scholarly journals Improvement of Chemical Composition of Tisochrysis lutea Grown Mixotrophically under Nitrogen Depletion towards Biodiesel Production

Molecules ◽  
2020 ◽  
Vol 25 (20) ◽  
pp. 4609
Author(s):  
Adel W. Almutairi

In the present study, the marine microalga Tisochrysis lutea was cultivated mixotrophically in F2 growth medium with sodium acetate as exogenous carbon source. The medium was composed of different concentrations of nitrogen to determine the impact of nitrogen depletion on cellular growth and chemical composition. Nitrogen depletion led to severely decreased growth and protein content. However, mild nitrogen depletion (0.22 mM NaNO3) led to maximum lipid yield. The fatty acid methyl ester profile also showed increased unsaturation as the nitrogen content decreased. Growth in nitrogen-free medium increased the proportions of mono- and poly-unsaturated fatty acids, while the proportion of saturated fatty acids decreased. Growth under all tested nitrogen levels showed undetectable fatty acids with ≥4 double bonds, indicating these fatty acids had oxidative stability. In addition, all tested nitrogen concentrations led to specific gravity, kinematic viscosity, iodine value, and cetane number that meet the standards for Europe and the U.S.A. However, growth in the presence of nitrogen deficiency enhanced the higher heating value of the resulting biodiesel, a clear advantage from the perspective of energy efficiency. Thus, mixotrophic cultivation of T. lutea with nitrogen limitation provides a promising approach to achieve high lipid productivity and production of high-quality biodiesel.

2014 ◽  
Vol 59 (2) ◽  
pp. 141-150
Author(s):  
Mladen Popovac ◽  
Dragan Radojkovic ◽  
Milica Petrovic ◽  
Marija Gogic ◽  
Dragan Stanojevic ◽  
...  

The aim of this study was to evaluate the chemical composition of the back fat tissue of mangalitsa pig and meaty pig breeds and their crosses, and the pigs that were fed with feed that was enriched or unenriched with oil, from the aspect of the production of biodiesel, where the starting material for the fuel would be the fat tissue of pigs. By examining the impact of breed and oil content in feed, it was found that chemical parameters (fat, water, protein, saturated and unsaturated fatty acids) show statistically significant variation under the influence of these factors. The highest fat content (89.39%), which is essential for conversion of fat into biodiesel, was found in back adipose tissue of mangalitsa breed, while the lowest fat content (86.10%) was found in the back fat tissue of meaty breeds and their crosses. Favorable ratio of saturated to unsaturated fatty acids (37.92% : 62.07%), on which some physical properties of the fuel depend, was found in the back fat tissue of pigs that were fed with feed enriched with oil, and the largest proportion of saturated fatty acids, i.e. the most unfavorable fatty acid composition (40.90% : 59.09%) was found in the back fat tissues of pigs that were fed with feed unenriched with oil. The lowest content of saturated fatty acids and water (7.44%), as the key factors that determine the cetane number of the fuel and the fuel production process, indicates that the most suitable raw material for the production of biodiesel is the fat tissue of pigs that were fed with food that contained a certain amount of oil.


Energies ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 7148
Author(s):  
Ayesha Mushtaq ◽  
Muhammad Asif Hanif ◽  
Muhammad Zahid ◽  
Umer Rashid ◽  
Zahid Mushtaq ◽  
...  

Biodiesel has attracted considerable interest as an alternative biofuel due to its many advantages over conventional petroleum diesel such as inherent lubricity, low toxicity, renewable raw materials, biodegradability, superior flash point, and low carbon footprint. However, high production costs, poor low temperature operability, variability of fuel quality from different feedstocks, and low storage stability negatively impact more widespread adoption. In order to reduce production costs, inexpensive inedible oilseed alternatives are needed for biodiesel production. This study utilized inedible tamarind (Tamarind indica) seed oil as an alternative biodiesel feedstock, which contained linoleic (31.8%), oleic (17.1%), and lauric (12.0%) acids as the primary fatty acids. A simple and cost-effective high vacuum fractional distillation (HVFD) methodology was used to separate the oil into three fractions (F1, F2, and F3). Subsequent transesterification utilizing basic, acidic, and enzymatic catalysis produced biodiesel of consistent quality and overcame the problem of low temperature biodiesel performance. The most desirable biodiesel with regard to low temperature operability was produced from fractions F2 and F3, which were enriched in unsaturated fatty acids relative to tamarind seed oil. Other properties such as density and cetane number were within the limits specified in the American and European biodiesel standards.


2014 ◽  
Vol 16 (6) ◽  
pp. 1076-1084

<div> <p>An unstandarised biodiesel made from Camelina<em> sativa </em>oil, having over a 90 percent by weight of unsaturated fatty acids, were transformed into an epoxidised biodiesel that satisfy the requirements for iodine value, linolenic acid methyl ester content, cetane number, polyunsaturated fatty acids content, and viscosity established by the EN 14214 and ASTM D 6751 standards. The epoxidation reaction was carried out at 60 &deg;C using peroxyacetic acid generated <em>in situ</em> and sulphuric acid as catalyst. A conversion of 60 % of double bonds was reached after 3 hours of reaction. However, only one hour was needed to get standard requirements and to avoid the epoxide ring opening side reaction that leads to hydroxyl groups. Besides, it was also observed that the formation of hydroxyl groups increases the kinematic viscosity of the biodiesel, being deleterious for the biodiesel properties.&nbsp;</p> </div> <p>&nbsp;</p>


2020 ◽  
Vol 44 (1) ◽  
Author(s):  
Sayeda M. Abdo ◽  
Guzine I. El Diwani ◽  
Kamel M. El-Khatib ◽  
Sanaa A. Abo El-Enin ◽  
Mohammed I. El-Galad ◽  
...  

Abstract Background Microalgae cells can be identified as a potential source for new and renewable energy. The economic investigation for biodiesel and bio-active compound production from the microalgae community (Bloom), which are collected from the high rate algal pond (HRAP) constructed to treat municipal wastewater at Zenin wastewater treatment plant, Giza, was the main target of study. Results The microscopical examination showed that Scenedesmus obliquus is the dominant species. The total carotenoids were extracted using jojoba oil and determined by high-performance liquid chromatography (HPLC) to reach 81.44 μg/g. The biodiesel production through acid transesterification reaction recorded 70.6% of fatty acid methyl ester content with high cetane number (44) and low acid value. Such results prove that the obtained biodiesel has better ignition quality. The total phenolic and flavonoid compounds have been derived from the remaining biomass to give 5.36 ± 0.03 and 1.50 ± 0.19 mg/g respectively. Finally, total proteins and carbohydrates content in algal cells were recorded 54.3 and 1.5 mg/g successively Conclusion The preliminary economic evaluation showed that the production of biodiesel and carotenoids from the microalgae growing in municipal wastewater can be considered, as a techno-economic feasible process.


2014 ◽  
Vol 32 (2) ◽  
pp. 255-265 ◽  
Author(s):  
Omar Montenegro R. ◽  
Stanislav Magnitskiy ◽  
Martha C. Henao T.

This study was conducted to assess fruit and seed yield, oil content and oil composition of Jatropha curcas fertilized with different doses of nitrogen and potassium in Espinal (Tolima, Colombia). The yields ranged from 4,570 to 8,800 kg ha-1 of fruits and from 2,430 to 4,746 kg ha-1 of seeds. These yields showed that the fertilizer dose of 150 kg ha-1 N + 120 kg ha-1K increased fruit production by 92% and seed production by 95%, which represents an increase of about 100% in oil production, which increased from 947 to 1,900 kg ha-1. The total oil content in the seeds ranged from 38.7 to 40.1% (w/w) with a high content of the unsaturated fatty acids oleic (> 47%) and linoleic acid (> 29%). The highest content of oleic acid in the seed oil was from the unfertilized control plants and plants with an application of 100 kg ha-1 of N and 60 kg ha-1 of K, with an average of 48%. The lowest content of oleic acid was registered when a low dose of nitrogen and a high level of potassium were applied at a ratio of 1:2.4 and doses of 50 kg ha-1 N + 120 kg ha-1 K, respectively. Low contents of the saturated fatty acids palmitic (13.4%) and stearic (7.26%) were obtained, making this oil suitable for biodiesel production. The nitrogen was a more important nutrient for the production and quality of oil in J. curcas than potassium under the studied conditions of soil and climate.


Agronomy ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1976
Author(s):  
Filipa Mandim ◽  
Spyridon A. Petropoulos ◽  
Kyriakos D. Giannoulis ◽  
Celestino Santos-Buelga ◽  
Isabel C. F. R. Ferreira ◽  
...  

The present study evaluated the effect of maturity stage on the chemical composition of cardoon bracts. Plant material was collected in Greece at eight different maturation stages (C1–C8) and the chemical composition was analyzed in regard to lipidic fraction and the content in fatty acids, tocopherols, organic acids, and free sugars. Samples of late maturity (C6–C8) revealed the lowest lipidic content, while a total of 29 fatty acids was identified in all the samples, with palmitic, stearic, oleic, and eicosatrienoic acids present in the highest levels depending on harvesting time. Immature (C1) and mature (C8) bracts were more abundant in saturated fatty acids (SFA) than bracts of medium-to-late maturity (C5, C6), where the monounsaturated fatty acids (MUFA) were the prevalent class. The α- and γ-tocopherols were the only identified isoforms of vitamin E, while the highest content was observed in sample C8 (199 µg/100 g dry weight (dw). The detected organic acids were oxalic, quinic, malic, citric, and fumaric acids, while fructose, glucose, sucrose, trehalose, and raffinose were the main detected sugars. The results of the present study allowed us to reveal the effect of maturity stage on cardoon bracts chemical composition and further valorize this byproduct by improving its bioactive compounds content.


Molecules ◽  
2020 ◽  
Vol 25 (9) ◽  
pp. 2107
Author(s):  
Jean Claude Nzayisenga ◽  
Calle Niemi ◽  
Lorenza Ferro ◽  
Andras Gorzsas ◽  
Francesco G. Gentili ◽  
...  

Rapid rises in atmospheric CO2 levels derived from fossil fuel combustion are imposing urgent needs for renewable substitutes. One environmentally friendly alternative is biodiesel produced from suitable microalgal fatty acids. Algal strains normally grow photoautotrophically, but this is problematic in Northern areas because of the light limitations for much of the year. Mixotrophic and particularly heterotrophic strains could be valuable, especially if they can be cultivated in municipal wastewater with contents of nutrients such as nitrogen and phosphorous that should be reduced before release into receiving water. Thus, the aim of this study was to screen for microalgal strains suitable for heterotrophic cultivation with a cheap carbon source (glycerol) for biodiesel production in Nordic, and other high-latitude, countries. One of the examined strains, a Desmodesmus sp. strain designated 2-6, accumulated biomass at similar rates in heterotrophic conditions with 40 mM glycerol as in autotrophic conditions. Furthermore, in heterotrophic conditions it produced more fatty acids, and ca. 50% more C18:1 fatty acids, as well as showing a significant decrease in C18:3 fatty acids, all of which are highly desirable features for biodiesel production.


2016 ◽  
Vol 8 (6) ◽  
pp. 149 ◽  
Author(s):  
Cunfang Wang ◽  
Xinman Lou ◽  
Jianmin Wang

<p>In this study, the fatty acid profile and fat stability for seven consecutive days of raw milk and pasteurized milk from Laoshan goats have been evaluated by gas chromatography-mass spectrometry (GC-MS) after fatty acid methyl ester. The results showed that the concentrations of short chain fatty acids (SCFA) and saturated fatty acids (SFA) significantly increased by 47.36% and 11.68% after pasteurization respectively, while the concentrations of unsaturated fatty acids (UFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) decreased by 26.08%, 26.45% and 22.15% respectively. The C10:0 (5.39%-8.57%), C12:0 (3.13%-5.28%), C14:0 (8.12%-11.87%), C16:0 (25.59%-28.53%), C18:0 (14.60-13.69%) and C18:1 (33.91-24.92%) are the most predominant fatty acids of Laoshan goat milk with significant differences. Moreover, the fat stabillity for seven consecutive days of raw milk and pasteurized milk was detected by sedimentation rate (R). The fat stability in pasteurized milk was more stable than that in raw milk, the sedimentation rate of raw milk and pasteurized milk consisted in a progressive decrease in the seven days by 82.99% and 79.77% respectively. What’s more, significant difference was observed from 1st day to 4th day between raw milk and pasteurized milk, however, there was no significance from 5th to 7th. This is the first report to fully characterize the fatty acid contents and fat stability of Laoshan goat raw milk and its pasteurized milk and it provided a certain theoretical basis for the research and development of goat milk functional product.</p>


2016 ◽  
Vol 41 (1) ◽  
pp. 45-49 ◽  
Author(s):  
N.C. Tiven ◽  
I. P. Siwa ◽  
L. Joris

This study was conducted to determine the effect of Citrus hystrix as fat protector on unsaturated fatty acids, cholesterol and chemical composition of lamb meat. The research design applied was completely randomized design with 3 treatments and 5 replications. Fifteen local male lambs aged 9-12 months weighing 14-17 kg, were divided into 3 groups of different diet treatments (P0 : sheeps were only given a basal diet; P1 : sheeps are given basal diet and 3% cooking oil; P2 : sheeps are given basal diet, 3% cooking oil and protected by 3% Citrus hystrix powder). The data were analyzed by analysis of variance, the differences among treatments were tested by Duncan’s New Multiple Range Test. The results showed meat from sheeps that consume P2 diet has a total fatty acid and polyunsaturated fatty acids content were higher (P


2019 ◽  
Vol 14 (5) ◽  
pp. 1934578X1984414 ◽  
Author(s):  
Katarzyna Wolosik ◽  
Agnieszka Markowska

Among 60-70 species of Amaranthaceae, only three are grain-producing species and Amaranthus cruentus is one of them. It stands out for its significant chemical composition. The high protein content and amino acid composition give amaranth medicinal benefits such as cholesterol lowering, antioxidant, anticancer, anti-allergic, and antihypertensive activity. The fixed oil yield obtained by cold-pressing the grain is only 7-8%, but these lipids are valuable due to the presence of unsaturated fatty acids, tocopherols, tocotrienols, phytosterols, and squalene, which are not present in the same composition in other common oils. Among them, squalene is highly desirable.


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