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1.
Oil palm (E. guineensis) fruits at three stages of development were studied. At week 12–13 after anthesis, the endosperm had started accumulating
oil and tissue slices incorporated [1-14C] acetate into fatty acids which resembled those found in the mature endosperm. The mesocarp contained very little oil and
incorporated acetate into polar lipids. At week 16–17, the mesocarp started to accumulate oil; this was reflected in the [14C] lipid products from acetate incubation. At or just prior to this stage, an increase in the endogenous linoleic and linolenic
acid content and the increase in fruit size indicated cellular growth in the mesocarp tissue. At week 20–21 the fruit was
ripe, and both endosperm and mesocarp tissues were filled with storage oil. [14C] Fatty acids synthesized from acetate by mesocarp slices at this stage were the same as the endogenous storage fatty acids
in bothE. guineensis andE. oleifera. A very weak fatty acid synthesizing activity was seen in the mature endosperm, but the products had no relationship to the
storage lipid. 相似文献
2.
B. K. Tan S. H. Ong N. Rajanaidu V. Rao 《Journal of the American Oil Chemists' Society》1985,62(2):230-236
Prospects for modification of palm oil composition through oil palm breeding, tissue culture and enzyme-catalyzed transesterification
are reviewed. Present emphasis in oil modification is toward greater unsaturation. The greatest prospect for this area lies
in the interspecific hybridization ofE. oleifera andE. guineensis. The target recommended is for a hybrid oil of iodine value above 72 having a palmitic acid content below 25% and an oleic
acid content above 60%. It is noted that the variability of linoleic acid in the oil palm is limited regardless of species.
The greatest contribution towards unsaturation, therefore, lies mainly in oleic acid. Tissue culture is seen as a potential
propagating tool for selecting progenies of important crosses from the hybridization ofE. oleifera andE. guineensis, while enzyme-catalyzed transesterification using a 1,3 specific lipase offers the possibility of enhancing the level of
linoleic acid in palm oil. Besides breeding for unsaturation, production of palms giving oils of specific fatty acid or triglyceride
types also may be possible ultimately. 相似文献
3.
C. Mohankumar C. Arumughan R. Kaleysa raj 《Journal of the American Oil Chemists' Society》1990,67(10):665-669
Development of free fatty acids (FFA) and subsequent deterioration of palm oil quality can be attributed to lipase, an active
hydrolytic enzyme present in the mesocarp of oil palm fruit. A histochemical method was used to localize this enzyme in the
mesocarp. FFA released from endogenous glycerides were precipitated as lead salt. The deposits were located on the membranes
of oil bodies. Enzymatic activity in the mesocarp was also studied under different conditions of fruit storage: ambient temperature,
freezing, etc. The enzyme was active after freezing but less active under ambient conditions of fruit storage. Investigations
on fruit development indicated that the enzyme activity started appearing between 16–20 weeks after anthesis (WAA) which synchronized
with the beginnning of lipid formation. These histochemical studies were supported wity biochemical data on FFA. 相似文献
4.
Gerald P. McNeill Philip E. Sonnet 《Journal of the American Oil Chemists' Society》1995,72(2):213-218
Three lipases were compared for their ability to hydrolyze high erucic acid rapeseed oil, with the objective of concentrating
the erucic acid in a single glyceride fraction. Lipase fromPseudomonas cepacia released all fatty acids rapidly and did not result in selective distribution of erucic acid.Geotrichum candidum lipase released C20 and C22 fatty acids extremely slowly, resulting in their accumulation in the di- and triglyceride fractions.
Less than 2% of the total erucic acid was found in the free fatty acid (FFA) fraction. Lipase fromCandida rugosa released erucic acid more slowly than C20 and C18 fatty acids at 35°C but only resulted in a limited accumulation of the
erucic acid in the di- and triglyceride fractions. However, when hydrolysis catalyzed byC. rugosa lipase was carried out below 20°C, the reaction mixture solidified and was composed solely of FFAs and diglycerides. The
diglyceride fraction contained approximately 95% erucic acid while about 20% of the total erucic acid was found in the FFA
fraction. It is concluded that hydrolysis at low temperature withC. rugosa lipase results in a higher purity of erucic acid in the glyceride fraction than can be obtained withG. candidum lipase, but with considerable loss of erucic acid to the FFA fraction. 相似文献
5.
Crude Palm Oil from Interspecific Hybrid Elaeis oleifera × E. guineensis: Alcoholic Constituents of Unsaponifiable Matter 下载免费PDF全文
Massimo Mozzon Deborah Pacetti Natale Giuseppe Frega Paolo Lucci 《Journal of the American Oil Chemists' Society》2015,92(5):717-724
Interspecific hybrid Elaeis oleifera × E. guineensis (O×G) palm is currently receiving increasing attention because of its interesting glycerides structure and composition. In this study, the alcoholic constituents of unsaponifiable matter of crude hybrid O×G palm oil were characterized for the first time and compared to data obtained analyzing crude African palm oil (E. guineensis).Total unsaponifiable matter content was 1.18 ± 0.11 g/100 g in O×G hybrid oil and 1.05 ± 0.06 g/100 g in African palm oil. O×G oil was characterized by lower contents of squalene and alcoholic constituents where the main differences concerned 4‐desmethylsterols and isoprenoid alcohols: O×G oil was characterized by higher (23.6 ± 6.1 %) contents of isoprenoid alcohols and by a different phytol/geranylgeraniol ratio. The tocol fraction constituted the class of unsaponifiable components on which the genetic exerts the greatest influence: tocol content showed no significant differences between the two oils, however, hybrid palm oil was characterized by higher percentages of γ‐tocotrienol (59.7 ± 1.1) and δ‐tocotrienol (11.7 ± 0.8) and lower percentages of tocopherols (10.6 ± 0.3), almost entirely constituted of the α isomer. These results suggest that O×G oil can also be considered an interesting alimentary source of nutraceutical components, especially for bioactive tocotrienols. 相似文献
6.
Yew Ai Tan Kum Wan Low Chak Khiam Lee Kum Sang Low 《European Journal of Lipid Science and Technology》2010,112(8):838-843
We investigated a non‐destructive technique for measuring the colour of oil palm fruit (Elaeis guineensis) bunches at different stages of maturity and correlating the colour data with the oil content in the fruit bunch. A digital red, green and blue (RGB) camera was used to capture the image of palm fruits and hue histograms were then constructed from mathematically transformed RGB data. The dominant hue peaks were then correlated to the oil content of fresh fruit bunches (FFBs). The study showed that the results obtained were influenced by FFB that possessed different expressions of colour changes during the ripening process. The results obtained from colour image analyses were not satisfactory – the correlation between hue peak and FFB oil content was r = 0.7933. However, when FFB having the same ripening patterns were analysed, the correlation was very much improved with r = 0.9519. Thus, statistical evaluation showed that the digital imaging technique for determining FFB oil content can be successfully used on a homogeneous population of palms that display similar change of colour during the ripening process. Practical applications : The ability to correctly identify physiological maturity and harvest maturity of palm fruits by phenological characteristics will ensure timely harvest to avoid cutting of either under‐ and over‐ripe fruits. The Malaysian Palm Oil Board [MPOB] 1 has published an oil palm fruit grading manual outlining 16 classifications for grading FFB ripeness and quality. However, the FFB grading methods are still very subjective, i.e. depend on the judgement, experience and skill of a person. In addition, the methods do not provide quantitative information about the oil in the FFB. The method reported in this paper allows for rapid screening of FFB ripeness, and relate it to oil content in the FFB and accordingly the amount of oil that can be extracted from a consignment of FFB. Since it only takes a few seconds to capture signals, the system could be incorporated for on‐line monitoring of FFB ripeness and oil content thereof. 相似文献
7.
Betty Mbatia Bo Mattiasson Francis Mulaa Patrick Adlercreutz 《European Journal of Lipid Science and Technology》2011,113(6):717-723
PUFA from oil extracted from Nile perch viscera were enriched by selective enzymatic esterification of the free fatty acids (FFA) or by hydrolysis of ethyl esters of the fatty acids from the oil (FA‐EE). Quantitative analysis was performed using RP‐HPLC coupled to an evaporative light scattering detector (RP‐HPLC‐ELSD). The lipase from Thermomyces lanuginosus discriminated against docosahexaenoic acid (DHA) most, resulting in the highest DHA/DHA‐EE enrichment while lipase from Pseudomonas cepacia discriminated against eicosapentaenoic acid (EPA) most, resulting in the highest EPA/EPA‐EE enrichment. The lipases discriminated between DHA and EPA with a higher selectivity when present as ethyl esters (EE) than when in FFA form. Thus when DHA/EPA were enriched to the same level during esterification and hydrolysis reactions, the DHA‐EE/EPA‐EE recoveries were higher than those of DHA/EPA‐FFA. In reactions catalysed by lipase from T. lanuginosus, at 26 mol% DHA/DHA‐EE, DHA recovery was 76% while that of DHA‐EE was 84%. In reactions catalysed by lipase from P. cepacia, at 11 mol% EPA/EPA‐EE, EPA recovery was 79% while that of EPA‐EE was 92%. Both esterification of FFA and hydrolysis of FA‐EE were more effective for enriching PUFA compared to hydrolysis of the natural oil and are thus attractive process alternatives for the production of products highly enriched in DHA and/or EPA. When there is only one fatty acid residue in each substrate molecule, the full fatty acid selectivity of the lipase can be expressed, which is not the case with triglycerides as substrates. 相似文献
8.
Sirirung Wongsakul Poonsuk Prasertsan Uwe T. Bornscheuer Aran H‐Kittikun 《European Journal of Lipid Science and Technology》2003,105(2):68-73
Commercial immobilized lipases were used for the synthesis of 2‐monoglycerides (2‐MG) by alcoholysis of palm and tuna oils with ethanol in organic solvents. Several parameters were studied, i.e., the type of immobilized lipases, water activity, type of solvents and temperatures. The optimum conditions for alcoholysis of tuna oil were at a water activity of 0.43 and a temperature of 60 °C in methyl‐tert‐butyl ether for ~12 h. Although immobilized lipase preparations from Pseudomonas sp. and Candida antarctica fraction B are not 1, 3‐regiospecific enzymes, they were considered to be more suitable for the production of 2‐MG by the alcoholysis of tuna oil than the 1, 3‐regiospecific lipases (Lipozyme RM IM from Rhizomucor miehei and lipase D from Rhizopus delemar). With Pseudomonas sp. lipase a yield of up to 81% 2‐MG containing 80% PUFA (poly‐unsaturated fatty acids) from tuna oil was achieved. The optimum conditions for alcoholysis of palm oil were similar as these of tuna oil alcoholysis. However, lipase D immobilized on Accurel EP100 was used as catalyst at 40 °C with shorter reaction times (<12 h). This lead to a yield of ~60% 2‐MG containing 55.0‐55.7% oleic acid and 18.7‐21.0% linoleic acid. 相似文献
9.
Jamshid Farmani Mohammad Safari Manouchehr Hamedi 《European Journal of Lipid Science and Technology》2009,111(12):1212-1220
Binary blends of canola oil (CO) and palm olein (POo) or fully hydrogenated soybean oil (FHSBO) were interesterified using commercial lipase, Lypozyme TL IM, or sodium methoxide. Free fatty acids (FFA) and soap content increased and peroxide value (PV) decreased after enzymatic or chemical interesterification. No difference was observed between the PV of enzymatically and chemically interesterified blends. Enzymatically interesterified fats contained higher FFA and lower soap content than chemically prepared fats. Slip melting point (SMP) and solid‐fat content (SFC) of CO and POo blends increased, whereas those of CO and FHSBO blends decreased after chemical or enzymatic interesterification. Enzymatically interesterified CO and POo blends had lower SMP and SFC (at some temperatures) than chemically interesterified blends. The status was reverse when comparing chemically and enzymatically interesterified CO and FHSBO blends. The induction period for oxidation at 120°C of blends decreased after interesterification. However, chemically interesterified blends were more oxidatively stable than enzymatically interesterified blends. Interesterified blends of CO and POo or FHSBO displayed characteristics suited to application as trans‐free soft tub, stick, roll‐in and baker's margarine, cake shortening and vanaspati fat. 相似文献
10.
Yomi Watanabe Toshihiro Nagao Yutaka Nishida Yoshiaki Takagi Yuji Shimada 《Journal of the American Oil Chemists' Society》2007,84(11):1015-1021
Acid oil, a by-product of vegetable oil refining, was enzymatically converted to fatty acid methyl esters (FAME). Acid oil
contained free fatty acids (FFA), acylglycerols, and lipophilic compounds. First, acylglycerols (11 wt%) were hydrolyzed at
30 °C by 20 units Candida rugosa lipase/g-mixture with 40 wt% water. The resulting oil layer containing 92 wt% FFA was used for the next reaction, methyl
esterification of FFA to FAME by immobilized Candida antarctica lipase. A mixture of 66 wt% oil layer and 34 wt% methanol (5 mol for FFA) were shaken at 30 °C with 1.0 wt% lipase. The degree
of esterification reached 96% after 24 h. The resulting reaction mixture was then dehydrated and subjected to the second esterification
that was conducted with 2.2 wt% methanol (5 mol for residual FFA) and 1.0 wt% immobilized lipase. The degree of esterification
of residual FFA reached 44%. The degree increased successfully to 72% (total degree of esterification 99%) by conducting the
reaction in the presence of 10 wt% glycerol, because water in the oil layer was attracted to the glycerol layer. Over 98%
of total esterification was maintained, even though the first and the second esterification reactions were repeated every
24 h for 40 days. The enzymatic process comprising hydrolysis and methyl esterification produced an oil containing 91 wt%
FAME, 1 wt% FFA, 1 wt% acylglycerols, and 7 wt% lipophilic compounds. 相似文献
11.
B. K. De 《Journal of the American Oil Chemists' Society》2006,83(5):443-448
The purpose of this study was to investigate enzymatic and autocatalytic esterification of FFA in rice bran oil (RBO), palm
oil (PO), and palm kernel oil (PKO), using MG and DG as esterifying agents. The reactions were carried out at low pressure
(4–6 mm Hg) either in the absence of any added catalyst at high temperature (210–230°C) or in the presence of Mucor miehei lipase at low temperature (60°C). The reactions were carried out using different concentrations of MG, and the optimal FFA/MG
ratio and time were 2∶1 (molar) and 6 h, respectively, in both auto- and enzyme-catalyzed processes. With DG as the esterifying
agent in the autocatalytic process, the optimal temperature was 220°C, and the optimal FFA/DG ratio was 1∶1.25. For both MG
and DG, the enzymatic process was more effective in reducing FFA and produced more favorable levels of unsaponifiable matter
and color in the final product. The PV of the final products were also lower (1.8–2.9 mequiv/kg) by using the enzymatic process.
To produce edible-grade oil, a single deodorization step would be required after enzymatic esterification; whereas, alkali
refining, bleaching, and deodorization would be required after autocatalytic treatment. 相似文献
12.
Determination of free fatty acids in palm oil by near-infrared reflectance spectroscopy 总被引:9,自引:4,他引:5
A near-infrared (NIR) spectroscopy calibration was developed for the determination of free fatty acids (FFA) in crude palm
oil and its fractions based on the NIR reflectance approach. A range of FFA concentrations was prepared by hydrolyzing oil
with 0.15% (w/w) lipase in an incubator at 60°C (200 rpm). Sample preparation was performed in Dutch cup, and the spectra
were measured in duplicate for each sample. The optimized calibration models were constructed with multiple linear regression
analysis based on C=O overtone regions from 1850–2050 nm. The best wavelength combinations were 1882, 2010, and 2040 nm. Multiple
correlation coefficients squared (R
2) were: 0.994 for crude palm oil, 0.961 for refined-bleached-deodorized (RBD) palm olein, and 0.971 for RBD palm oil. Calibrations
were validated with an independent set of 8–10 samples. R
2 of validation were 0.997, 0.943, and 0.945, respectively. The developed method was rapid, with a total analysis time of 5
min, and environmentally friendly, and its accuracy was generally good for raw-material quality control. 相似文献
13.
Purification of docosahexaenoic acid from tuna oil by a two-step enzymatic method: Hydrolysis and selective esterification 总被引:3,自引:0,他引:3
Yuji Shimada Kazuaki Maruyama Akio Sugihara Shigeru Moriyama Yoshio Tominaga 《Journal of the American Oil Chemists' Society》1997,74(11):1441-1446
Purification of docosahexaenoic acid (DHA) was attempted by a two-step enzymatic method that consisted of hydrolysis of tuna
oil and selective esterification of the resulting free fatty acids (FFA). When more than 60% of tuna oil was hydrolyzed with
Pseudomonas sp. lipase (Lipase-AK), the DHA content in the FFA fraction coincided with its content in the original tuna oil. This lipase
showed stronger activity on the DHA ester than on the eicosapentaenoic acid ester and was suitable for preparation of FFA
rich in DHA. When a mixture of 2.5 g tuna oil, 2.5 g water, and 500 units (U) of Lipase-AK per 1 g of the reaction mixture
was stirred at 40°C for 48 h, 83% of DHA in tuna oil was recovered in the FFA fraction at 79% hydrolysis. These fatty acids
were named tuna-FFA-Ps. Selective esterification was then conducted at 30°C for 20 h by stirring a mixture of 4.0 g of tuna-FFA-Ps/lauryl alcohol (1:2, mol/mol), 1.0 g water, and 1,000 U of Rhizopus delemar lipase. As a result, the DHA content in the unesterified FFA fraction could be raised from 24 to 72 wt% in an 83% yield.
To elevate the DHA content further, the FFA were extracted from the reaction mixture with n-hexane and esterified again under the same conditions. The DHA content was raised to 91 wt% in 88% yield by the repeated
esterification. Because selective esterification of fatty acids with lauryl alcohol proceeded most efficiently in a mixture
that contained 20% water, simultaneous reactions during the esterification were analyzed qualitatively. The fatty acid lauryl
esters (L-FA) generated by the esterification were not hydrolyzed. In addition, L-FA were acidolyzed with linoleic acid, but
not with DHA. These results suggest that lauryl DHA was generated only by esterification. 相似文献
14.
Mohamed M. Soumanou Uwe T. Bornscheuer 《European Journal of Lipid Science and Technology》2003,105(11):656-660
Fatty acid alkyl esters were produced from various vegetable oils by transesterification with different alcohols using immobilized lipases. Using n‐hexane as organic solvent, all immobilized lipases tested were found to be active during methanolysis. Highest conversion (97%) was observed with Thermomyces lanuginosa lipase after 24 h. In contrast, this lipase was almost inactive in a solvent‐free reaction medium using methanol or 2‐propanol as alcohol substrates. This could be overcome by a three‐step addition of methanol, which works efficiently for a range of vegetable oils (e.g. cottonseed, peanut, sunflower, palm olein, coconut and palm kernel) using immobilized lipases from Pseudomonas fluorescens (AK lipase) and Rhizomucor miehei (RM lipase). Repeated batch reactions showed that Rhizomucor miehei lipase was very stable over 120 h. AK and RM lipases also showed acceptable conversion levels for cottonseed oil with ethanol, 1‐propanol, 1‐butanol and isobutanol (50‐65% conversion after 24 h) in solvent‐free conditions. Methyl and isopropyl fatty acid esters obtained by enzymatic alcoholysis of natural vegetable oils can find application in biodiesel fuels and cosmetics industry, respectively. 相似文献
15.
Roland D. Abigor Patrick O. Uadia Thomas A. Foglia Michael J. Haas Karen Scott Brett J. Savary 《Journal of the American Oil Chemists' Society》2002,79(11):1123-1126
Lipase present in the seeds of Jatropha curcas L. was isolated and some of its properties studied. Lipase activity was detected in both dormant and germinating seeds. The
lipase was partially purified using a combination of ammonium sulfate precipitation and ultrafiltration, which increased the
relative activity of the lipase by 28- and 80-fold, respectively. The lipase hydrolyzed palm kernel, coconut, and olive oils
at comparable rates (approximately 5 μg FFA/μg protein/min); palm—Raphia hookeri and Jatropha curcas L.—oils at about twice the rate of the first group of oils; and palm and fish oils at a higher rate than all other oils.
The lipase, however, had the highest activity with monoolein. Optimal pH and temperature for maximal lipase activity were
7.5 and 37°C, respectively. The addition of ferric ion (15 mM) to the lipase assay medium caused 90% inhibition of lipase
activity, whereas calcium and magnesium ions enhanced lipase activity by 130 and 30%, respectively. 相似文献
16.
Ecofriendly modification of acetosolv lignin from oil palm biomass for improvement of PMMA thermo‐oxidative properties 下载免费PDF全文
Davi Rabelo de Oliveira Izabel de Menezes Nogueira Francisco Jonas Nogueira Maia Morsyleide Freitas Rosa Selma Elaine Mazzetto Diego Lomonaco 《应用聚合物科学杂志》2017,134(46)
The environmentally friendly esterification of acetosolv lignin (AL), obtained from pressed oil palm mesocarp fibers, is described, for the improvement of thermo‐oxidative properties of poly(methyl methacrylate) (PMMA) films. Acetylation of AL was performed in ecofriendly conditions using acetic anhydride in the absence of catalysts. Acetylated acetosolv lignin (AAL) was successfully obtained in only 12 min with a solvent‐free and catalyst‐free microwave‐assisted procedure. Lignins were characterized by Fourier transform infrared spectroscopy, size exclusion chromatography, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC), confirming the efficacy of the methodology employed. AL and AAL as fillers in different concentrations (1% and 5%) were added to PMMA films. The thermal and mechanical properties of the lignin‐incorporated films were analyzed by TGA, DSC, and dynamic mechanical analysis (DMA). The films incorporated with lignin and acetylated lignin presented initial degradation temperature (Tonset) and onset oxidative temperature (OOT) values higher than pure PMMA films, contributing thus to an enhancement of thermo‐oxidative stability of PMMA. The DMA analyses showed that incorporation of AL or AAL increased the storage modulus (E′) of PMMA films, but did not affect their glass‐transition temperatures (Tg). The results indicate the potential use of oil palm mesocarp lignin to enhance the thermo‐oxidative properties of PMMA without compromising its mechanical response. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45498. 相似文献
17.
S. H. Ong C. C. Chuah H. P. Sow 《Journal of the American Oil Chemists' Society》1981,58(12):1032-1038
Determination of the fatty acid and triglyceride compositions of the F,(Elaeis guineensis X E. oleifera), F2 and the backcross hybrid mesocarp oils demonstrated that most fatty acid and triglyceride compositions of oils from hybrid
palms are intermediate between those of their respective parentals. These data, as well as the acyl group (saturated/palmitate
and unsaturated/oleate) distribution of triglycerides of the F2 mesocarp oils provide genetic proof for codominance in the F2 generation which shows a characteristic segregation into the co-dominance ratio of 1:2:1 (i.e., 1 E.guineensis: 2 F1 hybrid: 1E. oleifera). Similar analyses into the backcross hybrid mesocarp oils on the whole confirmed co-dominance when the backcross ratio of
1:1 was obtained. These results are used to develop the Co-Dominance Theory ofElaeis palm hybridization which makes successful predictions for mesocarp oils from the different hybrid palms. 相似文献
18.
The hydrolysis of palm oil, palm olein and palm stearin, soybean oil, corn oil and peanut oil by the commercial lipase fromCandida rugosa (formerly known asC. cylindracea) was studied. The optimal conditions for the hydrolysis of palm oil by the lipase were established. The lipase fromC. rugosa exhibits an optimal activity at 37 C and at pH 7.5. The optimal oil to hexane ratio is 1 g of oil to 0.5 ml hexane. The rate
of hydrolysis of palm oil by the lipase is linear on a logarithmic scale. Under the same conditions, palm oil and palm olein
were hydrolyzed at the same rate, whereas palm stearin was hydrolyzed much more slowly. 相似文献
19.
Separation of EPA and DHA in fish oil by lipase-catalyzed esterification with glycerol 总被引:4,自引:0,他引:4
The objective of this study was to investigate the use of lipases as catalysts for separating EPA and DHA in fish oil by kinetic
resolution based on their FA selectivity. Esterification of FFA from various types of fish oils with glycerol by immobilized
Rhizomucor miehei lipase under water-deficient, solvent-free conditions resulted in a highly efficient separation of EPA and DHA. Reactions
were conducted at 40°C with a 10% dosage of the lipase preparation under vacuum to remove the coproduced water, thus rapidly
shifting the reaction toward the products. The bulk of the FA, together with EPA, were converted into acylglycerols, whereas
DHA remained in the residual FFA. As an example, when FFA from tuna oil comprising 5% EPA and 25% DHA were esterified with
glycerol, 90% conversion into acylglycerols was obtained after 48 h. The residual FFA contained 78% DHA and only 3% EPA, in
79% DHA recovery. EPA recovery in the acylglycerol fraction was 91%. The type of fish oil and extent of conversion were highly
important parameters in controlling the degree of concentration. 相似文献
20.
The purification of tocopherols and phytosterols (referred to as sterols) from soybean oil deodorizer distillate (SODD) was
attempted. Tocopherols and sterols in the SODD were first recovered by short-path distillation, which was named sODD tocopherol/sterol
concentrate (SODDTSC). The SODD-TSC contained MAG, DAG, FFA, and unidentified hydrocarbons in addition to the two substances
of interest. It was then treated with Candida rugosa lipase to convert sterols to FA steryl esters, acylglycerols to FFA, and FFA to FAME. Methanol (MeOH), however, inhibited
esterification of the sterols. Hence, a two-step in situ reaction was conducted: SODDTSC was stirred with 20 wt% water and 200 U/g mixture of C. rugosa lipase at 30°C, and 2 moles of MeOH per mole of FFA was added to the reaction mixture after 16h. The lipase treatment for
40 h in total achieved 80% conversion of the initial sterols to FA steryl esters, complete hydrolysis of the acylglycerols,
and a 78% decrease in the initial FFA content by methyl esterification. Tocopherols did not change throughout the process.
To enhance the degree of steryl and methyl esterification, the reaction products, FA steryl esters and FAME, were removed
by short-path distillation, and the resulting fraction containing tocopherols, sterols, and FFA was treated with the lipase
again. Distillation of the reaction mixture purified tocopherols to 76.4% (recovery, 89.6%) and sterols to 97.2% as FA steryl
esters (recovery, 86.3%). 相似文献