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Aims: This study was designed to analyse the prevalence of class 1 and class 2 integron integrase genes among antibiotic-resistant coliform bacteria isolated from paper currency circulating in Pakistan., Methods and Results: A total of 500 individual currency notes were collected from different food vending sites at Lahore, Pakistan. Bacterial population were identified by biochemical and PCR techniques. Antimicrobial susceptibility testing was performed by disc diffusion assay. The highest bacterial population on currency was found from street vendors and butcher shops. Escherichia coli was found to be the most prevalent coliform bacteria followed by Klebsiella sp. and Enterobacter sp. PCR amplification of antimicrobial resistance gene showed the presence of ampC, bla TEM , bla NDM-1 , qnrA, tet(A) and tet(B) genes among coliform isolates. A total of 47 integron integrase bearing strains of coliform bacteria were analysed. Sequence analysis showed the presence of dfrA1-aadA1, dfrA1, dfrA5, dfrA7, aadA1, aadA4 cassette arrays in class 1 integron and dfrA1-sat2-aadA1 in class 2 integrase genes., Conclusion: Circulating currency was heavily contaminated with antimicrobial-resistant coliform bacteria bearing class 1 and class 2 integron integrase genes., Significance and Impact of the Study: This study describes a potential threat of severe bacterial infections due to improper hand hygiene and community sanitation when dealing with the currency notes., (© 2020 The Society for Applied Microbiology.)

Aims: The utilization of micro-organisms in pulp and paper industries has proved biobleaching technology as an environmentally friendly alternative to the conventional approach. In this paper, the effect of actinobacterial fermentation broth on pulp biobleaching has been investigated., Methods and Results: Actinobacterial colonies were isolated from lignocellulose-rich soil samples and screened for xylanase production and bleaching activity. The most efficient isolate in bleaching activity showed 100% similarity to Streptomyces rutgersensis. Pulp treatment with 5-day fermentation broth of this strain showed up to 7% increase in brightness (30°C for 6 h, pH (5-7)) compared to untreated (control) pulp. Also, after 60 min biotreatment, significant reduction (12·5%) in consumption of bleaching chemicals was achieved to obtain final brightness of 55%., Conclusion: Actinobacterial fermentation broth can be considered as a rich source of effective biobleaching agents which may be considered as environmental friendly and cost-effective technique in comparison with traditional method., Significance and Impact of the Study: Our findings showed ability of S. rutgersensis UTMC 2445 in bleaching chemomechanical paper pulp. Also, two strains of Saccharothrix, a rare actinobacterium, with biobleaching activity were introduced. In the proposed method, there is no need to use purified enzymes, and biobleaching process can be done using the fermentation broth., (© 2019 The Society for Applied Microbiology.)

Aims: To evaluate whether decoloured cell-free supernatant of Lysobacter enzymogenes C3 can decrease paper bioreceptivity to fungal attack., Methods and Results: To prepare colourless C3 supernatant, single-factor design and uniform design were applied. The optimum conditions with high decolouration degree and low antifungal activity loss were achieved as follows: carbon granule content 1·6% (M/V), temperature 27°C, decolouring time 1·2 h and pH 8·0. An agar plate bioassay was used to assess the antifungal activity of the decoloured supernatant against the fungal isolates obtained from contaminated books, and strong suppression was observed. Small-sacle laboratory test was further introduced, in which common book papers were artificially inoculated with the fungal isolates, and then sprayed uniformly with decoloured supernatant or water. The results showed that, after treatment, the paper showed a significantly low extent of fungal colonization and high tensile strength, and maintained the same colour before and after treatment., Conclusion: These results suggest that the decoloured C3 supernatant inhibits fungal growth on types of paper commonly used in books., Significance and Impact of the Study: Decoloured C3 supernatant could be used as a preventive agent to protect books and other paper-based items against fungal growth., (© 2019 The Society for Applied Microbiology.)

Summary: Numerous studies are published on the benefits of electric hand dryers vs paper towels (PT) for drying hands after washing. Data are conflicting and lacking key variables needed to assess infection risks. We provide a rapid scoping review on hand‐drying methods relative to hygiene and health risks. Controlled vocabulary terms and keywords were used to search PubMed (1946–2018) and Embase (1947–2018). Multiple researchers independently screened abstracts for relevance using predetermined criteria and created a quality assessment scoring system for relative study comparisons. Of 293 papers, 23 were included in the final analysis. Five studies did not compare multiple methods; however, 2 generally favoured electric dryers (ED); 7 preferred PT; and 9 had mixed or statistically insignificant results (among these, 3 contained scenarios favourable to ED, 4 had results supporting PT, and the remaining studies had broadly conflicting results). Results were mixed among and within studies and many lacked consistent design or statistical analysis. The breadth of data does not favour one method as being more hygienic. However, some authors extended generalizable recommendations without sufficient scientific evidence. The use of tools in quantitative microbial risk assessment is suggested to evaluate health exposure potentials and risks relative to hand‐drying methods. We found no data to support any human health claims associated with hand‐drying methods. Inconclusive and conflicting results represent data gaps preventing the advancement of hand‐drying policy or practice recommendations. [ABSTRACT FROM AUTHOR]

Aims: The concept of using specific dietary components to selectively modulate the gut microbiota to confer a health benefit, defined as prebiotics, originated in 1995. In 2018, a group of scientists met at the International Scientific Association for Probiotics and Prebiotics annual meeting in Singapore to discuss advances in the prebiotic field, focussing on issues affecting functionality, research methodology and geographical differences. Methods and Results: The discussion ranged from examining scientific literature supporting the efficacy of established prebiotics, to the prospects for establishing health benefits associated with novel compounds, isolated from different sources. Conclusions: While many promising candidate prebiotics from across the globe have been highlighted in preliminary research, there are a limited number with both demonstrated mechanism of action and defined health benefits as required to meet the prebiotic definition. Prebiotics are part of a food industry with increasing market sales, yet there are great disparities in regulations in different countries. Identification and commercialization of new prebiotics with unique health benefits means that regulation must improve and remain up‐to‐date so as not to risk stifling research with potential health benefits for humans and other animals. Significance and Impact of Study: This summary of the workshop discussions indicates potential avenues for expanding the range of prebiotic substrates, delivery methods to enhance health benefits for the end consumer and guidance to better elucidate their activities in human studies. [ABSTRACT FROM AUTHOR]

Aim: The aim of the study was to purify and characterize cellulase from a previously isolated Novosphingobium sp. strain Cm1 and to evaluate its waste hydrolysis and bio‐stoning efficiency. Materials and Methods: There is a growing demand for cellulase, a multipurpose enzyme widely used in industrial applications. Here, we purified cellulase from Novosphingobium sp. Cm1 by cellulose chromatography. SDS‐PAGE revealed a molecular mass of 25 kDa. After 18‐fold purification, the cellulase had an activity of 31.4 U/mg at pH of 5 and 40°C, and it retained activity at a wide range of pH and temperatures. The presence of Fe2+ and Co2+ boosted the enzyme activity by 57% and 25% respectively. The hydrolysing capacity of the strain towards cellulosic material was assessed for two paper types and the highest activity (2.6 ± 0.05 U/ml) was found with filter paper as the sole carbon source. Alterations in the structure of the papers as a result of bacterial hydrolysis were confirmed by scanning electron microscope and Fourier‐transform infrared spectroscopy. The strain was also tested for its potential in various industrial applications and exhibited pectinolytic activity (6.78 ± 0.68 U/ml), xylanolytic activity (0.22 ± 0.14 U/ml) and bio‐stoning ability. Conclusion: The highly active purified cellulase has a broad pH and temperature range. The strain possesses waste‐hydrolysing ability, pectinolytic and xylanolytic ability along with bio‐stoning capacity. Significance and Impact of the Study: The efficacy and versatility of the enzyme from Novosphingobium sp. Cm1 make it an excellent candidate for diverse industrial applications. [ABSTRACT FROM AUTHOR]

Aim: The purpose of this work was to study the feasibility of producing economic flame retardant bacterial cellulose (BC) and evaluating its behaviour in paper production., Methods and Results: This type of BC was prepared by Gluconacetobacter subsp. xylinus and substituting the glucose in the cultivation medium by glucose phosphate as a carbon source; as well as using corn steep liquor as a nitrogen source. The investigated processing technique did not dispose any toxic chemicals that pollute the surroundings or cause unacceptable effluents, making the process environmentally safe. The fire retardant behaviour of the investigated BC has been studied by non-isothermal thermogravimetric analysis (TGA & DTGA). The activation energy of each degradation stage and the order of degradation were estimated using the Coats-Redfern equation and the least square method. Strength, optical properties, and thermogravimetric analysis of BC-phosphate added paper sheets were also tested., Conclusions: The study confirmed that the use of glucose phosphate along with glucose was significant in the high yield production of phosphate containing bacterial cellulose (PCBC1); more so than the use of glucose phosphate alone (PCBC2). Incorporating 5% of the PCBC with wood pulp during paper sheet formation was found to significantly improve kaolin retention, strength, and fire resistance properties as compared to paper sheets produced from incorporating bacterial cellulose (BC)., Significance and Impact of the Study: This modified BC is a valuable product for the preparation of specialized paper, in addition to its function as a fillers aid.

Aims: To isolate aerobic mesophilic bacilli and thermophilic bacteria from different paper mill samples and to evaluate their potential harmfulness., Methods and Results: A total of 109 mesophilic and 68 thermophilic isolates were purified and characterized by automated ribotyping and partial 16S rDNA sequencing. The mesophilic isolates belonged to the genera Bacillus (13 taxa), Brevibacillus (three taxa) and Paenibacillus (five taxa). The thermophilic bacteria represented seven taxa of Bacillus, Geobacillus or Paenibacillus, four of proteobacteria and one of actinobacteria. The most frequently occurring bacteria were Bacillus cereus, B. licheniformis, Pseudoxanthomonas taiwanensis and bacteria closely related to Paenibacillus stellifer, P. turicensis or Leptothrix sp. One mill was contaminated throughout with bacteria of a novel mesophilic genus most closely related to Brevibacillus centrosporus and another with bacteria of a novel thermophilic genus most closely related to Hydrogenophilus thermoluteolus. One B. cereus isolate producing haemolytic diarrhoeal enterotoxin was detected and all the tested B. licheniformis isolates produced a metabolite toxic to boar sperm cells., Conclusions: The bacilli and thermophilic bacteria isolated represent species which should not present occupational hazards in paper mill environments. The most harmful bacterium detected was B. licheniformis and potentially also B. cereus., Significance and Impact of the Study: Knowledge of the microbial diversity in a paper mill provides a rational basis for development of an effective controlling programme. A database constructed from the fingerprints generated using automated ribotyping helps to identify and trace the contamination routes of bacteria occurring in paper mills.

Aims: A public beach was frequently cited for health advisories because of high Escherichia coli levels, the source suspected to be a paper mill located upstream. This investigation sought to confirm whether or not the paper mill was the pollution source, and to characterize the risk to recreational bathers imposed by the source., Methods and Results: Quantification of E. coli in river water collected at incremental distances showed that paper mill effluent caused elevated E. coli levels in beach samples. Samples collected throughout the mill were variably positive for heterotrophic bacteria, total coliforms and E. coli, but negative for pathogenic E. coli O157 and Salmonella. Escherichia coli O157 or Salmonella spiked into mill samples (4.2 log(10) or 5.6 log(10) CFU per 100 ml, respectively) fell below detection levels within 14-24 h in raw (unaltered) samples, while in heat-sterilized replicates, the counts remained at initial levels or increased over 36 h., Conclusions: Pathogenic E. coli O157 and Salmonella were not isolated from paper mill samples. The absence of native bacteria allowed the survival of pathogens, while their presence accelerated pathogen decline., Significance and Impact of the Study: The co-existence of paper mill and swimming beach may be reasonable for now in spite of the limitations of an E. coli-based assay for beach water.

Aims: To identify aerobic mesophilic bacteria isolated from coreboard, kitchen roll paper and food packaging boards containing recycled fibres and to create a rapid fingerprint-based database for their identification., Methods and Results: A total of 197 isolates and 20 relevant type strains were characterized by automated ribotyping and as far as possible identified by the similarities of their riboprints to the relevant type strains. One strain from each unidentified ribotype, a total of 87 strains, was subjected to partial 16S rDNA sequencing and in most cases also to fatty acid analysis and physiological tests. From the isolates 113 and seven different ribotypes were generated belonging to the genera Bacillus and Paenibacillus, respectively. The dominating species, or closest related to them, were B. simplex (22.8% of isolates), B. licheniformis (18.3%) and B. amyloliquefaciens (12.7%); 5.1% of the isolates were identified as B. cereus, a potential food-borne pathogen. In particular, this species was present in one food packaging board (26.3% of isolates). Based on these results, 40.1% of the isolates and 45.0% of ribotypes were so different from the relevant type strains that they may represent novel species., Conclusions: All isolates were aerobic spore-formers, indicating that all non-spore-formers were eliminated during the drying stage of the processes. Although many isolates could be affiliated to described species of Bacillus or Paenibacillus, a significant proportion of the isolates could not be identified unambiguously as members of a described species., Significance and Impact of the Study: A RiboPrint identification database, composed of 120 composite patters, was established for bacteria originating from the pulp and paper industry. Considering the discrimination power of ribotyping, this database will be extremely useful in future for the reliable and rapid identification of bacteria isolated from pulp and paper industrial sources.

Aims: A paper by Araújo et al. (2018) claims that a variety of compounds present in pyroligneous acid (guaiacol, phenols and furfural) are responsible for the observed antimicrobial activity. We show, on the other hand, that the low pH due to acetic acid present in pyroligneous acid is the real cause of the activity., Methods and Results: Pyroligneous acid (PA) was synthesized according to a previous method (Medeiros et al. 2019) with its inhibition activity tested on Escherichia coli and Staphylococcus aureus via the agar diffusion method. The activity of acetic acid at different concentrations was also evaluated for comparison. As expected, crude PA (pH 3.0) and acetic acid produced inhibition halos whose diameters varied according to their employed concentration. However, any PA inhibitory activity completely vanished upon neutralization (pH 7.0), a behaviour also observed for neutralized acetic acid., Conclusions: The claim that guaiacol, phenols and furfural are responsible for any inhibitory activity is unsubstantiated. The authors should have neutralized the pyroligneous acid if any activity was to be discovered., Significance and Impact of Study: To increase awareness that interfering species may play a detrimental role on the interpretation of results. In this case, the action of acetic acid is vastly more important for the inhibitory activity than any other compound present in PA., (© 2021 The Society for Applied Microbiology.)

The microbial content of printing paper machines, running at a temperature of 45-50 degrees C and at pH 4.5-5, was studied. Bacteria were prevalent colonizers of the machine wet end and the raw materials. A total of 390 strains of aerobic bacteria were isolated and 86% of these were identified to genus and species by biochemical, chemotaxonomic and phylogenetic methods. The most common bacteria found at the machine wet end were Bacillus coagulans and other Bacillus species, Burkholderia cepacia, Ralstonia pickettii, and in pink slimes, accumulating in the wire area and press section, species of Deinococcus, aureobacterium and Brevibacterium. Paper-making chemicals also contained species of Aureobacterium, B. cereus, B. licheniformis, B. sphaericus, Bordetella, Hydrogenophaga, Klebsiella pneumoniae, Pantoea agglomerans, Pseudomonas stutzeri, Staphylococcus and sometimes other enteric bacteria, but these did not colonize the process water. Yeasts and moulds were not present in significant numbers. A total of 131 strains were tested for their potential to degrade paper-making raw materials; 91 strains were found to have degradative activity, mainly species of Burkholderia and Ralstonia, Sphingomonas and Bacillus, and enterobacteria produced enzymes which degraded paper-making chemicals. Stainless steel adhering strains occurred in slimes and wire water and were identified as Burkholderia cepacia, B. coagulans and Deinococcus geothermalis. Coloured slimes were formed on the machine by species of Deinococcus, Acinetobacter and Methylobacterium (pink), Aureobacterium, Pantoea and Ralstonia (yellowish) and Microbulbifer-related strains (brown). The impact of the strains and species found in the printing paper machine community on the technical quality of paper, machine operation, and as a potential biohazard (Hazard Group 2 bacteria), is discussed.

Aims This study compared the potential for cross contamination of the surrounding environment resulting from two different hand-drying methods: paper towels and the use of an air blade dryer. Methods and results One hundred volunteers for each method washed their hands and dried them using one of the two methods. Bacterial contamination of the surrounding environment was measured using settle plates placed on the floor in a grid pattern, air sampling and surface swabs. Both drying methods produced ballistic droplets in the immediate vicinity of the hand-drying process. The air blade dryer produced a larger number of droplets which were dispersed over a larger area. Settle plates showed increased microbial contamination in the grid squares which were affected by ballistic droplets. Using the settle plates counts, it was estimated that approx. 1·7 × 105 cfu more micro-organisms were left on the laboratory floor (total area approx. 17·15 m2) after 100 volunteers used an air blade dryer compared to when paper towels were used. Conclusions The two drying methods led to different patterns of ballistic droplets and levels of microbial contamination under heavy use conditions. Whilst the increase in microbial levels in the environment is not significant if only nonpathogenic micro-organisms are spread, it may increase the risk of pathogen contamination of the environment when pathogens are occasionally present on people's hands. Significance and Impact of the Study The study suggests that the risk of cross contamination from the washroom users to the environment and subsequent users should be considered when choosing a hand-drying method. The data could potentially give guidance following the selection of drying methods on implementing measures to minimise the risk of cross contamination. [ABSTRACT FROM AUTHOR]

Aims: This study was undertaken to determine the effectiveness of biological indicators currently being employed during formaldehyde decontamination. Data suggest that detectable amounts of formaldehyde are absorbed into the paper strips contained in currently used biological indicators. Absorbed formaldehyde has the potential to inhibit the growth of indicator spores, thus leading to false negative results. Indicators composed of either stainless steel carriers or paper strips were investigated to determine whether stainless steel carriers can be used as an alternative to paper strip indicators., Methods and Results: Biological indicators were exposed to formaldehyde gas and were tested for the presence of formaldehyde and any possible inhibition of spore growth. Absorbed formaldehyde was detected in the paper strip carriers while no formaldehyde was detected from any of the stainless steel carriers. Exposed paper strips were found to inhibit growth of up to 1 × 10(6) spores while the stainless steel carriers did not inhibit the growth of spores., Conclusions: During decontamination, biological indicators composed of paper spore strips absorb formaldehyde and inhibit growth of any surviving spores. Stainless steel carriers do not absorb formaldehyde and are an ideal alternative substrate for biological indicators., Significance and Impact of the Study: The popular paper strip biological indicator can lead to false negative results during decontamination and is unsuitable for validating formaldehyde decontamination., (© 2010 The Authors. Journal of Applied Microbiology © 2010 The Society for Applied Microbiology.)

Aims To use a MS2 bacteriophage model to compare three hand-drying methods, paper towels (PT), a warm air dryer (WAD) and a jet air dryer (JAD), for their potential to disperse viruses and contaminate the immediate environment during use. Methods and Results Participants washed their gloved hands with a suspension of MS2 bacteriophage and hands were dried with one of the three hand-drying devices. The quantity of MS2 present in the areas around each device was determined using a plaque assay. Samples were collected from plates containing the indicator strain, placed at varying heights and distances and also from the air. Over a height range of 0·15-1·65 m, the JAD dispersed an average of >60 and >1300-fold more plaque-forming units (PFU) compared to the WAD and PT ( P < 0·0001), respectively. The JAD dispersed an average of >20 and >190-fold more PFU in total compared to WAD and PT at all distances tested up to 3 m ( P < 0·01) respectively. Air samples collected around each device 15 min after use indicated that the JAD dispersed an average of >50 and >100-fold more PFU compared to the WAD and PT ( P < 0·001), respectively. Conclusions Use of the JAD lead to significantly greater and further dispersal of MS2 bacteriophage from artificially contaminated hands when compared to the WAD and PT. Significance and Impact of Study The choice of hand-drying device should be considered carefully in areas where infection prevention concerns are paramount, such as healthcare settings and the food industry. [ABSTRACT FROM AUTHOR]

Aims: Investigation of waste pulps and soda pulp bleaching with xylanase (X) and laccase mediator system (LMS) alone and in conjunction (one after the other) (XLMS)., Methods and Results: Soda and different grades of waste pulp fibres [used for making three-layered duplex sheets - top layer (TL), protective layer (PL) and bottom layer (BL)] when pretreated with either xylanase (40.0 IU g(-1)) or LMS (up to 200.0 U g(-1)) alone and in combination (one after the other) (XLMS) exhibited an increase in release of reducing sugars [up to 881.0% soda pulp; up to 736.6% (TL), up to 215.7% (PL) and up to 198.0% (BL) waste pulp], reduction in kappa number [up to 17.6% soda pulp; up to 14.0% (TL), up to 25.3% (PL) and up to 10.9% (BL), waste pulp], improvement in brightness [up to 20.4% soda pulp; up to 23.6% (TL), up to 8.6% (PL) and up to 5.0% (BL), waste pulp] when compared with the respective controls. The usage of XLMS along with 15% reduced level of hypochlorite at CEHHXLMS/EHHXLMS bleaching stage reduced kappa number [5.5% soda pulp; 11.4% (TL), 7.9% (PL), waste pulp] and improved brightness [1.0% soda pulp; 0.9% (TL), 1.4% (PL) waste pulp] when compared with the controls. Scanning electron microscopic studies revealed development of cracks, flakes, pores and peeling off the fibres in the enzyme-treated pulp samples. These modifications of the fibre surface during enzymatic bleaching in turn indicated the removal of lignin and derived compounds from the fibre cell wall., Conclusions: The work describes synergistic action of xylanase with LMS for bleaching of waste and nonwood pulps for eco-friendly production of paper and thus reveals a new unexploited arena for enzyme-based pulp bleaching., Significance and Impact of the Study: The drastic improvement in pulp properties obtained after xylanase and LMS treatment would improve the competitiveness of enzyme-based, environmentally benign processes over chemicals both economically and environmentally.

Aims: To determine and quantify the products from the degradation of xylan by a range of purified xylan-degrading enzymes, endoxylanase, beta-xylosidase and alpha-l-arabinofuranosidase produced extracellularly by Thermomonospora fusca BD25., Methods and Results: The amounts of reducing sugars released from oat-spelt xylan by the actions of endoxylanase, beta-xylosidase and alpha-l-arabinofuranosidase were equal to 28.1, 4.6 and 7% hydrolysis (as xylose equivalents) of the substrate used, respectively. However, addition of beta-xylosidase and alpha-l-arabinofuranosidase preparation to endoxylanase significantly enhanced (70 and 20% respectively) the action of endoxylanase on the substrate. The combination of purified endoxylanase, beta-xylosidase and alpha-l-arabinofuranosidase preparations produced a greater sugar yield (58.6% hydrolysis) and enhanced the total reducing sugar yield by around 50%. The main xylooligosaccharide products released using the action of endoxylanase alone on oat-spelt xylan were identified as xylobiose and xylopentose. alpha-l-Arabinofuranosidase was able to release arabinose and xylobiose from oat-spelt xylan. In the presence of all three purified enzymes the hydrolysis products of oat-spelt xylan were mainly xylose, arabinose and substituted xylotetrose with lesser amount of substituted xylotriose., Conclusions: The addition of the beta-xylosidase and alpha-l-arabinofuranosidase enzymes to purified xylanases more than doubled the degradation of xylan from 28 to 58% of the total substrate with xylose and arabinose being the major sugars produced., Significance and Impact of the Study: The results highlight the role of xylan de-branching enzymes in the degradation of xylan and suggest that the use of enzyme cocktails may significantly improve the hydrolysis of xylan in industrial processes.

A haloalkalophilic Staphylococcus sp. SG-13 produced an alkalistable xylanase in wheat bran medium. A 12-fold purification was achieved by using standard purification techniques. The purified xylanase exhibited a dual pH optima of 7.5 and 9.2. The optimum temperature for enzyme activity was 50 degrees C. The enzyme was stable at 50 degrees C for more than 4 h. The xylanase exhibited Km and Vmax values of 4 mg ml-1, 90 micromol min-1 per mg for birchwood xylan and 7 mg ml-1, 55 micromol min-1 per mg for oatspelt xylan, respectively. The substrate binding affinity of xylanase was more for oatspelt xylan but birchwood xylan was hydrolysed more rapidly. The xylanase activity was stimulated by Fe2+, Ni2+, Cu2+ and dithiothreitol up to 60% and was strongly inhibited in the presence of Co2+, Hg2+, Pb2+, phenyl methane sulphonyl fluoride, ethylenediaminetetraacetic acid, and acetic anhydride up to 100%. The xylanase dose of 1.8 U g-1 moisture free pulp, exhibited bleach boosting of kraft pulps optimally at pH 9.5-10.0 and 50 degrees C after 4 h of reaction time. Pretreatment of pulp with xylanase and its subsequent treatment with 8% hypochlorite, reduced the kappa number by 30%, enhanced the brightness and viscosity by 11% and 1.8%, respectively, and improved the paper properties such as tensile strength and burst factor up to 10% and 17%, respectively.

Aims: The purpose of this study was to evaluate the effects of altered environmental conditions on the persistence of Francisella tularensis bacteria and Venezuelan equine encephalitis virus (VEEV), on two material types., Methods and Results: Francisella tularensis (F.t.) and VEEV were inoculated (c. 1 × 10 8 colony-forming units or PFU), dried onto porous and nonporous fomites (glass and paper), and exposed to combinations of altered environmental conditions ranging from 22 to 60°C and 30 to 75% relative humidity (RH). Viability of test organism was assessed after contact times ranging from 30 min to 10 days. Inactivation rates of F.t. and VEEV increased as both temperature and/or RH were increased. Greater efficacy was observed for paper as compared to glass for both test organisms., Conclusions: The use of elevated temperature and RH increased rate of inactivation for both organisms and greater than six log reduction was accomplished in as little as 6 h by elevating temperature to approximately 60°C., Significance and Impact of the Study: These results provide information for inactivation of nonspore-forming select agents using elevated temperature and humidity which may aid incident commanders following a biological contamination incident by providing alternative methods for remediation., (© 2019 The Society for Applied Microbiology.)

Aims The aim of this study was to evaluate the activity of a novel bacterial laccase-like multi-copper oxidase ( LMCO) from Paenibacillus glucanolyticus SLM1: a bacterium isolated from pulp and paper waste. Methods and Results A new bacterial LMCO gene ( CuOx) from P. glucanolyticus SLM1 was identified and cloned into pET22b. The protein it encodes was recombinantly expressed in Escherichia coli. The recombinant P. glucanolyticus LMCO had a molecular weight of approximately 90 kDa and demonstrated oxidation of the LMCO substrates 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonate) ( ABTS), catechol, and 2,6-Dimethoxyphenol (2,6- DMP), with the oxidation of ABTS occurring to the greatest extent (776 U mg−1 under optimal conditions of pH 7 and 40°C). Furthermore, recombinant P. glucanolyticus CuOx retained activity against ABTS in the presence of 1 mol l−1 NaCl, 50% dimethyl sulfoxide and 5% Tween-80 and can decolorize several types of dyes. Conclusions This enzyme has a neutral pH optimum, is capable of decolorizing dyes, and is active in the presence salt, detergents and surfactant. The characteristics of this enzyme suggest that it could be used for a variety of industrial applications. Significance and Impact of the Study This work characterizes a unique bacterial LMCO with activity higher than that of previously characterized fungal or bacterial LMCOs. This enzyme may have utility for industrial bleaching, treatment of dye effluent, and lignin removal. [ABSTRACT FROM AUTHOR]