Amount Of Ethanol Research Articles

Reactive Oxygen Species Are Central Mediators of Vascular Dysfunction and Hypertension Induced by Ethanol Consumption.

Consumption of high amounts of ethanol is a risk factor for development of cardiovascular diseases such as arterial hypertension. The hypertensive state induced by ethanol is a complex multi-factorial event, and oxidative stress is a pathophysiological hallmark of vascular dysfunction associated with ethanol consumption. Increasing levels of reactive oxygen species (ROS) in the vasculature trigger important processes underlying vascular injury, including accumulation of intracellular Ca2+ ions, reduced bioavailability of nitric oxide (NO), activation of mitogen-activated protein kinases (MAPKs), endothelial dysfunction, and loss of the anticontractile effect of perivascular adipose tissue (PVAT). The enzyme nicotinamide adenine dinucleotide phosphate (NADPH) oxidase plays a central role in vascular ROS generation in response to ethanol. Activation of the renin-angiotensin-aldosterone system (RAAS) is an upstream mechanism which contributes to NADPH oxidase stimulation, overproduction of ROS, and vascular dysfunction. This review discusses the mechanisms of vascular dysfunction induced by ethanol, detailing the contribution of ROS to these processes. Data examining the association between neuroendocrine changes and vascular oxidative stress induced by ethanol are also reviewed and discussed. These issues are of paramount interest to public health as ethanol contributes to blood pressure elevation in the general population, and it is linked to cardiovascular conditions and diseases.

Boosting CO2 Conversion by Synergy of Lead-Free Perovskite Cs2SnCl6 and Plasma with H2O.

Although dielectric barrier discharge (DBD) plasma is a promising technique for CO2 conversion, realizing CO2-to-alcohol is still challenging via the use of H2O. Herein, for the first time, efficient CO2 conversion was achieved via the synergism between the Cs2SnCl6 photocatalyst and DBD plasma assisted by H2O. The CO2 conversion ratio of plasma photocatalysis was 6.5% higher than that of only the plasma and photocatalysis, implying that the synergism of plasma catalysis and photocatalysis was achieved. Furthermore, the DBD plasma assisted by the Cs2SnCl6 photocatalyst could convert CO2 and H2O to CO and a small amount of methanol and ethanol. The CO2 conversion ratio was enhanced by 50.6% in the presence of H2O, which was attributed to the improvement of charge transfer due to the increased electrical conductivity of the photocatalyst surface during plasma discharge. This work provides a new idea for developing an efficient system for CO2 utilization.

Identification of volatile organic compounds as markers to detect Monilinia fructicola infection in fresh peaches

Monilinia spp. are among the main fungal pathogen affecting peaches, and they can cause severe pre- and postharvest losses. Development of smart packaging technologies (e.g., volatile indicators), facilitating infection detection and preventing other fruit from being contaminated, is still limited. In this study, we compared for the first time the aroma profile of whole healthy fresh peaches to Monilinia fructicola-artificially inoculated peaches, identifying discriminant volatile organic compounds (VOCs). More than one hundred VOCs were detected by applying head space solid-phase microextraction followed by GC-MS analysis. The level of methyl esters, hydrocarbons, lactones, and acids decreased in infected peaches indicating fruit aroma deterioration, while the concentration of ethyl esters and alcohols increased. In particular, the amount of ethanol and derived ethyl acetate reached a maximum of 24- and 20-fold increase in the infected peaches, respectively. Isobutanol, propyl acetate, and ethyl isovalerate were specifically emitted by M. fructicola-infected peaches. These compounds might serve as markers for the development of smart sensors allowing the detection of fungal infection.

Morphology Controlled Deposition of Vanadium Oxide (VOx) Nanoparticles on the Surface of Highly Reduced Graphene Oxide for the Photocatalytic Degradation of Hazardous Organic Dyes.

Semiconducting nanomaterials based heterogeneous photocatalysis represent a low-cost, versatile technique for environmental remediation, including pollution mitigation, energy management and other environmental aspects. Herein, we demonstrate the syntheses of various heterogeneous photocatalysts based on highly reduced graphene oxide (HRG) and vanadium oxide (VOx)-based nanocomposites (HRG-VOx). Different shapes (rod, sheet and urchin forms) of VOx nanoparticles were successfully fabricated on the surface of HRG under solvo-/hydrothermal conditions by varying the amount of water and ethanol. The high concentration of water in the mixture resulted in the formation of rod-shaped VOx nanoparticles, whereas increasing the amount of ethanol led to the production of VOx sheets. The solvothermal condition using pure ethanol as solvent produced VOx nano-urchins on the surface of HRG. The as-prepared hybrid materials were characterized using various spectroscopic and microscopic techniques, including X-ray diffraction, UV-vis, FTIR, SEM and TEM analyses. The photocatalytic activities of different HRG-VOx nanocomposites were investigated for the photodegradation of methylene blue (MB) and methyl orange (MO). The experimental data revealed that all HRG-VOx composite-based photocatalysts demonstrated excellent performance toward the photocatalytic degradation of the organic dyes. Among all photocatalysts studied, the HRG-VOx nanocomposite consisting of urchin-shaped VOx nanoparticles (HRG-VOx-U) demonstrated superior photocatalytic properties towards the degradation of dyes.

The effect of ultrasound process on lactic acid bacteria, physicochemical and sensory properties of yoghurt, before and after inoculation of starter cultures into milk

The effect of ultrasound (US) applied before (US + i) and after (i + US) inoculation of yoghurt starter into cows' milk on some parameters of yoghurt was investigated. Lightness (L*) values, amounts of acetaldehyde, diacetyl, acetoin, ethanol, lactic, pyruvic, and acetic acid were higher in the US‐treated groups compared with control (P < 0.05). In the US + i group, the total amount of ketones increased. Lactobacillus and Streptococcus spp. numbers reached log ≥7.0 cfu/g in all groups (P > 0.05). It can be concluded that low‐intensity ultrasound applied to cows' milk before or after inoculation of yoghurt starters increases the aroma components and organic acid content of yoghurt.

Co‐production of biobutanol and biomethane from distillers' grain waste by an integrated process

AbstractBackgroundDistillers' grain waste (DGW) is the main by‐product in the Baijiu‐making process and its management remains a great challenge for the Baijiu industry. To address this issue, an integrated biobutanol and biomethane production process was established to obtain valuable products from DGW and reduce environmental pollution.ResultsIn the integrated process, DGW was hydrolyzed and detoxified to produce biobutanol, while the distillery waste derived from solvent extraction process was used for biomethane fermentation. After the optimization of overliming detoxification of DGW hydrolysate by artificial neural network and genetic algorithm, totals of 10.65 ± 0.07 g L−1 butanol and 4.51 ± 0.21 g L−1 isopropanol were attained with negligible amounts of acetone and ethanol (i.e. 0.14 ± 0.00 and 0.52 ± 0.06 g L−1, respectively). Anaerobic digestion of the distillery waste was efficient, and the chemical oxygen demand removal rate approached 92.3 ± 0.1% with a methane yield of 167.8 ± 1.2 mL g−1 TCODremoved. Moreover, the anaerobic digestion effluent could be recycled as a potential substitute for process water in biobutanol fermentation without having any negative effect on enzymatic hydrolysis of DGW, and the butanol production also reached 8.19 ± 0.29 g L−1.ConclusionThe present study provides a new idea for comprehensive utilization of DGW towards energy and resource recovery, without secondary pollution. © 2023 Society of Chemical Industry.

Mathematical modeling of ethanol distribution in body fluids

The aim of the study is to build a kinetic model of ethanol distribution in biological body fluids, as well as its implementation in the format of computer programs. Analytical mathematical modeling of ethanol kinetics in body fluids after single and multiple oral alcohol intake was performed. An equation for the distribution of ethanol in internal media and other body fluids has been developed based on a kinetic model of zero-order elimination with absorption and irrevocable absorption deficiency, as well as achieving an equilibrium state with first-order blood plasma. On the basis of this kinetic model, computational algorithms are constructed for estimating the concentration of ethanol in body fluids at a given time, the peak concentration of ethanol and the time of its achievement, the time of complete removal of ethanol, the beginning and end of the false elimination period. Solutions to the problem of determining the amount of ethanol taken by its concentration in the biological fluid and the level of etholemia at this point in time with the possibility of calculating their maximum absolute errors are obtained. The constructed kinetic model is generalized to any number of ethanol receptions separated by time intervals of any duration. The developed computational algorithms are implemented in the format of the computer programs 'Alcohol Calculator V 7.0" and "Alcohol Calculator V 6.0", which are recommended for use in the forensic medical expert assessment of acute alcohol intoxication.

Solvent-Controlled Morphology of Zinc-Cobalt Bimetallic Sulfides for Supercapacitors.

Bimetallic sulfides offer high theoretical specific capacitance and good stability as electrode materials due to their diverse redox reactions, larger specific surface areas, and better conductivity. The morphology of the electrode material is an important influencing factor for the electrochemical properties. Herein, a series of ZnCoS electrode materials with different morphologies were prepared by varying the solvent in the solvothermal reaction, and the effects of different microstructures on the electrochemical properties of ZnCoS were investigated. The ratio of water and ethanol in the solvent was controlled to modulate the microstructure of the as-prepared ZnCoS materials. XRD and XPS revealed the physical and chemical structure of the ZnCoS materials. SEM and TEM observations showed that the microstructure of ZnCoS transformed from one-dimensional wires to two-dimensional sheets with increasing amounts of ethanol. The maximum specific capacitance of the as-prepared ZnCoS materials is 6.22 F cm-2 at a current density of 5 mA cm-2, which is superior to that of most previously reported bimetallic sulfides. The enhanced electrochemical performance could be ascribed to its sheet-assembled spherical structure, which not only shortens the path of ion diffusion but also increases the contact between surface active sites and the electrolyte. Moreover, the spherical structure provides numerous void spaces for buffering the volume expansion and penetration of the electrolyte, which would be favorable for electrochemical reactions. Furthermore, the ZnCoS electrodes were coupled with activated carbon (AC) electrodes to build asymmetric supercapacitors (ASCs). The ASC device exhibits a maximum energy density of 0.124 mWh cm-2 under a power density of 2.1 mW cm-2. Moreover, even under a high-power density of 21 mW cm-2, the energy density can still reach 0.055 mWh cm-2.

Impact of two different rodent diets on maternal ethanol consumption, serum ethanol concentration and pregnancy outcome measures.

Recent studies report varying levels of ethanol consumption by rodents maintained on different commercially available laboratory diets. As varied ethanol consumption by dams may impact offspring outcome measures in prenatal ethanol exposure paradigms, we compared ethanol consumption by rats maintained on the Envigo 2920 diet, used in our vivarium, with an isocalorically equivalent PicoLab 5L0D diet used in some alcohol consumption studies. Compared to 5L0D diet, female rats maintained on 2920 diet consumed 14% less ethanol during daily 4-h drinking sessions prior to pregnancy and 28% less ethanol during gestation. Rat dams consuming 5L0D diet gained significantly less weight during pregnancy. However, their pup birth weights were significantly higher. A subsequent study revealed that hourly ethanol consumption was not different between diets during the first 2h, but was significantly lower on 2920 diet at the end of the third and fourth hours. The mean serum ethanol concentration in 5L0D dams after the first 2h of drinking was 46mg/dL compared to 25mg/dL in 2920dams. Further, ethanol consumption at the 2-h blood sampling time point was more variable in 2920dams compared to 5L0D dams. An invitro analysis mixing each powdered diet with 5% ethanol in acidified saline revealed that a 2920 diet suspension adsorbed more aqueous medium than the 5L0D diet suspension. The total ethanol remaining in aqueous supernatant of 5L0D mixtures was nearly twice the amount of ethanol in supernatants of the 2920 mixtures. These results suggest that the 2920 diet expands to a greater extent in aqueous medium than the 5L0D diet. We speculate that increasing adsorption of water and ethanol by the 2920 diet may reduce or delay the amount of ethanol absorbed and may decrease serum ethanol concentration to a greater extent than would be predicted from the amount of ethanol consumed.

Ethanol-paired conditioned stimulus effects on concurrent reinforced responding for ethanol and food.

The influence of Pavlovian Conditioned Stimuli (CS) on ethanol self-administration and choice between ethanol and an alternative are potentially important. Ethanol-paired CS might increase ethanol self-administration, especially when it has been reduced during recovery, though the selectivity of these increases has been questioned. To date, one study examined the effects of an ethanol-paired CS on ethanol choice and found that the CS increased ethanol-responding more than food-responding when both were in extinction. However, it remains unclear whether ethanol-paired CS increase ethanol-choice that is not in extinction. Here, we examine the effects of an ethanol-paired CS on ethanol-choice when both food- and ethanol-responding are reinforced. Sixteen adult male Lewis rats were trained on a concurrent schedule to respond for ethanol on one lever and for food on the other lever. Ethanol was available under an FR 5 schedule, and food was available under an FR schedule that was adjusted for each rat to earn an equal number of food and ethanol deliveries. Then, 2-min light presentations were paired with an RT 25-sec schedule of ethanol delivery for 10 sessions in the absence of both levers. After this, subjects were placed back on the concurrent schedule for one session, then five sessions with the CS being present or absent on each trial of the concurrent schedule occurred. Rats learned to respond on one lever for ethanol and on the other for food and earned similar numbers of ethanol and food deliveries. During Pavlovian Conditioning, the number of head entries into the head-entry detector was higher in the presence of the CS than in its absence. In the test sessions, rats made more ethanol responses in the presence of the CS than in its absence. However, this effect was small and did not increase the amount of ethanol earned. Thus, ethanol-paired CS could increase ethanol-responding under a choice procedure but did not increase ethanol consumption meaningfully under the studied conditions.

In Vitro Hypoxic Environment Enhances Volatile Compound Production in Persian Violet Flowers

Flowers of Persian violet (Exacum affine Balf. f. ex Regel) that are grown in nature typically produce a scent. However, whether Persian violet flowers developed inside sterile containers produce odors has yet to be studied. Therefore, this research aimed to study and compare the effects of ex vitro and in vitro environments on the volatile composition of Persian violet flowers. Persian violet flowers obtained from an in vitro culture and potted plants were analyzed for volatile constituents using gas chromatography–mass spectrometry (GC-MS). The main constituent of the volatile compounds in the Persian violet flowers grown in both conditions was alcohol, with 3-hexen-1-ol, which produces a grassy-green odor, being the dominant substance. In addition, the in vitro Persian violet flowers contained the highest amount of ethanol, which produces a wine aroma—followed by the terpene alcohol β-citronellol, which produces a rose scent. However, 3-carene (citrus odor), caryophyllene (floral odor), humulene (woody odor), and β-ionone (floral odor) were detected only in Persian violet flowers grown in natural conditions. Therefore, these results indicate that hypoxia possibly occurred during plantlet growth in the in vitro environment and caused some different volatile compound production from that in natural conditions.

Emission Characterization of Petrol, Ethanol and Spent Engine Oil Blends for Two-Stroke Spark Ignition Engine

Exhaust emission has remained a big global concern in atmospheric change, and has thus, lead to stiffer polices on emission. To achieve the set emission targets different fuel mix and combustion process are continuously been investigated. This work is used to practically model the condition of a two-stroke engine that has run over time whose used lubricating oil finds its way from the sump to the combustion chamber and thus resulting to greater rate of incomplete combustion and higher emission. An exhaust analyser with a deep probe was deployed to access the out-going burnt gasses from a two-stroke spark ignition engine that is fed with multi blends of petrol, ethanol and spent engine oil. The characteristics of the emission constituents were investigated and compared to the global limits set by different organizations such as California Air Resources Board, Environmental Protection Agency in USA, International Council on Clean Transportation, Road Transport Bureau- in Japan, and European Emission Standard Agency, among others. The result shows an increase in , and emissions with samples that contain spent oil as against those with new engine oil which is also more effective. It was also found that samples with higher quantity of ethanol show lower emission of , and gases. This is likely due to interstation of ethanol molecules with that of the spent oil, thus making it more potent for further combustion. This was also supported with the fact that emission was higher in blends with higher quantity of ethanol. Thus, the presence of ethanol in fuel blend used in two-stroke spark ignition engine may be considered to be a source of improvement in combustion and hence a means of reducing emission in two-stroke port operated spark ignition engines.

Evaluation of Kluyveromyces spp. for conversion of lactose in different types of whey from dairy processing waste into ethanol.

The processing of dairy products currently generates significant amounts of waste, particularly in the form of liquid whey. The disposal of whey poses a challenge to the environment due to its high organic content and biological oxygen demand. Whey contains lactose, soluble proteins, lipids, and minerals. While Saccharomyces cerevisiae can efficiently utilize glucose, they are unable to metabolize lactose. In contrast, Kluyveromyces spp. encode two genes, Lac12 and Lac4 that enable conversion of lactose to other by-products such as ethanol. Here, we selected five Kluyveromyces yeast inoculated into three different types of whey substrates, cheddar sweet whey, cream cheese acid whey, and yogurt acid whey that could be used to convert lactose into ethanol. We demonstrate that differences exist in ethanol production across different whey substrates inoculated with Kluyveromyces yeast. In sweet whey, K. lactis, K. lactis Y-1205 and K. lactis Y-1564 were the highest ethanol producing strains. The highest amount of ethanol produced was 24.85 ± 3.5 g/L achieved by Y-1564 in sweet whey (96.8% efficiency). K. lactis Y-1205 produced 22.39 ± 5.6 g/L ethanol in yogurt acid whey. In cream cheese acid whey, K. lactis strains produced significantly higher ethanol levels compared to S. cerevisiae and K. marxianus (p < 0.05). Outcomes from this study could provide a simple and cheap solution for small-to medium-sized dairy processing facilities to ferment lactose in whey into ethanol using lactose-consuming yeasts.

Evaluation of detailed combustion, energy and exergy analysis on ethanol-gasoline and methanol-gasoline blends of a spark ignition engine

This study discusses the combustion behaviour of an SI engine and evaluates the engine's thermodynamic performance through energy and exergy analysis. The test results compared the fuels obtained by adding small amounts of ethanol (and equal amounts of methanol) to gasoline with each other and with gasoline as the reference fuel. The study was conducted at a constant engine speed and five different engine loads (2, 2.5, 3, 3.5, and 4 Nm). Upon examining the study results, it was observed that the addition of ethanol and methanol to gasoline increased the maximum in-cylinder pressure. While the gasoline-alcohol mixtures relatively reduced the average in-cylinder gas temperature, the pressure increase rates significantly increased. It was observed that the volumetric addition of ethanol/methanol to gasoline had a relatively decreasing effect on thermal and exergetic efficiency values.

Utilization of Festuca arundinacea Schreb. Biomass with Different Salt Contents for Bioethanol and Biocomposite Production

Soil salinity is one of the particularly important environmental factors, which limits the growth and development of plants, reduces the amount of crops and causes serious economic damage. The study found that Festuca arundinacea can be successfully used for the management and bioremediation of saline habitats, and it is characterized by a very well-developed root system and an average high biomass production of approx. 14.8 Mg∙ha−1, which can be used for industrial applications. Tall fescue biomass from soils with different levels of salinity was used to obtain bioethanol using 1.5% NaOH pretreatment and for the process of simultaneous enzymatic hydrolysis and ethanol fermentation (SSF). It was found that the content of Na+ ions in the tall fescue biomass had no significant effect on the amount of ethanol obtained (the average 19.32 g∙100 g−1 of raw material). F. arundinacea biomass was also used as a natural filler to obtain green composites using a biodegradable polylactide (PLA) matrix. It has been shown that tall fescue biomass with the lowest sodium content in biomass (approx. 2.5 mg∙g−1) from an area with high saline (above 6 g NaCl∙L−1) has the smallest effect on reducing the tensile and flexural strength of composites. Moreover, the highest value of bioethanol concentration (21.2 g∙100 g−1 of raw material) for this biomass sample was obtained.

Molecular Insight into the Effects of Clustering on the Dynamics of Ionomers in Solutions.

Ionizable groups tethered to polymers enable their many current and potential applications. However, these functionalities drive the formation of physical networks through clustering of the ionic groups, resulting in constrained dynamics of the macromolecules. Understanding the molecular origin of this hindrance remains a critical fundamental question, whose solution will directly impact the processing of ionizable polymers from molecules to viable materials. Here, using quasielastic neutron scattering accompanied by molecular dynamics simulations, segmental dynamics of slightly sulfonated polystyrene is studied in solutions as the cohesion of the ionic assemblies is tuned. We find that in cyclohexane the ionic assemblies act as centers of confinement, affecting dynamics both on macroscopic lengths and in the vicinity of the ionic assemblies. Addition of a small amount of ethanol affects the packing of the ionizable groups within the assemblies, which in turn enhances the chain dynamics.

18F]Fluoromisonidazole synthesis method: development and optimization by cartridge purification

Abstract [18F]Fluoromisonidazole ([18F]FMISO) as nitroimidazole derivative with 18F radioisotope is a widely known and studied hypoxia marker for PET imaging. A number of automated synthesis modules and purification strategies for production of [18F]FMISO have been described in recent years. The goal of this work was to develop [18F]FMISO synthesis process with Synthera module with solid phase extraction (SPE) Sep-Pak purification cartridges. To adjust the reaction conditions we synthesized [18F]FMISO under different reaction conditions and using various reversed-phase (RP) purification cartridges (HLB light, HLB plus, tC18, C18 environmental, Chromafix PS-RP). The synthesis was performed by nucleophilic substitution of commercial 1-(2′-nitro-1′-imidazolyl)-2-O-tetrahydropyranyl-3-O-toluenesulfonylpropanediol precursor and subsequent acidic hydrolysis. Further, the product mixture was purified by passing through the SPE cartridge. The produced [18F]FMISO was retained on the cartridge, while the impurities passed through the cartridge into a waste. The retained [18F]FMISO was then eluted with small amounts of ethanol in water and eluates were collected in the final product vial. The product sample was subjected to quality control tests, while for waste sample chemical and radiochemical tests were performed. We have developed an efficient synthesis method of [18F]FMISO with cartridge purification with good radiochemical yield (RCY) and high chemical and radiochemical purity in accordance with the Ph. Eur. Monograph for Fluoromisonidazole (18F) injection.

Green recovery optimization of phenolic compounds from “Spinoso sardo” globe artichoke by-products using response surface methodology

The reuse and valorization of agri-food by-products is a pivotal activity in the pursuit of a circular model that can improve sustainability and efficiency of agri-food production. During artichoke processing, 60–80% of the biomass produced by the plant consists of inedible fractions, which nevertheless represent a natural source of high value-added compounds, such as phenolics. In this study, response surface methodology was applied to investigate and optimize the amount of ethanol and the reduction of extraction time to achieve the maximum yield of polyphenols and flavonoids from artichoke stems, leaves, and bracts, by using two extraction methods, namely maceration and ultrasound-assisted extraction. Overall, phenolic compounds were most concentrated in extracts obtained from the stems, followed by those derived from the bracts and leaves, with the percentage of ethanol being the most influential factor. After applying the optimization criteria, the best factor setting to achieve maximum extraction yields and strong antioxidant capacities was: 53% ethanol for stems, 45% for leaves, and 50% for bracts and 60 min for all by-products in the case of maceration; 10 min for stems and leaves with 42 and 20% of ethanol, respectively, and 41 min and 64% ethanol for bracts in the case of ultrasound-assisted extraction. Comparison between the two techniques evidenced that maceration was significantly more efficient, but similar recoveries were obtained with ultrasound-assisted extraction in shorter extraction time and lower ethanol consumption. Therefore, using this unconventional method to convert Spinoso Sardo artichoke by-products into bioactive ingredients with interesting industrial applications could be a viable strategy to reduce food losses and mitigate related environmental impacts.

Experimental investigation of ethanol diesel dual fuel DI diesel engine

This paper investigates the combustion and performance characteristics of an ethanol – diesel dual fuel direct injection diesel engine. An air-cooled constant speed single cylinder diesel engine was operated with dual fuel mode in which ethanol was injected in the inlet manifold and diesel was injected inside the cylinder. An electronic fuel injection system operated by LabView software was used to inject the ethanol. Virtual instrumentation principle was used to generate output pulses for triggering ethanol injection. Diesel fuel was injected by conventional mechanical fuel injection system. The engine was loaded by an eddy current dynamometer. A piezoelectric pressure pickup with charge amplifier connected to PC based data acquistion system recorded cylinder pressure data at every crank angle interval. A crank angle degree marker measures the crank angle position for every crank angle. Tests were conducted on the engine in diesel and ethanol – diesel dual fuel mode. The cylinder pressure traces were used to calculate the heat release rates and combustion parameters. Optimum ethanol quantity was injected at every operating point. An AVL five-gas analyzer was used to measure the different exhaust pollutants. The smoke emission was measured by an AVL smoke meter in Hatridge equivalent percentage. Experimental results show that 40% of diesel can be replaced by ethanol at full load and there was 5.5% reduction in specific energy consumption. Also it was found that 32% reduction in smoke level (Opacity) and 25% reduction in NOx emissions at full load operating condition. It was also observed that the engine was running smoothly without knocking.

Optimization of Fermentation for Bioethanol Production from sour Citrus aurantifolia Fruit Juice using Natural Palmyrah Toddy Yeast

&#x0D; Large scale consumption of fossil fuel to meet the increasing demand causes adverse effects on the environment due to the emission of harmful greenhouse gases. The production of bioethanol from diverse fruit juices that are underutilized because of poor taste quality could be one of the alternative fuels to overcome the issues. The objective of the study was to produce bioethanol from sour Citrus aurantifolia fruit juice using palmyrah toddy yeast and to optimize the conditions to increase the bioethanol yield. The sour Citrus fruit juice was inoculated with palmyrah toddy yeast (Saccharomyces cerevisiae - 2g/L) in the fermentation media (100ml, sour Citrus fruit juice: distilled water = 1:3) composed of 10 g/L yeast extract, 10 g/L KH2PO4, 2 g/L (NH4)2SO4, 2 g/L peptone and 0.5 g/L MgSO4·7H2O and allowed for fermentation for 24 hours at room temperature. The amount of ethanol produced from the Citrus juice was 0.8% (V/V) after 24 hours of fermentation. In order to optimize the fermentation process for Citrus aurantifolia, a variety of experimental parameters were studied, including the type of nitrogen source (ammonium sulphate, ammonium nitrate, ammonium chloride, and urea), inoculum size (0.4 to 1.0 g/100 mL), temperature (20 to 40 °C), rotation speed (50 to 250 rpm), concentration of raw fruit juice (5 to 100%), amount of urea (0.1 to 2.0 g/100 mL), carbon source (glucose, sucrose, maltose, and dextrose), amount of sucrose (1 to 20 g), pH of the medium (3.0 to 8.0), and incubation period (24 to 96 h). After conducting the experiments, it was found that using Citrus aurantifolia at 100% concentration resulted in significantly higher ethanol yields of 11.50%, which was 14.37 times higher than the non-optimized conditions. The highest yield was achieved when the fermentation was carried out at 35 °C for 24 h with an inoculum concentration of 0.5 g/100 mL, a rotation speed of 150 rpm, a pH of 4.0, 0.1 g/100 mL urea as the nitrogen source, and 10 g/100 mL sucrose as the carbon source. Large scale fermentation study using bioreactor should be done to determine whether this finding could be commercialized.&#x0D; Key words: Bioethanol, Fermentation, Palmyrah toddy yeast, Citrus fruit juice, Urea