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1.
Hans Kaunitz Charles A. Slanetz Ruth Ellen Johnson Vigen K. Babayan 《Journal of the American Oil Chemists' Society》1959,36(8):322-325
- Effects of medium-chain (C6–C12) saturated triglycerides (MCT) and long-chain (C14–C18) saturated triglycerides (LCT) with and without linoleic acid (LA) supplementation were studied on rats fed purified diets
- With 2% linoleic acid rats fed MCT and LCT grew somewhat better than those on a low-fat diet with the same supplement. Without linoleic acid those fed MCT grew better, and those fed LCT grew worse than those on the corresponding low-fat diet. MCT seemed to decrease, and LCT to increase linoleic acid requirements.
- In survival studies 14 out of 18 rats fed 20% MCT were alive after 2 years; of their controls fed 20% lard, 10 out of 19 survived.
- Reproduction studies in females gave equally poor results on unsupplemented low-fat, MCT, and LCT diets regarding implantation, birth weight, and survival rate. The weaning weights of the young on MCT were however the highest. With 2% LA weaning weights were equally high with LCT and MCT but lower with low-fat diet.
- In animals fed low-fat diets not supplemented with LA, low serum cholesterol was associated with high liver cholesterol. With MCT, serum values were higher and liver values were significantly lower. With unsupplemented LCT, serum and liver values were high. When the three diets were supplemented with 2% LA, there were no longer any differences in the serum levels and in the liver levels. Whether ar not the presence of some oleate in the MCT and LCT influenced the cholesterol results is not certain.
- The differences in the effects of MCT and LCT are discussed.
2.
Cardiolipins (CL) have unique fatty acid profiles with generally high levels of polyunsaturated fatty acids, primarily 18∶2n−6,
and low levels of saturated fatty acids. In order to study the effect of dietary fatty acid isomers on the fatty acid composition
of cardiolipins, rats were fed partially hydrogenated marine oils (HMO), rich in 16∶1, 18∶1, 20∶1, and 22∶1 isomeric fatty
acids, supplemented with linoleic acid at levels ranging from 1.9% to 14.5% of total fat. Although the dietary fats contained
33%trans fatty acids, the levels oftrans fatty acids in CL were below 2.5% in all organs. The fatty acid profiles of cardiolipins of liver, heart, kidney and testes
showed different responses to dietary linoleic acid level. In liver, the contents of 18∶2 reflected the dietary levels. In
heart and kidney, the levels of 18∶2 also parallelled increasing dietary levels, but in all groups fed HMO, levels of 18∶2
were considerably higher than in the reference group fed palm oil. In testes, the 18∶2 levels were unaffected by the dietary
level of 18∶2 and HMO. 相似文献
3.
The effect of subacute toxicity levels of dietary cyclopropenoid fatty acids upon several physiological parameters was determined in the rat. Diets containing 2% corn oil, 2%Sterculia foetida oil or 2% hydrogenatedSterculia foetida oil were fed.Sterculia foetida oil (50% cyclopropenoid fatty acids) fed rats exhibited retarded growth, elevated organ to body wt ratios, increased saturation of tissue lipid, and abnormal histopathology when compared to corn oil and hydrogenatedSterculia foetida oil fed rats. Growth was retarded 50%, liver/body wt doubled, and the percentage of saturated fatty acids in adipose tissue increased 2.5-fold forSterculia foetida oil vs. corn oil comparisons. Three membrane systems were examined in corn oil andSterculia foetida oil fed rats. Erythrocyte hemolysis rate in 0.3 M glycerol was increased by 30%; induction of mitochondrial swelling by reduced glutathione was inhibited completely and microsomal codeine demethylase activity was depressed nearly 50% inSterculia foetida oil fed rats. The ability of cyclopropenoid fatty acids to inhibit fatty acyl desaturase and influence tissue and membrane lipid composition is discussed. Most of the detrimental effects observed in cyclopropenoid fatty acids fed rats may be associated with alteration of normal lipid metabolism and membrane function. 相似文献
4.
Joanna K. Chan Bruce E. McDonald Jon M. Gerrard Vivian M. Bruce Bonnie J. Weaver Bruce J. Holub 《Lipids》1993,28(9):811-817
The effect of dietary α-linolenic acid (18∶3n−3) and its ratio to linoleic acid (18∶2n−6) on platelet and plasma phospholipid
(PL) fatty acid patterns and prostanoid production were studied in normolipidemic men. The study consisted of two 42-d phases.
Each was divided into a 6-d pre-experimental period, during which a mixed fat diet was fed, and two 18-d experimental periods,
during which a mixture of sunflower and olive oil [low 18∶3n−3 content, high 18∶2/18∶3 ratio (LO-HI diet)], soybean oil (intermediate
18∶3n−3 content, intermediate 18∶2/18∶3 ratio), canola oil (intermediate 18∶3n−3 content, low 18∶2/18∶3 ratio) and a mixture
of sunflower, olive and flax oil [high 18∶3n−3 content, low 18∶2/18∶3 ratio (HI-LO diet)] provided 77% of the fat (26% of
the energy) in the diet. The 18∶3n−3 content and the 18∶2/18∶3 ratio of the experimental diets were: 0.8%, 27.4; 6.5%, 6.9;
6.6%, 3.0; and 13.4%, 2.7, respectively. There were appreciable differences in the fatty acid composition of platelet and
plasma PLs. Nevertheless, 18∶1n−9, 18∶2n−6 and 18∶3n−3 levels in PL reflected the fatty acid composition of the diets, although
very little 18∶3n−3 was incorporated into PL. Both the level of 18∶3n−3 in the diet and the 18∶2/18∶3 ratio were important
in influencing the levels of longer chain n−3 fatty acid, especially 20∶5n−3, in platelet and plasma PL. Production of 6-keto-PGF1α was significantly (P<0.05) higher following the HI-LO diet than the LO-HI diet although dietary fat source had no effect on bleeding time or thromboxane
B2 production. The present study showed that both the level of 18∶3n−3 in the diet and its ratio to 18∶2n−6 were important in
influencing long-chain n−3 fatty acid levels in platelet and plasma PL and that prostanoid production coincided with the diet-induced
differences in PL fatty acid patterns. 相似文献
5.
A stereospecific distribution of fatty acids in bovine milk fat containing 15.5% linoleic acid has been compared with the
distribution in bovine milk fat containing a normal level (1.8%) of linoleic acid. The positional distribution was obtained
by the separate analysis of milk fat triglycerides of high, medium, and low molecular weight. The order of preference for
linoleic acid in the high molecular weight triglycerides was position 3>position 2 >position 1. There was an accompanying
altered distribution of myristic acid and palmitic acid in favor of position 1 at the expense of position 3. However, the
proportions of myristic acid and palmitic acid in position 2, relative to positions 1 and 3 were identifical in the high molecular
weight fractions of the two milk fats. The distribution of linoleic acid in the medium molecular weight triglycrides of linoleic-rich
milk fat was position 1=position 2>position 3. This resulted in a change in the distribution of 18 carbon monounsaturated
fatty acids in favor of position 2 at the expense of position 1, but the distribution of myristic acid and palmitic acid was
virtually unaltered. The distribution of linoleic acid in the low molecular weight triglycerides was position 2>position 1>position
3. The amounts of myristic acid and palmitic acid in position 2 and of palmitic acid in position 1 decreased in the low molecular
weight triglycerides of the milk fat containing elevated levels of linoleic acid. Changes in the distribution of fatty acids
which were observed in the separate analysis of the high, medium, and low molecular weight triglycerides were not apparent
when comparing the distribution in the total milk fats. For example, the distribution of myristic acid and palmitic acid appeared
to be unchanged, while the distribution of 18 carbon monounsaturated fatty acids was slightly altered in favor of positions
2 and 3. Moreover, linoleic acid showed an almost equal preference for the three positions of the glycerol moiety in milk
fat containing elevated levels of this fatty acid with some concentration at position 2. 相似文献
6.
Nutritional properties of the triglycerides of saturated fatty acids of medium chain-length 总被引:1,自引:0,他引:1
Hans Kaunitz Charles A. Slanetz Ruth Ellen Johnson Vigen K. Babayan George Barsky 《Journal of the American Oil Chemists' Society》1958,35(1):10-13
Summary The influence of a purified rat diet containing 20 or 33% of the saturated medium chain-length triglycerides (MCT) with and
without linoleic acid supplements on growth, caloric requirements for weight maintenance and weight increase, fertility, lactation
performance, and serum cholesterol levels was compared with that of similar diets containing lard, coconut oil, or no fat.
Among male rats maintained on diets containing 20% lard or 20% MCT and .09% linoleic acid for 18 months no differences were
observed between the groups other than the depressed body weight and lowered serum cholesterol levels of the group fed MCT.
When groups of male rats were kept at constant weight by the daily restricted feeding of diets containing lard, MCT, or coconut
oil or no fat plus 2% linoleic acid, the weight-maintenance requirements of the group fed MCT were higher than of those on
lard and coconut oil and even somewhat higher than the requirements of the animals fed the fat-free diet. The requirements
for weight increase over those for maintenance were 0.9 g. per gram increase for all diets. Additional linoleic acid in the
MCT diet decreased the weight and maintenance differences between groups fed MCT and lard.
The lactation performance of mothers on MCT plus .09% linoleic acid was poor. The second generation animals initially showed
signs of more severe linoleic acid deficiency which however disaappeared without linoleic acid supplements.
Some cholesterol levels of animals on MCT were significantly below those of groups on lard. Addition of linoleic acid to the
MCT diet did not change the results.
Presented at the 48th Annual Meeting, American Oil Chemists’ Society, April 28 to May 1, 1957, New Orleans, La. 相似文献
7.
Formation of certain radiolysis products from palmitic acid, oleic acid, tripalmitin and triolein has provided a means for
comparing the radiolytic effects in saturated and unsaturated triglycerides and fatty acids. These substances were chosen
to represent the major constituents of fat found in beef. Fractionation and concentration of radiolytic compounds from the
irradiated samples was accomplished by the means of size exclusion chromatography. Quantitative and qualitative analyses were
performed using a combined GC/MS computer system. In addition to the primary radiolytic compounds, recombination products
of relatively high molecular weight and various propanediol diesters from the corresponding glyceryl moities were identified.
Quantitative analyses indicated a greater yield of various radiolytic compounds from free fatty acids than from the corresponding
triglycerides. Similarly, radiolytic compounds were produced in greater quantities from the saturated fats than the unsaturated
fats. Most of the radiolytic compounds identified in this study have not been previously reported. 相似文献
8.
Maternal dietary conjugated linoleic acid alters hepatic triacylglycerol and tissue fatty acids in hatched chicks 总被引:1,自引:0,他引:1
The effects of feeding CLA to hens on newly hatched chick hepatic and carcass lipid content, liver TAG accumulation, and FA
incorporation in chick tissues such as liver, heart, brain, and adipose were studied. These tissues were selected owing to
their respective roles in lipid assimilation (liver), as a major oxidation site (heart), as a site enriched with long-chain
polyunsaturates for function (brain), and as a storage depot (adipose). Eggs with no, low, or high levels of CLA were produced
by feeding hens a corn-soybean meal-basal diet containing 3% (w/w) corn oil (Control), 2.5% corn oil +0.5% CLA oil (CLA1),
or 2% corn oil +1.0% CLA oil (CLA2). The egg yolk content of total CLA was 0.0, 1.0, and 2.6% for Control, CLA1, and CLA2,
respectively (P<0.05). Maternal dietary CLA resulted in a decrease in chick carcass total fat (P<0.05). Liver tissue of CLA2 chicks had the lowest fat content (P<0.05). The liver TAG content was 8.2, 5.8, and 5.1 mg/g for Control, CLA1, and CLA2 chicks, respectively (P<0.05). The chicks hatched from CLA1 and CLA2 incorporated higher levels of cis-9,trans-11 CLA in the liver, plasma, adipose, and brain than Control (P<0.05). The content of 18∶0 was higher in the liver, plasma adipose, and brain of CLA1 and CLA2 than Control (P<0.05), but no difference was observed in the 18∶0 content of heart tissue. A significant reduction in 18∶1 was observed in
the liver, plasma, adipose, heart, and brain of CLA1 and CLA2 chicks (P<0.05). DHA (22∶6n−3) was reduced in the heart and brain of CLA1 and CLA2 chicks (P<0.05). No difference was observed in carcass weight, dry matter, or ash content of chicks (P>0.05). The hatchabilities of fertile eggs were 78, 34, and 38% for Control, CLA1, and CLA2, respectively (P<0.05). The early dead chicks were higher in CLA1 and CLA2 than Control (18 and 32% compared with 9% for Control), and alive
but not hatched chicks were 15 and 19% for CLA1 and CLA2, compared with 8% for Control (P<0.05). Maternal supplementation with CLA leads to a reduction in hatchability, liver TAG, and carcass total fat in newly
hatched chicks. 相似文献
9.
James N. Bollinger Raymond Reiser 《Journal of the American Oil Chemists' Society》1965,42(12):1130-1133
The metabolic fates of dietary tricaprylin, trimyristin, tripalmitin, triolein, and trilinolein at the 15% level were followed
with tracer doses of the corresponding C14-labeled acids. Distribution of the label in respiratory C14O2 and in fatty acids of adipose tissue and liver lipids as well as the fatty acid composition of these unfractionated tissue
lipids led to the following conclusions:
Tissue fatty acid compositional homeostasis is limited mainly by the degrees to which dietary fatty acids can be converted
to endogenous fatty acids. Other factors, such as their effects on lipogenesis and the relative degrees to which they are
catabolized and stored, also play roles. 相似文献
10.
Rapidly growing neonatal mammals accrete relatively large quantities of long chain (≥C20) polyunsaturated fatty acids (LCP) in membrane phospholipids. We have examined accumulation of ω6 LCP in suckling neonatal
rat pups during the first 14 d of life when their dams received essential fatty acids in the form of triglycerides containing
linoleic acid or arachidonic acid. Dietary levels of these fatty acids were either 1 or 5% of total dietary fatty acids. The
fatty acid profile of pup stomach contents (composed solely of the dams' milk) and plasma lipids, as well as liver and brain
phospholipids, were determined. Stomach linoleic and arachidonic acid levels reflected the diet of the dams. Pup plasma and
liver arachidonic acid levels increased progressively from the group receiving 1% linoleic acid to 5% linoleic acid and from
1% arachidonic acid to 5% arachidonic acid. Interestingly, brain phosphatidylethanolamine and phosphatidylcholine arachidonic
acid levels were more stable than plasma or liver levels. These results suggest that the brain may be capable of either selective
transport of ω6 LCP or chain elongation/desaturation of linoleic acid. These data indicate that care must be exercised when
adding LCP to infant formula since widely divergent accretion rates of arachidonic acid may occur in various tissues. 相似文献
11.
Data on crystal lattices of 13 different mixtures of the system palmitic acid:stearic acid (C16/C18) could be obtained by means of X-ray and electron diffraction. The modification occurring in all concentrations was found
to be in conformity with the known γ4- or C-form of the pure components. It is characterized by the fact that, in mixtures with 95-60 mol % stearic acid, the shorter
chained palmitic acid molecules may be incorporated in the crystal lattice of pure stearic acid without dimension c of the
unit cell being changed. In concentration ranges of 50–20% C18-molecules, one form of mixture which proves to be stable is characterized by constancy of nearly all unit cell parameters
of various mixture ratios. From SP10 to SP0, the lattice constants of pure palmitic acid are mainly obtained. The occurrence
of C18-molecules of up to 10% in the unit cell of palmitic acid results in a slight decrease of the angle β by 1–2o and an enlargement of the distance to neighbored molecules. 相似文献
12.
13.
Fat-deficient rats were fed different amounts of methyl linoleate for increasing periods of time. The fatty acid composition
of triglycerides and phospholipids of epididymal fat pad, epirenal fat depot, intestinal fat depot, liver, and the pool of
heart, kidney, lungs and pancreas was determined. The distribution of the total amount of linoleic and arachidonic acid incorporated
into phospholipids and triglycerides per rat was calculated. Phospholipids and triglycerides of depot tissues presented different
fatty acid compositions.
Although the phospholipids of liver and the pool of heart, kidney, lung and pancreas specifically incorporated linoleic acid
at the beginning they very rapidly attained a rather steady composition, whereas triglycerides went on incorporating the acid.
The amount of linoleic acid incorporated into the phospholipids of depot tissues was rather small. The triglycerides undoubtedly
contributed in the highest proportion to the total pool of linoleic acid. However, the highest proportion of arachidonic acid
was found in the total pool of phospholipids.
The total amount of linoleic acid incorporated into the phospholipids was an approximately lineal function of the amount of
phospholipids independent of period of administration and doses of methyl linoleate. Besides presenting two lineal functions
of the amount of phospholipids, arachidonic acid showed a vertical increase coincident with a vertical decrease of the amount
of eicosa-5,8,11-trienoic acid. At this period no change in the amount of the phospholipid was shown. This phenomenon is explaioned
as a possible direct replacement of eicosatrienoic acid by arachidonic acid. 相似文献
14.
Starting three weeks before mating, 12 groups of female rats were fed different amounts of linoleic acid (18∶2n−6). Their
male pups were killed when 21-days-old. Varying the dietary 18∶2n−6 content between 150 and 6200 mg/100 g food intake had
the following results. Linoleic acid levels remained very low in brain, myelin, synaptosomes, and retina. In contrast, 18∶2n−6
levels increased in sciatic nerve. In heart, linoleic acid levels were high, but were not related to dietary linoleic acid
intake. Levels of 18∶2n−6 were significantly increased in liver, lung, kidney, and testicle and were even higher in muscle
and adipose tissue. On the other hand, in heart a constant amount of 18∶2n−6 was found at a low level of dietary 18∶2n−6.
Constant levels of arachidonic acid (20∶4n−6) were reached at 150 mg/100 g diet in all nerve structures, and at 300 mg/100g
diet in testicle and muscle, at 800 mg/100 g diet in kidney, and at 1200 mg/100 g diet in liver, lung, and heart. Constant
adrenic acid (22∶4n−6) levels were obtained at 150, 900, and 1200 mg/100 g diet in myelin, sciatic nerve, and brain, respectively.
Minimal levels were difficult to determine. In all fractions examined accumulation of docosapentaenoic acid (22∶5n−6) was
the most direct and specific consequence of increasing amounts of dietary 18∶2n−6. Tissue eicosapentaenoic acid (20∶5n−3)
and 22∶5n−3 levels were relatively independent of dietary 18∶2n−6 intake, except in lung, liver, and kidney. In several organs
(muscle, lung, kidney, liver, heart) as well as in myelin, very low levels of dietary linoleic acid led to an increase in
20∶5n−3. Dietary requirements for 18∶2n−6 varied from 150 to 1200 mg/100 g food intake, depending on the organ and the nature
of the tissue fatty acid. Therefore, the minimum dietary requirement is estimated to be about 1200 mg/100 g (i.e., the level
that ensures stable and constant amounts of arachidonic acid). 相似文献
15.
A study was made of the influence of semisynthetic diets of low and high unsaturation on the fatty acid composition and desaturation-chain
elongation enzymatic activity of the liver microsomal fractions of male Sprague-Dawley rats of different ages. Groups of rats
were fed 5 or 20% coconut oil (CO), or a 5 or 20% mixture of corn and menhaden oils (3∶7) (CME) from weaning to 100 wk of
age. Growth rate and food consumption were measured during this period in which animals were sacrificed at 36, 57, 77 and
100 wk of age. Both the level and composition of the dietary fat supplements produced marked effects on the fatty acid composition
of the liver microsomal lipids. In general, the fatty acid composition of the microsomal fractions reflected that of the dietary
fat and was more unsaturated with the higher level of fat fed. The rate of conversion of linoleic to arachidonic acid in assays
performed in vitro with liver microsomal preparations from animals of the different groups also showed marked differences.
The 6-desaturase-chain elongation activity was higher in the 5% than 20% group and corresponded to the essential fatty acid
(EFA) status of the animals in these groups as represented by the triene-tetraene ratio of the microsomal lipid. The relationship
of the 6-desaturase activity to fatty acid composition of the microsomal lipid indicated that if varied directly with the
level of 20∶3ω9, 18∶1 and 16∶1 and was inhibited by arachidonic acid. The activity of the 6-desaturase enzyme system was lowest
in the liver microsomal fraction obtained from the animals fed the CME diets and appeared to be suppressed by the high levels
of 20∶5 and 22∶6 that accumulated in the microsomal lipid. Accordingly, the levels of arachidonic acid were lower in the microsomal
lipid of these groups than those of the corresponding CO groups in spite of a greater abundance of linoleic acid in the diet.
The data suggest that the activity of the 6-desaturase-chain elongation system is regulated by the fatty acid composition
of the microsomal lipid as influenced by the composition of the dietary fat. 相似文献
16.
Influence of dietary saturated fatty acids on the regulation of plasma cholesterol concentration 总被引:1,自引:1,他引:0
The specific effects of individual fatty acids (FA) on plasma cholesterol levels, in the range habitually consumed by humans,
is not usually presented by the literature. Conclusions have been made regarding the cholesterolemic effect of individual
FA, even though these FA cannot be tested individually. It appears that FA balance of the diet may be more important than
individual FA intakes. Variation in plasma cholesterol response to diet is influenced by many factors, such as gene-nutrient
interactions. The effect on human health of current processes used in the food industry that are certain to change dietary
fat composition and TG structure is yet to be fully explored. Some of the relevant research regarding dietary fat and plasma
cholesterol levels is reviewed. 相似文献
17.
Male Sprague-Dawley rats, 3 weeks of age, were fed semisynthetic diets containing test oils at 20% by weight for 3 days, 1
week, and 16 weeks. The test oils contained up to 22.3% erucic acid. Growth retardation was evident in rats fed rapeseed oil
high in erucic acid, and soybean oil and Tower rapeseed oil diets containing about 5% erucic acid. Cardiac triglyceride accumulation
was found in rats fed diets containing about 5% erucic acid but not in rats fed Tower rapeseed oil which contains 0.2% of
this acid. The cardiac free fatty acid levels were low, 50–100 μg/g of wet heart tissue, and were not affected by feeding
diets containing about 5% erucic acid. Feeding a diet containing a high erucic acid rapeseed oil did result in higher free
fatty acid levels but only at 3 days and 1 week; the level at 16 weeks was similar to the other oils. The fatty acid analysis
of cardiac triglycerides and free fatty acids showed high percentages of erucic acid at 3 days and 1 week; at 16 weeks these
levels had declined significantly. The results indicate that the accumulated erucic and eicosenoic acids, at 3 days and 1
week, accounted for the increase in cardiac free fatty acids when rats were fed the high erucic acid rapeseed oil. There appears
to be no evidence that the early cardiac triglyceride or free fatty acid accumulation is related to the formation of the long
term myocardial lesions.
Contribution No. 739 Animal Research Institute. 相似文献
18.
Lucy D. A. Chumpitaz Lilian F. Coutinho Antonio J. A. Meirelles 《Journal of the American Oil Chemists' Society》1999,76(3):379-382
Surface tension as a function of temperature was measured for four fatty acids (lauric, myristic, palmitic, and oleic) and two triglycerides (tricaprylin and tripalmitin). These surface tension measurements were performed using a K12 vers. 3.1 (Krüss GmbH) tensiometer at temperatures from 20 (or the melting point of each substance) to 90°C. The constants for a van der Waals-type correlation as well as for a linear equation are presented. Both equations are quite accurate, presenting mean deviations not exceeding 0.570%. Such correlation constants are valuable in the design or evaluation of processing equipment, especially that involving gas-liquid contact such as distillation and stripping columns, deodorizers, reactors, and equipment for physical refining. 相似文献
19.
Nine diets, each containing different levels of linoleic acid (18∶2ω6) and linolenic (18∶3ω3) were fed to duplicate groups of rainbow trout for 14 weeks. The growth rate, feed efficiency, accumulated mortality, and fatty acid composition of neutral fat and phospholipids of these groups of fish were determined. The growth was slow in the groups of fish receiving diets containing (A) low concentration of 18∶3ω3 and (B) high concentration (5%) of 18∶2ω6. The accumulated mortality was high in these groups of fish. The diet containing 1% 18∶3ω3 alone supported rapid fish growth with low mortality. The feed efficiency of this diet was also high. The metabolism of 18∶2ω6 and 18∶3ω3 in fish and their conversion to more unsaturated fatty acids typical of fish lipids was investigated. 相似文献
20.
Stability of cyclopropane and conjugated linoleic acids during fatty acid quantification in lactic acid bacteria 总被引:4,自引:0,他引:4
Seven methods commonly used for fatty acid analysis of microgrganisms and foods were compared to establish the best for the
analysis of lyophilized lactic acid bacteria. One of these methods involves fat extraction followed by methylation of fatty
acids, while the other methods use a direct methylation of the samples, under different operating conditions (e.g., reaction
temperature and time, reagents, and pH). Fatty acid methyl esters were identified by gas chromatography-mass spectrometry
and quantified by on-column capillary gas chromatography. Two reliable methods for the analysis of fatty acids in bacteria
were selected and further improved. They guarantee high recovery of classes of fragile fatty acids, such as cyclopropane and
conjugated acids, and a high degree of methylation for all types of fatty acid esters. These two direct methylation methods
have already been successfully applied to the analysis of fatty acids in foods. They represent a rapid and highly reliable
alternative to classical time-and solvent-consuming methods and they give the fatty acid profile and the amount of each fatty
acid. Using these methods, conjugated linoleic acids were identified and quantified in lactic acid bacteria. 相似文献