Monthly Variation of Tetrodotoxin Levels in Pufferfish (Lagocephalus sceleratus) Caught from Antalya Bay, Mediterranean Sea.

The silver-cheeked toadfish (Lagocephalus sceleratus), an invasive alien pufferfish species that has rapidly settled throughout the Mediterranean region, poses significant threats not only to native marine species and fisheries but also to public health due to the tetrodotoxin (TTX) they harbor. In this study, TTX concentrations in L. sceleratus from Antalya Bay in the Northeastern Mediterranean Sea were investigated using Q-TOF-LC-MS on a monthly basis over a one-year period. Pufferfish were caught by angling from May 2018 to April 2019. The TTX levels in three different tissues (gonads, liver, and muscle) of 110 pufferfish in total were determined in both male and female individuals caught for 11 months. The highest TTX mean levels generally occurred in the gonads and the lowest in the muscle samples. As regards the maximum TTX contents, the highest concentrations determined were 68.2, 34.2, and 7.8 µg/g in the gonad, liver, and muscle tissues, respectively. The highest levels were generally observed in late autumn to winter (especially in November and December) in all tissues from both genders. Female individuals were generally found to be more toxic than male individuals. The TTX levels found confirm that the consumption of L. sceleratus from Antalya Bay remains dangerous throughout the year, and thus L. sceleratus constantly constitutes an important risk source for public health.

Formulation with sage tea-loaded fish oil-based microcapsules to delay oxidation.

Fish (Engraulis encrasicolus) oil was successfully microencapsulated using sage essential oils prepared in three different concentrations as 1% (S1), 2% (S2) and 3% (S3). The microencapsulated fish oil powders fabricated with spray drying were stored at room temperature (24 ± 1 °C) in order to determine the oxidative deterioration for 12 weeks. The highest microencapsulation efficiency was observed in the S3 (60.17%) as compared with other groups. Although the changes in free fatty acid (FFA) values were defined between 6.04 and 9.29% at the end of the storage period, the lowest FFA value was found in S2 samples (p < 0.05). Among the microencapsulated samples, the highest peroxide value (PV) was measured as 20.24 meq O2/kg for S1 at the 11th week of the experimental period. Moreover, statistical differences between the control (25.93 meq O2/kg) and S1 samples were observed (p < 0.05). The rapid increase in the thiobarbituric acid (TBA) value of fish powders was delayed by microencapsulation technique fabricated with spray drying. The use of sage essential oils within this combination effectively retarded the oxidation in fish oil powders at ambient storage, indicating cost-effective for the food industry. Therefore, encapsulation of fish oils with sage oil using the spray drying technique has improved oxidation stability of fish oil and can be used for food applications.

Application of oil-in-water nanoemulsions based on grape and cinnamon essential oils for shelf-life extension of chilled flathead mullet fillets.

BACKGROUND: The effect of nanoemulsions prepared with grape seed and cinnamon essential oils on the shelf-life of flathead mullet (Mugil cephalus) fillets was evaluated by determining physicochemical (pH, free fatty acids, peroxide value, total volatile base nitrogen (TVB-N), and thiobarbituric acid reactive substances (TBARs)), sensory and microbiological (mesophilic aerobic bacteria, total psychrophilic bacteria, and Enterobacteriaceae counts) properties during 14 day storage at 2 °C. RESULTS: The nanoemulsions showed good stability and low average droplet size. The results indicated that nanoemulsion treatments significantly prolonged the shelf-life of the fillets. Treatment inhibited increases in pH and TVB-N, and retarded lipid oxidation and hydrolysis. Sensory assessment revealed that treatment induced shelf-life extension from 10 to 14 days, compared with controls. Microbiological analyses showed nanoemulsion treatment caused shelf-life extension from 10 to 12 days with reduction of microbiological contamination by up to 1 log cfu g-1 in mesophilic and 1.5 log cfu g-1 in psychrotrophic bacteria. CONCLUSION: Considering the results, grape seed and cinnamon essential oil nanoemulsions could be considered as novel antimicrobial and antioxidant materials for shelf-life extension of flathead mullet fillets during cold storage. © 2021 Society of Chemical Industry.

Assessment of the safety of dietary fish oil supplements in terms of content and quality.

The fatty acid composition of top-selling fish oil dietary supplements in the markets was compared with the content stated on product label, and their oxidative qualities and heavy metal contents were evaluated in this study. While all the capsule groups (C) confirmed the label information, it was observed that one-third of the syrup groups (S) had less than the specified content. Capsule groups generally had richer EPA and DHA contents than syrup groups in the samples examined. The peroxide values (PV) of all fish oil capsules and syrups were found in the range of 1.97-2.89 mEq/kg and 2.22-18.30 mEq/kg, respectively. As for free fatty acids (FFA) values, the C4, S6, S9, and S10 groups were above the 3% oleic acid limit recommended for high-quality oils. However, thiobarbituric acid reactive substances (TBARs) values were found below 1 mg MA/kg in all groups. All fish oil supplements were within the limits specified in terms of As (0.50-4.19 µg/g), Cd (0.14 µg/g detected for one group, C5), Cu (not detected), Fe (0.32-15.7 µg/g), and Hg (≤ 0.1 µg/g). On the other hand, two fish oil supplements from the capsule group (0.17 for C6 and 1.01 µg/g for C8) and one group from the syrup group (0.29 µg/g for S10) exceeded the recommended limit in terms of Pb (0.1 mg/kg). As a result of the research, it can be concluded that the chemical quality of fish oils in syrup form needs to be improved and their reliability in terms of fatty acid content should be increased. Considering the heavy metals, it seems significant to follow up the fish oil products more strictly.

Effects of citrus essential oils on the oxidative stability of microencapsulated fish oil by spray-drying.

The effects of citrus essential oils (orange, lemon, mandarin, and grapefruit) on the oxidative stability of microencapsulated fish oil by spray-drying were evaluated. The encapsulation efficiency of microcapsules was in the range of 42.25 and 62.43%. Twelve active substances were determined as major volatile components of citrus essential oils. The highest phenolic content was obtained from grapefruit essential oil (44.32 mg GAE/g). Lower values of thiobarbituric acid reactive substances (TBARs) were obtained for microencapsulated fish oils with essential oils compared to control. At the end of storage, the highest peroxide value (PV) was observed in the control group (25.30 meq O2/kg oil) while the lowest value was in the lemon (13.40 meq O2/kg oil) and orange group (13.91 meq O2/kg oil). The results of this study showed that citrus essential oils can be used to improve the oxidative stability of fish oil microcapsules.

The function of nanoemulsion on preservation of rainbow trout fillet.

This study was conducted to investigate the effects of nanoemulsions prepared with various concentrations of olive oil on the sensory, chemical and microbiological quality of rainbow trout fillets. The results showed that the shelf life of rainbow trout fillets were determined as 10 days for the control, 12 days for tween 80 group, 14 days for the 15% olive oil nanoemulsion group (O15) and 16 days for both 30% (O30) and 45% olive oil nanoemulsion groups (O45). It was determined that the use of olive oil suppressed the fish smell and improved the organoleptic quality of fish fillets, extending shelf life. Best sensory results were obtained from O30 and O45 treatment groups. The use of nanoemulsion had a positive effect on the biochemical parameters (TVB-N, PV, FFA, TBARs and pH), as well as inhibiting bacterial growth compared to the control group. Among nanoemulsion groups, the lowest bacteria content was found in O45 group. As a result, O30 and O45 treatment groups can be recommended for the preservation of fish fillets.

Elemental Compositions and Fatty Acid Profiles of Bogue Fish (Boops boops) From Mediterranean Coast: A Comprehensive Evaluation of the Potential Effects on Human Health.

Mersin Coast plays a quite important role in terms of biodiversity and productivity of the Mediterranean marine ecosystem. However, many effects such as industrial, urban, touristic, and agricultural factors cause pollution in this region as in many other coasts. Therefore, this study aims to discuss the potential risks and benefits of the consumption of bogue fish (Boops boops, Linnaeus, 1758) collected from the North-Eastern Mediterranean in terms of fatty acid and metal levels. The results showed that PUFA for winter and spring and SFA for summer and autumn as the predominant fractions were determined. ∑PUFA/∑SFA ratio was higher than the recommended value for each season. In addition, DHA was higher than EPA for all seasons. Nutritional and health values of lipids are maintained throughout a year, except for winter. The concentration of metal levels in the tested muscle was within the permissible limit of the world levels. Fortunately, the calculated estimated weekly intakes of metals (EWIs) were much lower than the provisional tolerable weekly intake (PTWI) for all seasons. Thus, human health risks resulting from the consumption of this fish species from Mersin Bay are unremarkable because fish muscles are not active tissues for metal accumulation. Besides, the target hazard quotient (THQ) and the total target hazard quotient (TTHQ) were < 1, indicating that there is no potential health risk for the consumers. Benefit/risk ratios for all seasons were calculated and found to be HQEFA < 1. It was determined that the cancer risk for consumers is quite low, except for heavy consumption cases. As a goal of the study, important information about the effects of seasons on the changes in lipid quality and metal properties of bogue fish was provided and discussed in detailed.

The effect of Ferula elaeochytris root extract on erectile dysfunction in streptozotocin-induced diabetic rat.

Erectile dysfunction (ED) is an important complication of diabetes. The aim of our study was to determine whether Ferula elaeochytris (FE) root extract could affect ED in streptozotocin (STZ)-induced diabetic rats. Seventy-five adult male Wistar albino rats were equally divided into five groups; control (C), FE (40 mg/kg-d), STZ-induced diabetes (60 mg/kg) (DM), diabetes + F. elaeochytris (DM + FE), and ethanol (EtOH). After 8 weeks, in vitro and in vivo parameters (intracavernosal pressure [ICP]), testicle and body weight, serum glucose levels, and histopathology were assessed. In the STZ-induced diabetic group, acetylcholine-induced endothelium-dependent relaxation responses, and electrical field stimulation-induced neurogenic and nitrergic relaxation responses were decreased significantly, while FE administration to diabetic rats reversed the decreased nitrergic and neurogenic responses. In the diabetic group, ICP/MAP (0.1375 ± 0.02 cm/H2O), spermatogenesis in testicles (53.73 ± 0.81), and testicle weights (257.8 ± 20.63) were decreased significantly; however, FE administration to diabetic rats restored the decreased values (0.350 ± 0.019 cm/H2O, 75.07 ± 0.35, and 416 ± 24.11, respectively). In the DM group, blood glucose levels were increased (411.7 ± 18.30) compared to the C group. However, FE administration to diabetic rats reduced glucose levels (230.6 ± 25.60 mg/dL) compared to the DM group. In conclusion, FE recovered neurogenic and endothelial dysfunction and decreased glucose levels in diabetic rats.

Elemental composition of pufferfish species from Northeastern Mediterranean Sea.

This study aimed at comparing the elemental levels of muscle and liver tissues of four pufferfish (Lagocephalus sceleratus, Lagocephalus spadiceus, Lagocephalus suezensis, and Torquigener flavimaculosus), which are common in the Northeastern Mediterranean Sea (Mersin Bay), in terms of sex and seasonal variables. Na, Mg, P, K, and Ca levels in the muscle tissues of pufferfish range from 1848.4 to 16495.7, 824.4 to 2684.5, 6936.2 to 20486.6, 13019.3 to 36165.5, and 276.4 to 5566.5 µg g-1, respectively. Na, Mg, P, K, and Ca levels in the liver tissues of pufferfish range from 531.8 to 6136.1, 63.8 to 899.1, 773.1 to 6677.5, 1151.4 to 10165.4, and 47.4 to 1607.7 µg g-1, respectively. The levels of macroelements in the muscle and liver tissues can be represented as K > P ≥ Na > Ca ≥ Mg and K ≥ P ≥ Na > Ca ≥ Mg, respectively. Pufferfish muscle tissue has more abundant macroelement levels than liver tissue. Fe, Cu, and Zn levels in pufferfish muscle tissues range from 21.53 to 219.42, 0.73 to 6.54, and 25.38 to 100.47 µg g-1, respectively. Fe, Cu, and Zn levels in pufferfish liver tissues range from 157.8 to 1368.6, 0.86 to 11.23, and 23.17 to 507.75 µg g-1, respectively. Levels of trace elements in the muscle and liver tissues can be represented as Zn ≥ Fe > Cu and Fe ≥ Zn > Cu, respectively. The pufferfish liver tissue is richer than muscle tissue in terms of trace element levels. Cd, Pb, As, and Cr levels in pufferfish muscle tissues range from 0.66 to 6.30, 2.17 to 20.76, 41.90 to 258.37, and 0.34 to 3.70 µg g-1, respectively. Cd, Pb, As, and Cr levels in the liver tissues of pufferfish range from 0.22 to 2.34, 0.17 to 2.27, 9.35 to 61.93, and 0.14 to 2.10 µg g-1, respectively. Levels of metal in the muscle and liver tissues can be represented as As > Pb > Cd ≥ Cr and As > Cd ≥ Pb ≥ Cr, respectively. Pufferfish muscle tissue has a higher association with liver tissue due to metal level accumulation. All pufferfish are contaminated by Cd, Pb, As, Cr, Fe, and Zn metals.

Combined impacts of oregano extract and vacuum packaging on the quality changes of frigate tuna muscles stored at 3±1°C.

AIM: The combined effects of oregano extract with vacuum packing (VP) on the quality enhancement of dark and white muscles of frigate tuna (Auxis thazard) stored as intact fillet at refrigerated (3±1°C) conditions were studied. MATERIALS AND METHODS: About 35 kg of fish were filleted without skin removal and randomly divided into two groups. One group without treatment (control) and the remaining group were dipped in a sterilized oregano extract solution for 5 min. Chemical, microbiological, sensorial, and textural analyses were carried out in each of dark and white muscles of frigate tuna fillets during storage. RESULTS: Several quality indexes were higher in dark muscle than white muscle. The sensory assessment indicated that both muscles from control had a shelf life of 12 days. Quality parameters of both muscles had the same tendency and were significantly affected by time and also by the presence of plant extract in VP. Although VP alone was sufficient to delay lipid oxidation on fish fillets, especially on dark muscle but cannot enhance the textural deterioration in both muscles. CONCLUSION: Consequently, the employment of such combination had a cumulative effect on preservation, resulting in prolonging the shelf life of both frigate tuna muscles.

Tetrodotoxin levels of three pufferfish species (Lagocephalus sp.) caught in the North-Eastern Mediterranean sea.

Tetrodotoxin (TTX) levels in Lagocephalus sceleratus (Silverstripe blaasop), Lagocephalus spadiceus (Half-smooth golden pufferfish) and Lagocephalus suezensis (Suez puffer) caught in Mersin Bay in the Northeastern Mediterranean Sea were analysed using Q-TOF LC/MS. Pufferfish were caught using trawl fishing, longlining and fishing line from December 2015 to October 2016. The TTX changes in the gonads, livers, intestines, skins and muscle tissues were evaluated according to sex and season. TTX levels for L. sceleratus and L. suezensis for all tissues were in the range of 0.69-35.6 µg/g and 0.67-3.09 µg/g, respectively. The highest TTX levels were observed in the gonads of female L. sceleratus caught in the autumn, and in the skin of L. suezensis caught in the spring but no quantifiable levels of TTX were found for L. spadiceus. In conclusion, L. sceleratus and L. suezensis species caught in the North-Eastern Mediterranean are toxic, and their consumption is unsafe.

First report on TTX levels of the yellow spotted pufferfish (Torquigener flavimaculosus) in the Mediterranean Sea.

The differences of tetrodotoxin (TTX) levels in various parts of pufferfish (Torquigener flavimaculosus) were examined in conjunction with the seasonal and sexual variations. The TTX levels in gonads, liver, intestines, skin and muscle tissue were determined using the Q-TOF LC/MS. Instrumental analysis revealed that all examined tissues from T. flavimaculosus contained high TTX concentrations. TTX levels in the gonads, liver, intestines, skin and muscle tissue of pufferfish were within the range of 5.03-100.71, 7.04-106.80, 12.59-86.30, 33.95-139.88 and 15.88-86.07 (µg/g), respectively. It was determined that in all seasons, except for summer, female individuals had higher TTX levels than males. Among all seasons, the highest level of TTX was found in winter and the lowest in autumn. Consequently, T. flavimaculosus is a highly toxic pufferfish that is dangerous for human consumption and should not be consumed under any circumstances.

The Function of Emulsions on the Biogenic Amine Formation and their Indices of Sea Bass Fillets (Dicentrarchus Labrax) Stored in Vacuum Packaging.

The impacts of emulsions based on commercial oils on the biogenic amine formation and their indices of vacuumed packed sea bass fillets were investigated. The results showed that among biogenic amines, cadaverine, putrescine, spermidine, spermine, serotonin, dopamine, and agmatine were predominant amines in sea bass fillets stored under vacuum packaging. Significant differences (P < 0.05) in biogenic amines concentrations of vacuumed packed sea bass treated with emulsions were observed. All groups contained histamine lower than 5.0 mg/100 g, regarded as the allowable limit by the U.S. Food and Drug Administration. Polyamine levels were not affected by application of emulsion. Quality index (QI) showed an increase and after 14 d of storage it decreased in all groups. The control generally seemed to higher QI value than those of treatment groups except at 14 and 18 days while soybean and corn gave lower QI among treatment groups. Only biogenic amine index correlated with sensory acceptability of vacuumed packed sea bass, indicating that this index can be used for determination of the degree of spoilage of vacuumed packed sea bass. Emulsions extended the shelf-life (approximately 2 to 4 d) of vacuumed packed sea bass fillets by inhibiting microbial growth compared to the control. PRACTICAL APPLICATION: Emulsions have become popular since they are regarded as ideal carrier for the delivery of lipophilic substances due to the ease of preparation, small particle size, their enhanced bioavailability, and long term kinetic stability. They have been proven to be self-preserving antimicrobials due to bound water in their structure and thus no available water to microorganisms. Antimicrobial emulsions have potential applications in many fields because they are inexpensive, stable, and nontoxic agents.

Tetrodotoxin levels in pufferfish (Lagocephalus sceleratus) caught in the Northeastern Mediterranean Sea.

The toxicity of tetrodotoxin (TTX) in pufferfish (Lagocephalus sceleratus) from Mersin Bay in the Northeastern Mediterranean Sea was measured using a mouse bioassay (MBA) and LC-MS-MS. Pufferfish were caught by trawl fishing, longlining and fishing line from December 2012 to October 2013. Changes in the levels of TTX in the gonads, livers, intestines, skins and muscles as a function of season and sex were determined. The gonads of female fish were toxic in all seasons (>2µg/g), whereas the gonads of male fish were only toxic in the spring and autumn. The highest TTX levels in gonads, livers, intestines and skins of female fish were 52.1, 46.2, 7.64 and 3.43µg/g, respectively, using LC-MS-MS. The TTX level in the muscle of female fish in winter was 2.83µg/g but was otherwise below the toxic limit. Consequently, it can be dangerous to consume pufferfish, including the edible muscle, from the Eastern Mediterranean Sea.

Antimicrobial Impacts of Essential Oils on Food Borne-Pathogens.

The antimicrobial activity of twelve essential oil (pine oil, eucalyptus, thyme, sage tea, lavender, orange, laurel, lemon, myrtle, lemon, rosemary and juniper) was tested by a disc diffusion method against food borne pathogens (Escherichia coli, Salmonella paratyphi A, Klebsiella pneumoniae, Yersinia enterocolitica, Pseudomonas aeruginosa, Aeromonas hydrophila, Campylobacter jejuni, Enterococcus faecalis, Staphylococcus aureus). The major components in essential oils were monoterpenes hydrocarbons, α-pinene, limonene; monoterpene phenol, carvacrol and oxygenated monoterpenes, camphor, 1,8-cineole, eucalyptol, linalool and linalyl acetate. Although the antimicrobial effect of essential oils varied depending on the chemical composition of the essential oils and specific microorganism tested, majority of the oils exhibited antibacterial activity against one or more strains. The essential oil with the lowest inhibition zones was juniper with the values varied from 1.5 to 6 mm. However, the components of essential oil of thyme and pine oil are highly active against food borne pathogen, generating the largest inhibition zones for both gram negative and positive bacteria (5.25-28.25 mm vs. 12.5-30 mm inhibition zones). These results indicate the possible use of the essential oils on food system as antimicrobial agents against food-borne pathogen. The article also offers some promising patents on applications of essential oils on food industry as antimicrobial agent.

Effect of the icing with thyme, oregano and clove extracts on quality parameters of gutted and beheaded anchovy (Engraulis encrasicholus) during chilled storage.

The effect of ice containing thyme (0.04% w/v), oregano (0.03% w/v) and clove (0.02% w/v) extracts on the quality parameters of anchovy (Engraulis encrasicholus) was assessed through the chemical, sensory and microbiological methods. According to sensory analyses, anchovy stored in ice prepared with each plant extracts had a shelf life of 12 days, while batch stored in traditional ice had a shelf life of 9 days. pH were not significantly affected by the presence of plant extracts in the ice. However, a marked antioxidant effect (P<0.05) could be detected with fish kept under plant extract icing systems, according to peroxide (PV) and thiobarbituric acid (TBA) values. Moreover, the employment of such icing systems led to lower (P<0.05) total volatile base-nitrogen (TVB-N) value and free fatty acid (FFA) formation. Thus, TVB-N proved to be a suitable index for the spoilage of anchovies during chilled storage. The employment of such icing systems also led to significantly lower counts of aerobic mesophiles and psychrotrophic bacteria in anchovy muscle with skin, as compared with the traditional ice batch. This work demonstrates that the use of ice with plant extracts for the storage of gutted and beheaded anchovy can be recommended to improve the quality and extend the shelf life.

The influences of natural zeolite (cliptinolite) on ammonia and biogenic amine formation by foodborne pathogen.

UNLABELLED: The influence of natural zeolite on biogenic amines (BAs) and ammonia (AMN) production by eight common gram negative and positive foodborne pathogens (FBP) were investigated in histidine decarboxylase broth (HDB). Presence of 1% zeolite in the HDB resulted in significantly higher AMN production. Histamine (HIS) production by gram positive bacteria was as low as 0.5 mg/L, whereas Escherichia coli produced 18.96 mg/L of HIS. The use of zeolite also significantly suppressed HIS accumulation by E. coli, Pseudomonas aeruginosa, S. paratyphi A (P < 0.05), although zeolite addition stimulated HIS production by K. pneumonia and Aeromonas hydrophila. The range of tyramine (TYR) production by gram positive bacteria was 1.19 and 4.06 mg/L for Enteroccus faecalis and Listeria monocytogenes respectively. The results of study showed that the effect of zeolite on BAs and AMN production was dependent on bacterial strains, as well as zeolite concentrations used. PRACTICAL APPLICATION: Natural zeolites are the main absorptive, low-cost material used in agriculture and industry. Although the effect of zeolite on ammonia formation in some industrial systems is well known, there is limited information regarding the impact of zeolite on biogenic amine (BA) production by foodborne pathogens. The data presented in this article will help us to understand the impact of natural zeolite on BA and ammonia production by eight common foodborne pathogens.

The effects of season and sex on fat, fatty acids and protein contents of Sepia officinalis in the northeastern Mediterranean Sea.

The effects of season and sex on the fatty acids (FAs) and proximate compositions of the mantle of the mature common cuttlefish were evaluated. The results of the proximate composition showed that the lowest lipid content was obtained from females in winter (0.74%), whereas the highest level of lipid was found in males in autumn (0.94%; p < 0.05). The protein levels of the mantle of the mature male of common cuttlefish were significantly higher (p < 0.05) than those found in female specimens. The FA compositions of each sex for all seasons ranged from 29.4% to 32.5% saturated FAs, 8.7-11.1% monounsaturated FAs and 48.2-54.6% polyunsaturated fatty acids (PUFAs). The proportions of n-3 PUFAs (44.0-50.6%) were higher than n-6 PUFAs (3.4-4.3%) regardless of sex and seasons. The levels of eicosapentaenoic acid in the mature common cuttlefish mantle in spring, autumn and winter were 15.9-17.8%, 16.3-17.2% and 15.7-16.8% while those of docosahexaenoic acid were 32.5-33.0%, 27.5-29.0% and 28.7-31.1%, respectively.