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1.
Artigo em Inglês | MEDLINE | ID: mdl-38714264

RESUMO

The present study evaluated the effect of temporal periods of hypothermia and hyperthermia, followed by an optimal temperature recovery phase on the growth, survival, and physiological response of Penaeus vannamei. Post-larvae were exposed to stress periods for 7 and 14 days at 22 °C and 32 °C each, followed by a recovery phase at 28 °C to complete seven experimental weeks, and were compared with a control group maintained at 28 °C. Weight gain, specific growth rate, feed intake, feed conversion ratio, and survival were weekly determined. Muscle, hepatopancreas, and hemolymph were sampled on the 14th day of the recovery phase for biochemical composition, and antioxidant and digestive enzyme activities determination. The shrimp presented a higher growth rate during short-term hyperthermia in contrast to shrimp under hypothermia that presented compensatory growth after thermal stress when the temperature was restored at 28 °C. Hyperthermia increased 12-13% the feed intake while this was diminished 21-29% by the hypothermia periods. Shrimp undergo metabolic adjustments following thermal stress, with short hypothermia increasing the lipase activity and lipid storage in the hepatopancreas, while short hyperthermia also enhances chymotrypsin activity and leads to higher protein and lipid accumulation. Conversely, prolonged hyperthermia induces greater energy consumption, depleting lipid and glycogen stores, while hypothermia causes scarce mobilization of energy reserves during recovery phase. Antioxidant enzyme activities were not affected by short-thermal stress (7d), while prolonged thermal stress (14d) significantly affected SOD, CAT, and GPx activities. The present study provides important insights into the physiological plasticity of P. vannamei during recovery from thermal stress.


Assuntos
Penaeidae , Animais , Penaeidae/fisiologia , Penaeidae/crescimento & desenvolvimento , Estresse Fisiológico , Hepatopâncreas/metabolismo , Antioxidantes/metabolismo , Temperatura , Hemolinfa/metabolismo
2.
Molecules ; 29(1)2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38202857

RESUMO

This work highlights the significant potential of marine toxins, particularly saxitoxin (STX) and its derivatives, in the exploration of novel pharmaceuticals. These toxins, produced by aquatic microorganisms and collected by bivalve mollusks and other filter-feeding organisms, offer a vast reservoir of chemical and biological diversity. They interact with sodium channels in physiological processes, affecting various functions in organisms. Exposure to these toxins can lead to symptoms ranging from tingling sensations to respiratory failure and cardiovascular shock, with STX being one of the most potent. The structural diversity of STX derivatives, categorized into carbamate, N-sulfocarbamoyl, decarbamoyl, and deoxydecarbamoyl toxins, offers potential for drug development. The research described in this work aimed to computationally characterize 18 STX derivatives, exploring their reactivity properties within marine sponges using conceptual density functional theory (CDFT) techniques. Additionally, their pharmacokinetic properties, bioavailability, and drug-likeness scores were assessed. The outcomes of this research were the chemical reactivity parameters calculated via CDFT as well as the estimated pharmacokinetic and ADME properties derived using computational tools. While they may not align directly, the integration of these distinct datasets enriches our comprehensive understanding of the compound's properties and potential applications. Thus, this study holds promise for uncovering new pharmaceutical candidates from the considered marine toxins.


Assuntos
Toxinas Marinhas , Saxitoxina , Biodiversidade , Disponibilidade Biológica , Preparações Farmacêuticas
3.
Mar Drugs ; 21(11)2023 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-37999421

RESUMO

Harmful algal blooms (HABs) can produce a variety of noxious effects and, in some cases, the massive mortality of wild and farmed marine organisms. Some HAB species produce toxins that are released into seawater or transferred via food webs (particulate toxin fraction). The objective of the present study was to identify the toxicological effects of subacute exposure to saxitoxin (STX) during embryonic and early larval stages in Seriola rivoliana. Eggs were exposed to dissolved 19 STX (100 µg L-1). The toxic effects of STX were evaluated via the hatching percentage, the activity of three enzymes (protein and alkaline phosphatases and peroxidase), and the expression of four genes (HSF2, Nav1.4b, PPRC1, and DUSP8). A low hatching percentage (less than 5%) was observed in 44 hpf (hours post fertilization) embryos exposed to STX compared to 71% in the unexposed control. At this STX concentration, no oxidative stress in the embryos was evident. However, STX induced the expression of the NaV1.4 channel α-subunit (NaV1.4b), which is the primary target of this toxin. Our results revealed the overexpression of all four candidate genes in STX-intoxicated lecithotrophic larvae, reflecting the activation of diverse cellular processes involved in stress responses (HSF2), lipid metabolism (PPRC1), and MAP kinase signaling pathways associated with cell proliferation and differentiation (DUSP8). The effects of STX were more pronounced in young larvae than in embryos, indicating a stage-specific sensitivity to the toxin.


Assuntos
Perciformes , Saxitoxina , Animais , Saxitoxina/toxicidade , Toxicogenética , Proliferação Nociva de Algas , Organismos Aquáticos , Larva
4.
Front Chem ; 11: 1286804, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38025068

RESUMO

Marine toxins, produced by various marine microorganisms, pose significant risks to both marine ecosystems and human health. Understanding their diverse structures and properties is crucial for effective mitigation and exploration of their potential as therapeutic agents. This study presents a comparative analysis of two hydrophilic and two lipophilic marine toxins, examining their reactivity properties and bioavailability scores. By investigating similarities among these structurally diverse toxins, valuable insights into their potential as precursors for novel drug development can be gained. The exploration of lipophilic and hydrophilic properties in drug design is essential due to their distinct implications on drug distribution, elimination, and target interaction. By elucidating shared molecular properties among toxins, this research aims to identify patterns and trends that may guide future drug discovery efforts and contribute to the field of molecular toxinology. The findings from this study have the potential to expand knowledge on toxins, facilitate a deeper understanding of their bioactivities, and unlock new therapeutic possibilities to address unmet biomedical needs. The results showcased similarities among the studied systems, while also highlighting the exceptional attributes of Domoic Acid (DA) in terms of its interaction capabilities and stability.

5.
Curr Microbiol ; 80(12): 372, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37843653

RESUMO

Phage therapy is a promising alternative to control bacterial diseases and the increasing problem of antibiotic resistance. In this sense, this research evaluates the viability of lyophilized vibrio phage vB_Pd_PDCC-1 using trehalose as a preservative excipient at different concentrations (4, 2, 1, and 0.5% w/v) and its potential for phage therapy application against a pathogenic bacteria Vibrio diabolicus in brine shrimp nauplii (Artemia franciscana). The lyophilized phages were stored at 4 and 23 °C and rehydrated using biological sterile saline solution to test their viability at days 1, 15, and 60 post-lyophilization. The results showed that trehalose is beneficial in maintaining the viability of post-lyophilization phages (without titer losses) at 4 °C and even at room temperature (23 °C). When lyophilized phages with 4% w/v trehalose concentration were stored at 23 °C, they had not titer losses among the trials; viability and titer concentration were maintained up to 60 days at log 7. The use of lyophilized phage PDCC-1 increased brine shrimp survival and reduced Vibrio concentrations. The present study has identified trehalose as a promising lyophilization excipient to effectively preserve lyophilized bacteriophages for biotechnological applications and long-term storage.


Assuntos
Bacteriófagos , Vibrio , Trealose/farmacologia , Excipientes , Myoviridae
6.
Chembiochem ; 24(22): e202300542, 2023 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-37743259

RESUMO

The current study compares the antibacterial activity of zinc oxide nanostructures (neZnO). For this purpose, two bacterial strains, Escherichia coli (ATCC 4157) and Staphylococcus aureus (ATCC 29213) were challenged in room light conditions with the aforementioned materials. Colloidal and hydrothermal methods were used to obtain the quasi-round and quasi-diamond platelet-shape nanostructures. Thus, the oxygen vacancy (VO ) effects on the surface of neZnO are also considered to assess its effects on antibacterial activity. The neZnO characterization was achieved by X-ray diffraction (XRD), a selected area electron diffraction (SAED) and Raman spectroscopy. The microstructural effects were monitored by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Furthermore, optical absorption ultraviolet visible spectrophotometry (UV-Vis) and X-ray photoelectron spectroscopy (XPS) analyses complement the physical characterization of these nanostructures; neZnO caused 50 % inhibition (IC50 ) at concentrations from 0.064 to 0.072 mg/mL for S. aureus and from 0.083 to 0.104 mg/mL for E. coli, indicating an increase in activity against S. aureus compared to E. coli. Consequently, quasi-diamond platelet-shaped nanostructures (average particle size of 377.6±10 nm) showed enhanced antibacterial activity compared to quasi-round agglomerated particles (average size of 442.8±12 nm), regardless of Vo presence or absence.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Óxido de Zinco , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Escherichia coli , Staphylococcus aureus , Espectroscopia de Infravermelho com Transformada de Fourier , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/química , Nanoestruturas/química , Difração de Raios X , Nanopartículas Metálicas/química
7.
Animals (Basel) ; 12(23)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36496769

RESUMO

Vitamin K (VK) is a fat-soluble vitamin necessary for fish metabolism and health. VK stability as dietary component during aquafeed storage and its potential effect on intestinal microbiome in fish have not yet been completely elucidated. The convenient storage conditions of aquafeeds when supplemented with phylloquinone (VK1), as well as its potential effects on the gut microbiota of Senegalese sole (Solea senegalensis) juveniles, have been explored. Experimental feeds were formulated to contain 0, 250 and 1250 mg kg-1 of VK1 and were stored at different temperatures (4, -20 or -80 °C). VK stability was superior at -20 °C for short-term (7 days) storage, while storing at -80 °C was best suited for long-term storage (up to 3 months). A comparison of bacterial communities from Senegalese sole fed diets containing 0 or 1250 mg kg-1 of VK1 showed that VK1 supplementation decreased the abundance of the Vibrio, Pseudoalteromonas, and Rhodobacterace families. All these microorganisms were previously associated with poor health status in aquatic organisms. These results contribute not only to a greater understanding of the physiological effects of vitamin K, particularly through fish intestinal microbiome, but also establish practical guidelines in the industry for proper aquafeed storage when supplemented with VK1.

8.
Appl Microbiol Biotechnol ; 105(7): 2877-2887, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33710359

RESUMO

The Seriola genus includes species of worldwide commercial importance due to its rapid growth and easy adaptability to confinement conditions. However, like other fish species, large mortalities occur during their early life stages, where the main problems are caused by opportunistic bacteria. Disease control strategies are thus urgently needed. The present study aimed to evaluate the efficacy of phage vB_Pd_PDCC-1 during the early development of longfin yellowtail (Seriola rivoliana), as well as its effect on microbial communities. This broad-host-range phage was added to the culture every 3 days starting from the egg-stage until 12 days after hatching (DAH) at a concentration of 1.41×1010 plaque-forming units (PFU) per mL and at a multiplicity of infection (MOI) of 1. The results showed positive effects (p<0.05) on egg hatching, survival, growth, and pigmentation area in treated larvae. Moreover, high-throughput sequencing analysis of 16S rRNA genes showed that phage administration did not produce significant changes (p>0.05) in the composition and structure of the associated microbiota. However, sequences affiliated to the Gammaproteobacteria class were displaced by those belonging to the Alphaproteobacteria class over time regardless of the treatment received. At the family level, there was a decrease in Rhodobacteraceae, Pseudoalteromonadaceae, and Flavobacteriaceae in both groups over time. To our best knowledge, this study represents the first attempt to evaluate the effect of a phage as a biological control agent during ontogenetic development of longfin yellowtail larvae. KEY POINTS: • Phages can be used against proliferation of Vibrio in fish cultures. • Seriola includes several important commercial fish species due to its rapid growth. • Phages do not cause significant changes in the associated microbiota.


Assuntos
Bacteriófagos , Vibrio , Animais , Bacteriófagos/genética , Peixes , Myoviridae , RNA Ribossômico 16S/genética
9.
Mol Biol Rep ; 47(12): 9627-9636, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33159677

RESUMO

Seriola rivoliana intestinal microbiota (IM) was characterised under aquaculture conditions through 16S rRNA amplicon sequencing. Specimens of 30 days after hatching (DAH) were maintained in three tanks and fed under the same environmental conditions for characterisation 15 days prior to sampling. Three fish were randomly taken from each tank; total DNA extraction of the gut microbiota was performed to characterise microbial composition and its metabolic prediction. The V3 hypervariable region of the 16S rRNA was amplified and sequenced with Illumina pair-end technology. The prokaryotic components in the S. rivoliana intestine were dominated mainly by the phyla Proteobacteria, Firmicutes, Bacteroidetes, Cyanobacteria and Actinobacteria. No significant differences in beta diversity were detected in the three samples (tanks). However in alpha diversity, they were detected in juveniles of the same cohort within the same group, as exemplified by enrichment of certain bacterial groups, mainly of the Clostridia class, which were specific in each fish within the same tank. The metabolic prediction analyses suggested that S. rivoliana IM contribute to the metabolism of amino acids, carbohydrates, lipids, and immune system. This study provides the first IM characterisation under rearing conditions of S. rivoliana-a species with broad economic potential-and contributes to novel information for potential use of probiotics in future trials.


Assuntos
Actinobacteria/metabolismo , Bacteroidetes/metabolismo , Cianobactérias/metabolismo , Firmicutes/metabolismo , Perciformes/microbiologia , Proteobactérias/metabolismo , Actinobacteria/classificação , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Aminoácidos/imunologia , Aminoácidos/metabolismo , Animais , Aquicultura , Bacteroidetes/classificação , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Metabolismo dos Carboidratos , Carboidratos/imunologia , Cianobactérias/classificação , Cianobactérias/genética , Cianobactérias/isolamento & purificação , DNA Bacteriano/genética , Firmicutes/classificação , Firmicutes/genética , Firmicutes/isolamento & purificação , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/imunologia , Imunidade Inata , Metabolismo dos Lipídeos , Lipídeos/imunologia , Perciformes/imunologia , Perciformes/metabolismo , Proteobactérias/classificação , Proteobactérias/genética , Proteobactérias/isolamento & purificação , RNA Ribossômico 16S/genética , Simbiose/imunologia
10.
Appl Microbiol Biotechnol ; 104(18): 7689-7699, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32686006

RESUMO

Debaryomyces hansenii comes of age as a new potential probiotic for terrestrial and aquatic animals. Probiotic properties, including inmunostimulatory effects, gut microbiota modulation, enhanced cell proliferation and differentiation, and digestive function improvements have been related to the oral delivery of D. hansenii. Its functional compounds, such as cell wall components and polyamines, have been identified and implicated in its immunomodulatory activity. In addition, in vitro studies using immune cells have shown standpoints on the possible recognition, regulation, and effector immune mechanisms stimulated by this yeast. This review describes historic, cutting-edge research findings, implications, and perspectives on the use of D. hansenii as a promising probiotic for animals. KEY POINTS: • Debaryomyces hansenii has probiotic effects in terrestrial and aquatic animals. • Nutritional effects could be associated to probiotic D. hansenii strains. • ß-D-Glucan and polyamines from D. hansenii are associated to probiotic properties. • Adoption by the industry is expected in the next years.


Assuntos
Debaryomyces , Probióticos , Saccharomycetales , Animais
11.
PLoS One ; 15(5): e0233064, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32407349

RESUMO

Marine bivalve hatchery productivity is continuously challenged by apparition and propagation of new diseases, mainly those related to vibriosis. Disinfectants and antibiotics are frequently overused to prevent pathogen presence, generating a potential negative impact on the environment. Recently, the use of highly diluted compounds with immunostimulant properties in marine organisms has been trailed successfully to activate the self-protection mechanisms of marine bivalves. Despite their potential as immunostimulants, little is known about their way of action. To understand their effect, a comparative transcriptomic analysis was performed with Argopecten ventricosus juveniles. The experimental design consisted of four treatments formulated from pathogenic Vibrio lysates at two dilutions: [(T1) Vibrio parahaemolyticus and Vibrio alginolyticus 1D; (T2) V. parahaemolyticus and V. alginolyticus 7C]; minerals [(T3) PhA+SiT 7C], scorpion venom [(T4) ViT 31C]; and one control (C1) hydro-alcoholic solution (ethanol 1%). The RNA sequencing (RNAseq) analysis showed a higher modulation of differentially expressed genes (DEG) in mantle tissue compared to gill tissue. The scallops that showed a higher number of DEG related to immune response in mantle tissue corresponded to T1 (V. parahaemolyticus and V. alginolyticus lysate) and T3 (Silicea terra® - Phosphoric acid®). The transcriptome analysis allowed understanding some interactions between A. ventricosus juveniles and highly-diluted treatments.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Pectinidae/genética , Pectinidae/imunologia , Animais , Aquicultura , Perfilação da Expressão Gênica , México , Pectinidae/microbiologia , RNA-Seq , Receptores de Reconhecimento de Padrão/genética , Receptores de Reconhecimento de Padrão/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vibrio/imunologia , Vibrio/patogenicidade
12.
Fish Physiol Biochem ; 46(1): 145-155, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31707568

RESUMO

Trypsin gene (try) expression levels were quantified in different organs of wild and captive tropical gar (Atractosteus tropicus) adults, and changes in expression during initial ontogeny of the species were determined. RNA was extracted from the pancreas, and cDNA was synthesized and later amplified by endpoint PCR using oligonucleotides designed from different try sequences of fish registered in GenBank. Subsequently, specific oligonucleotides were designed from the partial sequences. Gene expression was measured after RNA extraction and synthesis of the cDNA of 11 organs (liver, pancreas, stomach, esophagus, intestine, pyloric caeca, brain, muscle, gills, gonad, and kidney) of captive and wild adults. Likewise, samples of A. tropicus larvae were taken on days 0 (embryo), 5, 10, 15, 20, 25, and 30 days after hatching (DAH), the RNA was extracted, and the synthesis of cDNA was carried out to measure real-time gene expression (qPCR). The results showed that the highest relative try expression occurred mainly in the esophagus, liver, stomach, and pancreas of both wild and captive adult fish; however, captive organisms had a higher try expression level than wild fish. Although try expression during initial ontogeny was high in embryos (0 DAH), it did not reach the maximum value until 15 DAH. It was concluded that try expression levels in captive adults are due to the high protein content in the balanced feed (trout diet). The highest try expression level during larviculture was detected at 15 DAH, which indicates that A. tropicus larvae have a mature digestive system and can efficiently hydrolyze proteins from feed at this developmental stage.


Assuntos
Proteínas de Peixes/genética , Peixes/fisiologia , Tripsina/genética , Animais , Expressão Gênica
13.
Homeopathy ; 109(1): 3-13, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31454832

RESUMO

BACKGROUND: This research aimed to observe the effect of homeopathically prepared Vibrio parahaemolyticus (ViP) and V. alginolyticus (ViA) and the commercial homeopathic compound Similia (Phosphoricum acidum and Silicea terra) on the digestive enzyme activities of Seriola rivoliana juveniles under usual culture conditions. MATERIALS AND METHODS: Biochemical analysis was used to study the effect of highly diluted substances (7C potency) prepared from ViP and ViA (Treatment 1: T1) and the homeopathic compound Phosphoricum acidum and Silicea terra (Treatment 2: T2) on changes in the main digestive enzymes on weaning-state fish (WS; 30 days post-hatching [DPH]) and early juveniles (EJ; 62 DPH) versus a reference control group that received no homeopathic medicines. RESULTS: Treatment T2 significantly increased the activity of trypsin and lipase and decreased the activity of amylase, whereas treatment T1 increased the activity of chymotrypsin and reduced the activity of aminopeptidase-N in WS fish. Except for alkaline phosphatase, which was significantly reduced in the intestine, no significant differences in enzymatic activity were found between treated EJ fish and controls. The fish of the WS group had a higher growth rate with the T2 treatment. CONCLUSIONS: T1 treatment stimulated chymotrypsin in EJ fish and T2 promoted intestinal maturation of WS fish. Higher growth rate with the T2 treatment may be associated with the stimulation of trypsin activity. Thus, T2 may be applied, under hatchery conditions, during larval stages with an aim to enhance digestion and assimilation of inert food.


Assuntos
Trato Gastrointestinal/enzimologia , Homeopatia/métodos , Ácidos Fosfóricos/farmacologia , Dióxido de Silício/farmacologia , Vibrio/patogenicidade , Animais , Peixes
14.
Rev. MVZ Córdoba ; 24(3): 7328-7338, sep.-dic. 2019. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1115258

RESUMO

RESUMEN Objetivo. Estudiar el efecto de medicamentos homeopáticos sobre el crecimiento, supervivencia y microbiota del tracto gastrointestinal (TGI) de almeja Catarina Argopecten ventricosus. Materiales y Métodos. Se aplicaron cinco tratamientos homeopáticos derivados de bacterias [(T1) ViP-ViA 1D, (T2) ViP-ViA 7C], minerales [(T3) AcF-MsS 1D, (T4) PhA-SiT 7C], o venenos [(T5) ViT 31C] y tres controles: (C1) etanol diluido 1:99, (C2) etanol dinamizado 1C y (C3) agua destilada. La microbiota se determinó secuenciando la región V3-V5 del gen 16S rRNA. Resultados. El mayor crecimiento en longitud de la concha correspondió a T1 (117 µm d-1) y T2 (108 µm d-1), la mayor supervivencia a T3 y T5 y el mejor resultado global a T3. Las curvas de rarefacción de los grupos tratados y controles mostraron una clara separación. Se encontraron diferencias significativas (p≤0.05) entre filos (Proteobacteria > Actinobacteria > Firmicutes > Bacterloidetes> Chloroflexi y para los Géneros: Symbiobacterium > Microbacterium > Methylobacillus > Bacillus > Paenibacillus > Burkholderia > Nostoc > Methylobacterium > Leucobacter). El género Symbiobacterium fue dominante (p≤0.05) para T5, respecto a todos los tratamientos y grupos controles. La especie Microbacterium maritypicum (Actinobacteria) mostró la mayor abundancia relativa (p≤0.05) en T1 y T3 y Symbiobacterium toebii (Firmicutes) en T5 y T2 (p≤0.05), ambas con respecto al inicio del estudio T0. Conclusiones. Se presenta por primera vez la composición de la microbiota del TGI de A. ventricosus y la aplicabilidad potencial de la homeopatía para mejorar el rendimiento productivo y modular la microbiota gastrointestinal de la especie.


ABSTRACT Objective. To study the effect of homeopathic medicines on growth, survival and gastrointestinal (GIT) microbiota of Catarina scallop Argopecten ventricosus. Materials and methods. Five homeopathic (HOM) treatments derived from bacteria [(T1) ViP-ViA 1D, (T2) ViP-ViA 7C], minerals [(T3) AcF-MsS 1D, (T4) PhA-SiT 7C] or venoms [T5) ViT 31C] and three controls: [(C1) diluted ethanol 1:99, (C2) diluted/succussed ethanol 1C and (C3) distilled water] were evaluated (21 days) in triplicate. Microbiota was analysed by sequencing the V3-V5 region of the 16S rRNA genes. Results. The best growth in shell-length corresponded to T1 (117 µm d-1) and T2 (108 µm d-1) and the highest survival to T3 and T5, stating T3 as the best HOM-treatment. A clear separation was found in rarefaction curves of HOM-treated against un-treated control scallops. Significant differences (p≤0.05) were found for Phyla (Proteobacteria> Actinobacteria> Firmicutes> Bacterloidetes>Chloroflexi and for Genera: Symbiobacterium> Microbacterium> Methylobacillus> Bacillus> Paenibacillus> Burkholderia> Nostoc> Methylobacterium> Leucobacter). The genus Symbiobacterium was dominant in T5, finding significant differences (p≤0.05) with respect to all treatments. At species level, Microbacterium maritypicum (Actinobacteria) showed a greater relative abundance (p≤0.05) in T1 and T3 and Symbiobacterium toebii (Firmicutes) was also significantly higher (p≤0.05) in abundance in T5 and T2, both against initial T0. Conclusions. This study showed for a first time, the composition of GIT microbiota in A. ventricosus and focused on the potential applicability of homeopathy to improve overall performance and modulate the GIT microbiota of the species.


Assuntos
Bivalves , Microbiota , Homeopatia
15.
Fish Shellfish Immunol ; 92: 308-314, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31200073

RESUMO

The aims of this study were to determine the presence of phenolic compounds in Hawthorn Crataegus mexicana, species native to Mexico, nanoencapsulated (CmNano) with maltodextrin at 100 and 170 °C (CmNano100 and CmNano170) and its antioxidant and immunological effects in Longfin yellowtail Seriola rivoliana leukocytes. The phytochemical study revealed an important level of total phenolic (TPC), flavonoid (TFC) and tannin (CTC) contents in CmNano100, which correlated with a strong antioxidant capacity. CmNano100 or 170 were safe or not cytotoxic for head-kidney (HKL) and peripheral blood (PBL) leukocytes. The in vitro study demonstrated that CmNano increased the percentage of phagocytic cells, stimulated the production of reactive oxygen species, and modulated antioxidant ability by increasing superoxide dismutase activity in leukocytes with respect to the control group. In addition, CmNano100 also increased the transcription of proinflammatory cytokine IL-1ß and down-regulated MyD88 and TNF-α mRNA transcription. These results suggest that maltodextrin nanoencapsulates protected and maintained the antioxidant properties of C. mexicana. In addition, they enhanced antioxidant and immunological parameters in Longfin yellowtail S. rivoliana leukocytes. Therefore, this study provides novel insights of CmNano for its potential application as functional food in aquaculture.


Assuntos
Adjuvantes Imunológicos/farmacologia , Antioxidantes/farmacologia , Peixes/imunologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Animais , Crataegus , Peixes/metabolismo , Temperatura Alta , Leucócitos/imunologia , Nanocápsulas/administração & dosagem , Fenóis/administração & dosagem , Extratos Vegetais/administração & dosagem
16.
Front Physiol ; 10: 547, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31133878

RESUMO

In the context of intensive aquaculture, meagre (Argyrosomus regius) is one of the most important new aquaculture species in Southern Europe and several studies are focused on the optimization of its culture. Nevertheless, stressors such as handling during transport or culture maintenance may affect the immune system, thereby impairing some immune responses or provoking cellular damage. One strategy that has been used to avert this type of negative stress response is the supplementation of amino acids to improve resistance to stress. In this experiment, meagre (105.0 ± 2.6 g, mean ± standard deviation) juveniles were fed two diets for a period of 7 days, the first a commercial diet supplemented with 1% tryptophan (Trp) and second, the same commercial diet without tryptophan supplementation (control group). The effects of two types of handling stressors (air exposure and confinement/netting) on fish fed both diets was evaluated in terms of gene expression of the selected gut immunity markers, such as (1) innate immune response processes: c3 complement (c3), lysozyme (lys), and cyclooxygenase (cox2); (2) humoral immune response processes: interferon type 1 (ifn1), mx protein (mxp), interleukin 1b (il-1b), tumor necrosis factor 1a (tnf1a), and interleukin 10 (il-10); (3) antimicrobial peptides: defensin (def), hepcidin (hep), piscidin (pis), and a marker for mitochondrial respiration: glyceraldehyde 3-phosphate dehydrogenase (gapdh). Samples of the anterior intestine were collected at 1 and 6 h post-stress (hps). Results showed that in fish fed 1% Trp, the air exposure resulted in an upregulation of gene expression at 6 hps for c3, lys, cox2, ifn1, mxp, il-10 and gapdh, and il-1b and pis. The confinement/netting test for fish fed 1% Trp resulted in an upregulation of c3 and mxp and a downregulation of cox2, ifn1, il-1b, tnf1a, il-10, def, hep, and gapdh at both post-stress times (1 and 6 hps). According to the present study, dietary supplementation with 1% Trp may be considered as a proper nutritional strategy for improving tolerance and/or alleviating acute response to handling stressors.

17.
Appl Microbiol Biotechnol ; 103(5): 2339-2352, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30656393

RESUMO

Several marine Debaryomyces hansenii strains have shown probiotic effects on aquatic animals, and D. hansenii-derived ß-glucans have recently provided immunostimulant effects on goat leukocytes. This study assessed the probiotic effects of live yeast D. hansenii CBS 8339 on newborn goats administered orally, and subsequently challenged in vitro with Escherichia coli. D. hansenii CBS 8339 demonstrated the capacity to survive gastrointestinal tract conditions (bile salts and acid pH tolerance) and adhere to goat intestine. Twelve Saanen × Nubian crossbred newborn goats (2.9 ± 0.47 kg) were fed with a controlled diet or D. hansenii (0.7 g/kg body weight per day)-supplemented milk for 30 days. Blood samples of newborn goats were taken at days 15 and 30, and peripheral blood leukocytes were isolated for bacterial challenge, and immunological and antioxidant analyses. Despite cell viability was higher in leukocytes of goat kids fed with the yeast supplement, protection against E. coli challenge was not significantly affected. On the other hand, at day 15, oral administration of D. hansenii enhanced respiratory burst and catalase activity and increased superoxide dismutase activity after challenge. In contrast, at day 30, administration of the yeast supplement increased peroxidase activity and enhanced nitric oxide production and catalase activity after challenge. Finally, the yeast-supplemented diet upregulated the expression of the receptor genes TLR (2, 4, 6), modulator genes Raf.1, Syk, and Myd88, transcription factor gene AP-1, and cytokine genes IL-1ß and TNF-α only at day 15 in leukocytes from unchallenged goat kids. These results demonstrated that a short time (15 days) of orally administering the probiotic D. hansenii CBS 8339 to newborn goats stimulated innate immune and antioxidant parameters and the expression of immune-related gene signaling pathways.


Assuntos
Animais Recém-Nascidos/microbiologia , Antioxidantes/metabolismo , Debaryomyces/metabolismo , Cabras/microbiologia , Imunidade Inata/imunologia , Probióticos/metabolismo , Animais , Catalase/metabolismo , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/fisiologia , Leucócitos/citologia , Óxido Nítrico/metabolismo , Explosão Respiratória/fisiologia , Superóxido Dismutase/metabolismo , beta-Glucanas/metabolismo
18.
Fish Physiol Biochem ; 45(2): 733-742, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30536138

RESUMO

This study contributes to basic knowledge on the development of larval digestive enzyme activities of Seriola rivoliana, a carnivorous species that has shown high mortality in larval stage. The study was conducted under laboratory-controlled conditions until larvae reached 30 days after hatching (DAH). The specific activity of amylase and pepsin was analysed by spectrophotometric methods, and lipase, trypsin, chymotrypsin and alkaline phosphatase by fluorometry. The results showed that S. rivoliana larvae had different enzyme patterns depending on their developmental stage, and also when exogenous food was administered (rotifers and Artemia). At hatching (2.98 ± 0.14 mm SL), lipase, alkaline phosphatase, trypsin and chymotrypsin activities were detected, but the last two enzymes showed an activity close to zero. Trypsin, chymotrypsin, lipase and alkaline phosphatase sharply increased their activities after starting the first feeding. Amylase activity was not detected until 5 DAH (3.51 ± 0.18 mm SL) and had a peak on day 15 (4.59 ± 0.39 mm SL); no activity was observed from then on. Pepsin activity was detected approximately at 15 DAH, showing a constant increase onwards. Trypsin had a peak on day 15 and then decreased on the following days. Chymotrypsin had the highest peak at 5 DAH, then a sharp decrease on day seven (3.88 ± 0.11 mm SL), and it increased gradually until day 30 (11.71 ± 1.59 mm SL). Lipase showed the highest activity at 15 DAH and then decreased its value. Finally, alkaline phosphatase showed the highest value at 3 DAH (3.62 ± 0.06 mm SL); then, a severe decrease was observed with activity stability on the following days. In conclusion, S. rivoliana larvae had a similar pattern as that observed in other marine-carnivorous fish larvae, so it could be considered as juvenile at 20 DAH in terms of digestive physiology; based on our results and previous study, the weaning process could start after this age, which would allow establishing a co-feeding protocol using inert diet.


Assuntos
Trato Gastrointestinal/enzimologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Perciformes/crescimento & desenvolvimento , Perciformes/metabolismo , Animais , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo
19.
Dev Comp Immunol ; 88: 173-182, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30031015

RESUMO

Debaryomyces hansenii-derived ß-glucan has shown immunostimulant effect on aquaculture species and recently on goat peripheral blood leukocytes. Moreover, the marine yeast D. hansenii CBS 8339 has demonstrated to enhance fish immune response. Nonetheless, the associated immune signaling pathways induced by ß-glucan from this marine yeast have not been characterized yet. This study described the effects of ß-glucan from D. hansenii CBS 8339 against challenge with Escherichia coli and activation of possible mechanisms on goat peripheral blood leukocytes. The proton nuclear magnetic resonance spectra showed that D. hansenii had ß-(1,3)(1,6)-glucan. The phagocytic ability enhanced after E. coli challenge, and nitric oxide production increased before and after challenge in leukocytes stimulated with D. hansenii ß-glucan. In addition, an early gene expression stimulation was found related to ß-glucan recognition by TLR2 and Dectin-1 receptors, intracellular regulation by Syk, TRAF6, MyD88 and transcription factor NFκB, and effector functions of pro-inflammatory cytokine, such as IL-1ß and TNF-α. Interestingly, simulation with D. hansenii-derived ß-glucan increased leukocyte viability after E. coli challenge. In conclusion, ß-glucan from D. hansenii CBS 8339 reduced cytotoxic effects of E. coli and modulated signaling pathways and innate immune response in goat peripheral blood leukocytes.


Assuntos
Debaryomyces/química , Cabras/imunologia , Fatores Imunológicos/farmacologia , Leucócitos/imunologia , beta-Glucanas/farmacologia , Animais , Organismos Aquáticos/química , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/imunologia , Células Cultivadas , Citocinas/imunologia , Escherichia coli/imunologia , Cabras/microbiologia , Imunidade Inata/efeitos dos fármacos , Fatores Imunológicos/isolamento & purificação , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Leucócitos/microbiologia , Fagocitose/efeitos dos fármacos , Fagocitose/imunologia , Cultura Primária de Células , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , beta-Glucanas/isolamento & purificação
20.
Artigo em Inglês | MEDLINE | ID: mdl-29079225

RESUMO

Octopus bimaculoides is an important commercially fished species in the California Peninsula with aquaculture potential; however, to date limited information is available regarding its digestive physiology. The objective of this study was focused on biochemically characterizing the main enzymes involved in the digestion of O. bimaculoides. Optimum pH, temperature and thermostability were determined for amylases, lipases, trypsin and chymotrypsin; optimum pH and protease inhibitor effect were assessed for acidic and alkaline proteases, and the effect of divalent ions on trypsin and chymotrypsin activity was evaluated in enzymatic extracts from the digestive (DG) and salivary glands (SG) and crop gastric juices (GJ). High amylase activity was detected in GD and GJ whereas this activity is very low in other cephalopods. Salivary glands had the greatest activity in most of the enzyme groups, showing the importance of this organ in digestion. Optimum pH was different depending on the organ and enzyme analyzed. The optimum pH in DG was 3 showing the predominance of acidic proteases in the digestion process. All enzymes were resistant and stable at high temperatures in contrast with other marine species. Trypsin and chymotrypsin activity were highly incremented with the presence of Mg2+, Co2+, Cu2+ and Zn2+ in some tissues. The inhibitor assay showed the importance of serine proteases, metalloproteases and aspartic proteases in the digestive process of this species. This study is the first in assessing the main digestive enzymes of O. bimaculoides and in remarking the importance of other digestive enzyme groups besides proteases in octopuses.


Assuntos
Amilases/metabolismo , Quimotripsina/metabolismo , Lipase/metabolismo , Octopodiformes/metabolismo , Tripsina/metabolismo , Animais , Suco Gástrico/enzimologia , Glândulas Salivares/enzimologia
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