Evaluation of whey protein coating containing nanoliposome dill (Anethum graveolens L.) essential oil on microbial, physicochemical and sensory changes of rainbow trout fish

The aim of this study was to investigate the effect of whey coating containing dill (Anethum graveolens L.) essential oil nanoliposome on the physicochemical, microbiological and sensory characteristics of rainbow trout (Oncorhynchus mykiss). Treatments comprise: sample without coating (control), coating containing whey, coating containing whey with essential oil (whey-EO) and coating containing whey with nano EO (whey-NEO). The particle size, zeta potential, polydispersity index and the encapsulation efficiency were ranged from 142 to 159 nm, -16.3 to -11.7 mV, 0.79 to 0.88 Mw/Mn and 45.85-70.01 %, respectively. Microbial analysis, after 21 days, the maximum and minimum of TVC (total viable counts), TPC (total psychrophilic counts) and LAB (lactic acid bacteria) counts were related to control (8.16 for TVC, 8.46 for TPC and 7.7 log CFU/g for LAB) and whey + NEO (7 for TVC, 7.3 for TPC and 6.16 log CFU/g for LAB), respectively. Also, results of pH, peroxide value (PV), thiobarbituric acid reactive substances (TBARS) and total volatile base-nitrogen (TVB-N) after 21 days were ranged from 6.3 (whey-NEO) to 7.5 (control), from 11.5(whey-NEO) to 20.9 mEq/Kg (control), from 5.23(whey-NEO) to 8.34 mg MDA/kg (control) and from 22.5 (whey-NEO) to 37 mg N/100 g (control), respectively. Finally, in all sensory evaluation items (texture, off-odor, discoloration and red color), the best result after 21 days was related to whey-NEO (score = 1). Consequently, the edible coating comprising whey and nanoliposome of EO could be effective to the maintenance of fish's microbiological, physicochemical, and sensory properties.

Elevated arsenic level in fasting serum via ingestion of fish meat increased the risk of hypertension in humans and mice

Aims

There has been a shortage of human studies to elucidate the association between serum arsenic levels and the prevalence of hypertension. This study multidirectionally investigated associations among arsenic exposure, dietary ingestion, and the risk of hypertension by combined human epidemiological and mouse experimental studies.

Methods and results

This study focused on the total arsenic level in fasting serum, a biomarker of arsenic exposure. Associations among ingestion frequencies of 54 diet items of Japanese food separated into six categories, total arsenic level in fasting serum, and the prevalence of hypertension were investigated in 2709 general people in Japan. Logistic regression analysis demonstrated a dose-dependent association between serum arsenic level and hypertension and a positive association between the ingestion of fish meat and hypertension. Further analysis showed that the latter association was fully mediated by increased fasting serum arsenic levels in humans. Similarly, oral exposure to the putative human-equivalent dose of arsenic species mixture with the same ratios in a common fish meat in Japan increased systolic blood pressure and arsenic levels in fasting serum in mice.

Conclusion

This interdisciplinary approach suggests that fish-meat ingestion is a potential risk factor for arsenic-mediated hypertension. Because the increased consumption of fish meat is a recent global trend, health risks of the increased ingestion of arsenic via fish meat should be further investigated.

Health effects and risks associated with the occurrence of pharmaceuticals and their metabolites in marine organisms and seafood

Pharmaceuticals and their metabolites are continuously invading the marine environment due to their input from the land such as their disposal into the drains and sewers which is mostly followed by their transfer into wastewater treatment plants (WWTPs). Their incomplete removal in WWTPs introduces pharmaceuticals into oceans and surface water. To date, various pharmaceuticals and their metabolites have been detected in marine environment. Their occurrence in marine organisms raises concerns regarding toxic effects and development of drug resistant genes. Therefore, it is crucial to review the health effects and risks associated with the presence of pharmaceuticals and their metabolites in marine organisms and seafood. This is an important study area which is related to the availability of seafood and its quality. Hence, this study provides a critical review of the information available in literature which relates to the occurrence and toxic effects of pharmaceuticals in marine organisms and seafood. This was initiated through conducting a literature search focussing on articles investigating the occurrence and effects of pharmaceuticals and their metabolites in marine organisms and seafood. In general, most studies on the monitoring of pharmaceuticals and their metabolites in marine environment are conducted in well developed countries such as Europe while research in developing countries is still limited. Pharmaceuticals present in freshwater are mostly found in seawater and marine organisms. Furthermore, the toxicity caused by different pharmaceutical mixtures was observed to be more severe than that of individual compounds.

Online extraction based on ionic covalent organic framework for sensitive determination of trace per- and polyfluorinated alkyl substances in seafoods by UHPLC-MS/MS

The ionic covalent organic framework (TPB-BFBIm-iCOF) was facilely synthetized by the size-controllable confinement method and chosen as the online solid phase extraction (SPE) adsorbent. This adsorbent showed fast adsorption equilibrium (5 min) and high adsorption capacity (87.7-140.8 mg g^-1) for the per- and polyfluorinated alkyl substances (PFASs). The TPB-BFBIm-iCOF microsphere revealed the satisfactory enrichment performance for PFASs by means of the electrostatic interaction, hydrophobic effect and ordered channel structure. After extraction, the loaded TPB-BFBIm-iCOF-online SPE column was eluted and applied to the ultrahigh performance liquid chromatography tandem mass spectrometry analysis. Under the optimum conditions, the method displayed satisfactory linearity (R² ≥ 0.9910) and low limits of detection (≤0.0017 ng g^-1) for five seafoods. The relative recoveries of PFASs were 85.3%-109.4% with the relative standard deviation ≤ 9.9%. The method exhibited potential value in monitoring the toxicokinetics and environmental behaviors of PFASs.

Recent advances in seafood bioactive peptides and their potential for managing osteoporosis

Marine biodiversity provides a range of diverse biological resources, including seafoods that are rich in protein and a well-balanced amino acid composition. Previous studies have shown that peptides can improve bone formation and/or inhibit bone resorption, suggesting the potential for seafood bioactive peptides (SBPs) in development of food and pharmaceuticals for management of osteoporosis. In this review, we provided an up-to-date overview of the anti-osteoporosis activity of SBPs and describe their underlying molecular mechanisms. We focus on SBPs' development, broadening the scope and depth of research, as well as strengthening in vivo and clinical research. In vitro cell cultures and in vivo animal osteoporosis models have demonstrated the potential for seafood-derived SBPs, including fish, mollusks, crustaceans, seaweed and microalgae, in preventing osteoporosis. These peptides may act by activating the signaling pathways, such as BMP/Smads, MAPK, OPG/RANKL/RANK, and NF-κB, which are associated with modulation bone health.

Polycyclic aromatic hydrocarbons in sediments and marine organisms: Implications of anthropogenic effects on the coastal environment

Intensive human activities aggravate environmental pollution, particularly in the coastal environment. Sixteen priority polycyclic aromatic hydrocarbons (PAHs) were determined in the sediments and marine species from Zhanjiang Harbor, a large harbor in China. The total PAH concentrations ranged from 151 to 453 ng/g dry weight (dw) in sediments and from 86.7 to 256 ng/g wet weight (ww) in organism tissues. High levels of PAHs occurred in the sample sites next to the estuary. A decrease in PAH levels was observed in comparison to the previous survey prior to 2012. Fish exhibited lower lipid weight normalized PAH concentrations than the other species, which may be related to their efficient metabolic transformation. Three ring PAHs dominated both in marine sediments and species, but low molecular weight PAHs exhibited higher proportions in biota than in sediments (p < 0.05). Petrogenic and pyrolytic sources both contributed to the occurrence of PAHs, and the latter became increasingly important in the study area. The ecological risk from PAHs in the sediments was relatively low (9% incidence of adverse biological effect) according to the effects-based sediment quality guideline values. Exposure to PAHs via consuming seafoods might pose a health risk to local residents. Overall, these results revealed anthropogenic activities in the coastal area have an impact on the local ecosystem.

Ultra-trace determination of methylmercuy in seafood by atomic fluorescence spectrometry coupled with electrochemical cold vapor generation

A homemade electrochemical flow cell was adopted for the determination of methylmercury. The cold vapor of mercury atoms was generated from the surface of glassycarbon cathode through the method of electrolytic reduction and detected by atomic fluorescence spectroscopy subsequently. The operating conditions were optimized with 2 ng mL(-1) methylmercury standard solution. The caliberation curve was favorably linear when the concentrations of standard HgCH3(+) solutions were in the range of 0.2-5 ng mL(-1)(as Hg). Under the optimized conditions, the limit of detection (LOD) for methylmercury was 1.88×10(-3)ng mL(-1) and the precision evaluated by relative standard deviation was 2.0% for six times 2 ng mL(-1) standard solution replicates. The terminal analytical results of seafood samples, available from local market, showed that the methylmercury content ranged within 3.7-45.8 ng g(-1). The recoveries for methylmercury spiked samples were found to be in the range of 87.6-103.6% and the relative standard deviations below 5% (n=6) were acquired, which showed this method was feasible for real sample analysis.

Organochlorine pesticide content and distribution in coastal seafoods in Zhoushan, Zhejiang Province

Thirteen types of seafoods were collected from four counties (districts) of Zhoushan, Zhejiang Province, China and analyzed for organochlorine pesticides (OCPs). The average concentrations of OCPs in seafoods ranged from 258.3 ng g⁻¹ (lw) to 3459.6 ng g⁻¹ (lw). Hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) were the most abundant compounds in these environments and in total accounted for 8.2-62.2% and 32.1-89.0% of the total OCPs in seafoods, respectively. The total OCP contents were higher in seafoods from Shengsi and Putuo and lower in those from Dinghai and Daishan. The ratios of (DDE+DDD)/DDTs reflected a mixed input of accumulated and fresh DDTs in Shengsi, Putuo. The ratios of o,p'-DDT/p,p'-DDT in seafoods of Shengsi ranged 0.10-0.60 (mean 0.33), indicating that DDTs in seafoods of Shengsi may partly contain dicofol products and other pollutants accumulated in Yangtze Estuary. DDTs are a greater concern for ecotoxicological risk in the study area.

Evidence for Two Bacteriocins Produced by Carnobacterium piscicola and Carnobacterium divergens Isolated from Fish and Active Against Listeria monocytogenes

Lactic acid bacteria (LAB) isolated from fish products (fresh fish, smoked and marinated fish, fish intestinal tract) were screened for bacteriocin production and immunity in conditions eliminating the effects of organic acids and hydrogen peroxide. Twenty-two isolates which were found to produce bacteriocin-like compounds were identified as Carnobacteria, Lactococci and Enterococci on the basis of morphological examination, gas production from glucose, growth temperatures, configuration of lactic acid, carbohydrates fermentation and deamination of arginine. Two Carnobacteria named V1 and V41 were selected for further studies and identified by DNA-DNA hybridization as Carnobacterium piscicola and Carnobacterium divergens , respectively. Their respective bacteriocins named piscicocin V1 and divercin V41 were heat-resistant and sensitive to various proteolytic enzymes. These bacteriocins were active against Listeria monocytogenes and exhibited a different spectrum of activity against LAB. Both bacteriocins had a bactericidal and non-bacteriolytic mode of action. Maximum production of piscicocin V1 and divercin V41 in Man Rogosa Sharpe (MRS) medium broth occurred at the beginning of the stationary phase and was higher at 20°C than at 30°C. When the cultures were maintained at pH 6.5, bacteriocin production was significantly increased.