Molecular Dynamics Simulation of the Rejuvenation Performance of Waste Cooking Oil with High Acid Value on Aged Asphalt.

Waste cooking oil's (WCO's) potential as a rejuvenator of aged asphalt has received attention in recent years, with the acid value of WCO affecting its rejuvenation effect. This study explored the rejuvenation effect of WCO with a high acid value on aged asphalt by using molecular dynamics simulation. First, the representative molecules of WCO with a high acid value and asphalt were determined. The rejuvenation effect of WCO on aged asphalt was analyzed by adding different contents of WCO to an aged asphalt model. The effect of WCO on the thermodynamic properties of the aged asphalt was analyzed. The results show that WCO can restore the thermodynamic properties of aged asphalt binder to a certain extent. Regarding the microstructure of rejuvenated asphalt, WCO molecules dispersed around asphaltenes weakened the latter's aggregation and improved the colloidal structure of the aged asphalt. In terms of interface adhesion properties, WCO can improve the adhesion properties between asphalt binder and SiO2, but it has limited influence on water sensitivity. The results allowed us to comprehensively evaluate the rejuvenation effect of WCO with a high acid value on aged asphalt and to explore its rejuvenation mechanism.

Chemical and biological evaluation of biosurfactant fractions from Wickerhamomyces anomalus CCMA 0358.

Biosurfactants (BS) are becoming a solution for today's world since they are considered a reasonable and eco-friendly option for use in products that require surfactants. This study aimed to evaluate the antibacterial activity of purified fractions containing biosurfactants produced by the yeast Wickerhamomyces anomalus CCMA 0358 using waste cooking oil (WCO) as substrate. Mixed fractions were separated and characterized by TLC, MPLC, GC-MS, LC-OMS, LC-SQMS, FTIR, 1H, 13C, DEPT 135, COSY, HSQC, and HMBC. The results confirmed the presence of palmitic acid and oleic acid fatty acids, derived from the core biosurfactant structure; however, the core could not be identified. The crude biosurfactant and its purified fractions were evaluated against pathogenic bacteria, and the purified fractions of the biosurfactant are more efficient at inhibitory and bactericidal activities than the crude biosurfactant. To the best of our knowledge, this is the first study that evaluated the antimicrobial activity of purified fractions of biosurfactants produced by the species Wickerhamomyces anomalus. Therefore, the purification of biosurfactants can emerge as an interesting alternative to increase the bioactivity of the compounds and ensure greater efficiency and biotechnological employability. KEY POINTS: • Successful production of a biosurfactant using a renewed carbon source. • Evaluation of the antimicrobial activity of purified fractions of BS. • Separated fractions of the BS are more efficient against bacteria than the crude BS.

Applications of an electronic nose in the prediction of oxidative stability of stored biodiesel derived from soybean and waste cooking oil.

Waste cooking oil (WCO) is a valuable feedstock for the synthesis of biodiesel but the product exhibits poor oxidative stability. Techniques available for assessing this parameter are generally expensive and time-consuming, hence the purpose of this study was to develop and validate a rapid and reliable predictive system based on signals from the sensors of a commercial hand-held e-nose instrument. Biodiesels were synthesized from soybean oil and six samples of WCO, and their physicochemical characteristics and oxidative stabilities determined before and after storage in different types of containers for 30 or 60 days at room temperature or 43 °C. Linear regression models were constructed based on principal component analysis of the signals generated by all 32 e-nose sensors and stochastic modeling of signal profiles from individual sensors. The regression model with principal components as predictors was unable to explain the oxidative stability of biodiesels, while the regression model with stochastic parameters (combining signals from 11 sensors) as predictors showed an excellent goodness of fit (R2 = 0.91) with a 45-sample training set and a good quality of prediction (R2 = 0.84) with a 18-sample validation set. The proposed e-nose system was shown to be accurate and efficient and could be used to advantage by producers/distributors of biodiesel in the assessment fuel quality.

Advanced process integration for supercritical production of biodiesel: Residual waste heat recovery via organic Rankine cycle (ORC).

Biodiesel production using supercritical methanolysis has received immense interest over the last few years. It has the ability to convert high acid value feedstock into biodiesel using a single-pot reaction. However, the energy intensive process is the main disadvantage of supercritical biodiesel process. Herein, a conceptual design for the integration of supercritical biodiesel process with organic Rankine cycle (ORC) is presented to recover residual hot streams and to generate electric power. This article provides energy and techno-economic comparative study for three developed scenarios as follows: original process with no energy integration (Scenario 1), energy integrated process (Scenario 2) and advanced energy integrated process with ORC (Scenario 3). The developed integrated biodiesel process with ORC resulted in electric power generation that has not only satisfied the process electric requirement but also provided excess power of 257 kW for 8,000 tonnes/annum biodiesel plant. The techno-economic comparative analysis resulted in favouring the third scenario with 36% increase in the process profitability than the second scenario. Sensitivity analysis has shown that biodiesel price variation has significant effect on the process profitability. In summary, integrating supercritical biodiesel production process with ORC appears to be a promising approach for enhancing the process techno-economic profitability and viability.

Recent advances in one-stage conversion of lipid-based biomass-derived oils into fuel components - aromatics and isomerized alkanes.

Nowadays, production of biofuels is a rather hot topic due to depleting of conventional fossil fuel feedstocks and a number of other factors. Plant lipid-based feedstocks are very important for production of diesel-, kerosene-, and gasoline-like hydrocarbons. Usually, (hydro)deoxygenation processes are aimed at obtaining of linear hydrocarbons known to have poor fuel characteristics compared to the branched ones. Thus, further hydroisomerization is required to improve their properties as motor fuel components. This review article is focused on conversion of lipid-based feedstocks and model compounds into high-quality fuel components for a single step - direct cracking into aromatics and merged hydrodeoxygenation-hydroisomerization to obtain isoparaffins. The second process is quite novel and a number of the research articles presented in the literature is relatively low. As auxiliary subsections, hydroisomerization of straight hydrocarbons and techno-economic analysis of renewable diesel-like fuel production are briefly reviewed as well.

Oil from transgenic Camelina sativa containing over 25 % n-3 long-chain PUFA as the major lipid source in feed for Atlantic salmon (Salmo salar).

Facing a bottleneck in the growth of aquaculture, and a gap in the supply and demand of the highly beneficial n-3 long-chain PUFA (LC-PUFA), sustainable alternatives to traditional marine-based feeds are required. Therefore, in the present trial, a novel oil obtained from a genetically engineered oilseed crop, Camelina sativa, that supplied over 25 % n-3 LC-PUFA was tested as a sole dietary-added lipid source in Atlantic salmon (Salmo salar) feed. Three groups of fish were fed three experimental diets for 12 weeks with the same basal composition and containing 20 % added oil supplied by either a blend of fish oil and rapeseed oil (1:3) (COM) reflecting current commercial formulations, wild-type Camelina oil (WCO) or the novel transgenic Camelina oil (TCO). There were no negative effects on the growth, survival rate or health of the fish. The whole fish and flesh n-3 LC-PUFA levels were highest in fish fed TCO, with levels more than 2-fold higher compared with those of fish fed the COM and WCO diets, respectively. Diet TCO had no negative impacts on the evaluated immune and physiological parameters of head kidney monocytes. The transcriptomic responses of liver and mid-intestine showed only mild effects on metabolism genes. Overall, the results clearly indicated that the oil from transgenic Camelina was highly efficient in supplying n-3 LC-PUFA providing levels double that obtained with a current commercial standard, and similar to those a decade ago before substantial dietary fishmeal and oil replacement.

Biodiesel production as a solution to waste cooking oil (WCO) disposal. Will any type of WCO do for a transesterification process? A quality assessment.

Biodiesel production can be the solution to the problem of how to deal with waste cooking oils (WCO) and the associated problem of environmental contamination. Every year, tonnes of WCO are poured into toilets and drains, contaminating water supplies and creating serious problems in waste water treatment plants. WCO is a waste material that can be used to produce biodiesel. The main aim of this study is to determine how the type of WCO (and how much it has been used) affect the quality of the biodiesel obtained. Four types of WCO (sunflower, maize, olive and a blend of soybean, palm and sunflower) with two different levels of degradation were used to produce biodiesel. The WCO were subjected to a transesterification process, using NaOH and methanol as reagents, reaction temperatures of between 50 and 67.5 °C, a 60 min reaction time and magnetic stirring. The quality of the biodiesel that was obtained was measured on the basis of four parameters as set out in the UNE-EN 14214 standard: density at 15 °C, kinematic viscosity at 40 °C, acid number and iodine value. This characterisation forms part of the second aim of this research, namely to determine which types of WCO can produce a quality biodiesel via a single stage transesterification process. The results show that the biodiesel quality is closely related to that of the WCO, and that the transesterification method can be recommended for WCO with densities (at 15 °C) of up to 930 kg/m3, kinematic viscosity (at 40 °C) of up to 38.46 mm2/s, and acid numbers of up to 4.19 mg KOH/g. The production method used is a simple, economic and effective way of adding value to a hazardous and difficult to manage waste material like WCO.

Effect of Crystallinity on the Field Emission Characteristics of Carbon Nanotube Grown on W-Co Bimetallic Catalyst.

Carbon nanotube (CNT) is an excellent field emission material. However, uniformity and stability are the key issues hampering its device application. In this work, a bimetallic W-Co alloy was adopted as the catalyst of CNT in chemical vapor deposition process. The high melting point and stable crystal structure of W-Co helps to increase the grown CNT diameter uniformity and homogeneous crystal structure. High-crystallinity CNTs were grown on the W-Co bimetallic catalyst. Its field emission characteristics demonstrated a low turn-on field, high current density, stable current stability, and uniform emission distribution. The Fowler-Nordheim (FN) and Seppen-Katamuki (SK) analyses revealed that the CNT grown on the W-Co catalyst has a relatively low work function and high field enhancement factor. The high crystallinity and homogeneous crystal structure of CNT also reduce the body resistance and increase the emission current stability and maximum current. The result provides a way to synthesis a high-quality CNT field emitter, which will accelerate the development of cold cathode vacuum electronic device application.

Experimental design and analysis of advanced three phase converter for PV application with WCO-P&O MPPT controller.

Photovoltaic (PV)-based power generation systems are becoming increasingly popular as a due to its high performance and cleanliness. Several factors influence the performance of a PV system, including shadowing effects. PV systems employ MPPT methodologies to obtain the power from PV array. Conventional MPPTs works well under normal conditions when there is no shadow effects or partial shading. The presence of partial shading affects the system performance and generates several power peaks. This complicates the process of finding out of the global peak (GMPP) with improved tracking efficiency and reduced settling time including conversion efficiency. This work proposes three hybrid MPPT techniques: Water Cycle Optimisation-Perturb and Observe (WCO-PO), Artificial Neural Network Supported Adaptable Stepped-Scaled Perturb and Observe (ANN-ASSPO), Grey Wolf Optimisation-Modified Fast Terminal Sliding Mode Controller (GWO-MFTSMC), and two conventional MPPT techniques WCO and P&O have been implemented. The proposed system utilizes interleaved boost converter with three phase. The performances of proposed hybrid MPPTs strategies were compared in terms of output voltage, output current and extracted power. The comparison also includes conversion efficiency and average settling time. To analyse the performances, four different cases have been used to test the efficacy of hybrid MPPTs under changing climatic conditions. The MATLAB/Simulink tool has been used to analyze the PV system performances. In the three hybrid MPPT techniques, WCO-PO has performed better when compared to other two hybrid MPPTs in terms of conversion efficiency (99.56%) and settling time (1.4 m).

Effect of Sasobit/Waste Cooking Oil Composite on the Physical, Rheological, and Aging Properties of Styrene-Butadiene Rubber (SBR)-Modified Bitumen Binders.

The modifying effects of polymer on bitumen low-temperature performance are substantially compromised by the thermal breakdown of styrene-butadiene rubber (SBR) polymer during bitumen mixture production operations. The efficacy of the utilization of Sasobit/waste cooking oil (Sasobit/WCO) as a warm-mix additive has been demonstrated in mitigating the adverse consequences of thermal aging on SBR-modified bitumen binder (SB) while preserving the binder's original performance characteristics. However, few studies have been conducted to further investigate the rheological properties and aging resistance of SB modified with Sasobit/WCO compounds. In this work, three additives-Sasobit, WCO, and Sasobit/WCO composite-were selected, and their effects on the physical and rheological characteristics of SB as well as the temperatures at which the mixtures were prepared were assessed. In addition, by using dynamic shear rheometers (DSR) and bending beam rheometers (BBR), the effects of this innovative warm-mix addition on the performance grade (PG) and aging resistances of SB were evaluated. According to the results, Sasobit/WCO composites outperform Sasobit and WCO in lowering the mixture preparation temperature. Sasobit/WCO also improves both the high- and low-temperature performance of SB simultaneously. Compared to hot-mix asphalt mixtures, the addition of Sasobit/WCO reduces the preparation temperature of the bitumen mixtures by 19 °C, which in turn helps to minimize the negative effects of temperature aging on the functioning of the SB. Additionally, the Sasobit/WCO composite addition can improve the SB mixture's resistance to thermal cracking. After the introduction of Sasobit/WCO, the high-temperature PG of SB was raised by two levels, regardless of whether the warm-mix impact was taken into account. With the addition of Sasobit/WCO, SB's resilience to short-term aging was enhanced.

Biodegradation of Oil by a Newly Isolated Strain Acinetobacter junii WCO-9 and Its Comparative Pan-Genome Analysis.

Waste oil pollution and the treatment of oily waste present a challenge, and the exploitation of microbial resources is a safe and efficient method to resolve these problems. Lipase-producing microorganisms can directly degrade waste oil and promote the degradation of oily waste and, therefore, have very significant research and application value. The isolation of efficient oil-degrading strains is of great practical significance in research into microbial remediation in oil-contaminated environments and for the enrichment of the microbial lipase resource library. In this study, Acinetobacter junii WCO-9, an efficient oil-degrading bacterium, was isolated from an oil-contaminated soil using olive oil as the sole carbon source, and its enzyme activity of ρ-nitrophenyl decanoate (ρ-NPD) decomposition was 3000 U/L. The WCO-9 strain could degrade a variety of edible oils, and its degradation capability was significantly better than that of the control strain, A junii ATCC 17908. Comparative pan-genome and lipid degradation pathway analyses indicated that A. junii isolated from the same environment shared a similar set of core genes and that the species accumulated more specific genes that facilitated resistance to environmental stresses under different environmental conditions. WCO-9 has accumulated a complete set of oil metabolism genes under a long-term oil-contamination environment, and the compact arrangement of abundant lipase and lipase chaperones has further strengthened the ability of the strain to survive in such environments. This is the main reason why WCO-9 is able to degrade oil significantly more effectively than ATCC 17908. In addition, WCO-9 possesses a specific lipase that is not found in homologous strains. In summary, A. junii WCO-9, with a complete triglyceride degradation pathway and the specific lipase gene, has great potential in environmental remediation and lipase for industry.

The effect of biodiesel production method on its combustion behavior in an agricultural tractor engine.

In this study, biodiesel fuel was produced from waste cooking oil (WCO) using a heterogeneous catalyst under microwave (MB) and conventional (CB) heating, and fueled in an agricultural tractor engine to evaluate the engine performance as well as emissions. The biodiesels presented different fatty acid methyl ester (FAME) profiles where MB had lower unsaturated FAME chains. Beyond the transesterification reaction time, the energy consumed for MB biodiesel production diminished by around eight times compared to that required for CB production. The engine results confirmed the positive influence of blending net diesel fuel with biodiesel for enhancing the engine performance and reducing the emissions. More than 20% increment in the engine power and torque was detected at all engine loads (the engine speed was adjusted at 1500 rpm). The hydrocarbon (HC), carbon monoxide (CO), and smoke opacity (SO) indicated significant reductions compared to when net diesel fuel was used. According to statistical analysis, CB25 and MB25 fuels presented a suitable combination as fuel where MB25 provided better engine performance, lower HC and SO emissions, with CO emissions reaching the minimum amount by CB fuels.

Critical review on waste cooking oil rejuvenation in asphalt mixture with high recycled asphalt.

Waste cooking oil (WCO) as a rejuvenator is gaining attention in the pavement industry to incorporate higher reclaimed asphalt (RA) in asphalt mixture. This review article provides a comprehensive review on the current state and the feasibility of turning WCO and RA into cleaner and sustainable asphalt pavement material. Considering the advancements in research related to the utilization of WCO in RA mixture, it was necessary to critically review the past and recent studies to provide a methodological scope for future research. The review discusses a plethora of characteristics focusing on chemical, rheological, simulation, environmental, and economical findings related to the utilization of WCO in RA mixtures. Based on the review, WCO can be adjudged as a potential material to rejuvenate asphalt mixtures with higher recycled asphalt content. Furthermore, although WCO enhances low-to-intermediate temperature performance, studies indicated that moisture damage and higher temperature properties are compromised. Future research scope exists in understanding the rejuvenation capabilities of different WCOs and blends of different types of WCO, optimizing the transesterification process of WCO to improve its quality, molecular dynamic simulations focusing on transesterified WCO, quantification of environmental and economic benefits of recycled asphalt mixtures with WCO, and field performance studies.

Experimental Investigation of Eco-Friendly Anhydrous Calcium Sulfate Whisker and Waste Cooking Oil Compound Modified Asphalt Mixture.

In recent years, waste material recycling and reuse have attracted great interest as environmentally friendly modifiers to improve asphalt pavement performance. In this study, anhydrous calcium sulfate whiskers (ACSW), synthesized using phosphogypsum waste, and waste cooking oil (WCO), one of the most prevalent waste oils, were used together as modifiers to create an environmentally friendly asphalt mixture. In particular, WCO was used to compensate for the negative effects of ACSW on asphalt mixture performance at low temperatures. A variety of ACSW and WCO compound-modified asphalt mixtures were fabricated. High-temperature stability, medium-temperature fatigue, low-temperature anti-cracking, moisture susceptibility, repeated freeze-thaw, and long-term aging tests were conducted to comprehensively evaluate the pavement performance. Compared to the base asphalt mixture, the compound-modified asphalt mixtures were demonstrated to have better high- and low-temperature, moisture susceptibility, fatigue, anti-freezing, and anti-aging properties, especially for the 6%ACSW and 2%WCO compound-modified asphalt mixture. Therefore, the 6%ACSW and 2%WCO compound-modified asphalt mixture was ultimately selected for use in construction, as this mixture can meet the requirements for regions with cold winters and hot summers.

Optimization of Continuous FAME Production in High-Performance Bumpy Surface Rotor Reactor under Theoretical Molar Ratio by Response Surface Methodology.

The continuous production of fatty acid methyl ester (FAME) from waste cooking oil (WCO) via transesterification was carried out under theoretical methanol to oil molar ratio using a high-performance bumpy surface rotor reactor (BSRR). Three types of rotors with different area fractions (AF) of 6.9%, 13.8% and 27.6% were used to equip the BSRR. The selection of the highest performance rotor was compared by factorial experiments. Absolute methanol with 99.9 vol% purity was used as the reactant and potassium hydroxide with 90 wt% purity was used as the base catalyst. Response surface methodology (RSM) was applied to design the experiments and predict the optimal conditions. The three variables in RSM were 0.58-1.43 wt% potassium hydroxide concentration [KOH], 2160-3840 rpm rotor speed, and 1.38-4.74 L/min flow rate. The performance was the specific energy consumption (SEC). The highest performance rotor was AF27.6%. In the first step, the transesterification process was performed using [KOH] 1.5 wt%, a rotor speed of 3000 rpm and a flow rate of 2.027 L/min to produce 98.6 wt% FAME and using SEC at 12.5 W h/kg. In the second step, RSM predicted the optimal condition of [KOH] 1.016 wt%, rotor speed 2910 rpm, flow rate 2.134 L/min and FAME content 97.3 wt%. The actual FAME content averaged 97.16 wt%. The biodiesel properties complied with the EN 14214 standard. This biodiesel production can reduce the cost of methanol by one-half and the cost of KOH by one-third. The energy consumption is only 0.012 kW・h/kg, so the methanol recovery process is not necessary. It has low KOH residue, so washing with water is superfluous and uses minimal energy, which can reduce a lot of costs. The high flow rate of 128 L/h can be used to scale up commercial production.

Meta-analyses of molecular seafood studies identify the global distribution of legal and illegal trade in CITES-regulated European eels.

Authentication of seafood products by means of molecular techniques has relevance for food sustainability and security, as well as international trade regulation, linked to transparency in food manufacturing. We focus on the molecular detection of the depleted European eel Anguilla anguilla, a species for which strict international trade regulations are in place since 2010, in studies conducted outside Europe. We found thirteen studies from nine countries (Canada, China, Japan, Malaysia, Peru, Singapore, South Korea, Taiwan, and USA) for which, on average, 59 ± 28% of the 330 sequenced eel samples comprised European eel. Only China, Japan, South Korea, and USA reported the import of European eel in the years prior to sampling. The authentication of eel products demonstrates a global, in part illegal, trade in European eel, covered up by incomplete or fraudulent labelling. This calls into question the compliance with existing national and international trade regulations and its implications for food safety and sustainability.

Performance, combustion and emission characteristics of variable compression ratio engine using waste cooking oil biodiesel with added nanoparticles and diesel blends.

The present experimental work is carried out to analyse the performance, combustion, and exhaust emission characteristics of variable compression ratio (VCR) diesel engine using blended biofuel (B20) with nanoadditives. Transesterified biodiesel was prepared from waste cooking oil (WCO). The cerium oxide nanoparticles (CERIA) were produced and categorized by precipitation technique, SEM and XRD analysis. These nanoadditives mixed with biofuel blend by magnetic stirrer and then by ultrasonication. The test procedure was carried out under the following fuel blends: 20% of biodiesel added to 80% diesel (B20), 15ppm, 30ppm, 45ppm, 60ppm and 75ppm cerium oxide nanoparticles added with B20 blend (diesel, B20, B20+CERIA15, B20+CERIA30, B20+CERIA45, B20+CERIA60, B20+CERIA75). The engine was operated at fixed compression ratio 20:1 and constant speed at various load conditions 0%, 25%, 50%, 75% and 100%, and results were compared to diesel at 100% load. The improvement in B20 fuel characteristics was observed by adding cerium oxide nanoparticles. The outcomes indicate better improvement in the blended sample of B20+CERIA45 ppm with brake thermal efficiency increased by 3.62% and specific fuel consumption decreased by 3.3% than the neat diesel. Presence of added particles gives better atomization which prompts total burning in the combustion chamber and builds up the amplified pressure data. The emission of CO and HC outflow dimnishes by the addition of CERIA nanoparticles in blended biofuel. Additionally, there is a reduction in NOx by expanding the CERIA dosage in the fuel mixer. This occurs due to CERIA particles presented in a fuel blend behaving as an oxygen buffer and engaging the O2 for decreasing the NOx formation.

Dual radicals-enhanced wet chemical oxidation of non-biodegradable chemicals.

Total organic carbon (TOC) has been suggested and utilized as an index of organic matter in aqueous phases. The overall performance of TOC is highly dependent on the method of oxidation of organic matter to carbon dioxide, such as high-temperature combustion (HTC) and wet chemical oxidation (WCO). HTC requires more energy and maintenance cost, it is a major barrier to the field application. In contrast, WCO is more suitable for the application of on-line monitoring systems due to requiring lower energy and easy maintenance. However, WCO shows lower oxidation than HTC, thus, oxidation performance should be improved for the application to the field. In this study, a dual radical system (DRS), including sulfate and hydroxyl radicals, was proposed to enhance oxidation ability. The DRS uses alkaline pH and persulfate to generate sulfate radicals, which have been used to activate hydroxyl radicals and oxidize organic matter. The oxidation mechanism for the DRS has been verified using model chemicals with different reaction rate constants. The applicability of the DRS has been confirmed using authentic wastewater with a high concentration of chloride. In this study, the DRS showed similar performance compared to the HTC within 10 % error range. The DRS shows similar oxidation performance with HTC even at a high concentration of chloride. DRS did not show interference by the presence of chloride up to 30,000 mg/L of chloride. Results of this study indicate that the DRS can enhance overall oxidation performance compared to the conventional WCO system.

Eco-friendly biosurfactant from Wickerhamomyces anomalus CCMA 0358 as larvicidal and antimicrobial.

Kitchen waste oil (KWO) was evaluated as a substrate for production of biosurfactant by Wickerhamomyces anomalus CCMA 0358 and was tested against Aedes aegypti larvae, the mosquito causing neglected diseases, such as dengue fever, Zika, and Chikungunya, achieving 100 % mortality in the lowest concentration (6.25 %) evaluated in 24 h. Furthermore, possible applications of this compound were evaluated as antibacterial, antiadhesive, and antifungal. At a concentration of 50 %, the biosurfactant was found to inhibit the growth of Bacillus cereus, showing high inhibitions levels against Salmonella Enteritidis, Staphylococcus aureus, and Escherichia coli. The antifungal activity was evaluated against Aspergillus, Cercospora, Colletotrichum, and Fusarium, obtaining results of up to 95 % inhibition. In addition to these promising results, the yeast W. anomalus produced the biosurfactant from an inexpensive substrate, which increases the possibility of its application in several industries owing to the low cost involved.

The impact of low to high waste cooking oil-based biodiesel blends on toxic organic pollutant emissions from heavy-duty diesel engines.

As yet, the effect of biodiesels on the emissions of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from heavy-duty diesel engines (HDDEs) has only been studied using limited fuel blend ratios. To clarify the influence of using higher fractions of biodiesel on the emissions of toxic organic pollutants from diesel engines, in this research, the emissions of PM, PAHs, and persistent organic pollutants (POPs) from EURO IV and EURO III HDDEs fueled by low to high waste cooking oil (WCO)-based biodiesel-petrodiesel fuel blends were studied, including D100 (0% biodiesel), B20 (20%), B40 (40%), B60 (60%), B80 (80%), and B100 (100%). The engines were tested according to the US FTP-75 test procedure. The results for the EURO IV diesel engine showed that the PM and toxic organic pollutant emissions were reduced with increases in the blending ratio up until the B60 scenario when compared to the D100 scenario. This is because biodiesel has higher oxygen content and no or lower aromatic content than petrodiesel. Nevertheless, during the B80 and B100 scenarios, the PM and toxic organic pollutant emissions increased due to the high viscosity property of biodiesel, which negatively affected the combustion process. The biodiesel effect on the emissions from EURO III engine was more pronounced because of its lower combustion efficiency, and therefore the improvement in combustion using biodiesel resulted in greater PCDD/F reductions.