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Comparative analysis of EPA and DHA in fish oil nutritional capsules by GC-MS

Authors:
  • Guangxi Botanical Garden of Medicinal Plant

Abstract and Figures

Fish oil is a popular nutritional product consumed in Hong Kong. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are the two main bioactive components responsible for the health benefits of fish oil. Market survey in Hong Kong demonstrated that various fish oil capsules with different origins and prices are sold simultaneously. However, these capsules are labelled with same ingredient levels, namely EPA 180 mg/g and DHA 120 mg/g. This situation makes the consumers very confused. To evaluate the quality of various fish oil capsules, a comparative analysis of the contents of EPA and DHA in fish oil is crucial. A gas chromatography-mass spectrometry (GC-MS) method was developed for identification and determination of EPA and DHA in fish oil capsules. A comprehensive validation of the developed method was conducted. Ten batches of fish oil capsules samples purchased from drugstores of Hong Kong were analyzed by using the developed method. The present method presented good sensitivity, precision and accuracy. The limits of detection (LOD) for EPA and DHA were 0.08 ng and 0.21 ng, respectively. The relative standard deviation (RSD) values of EPA and DHA for precision tests were both less than 1.05%; and the recovery for accuracy test of EPA and DHA were 100.50% and 103.83%, respectively. In ten fish oil samples, the contents of EPA ranged from 39.52 mg/g to 509.16 mg/g, and the contents of DHA ranged from 35.14 mg/g to 645.70 mg/g. The present method is suitable for the quantitative analysis of EPA and DHA in fish oil capsules. There is a significant variation in the contents of the quantified components in fish oil samples, and there is not a linear relationship between price and contents of EPA and DHA. Strict supervision of the labelling of the fish oil capsules is urgently needed.
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R E S E A R C H Open Access
Comparative analysis of EPA and DHA in fish oil
nutritional capsules by GC-MS
Tao Yi
1*
, Shuk-Man Li
1
, Jia-Yi Fan
1
, Lan-Lan Fan
2
, Zhi-Feng Zhang
3
, Pei Luo
3
, Xiao-Jun Zhang
4
, Jian-Gang Wang
4
,
Lin Zhu
1
, Zhong-Zhen Zhao
1
and Hu-Biao Chen
1*
Abstract
Background: Fish oil is a popular nutritional product consumed in Hong Kong. Eicosapentaenoic acid (EPA) and
docosahexaenoic acid (DHA) are the two main bioactive components responsible for the health benefits of fish oil.
Market survey in Hong Kong demonstrated that various fish oil capsules with different origins and prices are sold
simultaneously. However, these capsules are labelled with same ingredient levels, namely EPA 180 mg/g and DHA
120 mg/g. This situation makes the consumers very confused. To evaluate the quality of various fish oil capsules, a
comparative analysis of the contents of EPA and DHA in fish oil is crucial.
Methods: Agaschromatographymass spectrometry (GC-MS) method was developed for identification and
determination of EPA and DHA in fish oil capsules. A comprehensive validation of the developed method was
conducted. Ten batches of fish oil capsules samples purchased from drugstores of Hong Kong were analyzed by
usingthedevelopedmethod.
Results: The present method presented good sensitivity, precision and accuracy. The limits of detection (LOD) for
EPA and DHA were 0.08 ng and 0.21 ng, respectively. The relative standard deviation (RSD) values of EPA and DHA for
repeatability tests were both less than 1.05%; and the recovery for accuracy test of EPA and DHA were 100.50% and
103.83%, respectively. In ten fish oil samples, the contents of EPA ranged from 39.52 mg/g to 509.16 mg/g, and the
contents of DHA ranged from 35.14 mg/g to 645.70 mg/g.
Conclusion: The present method is suitable for the quantitative analysis of EPA and DHA in fish oil capsules. There is a
significant variation in the contents of the quantified components in fish oil samples, and there is not a linear relationship
between price and contents of EPA and DHA. Strict supervision of the labelling of the fish oil capsules is urgently needed.
Keywords: Fish oil, EPA, DHA, GC-MS, Comparative analysis
Background
Omega-3 polyunsaturated fatty acids, which include the
fish oil components eicosapentaenoic acid (EPA) and
docosahexaenoic acid (DHA, Figure 1), are essential for
humans as cannot be synthesized by the human body
[1]. It has been reported that omega-3 fatty acids are
very important in preventing and managing heart disease
[2]. Findings show omega-3 fish oil may help to lower
blood pressure [3], reduce triglycerides accumulation [4],
slow the development of plaque in the arteries [5], reduce
the chance of abnormal heart rhythm [6], reduce the
likelihood of heart attack and stroke, and lessen the
chance of sudden cardiac death in people with heart dis-
ease [7]. Omega-3 parenteral nutrition can reduce the rate
of inflammatory complications after surgery [1]. It is also
thought that EPA in particular may possess some bene-
ficial therapeutic potential in mental conditions, such
as schizophrenia, depression, hyperactivity and atten-
tion symptoms [8]. DHA is essential for the growth and
functional development of the brain in infants [9], and
is also required for maintenance of normal brain func-
tion in adults [10,11]. The FDA states it is safe to take
up to 3 g of omega-3 per day to lower the risk for coron-
ary heart disease (CHD) and maintain health [12]. Besides,
the American Heart Association (AHA) recommends
everyone eat fish (particularly fatty fish) at least twice a
* Correspondence: yitao@hkbu.edu.hk;hbchen@hkbu.edu.hk
1
School of Chinese Medicine, Hong Kong Baptist University, Hong Kong
Special Administrative Region, Hong Kong, China
Full list of author information is available at the end of the article
© 2014 Yi et al.; licensee BioMed Central. This is an Open Access article distributed under the terms of the Creative Commons
Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution , and
reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain
Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article,
unless otherwise stated.
Yi et al. Lipids in Health and Disease 2014, 13:190
http://www.lipidworld.com/content/13/1/190
week. As omega-3 fatty acids are deemed important from
authoritative bodies, supplementation in addition to food
sources may need to be considered to help U.S. adults
meet recommendations [13].
In the past 10 years, many people have taken omega-3
fish oil supplements for their health benefits. Hong Kong
is one of the strongest markets for health supplements
in Asia [14], and more and more fish oil products are
being sold in the markets. These fish oils come from
different sources, and product prices vary significantly.
However, these products are labelled with same ingredi-
ent levels, namely EPA 180 mg/g and DHA 120 mg/g
(Table 1). Confronted with this variety, consumers are
eager to know whether these fish oils contain same EPA
and DHA contents? Whether there is relationship between
the EPA/DHA contents and the price or source? Are the
more expensive fish oil products really of better quality?
To answer these questions, a comparative analysis of the
contents of EPA and DHA in commercially available fish
oil is urgently needed.
The determination of EPA and DHA in fish oil has been
reported by high-performance liquid chromatography
(HPLC) [15,16] and liquid chromatography-mass spec-
trometry (LC-MS) [17,18]. However, the HPLC is not
sensitive enough and the cost of LC-MS is high. In the
present study, a new gas chromatographymass spectrom-
etry (GC-MS) method was developed for the analysis of
fish oil. The samples bought from different drugstores in
Hong Kong were analyzed to determine DHA and EPA
contents. The results demonstrated that our method is
highly precise and accurate, and is therefore suitable for
the determination of EPA and DHA in fish oil. Significant
variation in the contents of EPA and DHA in fish oil
samples was founded, and there is not a linear relationship
between price and contents of EPA and DHA. Higher
price can not guarantee higher contents of EPA and
DHA. But because fish oil is expensive and its health
claims are so significant, this is one product the govern-
ment should seriously monitor.
Experimental
Materials
The sources of the fish oil capsule samples are listed in
Table 1. Corresponding voucher specimens were deposited
in the School of Chinese Medicine, Hong Kong Baptist
University.
Reagents and chemicals
The standard compounds of eicosapentaenoic acid methyl
ester, docosahexaenoic acid methyl ester and Supelco® 37
component fame mix were purchased from Sigma-Aldrich
(St. Louis, MO, USA). The purity of these chemical stan-
dards was more than 98% by GC-MS.
N-hexane was used as a solvent in GC-MS analysis,
which was purchased from the RCI Lab-Scan Limited
(Bangkok, Thailand). Potassium hydroxide and sodium
Figure 1 The chemical structures of EPA and DHA.
Table 1 The original sources, prices and contents of EPA and DHA in ten batches of fish oil capsule samples bought in
Hong Kong (n=3)
Sample
no.
Labelled
origin
Price
(HK$/g)
Labelled contents (mg/g) Determined contents (mg/g)
EPA DHA EPA DHA
1
a
USA 1.98
180 120
200.45 201.45
2 Australia 1.68 148.05 137.15
3 USA 1.53 509.16 501.18
4 USA 1.49 418.54 645.70
5 Australia 1.02 132.44 123.26
6 USA 0.98 361.36 419.73
7 New Zealand 0.65 208.42 204.72
8 USA 0.64 166.42 125.33
9 USA 0.34 39.52 35.14
10 USA 0.23 112.19 153.11
a
Samples are listed in order of decreasing price; that is, the most expensive are listed first.
Yi et al. Lipids in Health and Disease 2014, 13:190 Page 2 of 6
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chloride of analytical grade was purchased from Uni-Chem
(Shanghai, China). Boron trifluoride methanol complex so-
lution (13-15% BF
3
basis), used to carry out methyl esterifi-
cation, was purchased from Sigma-Aldrich (St. Louis, MO,
USA). Water was purified using a Milli-Q water system
(Millipore; Bedford, MA, USA).
GCMS instrumentation and conditions
Shimadzu QP2010 GC-MS system (Kyoto, Japan) was used
for qualitative and quantitative analysis of fish oil. DB-5 ms
high resolution capillary column (Dikma Technologies.
thickness: 0.25 μm, length: 30 m, diameter: 0.25 mm)
was used for sample separation.
For temperature programming, the oven was maintained
at 80°C for one minute and then increased at a rate of 10°C
per minute to 250°C, the rate was then slowed to 8°C per
minute until 280°C was reached and maintained for 5 min.
Split injection was conducted with a split ratio of 10:1, and
helium was used as the carrier gas at a rate of 0.8 ml/min,
with the volume of injection as 1 μL. The mass spec-
trometer was operated in electron-impact (EI) mode. Pre-
column pressure: 70 kPa. Injection temperature: 250°C.
Ion source: EI (200°C). Interface temperature: 280°C. Elec-
tron energy: 70 eV. Solvent delay: 5.5 min. For qualitative
analysis, the full scan mode was used and the scan range
was 40400 m/z. For quantitative analysis, selective ion
mode was used, and m/z 79 was chosen as the ion frag-
ment of EPA and DHA.
Preparation of standard and sample solutions
The stock solutions of EPA methyl ester (5 mg/L) and
DHA methyl ester (2.5 mg/L) were prepared in n-hexane
and stored in the refrigerator. The working solutions were
prepared by appropriate dilution of the stock solutions
with n-hexane, and the resulting concentrations of were 1,
2.5, 5, 10, 20, 25 and 30 mg/L. DHA was prepared in serial
dilutions of 2, 5, 10, 20, 40, 50 and 60 mg/L. Calibration
standard solution (1 μL) was injected for GC-MS analysis.
The preparation of sample solutions was performed as
previously described with modifications [19]. Samples were
obtained from fish oil capsules by puncturing the capsule
with a needle syringe. Each sample of approximately 60 mg
was weighed accurately and placed in a centrifuge tube
with a ground stopper. 3 mL potassium hydroxide metha-
nol solution (0.5 M) was added. The contents were thor-
oughly mixed, and then the tube was filled with nitrogen
gas, heated in a water bath at 60°C, shaken three times in
the course of 20 min. When the oil droplets had disap-
peared completely and the solution was transparent, 3 mL
boron trifluoride methanol complex solution was added,
A
12
36
7
8
4
5
B
C
7
8
Figure 2 Typical GC-MS chromatograms of (A) the mix standard and (B) fish oil sample at full scan mode; and (C) fish oil sample at
selective ion mode. 1, Methyl myristate (18.4 min); 2, Methyl palmitoleinate (25.5 min); 3, Methyl palmitate (26.5 min); 4, Methyl heptadecanoate
(33.1 min); 5, Linoleic acid methyl ester (33.7 min); 6, Octadecenoic acid methyl ester (34.0 min); 7, Eicosapentaenoic acid methyl ester (40.8 min);
8, Docosahexaenoic acid methyl ester (48.5 min).
Yi et al. Lipids in Health and Disease 2014, 13:190 Page 3 of 6
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and the mixture cooled. Each tube was then filled with ni-
trogen gas, and placed in a water bath at 60°C for 5 min.
Saturated sodium chloride solution of 2 mL and n-hexane
of 2 mL were added and mixed well. After centrifugation
(4000 rpm) for 10 min, the supernatant was drawn off, to
be used as sample solution. Dilution of the supernatant is
necessary in case its concentration falls out of the linear
range. An aliquot of 1 μL supernatant was injected for
GC-MS analysis.
Assay validation and sample determination
Linearity for standards was determined with five data
points over the concentration range of the working solu-
tions. Precision was evaluated by six injections of the sam-
ple solution (batch 1) within one day. Repeatability was
evaluated in intra- and inter-day assays of the fish oil sam-
ple FO1. The stability test was performed by analyzing the
sample solution (batch 1) over a period of 24 h. The rela-
tive standard deviation (RSD) was taken as the measures
of precision, repeatability and stability. Recovery of all the
quantified constituents was determined by sample in dif-
ferent concentration levels using a mixture of standards
with 50, 100 and 200% of the quantified levels of constitu-
ents in the samples. All fish oil samples were analyzed
using this method, and the acid/ester conversion factor
was set to 0.96.
Results and discussion
Optimization of hydrolysis and esterification conditions
EPA and DHA are present in fish oil in the form of vari-
ous triglycerides. To generate a volatile DHA methyl ester
for GC-MS analysis, EPA and DHA are released from the
triglycerides by hydrolysis, and then methyl esterified.
Various hydrolysis and methyl esterification conditions
(different time, temperature, usage of nitrogen gas) were
evaluated to obtain maximum extraction efficiency. The
results demonstrated that incubation of fish oil (c.a.
60 mg) in potassium hydroxide methanol solution (0.5 M,
3 mL) at 60°C for 20 min achieved complete hydrolysis.
Esterification with 3 mL boron trifluoride methanol solu-
tion at 60°C for 5 min provides the most methyl esters.
Moreover, nitrogen used as protection gas ensures less
oxidation and higher stability of the constituent contents.
After further optimization, the best experimental condi-
tions are shown in Preparation of standard and sample
solutions.
Chromatographic conditions and GC-MS identification
The chromatographic conditions such as temperature
gradient and carrier gas flow rate were optimized to achieve
satisfactory separation and sharp peak shape in the chro-
matograms. Full scan mode was used in qualitative tests
because it provides more peaks for identification. For
the qualitative analysis, apart from EPA (7) and DHA
(8), 6 characteristic peaks of constituent chemicals had
been successfully identified with the aid of the reference
standard. They are methyl myristate (1), methyl palmito-
leinate (2), methyl palmitate (3), methyl heptadecanoate
(4), linoleic acid methyl ester (5), and octadecenoic acid
methyl ester (6). The typical GC-MS chromatograms are
shown in Figure 2A and 2B.
In quantitative test, selective ion mode (SIM) was used
due to its higher sensitivity. Considering the abundance
of fragment ions of EPA and DHA in mass spectra
(Additional file 1: Figure S1), m/z 79 was used for calculat-
ing amount of EPA and DHA. The typical chromatogram
is shown in Figure 2C.
Validation of the analysis method
Results for assessment of the validity of the method are
summarized in Table 2, 3 and 4. The data indicate good
linearity between concentrations and peak areas of the ana-
lytes within the test ranges. The limits of detection (LOD)
for EPA and DHA were found to be 0.08 ng and 0.21 ng,
respectively. Therefore, the system was considered to be
sensitive. The relative standard deviation (RSD) values of
intra-day and inter-day variations were not more than
0.59% and 1.00% for EPA, and not more than 1.08% and
1.05% for DHA, respectively. The established method also
had acceptable accuracy with average recovery of
100.50% and 103.83% for EPA and DHA. All these re-
sults demonstrate that the developed GC-MS method
was sufficiently reliable and accurate and is therefore
suitable for quantification of EPA and DHA in fish oil.
Sample analysis
The present method was successfully applied to the quan-
tification of EPA and DHA in fish oil capsule samples, and
the results are summarized in Table 1 and Figure 3. The
results reveal significant variation in the contents of the
quantified components in fish oil samples. Such variations
Table 3 Precision, repeatability and stability of EPA and
DHA
Analyte Precision
(RSD, %, n=3)
Repeatability
(RSD, %, n=3)
Stability
(RSD, %, n=6)
Day
1
Day
2
Day
3
Inter-day
EPA 0.38 0.38 0.59 0.16 1.00 0.85
DHA 0.32 0.08 0.32 1.08 1.05 0.63
Table 2 Linearity calibration curve factors, LOD and LOQ
of EPA and DHA
Analyte Equation Range
(mg/L)
R
2
LOD (ng) LOQ (ng)
EPA y = 41328.56x - 7.85 1-30 0.9999 0.08 0.15
DHA y = 11863.62x + 4.62 2-60 0.9999 0.21 0.60
Yi et al. Lipids in Health and Disease 2014, 13:190 Page 4 of 6
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may be mainly due to the source and processing of the fish
oil.
Fish oils are commercially produced from cold water
fatty fish, including salmon, tuna, sardines, shellfish, and
herring. The contents of EPA and DHA in theses fishes
are significantly varied [20,21]. During the filling of soft
capsules, poor quality fish oil or even vegetable oil may
be added thereby adulterating good quality fish oil [22].
Adulteration can induce unstable contents of EPA and
DHA in the final products, which make the actual con-
tents do not match the label.
Figure 3 also shows that the relationship between the
price and the contents of DHA and EPA are insignificant.
In other words, according to the prices for the various fish
oil sold in markets, it was clear that the contents of EPA
and DHA did not always correlate with price. For ex-
ample, sample 3, 4 and 6 contained higher contents of
EPA and DHA but it was cheaper than samples 1, 2 and 5.
Distinctly, the classification of various prices of fish oil ac-
tually did not distinguish relative quality. This finding con-
firms the need for developing a reliable evaluation method
to ensure the quality of fish oil products.
Conclusions
A GC-MS method was developed for determination of
EPA and DHA content in fish oil capsules. A comprehen-
sive evaluation of the developed method was conducted,
and the method was shown to be highly sensitive, repro-
ducible and accurate. Samples of 10 commercial fish oil
capsule samples bought in Hong Kong retail stores were
tested. The results demonstrated significant variation in
the contents of EPA and DHA in the samples, and there is
not a linear relationship between price and contents of
EPA and DHA. Strict supervision of the labelling of the
fish oil capsules is urgently needed.
Additional file
Additional file 1: Figure S1. The mass spectra of (a) EPA and (b) DHA
methyl ester.
Abbreviations
EPA: Eicosapentaenoic acid; DHA: Docosahexaenoic acid; GC-MS: Gas
chromatographymass spectrometry; LOD: Limit of detection; LOQ: Limit of
quantitation.
Competing interests
The authors declare that they have no competing interests.
Authorscontributions
TY and HBC initiated the study; all authors contributed to designing the
study. The sample extraction was conduct by SML, JYF and LZ. The
optimization of experimental conditions was performed by LLF, ZFZ and PL.
The data analysis was conduct by XJZ, JGW and ZZZ. TY and SML drafted
the manuscript. All authors contributed to data analysis and manuscript
finalization. All authors read and approved the final manuscript.
Acknowledgements
This work was financially supported by the National Science Fund
(no.31060055) of the Peoples Republic of China.
Author details
1
School of Chinese Medicine, Hong Kong Baptist University, Hong Kong
Special Administrative Region, Hong Kong, China.
2
Guangxi Botanical Garden
of Medicinal Plant, Nanning, Guangxi 530023, China.
3
The State Key
Laboratory of Quality Research in Chinese Medicine, Macau University of
Science and Technology, Macau, China.
4
School of Chinese Medicine,
Guangzhou University of Traditional Chinese Medicine, Guangzhou, China.
Received: 7 July 2014 Accepted: 9 December 2014
Published: 13 December 2014
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a
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doi:10.1186/1476-511X-13-190
Cite this article as: Yi et al.:Comparative analysis of EPA and DHA in
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2014 13:190.
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... The GC-MS method, used in fish oil analysis for the determination of EPA and DHA, has been confirmed to be effective and accurate. 39 Also, EPA and DHA are to be analyzed, by using High Performance Liquid Chromatography (HPLC), and Liquid Chromatography Mass Spectrometry (LC-MS), with the HPLC not as sensitive enough like the GC-MS, while requiring very high costs when using LCMS. 39 Also, clinical trials are to be conducted, in comparing the two products, to observe the effects of EPA and DHA, in the reduction of blood cholesterol levels (LDL, total cholesterol, and triglycerides). ...
... 39 Also, EPA and DHA are to be analyzed, by using High Performance Liquid Chromatography (HPLC), and Liquid Chromatography Mass Spectrometry (LC-MS), with the HPLC not as sensitive enough like the GC-MS, while requiring very high costs when using LCMS. 39 Also, clinical trials are to be conducted, in comparing the two products, to observe the effects of EPA and DHA, in the reduction of blood cholesterol levels (LDL, total cholesterol, and triglycerides). ...
... The GC-MS method, used in fish oil analysis for the determination of EPA and DHA, has been confirmed to be effective and accurate. 39 Also, EPA and DHA are to be analyzed, by using High Performance Liquid Chromatography (HPLC), and Liquid Chromatography Mass Spectrometry (LC-MS), with the HPLC not as sensitive enough like the GC-MS, while requiring very high costs when using LCMS. 39 Also, clinical trials are to be conducted, in comparing the two products, to observe the effects of EPA and DHA, in the reduction of blood cholesterol levels (LDL, total cholesterol, and triglycerides). ...
... 39 Also, EPA and DHA are to be analyzed, by using High Performance Liquid Chromatography (HPLC), and Liquid Chromatography Mass Spectrometry (LC-MS), with the HPLC not as sensitive enough like the GC-MS, while requiring very high costs when using LCMS. 39 Also, clinical trials are to be conducted, in comparing the two products, to observe the effects of EPA and DHA, in the reduction of blood cholesterol levels (LDL, total cholesterol, and triglycerides). ...
... UAE employs two types of instruments: (i) ultrasonic bath, which is the most usual device and entails a stainlesssteel tank with ultrasonic transducers adhered to the base, and an electronic generator, which provides electrical power to the transducer (Chemat et al., 2017;Lavilla & Bendicho, 2017), and (ii) ultrasonic probes, which includes a generator, a transducer bonded to probe and immersed into the vessel containing the feedstock, and a standard and booster horn to enhance the sonication amplitude (Lavilla & Bendicho, 2017). Chemical structures of EPA and DHA (Yi et al., 2014). There are some parameters that affect the effectiveness and efficiency of UAE such as frequency and intensity, reactor design and shape of the probe (if applicable), solvent, temperature, and matrix particle size (Chemat et al., 2017;Pingret, Fabiano-Tixier, & Farid, 2013). ...
... With the intention of attaining the health advantages, the day-to-day ingestion of n-3 PUFAs, particularly EPA and DHA, may achieve an adequate level. Several clinical projects are employing dosages of a maximum of 4 g per day of EPA, DHA, or a mixture of both, as was stated in recent times (Yi et al., 2014). Therefore, upgrading of ω-3 PUFAs, specifically EPA and DHA, have also been an active field of investigation with the aim of manufacturing concentrated high value-added PUFA products (Pereira et al., 2013). ...
Chapter
Fish is regarded as a healthy animal-derived food owing to its remarkable content in macro and micronutrients, which results in a large consumption by humans. Consequently, fishery-related industries generate huge amounts of byproducts that are frequently used to manufacture low-value products or are even discarded. Nevertheless, these marine derivatives present interesting high-value functional features that can be exploited, due to their importance, in the food or nutraceutical industries. In order to obtain these compounds of interest, such as bioactive lipids, it is important to select suitable extraction methods. It is of current concern the use of alternative green cutting edge technologies such as ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE) or supercritical fluid extraction (SFE), which possess some advantages over conventional extractions methods, improving the quality of the extracts and reducing the loss of functional properties of the bioactive compounds obtained. The potential use, and advantages and drawbacks of UAE, MAE, and SFE for the obtainment of lipids from fish derivatives were pinpointed and discussed, in addition to the beneficial effect to the bioactive lipids in human health.
... Alkaloids, phenolic compounds, organic acids, esters, and amino acids are among the chemicals that GC-MS can detect quickly and accurately. us, in this investigation, GC-MS was used to detect and identify phytochemical constituents in A. capitiformis [21][22][23][24]. e network pharmacology approach connects targeted genes with the effects of bioactive compounds; thus, the present study was designed to elucidate the anti-inflammatory effects of the methanolic extract of A. capitiformis stem using a network pharmacology approach. ...
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Perilla oil (PO) has a high unsaturated fatty acids content that is easily oxidised, causing nutritional and functional losses. This study investigated the fabrication of PO in emulsion and microcapsules using whey protein isolate (WPI), gum acacia (GA), maltodextrin (MD) and OSA‐starch as wall materials, aiming to improve the oxidative stability and functionality of the PO. The results showed that both OSA‐starch stabilised emulsion and microcapsules exhibited slower increases in peroxide and p‐anisidine values and a slower decrease in antioxidant capacity than those produced with WPI/GA, WPI/MD, and WPI/GA via complex coacervation. The microcapsules fabricated with OSA‐starch gave a better polydispersity index, encapsulation efficiency, and oxidative stability than the other samples, suggesting effective protection against primary and secondary oxidation during storage. Moreover, the oxidation stability of the emulsions and microcapsules could be improved via complex coacervation, although this technique could result in larger droplet size. Overall, this study contributed to the knowledge of PO emulsions and microcapsules fabrication using protein and polysaccharides and provided insights for improving PO's oxidative stability and functionality.
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The health benefits of docosahexaenoic (DHA) and eicosapentaenoic (EPA) in omega-3 containing supplements are compelling. However, their source and pharmaceutical regulation in Ghana presents two potential problems; quality and safety. This study investigated the quality and safety of some omega-3 containing supplements on the Ghanaian market. Twenty-two over-the-counter commercial brands of omega-3 fish oil supplements were analyzed for their pharmaceutical quality, heavy (mercury), and trace (sodium, potassium, magnesium, iron, and calcium) metal contents to check if they pose health risks to consumers. On their quality attributes, which was evaluated by the uniformity of weight, disintegration time, and content of DHA and EPA, all products sampled passed the uniformity of weight except sample H and S. All sampled products passed the disintegration tests except for brand C and E and all samples did not meet the DHA content per the manufacturers’ label and standard requirements. On EPA content, only samples B and S passed. Almost 90% of the supplements sampled were not of the required quality. Sodium and potassium were detected in all samples, even though none was stated on their labels. All samples contained calcium, iron, and magnesium, but only 5 (24%) manufacturers stated it on their labels. The mercury content ranged from 0.4 to 125 µg/l in the analyzed fish oil supplements. Based on the risk assessment with particular reference to the hazard quotient, consumers taking the products over a prolonged period are at risk of adverse health effects.
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s Fish oil supplements have gained popularity in recent years due to their many health benefits, leading to a rapid increase in the number of fish oil supplements available to consumers during the COVID-19 pandemic. In this study, the fatty acid composition (FA) of 15 commercial fish oil supplements including syrups (SYR) and capsules (CAP) from the Turkish marketplace was analyzed and some quality indices were evaluated. In addition, EPA and DHA content of FA was compared with their label claims. Fish oil supplements were analyzed using gas chromatography-mass spectrometry (GC-MS) to determine their fatty acid composition and content. In fish oil supplements, the content of EPA ranged from 3.51% to 20.51%, and the contents of DHA ranged from 3.28% to 52.42%. The label claims for EPA presented a reasonable accuracy for products examined, but it was observed that the DHA levels of some supplements showed a considerable difference with the labels. EPA and DHA levels of fish oil capsules on the Turkish retail market were more consistent with their claimed label content compared to fish oil syrups. The n3/n6 and PUFA/SFA ratios in the supplements were greater than those recommended by the FAO/WHO. The atherogenicity index (AI) and thrombogenicity index (TI) were below the maximum recommended limit value (1) in terms of coronary heart disease risk. Moreover, most of the supplements had higher lipid quality indices, including fish lipid quality (FLQ), hypocholesterolemic/Hypercholesterolemic (h/H) ratio, health-promoting index (HPI), polyene index (PI), and unsaturation index (UI).
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The American Heart Association’s Strategic Impact Goal Through 2020 and Beyond recommends ≥ two 3.5-oz fish servings per week (preferably oily fish) partly to increase intake of omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). We examined the intake of total fish, fish high in omega-3 fatty acids, α-linolenic acid, EPA, and DHA in U.S. adults (19 + years) using data from the National Health and Nutrition Examination Survey, 2003–2008. Usual intakes from foods alone and from foods plus dietary supplements were determined using the methods from the National Cancer Institute. Mean usual intake of total fish and fish high in omega-3 fatty acids was 0.61 ± 0.03 and 0.15 ± 0.03 oz/day, 0.43 and 0.07 respectively. Total fish and fish high in omega-3 fatty acids median intake was 0.43 and 0.07 oz/day, respectively. Intake from foods alone for ALA, EPA and DHA was 1.5 ± 0.01 g/d, 23 ± 7 mg/d and 63 ± 2 mg/d, respectively. ALA, EPA and DHA from food only median intakes were 1.4 g/d, 18 mg/d and 50 mg/d, respectively. Intake of ALA, EPA and DHA from foods and dietary supplements was 1.6 ± 0.04 g/d, 41 ± 4 mg/d and 72 ± 4 mg/d, respectively. While intakes of fish high in omega-3 fatty acids were higher in older adults (0.13 ± 0.01 oz/d for those 19–50 yrs and 0.19 ± 0.02 oz/d for those 51+ year; p < 0.01) and in males as compared to females (0.18 ± 0.02 vs 0.13 ± 0.01 oz/d, respectively; p < 0.05), few consumed recommended levels. Males also had higher (p < 0.05) intake of EPA and DHA from foods and dietary supplements relative to females (44 ± 6 vs 39 ± 4 and 90 ± 7 vs 59 ± 4 mg/d, respectively) and older adults had higher intakes of EPA, but not DHA compared to younger adults (EPA: 34 ± 3 vs 58 ± 9, p < 0.05; DHA: 68 ± 4 vs 81 ± 6, p < 0.05). As omega-3 fatty acids are deemed important from authoritative bodies, supplementation in addition to food sources may need to be considered to help U.S. adults meet recommendations.
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Nutrients such as omega-3 fatty acids including fish oil components eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) suppress the growth and promote apoptosis of tumor cells, improve immune function and reduce the effects of systemic inflammatory response syndrome. We sought to investigate the effect of omega-3 fish oil fat emulsion-based parenteral nutrition (PN) on nutritional state, immune function, inflammatory reaction, expression of tumor factors and complication incidence in patients after surgical resection of gastric cancer. Forty-eight patients after surgical operation of gastric tumor in hospital were randomly divided into the control group and intervention group. Patients in both groups were treated with iso-nitrogen and iso-caloric parenteral nutrition support. In addition, the intervention group received omega-3 fish oil fat emulsion and the control group received soybean oil. The indicators of nutrition, immune function and inflammation in the two groups were detected on the day before the operation and postoperative day 6. The rate of complication was compared between the two groups. There was no significant difference in nutritional state, liver function and renal function between the two groups (P > 0.05). However, the levels of inflammatory markers were significantly decreased (P < 0.01), and the rate of complication was also decreased in the intervention group as compared with the control group. omega-3 fish oil fat emulsion-based parenteral nutrition alleviates the inflammatory reaction and reduces the rate of inflammatory complications.
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Background: Docosahexaenoic acid (DHA) is important for brain function, and its status is dependent on dietary intakes. Therefore, individuals who consume diets low in omega-3 (n-3) polyunsaturated fatty acids may cognitively benefit from DHA supplementation. Sex and apolipoprotein E genotype (APOE) affect cognition and may modulate the response to DHA supplementation. Objectives: We investigated whether a DHA supplement improves cognitive performance in healthy young adults and whether sex and APOE modulate the response. Design: Healthy adults (n = 176; age range: 18-45 y; nonsmoking and with a low intake of DHA) completed a 6-mo randomized, placebo-controlled, double-blind intervention in which they consumed 1.16 g DHA/d or a placebo. Cognitive performance was assessed by using a computerized cognitive test battery. For all tests, z scores were calculated and clustered into cognitive domains as follows: episodic and working memory, attention, reaction time (RT) of episodic and working memory, and attention and processing speed. ANCOVA was conducted with sex and APOE as independent variables. Results: RTs of episodic and working memory improved with DHA compared with placebo [mean difference (95% CI): -0.18 SD (-0.33, -0.03 SD) (P = 0.02) and -0.36 SD (-0.58, -0.14 SD) (P = 0.002), respectively]. Sex × treatment interactions occurred for episodic memory (P = 0.006) and the RT of working memory (P = 0.03). Compared with the placebo, DHA improved episodic memory in women [0.28 SD (0.08, 0.48 SD); P = 0.006] and RTs of working memory in men [-0.60 SD (-0.95, -0.25 SD); P = 0.001]. APOE did not affect cognitive function, but there were some indications of APOE × sex × treatment interactions. Conclusions: DHA supplementation improved memory and the RT of memory in healthy, young adults whose habitual diets were low in DHA. The response was modulated by sex. This trial was registered at the New Zealand Clinical Trials Registry (http://www.anzctr.org.au/default.aspx) as ACTRN12610000212055.
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Background Depression is one of the most frequently missed diagnoses in elderly people, with obvious negative effects on quality of life. Various studies have shown that long chain omega-3 polyunsaturated fatty acids (n-3 PUFA) may be useful in its management. Our objective was to evaluate whether a supplement containing n-3 PUFA improves depressive symptoms in depressed elderly patients, and whether the blood fatty acid pattern is correlated with these changes. Methods The severity of depressive symptoms according to the Geriatric Depression Scale (GDS), blood fatty acid composition and erythrocyte phospholipids were analyzed in 46 depressed females aged 66-95y, diagnosed with depression according to DSMIV, within the context of a randomized, double-blind, placebo-controlled trial. 22 depressed females were included in the intervention group (2.5 g/day of n-3 PUFA for 8 weeks), and 24 in the placebo group. We also measured immunological parameters (CD2, CD3, CD4, CD8, CD16, CD19 and cytokines (IL-5, IL-15). Results The mean GDS score and AA/EPA ratio, in whole blood and RBC membrane phospholipids, were significantly lower after 2 months supplementation with n-3 PUFA. A significant correlation between the amelioration of GDS and the AA/EPA ratio with some immunological parameters, such as CD2, CD19, CD4, CD16 and the ratio CD4/CD8, was also found. Nevertheless, omega-3 supplementation did not significantly improve the studied immunological functions. Conclusions n-3 PUFA supplementation ameliorates symptoms in elderly depression. The n-3 PUFA status may be monitored by means of the determination of whole blood AA/EPA ratio.
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Samples of ice algae from the Marginal Ice Zone in the Barents Sea could be divided into two categories: one dominated by assemblages of Melosira arctica, and the other dominated by Nitzschia frigida and associated diatoms. Total lipid from the Melosira assemblages consisted of approximately equal amounts of polar lipids and triacylglycerols. Total lipid from the Nitzschia assemblages contained more triacylglycerols than polar lipids. Total lipid from the Melosira assemblages had higher percentages of C16 PUFA, especially 16:4(n-1) and 20:5(n-3), than that from the Nitzschia assemblages, this reflecting the higher percentages of both C16 PUFA and 20:5(n-3) in polar lipids than in triacylglycerols. Phytoplankton from the pelagic zone were␣richer in flagellates and contained less C16 PUFA and 20:5(n-3) but more C18 PUFA and 22:6(n-3). The dominance of diatoms in the ice-algae assemblages in the Marginal Ice Zone and their high nutritional value as a source of 20:5(n-3) for higher trophic levels are emphasised.
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Introduction: Cardiovascular disease remains the commonest health problem in developed countries, and residual risk after implementing all current therapies is still high. The use of marine omega-3 fatty acids (DHA and EPA) has been recommended to reduce cardiovascular risk by multiple mechanisms. Objectives: To update the current evidence on the influence of omega-3 on the rate of cardiovascular events. Review methods: We used the MEDLINE and EMBASE databases to identify clinical trials and randomized controlled trials of omega-3 fatty acids (with quantified quantities) either in capsules or in dietary intake, compared to placebo or usual diet, equal to or longer than 6 months, and written in English. The primary outcome was a cardiovascular event of any kind and secondary outcomes were all-cause mortality, cardiac death and coronary events. We used RevMan 5·1 (Mantel-Haenszel method). Heterogeneity was assessed by the I2 and Chi2 tests. We included 21 of the 452 pre-selected studies. Results: We found an overall decrease of risk of suffering a cardiovascular event of any kind of 10 % (OR 0·90; [0·85-0·96], p = 0·001), a 9 % decrease of risk of cardiac death (OR 0·91; [0·83-0·99]; p = 0·03), a decrease of coronary events (fatal and non-fatal) of 18 % (OR 0·82; [0·75-0·90]; p < 1 × 10⁻⁴), and a trend to lower total mortality (5 % reduction of risk; OR 0·95; [0·89-1·02]; p = 0·15. Most of the studies analyzed included persons with high cardiovascular risk. Conclusions: marine omega-3 fatty acids are effective in preventing cardiovascular events, cardiac death and coronary events, especially in persons with high cardiovascular risk.
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A chromatographic method has been developed for the determination of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in fish oil dietary supplements containing triglycerides rich in (n–3) polyunsaturated fatty acids (PUFAs). Following the ester saponification, free fatty acids were resolved by TLC into two fractions: i) a more mobile group of saturated and monounsaturated fatty acids and ii) a less mobile group containing PUFAs. The PUFA fraction was further analyzed by HPLC to determine the levels of EPA and DHA in the fish oil sample.