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Electron. j. biotechnol ; 48: 62-71, nov. 2020. tab, graf
Article in English | LILACS | ID: biblio-1254807


BACKGROUND: A key challenge for manufacturers of pro-health food containing active probiotic microorganisms is to develop a product with attractive sensory features along with maintenance of declared number of microorganisms during storage and transfer by alimentary tract. RESULTS: The highest concentration of polyphenols was observed in snacks without an additive of probiotics as well as those with an additive of L. rhamnosus and B. animalis bacteria and concentration of these compounds increased by 9.5% during six months of storage. None of the products distinguished itself in the sensorial assessment although each was assessed positively. The number of microorganisms was stable and comparatively high during six months of storage at a room temperature and in cooling conditions (108 cfu/g). In the digestion model, an influence of aggressive digestion conditions was examined in the alimentary tract on the number of microorganisms, which allowed to arrange strains from the most resistant (S. boulardii) to the most sensitive (B. breve). It must be noted that currently on the market there is no available snack containing probiotic yeast as well as there is no literature data on works on such formulation of food. CONCLUSIONS: In the newly developed snack made of chocolate, in which sugar has been replaced with maltitol, a raw material was added in the form of raspberry, prebiotic in the form of inulin and a strain of probiotic bacteria, including the unprecedented so far S. boulardii, which stands a high chance to occupy a good place on the market of functional food.

Probiotics , Functional Food , Chocolate/microbiology , Sugar Alcohols , Temperature , Whole Foods , Digestion , Food Storage , Prebiotics , Synbiotics , Polyphenols , Snacks , Rubus , Maltose/analogs & derivatives
Electron. j. biotechnol ; 37: 1-10, Jan. 2019. tab, graf, ilus
Article in English | LILACS | ID: biblio-1048922


BACKGROUND: Chia seeds are gaining increasing interest among food producers and consumers because of their prohealth properties. RESULTS: The aim of this work was to evaluate the potential of chia seeds to act as acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitors. The highest inhibitory activity against AChE and BChE was observed for colored seed ethanol extracts. A positive correlation was found between the presence of quercetin and isoquercetin as well as protocatechuic, hydroxybenzoic, and coumaric acids and the activity of extracts as AChE and BChE inhibitors. It has also been shown that grain fragmentation affects the increase in the activity of seeds against cholinesterases (ChE). Furthermore, seeds have been shown to be a source of substances that inhibit microbial growth. CONCLUSIONS: It was found that the chia seed extracts are rich in polyphenols and inhibit the activity of ChEs; therefore, their use can be considered in further research in the field of treatment and prevention of neurodegenerative diseases.

Seeds/chemistry , Butyrylcholinesterase , Cholinesterase Inhibitors , Salvia/chemistry , Anti-Infective Agents/metabolism , In Vitro Techniques , Flavonols/analysis , Phenolic Compounds/analysis , Polyphenols/analysis , Food Additives
Electron. j. biotechnol ; 37: 25-33, Jan. 2019. tab, graf, ilus
Article in English | LILACS | ID: biblio-1051225


Background: Ammonium stress is a prime limiting phenomenon that occurs during methane formation from poultry manure. It is caused by elevated ammonium nitrogen concentrations that result from substrate decomposition. The amounts of methane formed depend on the activity of methanogenic microbes. Results: During the research reported in this paper, the response of a mesophilic consortium inhabiting a biogas reactor to rising load of poultry manure was investigated. The taxonomic composition of bacterial population was mostly typical, however syntrophic bacteria were not detected. This absence resulted in limitation of succession of some methanogenic microorganisms, especially obligate hydrogenotrophs. The methanogenic activity of the consortium was totally dependent on the activity of Methanosaeta. Inhibition of methanoganesis was noticed at ammonium nitrogen concentration of 3.68 g/L, total cessation occurred at 5.45 g/L. Significant amounts of acetic acid in the fermentation pulp accompanied the inhibition. Conclusions: The effectiveness of the consortium was totally dependent on the metabolic activity of the acetoclastic Methanoseata genus and lack of SAOB did not allow hydrogenotrophic methanogens to propagate and lead to cessation of biogas production at an elevated ammonium concentration at which acetoclastic methanogens were inhibited.

Methanosarcinaceae/metabolism , Biofuels , Microbiota , Anaerobiosis , Poultry , Stress, Physiological , Polymerase Chain Reaction , DNA Fingerprinting , Chromatography, High Pressure Liquid , Archaea/metabolism , Biodiversity , Fermentation , Microbial Consortia , Ammonium Compounds , Manure , Methane , Nitrogen
Electron. j. biotechnol ; 40: 22-29, July. 2019. tab, graf
Article in English | LILACS | ID: biblio-1053216


Background: Rosemary (Rosmarinus officinalis) contains active substances that have desirable properties for industrial and herbal medicine applications, e.g., essential oils (1.5­2.5%), tannins, flavonoids, triterpenes, saponins, resins, phytosterols, rosmarinic acid and many others. The aim of this study was to determine the influence of rosemary extract and 20% rapeseed oil substitution for animal fat on storage changes and inhibition of cholinesterases in liver pâté. Results: Preliminary research showed that rosemary extract exhibited antioxidative activity in the system of accelerated Rancimat and Oxidograph tests. Then, rosemary extract was used as an ingredient in liver pâté. During the experiment, meat samples were refrigerated and tested on days 1, 5, 8, 12 and 15 after production. The study proved that the substitution of 20% of animal fat with rapeseed oil decreased the content of saturated acids and increased the content of monoenic fatty acids by approximately 5% and polyene fatty acids by 40%. Conclusions: In addition to antioxidative activity, the rosemary extract affected the health-promoting value of the samples, which inhibited cholinesterase activity during the entire storage period. The extract inhibited AChE more than BChE.

Plant Extracts/chemistry , Cholinesterase Inhibitors , Rosmarinus/chemistry , Meat Products , Antioxidants/chemistry , Peroxides , Oils, Volatile , Fat Substitutes , Principal Component Analysis , Fatty Acids/analysis , Liver , Meat Products/microbiology
Ciênc. rural (Online) ; 49(4): e20180863, 2019. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1045331


ABSTRACT: The aim of this study was to examine the impact of cultivar and spear color on the composition of polyphenols in asparagus spears (Asparagus officinalis). The five genotypes (Schwetzinger Meisterschuss, Huchel's Alpha, Gijnlim, Grolim and Eposs) and three growing conditions of asparagus spears (Asparagus officinalis) were investigated. The polyphenols were determined by applying the HPLC-DAD system. The obtained results were subjected to the principal component analysis. Among the analyzed asparagus samples cv. Grolim contained the highest amounts of phenolic acids and flavonols. The varied quantitative and qualitative composition of polyphenolics resulted most probably from changes occurring during vegetation, such as a lack of access to light in the case of white asparagus and limited access to light in purple asparagus. The scavenging activity on DPPH radicals by asparagus extract is dependent on the variety and color and was the greatest for green asparagus samples. Similar green extracts scavenged ABTS radicals to the highest degree. Results of this study suggested that asparagus may constitute a good source of natural antioxidants to be used in our diet as well as by industries for functional food formulations.

RESUMO: O objetivo deste estudo foi examinar o impacto da cor da cultivar e da cor dos turiões na composição de polifenóis em aspargos (Asparagus officinalis). Os cinco genótipos (Schwetzinger Meisterschuss, Huchel's Alpha, Gijnlim, Grolim e Eposs) e três condições de cultivo de aspargos (Asparagus officinalis) foram investigados. Os polifenóis foram determinados aplicando o sistema HPLC-DAD. Os resultados obtidos foram submetidos à análise de componentes principais. Entre as amostras de aspargos analisadas a cv. Grolim continha as maiores quantidades de ácidos fenólicos e flavonóis. A composição quantitativa e qualitativa variada dos polifenóis resultou muito provavelmente de mudanças ocorridas durante a vegetação, como a falta de acesso à luz no caso dos aspargos brancos e o acesso limitado à luz nos aspargos purpúreos. A atividade sequestradora dos radicais DPPH pelo extrato de aspargos é dependente da variedade e cor, sendo que foi a maior para as amostras de aspargos verdes. Extratos verdes semelhantes capturaram os radicais ABTS no mais alto grau. Os resultados deste estudo sugerem que os espargos podem constituir uma boa fonte de antioxidantes naturais a serem utilizados em nossa dieta, bem como pelas indústrias para formulações de alimentos funcionais.

Electron. j. biotechnol ; 32: 41-46, Mar. 2018. tab, ilus, graf
Article in English | LILACS | ID: biblio-1022633


Background: In view of the current low efficacy of bacterial infection treatment the common trend towards searching for antibiotic systems exhibiting synergistic action is well justified. Among carbapenem analogues a particularly interesting option is provided by combinations of clavulanic acid with meropenem, which have proven to be especially effective. Results: Determination of the minimal inhibitory concentration (MIC) along with the method based on flow cytometry constitutes an important tool in the identification of bacterial sensitivity to active substances. Within this study the inhibitory effect of doripenem, clavulanic acid and the doripenem-clavulanate acid system was analyzed in relation to such bacteria as Salmonella enteritidis, Salmonella typhimurium, Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris, Clostridium butyricum and Clostridium pasteurianum, Acinetobacter baumannii, Enterobacter aerogenes. The lowest MIC, amounting to 0.03 µg/mL, was observed for the doripenem-clavulanate acid system in the case of E. coli ATCC 25922. In turn, the lowest MIC for doripenem applied alone was recorded for K. pneumoniae ATCC 31488, for which it was 0.1 µg/mL. The strain which proved to be most resistant both to doripenem and the doripenem-clavulanate acid system, was A. baumannii, with MIC of 32 µg/mL (clinical isolate) and 16 µg/mL (reference strain). Cytometric analysis for P. aeruginosa ATCC 27853 and S. aureus ATCC 25923 showed changes in cells following exposure to limiting concentrations of the active substance. Conclusions: Analysis of MIC supplies important information concerning microbial sensitivity to active substances, mainly in terms of limiting concentrations causing mortality or vitality of the tested species, which is essential when selecting appropriate antibiotic therapy.

Bacteria/drug effects , Clavulanic Acids/pharmacology , /pharmacology , Anti-Bacterial Agents/pharmacology , Pseudomonas aeruginosa/drug effects , Salmonella/drug effects , Staphylococcus aureus/drug effects , Microbial Sensitivity Tests , Clostridium/drug effects , Drug Interactions , Flow Cytometry , Klebsiella pneumoniae/drug effects