Best therapeutic practices for the use of antibacterial agents in finfish aquaculture: a particular view on European seabass (Dicentrarchus labrax) and gilthead seabream (Sparus aurata) in Mediterranean aquaculture

open7siAntibacterial therapy is still in many cases the only way to control bacterial disease outbreaks, with relevant economic issues. Nevertheless, this necessity should also be well balanced with other relevant aspects such as suitability, efficacy and refinement of the treatments but also with consumer and environmental welfare. With this aim, the literature pertaining to the use of antibacterials (i.e. oxytetracycline, oxolinic acid, flumequine and potentiated sulphonamides) in Mediterranean farmed European seabass (Dicentrarchus labrax) and gilthead seabream (Sparus aurata) was reviewed and addressed. Knowledge of drug pharmacokinetics along with the related legislation is also presented. The main criteria, technical aspects and constraints affecting the design of an appropriate antibacterial therapy are also discussed. An evaluation of available bibliography revealed the existence of considerable information on several registered antibacterials, while it is limited for others. Typically, minimum inhibitory concentrations (MIC) have been used as a reference for antibacterial selection. However, the methodologies used for MIC assessment require refinement and more sophisticated data such as epidemiological cut-off breakpoint values. Due to the characteristics of farming systems, antibacterials are mostly delivered through medicated feeds. The large number of production units and number of fish per unit, together with a limited timeframe margin for efficient therapy, makes Mediterranean gilthead seabream and European seabass, one of the best examples where the metaphylactic concept has to be considered in aquatic medicine. The information presented in this review should guide future action taken to fulfil research gaps and promote effective and prudent antibacterial practices.openRigos G.; Kogiannou D.; Padros F.; Cristofol C.; Florio D.; Fioravanti M.; Zarza C.Rigos G.; Kogiannou D.; Padros F.; Cristofol C.; Florio D.; Fioravanti M.; Zarza C

Effects of novel ingredients on growth performance in european sea bass, dicentrarchus labrax

publishedVersio

Secondary metabolites in herbal infusions of greek flora determination and evaluation of their biological properties

Since the role of diet in health is long-established, while on the other hand the prevalence of a plethora of chronic diseases increases worldwide, the need for development of dietary strategies that will result in longevity and healthy ageing is mounting. The Mediterranean diet, praised as the ‘gold standard’ in nutrition to maintain good health, includes herbs and teas, which are known for their beneficial properties since ancient times.Aiming to identify natural products with health promoting effects, many studies have been conducted on herbs and their extracts. From a nutritional point of view, studies on the analysis of herb infusions are limited, especially as refers to endemic herbs of the Greek flora.Thus, the aim herein was to identify the bioactive non-nutrient micro-constituents in infusions of 13 Greek herbs applying GC-MS and LC-DAD-MS analyses. Furthermore, the ability to exhibit antioxidant activities, the antiatherogenic effect on cultured peripheral blood mononuclear cells (PBMCs) and the antiproliferative effect and cell-death in cultured colon (HT29) and prostate (PC3) cancer cells, were investigated. Particularly in stimulated PBMCs the effect of infusions in elevated IL-6, TNF-α and MCP-1 was tested. In HT29 and PC3 cultures, inhibition in cell proliferation, influence of the cell cycle, induction of apoptosis, oxidative stress, IL-8, and activation of NF-κB were examined in presence of the infusions.Overall, chemical analyses of the infusions showed that:a) different phenolic compounds were present, thymol and carvacrol being the main representatives in most infusionsb) many glycosylated flavonoid derivatives were present in infusionsc) they exhibited high and dose dependent antioxidant activityAdditionally, as refers to the bioactivity assays, the presence of infusions in:1.stimulated PBMCs:a) regulated pro-inflammatory IL-6, TNF-α, showing anti-inflammatory and / or pro-inflammatory effects b) decreased MCP-1 (Marjoram, Melissa, Oregano, St. John’s wort, Pennyroyal, Chamomile)2.cultured HT29 and PC3:a) reduced IL-8b) downregulated NF-κB (Melissa, St. John’s wort, Thyme)c) inhibited cell proliferation by interfering with the cell cycle d) decreased cell viability inducing apoptosise) reduced intracellular GSH levelsAltogether, the antioxidant activity was strongly correlated with the phenolic content of the infusions. Regarding the pro-inflammatory activity, documented as an increase in IL-6, was associated with syringic acid, p-coumaric acid and sinapic acid, while the anti-inflammatory activity, expressed as a decrease in MCP-1, was correlated to p-coumaric acid. The dependency of cancer cells on their antioxidant systems is nowadays well-established and it represents a specific vulnerability that could be exploited to induce targeted cell death by. increasing oxidative stress above the toxicity threshold. Based on these, it was investigated whether the modification of redox homeostasis through the increment of intracellular ROS levels and the decrement of (endogenous) antioxidant defense, was the mechanism responsible for the apoptotic effect of infusions. Although no significant effect in ROS was detected, the redox homeostasis of cancer cells was altered by intracellular glutathione (GSH) depletion.Δεδομένου ότι είναι επιβεβαιωμένη η επίδραση της διατροφής στην υγεία και ότι ο επιπολασμός πολλών χρόνιων νοσημάτων αυξάνει παγκοσμίως, κρίνεται αναγκαία η ανάπτυξη διατροφικών συστάσεων που θα συμβάλουν στην επίτευξη όχι μόνο μακροζωίας, αλλά και υγιούς γήρατος. Η Μεσογειακή διατροφή, πρότυπη για τη διατήρηση της καλής υγείας, περιλαμβάνει μεταξύ άλλων στοιχείων και τα βότανα, οι ευεργετικές ιδιότητες των οποίων είναι γνωστές από την αρχαιότητα.Στην προσπάθεια ανάδειξης φυσικών προϊόντων με βιοπροστατευτική δράση έχουν γίνει πολλές μελέτες σε βότανα και εκχυλίσματα αυτών. Από διατροφική άποψή, οι μελέτες που αφορούν στην ανάλυση των αφεψημάτων των βοτάνων είναι περιορισμένες ενώ ελάχιστες από αυτές έχουν ως αντικείμενο τα ενδημικά βότανα της Ελληνικής χλωρίδας. Σκοπός της παρούσας μελέτης ήταν ο προσδιορισμός των βιοδραστικών μη-θρεπτικών μικροσυστατικών σε αφεψήματα 13 Ελληνικών βοτάνων με εφαρμογή των χρωματογραφικών τεχνικών GC-MS και LC-DAD-MS. Διερευνήθηκε επίσης η ικανότητά τους να επιδεικνύουν αντιοξειδωτική δράση και να επιδρούν σε καλλιέργειες μονοπύρηνων κυττάρων του περιφερικού αίματος (PBMCs) υπό συνθήκες φλεγμονής και σε καλλιέργειες καρκινικών κυττάρων του παχέος εντέρου (ΗΤ29) και του προστάτη (PC3). Στα PBMCs εξετάσθηκε η επίδραση (α) στα επίπεδα έκκρισης των IL-6 και TNF-α και (β) στα επίπεδα έκκρισης της MCP-1. Στα HT29 και PC3 εξετάστηκε η επίδραση (α) στον κυτταρικό πολλαπλασιασμό, (β) στον κυτταρικό κύκλο, (γ) στην απόπτωση, (δ) στα επίπεδα οξειδωτικού στρες, (ε) στα επίπεδα της IL-8, και (στ) στα επίπεδα ενεργοποίησης του NF-κΒ.Από την αξιολόγηση των αποτελεσμάτων των χημικών αναλύσεων προέκυψε ότι τα αφεψήματα των βοτάνων:α) περιείχαν φαινολικά συστατικά με κυριότερους εκπροσώπους στην πλειοψηφία τους, τις τερπενοειδείς φαινόλες θυμόλη και καρβακρόληβ) περιείχαν γλυκοζυλιωμένα παράγωγα φλαβονοειδώνγ) παρουσίασαν ισχυρή και δοσοεξαρτώμενη αντιοξειδωτική δράση Από την αξιολόγηση των αποτελεσμάτων ελέγχου της βιοδραστικότητας, τα αφεψήματα που επέδρασαν σε:1.PBMCs:α) τροποποίησαν τα επίπεδα έκκρισης των κυτταροκινών IL-6 και TNF-α, παρουσιάζοντας κατά περιπτώσεις αντιφλεγμονώδη ή/και προφλεγμονώδη δράσηβ) μείωσαν τα επίπεδα της MCP-1 κατά περιπτώσεις (Μαντζουράνα, Μελισσόχορτο, Ρίγανη, Σπαθόχορτο, Φλισκούνι, Χαμομήλι)2.ΗΤ29 και PC3:α) μείωσαν τα επίπεδα της IL-8β) μείωσαν τα επίπεδα του NF-κΒ κατά περιπτώσεις (Μελισσόχορτο, Σπαθόχορτο, Θυμάρι)γ) ανέστειλαν τον κυτταρικό πολλαπλασιασμό, παρεμβαίνοντας σε φάσεις του κυτταρικού κύκλουδ) μείωσαν τη βιωσιμότητα των κυττάρων επάγοντας την απόπτωσηε) μείωσαν τα επίπεδα της ενδοκυττάριας γλουταθειόνηςΣυνολικά φάνηκε ότι η αντιοξειδωτική δράση συσχετίσθηκε ισχυρά με το φαινολικό περιεχόμενο των αφεψημάτων. Αναφορικά με την προφλεγμονώδη δράση που καταγράφηκε από την αύξηση των επιπέδων της IL-6, αυτή συσχετίσθηκε με το συριγγικό οξύ, το p-κουμαρικό οξύ και το σιναπικό οξύ, ενώ η αντιφλεγμονώδης δράση που εκφράστηκε ως μείωση των επιπέδων της MCP-1, αυτή συσχετίσθηκε με την παρουσία του p-κουμαρικού οξέος. Η εξάρτηση των καρκινικών κυττάρων από τα αντιοξειδωτικά τους συστήματα είναι επιβεβαιωμένη και μπορεί να αξιοποιηθεί για την πρόκληση του κυτταρικού θανάτου, μέσω αύξησης του οξειδωτικού στρες πάνω από το όριο τοξικότητας. Με βάση τα παραπάνω, ο υποκείμενος μηχανισμός δράσης που διερευνήθηκε ήταν η τροποποίηση της οξειδοαναγωγικής ομοιόστασης, μέσω αύξησης των ενδοκυττάριων επιπέδων των ROS και μείωσης της αντιοξειδωτικής τους άμυνας στις δύο κυτταρικές σειρές. Από τη συνολική αξιολόγηση των αποτελεσμάτων προέκυψε ότι, τα αφεψήματα των βοτάνων δεν επάγουν την παραγωγή δραστικών ενώσεων οξυγόνου αλλά μεταβάλουν τα επίπεδα οξειδωτικού στρες των HT29 και PC3 μέσω της μείωσης της ενδοκυττάριας γλουταθειόνης (GSH)

Evaluation of Praziquantel Efficacy against Zeuxapta seriolae Infections in Greater Amberjack, Seriola dumerili

The aim of this study was to evaluate the efficacy of dietary praziquantel (PZQ), a promising fish anthelminthic, against Zeuxapta seriolae, a lethal ectoparasite of greater amberjack (Seriola dumerili Risso) farmed in the Mediterranean and elsewhere. The trial was carried out in small cages (3 m3) in situ, harbouring fish (125 ± 14 g) naturally infected with Z. seriolae, at 25 ± 1 °C water temperature. Praziquantel-medicated diet (150 mg PZQ/kg fish) was delivered for three days against a control group. Measurement of both adults and oncomiracidia of Z. seriolae in sampled gill arches revealed significant differences between the tested groups (PZQ: 19.3 ± 9.8 vs. Control: 3.8 ± 6.3). Considering an estimated efficacy of 80.4% in the medicated fish, the present study indicates that oral PZQ treatments can confront Z. seriolae infections considerably in farmed greater amberjack and, perhaps, replace the commonly used hydrogen peroxidase baths

Phenolic profiles and antioxidant and anticarcinogenic activities of Greek herbal infusions; Balancing delight and chemoprevention?

Total phenolic content, antioxidant activity and phenolic profiles of six herbal infusions - namely rosemary, Cretan dittany, St. John's Wort, sage, marjoram and thyme were assayed. Additionally, the infusion anticarcinogenic effect as to their ability to (a) scavenge free radicals, (b) inhibit cell growth, (c) decrease IL-8 levels and (d) regulate p65 subunit in epithelial colon cancer (HT29) and prostate (PC3) cancer cells was investigated. LC-DAD-MS and GC-MS analyses showed major qualitative and quantitative differences in phenolic profiles of the infusions. All herbal infusions exhibited antiradical activity which correlated strongly with their total phenolic content. Infusions exhibited the potential to inhibit cell growth and to reduce IL-8 levels in HT29 colon and PC3 prostate cancer cells. The regulation reported in p65 subunit in HT29 treated with St John's Wort and in PC3 treated with thyme might point to the NF-jB as the molecular target underlying the effect of these infusions. © 2013 Elsevier Ltd. All rights reserved

Consumer Perception of Freshness and Volatile Composition of Fresh Gilthead Seabream and Seabass in Active Packaging with and without CO2-Emitting Pads

Active packaging with CO2-emitters (pads) has recently been used for shelf-life extension of fresh fish. The aim of this study was to identify consumer attitudes towards fresh fish packaging, to examine whether Greek consumers prefer active packaging with pad over active packaging without pad, to investigate any perceived differences in the sensory freshness of the fish, and to relate consumer perception to volatile composition of fish fillets. In total, 274 consumers participated in the study which included freshness sensory evaluation of gilthead seabream (Sparus aurata) and seabass (Dicentrarchuslabrax), whole-gutted and filleted, raw and cooked, at high quality and at the end of high-quality shelf-life. Samples were packed under modified atmosphere either with a pad or without. Results showed that consumers preferred packages with pads, especially at the end of high quality shelf-life. They perceived raw samples packed with a pad to be fresher and closer to the ideal product, and also had a higher purchase intention towards them. Cooked samples were not perceived differently. Consumers’ perception was in accordance with the GC-MS findings in the volatile compounds that function as freshness or spoilage indicators. Most participants were positive towards fresh fish packaging although they usually buy unpacked fresh fish. Our results suggest that active packaging with CO2 emitters contribute to freshness preservation and that it has a positive potential in the Greek market

Sensory and chemical freshness of rainbow trout (Oncorhynchus mykiss),gilthead sea bream (Sparus aurata), and carp (Cyprinus carpio) as affected by dietary fishmeal / fish oil replacement

International audienc

Impact of diets containing plant raw materials as fish meal and fish oil replacement on rainbow trout (Oncorhynchus mykiss), gilthead sea bream (Sparus aurata), and common carp (Cyprinus carpio) freshness

The present study aimed to evaluate whether the total or high substitution of fish meal (FM) and fish oil (FO) by sustainable plant raw materials (plant meal and oils) in long-term feeding for rainbow trout, gilthead sea bream, and common carp can result in spoilage alterations during ice storage. These three species were fed throughout their whole rearing cycle with plant-based diets and compared to counterparts that received FM/FO-based diets or commercial-like diets. Sensory QIM schemes adopted for these species and ATP breakdown products ( 835 c3e-value and components) were used to evaluate the freshness. Sensory acceptability of 14, 15, and 12 days was found for rainbow trout, gilthead sea bream, and common carp, respectively. This corresponded to 835 c3e-values of approximately 80%, 35%, and 65% for rainbow trout, gilthead sea bream, and common carp, respectively. No major effect of dietary history on postmortem shelf life was shown for gilthead sea bream and common carp; neither sensory-perceived nor chemical freshness showed diet-related differences. Rainbow trout fed with the plant-based diet exhibited slightly worse sensory freshness than fish fed with FM/FO-based diets, at the end of shelf life.These findings imply that FM and FO can be successfully substituted without major impacts on shelf life of fish