Pharmacokinetics and residues of florfenicol in Nile tilapia (Oreochromis niloticus) post-oral gavage.

In the study on Oreochromis niloticus, singular oral gavage of florfenicol (FFC) at 15 mg/kg biomass/day was conducted, mimicking approved aquaculture dosing. Samples of plasma, bile, muscle, intestine, skin, liver, kidney, gill, and brain tissues were collected at 0, 2, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, and 128 hours (h) after oral gavage. LC-MS/MS analysis revealed FFC concentrations peaked at 12.15 µg/mL in plasma and 77.92 µg/mL in bile, both at 24 hours. Elimination half-lives were 28.17 h (plasma) and 26.88 h (bile). The residues of FFC ranked muscle>intestine>skin>liver>kidney>gill. In contrast, the residues of florfenicol amine (FFA) ranked kidney>skin>liver>muscle>gill>intestine>brain, particularly notable in tropical summer conditions. The minimum inhibitory concentration of FFC was elucidated against several bacterial pathogens revealing its superior efficacy. Results highlight bile's crucial role in FFC elimination. Further investigation, especially during winter when fish susceptibility to infections rises, is warranted.

AMR Threat Perception Assessment of Heterotrophic Bacteria From Shrimp Aquaculture Through Epidemiological Cut off Values.

BACKGROUND: Emergence and dissemination of antibiotic resistance is one of the major risks associated with the rampant usage of antibiotics in food-producing animals including aquaculture. OBJECTIVE: To determine Epidemiological Cut-OFF (ECOFF) values of heterotrophic bacterial populations from shrimp culture environments against five different antibiotics. METHODS: In this present study, bacterial samples were isolated from Penaeus vannamei culture environment in different locations of Andhra Pradesh, which is the aquaculture hub of India. The bacterial isolates were assessed for antibiotic resistance towards five antibiotics belonging to different classes (oxytetracycline, chloramphenicol, erythromycin, ciprofloxacin, and co-trimoxazole) by the disc diffusion method. Determination of Epidemiological Cut-OFF (ECOFF) values and analysis by employing normalized resistance interpretation (NRI) was carried out. RESULTS: The most dominant bacterial populations from shrimp culture were Vibrio spp. (pathogenic bacteria) followed by Bacillus spp. (probiotic bacteria). The bacterial isolates showed highest resistance towards oxytetracycline (overall 23.38%) and in location L6 (59.4%) followed by co-trimoxazole (31.1%). ECOFF values calculated by employing NRI showed that the disc diffusion data were distributed in a normalized manner. The maximum ECOFF value was obtained for ciprofloxacin (23.32 mm), while the minimum value was observed for oxytetracycline (9.05 mm). The antibiotic resistant phenotypes showed that the majority of the heterotrophic bacterial isolates (>60%) belonged to the non-wild type phenotype and primarily towards oxytetracycline (90%). CONCLUSION: The presence of non-wild antibiotic-resistant phenotypes of heterotrophic bacterial populations (which include not only pathogenic bacteria but also probiotic bacteria) indicates that shrimp culture ponds may be a reservoir for drug-resistant bacteria and there is a greater risk associated with transmission of resistant genes across bacterial flora. HIGHLIGHTS: NRI analysis of antibiotic disc diffusion data of heterotrophic bacterial populations in shrimp aquaculture environments revealed that majority of them belonged to non-wild type (90%) paticularly to oxytetracycline in comparison to other studied antibiotics (chloramphenicol, erythromycin, ciprofloxacin and co-trimoxazole).

Scope and challenges of seaweed utilization in food and nutraceutical industry in India: a review.

Seaweeds are an excellent source of unique antioxidant phytochemicals, dietary fibres, essential amino acids, vitamins, polyunsaturated fatty acids and minerals. The presence of such structurally diverse and high value bioactive compounds has led to popularization of seaweed as functional food ingredient in global health supplement market. India, with a long coastline of 8100 km and exclusive economic zone of 2.17 million km2, is rich in diverse seaweed resources belonging to almost 700 species. However, food and nutraceutical application of Indian seaweed is highly constrained. Apart from Kappaphycus alvarezii, there is no systematic commercial cultivation of seaweed in India. The regulatory framework for use of seaweed as food is still developing and consumer acceptance is still low. However, there is a timely and renewed interest from different government agencies and research organisations to develop a thriving food and nutraceutical industry using India's vast seaweed resources. The review briefly describes the nutritional and functional food potential of the seaweed and goes on to discuss the scope of seaweed utilization in food and nutraceutical industry in India. Further, the review has identified the regulatory challenges and quality control requirements for use of seaweeds in food and nutraceuticals.

Emergence of multidrug resistant, ctx negative seventh pandemic Vibrio cholerae O1 El Tor sequence type (ST) 69 in coastal water of Kerala, India.

Seventh pandemic Vibrio choleare O1 El Tor strain is responsible for the on-going pandemic outbreak of cholera globally. This strain evolved from non-pathogenic V. cholerae by acquiring seventh pandemic gene (VC 2346), pandemic Islands (VSP1 and VSP2), pathogenicity islands (VP1 and VP2) and CTX prophage region. The cholera toxin production is mainly attributed to the presence of ctx gene in these strains. However, several variants of this strain emerged as hybrid strains or atypical strains. The present study aimed to assess the aquatic environment of Cochin, India, over a period of 5 years for the emergence of multidrug resistant V. cholerae and its similarity with seventh pandemic strain. The continuous surveillance and monitoring resulted in the isolation of ctx negative, O1 positive V. cholerae isolate (VC6) from coastal water, Cochin, Kerala. The isolate possessed the biotype specific O1 El Tor tcpA gene and lacked other biotype specific ctx, zot, ace and rst genes. Whole genome analysis revealed the isolate belongs to pandemic sequence type (ST) 69 with the possession of pandemic VC2346 gene, pathogenic island VPI1, VPI2, and pandemic island VSP1 and VSP2. The isolate possessed several insertion sequences and the SXT/R391 family related Integrative Conjugative Elements (ICEs). In addition to this, the isolate genome carried virulence genes such as VgrG, mshA, ompT, toxR, ompU, rtxA, als, VasX, makA, and hlyA and antimicrobial resistance genes such as gyrA, dfrA1, strB, parE, sul2, parC, strA, VC1786ICE9-floR, and catB9. Moreover, the phylogenetic analysis suggests that the isolate genome is more closely related to seventh pandemic V. cholerae O1 N16961 strain. This study reports the first incidence of environmental ctx negative seventh pandemic V. choleare O1 El Tor isolate, globally and its presence in the aquatic system likely to induce toxicity in terms of public health point of view. The presence of this isolate in the aquatic environment warns the strict implementation of the epidemiological surveillance on the occurrence of emerging strains and the execution of flagship program for the judicious use of antibiotics in the aquatic ecosystem.

Safety, tolerability and biological responses of Oreochromis niloticus juveniles upon oral oxolinic acid administration.

In aquaculture, oxolinic acid (OA) is used as a second-line treatment at 12 mg/kg biomass/day for seven consecutive days. The present study evaluated the biosafety of 21 days of dietary administration of OA at 0, 12, 36, 60 and 120 mg by assessing the growth, biochemical, erythrocytic morphological and histopathological alterations and residue levels in Oreochromis niloticus. A significant dose-dependent reduction in feed intake and biomass and an increase in mortalities and erythrocytic cellular and nuclear changes were recorded. Significant elevations in plasma glucose, creatinine, alkaline phosphatase, alanine transaminase and aspartate transaminase and a decline in calcium and chloride levels were documented. The kidney, liver and intestine histoarchitecture showed mild to marked alterations. The edible tissue OA residues peaked on day 21 and decreased upon cessation of administration in all the dosing groups. The residue levels in the muscle of the recommended dose group were well within the maximum residue limit set by the European Medicines Evaluation Agency. Although the current study hinted at the safety and tolerability of OA even during long-term usage in O. niloticus in Indian conditions, care must be exercised for its aquacultural application because of its listing as a critically important medicine for humans.

Untargeted metabolomics reveals potential health risks associated with chronic exposure to environmentally relevant concentrations of 2-Phenylphenol.

Chronic exposure to endocrine-disrupting chemicals through foods of aquatic origin, at levels that are commonly found in the environment, can affect metabolic health and lead to metabolic diseases. One such chemical is 2-phenylphenol (2-PP), a suspected endocrine disruptor that is used extensively in agriculture and industry, and has become a widespread pollutant in aquatic environments. This study evaluated the risk of exposure to 2-PP through foods of aquatic origin from Vembanad Lake, using a Target Hazard Quotient (THQ) and an untargeted metabolomics approach. The study found that 2-PP content was higher in samples from areas with intense industrial, tourism, and agricultural activities. The average concentration of 2-PP in fish, crustaceans, and mollusks from the Vembanad estuary ranged from 0.012 to 0.017 mg/kg. The mean concentration of 2-PP was used to assess the THQ of exposure to the coastal population. The results showed that the THQ value was <1, indicating a low to moderate health risk for both adults and children. Furthermore, an untargeted metabolomics approach using HPLC-Q-Orbitrap MS was used to study the metabolome changes associated with chronic exposure to 2-PP (at the environmentally relevant concentration) over 60 days in the Wistar albino rat model. The findings indicated significant alterations in the phospholipid, fatty acid, sterol lipid, and amino acid profiles, suggesting that chronic exposure to 2-PP at environmentally relevant concentrations could affect purine, phenylalanine, tyrosine, and cholesterol metabolism.

Tetracycline resistance potential of heterotrophic bacteria isolated from freshwater fin-fish aquaculture system.

AIMS: This study investigated the tetracycline resistance potential of heterotrophic bacteria isolated from twenty-four freshwater fin-fish culture ponds in Andhra Pradesh, India. METHODS AND RESULTS: A total of 261 tetracycline resistant bacteria (tetR) were recovered from pond water, pond sediment, fish gills, fish intestine, and fish feed. Bacteria with high tetracycline resistance (tetHR) (n = 30) that were resistant to tetracycline concentrations above 128  µg mL-1 were predominantly Lactococcus garvieae followed by Enterobacter spp., Lactococcus lactis, Enterobacter hormaechei, Staphylococcus arlettae, Streptococcus lutetiensis, Staphylococcus spp., Brevundimonas faecalis, Exiguobacterium profundum, Lysinibacillus spp., Stutzerimonas stutzeri, Enterobacter cloacae, and Lactococcus taiwanensis. Resistance to 1024 µg mL-1 of tetracycline was observed in L. garvieae, S. arlettae, Enterobacter spp., B. faecalis. Tet(A) (67%) was the predominant resistance gene in tetHR followed by tet(L), tet(S), tet(K), and tet(M). At similar concentrations of exposure, tetracycline procured at the farm level (69.5% potency) exhibited lower inhibition against tetHR bacteria compared to pure tetracycline (99% potency). The tetHR bacteria showed higher cross-resistance to furazolidone (100%) followed by co-trimoxazole (47.5%) and enrofloxacin (11%). CONCLUSIONS: The maximum threshold of tetracycline resistance at 1024 µg mL-1 was observed in S. arlettae, Enterobacter spp., B. faecalis, and L. garvieae and tet(A) was the major determinant found in this study.

Impacts of Oral Florfenicol Medication and Residues on the Kidney and Liver of Nile Tilapia Oreochromis niloticus (L.)

Florfenicol (FFC), an approved aquaculture antibiotic, is administered in feed at doses of 10-15 mg kg biomass-1 day-1 for 10 successive days. In this study, healthy Oreochromis niloticus were fed with 0-10 times the therapeutic dose of 15 mg kg biomass-1 day-1 for 10 days and tracked for 43 days post dosing. Assessments of residue accrual and depletion, oxidative stress, serum biochemistry, histopathology and extent of kidney and liver damages were made. FFC dosing reduced the feed intake significantly. The therapeutic dose produced no mortalities on day 10. Dose-dependent alterations in serum biochemistry were noted upon dosing. Several histopathological alterations were observed in the kidney and liver, which vindicated the toxic potentials of FFC. The residual FFC and florfenicol amine (FFA) accrual, depletion and oxidative stress responses, such as increased malondialdehyde, total nitric oxide, ferric reducing antioxidant power and reduced glutathione S-transferase activity, were documented. The dietary FFC persuaded the physiological state of O. niloticus, the effects of which normalized sparsely with time upon cessation of dosing at the higher doses. The study provided a brief outlook on the physiological responses upon oral FFC administration, which should be kept in mind during its application for fish health safety purposes.

Modifying textural and functional characteristics of fish (Nemipterus japonicus) mince using high pressure technology.

Effect of high pressure in inducing textural and functional modification has been investigated in pink perch (Nemipterus japonicus) mince. Fish mince undergone pressurization at 200, 400 and 600 MPa for a holding period of 10 min and was compared against cooked mince (90 °C; 40 min). The treated mince at 400 and 600 MPa lost its natural viscosity and behaved like cooked mince through denaturation and formation of protein aggregates. Textural characterisation showed the retention of tenderness in 200 MPa treated samples, but become harder on application of higher pressures. Unlike heat gels, pressure induced gels were more smooth, white and elastic in nature. A decreased in reactive SH groups was observed in 400 and 600 MPa treated samples due to the formation of disulfide bonds. Hydrophobic concentration was higher in cooked and 600 MPa treatments whereas Ca2+-ATPase activity decreased after pressurization. On application of different pressures microbial reduction of 2-3 log cycles was achieved in the mince samples. Hence pressure treatments at lower ranges cannot alter the texture and functionality of protein and the mince can undergo processing as required. Besides extending shelf life, the treatments above 400 MPa can make irreversible effect on texture quality and protein functionality which is similar to that of cooking.

Effect of pressure cooking alone and in combination with other treatments on shrimp allergic protein, tropomyosin.

Shrimp allergen, tropomyosin is a highly heat stable allergen a common causative of shrimp allergy in sensitive individuals. Effect of house hold pressure cooking on immunogenicity of shrimp allergen, topomyosin from Metapenaeus dobsoni was investigated in both shrimp extract and peeled shrimp by extending the time of pressure cooking to 5, 10 and 20 min. Soaked shrimps in salt, baking soda, papain and acetic acid along with pressure cooking was also investigated. In the case of extracts, IgE activity was significantly (p < 0.05) decreased and the tropomyosin band was absent in the immunoblott using pooled sera of shrimp sensitive individuals. While in the case of whole peeled shrimp, IgE activity was significantly (p < 0.05) increased and the tropomyosin band was retained in the immunoblott analysis which indicates the retention of allerginicity in the peeled shrimp. Although pressure cooked shrimp after soaking in acetic acid didn't show significant (p > 0.05) difference to that of without soaking, the tropomyosin band was observed to be very faint or absent in SDS PAGE and immunoblott analysis which indicated the effective reduction in allegenicity of whole peeled shrimp.

Multi-drug resistance, integron and transposon-mediated gene transfer in heterotrophic bacteria from Penaeus vannamei and its culture environment.

Multi-drug resistance (MDR) in bacteria is regarded as an emerging pollutant in different food production avenues including aquaculture. One hundred and sixty out of 2304 bacterial isolates from shrimp farm samples (n = 192) of Andhra Pradesh, India, were MDR. Based on biochemical identification and 16S rRNA sequencing, they were grouped into 35 bacterial species with the predominance of Vibrio parahaemolyticus (12.5%). The MDR isolates showed highest resistance toward oxytetracycline (89%) with more than 0.2 MAR (multiple antibiotic resistance), demonstrates a high-risk source. The most prevalent antibiotic-resistance gene (ARG) and mobile genetic element (MGE) detected were tetA (47.5%) and int1 (46.2%), respectively. In conjugation experiments, overall transfer frequency was found to be in the range of 1.1 × 10-9 to 1.8 × 10-3 with the transconjugants harbouring ARGs and MGEs. This study exposed the wide distribution of MDR bacteria in shrimp and its environment, which can further aggravate the already raised concerns of antibiotic residues in the absence of proper mitigation measures.

Antibiotic resistance of culturable heterotrophic bacteria isolated from shrimp (Penaeus vannamei) aquaculture ponds.

Shrimp aquaculture is one of the fastest growing food-producing avenues, where antibiotics usage has become an issue of great concern due to the development of antimicrobial resistance in bacteria. A total of 2304 bacterial isolates from 192 samples (sediment, water, shrimp, and source water) from Andhra Pradesh, India were screened. Antibiotic resistance of bacterial isolates was highest for oxytetracycline (23.4%) followed by erythromycin (12.7%), co-trimoxazole (10%) ciprofloxacin (9.6%), and chloramphenicol (6%), of which 11.9% isolates were multi-drug resistant. Bacterial isolates from shrimp (26.7%), water (23.9%), and sediment (19.6%) samples exhibited more resistance (p ≤ 0.05) towards oxytetracycline. Higher antibacterial resistance was observed from samples of southern Andhra Pradesh (locations L6 and L7). Gram negative bacteria were more prevalent (64%) and showed significantly (p ≤ 0.01) higher resistance. This study indicated the wider distribution of antibiotic-resistant bacteria in shrimp aquaculture ponds with potential risk to humans and the environment.

Effect of high pressure and setting condition on physico-chemical, structural and functional characteristics of transglutaminase mediated fish gels.

Application of High pressure and low temperature setting condition on microbial transglutaminase (MTGase) mediated gelation was studied against conventional cooking in pink perch mince. A high pressure of 250 MPa was given to pink perch mince samples added with and without MTGase enzyme, for a holding time of 12 min and a setting condition of 25 °C for 30 min was given prior and after the treatments. Nine random experiments (T1 to T9) were made against high pressure and cooking and analysed its textural and functional properties. Addition of MTGase and setting conditions had significant effect on the textural properties of the both samples especially in inducing the gel strength. Reduction in total and reactive sulfhydryl groups observed was due to the formation of disulfide linkages, which was found more in T6 to T9. Setting condition had significant effect on protein hydrophobicity in both pressure and heat induced gels. No significant variation in the Ca2+-ATPase enzyme activity was observed among treatments. SEM images revealed more closed and dense fibrous network in samples with enzyme (T6 to T9), due to more protein polymerisation. So MTGase enzyme along with pressure treatment enhanced the conformational stability and produce stronger networks through the formation of non sulfide bonds between proteins and setting reinforced these networks. Hence the synergistic effect of high pressure and MTGase can enhance the textural and functional properties of fish gels, when compared with the conventional cooking.

In vivo characterization of histological and immunological response of allergic protein of Metapenaeus dobsonii using an adjuvant free BALB/c mice model.

Shrimp allergy, a common form of food allergy is an adverse immunological response to shrimp proteins. BALB/c mice was sensitized by an adjuvant free oral administration of purified tropomyosin, from Metpenaeus dobsonii to characterize intestinal histological responses and immunological protein recognition pattern as it is unpractical in human subjects. Sensitized mice with higher dose of tropomyosin expressed symptoms of anaphylaxis including puffiness around eyes and snout, no activity, tremor and convulsion after challenge. The responses of high level of sera IgE, tropomyosin specific IgE and histamine in the treatment groups indicated the increased allergic reaction by ELISA. Sera IgE of sensitized mice exhibited a comparable recognition pattern to tropomyosin by immunoblotting similar to human subjects. Histological changes were comparatively highly affected in the intestinal area of duodenum in the sensitized mice. Hence BALB/c mice can be used as a suitable adjuvant free shrimp allergy model for immunotherapy tools.

Identification of allergic proteins of Flower tail shrimp (Metapenaeus dobsonii).

Allergy to seafood mainly fish and shellfish has been reported. Tropomyosin is recognized as a major allergen in many crustaceans especially shrimps. A study was carried out to identify the IgE reactive proteins of allergic nature in Flower tail shrimp (Metapenaeus dobsonii), a frequently consumed shrimp in India mainly in dried form. Protein profiling and identification of IgE reactive proteins in raw and cooked extracts of Flower tail shrimp was carried out by SDS-PAGE and immunoblotting using sera of 13 patients having allergic reactions on consumption of shrimp and positive to skin prick test. The IgE binding ability was determined by ELISA and it was found higher in the case of cooked extracts ranging from 0.244 to 0.440 at 490 nm. The SDS-PAGE of raw extract revealed many protein bands between 205 and 6.5 KDa, while in the case of cooked extracts bands of 36, 20, 29 and 70 KDa were prominent. Heat resistant protein of 37 KDa, tropomyosin was showing a clear immune reaction both in the case of raw and cooked extracts was identified as the major allergen by all the patient sera. The minor proteins of raw extract identified by immune reaction are 50, 75 and 100 KDa. The identified allergen can be used for the diagnosis and management of shrimp allergy.

Rapid detection of Salmonella contamination in seafoods using multiplex PCR.

Effective monitoring of Salmonella contamination in seafood processing to conform the requirements of HACCP is a great challenge today. Such challenges can be effectively addressed, if the conventional detection methods are replaced with DNA-based molecular methods. Accordingly, it was aimed to develop a robust PCR protocol for specific detection of Salmonella spp. Out of the different primers screened, one pair of primers developed in this study targeting invA gene demonstrated 100% inclusivity for a wide range of Salmonella serotypes and 100% exclusivity for wide range of non-target species. The in silico analysis of the nucleotide sequence obtained from the PCR product suggests its potential as a hybridization probe for genus specific detection of Salmonella spp. contamination. The PCR protocol was sensitive enough to detect 15 cells per reaction using crude DNA prepared within a short time directly from artificially contaminated shrimp tissue. The study demonstrated that the result of PCR reaction can come out on the same day of sample arrival. Incorporation of this pair of primers in a multiplex PCR designed for simultaneous detection of four common seafood-borne human pathogens yielded 147 bp, 302 bp, 403 bp, and 450 bp distinct DNA bands specifically targeting E. coli, toxigenic Vibrio cholerae, Salmonella spp., and V. parahaemolyticus, respectively in a single PCR tube. The PCR methods developed in this study has the potential to be used in the seafood processing plants for effective monitoring of CCPs required for implementation of HACCP-based quality assurance system.

Polylactic acid/chitosan films for packaging of Indian white prawn (Fenneropenaeus indicus).

Composite films were developed by embedding nanochitosan (0.5%, 1% and 2%) in a polylactic acid (PLA) matrix using polyethylene glycol as a cross linking agent and polyvinyl alcohol as plasticizer. The mixture was casted into films via solvent casting. The interaction between the polylactic acid/nanochitosan (PLA/NCS) and polyethylene glycol had a significant effect on the tensile strength and the heat sealing properties. Antimicrobial properties of PLA/NCS films have been confirmed against aerobic microorganisms. PLA/NCS solvent casted films were used to pack prawn meat (Fenneropeneaus indicus) which was further stored in chilled condition for 18 days. The study proved that microbial and biochemical quality indices of prawn samples packed in different PLA/NCS film were retained and concluded that PLA/NCS composite films can be used for packing of fresh prawn to increase its shelf life.

Studies on chemical composition of yellowfin tuna (Thunnus albacares, Bonnaterre, 1788) eye.

Chemical composition viz., fatty acids, amino acids and minerals of yellowfin tuna (Thunnus albacares) eye were analyzed for better utilization of fish processing discards. Analysis of fatty acids composition by gas chromatography-mass spectrometry revealed the presence of polyunsaturated fatty acids namely docosahexaenoic acid, eicosapentaenoic acid, arachidonic acid and linoleic acid at the levels of 37.8, 7.1, 3.6 and 1.4%, respectively. The major available monounsaturated fatty acids, palmitoleic acid and oleic acid were present at the level of 17.9 and 18.3% respectively. Myristic acid was the dominant saturated fatty acid and occupied 2% of the total fatty acids. Amino acid analysis by high-performance liquid chromatography showed that the tuna eye has a high concentration of glycine (19.24 mg/100 g) followed by glutamic acid (16 mg/100 g) and aspartic acid (12.76 mg/100 g). Analysis of mineral content of tuna eye showed the presence of higher sodium and lower copper content. The results revealed that yellowfin tuna eye could be used as a potential source of ω-3 fatty acids and essential amino acids.

Characterisation of hydrolysates prepared from engraved catfish (Nemapteryx caelata) roe by serial hydrolysis.

Protein hydrolysates were prepared from defatted engraved catfish roe using alcalase enzyme by a two-stage serial hydrolysis process. The soluble hydrolysate formed after first stage of hydrolysis was removed (RH-1) and fresh enzyme was added at the same concentration to achieve further hydrolysis (RH-2). Further, compositional, surface-active and antioxidant properties of both hydrolysates were compared. The SDS-PAGE profile showed two distinct bands for RH-1, whereas no bands were visible for RH-2. On the other hand, gel filtration chromatography of the hydrolysates indicated 3-4 distinct fractions. Both the hydrolysates showed similar foam forming abilities, however, RH-1 exhibited poor foam stability. Emulsion properties of RH-1 were superior to that of RH-2. The major fractions eluted through gel filtration column were screened for antioxidant properties. Higher DPPH radical scavenging and metal chelating properties were observed for RH-1 second fragment, whereas FRAP and Fe(2+) reducing power was highest for second fragment of RH-2.

Assessment of polyaromatic hydrocarbons and pesticide residues in domestic and imported pangasius (Pangasianodon hypophthalmus) fish in India.

BACKGROUND: The pangasius catfish (Pangasianodon hypophthalmus) is a ubiquitous item of seafood in global markets. However, pesticide residues in aquaculture fish, arising from agricultural run-off and/or direct application during pond preparation, pest control and harvest, are a potential food safety concern. This study assessed the level of chemical hazard in domestic and imported pangasius fish in India. RESULTS: A total of 119 contaminants, including polyaromatic hydrocarbons (PAHs), organochlorines (OCs) and other groups of pesticides, were screened in 148 samples during 2014-2015 as the first endeavour of its kind in an Indian context, employing a validated gas chromatography/tandem mass spectrometry (GC/MS/MS) method. Apart from the low-level incidence of OCs, pesticides such as quinalphos, malathion, parathion-methyl, etc. were detected in 38% of the samples. In comparison with Indian pangasius, fewer contaminants at low residue level were detected in pangasius fillets imported from Vietnam. CONCLUSION: The human dietary exposures of the residue concentrations detected were less than the maximum permissible intakes and hence appeared safe. However, detection of commonly used pesticides indicated their direct application in aquaculture and contamination from agricultural run-off. This emphasizes the need for continual residue monitoring in aquaculture fish. © 2015 Society of Chemical Industry.