Seafood Research Articles

Maritime Potential Optimization in the Riau Islands Province

The archipelagic province’s maritime development has thus far been disproportionately attributed to fisheries and primary marine activities, restricting the evaluation of the ideal maritime sector optimization within the economy. The maritime notion and its scope apply to activities in more diverse fields. It accords with experts' conceptual and theoretical definitions and the Indonesian legal perspective as well). This study aims to assess the extent to which maritime performance optimization has occurred throughout the Riau Islands Province based on seventeen activities. Using a well-known quantitative technique, i.e., Location Quotient, Shift-Share, Overlay, and Klassen's Typology, we found that maritime optimization performed differently in each district and municipality of the Riau Islands Province. Based on the results, Batam is the region with the best maritime sector performance, followed by Bintan, Tanjungpinang, Karimun, and Lingga. Meanwhile, Anambas and Natuna are relatively lagging. In addition, the study results show that the optimization of the maritime sector is not limited to the creation of added value in primary outputs such as fisheries, mining, and quarrying. It also considers secondary and tertiary maritime activities such as manufacturing, trade, and services such as sea transportation, accommodation, food, and beverages, where there are many marine tourism activities. In addition, the results suggest that maritime sector optimization is not restricted to creating added value in the primary output but also secondary and tertiary.

A study on the effects of interfering with the conventional sequential protocol for chemical isolation and characterization of chitosan from biowaste of giant freshwater prawn Macrobrachium rosenbergii

Unless better measures are put in place to address the environmental and social impacts emanating from the huge waste generated from sea food processing industries; ‘tragedy of the commons’ is inevitable. Needless to re-emphasise the enormous contributions of aquaculture as the perfect substitute to capture fisheries which has been proven unsustainable. Be that as it may, the huge amount of bio-waste produced could be transformed into useful products such as chitin and chitosan with far reaching applications. Chitin and chitosan have been consistently processed from many sources following the traditional chemical sequence of Demineralization (DM), Deproteinization (DP), Decolouration (DC) and Deacetylation (DA). In this study, this method was re-ordered, resulting to 4 sequences of chemical processes. HCl, NaOH, ethanol (97%) and NaOH (50%) were used for DM, DP, DC and DA respectively. The results of this study showed that better chitin (23.99 ± 0.61%) and chitosan (15.17 ± 1.69%) yields were obtained from sequence four (SQ4) following the order of DC-DM-DP-DA. In addition, physicochemical properties such as DDA (80.67 ± 2.52%) and solubility (66.43 ± 2.61%) were significantly higher (p ≤ 0.05) in SQ4 thereby making the obtained product suitable for use as coagulant and flocculant in wastewater treatment. Results of FTIR, XRD and SEM of the study proved that the resultant product exhibited the characteristic nature of chitosan with porous and fibril nature. In the analysis of the physical properties of chitosan obtained from bio-waste of Macrobrachiumrosenbergii, the high Carr's index (CI) and low bulk as well as tapped densities were an indication that the chitosan produced in this study had poor flowability and compressibility, thereby making it unfit for application in pharmaceutical industries.

Identifying urban consumer behaviour in purchasing of frozen meat and meat products in Andhra Pradesh

The frozen food products, especially frozen meat products, offer enhanced palatability as compared to their homecooked counterparts, these products are available year-round regardless of the season. A representative sample of 120 meat consumersin three cities of Andhra Pradesh i.e., Vishakhapatnam, Vijayawada and Tirupati were taken for the study. Consumption pattern of majority of respondents reveals that they consume eggs daily, poultry meat once a week, mutton and sea food once in a month and never consumed beef and pork. Average monthly consumption of majority respondents reveals they consume 60-120 eggs, 3-5 kg chicken, upto 1 kg mutton and sea food, respectively.The major reasons for consumer stimuli towards purchasing of meat and meat products were meat is rich source of protein, tasty and easily available. The most considered motives by sample respondents for purchasing and consumption of meat and meat products were ‘Meat is good for healthy lifestyle’ and ‘Consumption of meat is in family/religion culture’, respectively. The major motives for frozen meat and meat products consumption were “Convenience of store and use”, “Pre prepared (readiness)” and “Time saving”, respectively. The majority of the respondents prefer 30-40 per cent frozen fish and sea food in their diet when compared to other categories of meat.

Assessment of endocrine disrupting chemicals in breast milk: Association with dietary habits and duration of lactation

The present study was aimed to assess infant safety associated with the presence of persistent organochlorine pesticides (OCPs) in breast milk, a possible route of transfer of endocrine–disrupting chemicals to newborns in North India. Colostrum and breast milk samples (n = 130) were collected at different stages of lactation. Pesticides analysis was performed using gas chromatography mass spectrometry (GC–MS). We observed that of all the samples analysed, OCPs concentration was higher in breast milk than in colostrum, suggesting pesticides contamination increases over lactation period. As far as OCPs are concerned, dieldrin [1196.64 ± 673.75 ng/g lipid weight (lw)], and β-HCH [1107.78 ± 1301.72 ng/g lw], were the predominant OCPs, followed by aldrin [977.09 ± 707.69 ng/g lw], α-HCH [948.04 ± 476.65 ng/g lw] and 1,1′-(2,2-Dichloroethene-1,1-diyl)bis(4-chlorobenzene) (p,p’DDE) [790.11 ± 399.35 ng/g lw]. The association between OCPs levels and women dietary habits were also explored, and all the OCPs were grouped and compared to each other by consumption level of fish, meat, sea foods, eggs, and dairy products. We found that women consuming non vegetarian food, like fish and meat, were exposed 3.5 times more to OCPs than women consuming vegetarian food. In addition, we also observed that factors like mother's age was positively (<0.005 - <0.001) correlated while gestational age and infant birth weight were negatively (<0.005) associated with the levels of OCPs in colostrum and breast milk, respectively. Unfortunately, neither any standards nor guidelines are available for the use of pesticides, therefore, it is suggested that careless use of OCPs should be checked and suitable remedial measures be taken to decrease human contamination. Moreover, further studies are warranted to elucidate relationship between pesticide residues in breast milk and the maternal and child health.

Antibiogram, Genomic and Phylogeny of Stool and Seafood Isolates from Some Cholera-Prone Coastal Communities in Rivers State, Nigeria

Cholera is a significant public health threat across the globe, especially in coastal regions with poor water supply. This study was carried out to determine the antibiogram, genomic, and phylogeny of stool and seafood isolates from some cholera-prone coastal communities in Rivers State, Nigeria. A total of 400 stool samples and 42 different seafood were aseptically collected and examined using standard microbiology and molecular techniques. An antibiogram of isolates from seafood and stool samples was assayed. Genes for virulence, resistance, and relatedness of bacteria identified were also determined. The isolates from the stool and seafood were examined for susceptibility to some selected antibiotics. The findings showed the prevalence rate of cholera in the communities as follows: 16% in Kaa, 30% in Andoni, 4% in Ogu/Bolo, and 10% in Abua/Odual. The isolates from stool were susceptible to Ciprofloxacin and Gentamycin with a susceptibility rate of 94.12% each while 100% resistance was recorded against Amoxicillin-clavulanic acid, 94.12% against Amikacin and 88.24% against Colistin. For the sea foods, the isolates were susceptible to gentamycin and ciprofloxacin with a susceptibility rate of 91.43% and 82.86% respectively. Resistance was also recorded against Colistin (88.57%) and Azithromycin (82.86%). Testing the isolates for the presence of 16SrRNA genes showed that all were positive with 1500 bp 16SrRNA gene band size. TEM, OXA, SHV, and CTX-M resistant genes were detected whereas the virulence genes were TDH and AcrB. The phylogenetic analysis revealed isolates from seafood to be Aeromonas dhakensis, Vibrio parahaemolyticus, Vibrio azureus, and Providencia rettgeri, while in stool samples they were Enterobacter sichuanensis, Enterobacter hormaechei, Providencia sneebia, and Proteus vulgaris. Providencia stuartii, Proteus mirabilis, Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae were common isolates from both seafood and stool samples. This study has shown that not all reported cases of cholera are caused by Vibrio cholerae. Therefore, attention should be paid to other water-borne bacteria in every outbreak, especially in coastal communities.

The twelve fundamental dimensions of a high quality Indo-Mediterranean diet

High-quality Indo-Mediterranean foods are characterised with unrefined, unprocessed foods, whole grains such as dry millets and beans and porridge. Vegetables such as leaves and gourds, nuts and fruits such as apples, grapes, papaya, guava, etc are major components of this diet. It seems that healthy vegetable oils such as olive, mustard, rape seed oil and protein sources that are beneficial; beans, pulses, cottage cheese are crucial in this diet. Among animal sources, white meats; such as sea foods should also be part of this diet. Vegetables and spices with medicinal properties; gourds, turmeric, fenugreek, coriander and cumin may also be called high quality nutraceutical foods, respectively. There is a need to find out traditional foods from all other countries which may be protective and healthy. There is evidence that calories have tremendous role in weight gain and weight loss. It seems that emphasis on food quality is crucial for prevention of oxidative stress and inflammation in the adipocytes, which predispose obesity and risk of cardiovascular diseases (CVDs) and diabetes. There are gaps in knowledge about the qualities of traditional foods, which prompt authors to present this communication.

Prevalence of Salmonella in Sea Foods and Its Resistance to Drugs

Salmonella are non-spore forming, predominantly motile enterobacteria with peritrichous flagella (all around the cell body). They are intracellular pathogens causing illness. They usually invade only the gastrointestinal tract and cause Salmonellosis. Humans become infected most frequently through contaminated food or water. Sea foods are mostly associated with Salmonella infections. This study therefore was carried out to isolate Salmonella and determine the antibiotic sensitivity patterns of the Salmonella isolates from sea foods associated with food-borne diseases. These sea foods were obtained from three different selected markets within Port Harcourt Metropolis, Rivers State. A total of three (3) sea food samples were collected at random from each of the market. The samples were put through standard microbiological techniques. The result of total heterotrophic bacterial counts showed that Prawn from Mile 1 market had high count of 2.06x108 cfu/g while Crab from Creek Road market had the least count of 1.15x108 cfu/g. The result of total coliform count showed that Crab from Mile 1 market had the highest count of 2.86x106 cfu/g while Periwinkle from Creek Road market had the least count of 2.30x106 cfu/g. Also, the result of salmonella shigella count showed that Periwinkle from Mile 1 market had the least count of 0.76x105 cfu/g while Crab from Creek Road market had the highest count of 2.80x105 cfu/g. Characteristics of bacterial isolates from the sea foods showed that Proteus sp., Bacillus spp., Pseudomonas sp., Micrococcus sp., Staphylococcus aureus, Escherichia coli, and Salmonella spp. were present and identified from the samples. The result of the antibiotic susceptibility pattern of the Salmonella isolates showed that all the isolates were 100% susceptible to Tarivid, Peflacine, Septrine and Ciprofloxacin while they exhibited 100% intermediate sensitivity or resistance to the other antibiotics such as Ceporex, Nalidixic acid, Ampicillin, Gentamycin, Streptomycin, and Augmentin. The result of the multidrug resistance index of 3 (100%) of the 3 Salmonella isolates had a MAR index ≥ 0.2. The presence of these organisms in sea food could pose threat of food-borne infection as well as resistance to some commonly used antibiotics. Enforcement of existing laws associated with food storage, preparation and hygiene should be done in order to prevent or reduce these food-borne diseases such as salmonellosis.

ANALYSIS OF ANTIFUNGAL ACTIVITY USING POWDERED CUTTLEBONE Sepia pharaonis EHRENBERG, 1831 AGAINST SELECTED PATHOGENS

Sea food is regarded as a good source of animal protein since it had a high content of polyunsaturated fatty acids. Cephalopods are considerably important a food resource as well as in scientific investigations. The aim of the present study is to evaluate the antifungal activity of methanolic extract of powdered cuttlebone of Sepia pharaonis against five fungal strains such as, Candida albicans, Aspergillus flavus, Mucor, Aspergillus niger and Aspergillus fumigates using well diffusion method. The methanolic extract was active against Candida albicans, Mucor and Aspergillus fumigates at higher concentarion level and dormant against Aspergillus flavus and Aspergillus niger. These results revealed that the methanolic extract of powdered cuttle bone possess relatively good antifungal activity.

Penerapan Free Ongkir System pada Pemasaran Seafood Melalui Facebook

Advances in technology also have an impact on business actors, especially traders. Cultural changes in marketing strategies must be carried out by utilizing digital. AB sea food as a business actor that provides marine products has also revolutionized its marketing strategy. This is done to maintain the continuity of its business so as not to lose competitiveness. This study aims to determine the application of the free shipping system in seafood marketing strategies through Facebook. This research uses descriptive qualitative method. Data obtained from three aspects, namely observation, interviews and documentation. The results obtained from this study indicate that the application of the free shipping system in the marketing strategy through Facebook is increasing the attractiveness of consumers in choosing AB sea food products, the more consumers and resellers asking to partner, so the result is an increase in income.

Quantitative Sensing of Domoic Acid from Shellfish Using Biological Photonic Crystal Enhanced SERS Substrates.

Frequent monitoring of sea food, especially shellfish samples, for the presence of biotoxins serves not only as a valuable strategy to mitigate adulteration associated health risks, but could also be used to develop predictive models to understand algal explosion and toxin trends. Periodic toxin assessment is often restricted due to poor sensitivity, multifarious cleaning/extraction protocols and high operational costs of conventional detection methods. Through this work, a simplistic approach to quantitatively assess the presence of a representative marine neurotoxin, Domoic acid (DA), from spiked water and crab meat samples is presented. DA sensing was performed based on surface-enhanced Raman scattering (SERS) using silver nanoparticle enriched diatomaceous earth—a biological photonic crystal material in nature. Distinctive optical features of the quasi-ordered pore patterns in diatom skeleton with sporadic yet uniform functionalization of silver nanoparticles act as excellent SERS substrates with improved DA signals. Different concentrations of DA were tested on the substrates with the lowest detectable concentration being 1 ppm that falls well below the regulatory DA levels in seafood (>20 ppm). All the measurements were rapid and were performed within a measurement time of 1 min. Utilizing the measurement results, a standard calibration curve between SERS signal intensity and DA concentration was developed. The calibration curve was later utilized to predict the DA concentration from spiked Dungeness crab meat samples. SERS based quantitative assessment was further complemented with principal component analysis and partial least square regression studies. The tested methodology aims to bring forth a sensitive yet simple, economical and an extraction free routine to assess biotoxin presence in sea food samples onsite.

Vitamin and Mineral Contents in Shrimps, Oysters and Periwinkles Harvested from Brass Local Government Area in Bayelsa State, Nigeria

Sea foods have been a very good source of nutrients to man. In this research, the nutritional value of three sea foods namely shrimps, oysters and periwinkles obtained from Brass Local Government Area, Bayelsa State were investigated. Vitamins were analyzed with HPLC, while the minerals were determined using AAS. From the findings, phosphorus is the most concentrated mineral in the three seafood studied, with significantly (p≥0.05) higher concentrations of 3112.860ppm±15.204, 2117.863ppm±22.625 and 2906.524ppm±31.850 in shrimp, oyster and periwinkle respectively. The least concentrated minerals were iron and zinc with values of 0.031ppm±0.000 and 0.043ppm±0.001 for Shrimp, 0.056ppm±0.002 and 0.112ppm±0.021 for oyster and 0.056ppm±0.005 and 0.026ppm±0.000 for periwinkle respectively. Despite the fact that oil exploitation activities in Bayelsa state results in pollution, Shrimps, oysters and periwinkles from the study still can still serve as sources of vitamins and minerals, hence, the findings of this study can be applied to future research on human nutrition.

Screening of chitin degrading bacteria from the gut of Asian common toad Duttaphrynus melanostictus: Implication for valorization of chitin rich seafood waste

Chitin is a structural component of many invertebrates and the second most abundant biopolymer after cellulose. Owing to its high insolubility, waste management of chitin rich seafood has severe environmental consequences. Despite the value added bioconversion of waste chitin into commodity products like reducing sugars, its biodegradation by bacteria is still lacking. To this end, we have isolated and characterized chitin degrading bacteria from the gut of common Asian toad, Duttaphrynus melanostictus . The isolates, FG4 and ND3 demonstrated highest chitin degradation activities of 1.44 ± 0.129 U/mL and 1.269 ± 0.138 U/mL respectively. Molecular phylogeny using 16S rRNA gene sequence affiliated FG4 to Stenotrophomonas maltophila and ND3 to Bacillus paramycoides , respectively. Among the tested substrates, highest chitinase activities of 4.210 ± 0.070 U/mL and 1.724 ± 0.494 U/mL were exhibited by S. maltophila FG4 on prawn shells (PS) and chitin flakes (CF), respectively. Similarly, the highest substrate degradation ratio of prawn shells and chitin flakes were 49.52% and 38.15% by S. maltophila FG4. Furthermore, scanning electron microscopy revealed adhesion of bacteria and creation of pores on the substrates. The Fourier transform infrared spectroscopy (FTIR) and X - ray diffraction analysis revealed hydrolysis of prawn shells and chitin flakes by bacteria. Further, the high-resolution mass spectrometric (HRMS) analysis confirmed production of N-acetyl D glucosamine by S. maltophila FG4 on prawn shells. Thus, the present study identifies D. melanostictus gut as a unique reservoir to isolate chitinolytic bacteria that may have potential industrial and therapeutic applications. • First report of bioprospection of amphibian guts for bacteria capable of chitin hydrolysis. • Gut chitinolytic isolates could utilize sea food wastes as sole carbon source. • Applications in production of valuable byproducts such as N-acetyl-D-glucosamine.

Improved surface-enhanced Raman scattering performance enabled by hydrophilic-hydrophobic piezoelectric PVDF-silver substrate

It holds extreme significance in expansive fields to promote the sensitivity and quantitative aptitudes of surface-enhanced Raman scattering (SERS) substrate. Herein, a distinctive piezoelectric polyvinylidene fluoride (PVDF) film combined with hydrophilic-hydrophobic strategy was ventured into SERS technique to facilitate a superior self-energized hybrid substrate. Notably, enhanced localized electromagnetic field of Ag nanoparticles (Ag NPs) could be rationally induced by pressing or bending the PVDF film, enabling a tunable ultra-high sensitivity. The quantitative level of the sensitive detection was further improved by employing a facile hydrophilic-hydrophobic strategy to uniformly anchor and enrich analytes, ascertaining a low variation of 11.8%. As a proof-of-concept, an in-situ collection and assay of enrofloxacin residue on fishes with different surface roughness were successfully accomplished by the pressed substrate and trustworthy recovery rates were demonstrated. Briefly, the hydrophilic-hydrophobic self-energized PVDF-Ag hybrids demonstrated superior SERS enhancement with a promising uniformity, providing a novel and practical design options for sensing devices and facilitating the noninvasive monitoring of residue in sea food. • A novel kind of self-energized E-SERS substrate with a tunable ultra-high sensitivity was developed. • An facile hydrophilic-hydrophobic strategy was used to improve the accuracy of the E-SERS signal. • A practical monitoring of enrofloxacin residue on fishes was achieved by the self-energized substrate.

Prevalence of Thyroid Problems Among Patients Attending at Siddharthanagar City Hospital

Thyroid gland is vital gland. It produces Thyroxine T3 and Tri-Idothyronine T4 hormones which are needed for the growth and development. Iodine is needed for the formation of T3 and T4 hormones. Iodine is found in different food such as sea food, vegetables produced in Iodine rich soil and table salt. The associated problems of thyroid gland are hypothyroidism and hyperthyroidism. The objective of this study was to find out the prevalence of thyroid problems attending at Siddharthanagar City Hospital.&#x0D; It was hospital based retrospective study. Data related to thyroid problems T3,T4 and TSH was collected from hospital laboratory reports . The tests were done using Semi Auto Clia Plate Analyzer of TOSOH India Company.&#x0D; The total number of lab reports was 299 taken for study. Among them the percentage of male and female was 21.7 and 78.3 respectively. The overall prevalence of thyroid problems was 5.9% among general public. The overall prevalence of hypothyroidism was 9.69% and hyperthyroidism was 2.17% respectively. The prevalence of thyroid problems was seen more in female.&#x0D; This study showed that thyroid problem including hyperthyroidism and hypothyroidism is common. Female population and 21-40 years age group are highly suffered in comparison to male population.

The Characteristics of Cracker Fish and Beef Products Processed Under Sudanese Condition

Purpose: The study was designed to evaluate the processing of fish and beef crackers under Sudanese conditions.&#x0D; Methodology: 2kg Tetraodon fahaka fish meat, 2kg beef top side cut, corn flour, and spices were purchased from local market, and then prepared for processed cracker. The processing formula consist of 50% Meat or fish with 50% corn flour.&#x0D; Findings: The products were significantly different chemically in lipid content 19% for fish and 14 % for beef cracker and similar in moisture, protein, and ash%. (WAI) water absorption index, (WSI) water Solubility index determined without different between products. Linear expansion and oil absorption were differently 15.6, 10.7, 19.7, and 2.1for fish and beef cracker respectively. Sensory characteristics were determined included colour, falavor, Crispness, overall acceptability. The panelists prefer cracker fish in overall acceptability.&#x0D; Unique contribution to theory, practice and policy: Cracker fish products are traditional food in Asia; it’s made of fish and sea food which increases the nutritional value, and is taken between meals. Most of the snacks available in the market are mainly based on cereals, which are high in calorie and low in protein content. For this reason, snacks like fish or beef crackers with high protein content was thought to be developed for nutritional enrichment. Cracker fish and beef were processed in Sudan had acceptable chance to increases the nutritional value for children which like crispness. Cracker it can be useful in IDP camp for displaced human in Darfur province.

Systematic Surveillance and Meta-Analysis of Antimicrobial Resistance and Food Sources from China and the USA.

Since the discovery of antibiotics in the 20th century, they have been used to fight against infections. The overuse of antibiotics in the wider environment has resulted in the emergence of multidrug-resistant bacteria. In developing countries such as China and developed countries such as the USA, there is evidence of the high pervasiveness of antibiotic-resistant infections. However, the studies on the spread of antibiotic-resistant microorganisms that inform about the consequences are limited. The aim of our study was to analyze and compare antimicrobial resistance (AMR) identified in published research papers from that found in different food sources, which were published between 2012 and December 2021, covering most retail food items. Out of 132 research papers identified, 26 papers have met our strict criteria and are included in the qualitative and quantitative analysis. The selected papers led to 13,018 food samples, out of which 5000 samples were contaminated, including 2276 and 2724 samples from China and the USA, respectively. Meat, aquatic products, milk, and eggs show high to medium potential for AMR exposure to Gram-positive bacteria such as Staphylococcus, Enterococci, etc. and Gram-negative foodborne pathogens such as Campylobacter, Salmonella, Vibrio, etc. Most of the food samples show antibiotic resistance to β-lactams, tetracycline, quinolones, and aminoglycosides. Retail food products such as meat, sea food, and some other food products, as well as AMR genetics and technically important bacteria, are proposed to be better merged with mitigation strategies and systematic One Health AMR surveillance to minimize the knowledge gaps and facilitate comprehensive AMR risk computation for the consumers.

Health risk assessment to polychlorinated naphthalenes dioxin-like compounds in French sea food consumers

There has been a recent revival of interest in some historical contaminants such as polychlorinated naphthalenes (PCNs). However, occurrence data are still lacking in some countries although industrial production of PCNs has been reported. This observation led to the first ever assessment of their presence in fish and seafood products in France in the present work. Their analysis was integrated in an already validated method applied for polychlorinated dibenzodioxins/furans (PCDD/Fs) and polychlorinated biphenyls (PCBs), based on the structural similarity existing between these POPs.Performances of the method (LODs in the range 0.10–0.28 pg g−1 wet weight (ww), LOQs in the range 0.33–0.93 pg g−1 ww), enabled monitoring 69 di-to octachlorinated congeners in a large representative set of fish and seafood samples collected in 2005 in four coastal areas of the French mainland (n > 30). Their systematic presence was demonstrated in all the investigated seafood products, with levels (ΣPCNs in the range 2–440 pg g−1 wet weight) close to those already reported in other European fish and seafood sampled at a similar period. In addition, the robust measurement of almost all possible PCNs (69/75) allowed a fine interpretation of the observed profiles, highlighting in particular the specificities between species and fishing areas. Compared to the PCDD/Fs, PCBs, and polybrominated diphenylethers levels also measured for this set of samples, PCNs were observed as minor contributors to total concentrations (0.05–3.2%). The specific PCN related dietary dioxin-like exposure could be evaluated at 0.028–0.051 pg of toxic equivalent (TEQ) per kg of body weight per week for an adult, based on fish and seafood consumption only. Overall, this study provides the first baseline data on the occurrence of a large number of PCNs in France, which will allow future evaluation of temporal trends and associated risks.

Strategic Flexibility, Institutional Pressure, and Proenvironmental Behavior among Sea Food Enterprises: Mediating Effect Based on Paradoxical Cognition

The proenvironmental behavior of Sea Foods Enterprises is the microfoundation for the transformation and upgrading of the traditional marine aquatic industry. Integrating institutional theory and strategic cognitive theory, we use 221 marine aquaculture companies as research samples to explore the driving effect of strategic flexibility (resource flexibility and coordination flexibility) and institutional pressure (regulatory pressure and normative pressure) on proenvironmental behavior, and the mediating role of paradoxical cognition. The conclusion is as follows: (1) strategic flexibility and institutional pressure jointly drive Sea Food Enterprises to adopt proenvironmental behaviors, of which regulatory pressure has the most significant impact. (2) Paradox cognition plays a partial mediating role in the interaction between resource flexibility, coordination flexibility, regulatory pressure, and proenvironmental behavior. There is no mediating effect in the interaction between normative pressure and proenvironmental behavior.

Aptamers-functionalized nanoscale MOFs for saxitoxin and tetrodotoxin sensing in sea foods through FRET

Saxitoxin (STX) and tetrodotoxin (TTX) are widely distributed and extremely harmful marine toxins, it is certainly worth to spend effort to develop facile methods to detect them in sea food for human safety. In this work, two nano-sensors were developed by combining with two zirconium fluorescence Nanoscale metal–organic frameworks (NMOFs) with two emissions and TAMRA-labelled aptamers for STX and TTX sensing, respectively. The recognition of STX and TTX by these nano-sensors could change the structure of aptamer, which caused the blue or green emissions from NMOFs (energy donor) decreased while red emission from TAMRA-labelled aptamers (energy acceptor) increased owing to fluorescence resonance energy transfer (FRET) effect. Based on this strategy, NMOFs-Aptasensor 1 and NMOFs-Aptasensor 2 were developed for the ratiometric detection, with detection limits of 1.17 nM and 3.07 nM for STX and TTX, respectively. Moreover, NMOFs-Aptasensors displayed significant stability, pH-independence, selectivity and NMOFs-Aptasensors were successfully applied in shellfish sample for toxin sensing.

Comprehensive non-target screening of biomagnifying organic contaminants in the Baltic Sea food web

High-resolution mass spectrometry (HRMS) based non-target screening (NTS) is a powerful approach for the simultaneous determination of multiple environmental contaminant classes in complex biota samples. In this study, trophic biomagnification factor (TMF) directed NTS was performed to find and (tentatively) identify known, emerging, and new chemical contaminants that are persistent and biomagnify in Baltic Sea biota. The investigated food web included seven species: one filter feeder (blue mussel, Mytilus edulis), two fish (eelpout, Zoarces viviparous; herring, Clupea harengus), two marine mammals (harbor porpoise, Phocoena phocoena; grey seal, Halichoerus grypus) and two birds (guillemot, Uria aalge; white-tailed sea eagle, Haliaeetus albicilla). The NTS procedure included extraction with organic solvent mixtures, two-step high-resolution gel permeation chromatography clean-up, Florisil® fractionation, gas chromatography (GC) HRMS analysis in electron ionization (EI) and electron capture negative ion chemical ionization (ECNI) modes, and NTS data processing. The latter was performed differently for the EI and ECNI data: the EI data were treated using a flexible and highly automated TMF-directed NTS workflow, whereas the ECNI data were treated with a simpler and less automated workflow that specifically screened for brominated compounds. The two workflows collectively revealed biomagnification (statistically significant TMF values) of >250 tentatively identified compounds, including legacy persistent organic pollutants (POPs), such as PCBs and PCB-related compounds, DDT and its metabolites, and organochlorine pesticides (OCPs), contaminants of emerging concern (CECs), and halogenated natural products (HNPs). Among the tentatively identified CECs, nine have not previously been reported in environmental biota samples. These included four polymer additives (used as antioxidants, rubber additives or plasticizers) and two cosmetic product additives (ethyl myristate and isopropyl palmitate). The CECs should be prioritized for future structure verification and quantification using reference standards.