Methyl Myristate Research Articles

Biodiesel Production From Waste Cooking Oil Using Catalyst CaO Derived From Strombus canarium shells

In this article, we address the optimal biodiesel production through transesterification reaction using waste cooking oil, methanol and presence of calcium oxide (CaO) as a solid base catalyst. CaO catalyst was activated from calcined Strombus canarium shells, collected at Bangka Belitung Islands Province, Indonesia. X-Ray Diffraction and X-Ray Fluorescence (XRF) were applied to characterize the prepared catalyst. The transesterification process will produce methyl ester (biodiesel) yield of 83.5% was obtained in the optimum condition at the waste cooking oil to methanol molar ratio of 1:12, presence catalyst 3.0% wt relative to oil and temperature reaction of 65 oC for 4 h. The GC-MS analysis assured to identify the chemical composition of the synthesized biodiesel which contained methyl myristate and methyl palmitoleate as the dominant esters. As such, the uses of Strombus canarium shells as a catalyst source and waste cooking oil as a feedstock for biodiesel production.

Choice test to determine potential attractants and repellents for the sheep scab mite, Psoroptes ovis (Acari: Psoroptidae).

A choice test bioassay was devised to screen compounds as potential semiochemicals (e.g., kairomones or allomones that mediate aggregation, attraction or repellence) for the obligate parasitic mite, Psoroptes ovis. The choice test used filter paper discs in a 1:4 test:control ratio and was found to be a reliable, effective and efficient method. Four mammalian lipid components were assessed as potential attractants-linoleic acid, arachidonic acid, methyl myristate and squalene-, and the insect/tick repellent DEET for potential repellence. Linoleic acid was significantly attractive to P. ovis adult females and has the potential to act as an attractant. Identification of P. ovis semiochemicals, especially attractants, would be beneficial in the development of novel control methods and tools for this species. This is essential considering the increase in resistance to the limited prophylactic chemical treatments in the UK, and the high prevalence of scab infections.

Expression profiles and ligand-binding properties of two odorant-binding proteins from Grapholita molesta (Busck) (Lepidoptera: Tortricidae)

Abstract The ligand-binding function of odorant binding proteins (OBPs) that are expressed exclusively or enriched in antennae are well-studied, whilst the ligand binding properties of relatively low expressed OBPs in insect antennae are still unclear. Here, two low expressed GmolOBPs (namely GmolOBP12 and GmolOBP16) were cloned based on the antennal transcriptome of Grapholita molesta, and then their expression profiles and binding properties were investigated via real-time quantitative PCR (qRT-PCR) and fluorescence binding assays, respectively. Multiple sequence alignment and phylogenetic tree analyses displayed that both of GmolOBP12 and GmolOBP16 possessed the typical six-cysteine motifs unique to the classic OBPs subfamily and were classified as such. Although the abundance of transcripts of GmolOBP12 and GmolOBP16 were relatively low compared to that of many other OBPs in the antennal transcriptome of G. molesta, qRT-PCR results indicated that the transcript levels of GmolOBP12 and GmolOBP16 in antennae were significantly higher than those in other tissues. GmolOBP12 displayed higher expression level in male antennae than in female antennae, while the transcript level of GmolOBP16 in antennae was similar for both sexes. Both recombinant GmolOBP12 and GmolOBP16 exhibited strong binding affinities to the sex pheromone (Z)-8-dodecenyl alcohol and host-plant volatile pear ester. Besides, rGmolOBP12 showed outstanding binding affinities to (E)-2-hexenal, benzaldehyde, 1-hexanol, and (Z)-3-hexenyl acetate with Ki values of 4.21, 6.81, 4.68 and 4.68 μM, respectively. rGmolOBP16 had moderate binding abilities with hexanal, decanal, 1-hexanol, methyl myristate and benzonitrile. We speculated that GmolOBP12 may have dual functions in recognition of green leaf volatiles and sex pheromone components and GmolOBP16 may participate in the detection of host-plant volatiles in chemoreception.

Identification of Floral Scent Profiles in Bearded Irises.

Bearded irises are ornamental plants with distinctive floral fragrance grown worldwide. To identify the floral scent profiles, twenty-seven accessions derived from three bearded iris, including Iris. germanica, I. pumila and I. pallida were used to investigate the composition and relative contents of floral scent components by headspace solid-phase microextraction (HS-SPME) and gas chromatography–mass spectrometry (GC-MS). A total of 219 floral scent components were detected in blooming flowers. The scent profile varied significantly among and within the three investigated species. Principal component analysis (PCA) indicated that terpenes, alcohols and esters contributed the most to the floral scent components and 1-caryophyllene, linalool, citronellol, methyl cinnamate, β-cedrene, thujopsene, methyl myristate, linalyl acetate, isosafrole, nerol, geraniol were identified as the major components. In a hierarchical cluster analysis, twenty-seven accessions could be clustered into six different groups, most of which had representative scent components such as linalool, citronellyl acetate, thujopsene, citronellol, methyl cinnamate and 1-caryophyllene. Our findings provide a theoretical reference for floral scent evaluation and breeding of bearded irises.

Extraction and Characterization of Organ Components of the Malaysian Sea Cucumber Holothuria leucospilota Yielded Bioactives Exhibiting Diverse Properties.

The aim of the present study was to extract and characterize bioactive components from separate body organs of Holothuria leucospilota. Preliminary qualitative assessment of the crude extracts was positive for phenols, terpenoids, carbohydrates, flavonoids, saponins, glycosides, cardiac glycosides, steroids, phlobatannins, and tannins in all body organs evaluated. Phenolics were the most abundant group of bioactives accounting for approximately 80%. The extraction solvent mixtures that yielded most compounds evaluated were methanol/acetone (3:1, v:v) and methanol/distilled water (3:1, v:v). In other analyses, GC-MS data revealed diverse metabolic and biologically active compounds, where those in high concentrations included 2-Pentanone, 4-hydroxy-4-methyl- among the ketones; phenol- 2,4-bis(1,1-dimethylethyl)-, a phenol group; and 2-Chlorooctane, a hydrocarbon. Among FA and their methyl/ethyl esters, n-hexadecanoic acid, 5,8,11,14-eicosatetraenoic acid ethyl ester (arachidonic acid), and 5,8,11,14,17-eicosapentaenoic acid methyl ester (EPA) were among the most abundant FAMEs accounting for approximately 50% of the subgroups measured. Data from GC-FID analysis revealed methyl laurate (C12:0), methyl myristate (C14:0), methyl palmitate (C16:0), and methyl stearate (18:0) methyl esters as the most abundant saturated FA, whereas cis-9-oleic methyl ester (C18:1) and methyl linoleate (C18:2) were found as the major monounsaturated FA and PUFA FAMEs, respectively, in the body wall of the species. Taken together, the extraction and characterization of different categories of metabolically and biologically active compounds in various organ extracts of H. leucospilota suggest that the species is potentially a rich source of cholesterol-lowering, antioxidant, antimicrobial, and anticancer agents. These substances are known to benefit human health and assist in disease prevention. These findings justify the use of sea cucumbers in traditional folklore medication and the current interest and attention focused on the species to mine for bioactives in new drugs research.

Synthesis Biodiesel from Waste Cooking Oil with Microwave Irradiation Method as Alternative Renewable Energy Source

Biodiesel is a very potential fuel to replace diesel fuel. WCO can be used as raw material for making biodiesel. One method of making biodiesel is by using microwave irradiation. Microwave heating is more advantageous than conventional method heating, because conventional method heating is very slow and inefficient. This study aims to determine the effect of power, reaction time and physical properties of raw materials in the manufacture of biodiesel from waste cooking oil using microwave irradiation. The experimental stage consists of pretreatment, transesterification, separation, washing, and analysis of biodiesel yields. Transesterification of waste cooking oil takes place in a microwave oven by: (a) variations in microwave power (100, 180, 300, 450, and 600 Watt) at 5 min, and (b) reaction time variation (5, 10, 15, 20 and 25 minutes) at a fixed power of 100 Watt. From the research it is known that the operating conditions to produce the best yield of biodiesel yield on 100 watt microwave power and heating time for 10 minutes. The yield of biodiesel is 93.06%. The laboratory analysis results show five methyl ester compounds (biodiesel) such as methyl myristate, methyl palmitate, methyl linoleate, methyl oleate, and methyl stearate. The physical properties of biodiesel produced have met several criteria of Dirjen Migas no 13483K / 24 / DJM / 2006 for biofuel / biodiesel and SNI 04 - 7182 (2012).

Synthesis of Biodiesel from Low-Quality Crude Palm Oil with Heterogeneous Catalyst Cao-ZnO

Synthetic optimization of methyl ester has been extracted from low-quality crude palm oil using heterogeneous catalyst. Quantitatively, the crude palm oil with low-quality is in abundance. To prepare the raw material to be used for biodiesel, it requires to be refined beforehand. By using heterogeneous catalysts, the synthetic biodiesel would become more affordable and environmentally friendly. This study aimed to synthesize methyl esters from low-quality crude palm oil using CaO-ZnO catalyst and determine its potential as biodiesel. This research was carried out through several stages, namely refining low-quality crude palm oil, determining the levels of low-quality refined crude palm oil free fatty acids, esterification, synthesis of methyl esters from low-quality crude palm oil with CaO-ZnO catalyst through transesterification, identification of the components composition of the mixture of synthesized methyl ester by GC-MS, and the characterization of the synthesized methyl esters. The results showed that methyl esters could be synthesized from low-quality crude palm oil through a transesterification reaction using CaO-ZnO catalyst. The highest yield was obtained from the use of catalyst 4% w/w of oil with a yield of 84.74%. The components of the constituent compounds of the mixture of synthesized methyl ester were methyl myristate (2.72%), methyl palmitate (54.87%), methyl linoleic (5.78), methyl oleate (26.83%), and methyl stearate (2.55%). The results of the characterization of the synthesized methyl ester showed a density 0.876 g/mL, a viscosity 3.60 cSt, a refractive index 1.448, and an acid number of 0.39 mg KOH/g of methyl ester, resulting in the potential methyl ester as biodiesel.

Liquid–Liquid Equilibria for Ternary Mixtures of γ-Valerolactone + n-Tetradecane + (Butanoic Acid or Hexanoic Acid or Methyl Myristate) at 298.15 K

Novel experimental liquid–liquid equilibrium measurements were performed for three ternary systems containing γ-valerolactone + n-tetradecane + (butanoic acid or hexanoic acid or methyl myristate) at T = 298.15 K. The quantification of the coexisting phases was performed using an indirect method which relies on the variation of physical properties (density) along the binodal curve. The experimental data were successfully correlated by the nonrandom two-liquid and the universal quasichemical models.

Thermophysical properties of fatty acid methyl and ethyl esters

In present study, surface light scattering (SLS) was used for the simultaneous determination of liquid surface tension and kinematic viscosity of twelve fatty acid esters, including six methyl esters (FAMEs) and six ethyl esters (FAEEs). The SLS apparatus was firstly checked with a reference fluid n-dodecane, and a good agreement of our data from SLS with those from literatures could be found. By utilizing this apparatus, both properties were investigated in the temperature ranges between (298 and 448) K for all substances with an exception of methyl myristate and ethyl myristate covering the temperatures between (323 and 448) K due to their high melting points. Additionally, the liquid density and refractive index were determined by an Anton Paar U-tube densimeter between (293 and 453) K and a refractometer from (278 to 358) K, respectively. The surface tension and viscosity data obtained from the SLS experiment were fitted to the van der Waals type and the reciprocal temperature-dependent polynomial equations, respectively. The quadric and linear functions were adopted to correlate the density and refractive index data, respectively. This work improves the data situation for these fatty acid esters especially at elevated temperatures and provides necessary data and models for the crucial thermophysical properties in connection with the design and optimization of the injection system of an internal combustion engine (ICE).

Comparison of biodiesel yield of three processes using sewage sludge as feedstock and byproduct characteristics by in situ transesterification

Recent studies have considered utilizing sewage sludge as feedstock for biodiesel production because of its abundance and high lipid content. In this study, we first compared the biodiesel yields of traditional transesterification, in situ transesterification, and two-step esterification–transesterification under similar conditions. The in situ process generated the highest yield of biodiesel (16.6%) with acceptable purity (94.3%) as verified by GC–MS. The most abundant species in the three methods were methyl hexadecanoate (C16:0), methyl palmitoleate (C16:1), methyl stearate (C18:0), methyl oleate (C18:1), and methyl myristate (C14:0). The byproducts from in situ transesterification included intermediate fluid, residue, and washing water. Given their recyclability, these byproducts showed negligible environmental impact. Methanol, one of the response reagents, can be recovered from the intermediate fluid. More than 80% phosphor was transferred to the intermediate fluid, whereas more than 88% nitrogen remained in the residue of sewage sludge.

Densities and excess molar volumes of methanol with three fatty acid methyl esters from 283.15 to 318.15 K

The main components of biodiesel are fatty acid methyl esters (FAMEs) or fatty acid ethyl esters (FAEE). Methanol is commonly used as a reference molecule for modeling diesel fuel thermodynamics properties. In this work, experimental density data of the binary mixtures of methanol with three fatty acid methyl esters (methyl caprate, methyl laurate, methyl myristate) were reported at atmospheric pressure over the entire composition range at temperatures from 283.15 to 318.15 K. Density measurements were performed using an Anton Paar digital vibrating U-tube densimeter. Excess molar volumes were calculated from the experimental data and correlated as the Redlich-Kister equation for the binary mixtures. The optimized sets of parameters of the equation at each temperature were obtained by the least squares method.

Vapor–Liquid Equilibria of Binary Systems with Long-Chain Organic Compounds (Fatty Alcohol, Fatty Ester, Acylglycerol, and n-Paraffin) at Subatmospheric Pressures

In the past years, the oil and fat industry has been growing on a large scale, mostly due to the need of biodiesel production. Considering this fact, the understanding of thermophysical properties and phase equilibrium of the compounds found in this industry became crucial, that is, acylglycerols, fatty esters, alcohols. Therefore, this work aims to obtain liquid–vapor equilibrium data of the following mixtures: hexadecanol + octadecanol (1.73 kPa), hexadecanol + methyl myristate (1.72 kPa), monononanin + tributyrin (1.69 kPa), and dinonanoin + octacosane (1.70 kPa) by the differential scanning calorimetry technique. As expected, the system with two long-chain alcohols (hexadecanol + octadecanol) showed an ideal behavior. In contrast, the other systems presented nonideal behavior. Experimental data were effectively regressed by the UNIQUAC model. The pure component consistency test and the variation of Van Ness consistency test were applied to all systems. Activity coefficients were modeled using the Line...

Survey on the micro-pollutants presence in surface water system of northern Serbia and environmental and health risk assessment

This study demonstrates the occurrence of 940 organic micro-pollutants in surface water of four rivers, one irrigation canal system, and two lakes in Vojvodina Province, the northern part of Serbia, summing in total eighteen samples. The number of detected chemicals ranged from 22 to 84, with 127 micro-pollutants detected at least once, representing 13% of the studied substances. The targeted compounds include n-alkanes, sterols, polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides polychlorinated biphenyls, pesticides, pharmaceutical active compounds, industrial chemicals, plasticizers, etc. Among the analysed compounds, sterols were the most dominant with maximum quantified concentrations. The substances which were quantified with frequency over 50% were two PAHs (2-methylnaphthalene, benzo(ghi)perylene), five sterols (cholesterol, cholestanol, stigmasterol, fucosterol, beta-sitosterol), three pharmaceuticals and personal care products (L-menthol, diethyltoluamide, caffeine), and ten household chemicals (4-tert-octylphenol, dimethyl phthalate, methyl palmitate, phenylethyl alcohol, 1-nonanol, alpha-terpineol, 2-phenoxy-ethanol, methyl myristate, acetophenone, and 2-ethyl-1-hexanol). The list of priority substances under the European Union Directive 2013/39/EU includes 49 priority substances (PSs) out of which 34 were analysed. Among these, eleven PSs were quantified, and only two compounds (fluoranthene and benzo (a) pyrene) exceeded EU Environmental Quality Standards targeted values. The obtained results were compared with the previously published data that dealt with the same targeted number of micro-pollutants in sediment samples. This revealed connections between the same sampling locations. Environmental risk assessment showed the existence of potential ecological risk as 72% of the obtained values for the ecological hazard index (HI) at investigated locations were higher that the targeted value (HI > 1). Estimated values for hazard quotient (HQ) and hazard index (HI) for non-carcinogenic risk were lower than the targeted value, indicating no non-carcinogenic risk through dermal contact and non-intentional ingestion of water. Estimated values for cancer risk were all below 1 × 10−6, which is not considered to pose significant human health risk.

Experimental studies on the liquid thermal conductivity of three saturated fatty acid methyl esters components of biodiesel

Abstract One of the attempts to reduce the consumption of fossil fuels is to replace them with renewable and clean fuels. Among these fuels, biodiesel has been considered as a promising alternative to petroleum diesel fuel. Thermal conductivity of biodiesel is a very important thermophysical property for its applications. In this work, the liquid thermal conductivity of three saturated fatty acid methyl esters (methyl myristate, methyl laurate and methyl caprate), usually the significant biodiesel components, was measured with the temperature ranging within (304–402) K, (283–402) K, (267–400) K, respectively. The total standard uncertainty of the experimental results was estimated to be less than 2% and the repeatability was better than ± 0.5%. The thermal conductivity data of each substance were fitted as a function of temperature, and the average absolute relative deviation and maximum absolute relative deviation between the experimental data and calculated results were 0.13% and 0.44% for methyl myristate, 0.21% and 0.53% for methyl laurate, 0.28% and 0.80% for methyl caprate, respectively.

Biodiesel synthesis optimization from wet and dry based microalgae chlorella vulgaris by reaction time arrangement

Microalgae have the potential to be used as the raw material for biodiesel synthesis. One of promising microalgae species to be used is Chlorella vulgaris. However, in the process of biodiesel synthesis from microalgae needs to be optimized. In this study, optimization of biodiesel synthesis from wet and dry based microalgae Chlorella vulgaris has been studied. Optimization done by arranges the time of transesterification reaction. Transesterification reaction has been done using KOH catalyst. The reaction time was varied at 20, 40, and 60 minutes. From the results, the highest yields of biodiesel are obtained on the 40 minutes reaction time with biodiesel yield is 75% for wet based microalgae and 62.8% for dry based microalgae. Biodiesel from dry based microalgae Chlorella vulgaris composed by several types of FAME, including saturated FAME such as methyl myristate (4.48%), methyl palmitate (28.3%), and methyl stearate (17.1%), and also composed by unsaturated FAME such as methyl palmitoleate (11.1%) and methyl oleate (39.1%).

Experimental investigations on the thermophysical properties of methyl myristate in alcoholic solutions

Due to the limitations of using biodiesel directly or blended with petroleum diesel, alcohols are always employed as the additives to improve the certain properties of biodiesel. In this work, experimental investigations are conducted on the thermophysical properties, especially the density and viscosity, of binary mixtures containing the component of the biodiesel, namely methyl myristate, with higher alcohols, including 1-propanol, 1-butanol and 1-pentanol at atmospheric pressure from 303.15 K to 333.15 K. The Vogel-Fulcher-Tammann equation is introduced to correlate the viscosity. The derived property of thermal expansion coefficient is calculated based on the experimental density. The excess properties are obtained to further understand the interactions between the ester and the alcohols. The positive value of the excess molar volume and negative value of viscosity deviation are observed, indicating that the increasing contribution of the repulsive forces between methyl ester and the alcohols.

Pathogenic bacteria enhance dispersal through alteration of Drosophila social communication

Pathogens and parasites can manipulate their hosts to optimize their own fitness. For instance, bacterial pathogens have been shown to affect their host plants’ volatile and non-volatile metabolites, which results in increased attraction of insect vectors to the plant, and, hence, to increased pathogen dispersal. Behavioral manipulation by parasites has also been shown for mice, snails and zebrafish as well as for insects. Here we show that infection by pathogenic bacteria alters the social communication system of Drosophila melanogaster. More specifically, infected flies and their frass emit dramatically increased amounts of fly odors, including the aggregation pheromones methyl laurate, methyl myristate, and methyl palmitate, attracting healthy flies, which in turn become infected and further enhance pathogen dispersal. Thus, olfactory cues for attraction and aggregation are vulnerable to pathogenic manipulation, and we show that the alteration of social pheromones can be beneficial to the microbe while detrimental to the insect host.

Densities of FAMEs or FAEEs with ethanol at temperatures from 283.15 to 318.15 K

ABSTRACTEthanol is usually considered as an additive to blend with biodiesels to improve its cold flow characteristics. The thermophysical properties of ethanol with biodiesels are therefore of interest in its applications. In the present work, the densities of ethanol with six components of biodiesel (including methyl caprate, methyl laurate, methyl myristate, ethyl caprylate, ethyl caprate and ethyl laurate) mixtures were measured from 283.15 to 318.15 K and at atmospheric pressure in the overall composition range. Redlich–Kister equation was used to correlate the excess molar volumes of the mixtures, which were calculated from the experimental densities. In addition, Apelblat’s equation was extended to correlate and predict the densities of the studied mixtures as a function of concentration and temperature.

Speed of Sound in Methyl Caprate, Methyl Laurate, and Methyl Myristate: Measurement by Brillouin Light Scattering and Prediction by Wada’s Group Contribution Method

The speed of sound related with the isentropic bulk modulus has a significant effect on fuel injection and NOx emissions in diesel engines. Nevertheless, the speed of sound in pure fatty acid (methyl and ethyl) esters, which were widely used and investigated as the main components of biodiesel, is scarce in the literature. Most of the experimental data are available only at atmospheric pressure or in a narrow range of temperatures. In this work, the speed of sound in three fatty acid methyl esters [FAMEs = caprate (MeC10:0), laurate (MeC12:0), myristate (MeC14:0)] was measured by the Brillouin light scattering method. The measurements were carried out at temperatures ranging from 288 to 498 K along four isobaric lines of 0.1, 4.0, 7.0, and 10.0 MPa. The relative expanded uncertainty in the speed of sound was estimated to be less than 1.0%. A rational function that correlates 1/c2 as a function of the pressure and temperature was used to correlate the experimental speed of sound in liquid MeC10:0, MeC12:0,...

Dung dinner call

Fruit flies are known for using pheromones to tell their buddies about new food sources and where to find romance. But the fruit flies aren’t just releasing these chemicals from their pheromone-secreting glands, they’re also depositing the molecular messages in their excrement. The first chemical analysis of Drosophila feces, performed by Bill S. Hansson, Markus Knaden, and colleagues of the Max Planck Institute for Chemical Ecology in Jena, has shown that fruit fly poop left behind on ripe blueberries contains a variety of pheromones, including methyl laurate, methyl myristate, and methyl palmitate, which are involved in signals for aggregating and mating (J. Chem. Ecol. 2016, DOI: 10.1007/s10886-016-0737-4). The presence of sex and feeding pheromones in fly droppings may inspire other flies to lay eggs nearby, so that larvae can dine on predigested food in feces before advancing to the ripe fruit, note the authors. The team hopes that studying the