Quantification of EPA and DHAin seafood of the south coast

of BrazilElton Bonafe

Chemistry Department, Universidade Estadual de Maringa, Maringa, Brazil

Ana de AguiarDepartment of Food Engineering, Universidade Estadual de Maringa,

Maringa, Brazil, and

Marcela Boroski, Johny Monteiro, Nilson Souza,Makoto Matsushita and Jesuı Visentainer

Chemistry Department, Universidade Estadual de Maringa, Maringa, Brazil

Abstract

Purpose – The increase in seafood trade in recent years motivates more detailed studies of differentspecies, as well as evaluation of the nutritional quality of their lipid content. Thus, the purpose of thispaper is to evaluate the fatty acid composition, especially the concentrations and fractionation ofomega-3 essential fatty acid in classes of mussels (male and female), oysters, squid, and octopuscaptured on the south coast of Brazil.

Design/methodology/approach – Fatty acid methyl esters were prepared by methylation of totallipids and were separated by gas chromatography. Quantification of LNA, AA, EPA, and DHA wasdone against tricosanoic acid methyl ester as an internal standard. Total lipids were fractionated intoneutral lipids and polar lipids by classical column chromatography.

Findings – The results of this study were as follows: the female mussel had the highest lipid content(3.52 per cent), followed by the male mussel (2.70 per cent), squid (1.05 per cent), octopus (0.79 per cent),and oyster (0.62 per cent). The samples that had the highest percentages of EPA and DHA in their lipidfraction were the female mussel and squid, respectively. The species belonging to the Bivalvia class(mussels and oysters) showed a predominance of PL, while those belonging to the cephalopods class(octopus and squid), showed a predominance of NL. The n-6/n-3 and polyunsaturated fattyacid/saturated fatty acids ratios of all samples analyzed were in accordance with therecommendations. The female mussel had the highest concentration of EPA þ DHA omega-3 fattyacids, corresponding to 1,064.63 mg EPA þ DHA 100 g21 of the sample. So, the consumption ofmussels caught off the southern coast of Brazil provides the omega-3 essential fatty acids.

Originality/value – This paper provides important data concerning lipid quality of seafood caughtoff on the south coast of Brazil.

Keywords Brazil, Seas, Molluscs, Seafood, Mussels, Squid, Oysters, Octopus, Lipid classes, Fatty acids

Paper type Research paper

1. IntroductionDuring the past two decades, the overall scenario of international trade in seafood haschanged in size and structure. In 2007, the Food and Agriculture Organization of theUnited Nations (FAO FISHSTAT Plus, 2007) published a document regarding theannual production of shellfish in the world in continental waters. The production wasestimated at around 38,300 tons (FAO FISHSTAT Plus, 2007). Brazil has favorable

The current issue and full text archive of this journal is available at

www.emeraldinsight.com/0034-6659.htm

EPA and DHAin seafood

401

Nutrition & Food ScienceVol. 41 No. 6, 2011

pp. 401-411q Emerald Group Publishing Limited

0034-6659DOI 10.1108/00346651111181958

conditions for the development of aquaculture, since it has vast amounts of waterresources, in addition to a productive shore. It also has a wealth of species, variousmicroclimates, and areas that are conducive to the activity (Camargo and Pouey, 2005).

Among various seafood species consumed in Brazil, mussels, oysters, squid andoctopus stand out. The lipid portion of these marine species is normally characterizedby high levels of long-chain polyunsaturated fats of n-3 series (Zlatanos et al., 2006;Ozyurt et al., 2006; Talab et al., 2010), prevailing eicosapentaenoic acid (EPA, 20:5 n-3),and docosahexaenoic acid (DHA, 22:6 n-3) fatty acids (Visentainer et al., 2005).Research has shown that DHA is directly involved in the maintenance of biologicalmembranes, retina, cerebral cortex, nerve tissue, testis, and blood platelets (Martin et al.,2006; Ruxton and Derbyshire, 2009). The EPA is related to the vascular system andexhibit antithrombotic and anti-inflammatory actions (Simopoulos, 2004).

The total lipids may contain several lipid-soluble organic substances, which aredivided into two main classes: neutral lipids (NL), known as storage lipids,triacylglycerols being the ones found in the largest quantity (Henderson and Tocher,1987), and polar lipids (PL), which are present as cell membrane constituents(Wang et al., 1990), represented mainly by phospholipids (Graeve and Janssen, 2009).Owing to the complexity of these macronutrients, a detailed evaluation of these classesseparately is required. The objective of this study was to obtain information on lipidclasses, especially EPA and DHA concentrations, both essential omega-3 fatty acids insamples of mussels, oysters, squid and octopus captured on the coast of SantaCatarina, Brazil.

2. Materials and methods2.1 SamplingSamples of mussels – male and female (Perna perna), squid (Loligo plei ), oyster(Crassostrea rhizophorae), and octopus (Octopus vulgaris), were gathered on theEast Coast of Santa Catarina state (Brazil) in January and February 2008. Samples wereimmediately cooled and transported to the laboratory. They were homogenized,minced, and placed in a freezer at 2188C under an N2 atmosphere for further analyses.

2.2 AnalysisThe moisture content was determined according to AOAC (1998). Total lipids weredetermined using the Bligh and Dyer (1959) method. All analysis was performed intriplicate.

2.3 Fatty acid methyl estersFatty acid methyl esters were prepared by methylation of total lipids, as described byJoseph and Ackman (1992). The methyl esters were separated by gas chromatographyin a Varian model 3380 equipped with flame ionization and a cyanopropyl capillarycolumn (100 m £ 0.25 d.i., 0.25mm film thickness, CP-7420 Varian, EUA). The gas flowrates used were 1.2 ml min21 carrier gas (H2), 30 ml min21 make-up gas (N2), and300 ml min21 flame gases (H2 and synthetic air, respectively). The sample splittingrate was 1:100 and the samples (2ml) were injected in triplicate. The operationparameters were as follows: detector temperature of 2258C, injection port temperatureof 2458C, column temperature of 1408C for 5 min, programmed to increase to 2008C at48C min21, to 2208C at 18C min21, and kept at this temperature for 5 min. The peak

NFS41,6

402

areas were determined by the Workstation 5.0 (Varian) acquisition program. For thefatty acid identification, retention times were compared to those of standard methylesters (Sigma, St Louis, MO, USA).

Quantification (mg fatty acid g21 total lipids) was made against tricosanoic acidmethyl ester as an internal standard (IS, 23:0), as described by Joseph and Ackman(1992). Theoretical flame ionization detector correction factor (Visentainer and Franco,2006) values were used to obtain concentration values. Fatty acid contents werecalculated in mg g21 of total lipids by using equation 1:

FA ¼AX WISCFX

AISWX CFAE

ð1Þ

where, FA is mg of fatty acids per g of total lipids, AX is the peak area (fatty acids),AIS is the peak area of IS methyl ester of tricosanoic acid (23:0), WIS is the IS weight(mg) added to the sample (in mg), WX is the sample weight (in mg), CFX is thetheoretical correction factor, and CFAE is the conversion factor necessary to expressresults as mg of fatty acids, rather than as methyl esters. The results were recalculatedin order to be expressed in concentration (100 mg g21 sample).

2.4 Separation of lipid classesTotal lipids were fractionated into NL and PL by classical column chromatography.The process was conducted in a glass chromatography column, 30 cm long by 2 cm ofinternal diameter, containing 25 g of silica gel 60 (70-230 mesh, Merck) as adsorbent,according to the specifications of Johnston et al. (1983). The eluting NL and PL wereperformed using the method described by Maia and Rodriguez-Amaya (1992), with thefollowing eluting sequences: Fraction I – NL (200 ml of a mixture of chloroform with20 per cent acetone), Fraction II – PL (200 ml of methanol). The eluting solvents wereremoved in a rotary evaporator under vacuum at 32-348C with a flow of N2.The fractions were transferred to a 7-ml amber bottle and stored at 2188C. All analysiswas performed in triplicate.

2.5 Statistical analysisThe results were submitted to variance (ANOVA) analysis and Tukey’s test (5 per centprobability) using the software Statistica 5.0 (Statsoft, 1996).

3. Results and discussionTable I shows the moisture and lipid content, as well as fatty acid composition ofsamples of mussels, oysters, squid, and octopus. The results obtained for the totallipids were low, ranging from 0.62 to 3.52 per cent, but consistent with the study bySirot et al. (2008) that found values of total lipids of 1.09, 0.55, 1.33, and 0.36 per cent formussels, oysters, squid, and octopus samples, respectively.

For all species, a predominance of palmitic (16:0), EPA (20:5 n-3), and DHA (22:6 n-3)fatty acids was observed, in agreement with the studies of Navarro and Villanueva(2000).

Studying the mussel (Mytilus edulis), Copeman and Parrish (2004) found higherresults for EPA, and lower for DHA, as compared with those obtained in this study.In the squid sample, alpha-linolenic acid (18:3 n-3, LNA) was not identified, and thelevels of EPA and DHA were 13.24 and 33.72 per cent, respectively. In a similar study

EPA and DHAin seafood

403

MM

FM

SQ

OY

OC

Tot

alli

pid

s2.

70^

0.15

3.52

^0.

211.

05^

0.06

0.62

^0.

04c

0.79

^0.

06cd

Moi

stu

re72

.86^

0.01

74.0

3^

0.12

86.2

6^

0.16

87.4

9^

0.16

c84

.24^

0.14

e

Fatt

yaci

ds

14:0

5.10

^0.

124.

84^

0.06

2.38

^0.

193.

37^

0.06

1.31

^0.

3716

:025

.64^

0.18

24.4

7^

0.33

26.5

4^

0.60

25.5

0^

0.06

20.4

0^

0.44

16:1

n-7

10.0

3^

0.06

9.23

^0.

121.

18^

0.06

2.27

^0.

010.

85^

0.01

17:0

1.40

^0.

071.

41^

0.02

0.29

^0.

012.

22^

0.12

1.74

^0.

0217

:1n

-90.

57^

0.01

0.50

^0.

011.

18^

0.05

TR

TR

18:0

5.35

^0.

055.

65^

0.07

7.62

^0.

106.

46^

0.23

12.6

9^

0.97

18:1

n-9

2.94

^0.

003.

75^

0.05

4.12

^0.

033.

73^

0.17

3.03

^0.

0318

:1n

-73.

04^

0.12

2.76

^0.

031.

56^

0.05

4.48

^0.

131.

91^

0.02

18:2

n-6

2.81

^0.

022.

79^

0.03

0.71

^0.

122.

36^

0.20

TR

18:3

n-3

2.97

^0.

012.

56^

0.03

TR

2.23

^0.

07T

R22

:24.

86^

0.05

4.08

^0.

043.

02^

0.03

8.63

^0.

133.

84^

0.04

20:4

n-6

3.06

^0.

033.

07^

0.03

4.43

^0.

044.

95^

0.21

14.7

9^

0.19

20:5

n-3

14.2

8^

0.10

14.9

9^

0.15

13.2

4^

0.11

13.1

9^

0.09

14.2

1^

0.91

22:6

n-3

17.9

5^

0.12

19.2

3^

0.25

33.7

2^

0.52

20.6

1^

0.13

25.2

1^

0.27

Sum

mati

ons

SF

A37

.49^

0.28

36.3

7^

0.47

36.8

3^

0.53

37.5

5^

0.19

36.1

5^

1.14

PU

FA

45.9

3^

0.31

46.7

3^

0.52

55.1

2^

0.54

51.9

7^

0.36

58.0

5^

1.08

MU

FA

16.5

7^

0.12

16.2

3^

0.17

8.04

^0.

0610

.48^

0.24

5.79

^0.

06n

-65.

88^

0.04

5.87

^0.

065.

14^

0.09

7.31

^0.

1214

.79^

0.19

n-3

35.2

0^

0.23

36.7

8^

0.42

46.9

6^

0.46

36.0

3^

0.16

39.4

2^

1.11

Notes:

Mea

ns

foll

owed

by

dif

fere

nt

lett

ers

inth

esa

me

lin

ear

est

atis

tica

lly

dif

fere

nt

(p,

0.05

)by

Tu

key

’ste

st;M

M,m

ale

mu

ssel

;FM

,fem

ale

mu

ssel

;SQ

,sq

uid

;OY

,oy

ster

;OC

,oct

opu

s,S

FA

,sat

ura

ted

fatt

yac

ids;

MU

FA

,mon

oun

satu

rate

dfa

tty

acid

s;P

UF

A,p

oly

un

satu

rate

dfa

tty

acid

s;n

-6,o

meg

a-6;

n-3

,om

ega-

3;T

R,

trac

e;d

ata

are

pre

sen

ted

asm

ean^

SD

Table I.Fatty acid composition(relative percentage), lipid(per cent w w21), andmoisture (per cent w w21)content of seafoodsamples

NFS41,6

404

with this species (Lolliguncula brevis) conducted by Stowasser et al. (2006), low levels ofLNA (0.6 per cent) and values for EPA and DHA similar to those found in this workwere obtained.

The 18:3 n-3 (LNA) and 18:2 n-6 (LA) were not found in samples of octopus, agreeingwith results obtained by Navarro and Villanueva (2003) in the study of Octopusvulgaris, and with the work of Ozogul et al. (2008), in which the levels of EPA and DHAwere similar to those obtained in this experiment.

As shown in Figure 1, the nutritional ratios n-6/n-3 and saturated fatty acids(SFA)/polyunsaturated fatty acids (PUFA) ranged from 0.11 to 0.37 and 1.23 to 1.69,respectively. The PUFA/SFA ratio in all species analyzed are in agreement with thevalues found by Simopoulos (2002a), who reported that values below 0.4 areinadequate for heath in relation of cardiovascular disease. For all species, this ratiowas above 1.2 (Figure 1). Additionally, the low n-6/n-3 ratio values (Figure 1)indicate that consumption of seafood can help in reestablishing the balance betweenfatty acids n-6 and n-3. Simopoulos (2002b) recommends an n-6/n-3 ratio lowerthan 4.0.

Variations in the percentages of NL and PL were observed in the samples analyzed(Figure 2). The species belonging to the Bivalvia class (mussels and oysters) showeda predominance of PL, while in those belonging to the cephalopods class (octopus andsquid) was observed the predominance of NL.

Table II presents the fatty acid composition in NL and PL of samples. In althoughthere are modern techniques for the separation of lipid classes, such as HPLC (Graeveand Janssen, 2009), this study employs a less sophisticated analysis technique, butthat is based on the same chemical principles. The partition yield ranged from 84 to95 per cent (Figure 2), indicating a good recovery and minimal losses.

Figure 1.Ratios of n-6 and n-3fatty acids (n-6/n-3),

and PUFA/SFA

1.8

1.6

1.4

1.2

1.0

0.8Rat

e

0.6

0.4

0.2

0.0MM MF OY SQ OC

Sample

n-6/n-3PUFA/SFA

EPA and DHAin seafood

405

Palmitic fatty acid was found in greater quantity in both the NL and PL classes(Table II). This acid was not significantly different ( p , 0.05) among samples ofmussels and oysters, but differed statistically from results for squid and octopus.

DHA was the PUFA found in larger amounts in the polar fraction of all samples,and their percentage was significantly different ( p , 0.05) (Table II). ComparingTables I and II, it can be observed that all components present in total lipids wereidentified in fractions of NL and PL, but in different amounts according to each class.

According to the Institute of Medicine (Washington, 2008), the adequate intakelevels of LNA for men and women are 1.6 and 1.1 g day21, respectively. The samplesanalyzed showed concentrations of LNA below the recommended level, and the femalemussel had the highest concentration (79.63 g 100 g21), as compared to the othersamples.

Relevant concentrations of EPA and DHA were found, differently from the LNAlevels found (Table III). Kris-Etherton et al. (2002) recommend the intake of 0.5 gday21of DHA þ EPA for children and 1.0 g day21 for adults. Based on therecommendation of Kris-Etherton et al. (2002) for adults, the intake of about 270 g ofsquid, 130 g of male mussels, or 94 g of female mussels provides the recommendedamount of the summation of long-chain omega-3 essential fatty acids.

4. ConclusionThe analyzed samples of seafood showed fatty acids of important nutritional valuein their lipid fraction, such as EPA and DHA in appreciable quantities, besidesbeing in accordance with the recommendations for the n-6/n-3 and PUFA/SFAratios. Among the analyzed species, the female mussel stood out as having thehighest concentrations of polyunsaturated long-chain omega-3 fatty acids, such asEPA and DHA.

Figure 2.Percentage of classesof PL and NLin seafood samples

60

50

40

30

20

10

0MM MF OY SQ OC

NLPL

Sample

Per

cent

age

NFS41,6

406

Sam

ple

sM

M(P

L)

MM

(NL

)F

M(P

L)

FM

(NL

)S

Q(P

L)

SQ

(NL

)O

Y(P

L)

OY

(NL

)O

C(P

L)

OC

(NL

)

14:0

2.84

^0.

08a

6.75

^0.

10b

1.90

^0.

02c

6.80

^0.

37b

0.47

^0.

01d

3.37

^0.

02e

2.73

^0.

05a

4.43

^0.

12f

0.45

^0.

04d

3.02

^0.

11ea

16:0

19.1

0^

0.07

a28

.47^

0.24

b15

.86^

0.54

cd27

.17^

0.81

b14

.42^

0.23

df

27.6

1^

1.28

b17

.35^

0.51

c32

.28^

0.30

e14

.09^

0.35

f22

.07^

0.34

g

16:1

n-7

4.07

^0.

01a

12.2

0^

0.12

b3.

07^

0.03

c12

.49^

0.23

b0.

31^

0.03

d2.

87^

0.03

c1.

35^

0.03

e4.

36^

0.22

a0.

63^

0.00

d3.

42^

0.06

f

17:0

0.38

^0.

00a

0.54

^0.

01b

0.29

^0.

00a

0.52

^0.

03b

1.49

^0.

01c

1.16

^0.

01d

3.09

^0.

09e

2.53

^0.

02f

0.39

^0.

01a

4.97

^0.

08g

17:1

n-9

2.02

^0.

01a

1.25

^0.

02b

2.08

^0.

02a

1.15

^0.

06c

0.69

^0.

00d

0.36

^0.

00e

TR

TR

TR

TR

18:0

9.31

^0.

59a

4.75

^0.

09b

9.61

^0.

51a

4.65

^0.

11b

12.2

0^

0.47

c10

.95^

0.10

d14

.48^

0.27

e7.

31^

0.29

f13

.35^

0.13

g9.

13^

0.15

a

18:1

n-9

2.39

^0.

03a

4.16

^0.

06b

2.00

^0.

02ac

4.52

^0.

05b

1.79

^0.

05c

12.1

7^

0.40

d2.

98^

0.06

e8.

24^

0.24

f2.

04^

0.06

ac

13.0

4^

0.24

g

18:1

n-7

1.97

^0.

01a

3.18

^0.

05b

1.85

^0.

02ae

2.96

^0.

03b

f1.

04^

0.03

c1.

93^

0.02

ae

4.30

^0.

08d

4.66

^0.

42d

1.56

^0.

03e

2.58

^0.

04f

18:2

n-6

3.83

^0.

14a

2.72

^0.

04b

3.08

^0.

03c

2.55

^0.

03d

0.28

^0.

01e

3.44

^0.

03f

1.13

^0.

02g

0.48

^0.

00h

TR

TR

18:3

n-3

3.25

^0.

01a

2.89

^0.

04b

3.43

^0.

04c

2.42

^0.

02d

TR

TR

1.14

^0.

02e

0.53

^0.

03f

TR

TR

20:2

5.80

^0.

02a

4.29

^0.

07b

5.48

^0.

06c

3.74

^0.

04d

5.24

^0.

15e

2.70

^0.

02f

2.77

^0.

05f

2.75

^0.

01f

3.99

^0.

01g

5.04

^0.

08h

20:4

n-6

8.24

^0.

03ac

1.41

^0.

02b

8.45

^0.

20a

1.52

^0.

04b

7.99

^0.

06ce

3.46

^0.

03d

7.75

^0.

15e

3.29

^0.

02d

17.2

4^

0.21

f7.

16^

0.12

g

20:5

n-3

16.0

9^

0.35

ac

13.5

1^

0.41

b15

.75^

0.16

ac

14.8

6^

0.10

cf21

.44^

0.62

d9.

90^

0.09

e16

.30^

0.91

a13

.88^

0.06

fb19

.00^

0.10

g21

.66^

0.57

d

22:6

n-3

20.7

0^

0.52

a13

.87^

0.16

b27

.15^

0.21

c14

.65^

0.45

b32

.65^

0.67

d20

.07^

0.58

a24

.64^

1.22

e15

.25^

0.35

b27

.26^

0.67

c7.

92^

0.13

f

Notes:

Mea

ns

foll

owed

by

dif

fere

nt

lett

ers

inth

esa

me

lin

ear

est

atis

tica

lly

dif

fere

nt

(p,

0.05

)b

yT

uk

ey’s

test

;MM

,mal

em

uss

el;F

M,f

emal

em

uss

el;

SQ

,sq

uid

;O

Y,

oyst

er;

OC

,oc

top

us;

NL

,n

eutr

alli

pid

s;P

L,

pol

arli

pid

s;T

R,

trac

e;d

ata

are

pre

sen

ted

asm

ean^

SD

Table II.Fatty acid composition(relative percentage) inNL and PL of samples

EPA and DHAin seafood

407

MM

MF

SQ

OY

OC

LN

A70

.77^

0.14

79.6

3^

0.91

TR

12.2

3^

0.40

TR

AA

73.1

3^

0.60

95.6

3^

1.05

41.1

2^

0.35

27.1

0^

1.15

103.

29^

1.30

DH

A34

0.76

^2.

4446

6.35

^4.

7612

2.83

^1.

0472

.25^

0.49

99.2

1^

6.37

EP

A42

8.40

^2.

8959

8.28

^7.

8931

2.90

^4.

8211

2.93

^0.

7217

6.01

^1.

90D

HA

þE

PA

769.

161,

064.

6343

5.73

185.

1827

5.22

Notes:

MM

,m

ale

mu

ssel

;M

F,

fem

ale

mu

ssel

;S

Q,

squ

id;

OY

,oy

ster

;O

C,

octo

pu

s;L

N,

neu

tral

lip

ids;

PL

,p

olar

lip

ids;

TR

,tr

ace;

dat

aar

ep

rese

nte

das

mea

n^

SD

Table III.Concentrations(100 mg g21 sample)of the main fatty acidsidentified in the samples

NFS41,6

408

References

AOAC (1998), Official Methods of Analysis of AOAC International, 16th ed., Association ofOfficial Analytical Chemists, Arlington, VA.

Bligh, E.G. and Dyer, W.J. (1959), “A rapid method of total lipid extraction and purification”,Canadian Journal of Physiology and Pharmacology, Vol. 37 No. 18, pp. 911-17.

Camargo, S.G.O. and Pouey, J.L.O.F. (2005), “Aquicultura – um mercado em expansao”,Revista Brasileira de Agrociencia, Vol. 11 No. 4, pp. 393-6.

Copeman, L.A. and Parrish, C.C. (2004), “Lipids classes, fatty acids, and sterols in seafood fromGilbert Bay, Southern Labrador”, Journal of Agricultural and Food Chemistry, Vol. 52No. 15, pp. 4872-81.

FAO FISHSTAT Plus (2007), Universal Software for Fishery Statistics Time Series, available at:http://ftp.fao.org/fi/STAT/summary/a1a.pdf/ (accessed 15 October 2009).

Graeve, M. and Janssen, D. (2009), “Improved separation and quantification of neutral andpolar lipid classes by HPLC-ELSD using a monolithic silica phase: application toexceptional marine lipids”, The Journal of Chromatography B, Vol. 877 Nos 20/21,pp. 1815-19.

Henderson, R.J. and Tocher, D.R. (1987), “The lipid composition and biochemistry of freshwaterfish”, Progress on Lipid Research, Vol. 26 No. 4, pp. 629-35.

Johnston, J.J., Ghanbari, H.A., Wheeler, W.B. and Kirk, J.R. (1983), “Characterization of shrimplipids”, Journal of Food Science, Vol. 48 No. 1, pp. 33-5.

Joseph, J.D. and Ackman, R.G. (1992), “Capillary column gas chromatography method foranalysis of encapsulated fish oil and fish oil ethyl esters: collaborative study”, Journal ofAOAC International, Vol. 75, pp. 488-506.

Kris-Etherton, P.M., Harris, W.S. and Appel, L.J. (2002), “Fish consumption, fish oil, omega-3 fattyacids and cardiovascular disease”, Circulation, Vol. 106, pp. 2747-57.

Maia, E.L. and Rodriguez-Amaya, D.B. (1992), “Fatty acid composition of the total,neutral and phospholipids of the Brazilian freshwater fish Colossoma macropomum”,in Charalambous, G. (Ed.), Food Sciences and Human Nutrition, Elsevier, London,pp. 633-42.

Martin, C.A., Almeida, V.V., Ruiz, M.R., Visentainer, J.E.L., Matsushita, M., Souza, N.E.and Visentainer, J.V. (2006), “Acidos graxos poliinsaturados omega-3 e omega-6:importancia e ocorrencia em alimentos”, Revista de Nutricao, Vol. 19 No. 6, pp. 761-70.

Navarro, J.C. and Villanueva, R. (2000), “Lipid and fatty acid composition of early stages ofcephalopods: an approach to their lipid requirements”, Aquaculture, Vol. 183 Nos 1/2,pp. 161-77.

Navarro, J.C. and Villanueva, R. (2003), “The fatty acid composition of Octopus vulgarisparalarvae reared with live and inert food: deviation from their natural fatty acid profile”,Aquaculture, Vol. 219 Nos 1-4, pp. 613-31.

Ozogul, Y., Duysak, O., Ozogul, F., Ozkutuk, A.S. and Tureli, C. (2008), “Seasonal effects in thenutritional quality of the body structural tissue of cephalopods”, Food Chemistry, Vol. 108No. 3, pp. 847-52.

Ozyurt, G., Duysak, O., Akamca, E. and Tureli, C. (2006), “Seasonal changes of fatty acids ofcuttlefish Sepia officinalis L. (Mollusca: Cephalopoda) in the northeastern Mediterraneansea”, Food Chemistry, Vol. 95 No. 3, pp. 382-5.

Ruxton, C.H.S. and Derbyshire, E. (2009), “Latest evidence on omega-3 fatty acids and health”,Nutrition & Food Science, Vol. 39 No. 4, pp. 423-38.

EPA and DHAin seafood

409

Simopoulos, A.P. (2002a), “Omega-3 fatty acids in wild plants, nuts and seeds”, Asia PacificJournal of Clinical Nutrition, Vol. 11, pp. S163-S73.

Simopoulos, A.P. (2002b), “The importance of the ratio of omega-6/omega-3 essential fatty acids”,Biomedicine & Pharmacotheraphy, Vol. 56 No. 8, pp. 365-79.

Simopoulos, A.P. (2004), “Omega-6/omega-3 essential fatty acid ratio and chronic diseases”, FoodReviews International, Vol. 20 No. 1, pp. 77-90.

Sirot, V., Oseredczuk, M., Bemrah-Aouachria, N., Volatier, J.-L. and Leblanc, J.-C. (2008), “Lipidand fatty acid composition of fish and seafood consumed in France: CALIPSO study”,Journal of Food Composition and Analysis, Vol. 21 No. 1, pp. 8-16.

Statsoft (1996), Statistica 5.1 Software, Statsoft, Tulsa, OK.

Stowasser, G., Pierce, G.J., Moffat, C.F., Collins, M.A. and Forsythe, J.W. (2006),“Experimental study on the effect of diet on fatty acid and stable isotope profiles of thesquid Lolliguncula brevis”, Journal of Experimental Marine Biology and Ecology, Vol. 333No. 1, pp. 97-114.

Talab, H.A., Ardjmand, M., Motallebi, A. and Pourgholam, R. (2010), “Extraction and purificationof omega-3 fatty acids concentrate from Hypophthalmichthys molitrix oil”, Nutrition & FoodScience, Vol. 40 No. 2, pp. 193-203.

Visentainer, J.V. and Franco, M.R.B. (2006), Acidos Graxos em oleos e Gorduras: Identificacao eQuantificacao, Varela, Sao Paulo.

Visentainer, J.V., Souza, N.E., Makoto, M., Hayashi, C. and Franco, M.R.B. (2005),“Influence of diets enriched with flaxseed oil on the a-linolenic, eicosapentaenoicand docosahexaenoic fatty acid in Nile tilapia (Oreochromis niloticus)”, Food Chemistry,Vol. 90 No. 4, pp. 557-60.

Wang, Y.J., Miller, L.A., Perren, M. and Addis, P.B. (1990), “Omega-3 fatty acids in lake superiorfish”, Journal of Food Science, Vol. 55 No. 1, pp. 71-3.

Zlatanos, S., Laskaridis, K., Feist, C. and Sagredos, A. (2006), “Proximate composition, fatty acidanalysis and protein digestibility-corrected score of three Mediterranean cephalopods”,Molecular Nutrition & Food Research, Vol. 50 No. 10, pp. 967-70.

Further reading

Institute of Medicine (2008), Dietary Reference Intakes (DRis) for Energy, Carbohydrate, Fiber,Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. Part 1, National Academy Press,Washington, DC.

About the authorsElton Bonafe holds a Bachelor’ degree in Chemistry from State University of Maringa (UEM),a Master’s degree in Analytical Chemistry Applied to Food, and is currently a doctoral studentat EMU.

Ana de Aguiar, graduated in Food Engineering from Universidade Estadual de Maringa(UEM) and is working towards a Master’s at Universidade Federal de Santa Catarina,UFSC. Ana de Aguiar is the corresponding author and can be contacted at:aguiarea@gmail.com

Marcela Boroski, graduated with a Bachelor’ degree in Chemistry from State University ofMaringa (UEM), holds a Masters in Analytical Chemistry and is currently a doctoral student atEMU.

Johny Monteiro has a graduate degree in Chemistry from State University of Maringa (UEM)and is currently a graduate student from the same institution.

NFS41,6

410

Nilson Souza, Professor, State University of Maringa (UEM), graduated in Chemistryfrom Union (EMU), is a Master in Food Science, from the University Of Londrina (UEL), and is aDoctor of Science, from State University of Campinas.

Makoto Matsushita, Professor at State University of Maringa (UEM), is a Doctor of Sciences(EMU), and is working in the area of Food Science and Technology.

Jesuı Visentainer, Associate Professor of EMU, graduated in Chemistry from State Universityof Maringa (UEM), is a Master of Science and Food Technology, Federal University of Vicosa(UFV), and has a PhD in Food Science from the University of Campinas. He is currentlya Member of the Advisory Committee (APCs) of the Araucaria Foundation – Parana.

To purchase reprints of this article please e-mail: reprints@emeraldinsight.comOr visit our web site for further details: www.emeraldinsight.com/reprints

EPA and DHAin seafood

411