Saccharomyces cerevisiae as a probiotic agent and a possible aflatoxin B1 adsorbent in simulated fish intestinal tract conditions

The effects of probiotic-based additives on aflatoxin intoxication in Piaractus mesopotamicus: a study of liver histology and metabolic performance

Mycotoxins, produced by fungi, can contaminate fish food and harm their health. Probiotics enhance immune balance and primarily function in the animal intestine. This study aimed to assess aflatoxin's impact on Piaractus mesopotamicus and explore probiotic-based additive (PBA) benefits in mitigating these effects, focusing on antioxidant activity, biochemical indices, and hepatic histopathology. Two experiments were conducted using P. mesopotamicus fry. The first experimental assay tested various levels of aflatoxin B1 (0.0, 25.0, 50.0, 100.0, 200.0, and 400.0 µg kg-1) over a 10-day period. The second experimental assay examined the efficacy of the probiotic (supplemented at 0.20%) in diets with different levels of aflatoxin B1 (0.0, 25.0, and 400.0 µg kg-1) for 15 days. At the end of each assay, the fish underwent a 24-hour fasting period, and the survival rate was recorded. Six liver specimens from each treatment group were randomly selected for metabolic indicator assays, including superoxide dismutase, catalase, alanine aminotransferase, aspartate aminotransferase, and albumin. Additionally, histopathological analysis was performed on six specimens. The initial study discovered that inclusion rates above 25.0 µg kg-1 resulted in decreased activity of AST (aspartate aminotransferase), ALT (alanine aminotransferase), ALB (albumin), CAT (catalase), and SOD (superoxide dismutase), accompanied by liver histopathological lesions. In the second study, the inclusion of PBA in diets contaminated with AFB1 improved the activity of AST and ALT up to 25.0 µg kg-1 of AFB1, with no histopathological lesions observed. The study demonstrated the hepatoprotective effects of PBA in diets contaminated with AFB1. The enzyme activity and hepatic histopathology were maintained, indicating a reduction in damage caused by high concentrations of AFB1 (400.0 µg kg-1 of AFB1). The adverse effects of AFB1 on biochemical and histopathological parameters were observed from 25.0 µg kg-1 onwards. Notably, PBA supplementation enhanced enzymatic activity at a concentration of 25 µg kg-1 of AFB1 and mitigated the effects at 400.0 µg kg-1 of AFB1. The use of PBAs in pacu diets is highly recommended as they effectively neutralize the toxic effects of AFB1 when added to diets containing 25.0 µg kg-1 AFB1. Dietary inclusion of aflatoxin B1 at a concentration of 25.0 µg kg-1 adversely affects the liver of Piaractus mesopotamicus (Pacu). However, the addition of a probiotic-based additive (PBA) to the diets containing this concentration of aflatoxin neutralized its toxic effects. Therefore, the study recommends the use of PBAs in Pacu diets to mitigate the adverse effects of aflatoxin contamination.

The protective effects of Saccharomyces cerevisiae on the growth performance, intestinal health, and antioxidative capacity of mullet (Liza ramada) fed diets contaminated with aflatoxin B1

Plant protein ingredients are increasingly included in mullet feeds and are expected to be contaminated with mycotoxins (AFB1). Thus, this study investigated the protective role of Saccharomyces cerevisiae against oxidative stress and hepato-renal malfunction induced by AFB1 contamination in mullets. Four diets were formulated, where the first was kept as the control diet, and the second was supplemented with S. cerevisiae at 5 × 106 cells/g. The third diet was supplied with AFB1 at 1 mg/kg, and the fourth was supplemented with S. cerevisiae and AFB1. Mullet fed the control or both AFB1 and S. cerevisiae (yeast/AFB1) had similar FBW, WG, SGR, and FCR (P˃0.05). Mullet treated with S. cerevisiae without AFB1 contamination showed the highest FBW, WG, and SGR (P<0.05), while fish in the AFB1 group had lower FBW, WG, and SGR and higher FCR than fish in the control and yeast/AFB1 groups (P<0.05). Using yeast with AFB1 prevented pathological hazards and improved intestinal structure. Further, yeast combined with AFB1 reduced the degenerative changes and enhanced the histological structure except for a mild inflammatory reaction around the bile duct. Fish in the control or yeast/AFB1 group had higher HB, PCV, RBCs, and WBCs than fish in the AFB1 group (P<0.05). Fish fed the control, or the yeast/AFB1 diets had similar total protein and albumin levels with higher values than fish contaminated with AFB1 (P<0.05). Fish fed the control and yeast/AFB1 diets had similar ALT, AST, urea, and creatinine levels (P˃0.05) and were lower than fish contaminated with AFB1. Additionally, fish fed the control and yeast/AFB1 diets had similar CAT, GPx, SOD, and MDA (P˃0.05) and were lower than fish contaminated with AFB1 (P<0.05). In conclusion, incorporating S. cerevisiae ameliorated the negative impacts of AFB1 toxicity on mullets’ growth, hepato-renal function, and antioxidative capacity.

Ochratoxin A as alarming health in livestock and human: A review on molecular interactions, mechanism of toxicity, detection, detoxification, and dietary prophylaxis

Ochratoxin A (OTA) is a toxic metabolite produced by Aspergillus and Penicillium fungi commonly found in raw plant sources and other feeds. This review comprises an extensive evaluation of the origin and proprieties of OTA, toxicokinetics, biotransformation, and toxicodynamics of ochratoxins. In in vitro and in vivo studies, the compatibility of OTA with oxidative stress is observed through the production of free radicals, resulting in genotoxicity and carcinogenicity. The OTA leads to nephrotoxicity as the chief target organ is the kidney. Other OTA excretion and absorption rates are observed, and the routes of elimination include faeces, urine, and breast milk. The alternations in the Phe moiety of OTA are the precursor for the amino acid alternation, bringing about Phe-hydroxylase and Phe-tRNA synthase, resulting in the complete dysfunction of cellular metabolism. Biodetoxification using specific microorganisms decreased the DNA damage, lipid peroxidation, and cytotoxicity. This review addressed the ability of antioxidants and the dietary components as prophylactic measures to encounter toxicity and demonstrated their capability to counteract the chronic exposure through supplementation as feed additives.