ArticlePDF Available

Prevalence of Pathogenic Bacteria in Shrimp Samples Collected from Hatchery, Local Markets and the Shrimp Processing Plant

Authors:

Abstract and Figures

Export quality frozen shrimps comprise as one of the major economic interests in Bangladesh. During cultivation or processing and packaging, microbial condition is an important issue to maintain the quality of shrimps. Eight shrimp samples, of which, one from hatchery, 3 from local markets and 4 processed export quality samples were studied for microbiological risk assessment (MRA). One hatchery, three market and two export quality shrimp samples were found to contain bacterial pathogens probationary identified as Escherichia coli, Klebsiella spp., Vibrio spp., Aeromonas spp., Pseudomonas spp., Listeria spp., Shigella-like organisms, Staphylococcus aureus, and Salmonella spp. and two other processed export quality shrimp samples were completely free of pathogens of any type. Surprisingly, the later two processed export quality shrimp samples showed antibacterial activity against E. coli, Klebsiella sp. and Vibrio sp.Bangladesh J Microbiol, Volume 29, Number 1, June 2012, pp 7-10
Content may be subject to copyright.
Introduction
Shrimp cultivation and export in Bangladesh have undergone
rapid expansion over the last two decades. Between 1983 and
2003, the volume of shrimp and prawn cultivated in land
aquaculture
has increased more than 14 times1. In 2003, the Department of
Fisheries estimated that there had been approximately 203,071
hectares of coastal shrimp farms producing an average of 75,167
metric tons of shrimp annually1. Export of shrimps has given
second priority in terms of earning foreign currency after the
garment industry.
Currently, 36 shrimp species are harvested and cultivated in
Bangladesh. The two main species of shrimps are the bagda
(shrimp) and the golda (prawn). Chittagong-Cox’s Bazar and
Khulna-Shatkira-Bagherat regions usually dominate shrimp
production. These two regions account for approximately 95
percent of the total area dedicated to shrimp culture. Brackish
water aquaculture is widespread throughout Satkhira, Khulna,
Cox’s Bazar, and Bagerhat. Penaeus monodon and
Macrobrachium rosenbergii, the two major species of bagda
and golda, respectively, are cultivated in these areas.
Macrobrachium rosenbergii, the most popular freshwater
prawn, is largely produced in the southwest region of the country.
There has been an increase in awareness about the nutritional
value and health benefits of fish consumption in the last two
Original Article
Bangladesh J Microbiol, Volume 29, Number 1, June 2012, pp 7-10
decades. On the other hand, seafood is also known to have been
responsible for a significant percentage of food-borne diseases2,
3. In the seafood related outbreaks, a wide variety of viruses,
bacteria, and parasites have been reported. Consumption of raw
or undercooked seafood is the factor most commonly
associated with infection4. There is epidemiological evidence,
particularly from Japan, that consumption of raw fish is indeed
the cause of many outbreaks of food-borne diseases. Biotoxins
and histamines make up a large proportion of these outbreaks5.
Though viruses are the most common cause of seafood related
infections, most of the hospitalisation and deaths are due to
bacterial agents4. As a consequence, food safety and quality
aspects in trade became important, since fresh food is more
prone to microbiological contamination6. Therefore, with the
growing importance of shrimp as one of the major export items
from Bangladesh, it is important to carefully maintain the
microbiological quality of the exported item through appropriate
measures.
In this perspective, we attempted to monitor the pathogenic load
randomly in export quality shrimps. However, microbiological
proliferation in the shrimp is mainly dependent on the condition
of transport, handling and processing. Frozen shrimps are often
contaminated after catching7. Handling of raw materials
influences the bacteriological quality of frozen shrimps.
Insufficiently iced and improperly storage of shrimps at higher
temperature enhances the growth of microorganisms
Prevalence of Pathogenic Bacteria in Shrimp Samples Collected from
Hatchery, Local Markets and the Shrimp Processing Plant
M. Majibur Rahman, Farjana Rahman, Farzana Afroze, Farzana Yesmin, Kazi Kaniz Fatema, Kamal Kanta
Das, Rashed Noor*
Department of Microbiology, Stamford University Bangladesh, 51 Siddeswari Road, Dhaka-1217, Bangladesh.
Export quality frozen shrimps comprise as one of the major economic interests in Bangladesh. During cultivation
or processing and packaging, microbial condition is an important issue to maintain the quality of shrimps. Eight
shrimp samples, of which, one from hatchery, 3 from local markets and 4 processed export quality samples were
studied for microbiological risk assessment (MRA). One hatchery, three market and two export quality shrimp
samples were found to contain bacterial pathogens probationary identified as Escherichia coli, Klebsiella spp., Vibrio
spp., Aeromonas spp., Pseudomonas spp., Listeria spp., Shigella-like organisms, Staphylococcus aureus , and Salmonella
spp. and two other processed export quality shrimp samples were completely free of pathogens of any type.
Surprisingly, the later two processed export quality shrimp samples showed antibacterial activity against E. coli,
Klebsiella sp. and Vibrio sp.
Key Words: Shrimp; pathogenic microorganisms; export quality frozen shrimp, antimicrobial activity
*Corresponding author:
Dr. Rashed Noor, Department of Microbiology, Stamford University Bangladesh, 51 Siddeswari Road, Dhaka-1217,Tel: 8355626, 8355596 ext. 472, Cell: +8801749401451, E-mail:
noor.rashed @yahoo.com
responsible for microbiological changes. Thus, the quality of
shrimp and frozen fish of desirable food standards has to be
ensured with necessary measures. Frozen shrimps are normally
subjected to preshipment inspection based on physical and
sensory characteristics followed by microbiological
characteristics. Thus, our study was designed to i) identify and
enumerate the pathogens associated with the shrimps dedicated
for export, with the shrimps from hatchery and from local
markets; ii) to compare the microbiological data among the
various shrimp samples studied; and iii) finally to assess whether
is any residual antimicrobial agents left in the sample even after
processing.
Materials and Methods
Sample Collection
Export quality frozen shrimp samples were collected from
Conception Sea Food Ltd., Cox’s Bazar and Seamark (BD)
Limited, Chittagong, Bangladesh. Hatchery shrimp was
collected from Shatkhira, Khulna. Market shrimps were
collected from Malibagh bazaar, Shantinagar market and Agora
departmental store. One fresh (Macrobrachium rosenbergi,
sample code ES 4), 2 sea water (Penaeus monodon, sample
code ES 1, 2 & 3) export quality frozen shrimp samples, 1
hatchery and 3 market shrimp samples were subjected to
microbiological testing.
Sample Processing
Ten grams of samples from different parts (head, body and head
body) of each shrimp were aseptically collected and were
transferred to sterile containers. The sample was transferred to
90 ml sterile normal saline and was homogenized. Then 1 ml of
the homogenized suspension was transferred to 9 ml normal
saline and then serial dilution (10-fold) was carried out up to
10 6 consecutively.
Isolation of pathogenic microorganisms from shrimp sample
Escherichia coli and Klebsiella spp.
To isolate Escherichia coli and Klebsiella spp. from each 10-1
to 10-3 dilution tubes, 0.1 ml suspension was spread on the
surface of MacConkey agar medium and was incubated at 37
°C for 24 h. After incubation, the plate was observed for
characteristic colonies. The presence of E. coli was further
confirmed by the appearance of bluish-black colonies with
green metallic sheen on Eosin-Methylene Blue (EMB) agar
medium.
Salmonella spp., Shigella-like organisms and Vibrio spp.
One ml of homogenized sample was transferred to 9ml of
selenite cystine broth and alkaline peptone water (10-1 dilution)
for enrichment of Salmonella, Shigella like organisms and
Vibrio spp., respectively, which were then incubated at 37 °C
for 6 h. Then 1 ml of enriched broth was subjected to 10-fold
serial dilution up to 10-2 to 10-6 in 9 ml of normal saline. From
each 10-4 to 10-6 dilution tubes, 0.1 ml of suspension was spread
onto XLD and TCBS agar plates. After incubated at 37 °C for
24 h, characteristic colonies were detected and counted.
Clostridium perfringens
Each sample was mixed in sterile saline in a ratio of 1:8 and
was heated at 80 °C for 15 minutes in order to kill vegetative
cells. Then 1 ml heated suspension was allowed to grow at 37°
C in 9 ml fluid thioglycolate broth for 4 hrs. Afterward, 1 ml of
enriched broth was subjected to 10-fold serial dilution from
10 1 to 10-6 in 9 ml of normal saline. From each 10-4 to 10-6
dilution tubes, 0.1 ml of suspension was pour plated on
perfringens agar medium. The plates were then incubated at 37
°C in a candle jar for 48 hrs. Colonies appeared as black were
detected and counted as suspected Clostridium perfringens.
Listeria monocytogenes
To isolate Listeria monocytogenes from 10-3, 10-5, 10-6 dilution
tubes, 0.1 ml suspension was spread onto Listeria isolation
media and was incubated at 37 ºC for 24 h. Colonies appeared
as olive green were detected and counted as suspected Listeria
monocytogenes.
Probationary identification of the bacterial isolates
Different types of colonies in various culture media were
observed carefully. Morphological characteristics including
color, shape, elevation, surface texture, opacity, etc of the
colonies on different media were recorded. The size and shape
of the cells were observed by Gram staining. Finally, according
to the Manual of Methods for General Bacteriology (ASM,
1981), a series of biochemical tests were performed to
probationary identify the bacteria of interest.
Tests for antimicrobial activity
Muller Hinton agar was seeded with test organisms (E. coli,
Klebsiella spp. and Vibrio spp.). Sterile paper discs (6.0 mm)
were impregnated each with 10 µl of homogenized shrimp
samples and were placed on the seeded agar plates. Plates were
then incubated at 37 oC for 24 h, and the clear zones of inhibition
(in mm) around the disc were measured with the slide calipers
and the results were recorded.
Results
Microbiological assessment of different samples (hatchery,
local market and processed export quality)
Presence of pathogenic microorganisms was examined through
the conventional cultural and biochemical methods. Various
types of selective media that encourage the growth of specific
microorganisms were also used. XLD agar was used for
Salmonella and Shigella, TCBS agar for Vibrio spp. and MSA
agar media was used for Staphylococcus spp. In XLD agar media,
black centered colonies were observed that were assumed as
Rahman et al.
08
Salmonella spp. In TCBS agar media green and yellow colonies
were observed. Yellow colonies were suspected as Vibrio
cholerae and green colonies were suspected as Aeromonas and
Vibrio parahaemolyticus as it had no ability to ferment sucrose
in the TCBS agar. Olive green colonies with black center hollow
were identified as Listeria spp. on Listeria identification agar
media. Colonies from different selective media were
subcultured and subjected to extensive biochemical test for
confirmation. Results are given in the Table 1.
Comparison among results of pathogenic bacteria isolated from
local market, hatchery and processed export quality frozen
shrimps (promoted)
A comparative study was carried out to assess the quality of
supplied shrimp samples collected from local markets, hatchery
and shrimp industries. Pathogenic microorganisms associated
with health hazards were probationary identified as E. coli,
Klebsiella spp., Vibrio spp., Listeria spp., Salmonella spp. and
Staphylococcus aureus. The results are summarized in Tables
1 & 2. A number of bacterial pathogens were found from shrimp
samples collected from different local markets and hatchery.
No pathogens were detected from processed export quality
frozen shrimp in samples 1 and 2. The higher pathogenic
bacterial load was observed in case of processed export quality
frozen shrimp samples 3 and 4.
Tests for antimicrobial activity
The complete absence of pathogens led us to assume that the
two processed export quality shrimp (ES1 & 2) samples might
consist of some chemicals inhibitory against pathogens. Thus,
we turned our interest to examine whether the sample contained
any antimicrobial agent. Thus, the shrimp samples were tested
against three common test organisms (E. coli, Klebsiella spp.
and Vibrio spp.). Complete zone of inhibition was observed
around test organisms after introduction of processed export
quality shrimp samples but no zone of inhibition was found in
case of hatchery shrimp (Table 3).
Table 1. Biochemical tests confirmative of the presence of the specific pathogens
Colonies on media TSI Catalase Oxidase Indole MR VP Citrate Suspected organism
Slant Butt Gas H2S test test production Utilization
Mac(Pink) A A + - + - + + - + E. coli
MacConky(Gummy) A A - - + + - - - - Klebsiella spp.
Listeria media (black) - - - - - - - - - - Listeria monocytogenes
TCBS (Large Yellow) A A + - + - + + - + Aeromonas spp.
TCBS(Small Yellow) A A - - + - + + - + Vibrio cholerae
TSI: Triple Sugar Iron A: Acidic Reaction
MR: Methyl Red K: Alkaline reaction
VP: Voges Praskeur + : Positive
- : Negative
Table 2. Comparison among the pathogenic load of the shrimp samples from market, hatchery and from processed export
quality frozen shrimps
Isolated Pathogenic Bacteria Count (cfu/g)
MB SM ADS ES-1 ES-2 ES-3 ES-4 HS
E. coli 8x1051.20x1061.00x1050 0 1x1041x1041.2x107
Kliebsiella spp 1x1050 0 0 0 4x1046.5x1052.0x107
Vibrio spp. 1.15x1061.26x1076.50x1050 0 3x1044.5x1052.9x105
Aeromonas spp. 0 0 0 0 0 0 0 2.7x105
Pseudomonas Spp. 0 0 0 0 0 0 0 5.5x107
Shigella like organisms 3.00x1062.00x1051.02x10700 0 0 0
Salmonella spp. 0 0 0 0 0 0 2x1040
Clostridium spp. 0 0 0 0 0 0 0 0
Staphylococcus aureus 4.58x1076.57x1072.09x1070 0 1.50x1071.01x1070
Listeria spp. 0 7.85x1070 0 0 3x1044.5x1053x107
MB: Malibagh Bazar SM: Shantinagar Market
ADS: Agora Departmental Store ES: Export Quality Frozen Shrimp
HS: Hatchery shrimp
Prevalence of Pathogenic Bacteria in Shrimp Samples Collected
09
Table 3. Antimicrobial activity exhibited by export quality
shrimp samples
Sample code Zone of Inhibition (mm) against pathogens
E. coli Klebsiella Vibrio
HS-1 Nil Nil Nil
ES-1 24 18 15
ES-2 19 17 12
HS: Hatchery shrimp
ES: Export quality frozen shrimp Nil: no zone of inhibition found around
the sample used
Discussion
Fisheries sector plays an important role in the socio-economic
development of Bangladesh. This is the second highest source
of earning foreign currencies and providing direct or indirect
employment to 10% of the total population of the country1.
The quality of the processed products largely depends on the
quality of raw materials and it is difficult to preserve freshness
of raw materials when there is a long gap between the harvesting
and processing time. During this period, shrimps continue to
deteriorate8. The time interval between the landings of shrimps
and their arrival at the processing plants is very important9.
Improper handling and inadequate processing result in microbial
growth which causes spoilage of food products. Present study
was thus carried out to assess the pathogenic load in the shrimp
samples of export quality.
Bangladesh exports mainly frozen shrimp and different types
of fresh and marine water fishes. The recent introduction of the
Hazard Analysis Critical Control Point (HACCP) system and
European Union hygienic regulations in seafood industries will
pave the way for the production of safe and high quality seafood.
Bangladesh frozen shrimp exporters continue to have both real
and perceived problems with buyers in the USA, the European
Union and Japan, concerning the safety and quality of their
products. Because many fish processing plants in Bangladesh
do not follow the HACCP system and EU hygienic regulations
for which many of them have been banned and the export of
shrimps, fish and fish products is reduced10. From the standpoint
of above observations, we have tried to assess the quality of our
shrimp products and our study detected the presence of
pathogens (Escherichia coli, Klebsiella spp., Vibrio cholerae,
Listeria monocytogenes) associated with enteric diseases in
human from shrimp sample collected from hatchery and market
which exceed the standard level of ICMSF (International
Commission on Microbial Specifications for Foods). Pathogens
were also identified from export quality shrimp samples which
may occur due to inadequate processing and transportation. Thus,
the presence of pathogens in shrimp samples suggests the fact
that proper handling and maintenance is necessary. Another
interesting finding of our study reveals that chemical
preservatives or antibiotics may be used by the shrimp
processing industries to maintain the standard quality. For
establishment of the significant validity of this test, further
chemical analysis will unveil the accuracy of shrimp processing
in future in Bangladesh.
Antimicrobial agents are being used worldwide in aquaculture
to present infection. The commonly used antibiotics are
sulphonamides, tetracycline, amoxicillin, trimethoprim-
sulphamethoxine and quinolones11. Our results also showed the
presence of antimicrobial agents in shrimp samples. However,
extensive biological and chemical characterization is required
to confirm the presence of a particular agent and its
concentration as high concentration of preservative of any type
is health hazardous.
Conclusion
Overall, according to the present study, shrimps of hatcheries
and local markets have been found to harbor many pathogens
indicating that these are not protected from contamination during
subsequent handling, packaging, storage, and transport.
Microbiological quality is a very vital aspect of quality control
measures; proper handling of fish between capture and delivery
to the consumer is a crucial element in assuring quality of the
final product. Standard sanitation, handling and the time &
temperature of holding fish are significant factors to ensure
quality. Properly controlled monitoring is also required for
transportation and storage. If HACCP guidelines are strictly
followed during processing and handling, the risk of
contamination and outbreak of diseases would be minimized.
References
1. DoF (Department of Fisheries). 2005. Fish Fortnight Compendium,
Department of Fisheries, Ministry of Fisheries and Livestock, Government
of the Peoples Republic of Bangladesh.
2. Karunasagar I, Pai R, Malathi GR and Karunasagar I. 1994. Mass mortality
of Penaeus monodon larvae due to antibiotic resistant Vibrio harveyi
infection. Aquaculture 128: 203-209.
3. Wallace BJ, Guzewich JJ, Cambridge M, Altekruse S and Morse DL. 1999.
Seafood-Associated Disease outbreaks in New York, 1980-1994. American
J Preventive Med. 17 (1): 48-54.
4. Butt AA, Aldridge KE and Sanders CV. 2004. Infections related to the
ingestion of seafood Part I: viral and bacterial infections. The Lancet Infect
Dis. 4: 201-212.
5. Huss HH. 1997. Control of indigenous pathogenic bacteria in seafood.
Food Control. 8(2): 91-98.
6. Sawhney A. 2005. Quality Measures in Food Trade: The Indian Experience.
The World Economy. 28 (3): 329-348.
7. Robinson RK. 1985. In Microbiology of Frozen Food. Elsevier Applied
Science Publishers.
8. Antony MM, Jeyasekaran G, Shakila RJ and Shanmugam SA. 2002.
Microbiological Quality of Raw Shrimps Processed in Seafood Processing
Plants of Tuticorin, Tamil Nadu, India. Asian Fish Sci. 15: 33-41.
9. Rajadurai NP. 1985. Improving the quality of shrimp through proper
handling. INFOFISH International. 1: 50-52.
10. CFC/INFOFISH. 1997. CFC/INFOFISH Project on Export Promotion of Value-
Added Fishery Products and their Sustainable Development. Progress
Report (1 January – 30 June 1997). Kuala Lumpur, Malaysia: INFOFISH.
11. Angulo F. 1999. Use of antimicrobial agents in aquaculture: potential for
public health impact. Division of Bacterial and Mycotic Diseases. Center
for Disease Control and Prevention. Accessed 24 August, 2007.
Rahman et al.
10
... While the larger counts were recorded for the wholesale and retail markets, the opposite was evidenced for the farm (gher) and processing plant, and this difference was statistically significant (p <0.05). Comparable microbial loads in retail shrimp markets were reported in several studies (Rahman et al. 2012;Yousuf et al. 2008). The higher bacterial loads (Table 4) as found in shrimp samples from the wholesale market was demonstrated with deteriorated sensory (Table 2) and nutritional (Table 3) properties of the respective sample indicating the likely reasons could be the poor personnel hygiene and sanitation, and poor post-harvest handling (Pinu et al. 2007), as it passed more supply chain actors. ...
... In addition to Escherichia coli, Klebsiella spp., Vibrio spp., Aeromonas spp. and Listeria spp, the presence of Pseudomonas spp in a shrimp processing plant in Bangladesh (Rahman et al. 2012) and marine shrimp of India (Lakshmi et al. 2013) were reported as causes of concern. Although reported less frequently, the presence of Ralstonia spp was evident in diseased Oreochromis niloticus (Nile tilapia) and Clarias gariepinus (African catfish) in Uganda (Wamala et al. 2018), placing it a potential pathogenic agent for fishes. ...
... While the larger counts were recorded for the wholesale and retail markets, the opposite was evidenced for the farm (gher) and processing plant, and this difference was statistically significant (p <0.05). Comparable microbial loads in retail shrimp markets were reported in several studies (Rahman et al. 2012;Yousuf et al. 2008). The higher bacterial loads (Table 4) as found in shrimp samples from the wholesale market was demonstrated with deteriorated sensory (Table 2) and nutritional (Table 3) properties of the respective sample indicating the likely reasons could be the poor personnel hygiene and sanitation, and poor post-harvest handling (Pinu et al. 2007), as it passed more supply chain actors. ...
... In addition to Escherichia coli, Klebsiella spp., Vibrio spp., Aeromonas spp. and Listeria spp, the presence of Pseudomonas spp in a shrimp processing plant in Bangladesh (Rahman et al. 2012) and marine shrimp of India (Lakshmi et al. 2013) were reported as causes of concern. Although reported less frequently, the presence of Ralstonia spp was evident in diseased Oreochromis niloticus (Nile tilapia) and Clarias gariepinus (African catfish) in Uganda (Wamala et al. 2018), placing it a potential pathogenic agent for fishes. ...
Article
Full-text available
Black Tiger Shrimp (Penaeus monodon) is one of the leading export commodities in Bangladesh. The industry, however, is frequently beset with quality deterioration and microbial diseases owing to various reasons. Here, we analyzed the sensory and nutritional qualities of shrimp, the total bacterial count, and molecular identification of pathogenic bacteria in samples collected from different supply chain actors (SCA), including the gher (farms), depots, wholesalers, retailers, and the processing industry in Khulna, Bangladesh. While the Sensory Quality Indices (SQI) of shrimps collected from farms, depots, and processing plants were found 'excellent and highly acceptable', the rating for wholesale and retail markets were 'good and acceptable'. Nutritionally, higher protein (21.59%), lipid (1.47%), and ash (1.97%) contents were found in shrimps collected from farms than that of other SCAs. Heterotrophic bacterial count (cfu/g) differed in various SCAs: farms 3.75±0.31 (×10 6), depots 3.95±0.92 (×10 6), wholesale markets 5.03±0.35 (×10 6), retail markets 4.82±0.40 (×10 6), and the processing industry 3.78±0.25 (×10 6). The presence of Ralstonia spp and Pseudomonas spp, confirmed by 16S rDNA sequencing were found in different SCAs. Overall, the quality of shrimp appeared better in farms than that of other SCAs, indicating that a lack of proper hygiene, sanitation, and post-harvest handling practices could be the likely impediments for quality deterioration.
... Lactic acid bacteria (LAB) and Clostridium perfringens counts were determined using de Man Rogosa and Sharpe agar and Perfringens agar medium supplemented with a soft double layer of Tryptic Soy agar and incubated in an anaerobic jar at 35°C and 37°C using a CO 2 in flux incubator (Binder Model C 170, Binder Inc., Bohemia, NY, USA), respectively, for 3 days (Olatunde et al., 2019). Black colonies grown on Perfringens agar medium indicated Clostridium perfringens (Rahman et al., 2016). ...
Article
Pacific white shrimp treated with pulsed electric field (PEF) and subsequently soaked in 1% Chamuang leaf extract (CLE) were packed under various modified atmospheres (MAP) including absolute N2, Ar or CO2. Lower melanosis score was evidenced in PEF pre-treated shrimp followed by soaking in 1% CLE and packing under CO2-MAP (PEF-CLE-CO2) than the control and other treated samples during storage at 4 °C (P < 0.05). PEF-CLE-CO2 showed lower pH, carbonyl content, total volatile base, peroxide value and thiobarbituric acid reactive substances but exhibited higher likeness scores (P < 0.05). Psychrophile, Enterobacteriaceae, Pseudomonas, lactic acid bacteria and H2S producing bacterial counts were less than 3 log CFU/g, which was lower than those of other samples at day 10 (P < 0.05). Oxidation of fatty acids (EPA and DHA) was prevented in PEF-CLE-CO2 than the control and other treated samples (P < 0.05). Volatile compounds in PEF-CLE-CO2 sample were negligible, compared to the control which was abundant in 3-methyl-1-butanol. Therefore, PEF and CLE treatment before MAP, especially under CO2 exhibited high efficacy in prolonging shelf-life of refrigerated shrimp.
... Lactic acid bacteria (LAB) and Clostridium perfringens counts were determined using de Man Rogosa and Sharpe agar and Perfringens agar medium supplemented with a soft double layer of Tryptic Soy agar and incubated in an anaerobic jar at 35°C and 37°C using a CO 2 in flux incubator (Binder Model C 170, Binder Inc., Bohemia, NY, USA), respectively, for 3 days (Olatunde et al., 2019a). Black colonies grown on Perfringens agar base indicated Clostridium perfringens (Rahman et al., 2016). ...
Article
High voltage cold atmospheric plasma (HV-CAP) using dielectric barrier discharge was implemented on Pacific white shrimp (PWS) pre-soaked with 0.5 or 1% Chamuang leaf extract (CLE). PWS were firstly packed under different gas ratios of Ar, O2 or air and then subjected to HV-CAP for 10 min. Lower melanosis scores were found in the samples treated with 1% CLE and HV-CAP in the presence of Ar and air (80:20) than the control and other samples throughout storage of 15 days at 4 °C (P < 0.05). Chemical quality changes in CP-Ar/Air-1 CLE sample were not significantly found at day 15. Those were evidenced by lower changes in pH (6.90), lower carbonyl content (2.41 μmol/mg protein), total volatile base (TVB) (17.81 mgN/100 g meat), peroxide value (4.21 mg cumene hydroxide/kg meat) and thiobarbituric acid reactive substances (TBARS) (2.35 mgMDA/kg meat) at the end of storage, compared to those of the control and other samples treated with 0.5% CLE and HV-CAP under different gas compositions at day 15 of storage (P < 0.05). Mesophilic bacteria, Pseudomonas, H2S-producing bacteria, Enterobacteriaceae, lactic acid bacteria and psychrophilic bacterial counts were less or equal to 5 log CFU/g meat in CP-Ar/Air-1 CLE sample, which were lower than the control and other treated samples at the end of the storage (4 °C) (P < 0.05). CP-Ar/Air-1 CLE sample also exhibited higher likeness scores for all the tested attributes, mostly associated with the reduced protein and lipid oxidation at the end of storage. After treatment, oxidation of polyunsaturated fatty acids (EPA and DHA) was lowered by 14.9% and 12.4% in CP-Ar/Air-1 CLE sample, compared to that found in the control (P < 0.05). Protein oxidation of HV-CAP treated sample was prevented by 1% CLE, irrespective of gas composition. Therefore, HV-CAP especially under the mixture of Ar and air along with high level of CLE, exhibited high efficacy in prolonging shelf-life of refrigerated (4 °C) Pacific white shrimp up to 15 days.
... 4). Similar types of bacteria were isolated by previous authors from shrimp, seafood and other fish sample [12,[23][24][25][26][27][28][29][30][31][32][33][34] . These results uncover that shrimp of this two processing plant had great exposure to foodborne microorganism. ...
Article
Full-text available
A total of 30 samples of shrimp were collected from two local sea food processing plant of Rupsha and Mongla Bazar of Khulna district to investigate the microbiological quality. Microbial quality was assessed by total viable count (TVC), total Vibrio count (TViC), total Staphylococcal count (TSC) and total E. coli count (TEC) by inoculating into specific media and the values of all the samples were ranged from log 2.92 to 3.41cfu/gm, log 2.06 to 2.11 cfu/gm, log 2.21 to 2.49 cfu/gm and log 2.14 to 2.22 cfu/gm respectively. Out of 30 samples 10, 11 and 5 samples were found positive for Vibrio spp., Staphylococcus spp. and. E. coli respectively. Results of antibiotic susceptibility test against eight commercially available antibiotics showed all three bacteria were multidrug resistant. This study revealed that the shrimp samples of Mongla contain higher load of bacteria than the samples from Rupsha.
Article
Vacuum impregnation-assisted penetration with Chamuang leaf extract (CLE; 1–2 g/100 ml) using 5 kPa 5 kPa absolute of vacuum, 7.5/15 min vacuum time and 15/22.5 min restoration time was studied in Pacific white shrimp subjected to prior pulsed electric field (PEF) before storage at 4 °C in modified atmosphere packaging (Ar/air; 80: 20). Lowest melanosis scores were obtained for samples treated with PEF (15 kV/cm, 800 pulses, 18 kJ/kg) and CLE (2 g/100 ml) with a 15 min vacuum time and 15 min restoration time and kept under an Ar/air atmosphere for 18 days. The control (untreated, kept in air) showed more melanosis during 18 days than treated samples (P < 0.05). Lower bacterial counts were attained in samples vacuum-impregnated with 2 g/100 ml CLE with prior PEF and stored under an Ar/air atmosphere (P < 0.05). These samples had lowest lipid oxidation, pH, total volatile bases and protein carbonyl content (P < 0.05). Higher liking scores for all attributes were noted in PEF-treated and vacuum-impregnated CLE (2 g/100 ml) samples. Thus, shrimp treated with CLE with the aid of combined processes and packaging had a shelf-life up to 18 days.
Article
Pulsed electric field (PEF) pre-treated Litopenaeus vannamei were immersed in Chamuang leaf extract (CLE) solutions (1 or 2%), followed by high voltage cold atmospheric plasma (HVCAP) in an argon/air (80:20) modified atmosphere for 10 min. Least melanosis scores were attained in the samples pre-treated with PEF (15 kV/cm, 800 pulses, 697 kJ/kg) and CLE (2%) prior to HVCAP compared to the untreated control, during 18 days at 4 °C (P < 0.05). The lowest microbial load and spoilage bacteria count (≤5 log CFU/g meat) were attained in PEF treated sample with 2% CLE followed by HVCAP (P < 0.05). Prior PEF sample in presence of 2% CLE showed lower peroxide value, thiobarbituric acid reactive substances, pH, total volatile base and protein carbonyl content than others (P < 0.05). Higher likeness scores were noted for all the attributes of the sample with prior PEF and 2% CLE sujected to HVCAP. Oxidation of polyunsaturated fatty acids and proteins was alleviated by CLE treatment. Phenolic compounds in CLE along with active species generated from HVCAP effectively inhibited microbial growth of L. vannamei during refrigerated storage. Thus, shelf-life of L. vannamei could be extended to 18 days using the the selected combined hurdle technologies, while the control (without treatment and kept in air) had the shorter shelf-life (9 days).
Article
Full-text available
The potential of aquaculture organism, Shrimp, need extra watchfulness to prevent it against the pathogenic bacteria attack. The use of synthetic antibiotics in shrimp can make pathogenic bacteria resistant and pollute the environment. Lately, Marine Natural Products (MNP) are other ways to overcome this problem. In this study, the MNP were extracted from macroalga Padina australis Hauck. The study aimed to examine the antibacterial activity of nhexane, ethyl acetate, acetone, and ethanol crude extract against three pathogenic shrimp bacteria(Vibrio harveyi, Vibrio parahaemolyticus, and Aeromonas hydrophilla) and phytochemical screening, respectively. Ethyl acetate crude extracts of Padina australis Hauck showed that it could act as an antibacterial agent against Vibrio harveyi (1,76 mm), Vibrio parahaemolyticus (2,3 mm) and Aeromonas hydrophilla (4,43 mm). The phytochemical tests revealed that P. australis Hauck contains a steroid, terpenoid, phenolic, tannin, and alkaloid compounds.
Article
Full-text available
Purpose – The purpose of this review is to narrate the microbiological quality of variety of street foods which are largely consumed by the Bangladeshi people of all ages. However, these foods are prone to microbial contamination. Most of the vendors lack the awareness on hygiene during preparing, processing or handling the foods. The insufficiency in regular microbiological analysis further casts the possibility of disease onset. The need of microbial analyses of these foods also remains unclear to the consumers, which, in turn, results in microbial infections and intoxications remaining unnoticed. Design/methodology/approach – The present review focused on the microbiological quality of the street foods projected from the locally conducted researches on street foods, and pondered on the possible management from a microbiological perspective for ensuring consumer safety. Findings – This paper provides comprehensive information on the microbiological quality of street foods, requirement of maintenance of hygiene by the vendors and consumers and the necessity of adopting proper management during food preparation. Originality/value – Demonstration of microbial prevalence in the street foods may bring imperative information on food safety and security. The conclusive message of this review is about the general consciousness on the microbiological aspects of street food contamination.
Article
The pathogenic bacteria indigenous to the aquatic and general environment are listed. Their distribution in nature, prevalence in seafood and the possibilities for growth of these organisms in various types of products are outlined. These data, combined with what is known regarding the epidemiology of disease, are used to place the various seafood products in risk categories and to identify areas of concern. It is concluded that the presence of pathogens in molluscs and the growth of Listeria monocytogenes in lightly preserved fish products are hazards which are presently not under control.In order to prevent growth and toxin production by Clostridium botulinum when products are stored at abuse temperature, it is recommended that additional barriers to growth are included in lightly preserved (e.g. cold smoked salmon) and low-heat treated (e.g. REPFEDS) products.It is finally pointed out that the Hazard Analysis Critical Control Point (HACCP) system is the preferred strategy in most quality assurance programmes and it is recommended that microbiological criteria are applied only as guidelines in the verification of the HACCP-system — and not for official control purposes.
Article
The cause of mass mortality in Penaeus monodon larvae in a hatchery was investigated. Antibiotic-resistant Vibrio harveyi could be isolated from all the infected larvae. These bacteria were absent in healthy eggs and nauplii. Although the intake seawater had V. harveyi, these strains were sensitive to antibiotics. The results suggest that antibiotic-resistant V. harveyi had been colonising larval tanks. The isolates from moribund larvae showed much lower LD50 values than isolates from natural seawater, thus indicating their higher virulence.
Article
Seafood-associated disease outbreaks in New York were examined to describe their epidemiology and to identify areas for prevention and control efforts. We reviewed reports submitted to the New York State Department of Health (NYSDOH) of seafood-associated outbreaks occurring from January 1, 1980, through December 31, 1994. During 1980-1994, 339 seafood-associated outbreaks were reported, resulting in 3959 illnesses, 76 hospitalizations, and 4 deaths. During this period, seafood-associated outbreaks accounted for 19% of all reported foodborne outbreaks and 10% of foodborne illnesses. Shellfish, the most frequently implicated seafood item, accounted for 64% of seafood outbreaks, followed by finfish (31% of outbreaks). Of the 148 seafood-associated outbreaks with a confirmed etiologic agent, Norwalk virus and scombrotoxin were the most frequently identified agents: Norwalk virus accounted for 42% of outbreaks and 42% of illnesses, and scombrotoxin accounted for 44% of outbreaks and 19% of illnesses. Three of the 4 seafood-associated deaths were caused by Clostridium botulinum; the remaining death was caused by Vibrio vulnificus. Reducing the number of seafood outbreaks will require continued and coordinated efforts by many different agencies, including those involved with water quality; disease surveillance; consumer education; and seafood harvesting, processing, and marketing. New York's foodborne disease surveillance data highlight potential areas on which to focus prevention efforts, including: (1) commodities and associated pathogens causing the largest number of seafood-associated outbreaks and illnesses, namely shellfish-associated viral gastroenteritis and finfish-associated scombroid fish poisoning, and (2) venues at which seafood were most frequently consumed in reported outbreaks, such as commercial food establishments and catered events.
Article
Foodborne diseases cause an estimated 76 million illnesses in the USA each year. Seafood is implicated in 10-19% of these illnesses. A causative agent can be traced in about 44% of seafood-related outbreaks, viruses accounting for around half of these illnesses. Although viruses are the most common cause of seafood-related infections, most hospitalisations and deaths are due to bacterial agents. A wide variety of viruses, bacteria, and parasites have been implicated in seafood-related outbreaks, which are reported worldwide. The factor most commonly associated with infection is consumption of raw or undercooked seafood. People with underlying disorders, particularly liver disease, are more susceptible to infection. The first part of this two-part review summarises the general incidence of seafood-related infections and discusses the common viral and bacterial causes of these infections. For each agent, the microbiology, epidemiology, mode of transmission, and treatment are discussed. In the May issue of the journal we will discuss parasites associated with seafood consumption, the safety of seafood, and the measures put in place in the USA to increase its safety.
Article
World trade in food has expanded significantly over the years and traditional tariff barriers have reduced with increasing commitments under the WTO. The industrialised countries potentially offer higher returns to food exporters from developing countries, but also pose a greater challenge in market access through stringent safety and quality standards. This paper analyses how this has impacted the Indian marine export industry, and the industry response to this challenge. The large firms are upgrading to signal quality in the OECD markets, while the small firms remain below the quality mark and are catering to other developing country markets where standards are not as stringent. Quality certification has thus become the basis of product differentiation and affected the pattern of trade. On the institutional front, a significant positive change is evident, with the Indian government taking measures to raise safety standards in the domestic food processing sector and increasing the credibility of its export certification agency abroad. There are also cooperative initiatives to improve testing facilities and promote equivalence of certification with OECD countries. The two-pronged approach of investment in upgrading the food processing industry and promoting international partnership in certification with destination markets offers a good model to address the continuous quality challenge facing other food exporting developing countries. Copyright Blackwell Publishing Ltd 2005.
Improving the quality of shrimp through proper handling. INFOFISH International
  • Np Rajadurai
Rajadurai NP. 1985. Improving the quality of shrimp through proper handling. INFOFISH International. 1: 50-52.
Department of Fisheries) Fish Fortnight Compendium, Department of Fisheries, Ministry of Fisheries and Livestock
  • Dof
DoF (Department of Fisheries). 2005. Fish Fortnight Compendium, Department of Fisheries, Ministry of Fisheries and Livestock, Government of the Peoples Republic of Bangladesh.
Use of antimicrobial agents in aquaculture: potential for public health impact. Division of Bacterial and Mycotic Diseases. Center for Disease Control and Prevention
  • F Angulo
Angulo F. 1999. Use of antimicrobial agents in aquaculture: potential for public health impact. Division of Bacterial and Mycotic Diseases. Center for Disease Control and Prevention. Accessed 24 August, 2007.