Free Fatty Acids In Oil Research Articles

Physiological Doses of Oleic and Palmitic Acids Protect Human Endothelial Cells from Oxidative Stress.

Oxidative stress has been proposed to be a pathogenic mechanism to induce endothelial dysfunction and the onset of cardiovascular disease. Elevated levels of free fatty acids can cause oxidative stress by increasing mitochondrial uncoupling but, at physiological concentrations, they are essential for cell and tissue function and olive oil free fatty acids have proved to exhibit beneficial effects on risk factors for cardiovascular disease. We hypothesize that realistic concentrations within the physiological range of oleic (OA) and palmitic (PA) acids could be beneficial in the prevention of oxidative stress in vascular endothelium. Hence, pre-treatment and co-treatment with realistic physiological doses of palmitic and oleic acids were tested on cultured endothelial cells submitted to a chemically induced oxidative stress to investigate their potential chemo-protective effect. Cell viability and markers of oxidative status: reactive oxygen species (ROS), reduced glutathione (GSH), malondialdehyde (MDA), glutathione peroxidase (GPx) and glutathione reductase (GR) were evaluated. As a conclusion, the increased ROS generation induced by stress was significantly prevented by a pre- and co-treatment with PA or OA. Moreover, pre- and co-treatment of cells with FFAs recovered the stress-induced MDA concentration to control values and significantly recovered depleted GSH and normalized GPx and GR activities. Finally, pre- and co-treatment of cells with physiological concentrations of PA or OA in the low micromolar range conferred a substantial protection of cell viability against an oxidative insult.

Carbon-templated meso-design of nanostructured CeAPSO-34 for biodiesel production from free fatty acid and waste oil

The SAPO-34 zeotype with suitable physicochemical properties, was used to produce biodiesel as a clean fuel. The micropore nature of this catalyst limits the reaction because elainic acid molecules are too large to penetrate and access the internal pores of zeotype. The physicochemical properties of the synthesized catalysts were evaluated and compared using BET, XRD, TPD, EDX, FESEM, and HRTEM analyses. The simultaneous use of a carbon template and a heteroatom for doping in the synthesis of the catalyst (MCeAPSO-34) has a synergistic effect on increasing the pore diameter up to 4.1 nm. As expected, the MCeAPSO-34 zeotype gained 17, 12, and 27% more conversion rates than the CeAPSO-34 (doping effect), MSAPO-34 (carbon-template effect), and conventional SAPO-34 zeotypes in the production of biodiesel from elainic acid, respectively. Accommodation of CeO2 on the nanostructured MCeAPSO-34 zeotype by the solvothermal method increased the zeotype acidic sites from 73% to 89%. The use of ultrasound energy for distribution of the active phase increased the catalyst acidity and the conversion of 95% was obtained for the Ce/MCeAPSO-34 (U) catalyst. This catalyst has also converted 93% of the synthetic waste oil into biodiesel as a clean fuel.

Physicochemical Properties, Antioxidant and Antimicrobial Activities of Unripe Green and Ripened Yellow Banana (Musa sp.) Peel and Pulp Oil Extracts

Background: Banana peel (Musa Sp.) is more nutritional and rich in phytochemical compounds than its pulp. All parts of the banana plant have medicinal applications. Damage from free radicals at the cellular level causes cell inflammation, increasing the risk of damage from sunlight, radiation, and related development of skin cancer. Objective: The purpose of this study was to assess the physicochemical properties, antioxidant, and antimicrobial activities of unripe green and yellow ripened banana fruit peels and pulp oil extracts. Methods: The oil extraction was done in Soxhelt apparatus using petroleum ether as a solvent. Then, the oil extracts were assessed based on the determination of oil yield, acid value, percent free fatty acid, peroxide value, and free radical scavenging activity using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and hydrogen peroxide, and ascorbic acid. The antioxidant and antimicrobial activities were determined based on ascorbic acid content, DPPH and hydrogen peroxide scavenging activities. The antimicrobial experiment was arranged in completely randomized factorial design with three replications. Results: The result indicated that significantly the highest oil yield (2.60±0.21%), acid value (2.66±0.20%), and free fatty acids (1.34±0.10%) were recorded for green peel oil extract. Significantly, the highest DPPH radical scavenging activity was recorded for green peel (5.85%) followed by green pulp (4.80) and the least for yellow peel (4.50). Ascorbic acid and hydrogen peroxide scavenging activity were significantly higher for yellow peel and green pulp oil extract extracts than for green peel oil extract. The strongest antibacterial activity with the maximum zone of inhibition (15.5mm), minimum inhibitory concentration (0.125μg/ml), and corresponding minimum bactericidal concentration (0.25 μg/ml) was recorded for ripened peel oil extract against Staphylococcus aureus. The antifungal activity of the oil extract presented the highest zone of inhibition (15.67mm), minimum inhibitory concentration (0.125 μg/ml) and corresponding minimum fungicidal concentration (0.25 μg/ml) were recorded for unripe green banana fruit pulp oil extract against Aspergillus versicolor. Conclusion: The result indicated that the banana fruit peel oil extracts demonstrated differential antioxidant and antimicrobial potentials. Thus, the banana peel waste oil extracts proved to have potential sustainable applications in nutritional and drug development technologies.

Lipase catalysis: an environmentally friendly production for polyol esters (biolubricant) from microalgae oil

ABSTRACT This study aims to investigate the optimized lipase-catalysed esterification reaction from novel feedstock microalgae (Chlorella protothecoides) oil-free fatty acids (FFAs) for biolubricant (Trimethylolpropane (TMP)-triesters) synthesis. FFAs were obtained from microalgae oil by enzymatic hydrolysis. Response surface methodology (RSM) with the central composite design was performed to investigate the effect of experimental factors (lipase amount, TMP/FFAs molar ratio, reaction temperature) on the FFAs conversion and also investigated to resolve the optimum design points. After the experimental studies, the highest FFAs conversion of 93% with 92% triester and 8% mono, di esters contents were found when the lipase amount was 5.5%. TMP/FFAs molar ratio was 0.33 and the reaction temperature value was 60°C. The model fitted with the experimental values with R 2 = 0.97. It was also supported by gas chromatography and FTIR analyses that the product obtained was a lubricant.

Monitoring of free fatty acid content in mixed frying oils by means of LF-NMR and NIR combined with BP-ANN

The free fatty acid (FFA) is an essential indicator to determine the discard point of frying oils, however, the current detection method of FFA in oil is laborious. This research established two non-destructive approaches based on low field nuclear magnetic resonance (LF-NMR), near Infrared (NIR) spectra, and back-propagation artificial neural network (BP-ANN) algorithm for monitoring the FFA content of fried oil samples. 105 used frying oils, representing various frying degree, were detected using LF-NMR, NIR and reference method. HCA and PCA were used for natural clustering of LF-NMR parameters (S21, S22, S23, T21, T22, and T23) and NIR spectroscopy. Finally, the value of the correlation coefficient (R 2 ) manifested that the accuracy of LF-NMR model and NIR model reached 0.850, 0.963, respectively. The R 2 value of NIR model was 0.113 higher than that of LF-NMR model, indicating NIR spectroscopy of used frying oil could be a more accurate method for monitoring the FFA content in the oil using the BP-ANN model. • The changes of FFA of frying oil with the increase of frying batch were investigated. • HCA and PCA were used for natural clustering of LF-NMR and NIR parameters. • Both LF-NMR and NIR were applied for monitoring FFA values using the BP-ANN model. • NIR-FFA model was more accurate than LF-NMR-FFA model.

Effect of frying oil stability over repeated reuse cycles on the quality and safety of deep-fried Nile tilapia fish (Oreochromis niloticus): a response surface modeling approach

ABSTRACT Fresh water fish is considered a source of good quality proteins and essential fats. Frying is among widely used fish preparation techniques globally. Deep-frying oil quality with repeated uses, has been a concern. This research investigated the influence of frying oil stability (expressed as levels of peroxide values (0.2, 1.2 meq/kg) and free fatty acids (0.05, 0.13% palmitic acid)) over repeated uses (1,6 cycles) on the oxidative stability and essential nutrients of fried fish using a response surface approach, with the objectives of generating information relevant for the improvement of community health outcomes, with a special focus of this particular research was on trends, but not optimization. The frying oil and fried fish quality were adequately explained by response surface model and supported by principal component analysis. The result showed that the oxidative stability of both the frying oil and fried fish were deteriorating over the reuse cycles of the frying oil (with increasing trends of unhealthy fats, saturated and trans) corresponding to decreasing trends in the healthy fat components and vitamin A). It was also indicated that the essential fats (omega 3, omega 6, cis, vitamin A), were decreased while the risky fats (saturated, trans) were increased along with the frying cycles. The result revealed the urgent need for regulating frying oil and fried food qualities, particularly in developing countries.

Enzymatic ethanolysis of high free fatty acid jatropha oil using Eversa Transform

A reduction of the cost of enzymatic biodiesel is crucial to make it competitive with known technologies. A single-step process for the conversion of high free fatty acid oils into fatty acid ethyl esters using a low-cost lipase was developed.

PHYSICOCHEMICAL PROPERTIES AND BIOLOGICAL ACTIVITIES OF MANGO (MAGNIFERA INDICA L.) SEED KERNEL AND PEEL OILS

The peel and kernels mango (Mangifera indica L.) processing by products can be used as a source of valuable products. Therefore, the present study was attempted to study physicochemical properties, antioxidant and antimicrobial activities of mango seed kernel and peel wastes. The result of physicochemical properties indicated that significantly higher oil yield (38.75±1.77), specific gravity (0.86±0.04), acid value (2.66±0.20) and free fatty acid value (1.34±0.12); and higher DPPH (16.70±0.70) antioxidant activities were recorded for mango seed oil extract. However, significantly higher hydrogen peroxide scavenging activity (HPSA, 31.10±1.70) and ascorbic acid (43.00±2.73) were recorded for fruit peel oil extract. Stronger antibacterial activity with maximum zone of inhibition (16.50 mm), minimum inhibitory concentration MIC (0.10µl/ml) and corresponding minimum bactericidal concentration MBC (0.20 µl/ml) was recorded for seed oil extract against S. aureus. Stronger antifungal activity with maximum zone of inhibition (16.47 mm), MIC (0.05 µl/ml, the least value) and MFC (0.10 µl/ml) for seed oil extract against C. albicans. It can be concluded from the results of present study that seed oil extract was found to be more effective antioxidant and antimicrobial potential than peel oil extract in mango (M. indica L.)

Biodiesel production from Bauhinia variegata seeds oil using homogeneous catalyst

At present, a large amount of biodiesel is produced from the non-edible and waste cooking oils using alcohol and catalyst (acid, alkaline). The free fatty acids in the oils react fast with the alkaline catalyst to produce soap that inhibits the reaction. In the present work, a two-step trans-esterification process is developed to convert the high free fatty acid oils to its mono-esters. In the first step, acid catalyzed esterification reduces the free fatty acid level of the oil to less than 1.9%, and the alkaline catalyzed trans-esterification process converts the yields of the first step to its mono-esters and glycerol during the second step. The main factors such as alcohol and oil a molar ratio, catalyst amount, reaction time and temperature are optimized. The property of biodiesel obtained is similar to that of petro-diesel.

Repellent and acaricidal activity of coconut oil fatty acids and their derivative compounds and catnip oil against Amblyomma sculptum

This study was carried out aiming to evaluate the repellent and acaricidal activity of major ingredient compounds from coconut oil including their methyl ester derivatives and catnip oil against nymphs and larvae of Amblyomma sculptum. Repellent candidates, coconut oil free fatty acids (coconut FFA mainly C12, C10 and C8 acid); lauric acid (C12 acid); capric acid (C10 acid); methyl laurate; methyl caprate and 10 % each of C12, C10 and C8 acid (1:1:1) in lavender oil formulation (CFA in lavender formula) and catnip oil (Nepeta cataria), were screened using a Petri dish bioassay to assess repellency. Catnip oil, methyl caprate, methyl laurate, and CFA in lavender formulation repelled ticks strongly (P < 0.05) at almost all times evaluated, with an average of 77.8–100% repellency. Some candidate repellents with consistent strong repellence observed were selected for further evaluation, with coconut CFA in lavender formula showing a repellency lasted up to 7 days, while those of catnip oil and methyl caprate were active for 4 and 3 days, respectively. For the acaricide test, five concentrations (2.5; 5; 10; 15 and 20 mg/mL) were evaluated using the larval packet test. Only CFA in lavender formula and two methyl esters showed acaricidal activity, with methyl laurate presenting the strongest toxicity at 15 mg/mL concentration, which was effective against more than 93 % of the tested larvae. Catnip oil caused no mortality of A. scultptum larvae in all concentrations tested.

Production of Biodiesel From Croton gratissimus Oil Using Sulfated Zirconia and KOH as Catalysts

Optimization studies for the esterification and transesterification of oil extracted from Croton gratissimus grains were carried out using the response surface methodology (RMS) that utilizes the central composite design (CCD) and the analysis of variance (ANOVA). A 23 full-factorial rotatable CCD for three independent variables at five levels was developed in each case, giving a total of 20 experiments needed per study. The three design factors chosen for study were the catalyst concentration, methanol-to-oil ratio, and the reaction temperature. The values of the acid value of oil (in esterification) and the percentage FAME yield and FAME purity (in transesterification) were taken as the responses of the designed experiments. In the optimization of the esterification and transesterification processes, the ANOVA showed that both quadratic regression models developed were significant. The optimum operating conditions for the esterification process that could give an optimum acid value of 2.693 mg KOH/g of oil were found to be 10.96 mass% SO42–/ZrO2 catalyst concentration, 27.60 methanol-to-oil ratio, and 64°C reaction temperature. In the optimization of the transesterification process, the model revealed that the catalyst concentration and the methanol-to-oil ratio were the terms that had the most influence on the % FAME yield and the % FAME purity of the final biodiesel product. From the combined regression model, it was established that optimum responses of the 84.51% FAME yield and 90.66% FAME purity could be achieved when operating the transesterification process at 1.439 mass% KOH catalyst concentration, 7.472 methanol-to-oil ratio, and at a temperature of 63.50°C. Furthermore, in the two-step biodiesel synthesis, a predominantly monoclinic-phased sulfated zirconia (SO42–/ZrO2) catalyst exhibited high activity in the esterification of high free fatty acid oil extracted from Croton gratissimus grains. A 91% reduction in the acid value of the Croton gratissimus oil from 21.46 mg KOH/g of oil to 2.006 mg KOH/g of oil, well below the 4 mg KOH/g of oil maximum limit, was achieved. This resulted in the high FAME yield and purity of the biodiesel produced in the subsequent catalytic transesterification of oil using KOH.

Synthesis of biodiesel from non-edible (Brachychiton populneus) oil in the presence of nickel oxide nanocatalyst: Parametric and optimisation studies

The present study defines a novel green method for the synthesis of the nickel oxide nanocatalyst by using an aqueous latex extract of the Ficus elastic. The catalyst was examined for the conversion of novel Brachychiton populneus seed oil (BPSO) into biodiesel. The Brachychiton populneus seeds have a higher oil content (41 wt%) and free fatty acid value (3.8 mg KOH/g). The synthesised green nanocatalyst was examined by the Fourier transform infrared (FT-IR) spectroscopy, energy dispersive X-Ray (EDX) spectroscopy, X-Ray diffraction (XRD) spectroscopy and scanning electron microscopy (SEM). The obtained results show that the synthesised green nanocatalyst was 22–26 nm in diameter and spherical-cubic in shape with a higher rate of catalytic efficiency. It was utilised further for the conversion of BPSO into biofuel. Due to the high free fatty acid value, the biodiesel was synthesised by the two-step process, i.e., pretreatment of the BPSO by means of acid esterification and then followed by the transesterification reaction. The acidic catalyst (H2SO4) was used for the pretreatment of BPSO. The optimum condition for the transesterification of the pretreated BPSO was 1:9 of oil-methanol molar ratio, 2.5 wt % of prepared nanocatalyst concentration and 85 °C of reaction temperature corresponding to the highest biodiesel yield of 97.5 wt%. The synthesised biodiesel was analysed by the FT-IR and GC-MS technique to determine the chemical composition of fatty acid methyl esters. Fuel properties of Brachychiton populneus seed oil biodiesel (BPSOB) were also examined, compared, and it falls in the prescribed range of ASTM standards.

Quality Characteristics of Stored Varieties of Tiger Nut Oil

Quality characteristic of stored tiger nut oil was studied. Different tiger nut cultivars were sourced and their oil extracted using hexane. Oil were stored in plastic bottles for 12 weeks at room temperature revealed moisture content of 0.39%, 0.48%, and 0.30% for black, brown and yellow varieties respectively. Thiobarbituric acid value of stored tiger nut oil were 0.49 malondialdehyde/mg black tiger nut oil, 0.51 malondialdehyde/mg yellow, and 0.35 malondialdehyde/mg for brown cultivars respectively. The free fatty acids (FFA) of the tiger nut oil ranged between 0.75%-0.87%, 0.38%-0.41% and 0.20%-0.21% for varieties respectively. The black tigernut oil and the brown tiger nut oil free fatty acids increased during oil storage. Peroxide values decrease between 5.76 to 5.50 meq/kg, 5.85 to 5.68 meq/kg and 4.36 to 4.32 meq/ for varietal cultivars respectively. During storage periods tiger nut oil from varied sources confers oil stability. The properties measured revealed food grad and commercial use of varietal tiger nut oils because they are within limits as marked by standard.

Production of green transportation fuels from Brassica carinata oil: A comparative study of noble and transition metal catalysts

Herein, we present the production of jet and diesel range hydrocarbons from non-edible hexane-extracted Brassica carinata oil. The influence of four heterogeneous catalysts (two noble metal catalysts: Pd/C and Ru/C, and two transition metal catalysts: Ni/C and Ni/SiO2-Al2O3) was investigated at 400 °C. The catalysts were characterized using XRD, Raman spectroscopy, TEM, SEM, TGA, TG-TPR, and BET specific surface area and pore size analyzer. The upgrading experiments consisted of three different approaches: 1) single-step cracking (1-C), 2) single-step simultaneous cracking, and hydrotreatment (1-C·H), and 3) a two-step process of cracking followed by hydrotreatment (2-C·H). Reaction products were characterized using different instruments and metrics: GC-FID, GC–MS, simulated distillation, CHNS-O elemental analyzer, viscometer, higher heating value (HHV), and total acid number (TAN). The 2-C·H process produced the highest amounts of desired hydrocarbons. The highest liquid yield of 81% with HHV of 47 MJ/kg was obtained with the use of Ni/SiO2-Al2O3 catalyst. All catalysts appeared to be regenerable after partial deactivation. Model compound studies were performed using erucic acid that accounted for about 40% of carinata oil FFA (free fatty acid) profile. Reaction pathways were proposed according to the chemical analysis of the products.

Drying Oil and Natural Varnishes in Paintings: A Competition in the Metal Soap Formation

Metal soaps formation is a well-known issue in oil paintings. Along the lifetime of the painting, carboxylic acids coming from drying oil (free fatty acids, acids from hydrolysis of triglycerides and from oxidation processes) can react with cations of some pigments (in particular, smalt, lead white and zinc white) forming the related carboxylic salts. As observed by many authors, the formation of these carboxylates, with the tendency to migrate and to aggregate, not only modifies the behavior and the aspect of the paint film but also complicates the cleaning approach. In previous works we have demonstrated that a similar pigment reactivity is possible even in presence of natural resins (such as colophony, dammar, mastic, etc) historically used as final varnishes on paintings. In this case, in the reactions the terpenic acids, among the main components of the resins, are involved. In this work, the carboxylates formation kinetics has been studied starting from two representative acids (palmitic and abietic) of painting oils and natural varnishes. Successively, the reactivity of the palmitic acid with the potassium abietate and of the abietic acid with the potassium palmitate has been verified. This investigation aims at clarifying in which way terpenic acids can be involved in the metal soaps reactivity confirming that also surface varnishes may play a significant role in the carboxylates formation and reactivity. It is important to keep in mind that a finishing varnish can be removed and reapplied many times during the lifetime of a painting, thus renewing the provision of reactive terpenic acids at the interface of the painted layers.

Investigation of using egg shell powder for bleaching of soybean oil

Egg shell that accounts about 11% of egg weight is one of the industrial wastes that in this research has been used for soybean oil bleaching. The effects of using 1% and 2% of five different types of adsorbents; egg shell powder, egg shell ash, acid activated egg shell powder, acid activated egg shell ash and commercial bleaching earth have been investigated on the bleaching of neutralized soybean oil. The peroxide value, free fatty acid, chlorophyll, carotenoids, metals (copper and iron) and oil retention were determined. Egg shell structure was investigated. According to the results, the bulk of the egg shell consists of calcium and some other compounds such as magnesium, iron and manganese while silicate is the main composition of commercial bleaching earths. The results indicated that soybean oil bleaching with 2% egg shell powder reduced carotenoids and chlorophyll contents up to 82.56% and 46.33%, respectively. Also using of adsorbents based on egg shell reduced significantly (p < 0.05) the peroxide value, free fatty acid contents and oil retention as compared to commercial bleaching earth. It might be concluded that egg shell powder as an industrial waste can be employed as an adsorbent and regarded as a good alternative for bleaching of edible oils due to its high efficiency to remove undesirable components (pigments, iron, copper, oxidation products and free fatty acids) from neutralized oils and environmental protection against acid pollution.

Intensification and optimization of biodiesel production using microwave-assisted acid-organo catalyzed transesterification process

To produce biodiesel cost-effective, low-cost, high free fatty acid (FFA) oil feedstock is desirable. But high FFA creates difficulty during the base-catalyzed transesterification process by yield loss due to the formation of soap. However, these problems are overcome by the use of an acid catalyst. The acid catalysts can directly convert both triglycerides and FFAs into biodiesel without the formation of soaps or emulsions. The shortcomings of mostly used inorganic acids are that they work well for esterification of FFA present in low-cost oil, but their kinetics for transesterification of triglycerides present in oils is considerably slower. Corrosion of equipment is another major problem associated with an inorganic acid catalyst. The usage of an organic acid catalyst of the alkyl benzene sulfonic type, like 4-dodecyl benzene sulfonic acid (DBSA) minimizes these disadvantages of inorganic acid-catalyzed transesterification. The aim of the present investigation was to reduce the reaction time of transesterification of triglycerides further by using microwaves as a heating source in the presence of DBSA catalyst to achieve higher conversions under mild operating conditions. To optimize the transesterification variables for the higher conversion of biodiesel, the response surface methodology was employed to design the experiment. By using the DBSA catalyst under microwave heating at a temperature of 76 °C, conversion close to 100% in only 30 min of reaction time was obtained using a 0.09 molar ratio of catalyst to oil and 9.0 molar ratio of methanol to oil. A modified polynomial model was developed and was adequately fitted with the experimental data and could be used for understanding the effect of various process parameters. The catalyst to oil molar ratio and reaction temperature created a stronger effect on the biodiesel production than that exhibited by the methanol to oil molar ratio. It was observed that the microwave heating process outperformed conventional heating, providing a rapid, easy method for biodiesel synthesis from triglycerides in the presence of DBSA, an organic acid catalyst. The produced biodiesel was of good quality, as all the properties were within the prescribed limits of the ASTM D6751 standard.

Biofuels production from rubber seeds

Worldwide biodiesel is being produced mainly from edible and non-edible vegetable oils. The choice of vegetable oils depends on primarily on availability, price, and the policy adopted by governing agencies. Currently, rubber seed getting attention for production of biofuels. In this study, the entire work was carried out in this research in into three major parts; (1) Parameter optimization during rubber seed oil (RSO) extraction: The effects of process parameters such as extraction time (3–12 h), kernel particle size range (0.5–3 mm), ratio of kernel to solvent (0.03–0.09 g/ml), and variety of solvents (polar and non-polar) on sox let extraction process were studied. Design of experiment (DOE) schemes was considered to prepare an experimental matrix using central composite design (CCD) approach. Response surface methodology (RSM) was applied to optimize the process parameters to achieve maximum oil yield. (2) Ultrasonic-assisted chemical modification of RSO for rubber oil methyl ester (ROME) production: Since RSO is high free fatty acid oil, a two-step procedure, esterification using homogeneous catalyst followed by transesterification with heterogeneous catalyst was followed for ROME synthesis. Further, the physico-chemical properties and rheological behavior of rubber seed oil (RSO) and its derivative methyl esters as well as their blends with diesel fuel were investigated. (3) Solid by-product utilization for biofuel synthesis: Solid wastes generated during biodiesel feedstock preparation process which comprise 40–48 wt. % rubber seed shell (RSS) and 25–30 wt% rubber seed cake (RSC) were utilized to produce liquid fuel and bio-char. Physico-chemical properties and thermo-gravimetric analysis (TGA) based non-isothermal decomposition (pyrolysis) kinetics of RSS and RSC were investigated. In depth analysis of physico-chemical-thermal properties of RSS and RSC obtained products (liquid and bio-char) using various analytical techniques suggested that both RSS and RSC can be considered as a suitable feedstock for the production of value added chemicals including fuel.

Production and Characterization of Biodiesel from Aphanamixis polystachya Seed Oil

The present study focuses on the utilization of non-edible Aphanamixis polystachya seed oil as a potential feedstock for the production of biodiesel. The extracted oil from non-edible seed could not be directly exploited for biodiesel production owing to its high free fatty acid (FFA) content of 5.785%, so acid catalyzed esterification was applied to reduce FFA of oil to zero followed by base-catalyzed transesterification to convert esterified product to its mono-esters. Thermogravimetric analysis (TGA) revealed that the mass percentage corresponding to biodiesel under optimum conditions was 74.38%. The conversion of the triglycerides in the oil into biodiesel through transesterification was confirmed using FT-IR spectroscopy. The elemental analysis of the produced biodiesel was studied. The produced biodiesel had properties which were comparable with biodiesel standards and could be utilized as an alternative diesel fuel without any hardware modifications.&#x0D; Dhaka Univ. J. Sci. 68(2): 129-136, 2020 (July)

Enzymatic hydrolysis of farmed Atlantic salmon by-products: Investigation of operational parameters on extracted oil yield and quality

Six operational parameters (fish part, antioxidant addition, water addition, enzyme species, enzyme concentration and hydrolysis time) were studied for their effect on yield and quality of enzymatically extracted oil from farmed Atlantic salmon by-products. The highest oil yield of 26.0% (93.6% recovery) was obtained from salmon viscera using 1% Flavourzyme for 2 h without addition of water or the antioxidant. Averagely, salmon viscera produced more oil compared to mixture of salmon heads and frames. However, viscera oil had higher levels of oxidation and hydrolysis, indicating inferior quality. The use of Alcalase resulted in the highest oil quality compared to Flavourzyme and SEBPro, due to less oil oxidation and free fatty acids in the alkaline environment using Alcalase (pH 8). The enzyme concentration studied (0.1 and 1%) didn’t have any significant effect on oil yield or oxidation. At 1% enzyme concentration, the oil extracted from 4 h hydrolysis had higher levels of oxidation but lower level of free fatty acids compared to the oil extracted from 2 h hydrolysis. Addition of water significantly decreased both oil yield and quality. The use of antioxidant (0.15%) didn’t affect oil yield but significantly inhibited oil oxidation.