scholarly journals Use of Echium oil fatty acids and tricaprylin as substrates of enzymatic interesterification for the production of structured lipids

2018 ◽  
Vol 69 (1) ◽  
pp. 236 ◽  
Author(s):  
A. Yüksel ◽  
N. Şahin-Yeşilçubuk

Structured lipids (SLs) were produced from the free fatty acids of Echium oil and tricaprylin by enzymatic acidolysis reactions. Lipozyme® RM IM, immobilized sn-1,3 specific lipase was used in the enzymatic reactions. In order to optimize the incorporation of stearidonic acid (SDA), three factors were chosen [Reaction temperature (50-60 ºC), reaction time (6-12 hour) and substrate molar ratio (3-6 mol/mol (total free fatty acids/tricaprylin)] for the application of response surface methodology (RSM) using a central composite circumscribed design (CCC) with five levels. The optimum temperature, time and substrate molar ratio obtained from the models were 60 ºC; 6 h, 6 mol/mol, respectively. Furthermore, SLs with 6.2% SDA content at sn-2 position were produced by scaling up the process. SL was obtained with nearly 78-79% of long-chain fatty acids at the sn-2 position. According to the melting profile analysis, the melting peaks of tricaprylin and Echium oil were sharper and narrower while the SL had more broadened peaks.

Author(s):  
Vijaya Lakshmi Ch ◽  
Uday Bhaskar R.V.S ◽  
Viswanath Kotra ◽  
Satyavathi Bankupalli

Biodiesel from clean oils is comparatively easier than production from crude and non-edible oils. To achieve maximum yield of biodiesel, a two stage process is adopted in which non-edible oils are used as feed-stock: an acid catalyzed esterification of free fatty acids followed by base catalyzed transesterification. Presence of water formed during esterification reaction is detrimental to a viable transesterification process. In the present work, an alternate method for removal of water by in situ hydrolysis reaction of methyl acetate is introduced. The dehydration using methyl acetate during esterification has yielded good results as the soap formed during transesterification was minimal. The results indicated high conversion of triglycerides to methyl ester for lower oil to methanol ratio and at a lower temperature. For 1:3 molar ratio of oil to methanol, the conversion obtained was less than 90 percent and is equivalent to conversions with higher alcohol ratios during esterification in the absence of methyl acetate. These results are indicative of the fact that use of methyl acetate reduces the alcohol to oil ratio without affecting the conversions. Moreover, higher conversions are possible at lower temperatures in the presence of methyl acetate. It is further observed that the oils that are subjected to free fatty acid conversions in the presence of methyl acetate record very little soap formation during the transesterification reactions, thereby resulting in higher grade of biodiesel.


Author(s):  
D Fraser Davidson

Some of the initial biochemical findings, obtained from 141 randomly-selected cases of acute hyperglycaemia (admission plasma glucose >20 mmol/L) were examined. When viewed in terms of their initial plasma bicarbonate concentration, three groups were identifiable. Plasma concentrations of free fatty acids (FFA), acetone and the sum of 3-hydroxybutyrate (3OHB) and lactate were different between these groups. However, there were no differences in plasma glucose or lactate concentrations. It was further observed that the relationship between the plasma FFA/albumin molar ratio, and ketone concentration could be described by a rectangular hyperbola, and the initial anion gap was linearly related to the sum of the 3OHB and lactate concentrations.


2008 ◽  
Vol 101 (5) ◽  
pp. 709-715 ◽  
Author(s):  
Soressa M. Kitessa ◽  
Paul Young

α-Linolenic acid (ALA; 18 : 3n-3) and stearidonic acid (SDA; 18 : 4n-3) are on the biosynthetic pathway of EPA (20 : 5n-3) and DHA (22 : 6n-3). The n-3 fatty acid in rapeseed oil is ALA while Echium oil contains both ALA and SDA. To determine the comparative efficacy of ALA- and SDA-rich oils in enriching broiler meat with n-3 PUFA, we offered diets supplemented with rapeseed oil (rapeseed group) or Echium oil (Echium group) for 35 d to two groups of chicks (age 21 d). There were no differences in carcass weight (2·20 (sem 0·06) v. 2·23 (sem 0·05) kg), boned, skinless thigh muscle (494 (sem 20·5) v. 507 (sem 16·7) g), boned, skinless breast muscle (553 (sem 13·4) v. 546 (sem 11·6) g) or organ weights (heart, liver and gizzard) between the two groups. The total intramuscular fat (IMF) percentage of thigh (8·0 (sem 0·64) v. 8·1 (sem 0·62) %) and breast muscles (2·3 (sem 0·24) v. 2·0 (sem 0·19) %) were also similar between the groups. In contrast, the concentrations of most of the individual n-3 fatty acids (ALA, SDA, EPA and docosapentaenoic acid) were all higher in the Echium than the rapeseed group (P < 0·05). However, differences in DHA concentrations were significant in breast but not thigh muscle IMF. The total n-3 yields/100 g serve thigh muscle were 265 and 676 mg for the rapeseed and Echium groups, respectively (P < 0·0001). The corresponding values for equivalent breast muscles were 70 and 137 mg, respectively (P < 0·01). We conclude that Echium oil is a better lipid supplement than rapeseed oil in changing the concentration and yield of n-3 fatty acids, except DHA, in broiler meat.


1987 ◽  
Vol 33 (8) ◽  
pp. 1382-1386 ◽  
Author(s):  
K Liewendahl ◽  
S Tikanoja ◽  
H Mähönen ◽  
T Helenius ◽  
M Välimäki ◽  
...  

Abstract The mean concentration of free thyroxin (FT4) in serum, as determined by direct equilibrium dialysis, was decreased in patients with chronic renal failure (CRF) and increased in patients with various other nonthyroidal illnesses (NTI). The mean concentration of dialyzable free triiodothyronine (FT3) in serum was equally low in both groups of patients. Patients with CRF of various etiology but a similar degree of renal failure as estimated from serum creatinine assay had very similar concentrations of FT4 and FT3 in their serum. Mean thyroxin (T4) and triiodothyronine (T3) concentrations in serum were decreased in CRF and NTI, whereas the mean reverse-T3 concentration in serum was normal in CRF and increased in NTI. T4-binding globulin and albumin were markedly decreased in CRF and NTI; T4-binding prealbumin was increased in CRF and decreased in NTI. The mean concentration of nonesterified free fatty acids (FFA) in serum was increased in NTI but not in CRF. The weak, but significant, positive correlation observed between FT4 and FFA in serum (r = 0.34, P less than 0.01) in NTI indicates that the increase in serum FT4 in this group of patients could be an effect, at least in part, of FFA competing with T4 for binding sites on serum proteins. The stronger correlation detected between the serum FT4 concentration and the FFA/albumin molar ratio in serum (r = 0.60, P less than 0.001) demonstrates the importance of a low albumin concentration for expression of the effect of FFA on FT4 in severe systemic illnesses.


1978 ◽  
Vol 76 (2) ◽  
pp. 333-346 ◽  
Author(s):  
J. S. TINDAL ◽  
G. S. KNAGGS ◽  
I. C. HART ◽  
LAURA A. BLAKE

Recording electrodes were implanted in contact with the dura mater overlying the parietal cortex of six female goats, four of which were lactating. After recovery from surgery and complete familiarization with the housing conditions, the personnel and the recording technique, each goat was observed continuously for 24 h with simultaneous recording of the cortical electroencephalogram (EEG). Remote blood sampling was carried out every 30 min without disturbing the animal. Apart from the release of growth hormone (GH) associated with morning milking in two of the goats, there was no consistent relationship between the apparently spontaneous, episodic release of GH and behaviour, stages of sleep, cortical EEG, air temperature, time of day or night, obvious environmental stimuli which arose from the normal husbandry routine, or the levels of prolactin, insulin, glucose or free fatty acids in the blood. There was also no relationship between the release of prolactin and the stages of sleep.


Blood ◽  
1971 ◽  
Vol 38 (1) ◽  
pp. 27-38 ◽  
Author(s):  
MINORU OKUMA ◽  
MANFRED STEINER ◽  
MARIO BALDINI

Abstract Lipid content and capacity to incorporate in vitro palmitate-1-14C and linoleate-1-14C into lipids was investigated in fresh and stored (4°C) human platelets. Cholesterol and phospholipids decreased 30% during storage for 6 days. Molar ratio of cholesterol to phospholipids and percentage distribution of individual phospholipids were similar in fresh and stored platelets. Palmitate bound to albumin was rapidly transferred by an energy-independent mechanism into a free fatty acid fraction of platelets. From there it was incorporated into glycerides and phospholipids, a process requiring energy. More palmitate than linoleate was incorporated into fatty acids and glycerides of fresh and stored platelets but linoleate exceeded palmitate in its incorporation into phosphatidylethanolamine. Storage of platelets produced the following changes: (1) Incorporation of palmitate into total lipids was significantly reduced but not that of linoleate. (2) Both palmitate and linoleate showed increased incorporation into phosphatidylethanolamine. (3) Incorporation of linoleate into free fatty acids and triglycerides and of palmitate into phosphatidylcholine was reduced.


Author(s):  
Elsy Arenas ◽  
Aidin Urribarrí ◽  
John Sánchez ◽  
Marisela Rincón ◽  
Karina Martínez ◽  
...  

Large quantities of used vegetable oils (AVUs) are generated annually, as a result of food preparation, which can cause contamination of waters and soils, if they are not disposed of properly, but in turn have great potential in the production of biodiesel. In this work, the AVU collected from fast food establishments were subjected to an esterification pretreatment, varying the reaction conditions, molar ratio, catalyst concentration and time, to decrease the content of free fatty acids generated in the frying processes; after an alkaline transesterification. The initial acidity of the AVUs (10,08 ± 0,22 %) was found to drop below 1 % during esterification at 60 °C and 100 rpm, with RMAVU:MeOH of 1: 7 and HCl concentration of 0.3 % v/v, with a conversion of free fatty acids (FFA) to methyl esters of 94.48 and 98.61 % for reaction times of 4 and 6 hours, respectively. The previously esterified AVUs were subjected to a transesterification process with KOH as a catalyst in the presence of methanol, at 60 °C and 100 rpm, finding that the biodiesel produced was a mixture composed of the methyl esters of linoleic acids (57 %), palmitic (14 %), oleic (22 %), stearic (4 %) and elaidic (3 %). The highest concentration of methyl esters (93,797 ± 0.685 g.L-1) was obtained when using the esterified AVU during 6 hours of reaction. FTIR spectra confirmed the conversion of fatty acids to methyl esters, so this product could be used as a biofuel.


Molecules ◽  
2015 ◽  
Vol 20 (7) ◽  
pp. 12328-12340 ◽  
Author(s):  
Nur Azeman ◽  
Nor Yusof ◽  
Jaafar Abdullah ◽  
Robiah Yunus ◽  
Mohd Hamidon ◽  
...  

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