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BACKGROUND: Fresh milk and natural environmental conditions are used to produce traditional cheeses. Such cheeses are produced by dozens of different types of microbes. Non-starter lactobacilli are the most responsible genus of lactic acid bacteria exhibiting key technological and health promoting traits. The purpose of this study is to isolate Lactobacillus bacteria from conventional Egyptian cheeses and analyse their probiotic potential and technological properties. RESULTS: Lactobacillus isolates (33 isolates) were isolated from different Egyptian cheeses. Our results revealed that 18.18% of the isolates were fast-acidifying, 30.3% were medium-acidifying and 51.5% were slow-acidifying isolates. The results of autolytic activity showed that 24.3% of the isolates were good autolysis, 33.3% were fair autolysis, while 42.4% were poor autolysis. Fifteen isolates produced exopolysaccharides, while 9 isolates exhibited antimicrobial activities against Lactobacillus bulgaricus 340. All the isolates were resistant to pH 3 for 3 h except isolate No. 15 (MR4). The growth rate of the isolates ranged from 42.25 to 85.25% at 0.3% bile salts after 3 h of incubation. The surviving percentage of the Lactobacillus isolates decreased with increasing incubation time or the percentage of bile salts greater than 0.3%. All the isolates grew after incubation in artificial gastric and intestinal fluids. The auto-aggregation of 15 isolates ranged from 43.13 to 72.77%. Lacticaseibacillus paracasei BD3, Lactiplantibacillus plantarum BR4 and Limosilactobacillus fermentum MR2 were sensitive to the majority of the tested antibiotics and showed good bile salt hydrolase activity. CONCLUSION: L. paracasei BD3, L. plantarum BR4 and L. fermentum MR2 were isolated from Egyptian cheeses and showed probiotic and technological characterization, which are valuable for their practical application as starters, adjunct and protective cultures in cheese making.
Assuntos
Queijo , Probióticos , Lactobacillus , Egito , Queijo/microbiologia , Ácidos e Sais Biliares/farmacologiaRESUMO
Dietary selenium (Se) sources affects the structure of the rumen microbial community and rumen fermentation. This study evaluated the effects of sodium selenite (SS) and bio-nanostructured selenium (SeNSM) on rumen fermentation and structure of rumen microbial community of lactating Barki ewes. Twenty one lactating Barki ewes were assigned into three groups based on their body weight and milk yield. The experiment lasted for 50 days, whenever, the control group was fed basal diet; group SS received basal diets plus sodium selenite as inorganic source of Se; and group SeNSM received basal diet plus organic selenium bio-nanostructured. Ruminal pH and volatile Fatty Acids (VFA) was lower (P < 0.05) in SeNSM group compared to control. Principle Coordinate Analysis separated the microbial communities into three clusters based on feeding treatment. The bacterial community was dominated by phylum Bacteroidetes and Firmicutes that were affected (P < 0.05) by Se sources. Specifically Bacteriodetes was higher (P < 0.05) in SS and SeNSM groups; and Firmicutes was higher (P < 0.05) in the control group. Moreover, the predominant bacterial genera were Prevotella, Rikenellaceae RC9 gut group, Unclassified_Bacteroidales, which were higher (P < 0.05) in SeNSM group. The methanogenic community belonged to phylum Euryarchaeota and was significantly decreased (P < 0.05) by Se supplementation. Principal component analysis based on rumen fermentation parameters, and relative abundances of bacteria and methanogens revealed three distinct clusters. These findings suggest that Se supplementation affected the relative abundances of dominant bacterial groups, declined rumen methanogens and SeNSM supplementation showed some positive impacts on some fibrolytic bacteria.
Assuntos
Microbiota , Selênio , Ovinos , Animais , Feminino , Selenito de Sódio/farmacologia , Suplementos Nutricionais/análise , Selênio/farmacologia , Selênio/metabolismo , Rúmen/metabolismo , Lactação , Fermentação , Dieta/veterinária , Bactérias , FirmicutesRESUMO
Aflatoxin B1 (AFB1) is a plant-origin toxin that could induce oxidative stress in fish. The micromineral selenium (Se) possesses well-documented antioxidant properties. To assess the ameliorative effects of SeNPs (1 mg/kg fish feed) on oxidative stress induced by AFB1 (500 µg/kg fish feed), Nile tilapia (32.2±1.7 g body weight) were distributed randomly and even in six groups for 8-week feeding trial. Live enzymes, AST, ALT, and ALP levels were increased in the serum of fish fed AFB1-contaminated diet, and the addition of SeNPs could restore normal values compared to the control. The gene expression of antioxidant enzymes, superoxide dismutase (SOD) enzyme and catalase (CAT) enzyme, and DNA fragmentation were significantly increased in response to aflatoxin exposure, while dietary SeNPs could mitigate the generated oxidative stress. The innate immunity, serum antibacterial activity (SAA), oxidative burst activity (OBA), phagocytic activities (PA and PI), and gene expression of cytokines (interleukin (IL)-1ß, heat shock protein70 (Hsp), and tumor necrosis factor (TNF)-α) revealed a status of immunosuppression in Nile tilapia fed on AFB1-contaminated diet. These findings showed that fish became more vulnerable to Streptococcus agalactiae infection with a high mortality rate while dietary SeNPs provided a high relative protection level (RPL). From the obtained findings, SeNPs could mitigate the oxidative stress induced by feeding the AFB1 diet and could boost the immunity of stressed Nile tilapia.
RESUMO
Imidacloprid is an insecticide that protects against insects in the agriculture, animal, and poultry production sectors. Since the accumulation of imidacloprid induces adverse impacts on general health status and quality of the food chain, this study tested the impacts on broilers. Besides, selenium nanoparticles were fed to birds to relieve the negative impacts on growth performance and health status. Birds (1-day age, initial weight 46.05 ± 1.0 g) divided into four groups (triplicates) where 15 chicks of each replicate (45 for each group). The first group (control) was fed the basal diet without either selenium or imidacloprid toxicity. The second group was fed selenium nano form at 3 mg/kg. The third group was fed selenium and exposed to imidacloprid at 1/10 LT50 (3 mg/kg body weight). The fourth group was fed selenium nano form (3 mg/kg) and exposed to imidacloprid at 1/10 LT50 (3 mg/kg body weight). All groups were kept under the same conditions for 35 days. The final weight and weight gain of birds fed selenium nano form showed marked improvement compared to the imidacloprid-exposed group, while the feed intake and feed conversion ratio markedly reduced. The red blood cells showed higher values in birds fed selenium nano than the control and those exposed to imidacloprid. Interestingly, the hemoglobulin and hematocrit increased in birds fed selenium nano form with or without imidacloprid exposure. Furthermore, the white blood cells increased in birds fed selenium nano form with or without imidacloprid exposure. The total protein, albumin, and globulin were higher in birds fed selenium nanoparticles than those exposed to imidacloprid with or without selenium feeding. Birds in the control and imidacloprid groups had higher aspartate aminotransferase (AST), alanine aminotransferase (ALT), and malondialdehyde levels than the remaining groups. Accordingly, dietary selenium nanoparticles are suggested in broiler feed to cope with the adverse effects of imidacloprid toxicity.
Assuntos
Nanopartículas , Selênio , Animais , Selênio/farmacologia , Selênio/metabolismo , Galinhas/metabolismo , Suplementos Nutricionais , Aves Domésticas , Peroxidação de Lipídeos , Dieta/veterinária , Aumento de Peso , Ração Animal/análiseRESUMO
Supplementation of selenium in poultry feed is required in an optimum dose and form for optimizing the growth performance and health status. Selenium nanospheres are suggested as an efficient and alternative to the conventional organic or inorganic forms. The study evaluated the effects of selenium (Se) nanospheres (SeNPs) as an alternative to organic Se (Sel-Plex®) or inorganic Se (sodium selenite, Se(IV Se(IV)) on the growth performance, carcass traits, blood biochemistry, and antioxidative capacity in turkey pullets. A total of 160 1-day-old Bronze turkey poults chicks were divided into four groups with 40 pullets each. The birds were fed on four types of diets as fellow: control (basal diet, 0.01 Se mg/kg), SeNPs (0.43 Se mg/kg), organic Se Sel-Plex® (0.41 Se mg/kg), and inorganic Se(IV) (0.42 Se mg/kg) for 8 weeks. No changes were seen in the body weight gain in growing turkey pullet, but chicks fed with Sel-Plex® form recorded the lowest feed intake (p < 0.05) compared to other treatments. Dietary SeNPs and Se(IV) selenium sources improved the feed conversion ratio compared to other treatments. All Se forms fed on turkey pullets showed higher carcass percentage weight and liver Se content than the control group. However, the gizzard percentage weight in the SeNPs group was lower than in the other treatments (p < 0.05). Birds fed SeNPs, and Sel-Plex® forms supplemental diets had a lower cholesterol concentration (p < 0.05) than the control and Se(IV). While high-density lipoprotein (HDL) concentration was increased in SeNPs and Se(IV) groups, and total protein concentration was higher in the Se(IV) group. Furthermore, dietary SeNPs reduced (p < 0.05) the low-density lipoprotein (LDL), total lipids, triglycerides, alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatine, uric acid, urea, and malondialdehyde plasma concentrations and increased the glutathione peroxidase activity (GPx) and total antioxidative capacity (TAC). In conclusion, the results confirmed that feeding turkey pullets on SeNPs form with the 0.4 Se mg/kg of feed enhanced feed efficiency, growth performance, carcass traits, plasma lipids concentration, and antioxidative capacity.
Assuntos
Nanosferas , Selênio , Ração Animal/análise , Animais , Antioxidantes/farmacologia , Galinhas/metabolismo , Dieta/veterinária , Suplementos Nutricionais , Feminino , Lipídeos , Selenito de Sódio/farmacologia , PerusRESUMO
The present study was conducted to investigate the effects of nano-selenium (Nano Se) or/and vitamin E (VE) on growth performance, blood health, intestinal histomorphology, oxidative status, and immune-related gene expression of Nile tilapia. Nano Se or/and VE at a rate of 0, 1 mg Nano Se/kg, 100 mg VE/kg, and 1 mg Nano Se/kg + 100 mg VE diet were fed to fish for 8 weeks. FBW was significantly (P < 0.05) increased in fish fed with Nano Se and VE, while fish fed with Nano Se or Nano Se and VE diets displayed significantly (P < 0.05) higher WG and SGR than the other groups. The lowest FCR was significantly (P < 0.05) detected in fish fed with Nano Se and VE, while the highest value was observed in fish VE diet. The intestinal morphometry (villi length and width) of fish fed with Nano Se or/and VE reported significantly (P < 0.05) the highest values with high number of goblet cells. Blood hematology and biochemistry parameters of fish fed with Nano Se or/and VE showed normal values with insignificant differences except for the blood total protein increased in fish fed with Nano Se or/and VE (P < 0.05). Dietary Nano Se or Nano Se and VE significantly (P < 0.05) increased the GPX, SOD, CAT, NBT, lysozyme, and phagocytosis values with decreased MDA. Liver and spleen TNF-α and IL-1ß expressions were significantly (P < 0.05) upregulated in fish fed on Nano Se or Nano Se and VE. Thus, Nano Se or/and VE can be used effectively in tilapia diets for improving the growth, intestinal health, blood health, oxidative status, and immune-related gene expression.
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Antioxidantes/metabolismo , Nanopartículas/química , Selênio/farmacologia , Vitamina E/farmacologia , Animais , Ciclídeos/crescimento & desenvolvimento , Ciclídeos/imunologia , Ciclídeos/metabolismo , Dieta , Perfilação da Expressão Gênica , Nanopartículas/administração & dosagem , RNA/genética , RNA/isolamento & purificação , Selênio/administração & dosagem , Selênio/química , Vitamina E/administração & dosagem , Vitamina E/química , Aumento de Peso/efeitos dos fármacosRESUMO
Functional trace elements and vitamins can boost immunity and antioxidative response in aquatic animals without creating environmental hazards. While nano-selenium (Nano-Se) and vitamin C (VC) have been used as immunomodulators and antioxidants in animal and poultry feed, there is little data on Nano-Se and/or VC supplementation in aquatic animals. Thus, the current study evaluated the impact of adding Nano-Se and VC to the diets of Nile tilapia for 8 weeks. Four diets were formulated and offered to the fish: no supplementation (control), 1 mg Nano-Se/kg, 500 mg VC/kg, and 1 mg Nano-Se + 500 mg VC/kg of food. Growth-related parameters (final body weight, weight gain, and specific growth rate) were significantly increased in tilapia fed Nano-Se and VC, with a reduced feed conversion ratio (P < 0.05). Intestinal villus length and width as well as the number of goblet cells were increased in tilapia fed Nano-Se and/or VC (P < 0.05). Additionally, dietary Nano-Se and/or VC significantly increased nitro-blue tetrazolium (NBT) level, superoxide dismutase, glutathione peroxidase, catalase, the phagocytic index, and lysozyme and phagocytic activities (P < 0.05). However, significantly reduced levels of malonaldehyde were observed in fish fed Nano-Se and/or VC (P < 0.05). TNF-α and IL-1ß gene expressions in the liver and spleen of the fish were significantly upregulated by Nano-Se and/or VC (P < 0.05). The results revealed the potential role of Nano-Se and/or VC in enhancing growth, intestinal morphometry, and immune and antioxidative responses in Nile tilapia.
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Ciclídeos , Doenças dos Peixes , Selênio , Ração Animal/análise , Animais , Ácido Ascórbico , Dieta , Suplementos Nutricionais , VitaminasRESUMO
BACKGROUND/AIMS: Bovine milk whey, which mainly includes beta-lactoglobulin (58%), alpha-lactalbumin (22%) and immunoglobulin G (IgG; 11%), is a source of a wide range of proteins with a useful nutritional and physiological function. We previously demonstrated antiperoxidative effects of whey-derived alpha-lactalbumin and beta-lactoglobulin in rats. The aim of the present study was to investigate the role of the IgG in antiperoxidative properties. METHODS: Four-week-old, male Sprague-Dawley rats were fed a vitamin E-deficient diet (control) or a diet supplemented with 2.5% of an IgG-rich fraction for 4 weeks. Different antiperoxidative parameters were measured in blood and liver from the rats. RESULTS: In comparison to the rats fed the control diet, those fed the IgG-containing diet were resistant to peroxidation stress. The IgG diet resulted in a decreased concentration of thiobarbituric acid-reactive substances in red blood cells (RBC) and plasma, and increased activities of catalase, superoxide dismutase and glutathione peroxidase in the RBC and liver. The plasma density (d) < 1.063 g/ml lipoproteins from the IgG group were more resistant against the induced lipid peroxidation. CONCLUSION: These results demonstrate antiperoxidative properties of IgG. The underlying mechanism(s) remain to be determined.