Pediococcus acidolacticiandPediococcus pentosaceusisolated from a rainbow trout ecosystem have probiotic and ABF1 adsorbing/degrading abilitiesin vitro

Abstract

Probiotics are being used in biological control of bacterial pathogens, as an alternative to antibiotics, to improve health and production parameters in fish farming. Fish farming production is severely affected by aflatoxins (AFs), which are a significant problem in aquaculture systems. Aflatoxins exert substantial impact on production, causing disease with high mortality and a gradual decline of reared fish stock quality. Some aspects of aflatoxicosis in fish, particularly its effects on the gastrointestinal tract, have not been well documented. The aim of the present study was to evaluate probiotic properties of lactic acid bacterial (LAB) strains isolated from rainbow trout intestine and feed. Moreover, AFB-binding and/or degrading abilities were also evaluated to assess their use in the formulation of feed additives. Growth at pH 2, the ability to co-aggregate with bacterial pathogens, inhibition of bacterial pathogens, and determination of the inhibitory mechanism were tested. Aflatoxin B (AFB) adsorption and degradation ability were also tested. All strains were able to maintain viable (10 cells ml) at pH 2. Pediococcus acidilactici RC001 and RC008 showed the strongest antimicrobial activity, inhibiting all the pathogens tested. The strains produced antimicrobial compounds of different nature, being affected by different treatments (catalase, NaOH and heating), which indicated that they could be HO organic acids or proteins. All LAB strains tested showed the ability to coaggregate pathogenic bacteria, showing inhibition percentages above 40%. Pediococcus acidilactici RC003 was the one with the highest adsorption capacity and all LAB strains were able to degrade AFB with percentages higher than 15%, showing significant differences with respect to the control. The ability of some of the LAB strains isolated in the present work to compete with pathogens, together with stability against bile and gastric pH, reduction of bioavailability and degradation of AFB, may indicate the potential of LAB for use in rainbow trout culture.

Sustainable plant-based diets promote rainbow trout gut microbiota richness and do not alter resistance to bacterial infection

“…These results are in line with previous studies that also showed that the inclusion of terrestrial plant proteins in rainbow trout diet induces a significant increase of several LAB among other microorganisms [ 21 , 39 , 44 , 45 ]. Interestingly, several strains belonging to the genus Pediococcus displayed probiotic properties in vitro [ 46 ] and in vivo in rainbow trout [ 47 ]. In other fish species, feeds containing plant derivate indigestible fiber and fermentable polysaccharides were associated with an increase of LAB that can utilize such substrates for their metabolism and growth [ 48 – 50 ].…”

Occurrence and Dynamism of Lactic Acid Bacteria in Distinct Ecological Niches: A Multifaceted Functional Health Perspective

“…Certain Pediococcus spp. have mycotoxin adsorbing and degrading properties ( Martinez et al, 2017 ). Reducing aflatoxin bioavailability was reported in rats ( Hernandez-Mendoza et al, 2011 ; Nikbakht Nasrabadi et al, 2013 ) and in mice ( Jebali et al, 2015 ), but yet no clinical data are available on the use of LAB as detoxifying probiotics in humans.…”

Aflatoxin B1adsorption/desorption dynamics in the presence ofLactobacillus rhamnosusRC007 in a gastrointestinal tract-simulated model

“…, ) and probiotic Pediococcus acidolactici and P. pentosaceus (Martínez et al . ). The use of these micro‐organisms at a commercial level requires a design of the culture medium, one of the most important tasks within the biological technology, evaluating the use of economic substrates for the biomass production at a large scale, allowing also the conservation of the biological properties previously demonstrated in the laboratory.…”