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The wound management field faces significant challenges due to antimicrobial resistance (AMR) and the complexity of chronic wound care. Effective wound treatment requires antimicrobial dressings to prevent bacterial infections. However, the rise of AMR necessitates new antimicrobial agents for wound dressings, particularly for addressing bacterial pathogens like methicillin-resistant Staphylococcus aureus (MRSA). Endophytic fungi, known for producing diverse bioactive compounds, represent a promising source of such new agents. This study tested thirty-two endophytic fungi from thirteen distinct Australian native plants for their antibacterial activity against S. aureus. Ethyl acetate (EtOAc) extracts from fungal culture filtrates exhibited inhibitory effects against both methicillin-sensitive S. aureus ATCC 25923 (MIC = 78.1 µg/mL) and MRSA M180920 (MIC = 78.1 µg/mL). DNA sequence analysis was employed for fungal identification. The most active sample, EL 19 (Chaetomium globosum), was selected for further analysis, revealing that its EtOAc extracts reduced S. aureus ATCC 25923 biofilm formation by 55% and cell viability by 57% to 68% at 1 2 × MIC. Furthermore, cytotoxicity studies using the brine shrimp lethality test demonstrated low cytotoxicity up to 6 × MIC (25% mortality rate) with an LC50 value of 639.1 µg/mL. Finally, the most active sample was incorporated into polycaprolactone (PCL) fiber mats via electrospinning, with resultant inhibition of S. aureus species. This research underscores the potential of endophytic fungi from Australian plants as sources of substances effective against common wound pathogens. Further exploration of the responsible compounds and their mechanisms could facilitate the development of wound dressings effective against MRSA and innovative biofilm-resistant electrospun fibers, contributing to the global efforts to combat AMR. [ABSTRACT FROM AUTHOR]

Hospital-acquired diarrhoea (HAD) is common, and often associated with gut microbiota and metabolome dysbiosis following antibiotic administration. Clostridioides difficile is the most significant antibiotic-associated diarrhoeal (AAD) pathogen, but less is known about the microbiota and metabolome associated with AAD and C. difficile infection (CDI) with contrasting antibiotic treatment. We characterised faecal microbiota and metabolome for 169 HAD patients (33 with CDI and 133 non-CDI) to determine dysbiosis biomarkers and gain insights into metabolic strategies C. difficile might use for gut colonisation. The specimen microbial community was analysed using 16 S rRNA gene amplicon sequencing, coupled with untargeted metabolite profiling using gas chromatography-mass spectrometry (GC-MS), and short-chain fatty acid (SCFA) profiling using GC-MS. AAD and CDI patients were associated with a spectrum of dysbiosis reflecting non-antibiotic, short-term, and extended-antibiotic treatment. Notably, extended antibiotic treatment was associated with enterococcal proliferation (mostly vancomycin-resistant Enterococcus faecium) coupled with putative biomarkers of enterococcal tyrosine decarboxylation. We also uncovered unrecognised metabolome dynamics associated with concomitant enterococcal proliferation and CDI, including biomarkers of Stickland fermentation and amino acid competition that could distinguish CDI from non–CDI patients. Here we show, candidate metabolic biomarkers for diagnostic development with possible implications for CDI and vancomycin-resistant enterococci (VRE) treatment. Antibiotics can cause hospital-acquired diarrhoea, resulting in gut microbiota and metabolome changes. Here, the authors study the faecal microbiota and metabolome of 169 patients, offering insights into these changes, and identified biomarkers for diagnostics. [ABSTRACT FROM AUTHOR]

The continual emergence of antibiotic-resistant bacteria and the slow development of new antibiotics has driven the resurgent interest in the potential application of bacteriophages as antimicrobial agents in different medical and industrial sectors. In the present study, the potential of combining phage biocontrol and a natural plant compound (carvacrol) in controlling Escherichia coli on fresh-cut mixed vegetable was evaluated. Four coliphages, designated Escherichia phage SUT_E420, Escherichia phage SUT_E520, Escherichia phage SUT_E1520 and Escherichia phage SUT_E1620, were isolated from raw sewage. Biological characterization revealed that all four phages had a latent period of 20–30 min and a burst size ranging from 116 plaque-forming units (PFU)/colony forming units (CFU) to 441 PFU/CFU. The phages effectively inhibited the growth of respective host bacteria in vitro, especially when used at a high multiplicity of infection (MOI). Based on transmission electron microscopy analysis, all phages were classified as tailed phages in the class of Caudoviricetes. Additionally, next generation sequencing indicated that none of the selected coliphages contained genes encoding virulence or antimicrobial resistance factors, highlighting the suitability of isolated phages as biocontrol agents. When a phage cocktail (~109 PFU/mL) was applied alone onto fresh-cut mixed vegetables artificially contaminated with E. coli, no bacteria were recovered from treated samples on Day 0, followed by a gradual increase in the E. coli population after 24 h of incubation at 8 °C. On the other hand, no significant differences (p < 0.05) were observed between treated and non-treated samples in terms of E. coli viable counts when carvacrol at the minimum inhibitory concentration (MIC) of 6.25 μL/mL was applied alone. When a phage cocktail at an MOI of ~1000 and MIC carvacrol were applied in combination, no E. coli were recovered from treated samples on Day 0 and 1, followed by a slight increase in the E. coli population to approximately 1.2–1.3 log CFU/mL after 48 h of incubation at 8 °C. However, total elimination of E. coli was observed in samples treated with a phage cocktail at a higher MOI of ~2000 and carvacrol at MIC, with a reduction of approximately 4 log CFU/mL observed at the end of Day 3. The results obtained in this study highlight the potential of combined treatment involving phage biocontrol and carvacrol as a new alternative method to reduce E. coli contamination in minimally processed ready-to-eat foods. [ABSTRACT FROM AUTHOR]

The microbiome of the human gut is a complex assemblage of microorganisms that are in a symbiotic relationship with one another and profoundly influence every aspect of human health. According to converging evidence, the human gut is a nodal point for the physiological performance matrixes of the vital organs on several axes (i.e. gut-brain, gut-lung, etc). As a result of COVID-19, the importance of gut-lung dysbiosis (balance or imbalance) has been realised. In view of this, it is of utmost importance to develop a comprehensive understanding of the microbiome, as well as its dysbiosis. In this review, we provide an overview of the gut-lung axial microbiome and its importance in maintaining optimal health. Human populations have successfully adapted to geophysical conditions through traditional dietary practices from around the world. In this context, a section has been devoted to the traditional Indian system of medicine and its theories and practices regarding the maintenance of optimally customized gut health. [ABSTRACT FROM AUTHOR]

The threat to public health resulting from the emergence of antimicrobial resistance (AMR) is ever rising. One of the major bacterial pathogens at the forefront of this problem is methicillin-resistant Staphylococcus aureus, or MRSA, for which there is a great need to find alternative treatments. One of the most promising alternatives is endophytic fungi, which were shown to produce a vast array of bioactive compounds, including many novel antibacterial compounds. In this study, two endophytic Alternaria sp., EL 24 and EL 35, were identified from the leaves of Eremophila longifolia. Ethyl acetate (EtOAc) extracts of their culture filtrates were found to inhibit both methicillin-sensitive S. aureus ATCC 25923 and MRSA strains M173525 and M180920. The activity of each extract was shown to be greatly affected by the growth medium, with considerable reductions in minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) observed when tested in tryptic soy broth with glucose (TSBG) compared with Mueller–Hinton broth (MHB). Both extracts displayed significant (p ≤ 0.05) antibiofilm activity against all three S. aureus strains, the greatest of which was that of EL 35, which reduced biofilm formation by M180920 by 72%, while that of EL 24 resulted in a 57% reduction against ATCC 25923. Both extracts also disrupted established biofilms, of which the most effective was EL 35, which reduced the M180920 biofilm by 64%, while EL 24 also performed best against M180920, reducing biofilm by 54%. Gas chromatography–mass spectrometry (GC-MS) analysis of the EL 24 EtOAc extract revealed five known compounds. This study highlights the promise of endophytic fungi from Australian plants as a potential source of substances effective against important bacterial pathogens. Further understanding of the responsible compounds and their mechanisms could lead to the development of treatments effective against MRSA, as well as novel biofilm-resistant biomedical materials, contributing towards reducing the burden of AMR. [ABSTRACT FROM AUTHOR]

Endophytic fungi and bacteria live asymptomatically within plant tissues. In recent decades, research on endophytes has revealed that their significant role in promoting plants as endophytes has been shown to enhance nutrient uptake, stress tolerance, and disease resistance in the host plants, resulting in improved crop yields. Evidence shows that endophytes can provide improved tolerances to salinity, moisture, and drought conditions, highlighting the capacity to farm them in marginal land with the use of endophyte-based strategies. Furthermore, endophytes offer a sustainable alternative to traditional agricultural practices, reducing the need for synthetic fertilizers and pesticides, and in turn reducing the risks associated with chemical treatments. In this review, we summarise the current knowledge on endophytes in agriculture, highlighting their potential as a sustainable solution for improving crop productivity and general plant health. This review outlines key nutrient, environmental, and biotic stressors, providing examples of endophytes mitigating the effects of stress. We also discuss the challenges associated with the use of endophytes in agriculture and the need for further research to fully realise their potential. [ABSTRACT FROM AUTHOR]

Wound care is a global health issue with a financial burden of up to US $96.8 billion annually in the USA alone. Chronic non-healing wounds which show delayed and incomplete healing are especially problematic. Although there are more than 3000 dressing types in the wound management market, new developments in more efficient wound dressings will require innovative approaches such as embedding antibacterial additives into wound-dressing materials. The lack of novel antibacterial agents and the misuse of current antibiotics have caused an increase in antimicrobial resistance (AMR) which is estimated to cause 10 million deaths by 2050 worldwide. These ongoing challenges clearly indicate an urgent need for developing new antibacterial additives in wound dressings targeting microbial pathogens. Natural products and their derivatives have long been a significant source of pharmaceuticals against AMR. Scrutinising the data of newly approved drugs has identified plants as one of the biggest and most important sources in the development of novel antibacterial drugs. Some of the plant-based antibacterial additives, such as essential oils and plant extracts, have been previously used in wound dressings; however, there is another source of plant-derived antibacterial additives, i.e., those produced by symbiotic endophytic fungi, that show great potential in wound dressing applications. Endophytes represent a novel, natural, and sustainable source of bioactive compounds for therapeutic applications, including as efficient antibacterial additives for chronic wound dressings. This review examines and appraises recent developments in bioactive wound dressings that incorporate natural products as antibacterial agents as well as advances in endophyte research that show great potential in treating chronic wounds. [ABSTRACT FROM AUTHOR]

Apicomplexan infections, such as giardiasis and cryptosporidiosis, negatively impact a considerable proportion of human and commercial livestock populations. Despite this, the molecular mechanisms of disease, particularly the effect on the body beyond the gastrointestinal tract, are still poorly understood. To highlight host–parasite–microbiome biochemical interactions, we utilised integrated metabolomics-16S rRNA genomics and metabolomics–proteomics approaches in a C57BL/6J mouse model of giardiasis and compared these to Cryptosporidium and uropathogenic Escherichia coli (UPEC) infections. Comprehensive samples (faeces, blood, liver, and luminal contents from duodenum, jejunum, ileum, caecum and colon) were collected 10 days post infection and subjected to proteome and metabolome analysis by liquid and gas chromatography–mass spectrometry, respectively. Microbial populations in faeces and luminal washes were examined using 16S rRNA metagenomics. Proteome–metabolome analyses indicated that 12 and 16 key pathways were significantly altered in the gut and liver, respectively, during giardiasis with respect to other infections. Energy pathways including glycolysis and supporting pathways of glyoxylate and dicarboxylate metabolism, and the redox pathway of glutathione metabolism, were upregulated in small intestinal luminal contents and the liver during giardiasis. Metabolomics-16S rRNA genetics integration indicated that populations of three bacterial families—Autopobiaceae (Up), Desulfovibrionaceae (Up), and Akkermanasiaceae (Down)—were most significantly affected across the gut during giardiasis, causing upregulated glycolysis and short-chained fatty acid (SCFA) metabolism. In particular, the perturbed Akkermanasiaceae population seemed to cause oxidative stress responses along the gut–liver axis. Overall, the systems biology approach applied in this study highlighted that the effects of host–parasite–microbiome biochemical interactions extended beyond the gut ecosystem to the gut–liver axis. These findings form the first steps in a comprehensive comparison to ascertain the major molecular and biochemical contributors of host–parasite interactions and contribute towards the development of biomarker discovery and precision health solutions for apicomplexan infections. [ABSTRACT FROM AUTHOR]

Over the last few decades, many of the existing drugs used to treat infectious diseases have become increasingly ineffective due to the global emergence of antimicrobial resistance (AMR). As such, there is a constant demand to find new, effective compounds that could help to alleviate some of this pressure. Endophytic fungi have captured the attention of many researchers in this field, as they have displayed a vast ability to produce novel bioactive compounds, many of which possess wide-ranging antimicrobial activities. However, while highly promising, research in this area is still in its infancy. Endophytes inhabit the healthy tissues of plants asymptomatically, resulting in a mutualistic symbiosis in which the endophytes produce a plethora of bioactive compounds that support the fitness of the host plant. These compounds display great chemical diversity, representing structural groups, such as aliphatic compounds, alkaloids, peptides, phenolics, polyketides and terpenoids. In this review, the significant antimicrobial potential of endophytic fungi is detailed, highlighting their ability to produce novel and diverse antimicrobial compounds active against human, plant and marine pathogens. In doing so, it also highlights the significant contributions that endophytic fungi can make in our battle against AMR, thus providing the motivation to increase efforts in the search for new and effective antimicrobial drugs. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 is the cause of the COVID-19 pandemic which has claimed more than 6.5 million lives worldwide, devastating the economy and overwhelming healthcare systems globally. The development of new drug molecules and vaccines has played a critical role in managing the pandemic; however, new variants of concern still pose a significant threat as the current vaccines cannot prevent all infections. This situation calls for the collaboration of biomedical scientists and healthcare workers across the world. Repurposing approved drugs is an effective way of fast-tracking new treatments for recently emerged diseases. To this end, we have assembled and curated a database consisting of 7817 compounds from the Compounds Australia Open Drug collection. We developed a set of eight filters based on indicators of efficacy and safety that were applied sequentially to down-select drugs that showed promise for drug repurposing efforts against SARS-CoV-2. Considerable effort was made to evaluate approximately 14,000 assay data points for SARS-CoV-2 FDA/TGA-approved drugs and provide an average activity score for 3539 compounds. The filtering process identified 12 FDA-approved molecules with established safety profiles that have plausible mechanisms for treating COVID-19 disease. The methodology developed in our study provides a template for prioritising drug candidates that can be repurposed for the safe, efficacious, and cost-effective treatment of COVID-19, long COVID, or any other future disease. We present our database in an easy-to-use interactive interface (CoviRx that was also developed to enable the scientific community to access to the data of over 7000 potential drugs and to implement alternative prioritisation and down-selection strategies. [ABSTRACT FROM AUTHOR]

Treated recreational water facilities, including swimming pools and water play parks, have often been implicated in infectious disease outbreaks. Addressing this problem is complex due to the multiple and interrelated factors contributing to outbreaks in these settings. These factors may relate to inappropriate behaviours of users and operators, lack of and inconsistent regulation of these facilities, insufficient facility maintenance, and problems associated with the design of these facilities. Given the complexity of this issue, we argue that the Socio-Ecological Model (SEM) provides a useful framework to help identify the multi-level influences and factors that have implications for designing interventions to prevent this public health problem, whilst assisting in guiding future research in this area. We apply the SEM to the current literature to help identify the influences and factors contributing to infectious disease outbreaks in treated recreational water facilities to support this argument. We also identify several gaps in the existing research that would benefit from further examination to help prevent infectious disease outbreaks in treated recreational water facilities such as public swimming pools and water play parks. [ABSTRACT FROM AUTHOR]

The primary flavonoid, pinocembrin, is thought to have a variety of medical uses which relate to its reported anti-oxidant, anti-inflammatory, anti-microbial and anti-cancer properties. Some studies have reported that this flavonoid has anti-fibrotic activities. In this study, we investigated whether pinocembrin would impede fibrosis, dampen inflammation and improve lung function in a large animal model of pulmonary fibrosis. Fibrosis was induced in two localized lung segments in each of the 10 sheep participating in the study. This was achieved via two infusions of bleomycin delivered bronchoscopically at a two-week interval. Another lung segment in the same sheep was left untreated, and was used as a healthy control. The animals were kept for a little over 5 weeks after the final infusion of bleomycin. Pinocembrin, isolated from Eucalyptus leaves, was administered to one of the two bleomycin damaged lung segments at a dose of 7 mg. This dose was given once-weekly over 4-weeks, starting one week after the final bleomycin infusion. Lung compliance (as a measure of stiffness) was significantly improved after four weekly administrations of pinocembrin to bleomycin-damaged lung segments. There were significantly lower numbers of neutrophils and inflammatory cells in the bronchoalveolar lavage of bleomycin-infused lung segments that were treated with pinocembrin. Compared to bleomycin damaged lung segments without drug treatment, pinocembrin administration was associated with significantly lower numbers of immuno-positive CD8+ and CD4+ T cells in the lung parenchyma. Histopathology scoring data showed that pinocembrin treatment was associated with significant improvement in inflammation and overall pathology scores. Hydroxy proline analysis showed that the administration of pinocembrin did not reduce the increased collagen content that was induced by bleomycin in this model. Analyses of Masson's Trichrome stained sections showed that pinocembrin treatment significantly reduced the connective tissue content in lung segments exposed to bleomycin when compared to bleomycin-infused lungs that did not receive pinocembrin. The striking anti-inflammatory and modest anti-fibrotic remodelling effects of pinocembrin administration were likely linked to the compound's ability to improve lung pathology and functional compliance in this animal model of pulmonary fibrosis. [ABSTRACT FROM AUTHOR]

Ureolysis-driven microbially induced carbonate precipitation (MICP) is a naturally occurring process facilitated through microbial activities and biogeochemical reactions to produce calcium carbonate (CaCO3) mineral. MICP serves as an alternative ground improvement binder method to conventional technologies which is sustainable, requires low energy for its treatment process, results in a minimal carbon footprint and could offer economic benefits. In the last two decades, MICP has drawn great interest from the scientific community because of its practicality to stabilize granular soils, repair concrete cracks and remediate heavy metals. To obtain successful MICP application, it is vital to understand the conditions that favor its process. This paper, therefore, provides an overview of literature on CaCO3 precipitation mediated by ureolysis-driven MICP and its mechanism. The review includes a discussion on sources of urease enzyme from microorganisms used to induce CaCO3 crystal formation required for implementation of MCIP for ground improvement. Moreover, the key factors that influence the outcome of MICP and bio-engineering testing methods typically used to evaluate MICP performance are also highlighted. Finally, this review also provides insight on the current drawbacks (i.e. ammonium production, scale-up bioprocess and treatment cost) affecting MICP technology and recommendations for future consideration. [ABSTRACT FROM AUTHOR]

The elimination of spore-forming bacteria is not guaranteed by current pasteurisation processes and is a challenging problem for the dairy industry. Given that Bacillus cereus sensu lato (B. cereus group) is an important foodborne pathogen and spoiler in the dairy industry, this study aimed at evaluating the prevalence and characteristics of B. cereus group in raw and pasteurised milk samples collected in Victoria, Australia. Isolated B. cereus group were tested for antimicrobial susceptibility, biofilm formation and virulence properties. Genetic diversity was assessed using ERIC-PCR. Proteomic profiling using MALDI-TOF MS and chemical profiling using Fourier-transform infrared (FTIR) spectroscopy were also applied for clustering of the isolates. Results showed 42.3% of milk samples contained B. cereus group, with a higher contamination level for pasteurised milk. Virulence studies identified genes nheA, nheB, hblA and nheC in most isolates and cyk gene in 46% of all isolates. Antimicrobial susceptibility testing showed a high prevalence of resistance towards ampicillin, ceftriaxone and penicillin. The biofilm-forming capacity of our isolates showed that most (53.7%) had the ability to form a biofilm. Genetic profiling using ERIC-PCR placed most B. cereus group isolates from pasteurised milk in the same cluster, indicating that they probably originated from a similar source. Raw milk isolates showed greater diversity indicating various sources. FTIR spectroscopy showed high agreement with genetic profiling. In contrast, low agreement between proteomic (MALDI-TOF MS) and genetic typing was observed. The present study showed that the FTIR spectroscopy could be adopted as a rapid tool for the typing of B. cereus group. Overall, the virulence and antimicrobial resistance characteristics, together with the ability of isolates to produce biofilm, indicate the importance of B. cereus group in the Australian dairy industry. [ABSTRACT FROM AUTHOR]

Oxaliplatin is a platinum-based chemotherapeutic used for cancer treatment. Its use associates with peripheral neuropathies and chronic gastrointestinal side-effects. Oxaliplatin induces immunogenic cell death by provoking the presentation of damage associated molecular patterns. The damage associated molecular patterns high-mobility group box 1 (HMGB1) protein exerts pro-inflammatory cytokine-like activity and binds to toll-like receptors (namely TLR4). Gastrointestinal microbiota may influence chemotherapeutic efficacy and contribute to local and systemic inflammation. We studied effects of oxaliplatin treatment on 1) TLR4 and high-mobility group box 1 expression within the colon; 2) gastrointestinal microbiota composition; 3) inflammation within the colon; 4) changes in Peyer’s patches and mesenteric lymph nodes immune populations in mice. TLR4+ cells displayed pseudopodia-like extensions characteristic of antigen sampling co-localised with high-mobility group box 1 -overexpressing cells in the colonic lamina propria from oxaliplatin-treated animals. Oxaliplatin treatment caused significant reduction in Parabacteroides and Prevotella1, but increase in Prevotella2 and Odoribacter bacteria at the genus level. Downregulation of pro-inflammatory cytokines and chemokines in colon samples, a reduction in macrophages and dendritic cells in mesenteric lymph nodes were found after oxaliplatin treatment. In conclusion, oxaliplatin treatment caused morphological changes in TLR4+ cells, increase in gram-negative microbiota and enhanced HMGB1 expression associated with immunosuppression in the colon. [ABSTRACT FROM AUTHOR]

Interest in endophytes as natural sources for new medicines was inspired by the discovery of paclitaxel-producing endophytic fungi. This study investigated the anti-cancer activity of extracts of endophytes isolated from two Australian plants, Eremophila longifolia (EL) and Eremophila maculata (EM). Endophytes were isolated from surface-sterilised leaf tissue, grown as pure cultures and identified by sequencing of Internal Transcribed Spacer (ITS) regions of the ribosomal DNA. To determine cytotoxicity, two leukaemic (MOLT-4, T-cell leukaemia; PreB-697, Pre-B leukaemia), a lung cancer cell line (A549) and a normal human fibroblast cell line were treated with endophyte extracts to assess cytotoxicity in relation to alternariol monomethyl ether (AME) and alternariol (AOH). Endophyte extracts that showed cell cytotoxicity were analysed by UV-HPLC to determine the metabolites. Pure AME and AOH, three extracts form Alternaria sp. (EM-6, EM-7 and EM-9) and one from Preussia minima (EL-14) were cytotoxic to the cancer cell lines. All cytotoxic endophytes contained AME and AOH, the most cytotoxic endophyte EM-6 also contained two unique peaks. These data indicate that these four endophyte extracts may have anti-cancer properties due to the presence of AME and AOH; however, the unique compounds found in the EM-6 extract may be exclusively cytotoxic and warrant further investigation. [ABSTRACT FROM AUTHOR]

Refrigerated storage of raw milk is a prerequisite in dairy industry. However, temperature abused conditions in the farming and processing environments can significantly affect the microbiological quality of raw milk. Thus, the present study investigated the effect of different refrigeration conditions such as 2, 4, 6, 8, 10 and 12 °C on microbiological quality of raw milk from three different dairy farms with significantly different initial microbial counts. The bacterial counts (BC), protease activity (PA), proteolysis (PL) and microbial diversity in raw milk were determined during storage. The effect of combined heating (75 ± 0·5 °C for 15 s) and refrigeration on controlling those contaminating microorganisms was also investigated. Results of the present study indicated that all of the samples showed increasing BC, PA and PL as a function of temperature, time and initial BC with a significant increase in those criteria ≥6 °C. Similar trends in BC, PA and PL were observed during the extended storage of raw milk at 4 °C. Both PA and PL showed strong correlation with the psychrotrophic proteolytic count (PPrBC: at ≥4 °C) and thermoduric psychrotrophic count (TDPC: at ≥8 °C) compared to total plate count (TPC) and psychrotrophic bacterial count (PBC), that are often used as the industry standard. Significant increases in PA and PL were observed when PPrBC and TDPC reached 5 × 104 cfu/ml and 1 × 104 cfu/ml, and were defined as storage life for quality (SLQ), and storage life for safety (SLS) aspects, respectively. The storage conditions also significantly affected the microbial diversity, where Pseudomonas fluorescens and Bacillus cereus were found to be the most predominant isolates. However, deep cooling (2 °C) and combination of heating and refrigeration (≤4 °C) significantly extended the SLQ and SLs of raw milk. [ABSTRACT FROM PUBLISHER]

The application of metabolomics to biological samples has been a key focus in systems biology research, which is aimed at the development of rapid diagnostic methods and the creation of personalized medicine. More recently, there has been a strong focus towards this approach applied to non-invasively acquired samples, such as saliva and exhaled breath. The analysis of these biological samples, in conjunction with other sample types and traditional diagnostic tests, has resulted in faster and more reliable characterization of a range of health disorders and diseases. As the sampling process involved in collecting exhaled breath and saliva is non-intrusive as well as comparatively low-cost and uses a series of widely accepted methods, it provides researchers with easy access to the metabolites secreted by the human body. Owing to its accuracy and rapid nature, metabolomic analysis of saliva and breath (known as salivaomics and breathomics, respectively) is a rapidly growing field and has shown potential to be effective in detecting and diagnosing the early stages of numerous diseases and infections in preclinical studies. This review discusses the various collection and analyses methods currently applied in two of the least used non-invasive sample types in metabolomics, specifically their application in salivaomics and breathomics research. Some of the salient research completed in this field to date is also assessed and discussed in order to provide a basis to advocate their use and possible future scientific directions. [ABSTRACT FROM AUTHOR]

The broad-spectrum activity of antimicrobial peptides (AMPs) and low probability of development of host resistance make them excellent candidates as novel bio-control agents. A number of AMPs are found to be cationic, and a small proportion of these are tryptophan-rich. The puroindolines (PIN) are small, basic proteins found in wheat grains with proposed roles in biotic defence of seeds and seedlings. Synthetic peptides based on their unique tryptophan-rich domain (TRD) display antimicrobial properties. Bacterial endospores and biofilms are highly resistant cells, with significant implications in both medical and food industries. In this study, the cationic PIN TRD-based peptides PuroA (FPVTWRWWKWWKG-NH2) and Pina-M (FSVTWRWWKWWKG-NH2) and the related barley hordoindoline (HIN) based Hina (FPVTWRWWTWWKG-NH2) were tested for effects on planktonic cells and biofilms of the common human pathogens including Pseudomonas aeruginosa, Listeria monocytogenes and the non-pathogenic Listeria innocua. All peptides showed significant bactericidal activity. Further, PuroA and Pina-M at 2 × MIC prevented initial biomass attachment by 85-90% and inhibited >90% of 6-h preformed biofilms of all three organisms. However Hina, with a substitution of Lys-9 with uncharged Thr, particularly inhibited Listeria biofilms. The PIN based peptides were also tested against vegetative cells and endospores of Bacillus subtilis. The results provided evidence that these tryptophan-rich peptides could kill B. subtilis even in sporulated state, reducing the number of viable spores by 4 log units. The treated spores appeared withered under scanning electron microscopy. The results establish the potential of these tryptophan-rich peptides in controlling persistent pathogens of relevance to food industries and human health. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

BACKGROUND Ascomycetes are capable of considerable lignocellulose degradation. However, there is limited knowledge on the metabolic profile of their biomass degradation. Metabolomic studies are capable of providing important biochemical information to understand and characterise fungal biomass degradation mechanisms. RESULTS Winery biomass waste of Vitis vinifera var. Shiraz was subjected to Aspergillus niger mediated solid state fermentation for 8 days in 2H2O supplemented medium. Samples were collected every 24 h, freeze-dried and derivatized before GC-MS analysis. Covariance-inverse multivariate statistics were used to classify the most significant metabolites. Metabolite-flux profiling classified 37 unique metabolites in 18 different pathways leading to or from glycolysis-tricarboxylic acid pathways. The majority of the sugars were consumed during the first 4 days; this was in order to synthesize fatty acids, amino acids and secondary metabolites. Inhibition started at day 5, as indicated by the accumulation of sugars and the plateauing of N-acetyl glucosamine (a major fungal cell wall component). CONCLUSIONS A 4-day continuous yeast or mixed fungal fermentation will not only prevent product inhibition, but it will also aid in generating bio-ethanol. Inducing 2-keto-acid decarboxylases followed alcohol dehydrogenases at the onset of inhibition is predicted to aid in the generation of butanol isomers, which are considered valuable sources of fuel. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Background: Parasitic roundworms (nematodes) cause substantial morbidity and mortality in livestock animals globally, and considerable productivity losses to farmers. The control of these nematodes has relied largely on the use of a limited number of anthelmintics. However, resistance to many of these these anthelmintics is now widespread, and, therefore, there is a need to find new drugs to ensure sustained and effective treatment and control into the future. Methods: Recently, we developed a screening assay to test natural, plant extracts with known inhibitory effects against the free-living worm Caenorhabditis elegans. Using this assay, we assessed here the effects of the extracts on motility and development of parasitic larval stages of Haemonchus contortus, one of the most important nematodes of small ruminants worldwide. Results: The study showed that two of five extracts from Picria fel-terrae Lour. have a significant inhibitory effect (at concentrations of 3-5 mg/ml) on the motility and development of H. contortus larvae. Although the two extracts originated from the same plant, they displayed different levels of inhibition on motility and development, which might relate to the presence of various active constituents in these extracts, or the same constituents at different concentrations in distinct parts of the plant. Conclusions: These results suggest that extracts from P. fel-terrae Lour. have promising anthelmintic activity and that more broadly, plant extracts are a potential rich source of anthelmintics to combat helminthic diseases. [ABSTRACT FROM AUTHOR]

Drug-resistant microorganisms ('superbugs') present a serious challenge to the success of antimicrobial treatments. Subsequently, there is a crucial need for novel bio-control agents. Many antimicrobial peptides (AMPs) show a broad-spectrum activity against bacteria, fungi or viruses and are strong candidates to complement or substitute current antimicrobial agents. Some AMPs are also effective against protozoa or cancer cells. The tryptophan (Trp)-rich peptides (TRPs) are a subset of AMPs that display potent antimicrobial activity, credited to the unique biochemical properties of tryptophan that allow it to insert into biological membranes. Further, many Trp-rich AMPs cross bacterial membranes without compromising their integrity and act intracellularly, suggesting interactions with nucleic acids and enzymes. In this work, we overview some archetypal TRPs derived from natural sources, i.e., indolicidin, tritrpticin and lactoferricin, summarising their biochemical properties, structures, antimicrobial activities, mechanistic studies and potential applications. [ABSTRACT FROM AUTHOR]

BACKGROUND Recently, winery wastes have been classified as pollutants by the European Union and post-product processing is required to lower their hazards. Individual fungal enzymes have limited capacity so mixed fungal degradation combined with pre-treatment can decrease biomass recalcitrance for more efficient breakdown, overcoming these limitations. RESULTS Winery biomass degradation by a mixture of Trichoderma harzianum, Aspergillus niger, Penicillium chrysogenum and P. citrinum in submerged fermentation and solid state fermentation ( SSF) was evaluated. Higher cellulase and β-glucosidase activities were observed in SSF and submerged fermentation, respectively. Statistical modelling predicted the fungal percentage ratio of 60:14:4:2 for A. niger: P. chrysogenum: T. harzianum: P citrinum with a substrate:medium ratio of 0.39:1. Under the optimized conditions, cellulase, xylanase and β-glucosidase activities increased to 78.5, 3544.7 and 250.9 U mL−1, respectively. Cellulases and xylanases activities increased more than two-fold. Lignin degradation increased from 8% in submerged fermentation ( P. chrysogenum) to 17.9% under optimized conditions. Gas chromatography-mass spectrometry ( GC-MS) analysis identified 78 significant metabolites, of which stigmasterol, glycerol, maleic acid, xylitol and citric acid were generated by fungal degradation. CONCLUSIONS Enhanced degradation of winery-derived biomass was achieved using mixed fungal cultures. GC-MS analysis indicated the production of commercially important metabolites during the process. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

This paper illustrates the application of an untargeted metabolic profiling analysis of winery-derived biomass degraded using four filamentous fungi (Trichoderma harzianum, Aspergillus niger, Pénicillium chrysogenum and P. citrinum) and a yeast (Saccharomyces cerevisiae). Analysis of the metabolome resulted in the identification of 233 significant peak features [P < 0.05; fold change (FC) > 2 and signal-to-noise ratio >50] using gas chromatography-mass spectrometry followed by statistical chemometric analysis. Furthermore, A. niger and P. chrysogenum produced higher biomass degradation due to considerable β-glucosidase and xylanase activities. The major metabolites generated during fungal degradation which differentiated the metabolic profiles of fungi included sugars, sugar acids, organic acids and fatty acids. Although, P. chrysogenum could degrade hemicelluloses due to its high β-glucosidase and xylanase activities, it could not utilize the resultant pentoses, which A. niger and P. citrinum could do efficiently, thus indicating a need of mixed fungal culture to improve the biomass degradation. Saccharomyces cerevisiae, a non-cellulose degrader, exhibited sugar accumulation during the fermentation. Penicillium chrysogenum was observed to degrade about 2% lignin, a property not observed in other fungi. This study emphasized the differential fungal metabolic behavior and demonstrated the potential of metabolomics in optimizing degradation or manipulating pathways to increase yields of products of interest. [ABSTRACT FROM AUTHOR]

Background: Plant-derived compounds have been used clinically to treat type 2 diabetes for many years as they also exert additional beneficial effects on various other disorders. The aim of the present study was to investigate the possible mechanism of anti-diabetic activity of twelve (seven Australian Aboriginal and five Indian Ayurvedic) plant extracts. Methods: The ethanolic plant extracts were investigated for glucose uptake and adipogenesis in murine 3T3-L1 adipocytes. Cytotoxicity studies were also carried out against two cancerous cell lines, HeLa and A549, to investigate the potential anti-cancer activities of the extracts. Results: Of the seven Australian Aboriginal plant extracts tested, only Acacia kempeana and Santalum spicatum stimulated glucose uptake in adipocytes. Among the five Indian Ayurvedic plant extracts, only Curculigo orchioides enhanced glucose uptake. With respect to adipogenesis, the Australian plants Acacia tetragonophylla, Beyeria leshnaultii and Euphorbia drumondii and the Indian plants Pterocarpus marsupium, Andrographis paniculata and Curculigo orchioides reduced lipid accumulation in differentiated adipocytes. Extracts of Acacia kempeana and Acacia tetragonophylla showed potent and specific activity against HeLa cells. Conclusions: The findings suggest that the plant extracts exert their anti-diabetic properties by different mechanisms, including the stimulation of glucose uptake in adipocytes, inhibition of adipogenesis or both. Apart from their anti-diabetic activities, some of the extracts have potential for the development of chemotherapeutic agents for the treatment of cervical cancer. [ABSTRACT FROM AUTHOR]

Endophytes are recognised as potential sources of novel secondary metabolites, including enzymes and drugs, with applications in medicine, agriculture and industry. There is a growing need for new enzymes, including proteases, for use in industry that can function under a variety of conditions. In this study, three fungal endophytes ( Alternaria alternata, Phoma herbarum and an unclassified fungus), were isolated from the Australian native plant, Eremophilia longifolia, and assessed for production of proteases. The lyophilised growth media obtained after fungal fermentation were analysed for protease production using enzyme activity assays. Protease production was optimised by assessing the effects of temperature, pH, carbon source and nitrogen source on activity. A. alternata showed the greatest protease activity in a wide range of pH (3-9). The broadest activity between 9 and 50 °C was observed at pH 7, suggesting a neutral protease. Overall, the optimum conditions were 37 °C and pH 7 with a maximum specific activity value of 69.86 BAEE units/mg. The characteristics demonstrated by this fungal endophyte showed that it is a potential source of an enzyme with particular application in the dairy industry. However, further studies of the tolerance to higher temperatures and pH will indicate whether the enzyme is suitable to such applications. [ABSTRACT FROM AUTHOR]

Objectives: Heparan sulphate mimetics, particularly heparin (Hep), have previously been shown to considerably inhibit infection of enterovirus 71 (EV71) in Vero cells. Therefore, in this study, a genome-wide DNA microarray was performed to gain insight into the mechanism(s) of action of Hep against infection of a human neural cell line, SK-N-SH, with a clinical strain of EV71. Methods: This study focused on a selection of EV71-induced genes whose expression profiling was exclusively affected by the antiviral activity of Hep. The selection procedure was performed through a statistical multi-level comparison with the following controls: negative control cells, compound control (cells treated with Hep only), virus control (cells treated with virus only) and treatment control (EV71-infected cells treated with Hep). Results: Overall, of more than 30,000 genes studied, 14 well-known annotated genes were selected that may be targets for the antiviral activity of Hep against EV71 infection in neural cells. For most of these genes, Hep appeared to modulate the impact of EV71 infection on the expression pattern of the genes. Conclusions: The findings of this research may provide initial assistance in new directions for studies to design molecular drug targets against EV71 infection. © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background Environmental screening programs are used to find new enzymes that may be utilized in large-scale industrial processes. Among microbial sources of new enzymes, the rationale for screening fungal endophytes as a potential source of such enzymes relates to the hypothesised mutualistic relationship between the endophyte and its host plant. There is a need for new microbial amylases that are active at low temperature and alkaline conditions as these would find industrial applications as detergents. Results An α-amylase produced by Preussia minima, isolated from the Australian native plant, Eremophilia longifolia, was purified to homogeneity through fractional acetone precipitation and Sephadex G-200 gel filtration, followed by DEAE-Sepharose ion exchange chromatography. The purified α-amylase showed a molecular mass of 70 kDa which was confirmed by zymography. Temperature and pH optima were 25°C and pH 9, respectively. The enzyme was activated and stabilized mainly by the metal ions manganese and calcium. Enzyme activity was also studied using different carbon and nitrogen sources. It was observed that enzyme activity was highest (138 U/mg) with starch as the carbon source and L-asparagine as the nitrogen source. Bioreactor studies showed that enzyme activity was comparable to that obtained in shaker cultures, which encourages scale-up fermentation for enzyme production. Following in-gel digestion of the purified protein by trypsin, a 9-mer peptide was sequenced and analysed by LC-ESI-MS/MS. The partial amino acid sequence of the purified enzyme presented similarity to α-amylase from Magnaporthe oryzae. Conclusions The findings of the present study indicate that the purified α-amylase exhibits a number of promising properties that make it a strong candidate for application in the detergent industry. To our knowledge, this is the first amylase isolated from a Preussia minima strain of endophytic origin. [ABSTRACT FROM AUTHOR]

Solid lipid nanoparticles (SLNs) are a well-tolerated lipid carrier system due to the employment of a physiological and/or biodegradable lipid matrix. Physicochemical properties such as particle size, polydispersity index (PI) and zeta potential are SLN quality response parameters. Increased particle size is a good indicator of in-vitro instability. This work focuses on the importance of selecting the lipid matrices and excipients that can achieve the particle size and stability required if such formulations are to be utilised in the pharmaceutical market. With the aim of understanding the influence of variation in SLN composition (lipid and emulsifier concentration), a Taguchi model of experimental design was applied. Tested factors included the concentration of lipid (stearic acid) and the concentration of Tween®20. SLNs were successfully prepared by a microemulsion-based technique. Based on the hydrophilic lipophilic balance (HLB), different combinations of emulsifiers/co-emulsifiers (Tween®20/Span®20, Tween®20/Span®80, Tween®20/n-butanol, and Tween®20/iso-propanol) were also used to control the physicochemical properties of SLNs. The influence of pH (addition of HCl or NaOH) and electrolyte (addition of NaCl), both during and after the preparation, were also investigated on selected SLN formulations. Slightly polydispersed (PI < 0.3) nanoparticles with a particle size < 450 nm and zeta potential range of +5 to -50 mV were developed. Physical stability of optimised stearic-acid based SLNs over 2 months were assessed by particle size measurement. SLNs were stable when refrigerated. These results suggest that thoughtful selection of lipid and lipid excipients is essential for successful preparation and physical stability of SLNs. This study facilitates the preliminary physicochemical characterisation for favourable encapsulation of lipophilic and hydrophilic drugs. [ABSTRACT FROM AUTHOR]

The emergence of drug resistant variants of the influenza virus has led to a need to identify novel and effective antiviral agents. As an alternative to synthetic drugs, the consolidation of empirical knowledge with ethnopharmacological evidence of medicinal plants offers a novel platform for the development of antiviral drugs. The aim of this study was to identify plant extracts with proven activity against the influenza virus. Extracts of fifty medicinal plants, originating from the tropical rainforests of Borneo used as herbal medicines by traditional healers to treat flu-like symptoms, were tested against the H1N1 and H3N1 subtypes of the virus. In the initial phase, in vitro micro-inhibition assays along with cytotoxicity screening were performed on MDCK cells. Most plant extracts were found to be minimally cytotoxic, indicating that the compounds linked to an ethnomedical framework were relatively innocuous, and eleven crude extracts exhibited viral inhibition against both the strains. All extracts inhibited the enzymatic activity of viral neuraminidase and four extracts were also shown to act through the hemagglutination inhibition (HI) pathway. Moreover, the samples that acted through both HI and neuraminidase inhibition (NI) evidenced more than 90% reduction in virus adsorption and penetration, thereby indicating potent action in the early stages of viral replication. Concurrent studies involving Receptor Destroying Enzyme treatments of HI extracts indicated the presence of sialic acid-like component(s) that could be responsible for hemagglutination inhibition. The manifestation of both modes of viral inhibition in a single extract suggests that there may be a synergistic effect implicating more than one active component. Overall, our results provide substantive support for the use of Borneo traditional plants as promising sources of novel anti-influenza drug candidates. Furthermore, the pathways involving inhibition of hemagglutination could be a solution to the global occurrence of viral strains resistant to neuraminidase drugs. [ABSTRACT FROM AUTHOR]