Although fish is rich nutrient source for mass people of Bangladesh, still
limited information available on the nutrient contents of edible marine fishes.
This study was conducted with the aim to estimate nutrient contents of some
selected major commercially important marine edible fishes Bay of Bengal. Proximate
composition and mineral content of five fish species viz. Pampus chinensis, Lates
Calcarifer, Johnius argentatus, Harpodon nehereus, Lepturacanthus savala were
determined. Proximate analysis revealed that moisture, protein, carbohydrate,
lipid, and ash ranged from 78.25±0.12 to 87.3±0.15%, 7.4±0.05 to 14.5±0.13%,
1.4±0.01 to 2.21±0.10% and 1±0.03 to 2.8±0.10% and the maximum content belonged
to H. nehereus, L. savala, P. chinensis, J. argentatus, L. savala respectively.
The mineral profiles showed that among macro minerals potassium was abundant
one followed by sodium, calcium, magnesium. Potassium, sodium, calcium,
magnesium content ranged from 198.199±0.22
to 700.218±0.15 mg, 190.743±0.10 to 466.733±0.35
mg, 40.182±0.13 to 200.113±0.27 mg, 130.784±0.24
to 152.577±0.22 mg per 100gm and maximum amount belonged to L. calcarifer, H. nehereus,
L. savala, P. chinensis respectively.
Major micro mineral was Iron followed by Zinc. Iron and Zinc content
varied from 2.769±0.06 to 8.603±0.66
mg, 1.130±0.03 to 2.799±0.07 mg per 100 gm
with maximum amount found in P. chinensis and H. nehereus respectively. Copper,
manganese, chromium, cadmium were found in very negligible amount. Cobalt and
Lead was absent. The potential contribution of each species to Recommended
Nutrient Intake (RNI) for adult (>18yr), pregnant and lactating woman (PLW),
infants (7 to 23 months) were calculated. P. chinensis and J. argentatus could
potentially contribute ?20% of the recommended nutrient intake of Iron and
magnesium for adult, PLW and infants from a standard portion and moreover
marine fish species shows good combination of protein and minerals. This study
might be helpful for better nutritional achievement in Bangladesh.
fish, proximate composition, mineral content, fatty acid profiles,Recommended
is consumed by large portion of population as they have good nutrition value.
In Bangladesh, fish is an incomparable animal-source food in the diet of
millions, both in terms of quantity and quality accounting for approximately
60% of animal protein intake at 18.1 kg consumed per person per year and the frequency
of consumption, far exceeding that of any other animal-source food 1. A wide
range of fishes (around 511 marine species) including shrimp is found in
Bangladeshi part of Bay of Bengal 2 which account for the 16.28% of the
national fish production 3. Essential amino acids are found in good
proportions in fish proteins. 4,5,6,7. eicosapentaenoic acid (EPA) and
docosahexaenoic acid (DHA) are also found in fish tissues 8,9 and these are
reported to play important role such as prevention of cardiovascular diseases,
cancers, rheumatoid arthritis, and inflammation 10,11. Many important body
functions such as acid-base balance, bone formation and catalyzemanymetabolic
reactions are the functions of minerals. ) 12, 13 and fish muscle and bones
are the good sources of essential minerals 14,15. In spite of the importance of marine fishes,
very limited information on the biochemical composition of marine fishes of Bay
of Bengal is available. Reports on the proximate composition on Dasyatis
americana, Dasyatis pastinaca, Dasyatis zugei and Gymnothorax favagineus are
only available 16.
objectives of this study was to evaluate the nutritive value of five
commercially important marine fish species viz.
Pampus chinensis, Lates Calcarifer, Johnius argentatus, Harpodon
nehereus, and Lepturacanthus savala
in terms of their proximate composition and mineral composition and in addition
to estimate their potential contribution to
recommended nutrient intakes (RNIs) during the first 1000 days of life
and for infants from age 7 to 23 months
Materials and Methods
2.1. Collection of Samples
Five marine fish SP (Pampus chinensis, Lates Calcarifer, Johnius
argentatus, Harpodon nehereus, Lepturacanthus savala) were collected from
Fishery Ghat, Chittagong; one of the most commercial landing centers of
Bangladesh during July 2015. From here marine fishes are supplied all over the
country. All samples were fresh fish and caught within 0 to 36 hours after
collection. All samples were immediately dipped into ice and transported in an
insulated ice box to Bangladesh Council of Scientific and Industrial Research (BCSIR),
Dhaka, Bangladesh. Upon arrival at BCSIR temperature of Ice box was checked to
ensure whether it is within -40C to 00C. Then total body
weight and length were measured for each sample. Then the samples were
beheaded, gutted, washed and filled. The duration of this study was from July
2015 to January 2016.
Table-1: Physical Characteristics of Fishes
Pampus chinensis (Euphrasen, 1788)
Lates calcarifer (Bloch, 1790)
Johnius argentatus (Houttuyn, 1782)
Harpodon nehereus (Hamilton, 1922)
Lepturacanthus savala (Cuvier, 1829)
2.2. Proximate Composition Analysis
Moisture content was determined
according to standard AOAC (1990) method 11 for which a known weight (10 ±
0.5 gm) of sample was placed in individual moisture basin and oven dried at 1050C
until constant weight was obtained. ………….reference????
Crude protein content was determined by
micro Kjeldahl method 12. Nitrogen content
was determined using a micro-Kjeldahl apparatus (Automatic Kjeldahl Digester, DKL
8 Series, VELP Scientifica, Italy and Kjeltec 2100, Distillation Unit, FOSS
Analytical, Denmark). Crude protein was estimated by multiplying nitrogen
content by 6.25………….reference????
Approximately 5±0.2 gm of dried sample
left after moisture determination was placed individually and kept in
pre-weighted conical flask was filled with 10ml of chloroform-methanol (2:1)
and kept for overnight. The solution was filtered and 0.50% NaCl solution
(20ml) was added and allowed to stand for 46hours. Extraction was carefully
collected and was evaporated to dryness at 1050C. Total lipid
content was determined gravimetrically13.
Total Carbohydrate and Energy were
determined by following equation:
Carbohydrate ? 100-(Moisture + Protein +Fat +Ash)
value K cal/100gm ? P×4.0 Protein K cal/100gm + F×9.0 Fat K cal/100gm +C×4.0
Carbohydrate K Cal/100gm. ………….reference????
2.3. Major Minerals Analysis
For mineral estimation, approximately
2±0.1 gm of wet sample were weighted into polypropylene screw capped tube and
10ml of concentrated HNO3 (65%) and 3ml of 60% per chloric acid were
added 14. it was left overnight to complete digestion. Then heating at 900C
for 7 hours was carried out I digestion chamber. After complete digestion,
digests were filtered out into 25ml volumetric flask and made up to volume with
ultra-pure water. After appropriate dilution Calcium Magnesium, Zinc, Iron,
Copper, Nickel were determined in Atomic absorption spectrometer (AAS) with
their standard solution by thermo scientific, iCE 3000 series, USA. All
chemicals and reagents used in the analysis procedure were of analytical grade
and purchased from Merck (Germany), BDH (UK) Sigma Chemical Co (St. Louis, MO,
2.4. Presentation of results
All proximate components and minerals
were analyzed in triplicates and presented here as the mean, reported to the
same number of significant figures as per original analytical results. All
minerals were reported in metric units per kg of raw, edible parts but are
presented here as metric units per 100 g raw, edible parts for ease of use.
Some nutrients are expressed as BDL (Below Determination Level).
2.5. Statistical analyses of results
Variations in growth and
fatty acid composition of fish were analysed using one?way ANOVA followed by Tukey’s HSD post
hoc for multiple comparisons. Data were presented as mean ± SEM and evaluated
by using the statistical software
package of SPSS for Windows version 20.0 (SPSS, Inc) with the
level of significance at p< 0.05. Microsoft Office Excel 2007 was used to make graphs. 2.6. Calculation of potential contribution to recommended nutrient intakes The potential contribution of each species to RNIs of nutrients of interest during the first 1000 days was calculated first by assigning an average RNI target for each nutrient for pregnant and lactating women (PLW) to account for variations in requirements throughout the three trimesters of pregnancy and first 12 months of lactation, and for infants to account for variations in requirements throughout the period from age 7 to 23 months 15,16; then by calculating the contribution from a standard portion of each species (50 g/day for PLW and 25 g/day for infants) as a percentage of the average RNI. The nutrients of interest considered here are iron, zinc, calcium. The RNIs for iron and zinc further vary according to estimated overall dietary bioavaibility which is dependent on a number of factors including the presence of animal-flesh foods, phytates and other factors; and are therefore provided according to four and three dietary bioavailability categories, respectively. The typical Bangladeshi diet based on polished rice, fish and vegetables is assumed to fit best with criteria used to define the '10% bioavailability' category for iron, and 'moderate bioavailability' category for zinc 15,16. III. Result and Discussion 3.1 Proximate composition The maximum (87.3±0.15%) moisture content was determined in Harpodon nehereus followed by Lates calcarifer (80.9±0.10%) while the lowest moisture content (78.25±0.12%) was determined in P. chinensis. Ash is a measure of the mineral content in fish. The highest ash content was determined in Johnius argentatus (2.8±0.10%) and the lowest was in Harpodon nehereus (1±0.03). Lipid content was ranged from 1.4 to 2.21% found in L. savala and P. chinensis respectively. For moisture (%), protein (%), Ash (%) content there was no significance difference was found among five fish species from ANOVA at 5% significance level (p<0.05). But fat content was found significantly different from ANOVA at 5% significance level (p<0.05). Fat generally varies much more widely than other proximate components of fish, and usually reflects differences in the way lipid is stored in particular species but may also be affected by seasonal/lifecycle variations and the diet/food availability of the species at the time of sampling 17. For example, bottom dwelling species such as the indigenous major carps are typically lean fish, storing fat in the liver 17, whereas, migratory fish such as Hilsa have a higher content of dark muscle which tends to be rich in fat 18. The total Protein content in fish species ranged from 7.4-14.5% found in H. nehereus and L. savala respectively. The RNI (Regular Nutrient Intake) of protein for 60kgs Body weighted person need 50gm protein/day 19. In Bangladesh mean intake of Fish is 50g/p/day according to desirable dietary pattern for Bangladesh 20. So 50gm of P. chinensis , Lates calcarifer , J. argentatus , H. nehereus , L. savala could fulfill 14.1%, 14%, 12.1%, 7.4%, 14.5% respectively to the daily requirement of protein. Sl. No. Fish sp. Proximate analysis Moisture Ash Lipid Protein Energy % K cal /100gm 1. P. chinensis 78.25±0.12 1.651±0.07 2.21±0.10 14.1±0.17 93.13 2. L. calcarifer 80.9±0.10 2.8±0.10 2.1±0.07 14±0.12 80.3 3. J. argentatus 79.7±0.20 1.15±0.05 2.2±0.05 12.1±0.03 81 4. H. nehereus 87.3±0.15 1±0.03 1.7±0.02 7.4±0.05 54.7 5. L. savala 78.46±0.16 1.231±0.05 1.4±0.01 14.5±0.13 89.2 Table- 2: Proximate Composition of Selected Fish Species (p<0.05) 3.2. Mineral composition Major mineral composition for all species are shown in table 3 3.2.1. Iron Iron is an important micro mineral. Deficiency of Iron is associated with anemia and thus with reduced working capacity and impaired intellectual development. The range of Iron content was considerably varied from 2.769±0.06 to 8.603±0.66 mg/100gm with a mean value of 6 mg/100 gm. The highest Iron content was found in P. chinensis that may fulfill >25% of the RNI and lowest amount was found
in J. argentatus that may
fulfill around 10% of the RNI for adult, PLW and infants. All fish species
without J. argentatus and L.
savala may fulfill >15% of daily requirement of Iron for adult, PLW and
infants. so these species can be served as good dietary source of Iron. This
may have implications on public health issue of Iron deficiency in Bangladesh
where 10.7% in preschool aged children and 7.1% in adult women are
prevalent 21 that have the impact on physical and mental development,
pregnancy complications, pre-term birth, and mortality.
Table- 3: Major Mineral Composition of Selected Fish Species
Zinc concentration varied considerably
from 1.130±0.03 to 2.799±0.07 mg/ 100 g with a mean content of 1.96 mg/100 g.
These results are within the range of fish and seafood reported elsewhere 22.
It is harmful for human body if zinc concentration is above than 3mg/100gm 23
but in the result zinc is clearly below the permissible limit for human
consumption. Zinc is essential for good health, but very high intakes can cause
health problems such as liver and kidney damage 24. The highest zinc
concentration was found in H. nehereus
that may fulfill 20% of the RNI of Zinc for adult and 17% for PLW and infants.
The lowest amount of Zinc was found in L. calcarifer that may fulfill ?7% of the RNI for
adult, PLW and infants. All fish species without L. calcarifer may fulfill
>10% of daily requirement of zinc for adult, PLW and infants from
a standard portion. In
light of recent estimates of a national prevalence of zinc deficiency in 57.3%
of women and 44.6% of pre-school aged children in Bangladesh 21, H. nehereus, by J. argentatus, P. chinensis, L. savala
could contribute significantly to dietary zinc intake, also taking into
consideration that zinc in animal-source foods is highly bioavailable 15,16.
content was ranged considerably from 40.182±0.13 to 200.113±0.27 mg/ 100 g with
a mean content of 120.15 mg/100 g. These results were within the range of fish
and seafood reported 22. The highest and lowest calcium content was found in L. savala and L. calcarifer respectively that would fulfill around 10% and 2% of
the RNI of calcium for adult, PLW and infants accordingly. Four other fish
species except L. calcarifer may
fulfill >5% of the RNI of calcium for adult, PLW and infants. Due to calcium
deficiency rickets develops, and it was estimated to affect 550,000 children in
2008 25, and in a study in two rural sub districts of Bangladesh, it was
estimated no women or young children had diets adequate in calcium,
attributable to low food intake and low dietary diversity 26. Marine fishes
are not one of the excellent sources of calcium because of they are not
consumed with bone only edible portion (muscle) are consumed.
is an important macro mineral. It needs to maintain for bone health, is
required for energy metabolism, and acts as a part of the protein-making
machinery. Magnesium content was ranged considerably from 130.784±0.24 to 152.577±0.22
mg/ 100 g with a mean content of 141.7 mg/100 gm. These results were within the
range of fish and seafood reported before 22. The highest and lowest
magnesium content was found in P.
chinensis and L. savala
respectively. Total five species may contribute ?25% of the daily magnesium
requirement of adult and PLW and ?60% of infant’s requirement from standard
portion. So these five marine fishes were excellent sources of magnesium.
is one of the macro minerals. Potassium is indeed to synthesis protein and
muscle tissue. Heart activity depend on Potassium as does muscle contraction.
Potassium content was varied from 198.199±0.22to 700.218±0.15 mg/100gm. Highest
amount was found in L. calcarifer. L. calcarifer, J. argentatus and P. chinensis may would fulfill
>5% of RNI for adult and PLW and >20% for infants.
Please write scientific name of the fishes in Bracket in
contribution to daily nutrient requirement for mineral from a standard serves
of fish for adult.
(a) Daily average nutrient requirement of Adult (>18yr) for Magnesium,
Calcium, Zinc, Iron is 260, 1000, 7, 13.7 mg/day respectively. (BIRDEM, 2013).
(b) Standard serve of fish for adult is 50g/day.
Fig. 2 Potential contribution to daily nutrient
requirement for mineral from a standard serves of fish for PLW.
(a) Daily average nutrient requirement of PLW for Magnesium, Calcium, Zinc,
Iron is 260, 1040, 7.9,15 mg/day respectively (FAO, 2004).
(b)Standard serve of fish for PLW is 50g/day.
(c) PLW, pregnant and lactating women.
regulates the electrolyte and acid-alkali balances, the conductive capacity of
the nerves, muscle contractions and the production of adrenaline and amino
acids. Sodium content was varied from 190.743±0.10 to 466.733±0.35 mg/100gm.
Highest sodium content was found in H.
nehereus followed by P. chinensis, J.
argentatus, L. savala, L. calcarifer More
uptake of Sodium is not good for health. The RDA for Sodium is up to 1500mg/day
to adult the result is within the range. In marine fish sodium is much higher
may be due to salt concentration. The highest sodium content was found in P.
chinensis and J. argentatus this may be due to their habitat, food
Fig. 4 Potential
contribution to daily nutrient requirement for mineral from a standard serves
of fish for infants.
(a) Daily average nutrient requirement of infant (7-23 month) Magnesium,
Calcium, Zinc, Iron is 54, 467, 4.1,7 mg/day respectively (FAO, 2004)
(b) Standard serve of fish for infant is 25g/day.
Manganese and Copper was present very lower in amount as trace
elements in fish. The permissible limit for Manganese is 0.54mg/100gm and
Copper is 1mg/100gm 27, the result is within the limit.
Chromium, Cadmium, Nickle, Cobelt, Lead
Chromium content was found from 0.353±0.06 to 0.564±0.05 mg/100gm.
That is quite similar the findings 28. More chromium contained indicates
environmental pollution as chromium content was very low in amount it indicates
the environmental condition of the area of fishing was good. Cadmium
concentration was found in vey lower in amount 0.018±0.01 to 0.292±0.02 mg/100gm. It
may be noted that cadmium was absent in L.calcarifer. According to FAO (1983) the
permissible limit of cadmium is 0.5mg/100gm. The result is below the range of
permissible limit. Cadmium is a toxic metal that can be present in fish
organism at high concentrations 29. In this Experiment Cobalt and Nickel are totally
absent in all of the fish samples. Only Nickel was present In H. nehereus is
0.1±0.02 mg/100gm and L. savala 0.022±0.01 mg/100gm which indicates the
pollution status of the source may be low or accumulation of metals was within
the limit of acceptance.
From the comparison of nutritional composition
of studied fish samples it is evident that marine fishes are good sources of
essential nutrients specially iron, zinc, magnesium. P. chinensis and J.
argentatus is very rich in protein, energy and essential minerals whereas
it may contribute significantly ?20% of RNI and H. nehereus may fulfill ?15% of the RNI of iron and magnesium
whereas maximum zinc content was found in H.
nehereus and it could fulfill ?20% of the daily requirement of zinc for
adult, PLW and infants. Total five fish species may significantly contribute
>25% of the RNI of magnesium for both adult and PLW and >60% for infants.
Marine fish does not exhibit calcium