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The objective of this study was to investigate the extent of contamination of some of the most used paper denominations of the Egyptian currency (25 PT). Sixty-nine bills in circulation were collected from November 2003 through January 2004. A swab from each bill was cultured on nutrient agar and incubated at 37°C for 48?h. Results showed that over 65% of these bills had a bacterial count above 5.0?cm 2 . A preliminary identification of organisms present on these paper notes was done using selected Petri dishes with well-defined colonies. [ABSTRACT FROM AUTHOR]

As a representative colorimetic biosnesor, paper-based LFSA have emerged as a promising and robust tool that can easily and instansly detect the presence of target biological components in food sample. Recently, LFSAs have gained a considerable attention as an alternative method for rapid diagnosis of foodborne pathogens to the conventional culture-based assays such as plate counting and PCR. One major drawback of the current LFSAs for the detection of pathogenic bacteria is the low sensitivity, limiting its practical applications in POCT. Not like many other protein-based biomarkers that are present in nM or pM range, the number of pathogenic bacteria that cause disease can be as low as few CFU/ml. Here, we review current advances in LFSAs for the detection of pathogenic bacteria in terms of chromatic agents and analyte types. Furthermore, recent approaches for signal enhancement and modifications of the LFSA architecture for multiplex detection of pathogenic bacteria are included in this review, together with the advantages and limitations of each techniques. Finally, the technological challenges and future prospect of LFSA-based POCT for the detection of pathogenic bacteria are discussed. [ABSTRACT FROM AUTHOR]

Gut dysbiotic symptoms with a characteristic clinical pattern have been known for many years. In the 1970s Truss advanced the theory that the syndrome is caused by Candida albicans . This has generated much medical controversy. In some centres the attribution has caused rejection of the syndrome itself. A number of studies have demonstrated organic changes in sufferers of what the author prefers to call fungal-type dysbiosis; however, over the past twenty years convincing data have not been published identifying causal yeasts. There is a further problem with a name involving Candida in that it may cause confusion with established syndromes known to be associated with that organism. This paper will review the literature and advance an alternative hypothesis that the syndrome could have a bacterial rather than a yeast cause. [ABSTRACT FROM AUTHOR]

Gut dysbiotic symptoms with a characteristic clinical pattern have been known for many years. In the 1970s Truss advanced the theory that the syndrome is caused by Candida albicans. This has generated much medical controversy. In some centres the attribution has caused rejection of the syndrome itself. A number of studies have demonstrated organic changes in sufferers of what the author prefers to call fungal-type dysbiosis; however, over the past twenty years convincing data have not been published identifying causal yeasts. There is a further problem with a name involving Candida in that it may cause confusion with established syndromes known to be associated with that organism. This paper will review the literature and advance an alternative hypothesis that the syndrome could have a bacterial rather than a yeast cause. [ABSTRACT FROM AUTHOR]

Microbial-induced carbonate precipitation (MICP) technology has gained significant traction as an eco-friendly, cost-effective, and intelligent self-healing method for concrete cracks. The harsh service environment and high alkalinity of cement matrices have posed a significant challenge to the survival and growth of bacteria, which is crucial for the success of MICP technologies in concrete components. This article aims to present an up-to-date overview of the current research status of self-healing concrete cracks utilizing MICP technology. Specifically, it comprehensively reviews the selection of mineralization repair systems, encompassing repair mechanisms, effects, processes, nutrient addition sequences, and carrier selection. Furthermore, various characterization methods for evaluating the self-healing ability of concrete are explored, accompanied by an in-depth analysis of practical applications of self-healing concrete. Finally, this paper highlights the pressing issues facing this technology while outlining promising directions for future advancement. [ABSTRACT FROM AUTHOR]

The use of fossil fuels leads to environmental contamination during their extraction, processing and distribution. Microbial biodegradation provides a sustainable method for cleaning contaminated areas which follows the principles of sustainability. This paper presents the dynamics of biodegradation of hydrocarbon fractions of diesel oil, using Planomicrobium sp. and Rhodococcus sp. isolated from petroleum-contaminated sites. GC–MS analysis was employed to analyse abundances of the specific compounds such as n-alkanes, isoprenoids, sesquitepranes, hopanes, steranes and aromatic compounds (naphthalene and its methylated homologues, phenanthrene and anthracene and their methylated homologues, and dibenzothiophene and its methylated homologues). The obtained results showed that after 30 days of biodegradation of diesel, a significant degradation was achieved, with almost complete degradation of n-alkanes and a decrease in the amount of sesquiterapanes. Rhodococcus sp. had a higher efficiency in degradation of n-alkanes, while Planomicrobium sp. had a higher efficiency in the degradation of branched hydrocarbons. Both strains showed high activity in the biodegradation of sesquitepranes and demonstrate ability to degrade methylated phenanthrenes. Additionally, dimethyl-dibenzothiophenes were almost completely degraded and removed from the system. This study presents the first comprehensive report on the GC–MS analysis of the diesel biodegradation pattern of the Planomicrobium sp., compared with the well-established Rhodococcus sp. [ABSTRACT FROM AUTHOR]

The extensive use of organic chemicals has resulted in the widespread distribution of hydrocarbon contaminants (HCs) in many ecosystems on a global scale. Many subterranean ecosystems can rapidly become anaerobic or even methanogenic following hydrocarbon contamination. Bacteria and archaea dominate communities in such systems and mediate the syntrophic processes that transform HCs into methane (CH4). The resulting CH4 is oxidized by anaerobic bacteria and archaea, either jointly or individually, in the presence of electron acceptors (e.g., sulfate, nitrate, nitrite, manganese, or ferric iron), a process that reduces CH4 emissions and, as a result, contributes to climate change mitigation. Although the possibility of the syntrophy of bacteria and archaea in the anaerobic transformation of HCs and methane oxidation is widely established, the specific pathways and syntrophic taxa involved are poorly understood. This paper reviews the syntrophy of bacteria and archaea in anaerobic HC degradation, with a focus on methanogenic processes. In addition, we discuss the role of bacteria and archaea in the anaerobic oxidation of methane (AOM) and its environmental significance. Given that much of the biotransformation of HCs driven by methanogenic and methanotrophic processes remains unknown, we propose a way forward to discover novel syntrophic partners and metabolic pathways in such anoxic systems. [ABSTRACT FROM AUTHOR]

The paper reviewed the current perspectives on the development of carbon dioxide (CO2) sequestration through its process conversion into calcite. The process occurs in either geological or biological systems. However, geological sequestration is an expensive process, which is slow in comparison to bio-sequestration. Recently, the bio-sequestration of atmospheric CO2 into the soil using microorganisms such as algae has been investigated. However, the algae cannot be used in the bio-concrete due to their nature as phototrophic organisms. In contrast, bacteria are the most potent organisms in bio-concrete technology. The use of bacterial species in the bio-aerated concrete bricks (B-ACB) and its potential to bio-sequestrate CO2 represents a future strategy to reduce high CO2 pollution. Bacterial cells can capture CO2 by accelerating the carbonation processes, which convert CO2 into calcium carbonate (CaCO3) via carbon anhydrase and urease enzymes. The present paper aimed to highlight and discuss the applicability of bacteria in the B-ACB for capturing and storing CO2. It is evident from the literature that the new trends to use bio-concrete might contribute to the reduction of CO2 by accelerating the carbonation process and strengthening the B-ACB. [ABSTRACT FROM AUTHOR]

Spirulina species are photosynthetic and filamentous bacteria, commonly called 'blue-green microalgae'. Spirulina has a high nutrient content. It contains 60–70% protein with all essential amino acids present, and is rich in several vitamins, minerals, and bioactive compounds. Spirulina is also rich in essential fatty acids, and antioxidants. This rich nutritional content provides to Spirulina several health benefits including antioxidant, anti-inflammatory, immunomodulation, and insulin-sensitizing properties as well as positive effects in various diseases which could be also interesting for athletes. This paper mainly aims to review the interest and effects of Spirulina supplementation in athletes at rest, and in relation to exercise/training. Spirulina's biochemical composition, health properties/effects in humans, and effects in athletes including nutritional status, body composition, physical performance and intense exercise-related disorders were discussed in this review. Literature data showed that Spirulina seems to have positive effects on body composition especially in overweight and obese subjects which could not be the case in other pathologies and athletes. Spirulina appears to be also effective in improving aerobic fitness especially in untrained and moderately trained subjects. Results reported in the literature suggest that Spirulina may improve strength and power performance despite the minor or no significant effects in highly trained subjects. Most studies have shown that Spirulina improves antioxidant status, prevents and accelerates the recovery of exercise-induced lipid peroxidation, muscle damage and inflammation in trained and untrained subjects. Taken together, the results from these studies are encouraging and may demonstrate the potential benefits of Spirulina supplementation in athletes despite methodological differences. [ABSTRACT FROM AUTHOR]

Goa is situated in the northwestern part of the Western Dharwar Craton (WDC) which is Asia's major metallogenic province. The iron ore of Goa is associated with greenstone and occurs as bands, reefs, and lenses of Banded Hematite Quartzite (BHQ) and Banded Magnetite Quartzite (BMQ) none of these are explored for geo-microbiological dimensions, such as detection of microbioform Gold. The presence of metalliferous WDC in Goa affords sampling of auriferous materials from mining area having hitherto BHQ at latitude 15°29′54″ N and longitude 74° 03′44″ E) and BMQ at latitude 15°24′12″ N and longitude 74° 09′31″ E were collected, surface sterilized and drilled with a sterile driller to get the endolithic material under sterile conditions and sent for metagenomic analysis using Oxford nanopore sequencing. Both the samples showed the presence of microorganisms with Archea, such as Haloferax, Nitrososphaera, and Eubacteria, i.e., Bacillus, Ralstonia, Cupriavidus, Burkholderia, and Acetobacter. The traditional model of Banded Iron Deposition assumes precipitation by the oxidation of hydrothermal Fe (II), either via abiotic oxidation or biotic oxidation through chemo lithotrophic Eubacteria, such as cyanobacteria which produce oxygen. This paper reports the diversity and the presumptive role of these microorganisms in the biogeochemical cycling of metals, such as Fe, Mn, and gold (Au). [ABSTRACT FROM AUTHOR]

Acid-resistant bacteria are more and more widely used in industrial production due to their unique acid-resistant properties. In order to survive in various acidic environments, acid-resistant bacteria have developed diverse protective mechanisms such as sensing acid stress and signal transduction, maintaining intracellular pH homeostasis by controlling the flow of H+, protecting and repairing biological macromolecules, metabolic modification, and cross-protection. Acid-resistant bacteria have broad biotechnological application prospects in the food field. The production of fermented foods with high acidity and acidophilic enzymes are the main applications of this kind of bacteria in the food industry. Their acid resistance modules can also be used to construct acid-resistant recombinant engineering strains for special purposes. However, they can also cause negative effects on foods, such as spoilage and toxicity. Herein, the aim of this paper is to summarize the research progress of molecular mechanisms against acid stress of acid-resistant bacteria. Moreover, their effects on the food industry were also discussed. It is useful to lay a foundation for broadening our understanding of the physiological metabolism of acid-resistant bacteria and better serving the food industry. [ABSTRACT FROM AUTHOR]

In this paper, three effective toluene-degrading bacteria were obtained through acclimation and screening by using landfill leachate as the initial liquid strain. The three obtained bacteria were denoted as J1, J2 and J3, and identified as Pseudomonas, Bacillus and Staphylococcus, respectively. We then identified the optimal combination of these toluene-degrading bacteria in the laboratory. The combination of J1 + J3 (1:1) exhibited the highest toluene removal efficiency (RE). A vertical bio-trickling filter (BTF) packed with ceramsite was started by inoculation with the effective combination. The performance of the BTF in treating toluene under various operating conditions was investigated. After 17 days of operation, the toluene RE reached about 90% and the maximum elimination capacity reached 42.0 g m−3 h−1. The scanning electron microscope (SEM) showed that after the successful start-up of the BTF, the biofilm on the packing surface primarily consisted of Bacillus and Staphylococcus. During the stable state, the RE of the BTF was maintained above 80%, the shortest empty bed residence time was 34 s and toluene concentrations ranged between 300 and 800 mg m−3. The results indicate that the BTF started using the effective combination of bacteria described here is robust. This paper also provides a preliminary analysis of the mechanism of microbial degradation of pollutants in the BTF. [ABSTRACT FROM AUTHOR]

Mohangic acids are a class of p-aminoacetophenonic acids that contain a conjugated triene or diene moiety. Herein, this paper reports two new mohangic acids E and F (1-2) together with a known compound mohangic acid A (3), which were isolated from the deep-sea sediment-derived bacteria Alcanivorax dieselolei BC-5. The structures of 1 and 2 were established by HRESIMS, 1 D and 2 D NMR, and IR spectroscopy. [ABSTRACT FROM AUTHOR]

Although not as well studied as the bacterial component of the human microbiota, the commensal fungi or mycobiota play important roles in maintaining our health by augmenting our immune system. This mycobiota is also associated with various fatal diseases like opportunistic mycoses, and even cancer, with different cancers having respective type-specific mycobiota. The different fungal species which comprise these different intratumoral mycobiota play important roles in cancer progression. The aim of this review paper is to decipher the association between mycobiota and cancer, and shed light on new avenues in cancer diagnosis, and the development of new anti-cancer therapeutics. [ABSTRACT FROM AUTHOR]

AbstractPhages play a critical role in the assembly and regulation of fermented food microbiome through lysis and lysogenic lifestyle, which in turn affects the yield and quality of fermented foods. Therefore, it is important to investigate and characterize the diversity and function of phages under complex microbial communities and nutrient substrate conditions to provide novel insights into the regulation of traditional spontaneous fermentation. Viral metagenomics has gradually garnered increasing attention in fermented food research to elucidate phage functions and characterize the interactions between phages and the microbial community. Advances in this technology have uncovered a wide range of phages associated with the production of traditional fermented foods and beverages. This paper reviews the common methods of viral metagenomics applied in fermented food research, and summarizes the ecological functions of phages in traditional fermented foods. In the future, combining viral metagenomics with culturable methods and metagenomics will broaden the scope of research on fermented food systems, revealing the complex role of phages and intricate phage–bacterium interactions. [ABSTRACT FROM AUTHOR]

Natural environments contain a variety of microorganisms, of which, a limited number are able to develop bioremediation process. The main goal of the present paper was to perform microbiological investigations to culturable bacteria isolated from uranium ore samples from Aborshid Egypt, and characterize their response to 15 antibiotics and 10 heavy metals beside uranium. Among the potential environmental isolates, there was no detection of any acquired antibiotic resistance, which supports the idea that their resistance mechanisms are mainly intrinsic. On the contrary, the potentially pathogenic isolates presented a broad diversity of acquired antibiotic resistance toward different antibiotic classes. Furthermore, results revealed a varying response of the ore bacteria to the tested heavy metals. All isolates showed multiple metal resistances toward 10 heavy metals, with MIC ranging from 50 to 1000ppm. We found that optimum temperature for growth of bacteria in general ranges from 30 to 50 °C and bio-sorption of metal increased with increasing pH from 1.0 to 5.0, then decreased upon further increase to 7.0. The decrease in the sorption efficiency at pH higher than 5.0 may be due to the precipitation as hydroxide. We found possible correlation between antibiotic resistance and heavy-metal resistance patterns of Escherichia coli strains isolated from uranium ore; the most potent of the strains in both groups were resistant to Pb, Ni, Cu and Zn. It was concluded that highly metal-resistant bacteria could be used with potential application for treatment of wastewaters. [ABSTRACT FROM AUTHOR]

The modeling of the response of living organisms to a change in environment is an important issue of current interest. An example is the effect of ultraviolet radiation on biological systems. In this paper, molecular and analytical identification of Pseudomonas isolate were reported. Then, swarmer Pseudomonas cells were exposed to UVc radiations. The spatiotemporal response of swarmer Pseudomonas, to UVc exposure, was followed. Observing alterations in bacterial membrane integrity by electron microscopy can help to clarify the detailed mechanisms of resistance to UVc. The most evident changes were related to membrane structures. In the cytoplasm, the main finding was the appearance of round mesosomes as intracellular bilayered membranes. Another impact of UVc on Pseudomonas was evident from the appearance of additional membrane structures. In accordance with the viability results, UVc-induced ultrastructural changes of Pseudomonas membrane structures were identified, resulting in cell death, through a multistage model of UVc inactivation. [ABSTRACT FROM AUTHOR]

Sulphate-reducing bacteria (SRB) are known to cause severe corrosion of steel structures in various industries, resulting in significant economic and environmental consequences. This review paper critically examines the impact of SRB-induced corrosion on steel, including the formation of SRB biofilms, the effect on different types of steel, and the various models developed to investigate this phenomenon. The role of environmental factors in SRB-induced corrosion, molecular techniques for studying SRBs, and strategies for mitigating corrosion are discussed. Additionally, the sustainability implications of SRB-induced corrosion and the potential use of alternative materials were explored. By examining the current state of knowledge on this topic, this review aims to provide a comprehensive understanding of the impact of SRB-induced corrosion on steel and identify opportunities for further research and development. [ABSTRACT FROM AUTHOR]

On the base of the existing research study, a multi-period, multi-product, multi-supplier, single-manufacture, and multi-distributor supply chain model is considered in the paper. In the three-echelon model, a variety of decision-making activities involved in the procurement, production and distribution process are integrated at the operational level, giving rise to the non-deterministic polynomial-time hard computational complexity for model optimisation. For tackling the difficult model, this paper proposes a new optimisation method called guided chemotaxis-based bacterial colony algorithm, characterised by centre learning communication mechanism. More specifically, centre learning communication mechanism, where all the bacteria are enforced to learn towards the centre position of the swarm, is designed for the global exploration ability of algorithm. Chemotaxis, which guides the bacterium to fine-tune the solution in an increasingly favourable fitness landscape, is used to enhance the local exploitation ability of algorithm. Numerical experiments on a variety of simulated scenarios show the effectiveness and efficiency of the proposed algorithm in terms of both quality solution and computational time, by comparing it with some existing state-of-the-art solution approaches. [ABSTRACT FROM AUTHOR]

This paper examines the effects of hydroxyapatite (HA) and bone- particle (BP) doping on the removal of fluoride and bacteria by ceramic water filters (CWFs). The CWFs were produced by mixing clay, sieved sawdust, and either HA or BPs in a weight ratio of 30:50:20 and sintered at 850°C or 900°C to produce micro-/ nano-porous structures that remove microbial pathogens (by geometric occlusion) and fluoride (by adsorption) from contaminated water. The HA-doped filters exhibited similar flow characteristics to the BP-doped filters. However, BP-doped CWFs were more effective in removing fluoride and microbial pathogens (such as E. coli) from contaminated water than HA-doped filters. The water flow rates and fluoride removal depended on sintering temperature, with CWFs sintered at 850°C enabling faster flow rates of 2.2Lh−1 and higher fluoride removal of 2.74 mol.cm−2 than the CWFs sintered at 900°C. Fluoride removal by the HA- and BP-doped filters was well characterized by Freundlich isotherms that reveal the occurrence of spontaneous but heterogeneous adsorption. The implications of the results are discussed for the design of point-of-use CWFs for the removal of fluoride and microbial pathogens. [ABSTRACT FROM AUTHOR]

A new method for curing electrolytic manganese residue (EMR) using the biocarbonization of reactive MgO (r-MgO) is presented in this paper. This method uses microbial technology to provide CO2 to react with r-MgO then strengthen the EMR and reduce its heavy-metal content, which combines the advantage of r-MgO solidification technology and microbial technology. Several parameters include the content of r-MgO and urea, initial moisture content, and age that affect the moisture content, dry density, pH, unconfined compressive strength, stress–strain curve, and microstructure of solidified EMR are studied, and the solidification mechanism of EMR using the biocarbonization of r-MgO is discussed. The results show that the hydration of r-MgO generates brucite can reduce the moisture content and increase the dry density and pH. The CO2 produced by the hydrolysis of urea with bacteria reacts with brucite to produce nesquehonite, hydromagnesite, and other carbonized products that further reduce the moisture content and increase the dry density. This process can bridge particles and fill pores, consequently improving the EMR strength. At early age, the biocarbonated EMR samples can reach 5.22 MPa at 12 h. This shows the biocarbonization of r-MgO is effective for solidifying EMR. [ABSTRACT FROM AUTHOR]

Bacterial invasion of the periodontal tissues has been suggested as a relevant step in the etiopathogenesis of periodontal disease. However, its exact importance remains to be defined. The present systematic review assessed the scientific evidence concerning the relationship between the quality or quantity of periodontal microbiota in periodontal tissues and development of periodontal disease. The databases Medline-PubMed, Cochrane-CENTRAL, ISI Web of Knowledge and SCOPUS were searched, up to January 2014. Studies that reported evaluation of periodontal pathogens invasion on human tissues were selected. The screening of 440 title/abstracts elected 26 papers for full-text reading. Twenty three papers were subsequently excluded because of insufficient data or a study protocol not related to the objectives of this systematic review. All included studies were case-control studies that evaluated intracellular or adherent bacteria to epithelial cells from periodontal pockets versus healthy sulci. Study protocols presented heterogeneity regarding case and control definitions and methodological approaches for microbial identification. No consistent significant differences were found related to the presence/absence or proportion of specific periopathogens across the studies, as only one study found statistically significant differences regarding the presence of A. actinomycetemcomitans (p = 0.043), T. forsythia (P < 0.001), P. intermedia (P < 0.001), C. ochracea (P < 0.001) and C. rectus (P = 0.003) in epithelial cells from periodontal pockets vs. healthy sulci. All studies reported a larger unspecific bacterial load in or on the epithelial cells taken from a diseased site compared to a healthy sulcus. The current available data is of low to moderate quality and inconsistent mainly due to study design, poor reporting and methodological diversity. As so, there is insufficient evidence to support or exclude the invasion by periodontal pathogens as a key step in the etiopathogenesis of periodontal disease. Further research is needed. [ABSTRACT FROM AUTHOR]

Highly active and stable biocatalysts are the prerequisite for industrial scale application of the biodesulfurization process. Scientists are making efforts for increasing the desulfurizing activity of native strains by employing various genetic engineering approaches. Nevertheless, the achieved desulfurization rate is lower than the industrial requirements. Thus, there is a dire need to use efficient genetic tools for precise genome editing of desulfurizing bacteria for enhanced efficiency. In comparison to the previously used genetic engineering tools the newly developed CRISPR-Cas is a more efficient and simple genetic tool that has been successfully applied for targeted genome modification of eukaryotes as well as prokaryotes. In this paper, we have reviewed the approaches, previously used to enhance the biodesulfurization rates of the sulfur metabolizing microorganisms and have discussed the potential of CRISPR-Cas systems in engineering desulfurizing biocatalysts. We have also proposed a model to construct competent desulfurizing recombinants involving use of CRISPR-Cas technology. The model can be used to over-express the dsz genes under a constitutive promoter in a suitable heterologous host, to get a steady expression of desulfurization pathway. This may serve as an inducement to develop better performing desulfurizing recombinant strains using CRISPR-Cas systems, which can be helpful in increasing the rate of biodesulfurization in future. [ABSTRACT FROM AUTHOR]

This study investigates the effects of various dosages of bacteria on the properties of sustainable bacteria blended fly ash (FA) concrete. Different series of concrete mixtures were designed, with Series C being the plain concrete mix (no FA and bacteria). Series CF contained FA concrete mixes that had 10%, 20% and 30% FA content. Series CB and CBF were prepared with bacteria with varying dosages. Surface deposition of calcium carbonate crystals was found to improve strength and decreased sorptivity by 30–60%, depending on the type of bacteria and FA proportion. The best results in comparison with normal and FA concrete for compressive strength (CS) were obtained to be 31.76 MPa. The bacteria solution to water ratio had a positive effect on strength and sorptivity property but with increasing ratio. This study also applies multiple regression analysisin estimating the CS of concrete that contains FA at a fixed value of bacterial dosage at different curing times. The present paper also shows a mathematical model to predict the CS of concrete with bacteria solution to water ratios. The X-ray diffraction and SEM analysis indicated the formation of calcite crystals in bacterial concrete specimens. [ABSTRACT FROM AUTHOR]

In recent years, with the continuous improvement of people's living standard, the importance of healthy lifestyles is becoming more and more recognized. Therefore, food safety has attracted much attention. This has prompted people to study new technologies that can guarantee food safety without the use of preservatives. Compared with other types of food preservatives, essential oils (EOs) are gotten more attention, because they meet the current development trend of food additives about "green", "safety" and "health". Therefore, this paper focuses on the research of effective contribution of EOs to inhibit the growth of foodborne pathogens, systematically summarized the commonly used EOs and their main extraction methods and chemical components and, the antibacterial mechanism of EOs on food borne pathogens, systematically analysis the specific application case of EOs in food discussed. Hoping to provide some reference and help to the relevant researchers. [ABSTRACT FROM AUTHOR]

There is a growing need in the construction industry to improve transfer and durability aspects of Portland pozzolana cement. Ureolytic bacteria have recently emerged as potential micro-organisms well known for precipitation of calcium carbonate through microbiologically induced calcite precipitation (MICP) process. MICP process has emerged as a viable mechanism for improvement of the PPC performance. This paper presents an in-depth discussion on the effects of Bacillus pseudofirmus, Bacillus sphaericus, Sporosarcina pasteurii, Bacillus cereus, Bacillus megaterium and Bacillus subtilis on some selected physico-mechanical properties of cement-based materials. These properties include standard consistency, setting time, compressive strength, water absorptivity, porosity and chloride ingress. The influence of pH, temperature and various bacteria nutrient requirements on optimum MICP process is also presented. In conclusion, benefits and drawbacks on the use of MICP has been discussed. MICP as a potential technique for improvement of physico-mechanical properties as well as repair of cracked cement-based structures has been discussed. [ABSTRACT FROM AUTHOR]

The article discusses various reports published within the issue, including one that deals with biologically controlled and induced mineralization with a special focus on magnetite and another on a study about mercury-bearing bacteria in association with clay minerals using transmission electron microscopy in a small-scale gold mine in Tanzania.

Immobilization technology is a method for restoring the ecological environment of oil-polluted areas. In this paper, the performance and degradation characteristics of immobilized microorganisms on different carriers were systematically studied starting with the selection of immobilized carriers. The results showed that cinnamon shell was the best carrier for screened Pseudomonas YT-11 to prepare immobilized microorganisms (diesel degradation rate was 69.57% in 5 days). On the basis of the determination of diesel degradability and SEM structure, the degradation mechanism of immobilized microspheres was concluded: diesel was adsorbed on the surface of microspheres and then entered the interior to be degraded by microorganisms. [ABSTRACT FROM AUTHOR]

There is potential for phages to prevent and control bacterial biofilms, but few studies have examined the effect of phages on the multispecies biofilms that characterize most bacterial infections. This paper reviews the mechanism of action of phages, the evidence supporting the view that phage therapy will be effective against bacterial targets and the opposite viewpoint, phage application approaches, and the comparative advantage of phage therapy in multispecies biofilms. The few reports measuring the actions of lytic phages against multispecies biofilms are also reviewed. The authors are cautiously optimistic about the application of phages against their targets when in multispecies biofilms because some lysis mechanisms do not require species specificity. [ABSTRACT FROM AUTHOR]

The weathering of wood through abiotic factors has been extensively studied. Much less research has been conducted on the influence of biotic factors on wood in exterior use that is not in ground contact, i.e. use class 3. There is especially a lack of research concerning the influence of the presence of bacterial and fungal communities on the weathering process of wood. The project aim is to identify any synergistic effects between biotic factors such as bacteria (Actinomycetes and Eubacteria) and fungi (Basidiomycota and Ascomycota) and abiotic factors such as light, temperature and moisture on the weathering of wood surfaces in use class 3. This paper presents results such as the amount of colony forming units (CFU), environmental scanning electron microscope analysis, colour changes and moisture content (MC) from preliminary experiments where wood surfaces were either naturally or artificially weathered. In order to study the interactions of fungi and bacteria on wood during the weathering process, the presence of microorganisms on natural weathered oak and Douglas fir surfaces had to be validated first. With the help of a surface contact test, microorganisms on the wood surfaces were transferred to agar plates and consequently incubated so that they could grow in appropriate conditions. Once the microbiological colonies had developed sufficiently, they were separated by selecting sections from the colonies and replated on fresh agar. A microcosm scale experiment, meaning the transfer of one specific bacteria and one fungi together in one petri dish, was carried out. This trial revealed that certain bacteria have an influence on the growth rate of certain fungi. In addition, an artificial weathering test was carried out in a QUV, which allows the degradation of samples using specific and known abiotic degrading parameters. The observation of the artificial weathered wood samples revealed that microorganisms are most definitely present in the QUV test apparatus and may influence the test results. [ABSTRACT FROM AUTHOR]

Calcareous cameral deposits have been described in several orthocerid and actinocerid nautiloids. According to the prevailing hypothesis, they were secreted during the lifetime of the animal, either by living tissues in the shell chambers, or by precipitation from the cameral liquid. In the present paper, cameral deposits are described in three species of Carboniferous orthocerid-like coleoid (Order Colorthocerida) from USA. The shell walls and septa in these coleoids are very thin and poorly calcified. In one half of the population of the three species, the septa are completely fragmented and there are no cameral deposits. In the other half of the population, the septa are partially fractioned and their surfaces are covered by well-developed cameral deposits. In contrast to the septa, the cameral deposits do not show any fractioning. To explain the origin of the cameral deposits, the following hypothetical scenario is the most realistic. After the death of the animals, the shells were accumulated on the sea floor and in one half of the population the septa became fully fractioned by the hydrostatic pressure. In shells of another half of the population, the septa were only partially fractioned. The calcifying bacteria entered the chambers of the dead shells through the porous connecting rings and gave rise to the cameral deposits. [ABSTRACT FROM AUTHOR]

The endemic, green-lipped mussel (Perna canaliculus), trademarked as Greenshell™ mussel, contributes most to the New Zealand aquaculture industry based on tonnage and export value. Research on mussel immunity is motivated greatly by economical and biosecurity necessities. Indeed, mussel aquaculture is threatened by pathogenic micro-organisms and environmental stressors. As such there is a need to understand the mechanisms that drive mussel immune responses and the associated interactions with the environment. Specifically, this review (1) analyses the existing immunological studies conducted on P. canaliculus, (2) evaluates the literature pertaining to mussel immunity at the cellular and humoral levels, (3) identifies and discusses pathogens that are relevant to P. canaliculus, (4) focuses on the virulent factors employed by mussel pathogens likely to induce diseases, (5) provides a comprehensive analysis of the response mechanisms employed by mussels to various stressors, and (6) explores omics applications and future perspectives in mussel immunology. Finally, this review highlights various strategies from immunological research, such as gene rearrangement, probiotics, immunostimulants, and selective breeding, promising to enhance mussel health and resilience in aquaculture. By exploring these immunological findings and their practical applications, this review contributes to sustainable mussel aquaculture, improving productivity and disease management in the industry. [ABSTRACT FROM AUTHOR]

The study aimed to analyse the potential of Lamiaceae essential oils, extracts, and hydrolats against bacterial biofilms. Bacterial cells Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus cereus were exposed to Thymus vulgaris L. (thyme), Salvia officinalis L. (sage), Mentha × piperita L. (mint) essential oils, extracts, and hydrolats. The result of the minimal inhibitory concentration assessment shows the highest antibacterial potential for essential oils, followed by extracts and hydrolats respectively. The anti-biofouling capacity revealed that thyme essential oil has the highest potential for biofilm prevention for all tested bacteria, reducing up to 91% of biofilm, followed by mint (88%) and sage (87%) essential oil. While the thyme extract (84%), sage extract (83%) and hydrolat (77%) we less effective. The chemical composition of thyme essential oil showed a high percentage of monoterpene hydrocarbons and oxygenated monoterpenes, among which p-cymene and thymol were the most predominant. The bacterial cell membrane integrity assessment shows a significant increase in dead cells by increasing the concentration of thyme essential oil. The findings of our research indicate that the choice of herbal preparation significantly affects the active components, thereby influencing both antibacterial and anti-biofouling capabilities. Lamiaceae essential oils show great potential for biofilm management and represent a good candidate for antibacterial application in pharmacy, medicine, and industry. [ABSTRACT FROM AUTHOR]

For the past few years, microbial biofilms have been emerging as a significant threat to the modern healthcare system, and their prevalence and antibiotic resistance threat gradually increase daily among the human population. The biofilm has a remarkable impact in the field of infectious diseases, in particular healthcare-associated infections related to indwelling devices such as catheters, implants, artificial heart valves, and prosthetic joints. Bacterial biofilm potentially adheres to any biotic or abiotic surfaces that give specific shelter to the microbial community, making them less susceptible to many antimicrobial agents and even resistant to the immune cells of animal hosts. Around thirty clinical research reports available in PUBMED have been considered to establish the occurrence of biofilm-forming bacteria showing resistance against several regular antibiotics prescribed against infection by clinicians among Indian patients. After the extensive literature review, our observation exhibits a high predominance of biofilm formation among bacteria such as Escherichia sp., Streptococcus sp., Staphylococcus sp., and Pseudomonas sp., those are the most common biofilm-producing antibiotic-resistant bacteria among Indian patients with urinary tract infections and/or catheter-related infections, respiratory tract infections, dental infections, skin infections, and implant-associated infections. This review demonstrates that biofilm-associated bacterial infections constantly elevate in several pathological conditions along with the enhancement of the multi-drug resistance phenomenon. [ABSTRACT FROM AUTHOR]

The experiment was conducted to investigate continuous hydrogen production with lower cost and sulphate-rich wastewater treatment. In this paper, both anaerobic bio-treatment of sulphate-rich wastewater and hydrogen production were applied to construct a laboratory-scale combined sulphur cycle based system. The system consisted of two reactors, which were a photocatalytic reactor and an anaerobic bioreactor, respectively. In the anaerobic bioreactor, sulphate-reducing bacteria (SRB) converted SO42- to S2-. The produced S2- yielded by SRB was further used as a sacrificial reagent to produce H2 in the photocatalytic reactor. Then, S2- was changed into SO42-, which returned to the anaerobic bioreactor for treatment again. The present study highlighted an advantage compared with the conventional method, in that no extra S2-was added to the photocatalytic reactor, which reduced the total cost and realized continuous hydrogen production. The average COD removal efficiency was 79.6%. [ABSTRACT FROM AUTHOR]

This paper focuses on a hand-washing campaign conducted at a mid-sized university in the western USA. Using the theoretical framework of the extended parallel process model (EPPM), formative, focus group research nuts conducted. It was determined that common threats used in hand-washing campaigns such as spreading germs and getting sick were not relevant to the students in the target audience, did not have high susceptibility, nor high response efficacy. Rather, the students indicated the grossness of urine and faeces on the hands was the most relevant threat that would yield the highest behaviour change and so campaign messages focusing on the 'gross' factor were created and placed in the randomly selected experimental dorms. Behavioural observations were conducted immediately before and after the campaign. A post-campaign online survey was completed by 518 dorm residents. Results indicate that using EPPM to create health communication messages yields positive behaviour change when formative research is conducted to determine not only self and response efficacy for the behaviour, and susceptibility and severity for the threat, but more importantly, to also determine the most relevant threat for the target audience. Results also appear to support an integrated communication approach to campaign success, as discussion about campaign messages with friends yielded increased variance in hand washing among these students. A version of this paper was presented at the Kentucky Conference on Health Communication, 17--19th April, 2008. [ABSTRACT FROM AUTHOR]

This paper examines similarities and differences in media discourses relating to methicillin resistant Staphylococcus aureus (MRSA) at three important points in the development of the bacterium and its perception by the public over the last decade. We analyse three increasingly large sets of texts from the national media using a variety of complementary qualitative and quantitative methods. As such this paper exploits, develops and empirically assesses an emerging methodological trend in applied linguistics, namely the convergence of critical metaphor analysis, with corpus linguistics and science and technology studies. Using this, the study identifies a shifting media narrative that involves changes in dramatis personae over the decade. First, personified forces of nature, doctors and hospitals are engaged in a battle of evil against good, but also intelligence over stupidity. Second, we are presented with victims of personified bacterial forces and doctors and hospitals cast as perpetrators of crimes of omission by not cleaning hands or wards. Third, the malignant forces of politics try to exploit the evil forces of nature for their own ends while a mediator between the doctors and the potential victims of MRSA emerges and is given political and symbolic power: the modern matron. [ABSTRACT FROM AUTHOR]

In this paper, we consider a class of coupled cooperative reaction-diffusion systems, in which onepopulation (or subpopulation) diffuses while the other is sedentary. We use the shooting method to prove the existence of the bistable travelling wave, and then obtain its global attractivity with phase shift and uniqueness (up to translation) via the dynamical system approach. The results are applied to some specific examples of reaction-diffusion population models. [ABSTRACT FROM AUTHOR]

Standard experimental protocols for biodegrading petroleum hydrocarbons employ microbiological and/or analytical analysis, and require advanced machines and specialized professionals to carry them out. Furthermore, the obtained results involve a high margin of error. In this paper, a new experimental technique was developed to facilitate the study of microbial capability to degrade petroleum oily sludges. The technique is based on growing microorganisms on 0.22 μm filter membranes laid over oily sludge placed in metallic cups. The microbial growth was assessed using the plate counts technique. Sludge degradation was assessed using Fourier Transform Infrared Spectrometry (FTIR), and compared to the decrease in total petroleum hydrocarbons (TPH) using solvent extraction. The protocol was tested using three types of inocula: fungal inoculum containing Paecilomyces variotii; bacterial inoculum containing Bacillus cereus; and fungal-bacterial inoculum containing both strains. Both, fungal and bacterial, strains were isolated from the oily sludge used in the present study, and were tentatively identified as oil degraders. The results of the newly developed technique helped to assess the potential of these cultures to tolerate and grow on the oily sludge. [ABSTRACT FROM AUTHOR]

It is now almost 50 years since the gregarious settlement of barnacles and its chemical basis was first described. Although originally noted for Elminius modestus, mechanistic studies of gregariousness have focused on two species, Semibalanus balanoides and Balanus amphitrite. By virtue of its ease of study and its economic importance as a fouling organism, the latter species has assumed increasing importance in recent years. This paper will provide an overview of studies on settlement pheromones and their perception. An adult glycoprotein, arthropodin (now known as settlement‐inducing protein complex or SIPC), was once thought to be the sole pheromone involved in the induction of cypris larval settlement. At least two other pheromones are now known to be involved, a waterborne cue originating from the adult and the cypris temporary adhesive. The latter is related, immunologically, to SIPC. In keeping with many other examples of chemical communication, the available evidence suggests that barnacle settlement induction involves receptor‐ligand interactions and a signal transduction pathway(s) that translates into attachment and metamorphosis. Similar findings have been reported for some, but not all, marine invertebrate larvae examined thus far and the implications for antifoulant development are discussed. [ABSTRACT FROM PUBLISHER]

Biocementation is a recently developed new branch in geotechnical engineering that deals with the application of microbiological activity to improve the engineering properties of soils. One of the most commonly adopted processes to achieve soil biocementation is through microbially induced calcite precipitation (MICP). This technique utilizes the metabolic pathways of bacteria to form calcite (CaCO3) that binds the soil particles together, leading to increased soil strength and stiffness. This paper presents a review of the use of MICP for soil improvement and discusses the treatment process including the primary components involved and major affecting factors. Envisioned applications, potential advantages and limitations of MICP for soil improvement are also presented and discussed. Finally, the primary challenges that lay ahead for the future research (i.e. treatment optimization, upscaling for in situ implementation and self-healing of biotreated soils) are briefly discussed. [ABSTRACT FROM PUBLISHER]

Probiotic bacteria are being increasingly added to food for developing products with health-promoting properties. However, the efficacy of probiotics in commercial products is often questioned due to the loss of their viability during shelf storage and in human gastrointestinal tracts. Encapsulation of probiotics has been expected to provide protection to probiotics, but not many commercial products contain encapsulated and viable probiotic cells owing to various reasons. To promote the development and application of encapsulation technologies, this paper has critically reviewed previous publications with a focus on the areas where studies have fallen short, including insufficient consideration of structural effects of encapsulating material, general defects in encapsulating methods and issues in evaluation methodologies and risk assessments for application. Corresponding key issues that require further studies are highlighted. Some emerging trends in the field, such as current treads in encapsulating material and recently advanced encapsulation techniques, have also been discussed. [ABSTRACT FROM AUTHOR]

Prompted by the exigencies of the First World War, the ability of certain bacteria to produce a mixture of organic solvents from carbohydrates was successfully harnessed as a source of acetone for use in the manufacture of cordite. From pilot plant studies conducted in an East London distillery, it was rapidly developed into what is now recognised as the first modern industrial fermentation process. In the post-war period, the process continued to thrive, especially in North America, as another of its products, butanol, became important in the burgeoning automobile industry. This paper describes the background to the development of acetone–butanol fermentation as an industrial process, its growth during the war years and how it contributed to the development of today’s biotechnology industry producing pharmaceuticals, food additives and many other microbial products. [ABSTRACT FROM AUTHOR]

The permutation flow-shop scheduling problem (PFSP) is a typical combinational and non-deterministic polynomial-hard problem, with discrete solution space. In this paper, a novel bacterial foraging optimisation algorithm (BFO) has been proposed to solve the PFSP. Difficulties such as slow convergent speeds and entrapment in the local optimum were incurred by the original BFO algorithm in solving a high-dimensional combinatorial optimisation problem. In order to deal with these difficulties, a differential evolution operator and a chaotic search operator were each introduced into the original BFO algorithm to enhance the activity levels of the individual bacterium and to extend the local searching space. Theoretical analysis showed that the improved algorithm obtained more motility in chemotaxis and could converge to the global optimum with a probability of 1. Simulation results and comparisons to both continuous and combinatorial benchmark problems were used to demonstrate the effectiveness of this novel optimisation algorithm. [ABSTRACT FROM AUTHOR]

Oligosaccharides have been marketed since the 80s as low-calorie agents and recently have gained interest in the pharmaceutical and food industry as functional sweeteners and prebiotic enriching population of Bifidobacteria. Currently, they have an approximated value of $200 per kg and recently, inulin has been proposed as a feedstock for production of oligosaccharides through selective hydrolysis by action of endoinulinase. High optimum temperature (60°C) and thermostability are two important criteria that determine suitability of this enzyme for industrial applications as well as enzyme cost, a major limiting factor. Significant reduction in cost can be achieved by employing low-value and abundant inulin-rich plants as Jerusalem artichoke, dahlia, yacon, garlic, and onion, among others. In general, the early harvested tubers of these plants contain a greater amount of highly polymerized sugar fractions, which offer more industrial value than late-harvested tubers or those after storage. Also, development of recombinant microorganisms could be useful to reduce the cost of enzyme technology for large-scale production of oligosaccharides. In the case of fungal inulinases, several studies of cloning and modification have been made to achieve greater efficiency. The present paper reviews inulin from vegetable sources as feedstock for oligosaccharides production through the action of inulinases, the impact of polymerization degree of inulin and its availability, and some strategies to increase oligosaccharide production. [ABSTRACT FROM AUTHOR]

The use of algicidal bacteria has gained prominence as natural solution to control the worrying increase of harmful algal blooms worldwide. However, although cyanobacterial blooms (cyanoHABs) often dominate freshwater bodies, recent reviews on the subject have addressed cyanobacteria in the second place and focused more on bacteria-algae interactions. This article provides a critical review of the fundamental aspects of searching for, isolating and assaying candidate algicidal bacteria targeting cyanobacteria. Possible species-specific interactions and the different modes of action of bacteria against different species of cyanobacteria are also discussed. It has been observed that there is a clear bias in the literature toward the genus Microcystis, being by far the most studied and reviewed to date. This contrasts with the numerous studies showing cyanobacterial blooms dominated by other harmful species, such as the genera Planktothrix, Aphanizomenon or Raphidiopsis. To add new knowledge to the lack of current studies on these genera, a separate experimental section has been included in this review with research results on the sensitivity of nine harmful freshwater cyanobacteria and two green algae to different bacteria and algicidal compounds. Finally, certain ecological and biosafety risks that must be taken into account when applying algicidal bacteria as a bioaugmentation strategy are also highlighted. Overall, this review is presented as an attempt to outline the knowledge gathered over the last thirty years of research, while raising new questions and debates on key issues that remain poorly understood. [ABSTRACT FROM AUTHOR]

Soil samples were collected from research farm of Ebonyi State University and mining site in Izzi Local Government Area (L.G.A) of Ebonyi State. Rhizobacteria from rhizosphere of maize were identified using molecular methods. Tolerance of the isolates to heavy metals was assessed using standard laboratory techniques. The heavy metal profile of the soil was determined using atomic absorption spectrophotometer (AAS). Ability of the PGPB to remediate heavy metal polluted soil was assessed with hot plate aqua-regiae digestion method. The isolates were identified as: Pseudomonas fluorescens strain 5113, Alcaligenes faecalis strain P156, Pseudomonas syringae HS191, Bacillus subtilis strain NBSL51 and Bacillus cereus strain 20 UPMNR. P. fluorescens exhibited maximum tolerance at different concentrations of metals while A. faecalis had minimum tolerance. The heavy metal profile of the soil was determined and expressed in ppm as lead (25.0), copper (2.4), chromium (1.2) and zinc (16.0). The Isolates remediated the heavy metals. P. fluorescens + B. cereus maximally degraded the metals with values of (Pb = 87.2%, Zn = 69.25%, Cr =67.5%) while B. cereus alone degraded 70.0% Cu. P. fluorescens + B. cereus is recommended for soil that is contaminated with chromium, lead and zinc while B. cereus is recommended for copper contaminated soils. [ABSTRACT FROM AUTHOR]

This study aims to characterize and determine the antibacterial activities of synthesized Strobilanthes crispus-mediated AgNPs (SC-AgNPs) against Streptococcus mutans, Escherichia coli and Pseudomonas aeruginosa. S. crispus water extract acts as a reducing and capping agent in the synthesis of AgNPs. The synthesized AgNPs were characterized by using UV-Vis spectrophotometer, dynamic light scattering (DLS), field emission scanning electron microscope (FESEM), X-ray diffractometer (XRD) and Fourier transform infra-red (FTIR). FESEM images showed a rough surface with a spherical shape. The average size distribution of 75.25 nm with a polydispersity index (PDI) of 0.373. XRD analysis matched the facecentred cubic structure of silver. FTIR analysis revealed a shifted peak from 1404.99 to 1345.00 cm-1. MIC and MBC values of SC-AgNPs were 1.25 mg/mL and 2.5 mg/mL against E. coli, P. aeruginosa and S. mutans, respectively. Time-kill assay showed that SC-AgNPs significantly reduced bacterial growth as compared to non-treated bacteria. Morphologies of bacteria treated with SC-AgNPs were shrunk, lysed, irregular and smaller as compared to control. SC-AgNPs significantly disrupted the gene expression of eae A, gtf B and Pel A (p<0.05). This study indicated that the synthesized SC-AgNPs were stable with enhanced antibacterial activities. [ABSTRACT FROM AUTHOR]

During the production and processing of coal, burning it for energy production may cause a series of environmental pollution due to the amount of sulphur in it. When the consumed sulphur in coal is in the form of sulphur dioxide at the end of combustion, it reacts with water at high altitudes. Moreover, it goes down to the earth in the form of sulphuric acid, as well as damaging plants. The corrosive harmful impact on industrial plants is the removal of the sulphur in the coal when it is environmental. Microorganisms that use sulphur as food to eliminate the anxiety of clean production brought about by the chemical method. This review determined the study contains information about which microorganism is effective in removing sulphur in coal and also the types of organisms that should be according to the organic sulphur type in coal. [ABSTRACT FROM AUTHOR]

Food safety is a global health concern. For the prevention and recognition of problems related to health and safety, detection of foodborne pathogen is of utmost importance at all levels of food production chain. For several decades, a lot of research has been targeted at the development of rapid methodology as reducing the time needed to complete pathogen detection tests has been the primary goal of food microbiologists. With the result, food microbiology laboratories now have a wide array of detection methods and automated technologies such as enzyme immunoassay, polymerase chain reaction, and microarrays, which can cut test times considerably. Nucleic acid amplification strategies and advances in amplicon detection methodologies have been the key factors in the progress of molecular microbiology. A comprehensive literature survey has been carried out to give an overview in the field of foodborne pathogen detection. In this paper, we describe the conventional methods, as well as recent developments in food pathogen detection, identification, and quantification, with a major emphasis on molecular detection methods. [ABSTRACT FROM AUTHOR]