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Air pollutants are increasingly emitted into the atmosphere because of the high dependency of humans on fossil-derived fuels. Wind speed and direction assisted high dispersibility and uncontrolled nature of air pollution across geo-/demographical borders, making it one of the major global concerns. Besides climate change, air pollution has been found to be associated with various diseases, such as cancer. Lung cancer, which is the world's most common type of cancer, has been found to be associated with traffic-related air pollution. Research and political efforts have been taken to explore green/renewable energy sources. However, these efforts at the current intensity cannot cope with the increasing need for fossil fuels. More specifically, political tensions such as the Russian-Ukraine war, economic tension (e.g., China-USA economic tensions), and other issues (e.g., pandemic, higher inflation rate, and poverty) significantly hindered phasing out fossil fuels. In this context, an increasing global population will be exposed to traffic-related air pollution, which justifies the current uptrend in the number of lung cancer patients. To combat this health burden, novel treatments with higher efficiency and specificity must be designed. One of the potential "life changer" options is microRNA (miRNA)-based therapy to target the expression of oncogenic genes. That said, this review discusses the association of traffic-related air pollution with lung cancer, the changes in indigenous miRNAs in the body during lung cancer, and the current status of miRNA therapeutics for lung cancer treatment. We believe that the article will significantly appeal to a broad readership of oncologists, environmentalists, and those who work in the field of (bio)energy. It may also gain the policymakers' attention to establish better health policies and regulations about air pollution, for example, by promoting (bio)fuel exploration, production, and consumption. [ABSTRACT FROM AUTHOR]

The present study investigates the impact of integrating selective exhaust gas recirculation (SEGR) with a combined cycle gas turbine system (CCGT) and post-combustion capture (PCC) in a model power plant. The impacts of ambient temperature, turbine inlet temperature (TIT), and pressure ratio (PR) on the overall thermal and exergetic efficiencies at component and system levels are evaluated. Results show that the combustion chamber and absorber are the two components with the largest exergy destructions in CCGT and PCC units, with a fraction of 44.8% and 52.9%, respectively. After integrating with SEGR, CO2 concentration in flue gas rises from 3.61 to 6.08%, whereas PCC exergetic efficiency increases by 6%. A design of experiments statistical model was applied through a full factorial design to optimise the responses of minimising total exergy destruction while maximising both the thermal and exergetic efficiencies. The optimised input set for TIT of 1300 °C, PR of 15, and SEGR recycle ratio of 25% leads to the best outcome of 415.08 MW, 56.53%, and 51.04% for total exergy destruction, thermal efficiency, and exergetic efficiency, respectively. The predictor equations produced have high degrees of correlation and predictive capabilities and could be used to form empirical equations to replace thermodynamic calculations entirely. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "Targeting microRNAs as a promising anti-cancer therapeutic strategy against traffic-related air pollution-mediated lung cancer" published in Cancer & Metastasis Reviews. The Editor-in-Chief has issued an editorial expression of concern due to irregularities in authorship and peer review. Additionally, some of the references cited in the article have been retracted. The authors of the article do not agree with this expression of concern. Springer Nature, the publisher, remains neutral in regards to jurisdictional claims and institutional affiliations. [Extracted from the article]

The aim of this study was to obtain a stable flaxseed oil (FSO)-in-water Pickering emulsion (PE) stabilized by chitosan (CS)-myristic acid (MA) nanogels and to investigate the oxidative stability of the CS-MA nanogels-encapsulated FSO in the presence of clove essential oil (CEO) in shell or core modes. First, MA was successfully conjugated to CS by amide linkages in different MA-to-CS ratios to improve the emulsifier property of CS. Subsequently, the effects of pH, MA-to-CS ratio, and oil-to-nanogel ratio on the stability and droplet size of PE were examined. The most stable PE was obtained at pH 8, MA-to-CS ratio of 0.75:1, and oil-to-nanogel ratio of 10:1. Finally, the oxidative stability of the emulsions was analyzed. The results indicated that the formation of the CEO shell around dispersed droplet surfaces of FSO was more efficient in reduction of lipid oxidation and droplet size than admixing CEO in the oil core. The best oxidative stability was observed in the PE with 0.1% CEO shell. Overall, this work showed that by engineering the interfacial architecture via the combination of steric hindrance of CS-MA nanogel-based membrane and the interfacial load of CEO, appropriate physical and oxidative stabilities of the emulsions were obtainable. [ABSTRACT FROM AUTHOR]

In this study, water-soluble carbon nanoparticles (CNPs) were synthesized by using waste facial tissue as a non-recyclable waste and the efficiency of CNPs in quenching mechanism of cadmium-telluride quantum dots (QDs) was investigated. In addition, CNPs synthesis was modeled by using artificial neural networks (ANN). To find the optimum model, ANN was trained by using different algorithms. Then, the generated models were statistically assessed and subsequently, the capability of the selected model for predicting the mean diameter size of the nanoparticles was verified. Based on the results, the model GA-4-7-1 had the most optimal statistical characteristics. Furthermore, the most pronounced effect on mean diameter size was associated to HNO3 concentration while temperature demonstrated the least influence. Moreover, the quenching study confirmed the capability of the synthesized CNPs in quenching QDs. [ABSTRACT FROM AUTHOR]

Purpose: Diminishing fossil resources and environmental concerns associated with their vast utilization have been in focus by energy policy makers and researchers. Among the different scenarios put forth to commercialize biofuels, various biorefinery concepts have aroused global interests because of their ability in converting biomass into a spectrum of marketable products and bioenergies. This study was aimed at developing different novel castor-based biorefinery scenarios for generating biodiesel and other co-products, i.e., ethanol and biogas. In these scenarios, glycerin, heat, and electricity were also considered as byproducts. Developed scenarios were also compared with a fossil reference system delivering the same amount of energy through the combustion of neat diesel.Materials and methods: Life cycle assessment (LCA) was used to investigate the environmental consequences of castor biodiesel production and consumption with a biorefinery approach. All the input and output flows from the cultivation stage to the combustion in diesel engines as well as changes in soil organic carbon (SOC) were taken into account. Impact 2002+ method was used to quantify the environmental consequences.Results and discussion: The LCA results demonstrated that in comparison with the fossil reference system, only one scenario (i.e., Sc-3 with co-production of significant amounts of biodiesel and biomethane) had 16% lower GHG emissions without even considering the improving effect of SOC. Moreover, resource damage category of this scenario was 50% lower than that of neat diesel combustion. The results proved that from a life cycle perspective, energy should be given priority in biorefineries because it is essential for a biorefinery to have a positive energy balance in order to be considered as a sustainable source of energy. Despite a positive effect on energy and GHG balances, these biorefineries had negative environmental impacts on the other damage categories like Human Health and Ecosystem Quality.Conclusions: Although biorefineries offer unique features as promising solutions for mitigating climate change and reducing dependence on fossil fuels, the selection of biomass processing options and management decisions can affect the final results in terms of environmental evaluations and energy balance. Moreover, if biorefineries are focused on transportation fuel production, a great deal of effort should still be made to have better environmental performance in Human Health and Ecosystem Quality damage categories. This study highly recommends that future studies focus towards biomass processing options and process optimization to guarantee the future of the most sustainable biofuels. [ABSTRACT FROM AUTHOR]

Two strains of true branched heterocytous cyanobacteria, SA33 and SA16, isolated from dried paddy fields of Mazandaran, Iran, were studied using morphological, ecological, and molecular tools. Morphological characterization of the strains indicated them to be commonly showing profuse T-type branching, large irregularly shaped cells of main filament and tapering branches. Strain SA33 showed development of interesting biseriate filaments with unilateral branching, while strain SA16 showed uniseriate filaments with bilateral branching. Ecological examination of the localities consisted of the assessment of the habitat and correlations with the overall environment of the habitats. 16S rRNA gene-based molecular and phylogenetic assessment gave unique positioning to both the strains separated with good bootstrap support from rest of the members of the true branched clade. Full length sequencing of the 16S-23S ITS region and folding of the secondary structures gave interesting secondary structures and comparison with the closely related sequences clearly indicated the secondary structures of both the strains to be unique. All the results indicated the strains to be members of a morphologically cryptic but phylogenetically distinct unknown genus of cyanobacteria. Comprehensive evaluation of all the findings and comparative assessment of previous studies indicate that SA33 and SA16 are indeed two new species of a new genus of true branched cyanobacteria. In accordance with the International Code of Nomenclature for algae, fungi and plants, we propose the name of the new genus as Neowestiellopsis with the names of the species being Neowestiellopsis persica and Neowestiellopsis bilateralis. [ABSTRACT FROM AUTHOR]

Cadmium-telluride quantum dots (QDs) were conjugated to an antibody (Ab) against Citrus tristeza virus (CTV), while the coat protein (CP) of the CTV was immobilized on the surface of carbon nanoparticles (CNPs). Following immunobinding of the QD-Ab and the CP-loaded CNPs, the fluorescence of the CdTe QDs was quenched by the CNPs. This effect was exploited to design a detection assay for the CTV which was found more sensitive and specific than the existing enzyme linked immunosorbent assay (ELISA). The limit of detection was measured at about 220 ng⋅ mL‾ of CTV. The Stern-Volmer plot of the CNPs-QD quencher pair showed a positive deviation from linearity which was ascribed to the presence of both static and dynamic quenching. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The present study was set to develop a robust and economic biorefinery process for continuous co-production of ethanol and xylitol from rice straw in a membrane bioreactor. Acid pretreatment, enzymatic hydrolysis, detoxification, yeast strains selection, single and co-culture batch fermentation, and finally continuous co-fermentation were optimized. The combination of diluted acid pretreatment (3.5 %) and enzymatic conversion (1:10 enzyme (63 floating-point unit (FPU)/mL)/biomass ratio) resulted in the maximum sugar yield (81 % conversion). By concentrating the hydrolysates, sugars level increased by threefold while that of furfural reduced by 50 % (0.56 to 0.28 g/L). Combined application of active carbon and resin led to complete removal of furfural, hydroxyl methyl furfural, and acetic acid. The strains Saccharomyces cerevisiae NCIM 3090 with 66.4 g/L ethanol production and Candida tropicalis NCIM 3119 with 9.9 g/L xylitol production were selected. The maximum concentrations of ethanol and xylitol in the single cultures were recorded at 31.5 g/L (0.42 g/g yield) and 26.5 g/L (0.58 g/g yield), respectively. In the batch co-culture system, the ethanol and xylitol productions were 33.4 g/L (0.44 g/g yield) and 25.1 g/L (0.55 g/g yield), respectively. The maximum ethanol and xylitol volumetric productivity values in the batch co-culture system were 65 and 58 % after 25 and 60 h, but were improved in the continuous co-culture mode and reached 80 % (55 g/L) and 68 % (31 g/L) at the dilution rate of 0.03 L per hour, respectively. Hence, the continuous co-production strategy developed in this study could be recommended for producing value-added products from this hugely generated lignocellulosic waste. [ABSTRACT FROM AUTHOR]

In this paper, the exergetic performance of a continuous bioreactor for ethanol and acetate synthesis from syngas via a strictly anaerobic autotrophic bacterium Clostridium ljungdahlii was carried out for the first time. The fermentation process was evaluated using both conventional exergy and eco-exergy principles for measuring the productivity and renewability of the process at various liquid media flow rates. The microorganisms successfully upgraded the syngas into invaluable ethanol and acetate through the Wood-Ljungdahl pathway. The exergy efficiency was found to be in the range of 6.5-77.5 and 6.8-77.5 % during the fermentation using conventional exergy and eco-exergy concepts, respectively. The subtle differences observed in the exergetic parameters using the two exergetic concepts were ascribed to the slow growth rate of the microorganisms. Nevertheless, the eco-exergy concept would strongly be recommended for commercial bioreactor containing living organisms due to the inclusion of the information carried by microorganisms in the exergetic calculation. A desired liquid media flow rate of 0.55 mL/min was found according to a newly defined thermodynamic indictor namely exergetic productivity index. More specifically, the maximum exergetic productivity index of the fermentation process was found to be 8.0 using both approaches when the rate of inflow liquid was adjusted at the optimal value. The results of this study revealed that process yield alone cannot be a reliable performance metric for decision making on the productivity of various biofuel production pathways. Finally, the proposed exergetic framework could assist engineers and researchers to link biochemical and physical knowledge more robustly and to quantify and elucidate the general purpose of productivity and renewability. [ABSTRACT FROM AUTHOR]

Combined pretreatment methods for improving sugar yield as well as the economic aspects of lignoethanol production processes have gained a great deal of interest. However, most investigations involving such methods have been conducted under optimum conditions. Such fully-optimized combinations although improve enzymatic digestion, they could also degrade cellulose structure resulting in reduced sugar yield in some cases. The present study was set to prepare rice straw for the 1-ethyl-3-methylimidazolium acetate pretreatment step (2 h, 120 °C), by mild alkaline extraction (30 min, 80 °C, 0.3 % NaOH) with a focus on only 30 % lignin removal to minimize the hemicelluloses degradation. Moreover, the effect of size reduction (<0.42 mm and <2 cm) was also investigated. The results showed that the novel combination method based on only 30 % lignin removal led to an increased sugar yield by 17 %. Unexpectedly, although IL pretreatment needs material to be ground (<0.42 mm), the difference in sugar yields for the two sized tested was negligible. Graphical Abstract: The overall lignocellolusic bioethanol production pathway including the combined AE-IL process proposed in the present study based on 30 % lignin removal through the first AE step.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A systematic optimization process for simple and eco-friendly extracellular biosynthesis of gold nanoparticles by a native thermophilic Ureibacillus thermosphaericus strain thermo-BF isolated from geothermal hot springs has been presented. Biosynthesis reactions were conducted using the culture supernatant at different temperatures (60-80 °C) and pH (6-9) with gold ion concentration ranging from 0.001 to 0.1 M. The results obtained showed that pure spherical nanoparticles in the range of 35-75 nm were produced, and the maximum nanoparticle production was achieved using 0.001 M HAuCl at 80 °C, pH 9. Genome mining and profiling of the genes encoding bioreducing enzymes in U. hermosphaericus strain thermo-BF revealed evidences indicating sulfur reduction capability of this bacterium. Overall, the findings of this study confirmed the great biocatalyzing potential of the extermophilic U. thermosphaericus strain thermo-BF supernatant for intensified biosynthesis of gold nanoparticle under extreme conditions. [ABSTRACT FROM AUTHOR]

Organophosphorus (OP) compounds are extensively used in agricultural practice for pest management. However, their residues have a long half-life in the ecosystem as well as in the agro-products, posing a serious threat to human and animal health. Aryldialkylphosphatase (EC 3.1.8.1) is widely used in detoxification procedures. In the present study, aryldialkylphosphatase was immobilised on synthesised cross-linked nano-sized gel particles, also known as nanogels, in order to enhance the enzyme's physicochemical properties. Accordingly, a new nanogel consisting of chitosan and myristic acid (CMA nanogel) was synthesised and characterised by way of Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The aryldialkylphosphatase-CMA nanogel conjugate was then assayed by FTIR, and its physicochemical characteristics were also investigated. The data obtained from SEM and TEM showed the nanogels to be homogenous spherical particles less than 50 nm in diameter. The proper formation of the nanogel and nanobioconjugate was also confirmed by FTIR spectra. In comparison with the free enzyme, the pH and thermal stability of the aryldialkylphosphatase were enhanced by the covalent immobilisation. Moreover, the immobilised enzyme could maintain approximately half of its activity over more than one month. The kinetic parameters of the aryldialkylphosphatase- CMA nanogel conjugate were also shown to undergo remarkable improvements, hence the synthesised CMA-nanogel could act as a promising support for aryldialkylphosphatase immobilisation. It is suggested that the aryldialkylphosphatase-CMA nanogel could be used for detoxifying paraoxon; a nerve agent. Further clinical experiments are underway. [ABSTRACT FROM AUTHOR]

Rapid detection of organophosphorous (OP) compounds such as paraoxon would allow taking immediate decision on efficient decontamination procedures and could prevent further damage and potential casualties. In the present study, a biosensor based on nanomagnet-silica core-shell conjugated to organophosphorous hydrolase (OPH) enzyme was designed for detection of paraoxon. Coumarin1, a competitive inhibitor of the OPH enzyme, was used as a fluorescence-generating molecule. Upon excitation of cumarin1 located at the active site of the enzyme, i.e., OPH, the emitted radiations were intensified due to the mirroring effect of the nanomagnet-silica core-shell conjugated to the enzyme. In presence of paraoxon and consequent competition with the fluorophore in occupying enzyme's active site, a significant reduction in emitted radiations was observed. This reduction was proportional to paraoxon concentration in the sample. The method worked in the 10- to 250-nM concentration range had a low standard deviation (with a coefficient of variation (CV) of 6-10 %), and the detection limit was as low as 5 × 10 μM. [ABSTRACT FROM AUTHOR]

Biotechnology-based detection systems and sensors are in use for a wide range of applications in biomedicine, including the diagnostics of viral pathogens. In this review, emerging detection systems and their applicability for diagnostics of viruses, exemplified by the case of avian influenza virus, are discussed. In particular, nano-diagnostic assays presently under development or available as prototype and their potentials for sensitive and rapid virus detection are highlighted. [ABSTRACT FROM AUTHOR]

The aim of this study was to coat and change the surface properties of the PES membranes to increase the membrane performance. Accordingly, we coated a layer of chitosan on a PES membrane and then modified the created layer by acrylic acid and microwave irradiation for the first time. The fabricated layer was modified by acrylic acid (AA) as a grafting agent using a household microwave apparatus without any initiator. Different concentrations of AA and irradiation power as well as irradiation times were studied for the purpose. The obtained membranes were characterized using SEM, AFM, ATR-FTIR, contact angle, cross flow filtration, and anti-fouling property measurements. SEM images showed both the formation of a chitosan-coated PES membrane under the procedure and the resultant alterations in the surface structure. Based on the results, a moderate concentration of AA could enhance the coated layer properties and the rejection capability as well as the antifouling properties of the obtained membranes. AFM images represented the changes in the nanostructure of the coated layers as well as the surface characteristics. Accordingly, the mean surface pore sizes of the obtained membranes were reduced down to 35 nm after modification calculated by SPM-DME software. The antifouling properties of the modified membranes using bovine serum albumin (BSA) as a protein pattern showed that the flux recovery ratio (FRR) of some membranes increased by three times more than that of the unmodified membrane. [ABSTRACT FROM AUTHOR]

Identification of resistance resources of sugar beet germplasm against Polymyxa betae has always been a critical concern among sugar beet breeders. In the present study, two different methods including the DAS-enzyme-linked immunosorbent assay (ELISA) test and a nanobiosensor method based on florescent resonance transfer energy (FRET) were compared in order to achieve resistant germplasm. More specifically, 58 sugar beet germplasm as well as two negative and two positive controls were cultivated in infested soil under greenhouse conditions. The contamination level or in another words sensitivity and specificity observed based on the ELISA readings was inaccurately lower in comparison with the investigated nanobiosensor. Moreover, the nanobiosensor was 70 folds less time consuming compared to the ELISA method, for the immuno-reaction was much faster and no sample treatment steps were required. As a result, the quantum dots-FRET-based nanobiosensor investigated herein could well suit the task of everyday screening of resistance resource and could be efficiently used in breeding programs. [ABSTRACT FROM AUTHOR]

Biohydrogen production through water-gas shift (WGS) reaction by a biocatalyst was conducted in batch fermentation. The isolated photosynthetic bacterium Rhodopseudomonas palustris PT was able to utilize carbon monoxide and simultaneously produce hydrogen. Light exposure was provided as an indispensable requirement for the first stage of bacterial growth, but throughout the hydrogen production stage, the energy requirement was met through the WGS reaction. At ambient pressure and temperature, the effect of various sodium acetate concentrations in presence of CO-rich syngas on cell growth, carbon monoxide consumption, and biohydrogen production was also investigated. Maximal efficiency of hydrogen production in response to carbon monoxide consumption was recorded at 86 % and the highest concentration of hydrogen at 33.5 mmol/l was achieved with sodium acetate concentration of 1.5 g/l. The obtained results proved that the local isolate; R. palustris PT, was able to utilize CO-rich syngas and generate biohydrogen via WGS reaction. [ABSTRACT FROM AUTHOR]

A dimeric organophosphorus hydrolase (OPH; EC 3.1.8.1; 72 kDa) was isolated from wild-type bacteria, analyzed for its 16s rRNA sequence, purified, and immobilized on gold nanoparticles (AuNPs) to form the transducer part of a biosensor. The isolated strain was identified as Pseudomonas aeruginosa. The AuNPs were characterized by transmission electron microscopy and localized surface plasmon resonance. Covalent binding of OPH to the AuNPs was confirmed by spectrophotometry, enzymatic activity assays, and FTIR spectroscopy. Coumarin 1, a competitive inhibitor of OPH, was used as a fluorogenic probe. The bioconjugates quench the emission of coumarin 1 upon binding, but the addition of paraoxon results in an enhancement of fluorescence that is directly proportional to the concentration of paraoxon. The gold-OPH conjugates were then used to determine paraoxon in serum samples spiked with varying levels of paraoxon. The method works in the 50 to 1,050 nM concentration range, has a low standard deviation (with a CV of 5.7-11 %), and a detection limit as low as 5 × 10 M. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

We report on a competitive immunoassay for the determination of aflatoxin B1 using fluorescence resonance energy transfer (FRET) from anti-aflatoxin B1 antibody (immobilized on the shell of CdTe quantum dots) to Rhodamine 123 (Rho 123-labeled aflatoxin B1 bound to albumin). The highly specific immunoreaction between the antibody against aflatoxin B1 on the QDs and the labeled-aflatoxin B1 brings the Rho 123 fluorophore (acting as the acceptor) and the QDs (acting as the donor) in close spatial proximity and causes FRET to occur upon photoexcitation of the QDs. In the absence of unlabeled aflatoxin B1, the antigen-antibody complex is stable, and strong emission resulting from the FRET from QDs to labeled aflatoxin B1 is observed. In the presence of aflatoxin B1, it will compete with the labeled aflatoxin B1-albumin complex for binding to the antibody-QDs conjugate so that FRET will be increasingly suppressed. The reduction in the fluorescence intensity of the acceptor correlates well with the concentration of aflatoxin B1. The feasibility of the method was established by the detection of aflatoxin B1 in spiked human serum. There is a linear relationship between the increased fluorescence intensity of Rho 123 with increasing concentration of aflatoxin B1 in spike human serum, over the range of 0.1-0.6 μmol·mL. The limit of detection is 2 × 10 M. This homogeneous competitive detection scheme is simple, rapid and efficient, and does not require excessive washing and separation steps. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Developing a reliable technique to transform unicellular green algae, Chlorella vulgaris, could boost potentials of using microalgae feedstock in variety of applications such as biodiesel production. Volumetric lipid productivity (VLP) is a suitable variable for evaluating potential of algal species. In the present study, the highest VLP level was recorded for C. vulgaris (79.08 mg lday) followed by 3 other strains studied; C. emersonii, C. protothecoides, and C. salina by 54.41, 45 and 18.22 mg lday, respectively. Having considered the high productivity of C. vulgaris, it was selected for the preliminary transformation experiment through micro-particle bombardment. Plasmid pBI 121, bearing the reporter gene under the control of CaMV 35S promoter and the kanamycin marker gene, was used in cells bombardment. Primary selection was done on a medium supplemented by 50 mg l kanamycin. After several passages, the survived cells were PCR-tested to confirm the stability of transformation and then were found to exhibit β-glucuronidase (GUS) activity in comparison with the control cells. Southern hybridization of npt II probe with genomic DNA revealed stable integration of the cassette in three different positions in the genome. The whole process was successfully implemented as a pre-step to transform the algal cells by genes involved in lipid production pathway which will be carried out in our future studies. [ABSTRACT FROM AUTHOR]

Although biodiesel has been known as an alternative fuel with specific advantages, it has also been investigated as a bio-solvent. In this study, biodiesel was applied as a bio-solvent for expanded polystyrene (EPS) and the kinetics of polymers' dissolution in biodiesel was also investigated. Physicochemical parameters such as solubility parameters of EPS and biodiesel as well as polymer-solvent interaction were calculated at 21.13, 18.19 (MPa) and 0.343, respectively. From the energy recovery point of view, different parameters i.e. flash point, density, kinematic viscosity and dynamic viscosity were evaluated for the waste polymer-biodiesel blended diesel fuel. The results obtained revealed that the addition of EPS improved the biodiesel blended diesel fuel by increasing the flash point value while reducing the density and viscosity values. Moreover, the addition EPS alone generally increased the cloud point values, but co-addition of EPS and co-solvent (acetone) partially restored them to the original values. The overall engine test results were also in favor of the fuel blend as fuel consumption and emissions i.e. CO, CO, NOx and smoke reduced considerably while the power generated remained approximately constant. [ABSTRACT FROM AUTHOR]

A new isolate designated as strain EB172 was isolated from a digester treating palm oil mill effluent and was investigated by polyphasic taxonomic approach. The cells were rod-shaped, Gram-negative, non-pigmented, non-spore-forming and non-fermentative. Phylogenetic analysis using the 16S rRNA gene sequence showed that the strain clustered with the genus Comamonas. Its closest neighbours were the type strains Comamonas terrigena (96.8%), Comamonas koreensis (93.4%), Comamonas composti (92.9%), and Comamonas kerstersii (91.1%). The ability of the strain EB172 to produce polyhydroxyalkanoates (PHA) when supplied with organic acids made this bacterium unique among Comamonas species. The bacterial strain was clearly distinguished from all of the existing strains by phylogenetic analysis, fatty acid composition and a range of physiological and biochemical characteristics. The G +C content of the genomic DNA was 59.1 mol%. The strain showed good growth in acetic, propionic and n-butyric acids. Comamonas sp. EB172 produced 9.8 g/l of cell dry weight and accumulated 59 (wt%) of PHAs when supplemented with mixed organic acids from anaerobically treated palm oil mill effluent. It is evident from the genotypic, phenotypic data and ability to produce PHAs that strain EB172 represents a new strain in the genus Comamonas (GeneBank accession no. EU847238). [ABSTRACT FROM AUTHOR]