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This study delves into the transformative effects of supercritical carbon dioxide (scCO2) cannabis extracts and prebiotic substances (dextran, inulin, trehalose) on gut bacteria, coupled with a focus on neuroprotection. Extracts derived from the Bialobrzeska variety of Cannabis sativa, utilising supercritical fluid extraction (SFE), resulted in notable cannabinoid concentrations (cannabidiol (CBD): 6.675 ± 0.166; tetrahydrocannabinol (THC): 0.180 ± 0.006; cannabigerol (CBG): 0.434 ± 0.014; cannabichromene (CBC): 0.490 ± 0.017; cannabinol (CBN): 1.696 ± 0.047 mg/gD). The assessment encompassed antioxidant activity via four in vitro assays and neuroprotective effects against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). The extract boasting the highest cannabinoid content exhibited remarkable antioxidant potential and significant inhibitory activity against both enzymes. Further investigation into prebiotic deliveries revealed their proficiency in fostering the growth of beneficial gut bacteria while maintaining antioxidant and neuroprotective functionalities. This study sheds light on the active compounds present in the Bialobrzeska variety, showcasing their therapeutic potential within prebiotic systems. Notably, the antioxidant, neuroprotective, and prebiotic properties observed underscore the promising therapeutic applications of these extracts. The results offer valuable insights for potential interventions in antioxidant, neuroprotective, and prebiotic domains. In addition, subsequent analyses of cannabinoid concentrations post-cultivation revealed nuanced changes, emphasising the need for further exploration into the dynamic interactions between cannabinoids and the gut microbiota.
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Antioxidantes , Cannabis , Fármacos Neuroprotetores , Extratos Vegetais , Prebióticos , Cannabis/química , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antioxidantes/farmacologia , Antioxidantes/química , Canabinoides/química , Canabinoides/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Acetilcolinesterase/metabolismo , Butirilcolinesterase/metabolismoRESUMO
This study investigates the suitability of using caffeine-treated and untreated black cherry (Prunus serotina Ehrh.) wood as a polylactide filler. Composites containing 10%, 20%, and 30% filler were investigated in terms of increasing the nucleating ability of polylactide, as well as enhancing its resistance to microorganisms. Differential scanning calorimetry studies showed that the addition of caffeine-treated wood significantly altered the crystallization behavior of the polymer matrix, increasing its crystallization temperature and degree of crystallinity. Polarized light microscopic observations revealed that only the caffeine-treated wood induced the formation of transcrystalline structures in the polylactide. Incorporation of the modified filler into the matrix was also responsible for changes in the thermal stability and decreased hydrophilicity of the material. Most importantly, the use of black cherry wood treated with caffeine imparted antifungal properties to the polylactide-based composite, effectively reducing growth of Fusarium oxysporum, Fusarium culmorum, Alternaria alternata, and Trichoderma viride. For the first time, it was reported that treatment of wood with a caffeine compound of natural origin alters the supermolecular structure, nucleating abilities, and imparts antifungal properties of polylactide/wood composites, providing promising insights into the structure-properties relationship of such composites.
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This study investigates the potential of formulated systems utilising haskap berry leaf extracts and dextran as carriers, to modulate both antioxidant and enzymatic inhibitory activities and their impact on the growth of specific bacterial strains. The analysis of antioxidant capacity, assessed through ABTS, CUPRAC, DPPH, and FRAP assays, revealed varying but consistently high levels across extracts, with Extract 3 (loganic acid: 2.974 mg/g, chlorogenic acid: 1.125 mg/g, caffeic acid: 0.083 mg/g, rutin: 1.137 mg/g, and quercetin: 1.501 mg/g) exhibiting the highest values (ABTS: 0.2447 mg/mL, CUPRAC: 0.3121 mg/mL, DPPH: 0.21001 mg/mL, and FRAP: 0.3411 mg/mL). Subsequent enzymatic inhibition assays demonstrated a notable inhibitory potential against α-glucosidase (1.4915 mg/mL, expressed as acarbose equivalent), hyaluronidase (0.2982 mg/mL, expressed as quercetin equivalent), and lipase (5.8715 µg/mL, expressed as orlistat equivalent). Further system development involved integration with dextran, showcasing their preserved bioactive compound content and emphasising their stability and potential bioactivity. Evaluation of the dextran systems' impact on bacterial growth revealed a significant proliferation of beneficial strains, particularly the Bifidobacterium and lactobacilli genus (Bifidobacterium longum: 9.54 × 107 to 1.57 × 1010 CFU/mL and Ligilactobacillus salivarius: 1.36 × 109 to 1.62 × 1010 CFU/mL), suggesting their potential to modulate gut microbiota. These findings offer a foundation for exploring the therapeutic applications of haskap berry-based dextran systems in managing conditions like diabetes, emphasising the interconnected roles of antioxidant-rich botanical extracts and dextran formulations in promoting overall metabolic health.
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Adhesion is one of the main factors responsible for the probiotic properties of bacteria in the human gut. Membrane proteins affected by cellular damage are one of the key aspects determining adhesion. Fluid-bed-dried preparations containing probiotic bacteria were analyzed in terms of their stability (temperature of glass transition) and shelf life in different conditions (modified atmosphere, refrigeration). Imaging flow cytometry was utilized to determine four subpopulations of cells based on their physiological and morphological properties. Lastly, adhesion was measured in bacteria cultured in optimal conditions and treated with heat shock. The results show that the subpopulations with no or low levels of cell membrane damage exhibit the ability to adhere to Caco-2 cells. The temperature of protein denaturation in bacteria was recorded as being between 65 °C and 70 °C. The highest glass transition temperature (Tg) value for hydroxypropyl methylcellulose (used as a coating substance) was measured at 152.6 °C. Drying and coating can be utilized as a sufficient treatment, allowing a long shelf-life (up to 12 months). It is, however, worth noting that technological processing, especially with high temperatures, may decrease the probiotic value of the preparation by damaging the bacterial cells.
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Bactérias , Probióticos , Humanos , Viabilidade Microbiana , Células CACO-2 , Membrana CelularRESUMO
Hesperidin is a polyphenol derived from citrus fruits that has a broad potential for biological activity and the ability to positively modify the intestinal microbiome. However, its activity is limited by its low solubility and, thus, its bioavailability-this research aimed to develop a zein-based hesperidin system with increased solubility and a sustained release profile. The study used triple systems enriched with solubilizers to maximize solubility. The best system was the triple system hesperidin-zein-Hpß-CD, for which the solubility improved by more than six times. A significant improvement in the antioxidant activity and the ability to inhibit α-glucosidase was also demonstrated, due to an improved solubility. A release profile analysis was performed in the subsequent part of the experiments, confirming the sustained release profile of hesperidin, while improving the solubility. Moreover, the ability of selected probiotic bacteria to metabolize hesperidin and the effect of this flavonoid compound on their growth were investigated.
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Citrus , Hesperidina , Zeína , Hesperidina/farmacologia , Prebióticos , Preparações de Ação Retardada , ExcipientesRESUMO
Chitosan is a natural and biodegradable polymer with promising potential for biomedical applications. This study concerns the production of chitosan-based materials for future use in the medical industry. Bioactive substances-caffeine and ethanolic propolis extract (EEP)-were incorporated into a chitosan matrix to increase the bioactivity of the obtained films and improve their mechanical properties. Acetic and citric acids were used as solvents in the production of the chitosan-based films. The obtained materials were characterized in terms of their antibacterial and antifungal activities, as well as their mechanical properties, including tensile strength and elongation at break. Moreover, the chemical structures and surface morphologies of the films were assessed. The results showed that the solution consisting of chitosan, citric acid, caffeine, and EEP exhibited an excellent antiradical effect. The activity of this solution (99.13%) was comparable to that of the standard antioxidant Trolox (92.82%). In addition, the film obtained from this solution showed good antibacterial activity, mainly against Escherichia coli and Enterococcus faecalis. The results also revealed that the films produced with citric acid exhibited higher activity levels against pathogenic bacteria than the films obtained with acetic acid. The antimicrobial effect of the chitosan-based films could be further enhanced by adding bioactive additives such as caffeine and propolis extract. The mechanical tests showed that the solvents and additives used affected the mechanical properties of the films obtained. The film produced from chitosan and acetic acid was characterized by the highest tensile strength value (46.95 MPa) while the chitosan-based film with citric acid showed the lowest value (2.28 MPa). The addition of caffeine and propolis to the film based on chitosan with acetic acid decreased its tensile strength while in the case of the chitosan-based film with citric acid, an increase in strength was observed. The obtained results suggested that chitosan films with natural bioactive substances can be a promising alternative to the traditional materials used in the medical industry, for example, as including biodegradable wound dressings or probiotic encapsulation materials.
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Fisetin (FIS), a senolytic flavonoid, mitigates age-related neuroprotective changes. An amorphous FIS dispersion with a co-carrier was prepared using supercritical fluid extraction with carbon dioxide (scCO2). Characterisation, including powder X-ray diffraction and Fourier-transform infrared spectroscopy, confirmed amorphization and assessed intermolecular interactions. The amorphous FIS dispersion exhibited enhanced solubility, dissolution profiles, and bioavailability compared to the crystalline form. In vitro, the amorphous FIS dispersion demonstrated antioxidant activity (the ABTS, CUPRAC, DDPH, FRAP assays) and neuroprotective effects by inhibiting acetylcholinesterase and butyrylcholinesterase. FIS modulated gut microbiota, reducing potentially pathogenic gram-negative bacteria without affecting probiotic microflora. These improvements in solubility, antioxidant and neuroprotective activities, and gut microbiome modulation suggest the potential for optimising FIS delivery systems to leverage its health-promoting properties while addressing oral functionality limitations.
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The presented research evaluates the medical use potential of Lonicera caerulea leaves, which are waste plants in cultivating berries. The study's screening activity included the leaves of five varieties of Lonicera caerulea: Atut, Duet, Wojtek, Zojka, and Jugana. The microbiological analysis confirmed the safety of using Lonicera caerulea leaves without significant stabilization. Lonicera caerulea leaves standardization was carried out based on the results of the chromatographic analysis, and it showed differences in the contents of active compounds (loganic, chlorogenic and caffeic acids, and rutin), which are attributed to biological activity. For the Lonicera caerulea leaves varieties tested, the differences in the content of total polyphenol content, chlorophylls, and carotenoids were also confirmed. The screening of biological activity of five Lonicera caerulea leaf varieties was carried out concerning the possibility of inhibiting the activity of α-glucosidase, lipase, and hyaluronidase as well, and the antioxidant potential was determined. The defined profile of the biological activity of Lonicera caerulea leaves makes it possible to indicate this raw material as an essential material supporting the prevention and treatment of type II diabetes. However, this research showed that tested enzymes were strongly inhibited by the variety Jugana. The health-promoting potential of Lonicera caerulea leaves was correlated with the highest chlorogenic acid and rutin content in the variety Jugana.
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Diabetes Mellitus Tipo 2 , Lonicera , Antioxidantes/análise , Antioxidantes/farmacologia , Ácidos Cafeicos/análise , Carotenoides/análise , Carotenoides/farmacologia , Ácido Clorogênico/análise , Ácido Clorogênico/farmacologia , Frutas/química , Hialuronoglucosaminidase/análise , Lipase , Lonicera/química , Folhas de Planta/química , Polifenóis/análise , Polifenóis/farmacologia , Rutina/análise , Rutina/farmacologia , alfa-GlucosidasesRESUMO
Propolis is one of the bee products, with multiple biological properties used in numerous applications. The research objective was to determine the chemical composition and biological properties (antibacterial, antifungal, antiviral, antioxidant, and cytoprotective activity) of propolis extracts collected from various regions of Poland. The results indicated that the total content of phenols (116.16-219.41 mg GAE/g EEP) and flavonoids (29.63-106.07 mg QE/g EEP) in propolis extracts depended on their geographic origin. The high content of epicatechin, catechin, pinobanksin, myricetin, and acids: vanillic and syringic in propolis samples was confirmed by chromatographic analysis. Moreover, the presence of caffeic acid phenethyl ester was confirmed in all samples. The origin of propolis also influenced the biological properties of its extracts. The propolis extracts were characterized by moderate DPPH free radical scavenging activity (29.22-35.14%), and relatively low ferrous iron chelating activity (9.33-32.32%). The results indicated also that the propolis extracts showed high activity in the protection of human red blood cells against free radicals generated from 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AAPH). The extracts exhibited diversified activity against the tested pathogenic bacteria and limited activity against fungal strains. The research of selected propolis extracts showed that only 2 of 5 examined samples showed moderate activity against HPV (human papillomaviruses) and the activity depended on its geographical distribution.
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Catequina , Própole , Humanos , Própole/farmacologia , Própole/química , Polônia , Antioxidantes/farmacologia , Antioxidantes/química , Fenóis/química , Antibacterianos , Flavonoides/químicaRESUMO
The aim of the research was to determine the influence of chitosan type and propolis extract concentration on biological and physicochemical properties of chitosan-propolis films in terms of their applicability in food packaging. The films were prepared using three types of chitosan: from crab shells, medium and high molecular weight and propolis concentration in the range of 0.75-5.0%. The prepared polysaccharide films were tested for antimicrobial properties, oxygen transmission rate (OTR) and water vapor transmission rate (WVTR). Moreover, sorption tests and structural analysis were carried out. Microbiological tests indicated the best antimicrobial activity for the film consisting of high molecular weight chitosan and 5.0% propolis extract. Both the type of chitosan and propolis concentration affected transmission parameters-OTR and WVTR. The best barrier properties were recorded for the film composed of high molecular weight chitosan and 5.0% propolis extract. The results of sorption experiments showed a slight influence of chitosan type and a significant effect of propolis extract concentration on equilibrium moisture content of tested films. Moreover, propolis extract concentration affected monolayer water capacity (Mm) estimated using the Guggenheim, Anderson and de Boer (GAB) sorption model. The obtained results indicate that chitosan films with an addition of propolis extract are promising materials for food packaging applications, including food containing probiotic microorganisms.
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Listeria monocytogenes is a foodborne pathogen, sporadically present in various food product groups. An illness caused by the pathogen, named listeriosis, has high fatality rates. Even though L. monocytogenes is resistant to many environmental factors, e.g., low temperatures, low pH and high salinity, it is susceptible to various natural plant-derived antimicrobials (NPDA), including thymol, carvacrol, eugenol, trans-cinnamaldehyde, carvone S, linalool, citral, (E)-2-hexenal and many others. This review focuses on identifying NPDAs active against L. monocytogenes and their mechanisms of action against the pathogen, as well as on studies that showed antimicrobial action of the compounds against the pathogen in food model systems. Synergistic action of NDPA with other factors, biofilm inhibition and alternative delivery systems (encapsulation and active films) of the compounds tested against L. monocytogenes are also summarized briefly.
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Providing safe products and compliance of legal requirements is still a great challenge for food manufacturers regarding microbiological safety, especially in the context of Listeria monocytogenes food contamination. L. monocytogenes is a human pathogen, which, due to the ability of survival and proliferation in preservation conditions such as high salinity, acidity and refrigeration temperatures, is a significant threat to the food industry. Novel methods of elimination of the bacterial pathogen in food products and food processing environments are required. Among emerging technologies, one of the very promising solutions is using bacteriophages as natural control agents. This review focus on the major aspects of phage-based inhibition of L. monocytogenes in aspects of food safety. We describe an overview of foods and technological factors influencing the efficacy of phage use in biocontrol of L. monocytogenes. The most noteworthy are food matrix properties, phage concentration and stability, the time of phage application and product storage temperature. The combined methods, phage immobilization (active packing), pathogen resistance to phages and legislation aspects of antilisterial bacteriophage use in the food industry are also discussed.
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The feed supplementation of probiotic microorganisms is a promising method for detoxification of ochratoxin A (OTA) in poultry. The aim of the study was to investigate the effect of newly elaborated synbiotics on the turkey performance, the intestinal microbiota and its enzymatic activity in turkeys (0-15 weeks) fed OTA contaminated feed (198.6-462.0 µg/kg) compared to control group (OTA-free feed). The studies determined the composition of intestinal microorganisms by the culture method and the activity of fecal enzymes by spectrophotometry. It was found that OTA had an adverse effect on the body weight, the intestinal microbiota and the fecal enzymes activity in turkeys. On the other hand, synbiotics resulted in an increase in the count of beneficial bacteria while reducing the number of potential pathogens in the digestive tract. Moreover, synbiotics caused an increase in the activity of α-glucosidase and α-galactosidase, while decreasing the activity of potentially harmful fecal enzymes (ß-glucosidase, ß-galactosidase, ß-glucuronidase) in the turkey's excreta. Results indicate a beneficial effect of elaborated synbiotics on the health of turkeys and a reduction of the negative impact of OTA contaminated feed. These synbiotics can be successfully used as feed additives for turkeys.
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Ração Animal/microbiologia , Bactérias/crescimento & desenvolvimento , Microbioma Gastrointestinal , Ocratoxinas/toxicidade , Simbióticos , Perus/microbiologia , Criação de Animais Domésticos , Fenômenos Fisiológicos da Nutrição Animal , Animais , Composição Corporal , Fezes/enzimologia , Fezes/microbiologia , Estado Nutricional , Valor Nutritivo , Ocratoxinas/metabolismo , Perus/crescimento & desenvolvimento , Perus/metabolismo , Aumento de PesoRESUMO
In order to assess the essential probiotic properties of a strain dedicated for administration in humans and animals, characteristics of finally formulated products, rather than the cells solely, seems to be of crucial importance. In this study, composition of protective blends for manufacture of L. lactis probiotic powders was optimized using a statistical experimental design. The powders, generated by either spray- or freeze-drying techniques, were subsequently subjected to storage testing, and in vitro digestion in simulated stomach and small intestine. Finally, maintenance of adherence capability to human enterocyte-like cell lines, was evaluated. Our data demonstrated that 10% trehalose ensures the highest viability of L. lactis bacteria upon both drying techniques (viability of 60-68%). Moreover, skimmed milk-protected spray-dried cells exhibit the highest resistance to harsh environmental conditions of stomach (53.9⯱â¯7.6% survival rate) and higher adhesion ability to HT-29 cell line after digestion (528⯱â¯29 cells per 100 epithelial cells).
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Lactococcus lactis/efeitos dos fármacos , Preservação Biológica/métodos , Probióticos/farmacologia , Animais , Aderência Bacteriana/efeitos dos fármacos , Liofilização , Células HT29 , Humanos , Lactococcus lactis/metabolismo , Lactococcus lactis/fisiologia , Viabilidade Microbiana/efeitos dos fármacos , Trealose/farmacologiaRESUMO
The aim of this study was to compare the effect of probiotic bacteria, prebiotics, phytobiotics and their combinations on performance and microbial activity in the digestive tract of growing pigs. The experiment was conducted over 28 d on 48 male pigs of about 12 kg body weight (BW), which were allocated to following treatments.: (1) Control Group (Con) without additive, (2) Group I, addition of a prebiotic (inulin), (3) Group Ph, a phytobiotic (herbal water extracts), (4) Group P, a probiotic composed of four strains of lactic acid bacteria, (5) Group PhP, phytobiotic and probiotic bacteria and (6) Group PhPI, a phytobiotic, probiotic bacteria and a prebiotic. Animal performance was recorded and at d 28 six pigs from each group were euthanised to collect digesta samples. In all groups except for Group I, diarrhoea incidents were observed. Groups Ph and P had significantly higher daily gains and final BW, and Group Ph utilised feed better than other groups. The pH of ileal digesta was significantly lower in Group PhPI. In the caecal digesta of Groups I, P and PhP, the pH level was lower than in the other groups but dry matter contents was significantly higher in Groups Con and I. The short-chain fatty acids and particular acid content differed significantly only in the colonic digesta. The yeast and mould numbers in caecal digesta was highest in Group Con. No treatment effects were observed for the number of lactic acid bacteria, coli group bacteria or Clostridium. However, the observed significantly higher number of total bacteria suggests that a multi-component eubiotic treatment changes the bacterial composition and distribution more effectively. Our findings indicated that all used additives changed the intestinal microflora, but the multi-component eubiotics were not beneficial as feed additives offered separately. Moreover, supplementation of phytobiotics and probiotic bacteria also improved the animal performance significantly.
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Trato Gastrointestinal/microbiologia , Prebióticos , Probióticos/farmacologia , Sus scrofa/crescimento & desenvolvimento , Sus scrofa/microbiologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Carnobacterium/química , Dieta/veterinária , Enterococcus faecium/química , Leuconostoc mesenteroides/química , Masculino , Origanum/química , Prebióticos/administração & dosagem , Probióticos/administração & dosagem , Thymus (Planta)/químicaRESUMO
Plant non-specific lipid transfer proteins (nsLTPs) are small basic proteins, which mostly play a role in intracellular lipid transport and antimicrobial defense. Recently it was shown using shotgun proteomic approach that the whole plant extract of Chelidonium majus L. (Papaveraceae) contains relatively abundant nsLTPs. Therefore the aim of the work was to isolate and characterize nsLTP from C. majus latex. Results obtained using PCR approach with degenerate primers showed the presence of nsLTP protein in C. majus root latex, named CmLTP 9.5. The protein consists of 93 aa with a molecular weight of 9.5kDa (NCBI GenBank accession no. ALT21495, coded by KP733898). The mature form of CmLTP 9.5 has a molecular weight of 7.147kDa and contains typical eight strictly conserved cysteine residues. A 3D model of CmLTP 9.5 displays a hydrophobic cavity. The isolated protein fraction tested using diffusion method and critical dilution assay showed strong antibacterial activity towards Gram-negative Campylobacter jejuni as well as Gram-positive Listeria greyi and Clostridium perfringens. Further studies using protein expression system are required to fully understand CmLTP 9.5 mode of action.
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Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Proteínas de Transporte/isolamento & purificação , Proteínas de Transporte/farmacologia , Chelidonium/química , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/farmacologia , Sequência de Aminoácidos , Antibacterianos/química , Bactérias/efeitos dos fármacos , Proteínas de Transporte/química , Modelos Moleculares , Filogenia , Proteínas de Plantas/química , Domínios ProteicosRESUMO
The aim of this study was to determine the degree of adhesion and hydrophobicity of some strains of lactic acid bacteria (LAB) with proven antagonistic properties against pathogenic bacteria. Studies were performed using-LAB strains isolated from the gastrointestinal tract of calves and piglets. These strains exhibited an antibacterial activity against pathogenic strains of Clostridium perfringens and Escherichia coli. Cell adhesiveness was examined in relation to the porcine and bovine mucin. Our analyses had shown that the tested microorganisms demonstrated a degree of adhesion in the range of 32.00-40.00% for strains isolated from calves, and 34.00-40.00% for strains isolated from pigs. The hydrophobicity of tested bacteria was in the range of 31.00%-44.00% for strains isolated from pigs, and 26.00%-42.00% for strains obtained from calves. The best mucin adhesion ability was found for bacterial strains belonging to the Enterococcus genus isolated from calves. Taking into account porcine isolates, the best adhesion was observed for the Leuconostoc bacterial strains. Among tested strains, the highest hydrophobicity, measured in relation to hexadecane, was recorded for the bacterial strains belonging to the Leuconostoc sp. isolated from piglets and a of Lactobacillus sp. bacterial strain isolated from calves.
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Lactobacillus/fisiologia , Animais , Antibiose , Aderência Bacteriana , Clostridium perfringens/fisiologia , Escherichia coli/fisiologia , Trato Gastrointestinal/microbiologia , Interações Hidrofóbicas e Hidrofílicas , Lactobacillus/isolamento & purificação , Viabilidade Microbiana , Mucinas/química , Sus scrofa/microbiologiaRESUMO
The filamentous fungus Myrothecium roridum isolated from a dye-contaminated area was investigated in terms of its use for the treatment of Malachite green (MG). The mechanisms involved in this process were established. Peroxidases and cytochrome P-450 do not mediate MG elimination. The laccase of M. roridum IM 6482 was found to be responsible for the decolorization of 8-11% of MG. Thermostable low-molecular-weight factors (LMWF) resistant to sodium azide were found to be largely involved in dye decomposition. In addition, MG decolorization by M. roridum IM 6482 occurred in a non-toxic manner. Data from antimicrobial tests showed that MG toxicity decreased after decolorization. To optimize the MG decolorization process, the effects of operational parameters (such as the medium pH and composition, process temperature and culture agitation) were examined. The results demonstrate that M. roridum IM 6482 may be used effectively as an alternative to traditional decolorization agents.
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Biotecnologia/métodos , Poluentes Ambientais/química , Hypocreales/metabolismo , Corantes de Rosanilina/química , Corantes de Rosanilina/metabolismo , Corantes/química , Corantes/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Poluentes Ambientais/metabolismo , Proteínas Fúngicas/metabolismo , Lacase/metabolismo , Peroxidases/metabolismoRESUMO
Bacteriocins are small peptides with antimicrobial activity, that are produced by bacteria. Four classes of bacteriocins produced by lactic acid bacteria have been defined. Class IIa bacteriocins are promising candidates for industrial applications due to their high biological activity and their physicochemical properties. Divercin AS7 is a class IIa bacteriocin produced by Carnobacterium divergens AS7. It shows antibacterial activity against pathogens and food spoilage flora including Listeria spp. Little is known about the impact of class IIa bacteriocins upon eukaryotic cells. The safe use of bacteriocins as food biopreservatives requires the absence of cytotoxicity to human cells. To analyze the impact of divercin AS7 on human enterocytes, we expressed the recombinant divercin AS7 in the Escherichia coli BL21DE3pLys strain and conducted in vitro studies to evaluate the safety of recombinant divercin AS7. No cytotoxic effect on differentiated monolayer Caco-2 cells and no apoptotic appearance were observed when recombinant divercin AS7 was used at a concentration of 2 µg ml-1. In our study, divercin AS7 also did not interfere with differentiated Caco-2 cells monolayer integrity. The obtained results suggest that divercin AS7 is a promising peptide for the food industry.
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Due to antimicrobial properties, nisin is one of the most commonly used and investigated bacteriocins for food preservation. Surprisingly, nisin has had limited use in animal feed as well as there are only few reports on its influence on microbial ecology of the gastrointestinal tract (GIT). The present study therefore aimed at investigating effects of dietary nisin on broiler chicken GIT microbial ecology and performance in comparison to salinomycin, the widely used ionophore coccidiostat. In total, 720 one-day-old male Ross 308 chicks were randomly distributed to six experimental groups. The positive control (PC) diet was supplemented with salinomycin (60 mg/kg). The nisin (NI) diets were supplemented with increasing levels (100, 300, 900 and 2700 IU nisin/g, respectively) of the bacteriocin. The negative control (NC) diet contained no additives. At slaughter (35 days of age), activity of specific bacterial enzymes (α- and ß-glucosidases, α-galactosidases and ß-glucuronidase) in crop, ileum and caeca were significantly higher (P<0.05) in the NC group, and nisin supplementation decreased the enzyme activities to levels observed for the PC group. A similar inhibitory influence on bacterial activity was reflected in the levels of short-chain fatty acids (SCFA) and putrefactive SCFA (PSCFA) in digesta from crop and ileum; no effect was observed in caeca. Counts of Bacteroides and Enterobacteriacae in ileum digesta were significantly (P<0.001) decreased by nisin and salinomycin, but no effects were observed on the counts of Clostridium perfringens, Lactobacillus/Enterococcus and total bacteria. Like salinomycin, nisin supplementation improved broiler growth performance in a dose-dependent manner; compared to the NC group, the body weight gain of the NI900 and NI2700 groups was improved by 4.7 and 8.7%, respectively. Our findings suggest that dietary nisin exerts a mode of action similar to salinomycin and could be considered as a dietary supplement for broiler chickens.