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This paper aims to study five vegetables extracts as possible additives to control bacterial growth on indoor waterborne paints. The extracts were obtained from the weeds Raphanus sativus, Rapistrum rugosum, Sinapis arvensis, Nicotiana longiflora and Dipsacus fullonum, used in traditional medicine as antimicrobial compounds.

Weeds extracts were characterized by Fourier transform infrared spectroscopy and UV–Vis spectrophotometry. Their antibacterial activity against Escherichia coli and Staphylococcus aureus was also determined. Afterward, selected extracts were incorporated in waterborne paint formulations. The paints’ antimicrobial activity was assessed against S. aureus, monitoring biofilm formation by environmental scanning electron microscopy.

As a general rule, results showed that tested paints were efficient in inhibiting biofilm formation, especially that formulated with Nicotiana longiflora.

The tested paints can be used to protect walls from microbial colonization, which shortened coatings’ useful life by discoloration and/or degradation. Concomitantly, indoor microbial colonization by aerosols could be also diminished. This is especially important in places that should have high standards of environmental hygiene, as in the food industry, health-care and sanitary centers.

The main value of this research was to study the antimicrobial activity of weeds extracts and to incorporate them in waterborne paints to diminish bacterial biofilm formation. This biofilm discolors and degrades the paint, and causes health problems. The use of natural compounds in coatings is increasing because of the convenience of using renewable sources, such as natural antimicrobials, in paint formulations.

This research examines the association of physical development density, prevalence and types of microbes in colonized façade finishes of buildings in Enugu metropolis, Nigeria.

Survey and experimental research designs were adopted. A total of 383 buildings were investigated with samples collected from those with colonized façade finishes. The microbes were identified using the standard procedure for genomic sequencing with descriptive statistics, and the chi-square test used to analyse the data.

The results revealed a 64% prevalence of microbial colonization and a significant association between this and physical development density with 71.0% of the colonized buildings located in high-density neighbourhoods of the metropolis. The sequencing also showed 24 different microbes with Trichophyton tonsurans, Trichophyton mentagrophytes and Trichoderma harzianum species being the most common in the colonized façade finishes.

The research informs building professionals and owners of the specific microbes involved in the colonization of façade finishes of buildings in high-density urban areas. It also provides a clue about the nature of damages and defects associated with microbial colonization of building façades and the type of biocide additives required for the production of microbial-resistant façade finishes in the hot-humid tropical environment of Nigeria and beyond.

The study has shown that there is a significant relationship between the intensity of urban land use and microbial colonization of façade finishes of buildings. It also identified some new or less known microbes responsible for the biodeterioration of façade finishes and the effects this has on the buildings and public health in the hot-humid tropics of Enugu, Southeast Nigeria.

Buildings respond differently to microbial invasion depending on the design, type of construction materials and finishes used and extent of exposure to climatic factors. However, in the hot-humid tropical environment of Nigeria, much is not known about how buildings with different types of façade finishes or claddings are liable to microbial decay. The purpose of this research is to investigate the susceptibility of buildings with different types of façade finishes to microbial decay in Enugu metropolis, southeast Nigeria.

A survey involving physical observation of purposively selected 383 buildings and questionnaire administration to their owners was carried out in the study area. The data were subjected to descriptive and logistic regression analyses.

Most of the 383 buildings sampled were less than 41 year and 47% of them had painted façade finishes followed by 25.1% with cementitious finishes. Around 63.4% of the buildings had their façade finishes or claddings colonised by microbes. Older buildings of 15 years and above and those with cementitious materials and paints as their predominant façade finishes were more likely to experience microbial decay than newer ones and those having refractory bricks, ceramic tiles, aluminium composite materials and plastics/polymers as their predominant façade finishes or claddings.

The study identifies the categories of buildings that are likely to be more susceptible to microbial decay; and thus contributes to research on how to slow down the rate of biodeterioration of building façade finishes or claddings in the hot-humid tropical environments.

This is the first study on the susceptibility of buildings with different types of façade finishes or claddings to microbial decay in the hot-humid tropical environment of Enugu metropolis, southeast Nigeria. It also provides a clue on the age at which buildings become more vulnerable to microbial decay in the study area.

Some of the mechanisms involved in the microbial colonisation and biodeterioration of metalworking fluids are described in an attempt to design a more realistic and meaningful laboratory assay procedure. The history of bioassay techniques is reviewed and the nature and composition of metalworking fluids is examined. Maximisation of the performance of biocides against micro‐organisms and the influence of tramp oil contamination is assessed.

This article seeks to review the incidence of food allergy or food sensitization in children which has increased during the past decade and can manifest urticaria or angioedema, anaphylaxis, atopic dermatitis, respiratory symptoms or gastro‐intestinal disorders, and to looks closely at probiotic therapy, which appears to alleviate allergy inflammation.

Literature related to probiotics and their exploitation as probiotic therapy for gastro‐intestinal allergenic infants has been primarily composed from two databases, namely, Dairy Science Abstracts and Entez Pub Med.

Development of intestinal microbiota is considered to be a consequential factor affecting the health of newborns and could be achieved by nutritional change in diet or by consumption of probiotic through fermented milks. Animal and human trials revealed that probiotics can affect host‐resistance to intestinal infection as well as various immune functions and alleviate intestinal inflammation, normalize gut mucosal dysfunction and down‐regulate hypersensitivity reaction. Mode of action of probiotics is mediated by the microbial composition as well as metabolic activity of the intestinal flora. Beneficial properties of probiotics suggest their application for probiotic therapy of food‐allergenic infants.

Ingestion of fermented milk products containing probiotic cultures may provide health benefits in terms of colonization and normalization of intestinal flora, thereby alleviating food allergenicity in infants.

The purpose of this study is to apply silver nanoparticles on the cellulosic fabric via a green cross-linking approach to obtain antibacterial textiles. The cellulosic fabrics may provide an ideal enclave for microbial growth due to their biodegradable nature and retention of certain nutrients and moisture usually required for microbial colonization. The application of antibacterial finish on the textile surfaces is usually done via synthetic cross-linkers, which, however, may cause toxic effects and halt the biodegradation process.

Herein, we incorporated citrate moieties on the cellulosic fabric as eco-friendly crosslinkers for the durable and effective application of nanosilver finish. The nanosilver finish was then applied on the citrate-treated cellulosic fabric under the pad-dry-cure method and characterized the specimens for physicochemical, textile and antibacterial properties.

The results expressed that the as-prepared silver particles possessed spherical morphology with their average size in the nano range and zeta potential being −40 ± 5 mV. The results of advanced analytical characterization demonstrated the successful application of nanosilver on the cellulosic surface with appropriate dispersibility.

The nanosilver-treated fabric exhibited appropriate textile and comfort and durable broad-spectrum antibacterial activity.

The treated cellulosic fabric expressed that the cross-linking, crystalline behavior, surface chemistry, roughness and amphiphilicity could affect some of its comfort and textile properties yet be in the acceptable range for potential applications in medical textiles and environmental sectors.

Bacterial exopolysaccharides (eps) have fascinating chemical compositions, properties and structures which could be used in the modification of natural fibres. Bacterial eps have therefore been used to modify plant cellulose fibre surface and impart desired properties. The purpose of this paper is therefore to investigate the influence of gin trash cultured bacteria eps on the physical and structural properties of cotton fibres.

Gin trash soil sample was collected from a ginnery in Kenya, and physiochemical and microbial characterization was done. The soil sample was then fermented for 24 h before being used to treat raw cotton fibres at varied conditions of temperature, pH and treatment time periods. Physical and structural properties of the treated fibres were then determined using USTER HVI-1000 M700, Fourier transform infrared, scanning electron microscope (SEM) and X-ray diffraction (XRD) and compared with those of the raw fibres.

The bacteria broth treated fibres were found to have increased in strength, spinning consistency index, elongation and fineness by 25.44, 24.30, 11.70 and 3.60%, respectively. The variations were attributed to interactions of bacterial eps with cotton cellulose through hydrogen bonding. SEM and XRD analysis revealed an increase in fibre surface roughness and crystallinity, respectively.

Bacterial eps have been used to modify plant cellulose fibre surface and impart desired properties. Eps producing bacteria have been isolated from different habitats such as saline water, soil samples, food wastes and petroleum-contaminated soil. To the best of the authors’ knowledge, bacterial eps cultured from gin trash soil sample for modification of cotton fibres have however not been previously done, hence the originality of the current study.

Colonies of Actynomyces israelii bacteria have been found in removed copper intra‐uterine devices (IUD) used as a long‐term contraceptive method. The purpose of this paper is to characterize the biofilm developed under anaerobic conditions by Actynomyces israelii on IUD surface, and its influence in the copper corrosion processes.

The dissolution of copper on the intra‐uterine cavity prevents conception because of the toxic effect of the ions released. Nevertheless, microbiological growths have been detected on the IUD devices retired after long periods of insertion. In order to know about the influence of the biofilm on the corrosion of copper, electrochemical, spectroscopic and surface analysis techniques were applied to study the phenomenon.

A porous Actynomyces israelii biofilm was formed on the copper IUD surface. The bacteria colony had developed in an exopolimeric substrate, which protects it from the toxic effect of copper ions. The corrosion process was not inhibited by the biofilm, due to the pores present which permit the transport of species through them.

The results of this study show that there is no decay in the contraceptive function of the IUDs due to the presence of a bacterial biofilm on its surface.

The relationship between microbial colonization and the corrosion process of copper IUD under anaerobic conditions was characterized. These results will complement previous investigations performed on the study of corrosion of copper IUDs under different conditions.

The purpose of this paper is to study the metal-Microbe interaction playing a crucial role in microbiologically influenced corrosion (MIC) and biofouling of materials in cooling water systems. Treatment regimens should be planned based on this understanding.

Attempts were made in the past decades to characterize and understand biofilm formation on important power plant structural materials such as carbon steel (CS), stainless steel (SS) and titanium in fresh water and in seawater to achieve better control of biofouling and minimize MIC problems.

This report presents the results of detailed studies on tuberculation-formed CS because of the action of iron-oxidizing bacteria and the effects of algae- and bacteria-dominated biofilms on the passivity of SS. The preferential adhesion of different bacterial species on SS under the influence of inclusions and sensitization was studied in the context of preferential corrosion of SS weldments due to microbial action. Detailed characterization of biofilms formed on titanium (the likely condenser material for fast breeder reactors) after exposure for two years in Kalpakkam coastal waters revealed intense biofouling and biomineralization of manganese even in chlorinated seawater. Studies on the effectiveness of conventional fouling control strategies were also evaluated.

The detailed studies of different metal/biofilm/microbe interactions demonstrated the physiological diversity of microbes in the biofilms that were formed on different materials, coupling their cooperative metabolic activities with consequent corrosion behaviour. These interactions could enhance either anodic or cathodic reactions and exploit metallurgical features that enhance biofilm formation and/or the capacity of microbes to mutate and overcome mitigation measures.

Antimicrobials may be incorporated into garments to protect the textiles, control malodour or to potentially reduce the spread of infection. Yet still not well understood is how antimicrobial-treated textiles may influence a person's resident microflora during wear, as limited in vivo testing has previously been carried out. The purpose of this paper is to assess whether normal skin microflora was altered as a result of contact with selected antimicrobial-treated fabrics.

Three selected antimicrobial-treated fabrics (i.e. Fabric 1: triclosan; Fabric 2: zinc pyrithione derivative; and Fabric 3: silver chloride and titanium dioxide) were placed on the forearm of participants (n=19). Bacterial counts obtained under treated and untreated fabrics following 24 hours of occlusion were compared. The antimicrobial efficacy of fabrics displayed in vitro was also compared with the activity displayed in vivo.

Two of the three fabrics (Fabrics 1 and 2) reduced bacterial populations on the skin following 24 hours occlusion compared to the matched control fabrics (Fabric 1: p<0.05; Fabric 2: p<0.001). Whereas, following occlusion with Fabric 3 bacterial populations were not significantly different than the matched control. The present study demonstrated that in vitro assessment of antimicrobial capacities of fabrics do not necessarily predict the effects of such fabrics during wear.

The paper highlights that in vivo studies are a necessary and important tool for understanding the interactions of an antimicrobial-treated fabric with the wearer's skin. As well, the new method developed can be used by other researchers to examine the potential impact on skin microflora due to contact with antimicrobial-treated textiles.