Microalgae and cyanobacteria as microbial substrate and their influence on the potential postbiotic capability of a bacterial probiotic.

Postbiotics are metabolic by-products from microorganisms that provide health benefits to the host. Their secretion can be influenced by various conditions affecting bacterial metabolism. This study presents a novel approach for producing potential postbiotics, specifically extracellular products (ECPs), from the probiotic strain Shewanella putrefaciens SpPdp11, grown under different culture conditions.

Microalgal and Cyanobacterial Biomasses Modified the Activity of Extracellular Products from Bacillus pumilus: An In Vitro and In Vivo Assessment.

This study investigates the postbiotic potential of extracellular products (ECPs) from Bacillus pumilus strains cultivated on microalgae-supplemented media. We assessed enzymatic and antimicrobial activities to select ECPs that enhance the digestive processes in gilthead seabream. Additionally, we explored the in vitro enzymatic capacity of the chosen postbiotics to hydrolyze macromolecules in microalgae.

An ex vivo Approach in European Seabass Leucocytes Supports the in vitro Regulation by Postbiotics of Aip56 Gene Expression of Photobacterium damselae subsp. piscicida.

Shewanella putrefaciens Pdp11 (SpPdp11) is a probiotic strain assayed in aquaculture; however, its postbiotic potential is unknown. Postbiotics are bacterial metabolites, including extracellular products (ECPs) that improve host physiology and immunity. Their production and composition can be affected by different factors such as the growing conditions of the probiotics.

Dietary Effects of a Short-Term Administration of Microalgae Blend on Growth Performance, Tissue Fatty Acids, and Predominant Intestinal Microbiota in .

Given the potential of microalgae as new aquafeed ingredients, this study focuses on using a blend of microalgae, , , and , as a dietary ingredient for feeding juveniles. The growth performance, carcass composition, tissue fatty acid profile, and intestinal microbiota were evaluated after a 30 day-feeding period. A microalgae-free diet was used as control, and three experimental diets were formulated containing 5%, 15%, and 25% of the microalgae blend (MB-5%, MB-15%, and MB-25%, respectively).

Pathogenic strains of contain plasmids that are absent in the probiotic strain Pdp11.

Pdp11 is a strain described as a probiotic for use in aquaculture. However, includes strains reported to be pathogenic or saprophytic to fish. Although the probiotic trait has been related to the presence of a group of genes in its genome, the existence of plasmids that could determine the probiotic or pathogenic character of this bacterium is unknown.

Solar disinfection - An appropriate water treatment method to inactivate faecal bacteria in cold climates.

Solar disinfection (SODIS) is an inexpensive drinking water treatment method applied in tropical and sub-tropical low-income countries. However, it has been unclear whether it functions adequately also in colder climates. To investigate this issue, SODIS experiments were performed in the humid continental climate of Finland by exposing faecally contaminated drinking water to natural solar radiation at different water temperatures (8-23 °C) and UV intensities (12-19 W/m) in polyethylene (PE) bags.

Immunomodulation and skin microbiota perturbations during an episode of chronic stress in gilthead seabream.

Fish stress is a major concern in the aquaculture industry. Many stressors coming from routine practices can predispose fish to compromised growth, immunity and overall health. This study focuses on the characterization of the skin microbiota using next generation sequencing (NGS) platform by targeting a genomic marker 16S and to determine growth performance and immune status of gilthead seabream (Sparus aurata) during an episode of chronic stress.

Vaccination of Gilthead Seabream After Continuous Xenoestrogen Oral Exposure Enhances the Gut Endobolome and Immune Status GPER1.

In fish culture settings, the exogenous input of steroids is a matter of concern. Recently, we unveiled that in the gilthead seabream (), the G protein-coupled estrogen receptor agonist G-1 (G1) and the endocrine disruptor 17α-ethinylestradiol (EE) are potent modulators in polyreactive antibody production. However, the integral role of the microbiota upon immunity and antibody processing in response to the effect of EE remains largely unexplored.

Alteration of the Immune Response and the Microbiota of the Skin during a Natural Infection by in European Seabass ().

Disease outbreaks continue to represent one of the main bottlenecks for the sustainable development of the aquaculture industry. In marine aquaculture, many species from the genus are serious opportunistic pathogens responsible for significant losses to producers. In this study, the effects on the immune response and the skin microbiota of European sea bass () were studied after a natural disease outbreak caused by .

A Tentative Study of the Effects of Heat-Inactivation of the Probiotic Strain Ppd11 on Senegalese Sole () Intestinal Microbiota and Immune Response.

Concerns about safety, applicability and functionality associated with live probiotic cells have led to consideration of the use of non-viable microorganisms, known as paraprobiotics. The present study evaluated the effects of dietary administration of heat-inactivated cells of the probiotic strain Ppd11 on the intestinal microbiota and immune gene transcription in . Results obtained were evaluated and compared to those described after feeding with viable Pdp11 cells.

Diet, Immunity, and Microbiota Interactions: An Integrative Analysis of the Intestine Transcriptional Response and Microbiota Modulation in Gilthead Seabream () Fed an Essential Oils-Based Functional Diet.

Essential oils (EOs) are promising alternatives to chemotherapeutics in animal production due to their immunostimulant, antimicrobial, and antioxidant properties, without associated environmental or hazardous side effects. In the present study, the modulation of the transcriptional immune response (microarray analysis) and microbiota [16S Ribosomal RNA (rRNA) sequencing] in the intestine of the euryhaline fish gilthead seabream () fed a dietary supplementation of garlic, carvacrol, and thymol EOs was evaluated. The transcriptomic functional analysis showed the regulation of genes related to processes of proteolysis and inflammatory modulation, immunity, transport and secretion, response to cyclic compounds, symbiosis, and RNA metabolism in fish fed the EOs-supplemented diet.

Probiotic (SpPdp11) as a Fish Health Modulator: A Review.

Aquaculture is considered one of the largest food production sectors in the world. Probiotics have long been considered as a beneficial tool in this industry since these microorganisms improve the welfare of different fish species by modulating several physiological functions, such as metabolism, digestion, immune response, stress tolerance, and disease resistance, among others. SpPdp11, a probiotic isolated from the skin of healthy gilthead seabream, has been the center of attention in a good number of studies since its discovery.

A comparison of photolytic, photochemical and photocatalytic processes for disinfection of recirculation aquaculture systems (RAS) streams.

The development of technologically advanced recirculation aquaculture systems (RAS) implies the reuse of water in a high recirculation rate (>90%). One of the most important phases for water management in RAS involves water disinfection in order to avoid proliferation of potential pathogens and related fish diseases. Accordingly, different approaches have been assessed in this study by performing a comparison of photolytic (UV-LEDs) at different wavelengths (λ = 262, 268 and 262 + 268 nm), photochemical (UV-LEDs/HO, UV-LEDs/HSO and UV-LEDs/SO) and photocatalytic (TiO/SiO/UV-LEDs and ZnO/SiO/UV-LEDs) processes for the disinfection of water in RAS streams.

Transcription of IVIAT and Virulence Genes in Subsp. Infecting .

subsp. () is responsible for disease outbreaks in marine aquaculture worldwide. , a valuable fish species for aquaculture in the south of Europe, is frequently affected by this pathogen.

Dietary administration of the probiotic Shewanella putrefaciens Pdp11 promotes transcriptional changes of genes involved in growth and immunity in Solea senegalensis larvae.

Senegalese sole (Solea senegalensis) has been proposed as a high-potential species for aquaculture diversification in Southern Europe. It has been demonstrated that a proper feeding regimen during the first life stages influences larval growth and survival, as well as fry and juvenile quality. The bacterial strain Shewanella putrefaciens Pdp11 (SpPdp11) has shown very good probiotic properties in Senegalese sole, but information is scarce about its effect in the earliest stages of sole development.

Mucus glycosylation, immunity and bacterial microbiota associated to the skin of experimentally ulcered gilthead seabream (Sparus aurata).

Interest in fish skin immunity and its associated microbiota has greatly increased among immunologists. The objective of this study is to know if skin ulcers may be associated with changes in the mucus composition and microbial diversity. The abundance of terminal carbohydrates, several enzymes (protease, antiprotease, peroxidase, lysozyme) and total immunoglobulin M levels were evaluated in skin mucus of experimentally ulcered gilthead seabream (Sparus aurata L.

Insights into the fecal microbiota of captive Iberian lynx (Lynx pardinus).

The Iberian lynx (Lynx pardinus) is an endangered species restricted to several areas of Spain and Portugal. Its low genetic diversity likely provokes immune depression and high susceptibility to infectious diseases. The intestinal microbiota is closely related to host health and nutrition.

Terminal carbohydrates abundance, immune related enzymes, bactericidal activity and physico-chemical parameters of the Senegalese sole (Solea senegalensis, Kaup) skin mucus.

Recently, interest in mucosal surfaces, more specifically fish skin and its secreted mucus, has greatly increased among immunologists. The abundance of terminal carbohydrates, several enzymes (proteases, lysozyme, peroxidase, alkaline phosphatase, esterases and ceruloplasmin), bactericidal activity against fish pathogenic and non-pathogenic bacteria and several physico-chemical parameters (protein concentration, pH, conductivity, redox potential, osmolarity, density and viscosity) in the skin mucus of Senegalese sole (Solea senegalensis, Kaup) have been evaluated. Present results evidence the abundance of N-acetylneuraminic acid, mannose, glucose and N-acetyl-galactosamine in skin mucus.

Effects on intestinal microbiota and immune genes of Solea senegalensis after suspension of the administration of Shewanella putrefaciens Pdp11.

The interaction host-intestinal microbiota is essential for the immunological homeostasis of the host. Probiotics, prebiotics and synbiotics are promising tools for the manipulation of the intestinal microbiota towards beneficial effects to the host. The objective of this study was to evaluate the modulation effect on the intestinal microbiota and the transcription of genes involved in the immune response in head kidney of Solea senegalensis after administration of diet supplemented with the prebiotic alginate and the probiotic Shewanella putrefaciens Pdp11 CECT 7627 (SpPdp11).

Changes in intestinal morphology and microbiota caused by dietary administration of inulin and Bacillus subtilis in gilthead sea bream (Sparus aurata L.) specimens.

Changes produced in gilthead sea bream (Sparus aurata L.) intestinal morphology and microbiota caused by dietary administration of inulin and Bacillus subtilis have been studied. Gilthead sea bream specimens were fed diets containing 0 (control), inulin (10 g kg(-1)), B.

Histological alterations and microbial ecology of the intestine in gilthead seabream (Sparus aurata L.) fed dietary probiotics and microalgae.

The effects on histology and microbial ecology in gilthead seabream (Sparus aurata) intestine caused by dietary probiotic and microalgae were studied. Fish were fed non-supplemented (C, control) or supplemented diets with Tetraselmis chuii, Phaeodactylum tricornutum and Bacillus subtilis single or combined (diets T, P, B, BT and BP) for 4 weeks. Curiously, fish fed the experimental diets showed similar morphological alterations when studied by light and electron microscopy and significant signs of intestinal damage were detected.

Intestinal microbiota diversity of the flat fish Solea senegalensis (Kaup, 1858) following probiotic administration.

Pleuronectiforms are an important group of fish, and one of their species, Solea senegalensis (Kaup 1858), has been extensively studied at different levels, although information about its intestinal microbiota and the effects of different factors on it is very scarce. Modern aquaculture industry demands strategies which help to maintain a microbiologically healthy environment and an environmentally friendly aquaculture. In this context, probiotics seem to offer an attractive alternative.