifying agents, enhancing the activity of several antibiotics that are relatively ineffective alone. Further studies are required to identify the bioactive and potentiating components and their mechanisms of action. [ABSTRACT FROM AUTHOR]

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

Introduction: 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]

Introduction: Myrrh has been used traditionally for the inhibition of microbial growth and for the treatment of rheumatic diseases. Despite this, myrrh extracts are yet to be tested for the ability to inhibit the growth of the bacterial triggers of autoimmune inflammatory diseases. Methods: Solvent extracts prepared from commercially obtained myrrh resin were analysed for the ability to inhibit the growth of bacterial species associated with initiating rheumatoid arthritis (P. mirabilis), ankylosing spondylitis (K. pneumoniae) and multiple sclerosis (A. baylyi, P. aeruginosa) by disc diffusion assay, and quantified by MIC determination. Toxicity was determined by Artemia franciscana bioassay. The most potent inhibitory extract was investigated using non-targeted GC-MS head space analysis (with screening against a compound database) for the identification and characterisation of individual components in the crude plant extracts. Results: Methanolic myrrh extract inhibited the growth of all bacterial species tested. The growth inhibition of this extract was particularly notable against P. mirabilis and K. pneumoniae, with MIC values substantially < 1000 µg/mL for both reference and clinical bacterial strains. Indeed, the MIC values of the methanolic extract against P. mirabilis reference and clinical strains were 572 and 463 µg/mL respectively. The methanolic extract also inhibited the growth of A. baylyi (MIC approximately 3000 µg/mL) and P. aeruginosa (MIC approximately 1800 µg/mL). However, the MICs against these bacteria was indicative of only moderate inhibitory activity. The aqueous, ethyl acetate, chloroform and hexane extracts also inhibited the growth of all bacterial species, albeit with moderate (MIC values 1000-5000 µg/mL) to low efficacy (MIC values >5000 µg/mL) against all bacterial species. All myrrh extracts were non-toxicin the Artemia franciscana bioassay, with LC50 values substantially above 1000 µg/mL. Non-biased GC-MS headspace analysis of the methanolic extracti dentified a high diversity of monoterpenoids and sesquiterpenoid. Conclusion: The lack of toxicity and the inhibitory activity of the methanolic myrrh extract against microbial triggers of rheumatoid arthritis, ankylosing spondylitis and multiple sclerosis indicates its potential in the treatment and prevention of these diseases. [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]

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

Background: High antioxidant capacities have been linked to the treatment and prevention of several cancers. Recent reports have identified several native Australian fruits with high antioxidant capacities. Despite this, several of these species are yet to be tested for anticancer activity. Materials and Methods: Solvent extracts prepared from high antioxidant native Australian fruits were analyzed for antioxidant capacity by the di (phenyl)-(2,4,6-trinitrophenyl) iminoazanium free radical scavenging assay. Antiproliferative activities against CaCo2 and HeLa cancer cells were determined by a multicellular tumor spheroid-based cell proliferation assay. Toxicity was determined by Artemia franciscana bioassay. Results: Methanolic extracts of all plant species displayed high antioxidant contents (equivalent to approximately 7-16 mg of vitamin C per gram of fruit extracted). Most aqueous extracts also contained relatively high antioxidant capacities. In contrast, the ethyl acetate, chloroform, and hexane extracts of most species (except lemon aspen and bush tomato) had lower antioxidant contents (below 1.5 mg of vitamin C equivalents per gram of plant material extracted). The antioxidant contents correlated with the ability of the extracts to inhibit proliferation of CaCo2 and HeLa cancer cell lines. The high antioxidant methanolic extracts of all species were potent inhibitors of cell proliferation. The methanolic lemon aspen extract was particularly effective, with IC50 values of 480 and 769 μg/mL against HeLa and CaCo2 cells, respectively. In contrast, the lower antioxidant ethyl acetate and hexane extracts (except the lemon aspen ethyl acetate extract) generally did not inhibit cancer cell proliferation or inhibited to only a minor degree. Indeed, most of the ethyl acetate and hexane extracts induced potent cell proliferation. The native tamarind ethyl acetate extract displayed low-moderate toxicity in the A. franciscana bioassay (LC50 values below 1000 μg/mL). All other extracts were nontoxic. A total of 145 unique mass signals were detected in the lemon aspen methanolic and aqueous extracts by nonbiased high-performance liquid chromatography-mass spectrometry analysis. Of these, 20 compounds were identified as being of particular interest due to their reported antioxidant and/or anticancer activities. Conclusions: The lack of toxicity and antiproliferative activity of the high antioxidant plant extracts against HeLa and CaCo2 cancer cell lines indicates their potential in the treatment and prevention of some cancers. [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]

The author discusses the criteria in selecting plants for pharmacognostic studies. The author cites that plants with a documented history of usage by traditional healers is the best choice for a good start of research while own field observations of researchers are valuable in selecting a plant species for testing. The author also notes the importance of investigating species closely related to those plants that have medicinal properties and of random selection when selecting plant species.