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1.
PeerJ ; 11: e16094, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37818327

RESUMO

Background: The demand for lactic acid bacteria products, especially probiotics, has increased. Bacteria that increase polyphenol bioavailability and act as bio preservatives are sought after. This study aims to identify autochthonous lactic acid cultures from EMBRAPA that demonstrate ß-glucosidase activity and inhibitory effect on microbial sanitary indicators. Methods: Cell-free extracts were obtained by sonicating every 5 s for 40 min. The extracts were mixed with cellobiose and incubated at 50 °C. The reaction was stopped by immersing the tubes in boiling water. The GOD-POD reagent was added for spectrophotometer readings. Antimicrobial activity was tested against reference strains using the agar well diffusion method. Lactic cultures in MRS broth were added to 0.9 cm wells and incubated. The diameter of the inhibition zones was measured to determine the extension of inhibition. Results: Only L. rhamnosus EM1107 displayed extracellular ß-glucosidase activity, while all autochthonous strains except L. plantarum CNPC020 demonstrated intracellular activity for this enzyme. L. plantarum CNPC003 had the highest values. On the other hand, L. plantarum CNPC020, similarly to L. mucosae CNPC007, exhibited notable inhibition against sanitary indicators. These two strains significantly differed from the other five autochthonous cultures regarding S. enterica serovar Typhimurium ATCC 14028 inhibition (P < 0.05). However, they did not differ from at least one positive control in terms of inhibition against S. aureus ATCC 25923 and E. coli ATCC 25922 (P > 0.05). Therefore, it is advisable to consider these cultures separately for different technological purposes, such as phenolics metabolism or bio preservative activity. This will facilitate appropriate selection based on each specific property required for the intended product development.


Assuntos
Anti-Infecciosos , Celulases , Probióticos , Escherichia coli , Staphylococcus aureus , Probióticos/farmacologia
2.
Probiotics Antimicrob Proteins ; 15(3): 716-727, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-35029787

RESUMO

Despite functional goat milk products having emerged due to their importance for human nutrition and health, few studies have assessed the safety of consumption of goat dairy products containing potentially probiotic autochthonous lactic acid bacteria supplemented with prebiotic carbohydrates. Aiming this field, this study evaluated the safety of goat's milk fermented with Streptococcus thermophilus QGE, the autochthonous Limosilactobacillus mucosae CNPC007 culture, and the prebiotic inulin, through single- and repeated-dose oral toxicity tests (SDT and RDT, respectively) in animals. Ten female Swiss Webster mice were used for SDT evaluation - 2 groups, SDTc (20 mL/kg of filtered water) and SDTt (20 mL/kg of fermented milk) - and 40 Wistar rats for RDT - RDT3, RDT6, and RDT12 (treated with fermented milk at doses of 3 mL/kg, 6 mL/kg, and 12 mL/kg, respectively) and also RDTc (12 mL/kg of filtered water). For SDT, no signs of mortality or toxicity were observed, and the animals maintained the expected weight gain and feed intake. The RDT trials did not show mortality or signs of toxicity, as well as no change in body weight and organs, in the hematological and biochemical parameters, and also in relation to morphology and histology. Since the fermented milk did not cause any toxic effect in the conditions evaluated, it can be said that its no-adverse effect level (NOAEL) was considered to be higher than 20 mL/kg/day. Thus, the fermented milk with L. mucosae CNPC007 and inulin was considered to be of low toxicity, safe for use in rodents, and allowed for use in further studies.


Assuntos
Produtos Fermentados do Leite , Probióticos , Animais , Humanos , Ratos , Camundongos , Feminino , Leite/microbiologia , Prebióticos , Inulina/metabolismo , Streptococcus thermophilus/metabolismo , Técnicas de Cocultura , Fermentação , Ratos Wistar , Cabras , Água , Produtos Fermentados do Leite/microbiologia
3.
J Proteomics ; 217: 103692, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32068186

RESUMO

Cationic peptides found in Moringa oleifera seeds belong to different protein families and are described as the main flocculating agents of the species. In this study we report the identification and isolation of four new flocculant peptides, called Mo-HLPs 1-4, belonging to the family of hevein-like peptides, previously only known for their members' antimicrobial activity. Purification of the peptides followed two sequential membrane ultrafiltration steps and separation by reverse-phase liquid chromatography. Proteomic analyses showed that Mo-HLPs are extremely basic (pI >10) cysteine-rich molecules with molecular masses between 4.5 and 4.8 kDa and with a highly conserved chitin-binding domain. Searches in BLAST revealed high similarity of Mo-HLPs with hevein and other hevein-like peptides and 90% identity with morintides, which are members of the 8C-hevein-like subfamily found in M. oleifera leaves. Mo-HLPs microflocculation assays showed distinct coagulation/flocculation efficiencies, promoting turbidity reduction levels between 67 and 89% in synthetic turbid water. Activity variations were attributed to the substitution of some amino acids among the isoforms, which may have altered the final net charge of the molecules. The identification of Mo-HLPs represents the discovery of a new group of cationic peptides involved in the flocculation properties of M. oleifera seeds. SIGNIFICANCE: The study reveals the presence of hevein-like peptides in Moringa oleifera seeds. It is reported for the first time that members of this family have properties to act as flocculating agents of importance for water treatment processes. The identification of these peptides as well as new functional assignment broadens the horizon for speculation on new species which could act as sources of green coagulants for sustainable water treatment, and contributes to the knowledge about occurrence, distribution, molecular and active diversity of peptides belonging to the hevein-like family.


Assuntos
Moringa oleifera , Peptídeos Catiônicos Antimicrobianos , Lectinas de Plantas , Proteínas de Plantas , Proteômica , Sementes
4.
Hig. Aliment. (Online) ; 33(288/289): 579-583, abr.-maio 2019. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1482000

RESUMO

Objetivou-se analisar o comportamento fermentativo da cultura Lactobacillus plantarum CNPC 003 em leite de cabra em quatro tratamentos por 6 horas: T1 – L. plantarum CNPC 003; T2 – L. plantarum + oliogofrutose (FOS); T3 – L. plantarum + Streptococcus thermophilus; T4 – com L. plantarum + S. thermophilus + FOS. Os tratamentos estudados diferiram significativamente entre si em relação à acidez e ao pH após 6h de fermentação (p<0,05), tendo sido verificada uma influência positiva do uso de S. thermophilus e da adição de FOS sobre esses parâmetros. Do mesmo modo, a presença de FOS melhorou a viabilidade dos microrganismos estudados após 6h de fermentação. A utilização de S. thermophilus e de FOS é uma alternativa viável para o uso em leites fermentados contendo a cepa nativa L. plantarum CNPC 003.


Assuntos
Animais , Lactobacillus plantarum/química , Leite/química , Oligossacarídeos/administração & dosagem , Oligossacarídeos/efeitos adversos , Streptococcus thermophilus , Acidificação , Alimentos Fermentados , Cabras
5.
Biosci. j. (Online) ; 31(1): 204-214, jan./fev. 2015.
Artigo em Português | LILACS | ID: biblio-963764

RESUMO

No presente estudo objetivou-se avaliar a degradação do bagaço de cana-de-açúcar (BCA) integral (BIN) ou hidrolisado (BH) pela microbiota ruminal de caprinos e ovinos de raças naturalizadas do Nordeste brasileiro e o potencial desses animais como fontes de microrganismos e/ou enzimas celulolíticas para degradação da fibra do BCA. Para hidrólise do BCA foi utilizada uma solução de NaOH a 50%, 30% na matéria seca (MS). Foram determinadas as concentrações de MS, proteína bruta (PB), cinzas (CZ), fibra detergente neutro (FDN), fibra detergente ácido (FDA), celulose (Cel), hemicelulose (Hcel) e lignina (Lig). A degradação in situ da FDN do BH foi determinada pela incubação ruminal em sacos de náilon nos tempos: 0, 6, 24 e 96 horas. A técnica de duas etapas preconizada por Tilley e Terry foi utilizada para determinar a digestibilidade in vitro da MS (DIVMS). Foi coletado conteúdo ruminal dos animais quatro horas após a infusão de 100g de BIN via fístula ruminal para a separação de microrganismos associados às fases líquida e sólida, utilizando filtragem e extração com tampão fosfato de sódio 50 mM e pH 6,9, respectivamente. A fração sólida foi submetida ao cultivo in vitro com o substrato BIN, por 96 horas, para determinação da taxa de degradação da MS, FDN e atividade celulolítica. O pH foi determinado nos tempos de cultivo de 24, 48 e 96 horas. O pré-tratamento com NaOH aumentou a DIVMS (P<0,05). Não houve efeito de espécie sobre a DIVMS (P>0,05). A inclusão de NaOH aumentou a degradação in situ da FDN, apresentando os ovinos menor tempo de colonização (TC). Houve solubilização da Hcel, da Cel e da Lig no BCA pré-tratado com NaOH. A atividade celulolítica se concentrou na fração sólida independente da espécie doadora do inóculo, sendo observado crescimento microbiano no cultivo in vitro do BIN a partir dessa fração. O pH aumentou com o tempo de cultivo in vitro. Microrganismos ruminais de caprinos e ovinos naturalizados do Nordeste brasileiro colonizaram e degradaram o BIN e BH. O NaOH pode ser utilizado no pré-tratamento alcalino do BCA.


The purpose of this study was to evaluate the biodegradation of sugar cane bagasse (SCB), whole (WB) or hydrolyzed (HB) by ruminal microorganisms from Brazilian naturalized goat and sheep breeds, and the animals' potential as a source of microorganisms and/or cellulolytic enzymes for the biodegradation of SCB fiber. SCB hydrolysis was performed using 50% sodium hydroxide solution on 30% of dry matter (DM). The concentrations of DM, crude protein (CP), ether extract (EE), ash, neutral detergent fiber (NDF), acid detergent fiber (ADF), cellulose (Cel), hemicellulose (Hcel) and lignin (Lig) were determined in the WB and HB. For the in situ biodegradation of NDF, the HB was placed in nylon bags and incubated in rumen for 0, 6, 24 and 96 hours. The two-step technique recommended by Tilley and Terry was used to determine the in vitro digestibility of DM (IVDDM). Four hours after infusion of WB (100 g) through the ruminal fistula, the rumen content was collected from the animals and the microorganisms associated with the liquid and solid phases were separated, the former by filtration and the latter by extraction with 50 mM sodium phosphate buffer, pH 6.9. The solid fraction was subjected to in vitro culture with WB substrate for 96 hours to determine the biodegradation rate of DM, NDF and cellulolytic activity. The pH was measured after culture times of 24, 48 and 96 hours. Pretreatment with NaOH increased the IVDDM (P <0.05). No species effect on the IVDDM was detected (P> 0.05). The addition of NaOH increased the in situ biodegradation rate of NDF, with sheep showing a lower lag time (LT). There was a solubilization of Hcel, Cel and Lig in SCB pretreated with NaOH. Cellulolytic activity was higher in the solid phase, irrespective of the inoculum source, and microbial growth was observed in in vitro cultures using microorganisms from the solid phase and WB as substrate. The pH of the in vitro culture increased over time. Ruminal microorganisms from Brazilian naturalized goat and sheep breeds successfully colonized and biodegraded both WB and HB. Sodium hydroxide proved useful as an alkaline pretreatment for SCB.


Assuntos
Hidróxido de Sódio , Ruminantes , Ovinos , Saccharum , Enzimas
6.
Rev Bras Parasitol Vet ; 23(2): 136-43, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25054490

RESUMO

Bioactive molecules of plant species are promising alternatives for the chemical control of gastrointestinal nematodes in ruminants. Extracts of native and exotic seed species from Brazil's semi-arid region were tested in vitro in an egg hatch assay and the bioactivity of their proteins was investigated. Each seed species was subjected to three extractions with three types of solvents. All the seeds showed ovicidal activity, which varied according to the solvents. Higher ovicidal activity was found in the molecule fractions of low molecular weight (<12 kDa) for Albizia lebbeck, Ipomoea asarifolia, Jatropha curcas, Libidibia ferrea, Moringa oleifera and Ricinus communis (P<0.05, Bonferroni test). The two fractions of Crotalaria spectabilis showed the same ovicidal activity (P>0.05, Bonferroni test). Hemagglutinating activity was detected in the fractions of C. spectabilis and M. oleifera fractions, hemolysin activity in the A. lebbeck and M. oleifera fractions, serine protease inhibitory activity in the A. lebbeck, I. asarifolia, J. curcas, M. oleifera and R. communis fractions, cysteine protease inhibitor activity in the M. oleifera fraction, and no protein activity in the L. ferrea fraction. The results of this work reveal new plant species with a potential for use in controlling nematode parasites in goats, thus opening a new field of research involving plant protein molecules with ovicidal properties.


Assuntos
Haemonchus/efeitos dos fármacos , Proteínas Hemolisinas/farmacologia , Lectinas/farmacologia , Óvulo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Inibidores de Proteases/farmacologia , Sementes , Animais
7.
Rev. bras. parasitol. vet ; 23(2): 136-143, 06/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-714779

RESUMO

Bioactive molecules of plant species are promising alternatives for the chemical control of gastrointestinal nematodes in ruminants. Extracts of native and exotic seed species from Brazil's semi-arid region were tested in vitro in an egg hatch assay and the bioactivity of their proteins was investigated. Each seed species was subjected to three extractions with three types of solvents. All the seeds showed ovicidal activity, which varied according to the solvents. Higher ovicidal activity was found in the molecule fractions of low molecular weight (<12 kDa) for Albizia lebbeck, Ipomoea asarifolia, Jatropha curcas, Libidibia ferrea, Moringa oleifera and Ricinus communis (P<0.05, Bonferroni test). The two fractions of Crotalaria spectabilis showed the same ovicidal activity (P>0.05, Bonferroni test). Hemagglutinating activity was detected in the fractions of C. spectabilis and M. oleifera fractions, hemolysin activity in the A. lebbeck and M. oleifera fractions, serine protease inhibitory activity in the A. lebbeck, I. asarifolia, J. curcas, M. oleifera and R. communis fractions, cysteine protease inhibitor activity in the M. oleifera fraction, and no protein activity in the L. ferrea fraction. The results of this work reveal new plant species with a potential for use in controlling nematode parasites in goats, thus opening a new field of research involving plant protein molecules with ovicidal properties.


Moléculas bioativas de espécies vegetais são alternativas promissoras ao controle químico dos nematoides gastrintestinais em ruminantes. Extratos de sementes de espécies nativas e exóticas do Semiárido Brasileiro foram testados in vitro em ensaio de eclosão de ovos e investigada a natureza proteica da bioatividade. Três extrações com três solventes foram feitas para cada semente estudada. Todas as sementes apresentaram atividade ovicida, variando com o solvente utilizado. Maior taxa de inibição da eclosão concentrou-se nas frações de moléculas de baixa massa molecular (<12 kDa) para Albizia lebbeck, Ipomoea asarifolia, Jatropha curcas, Libidibia ferrea, Moringa oleifera e Ricinus communis (P<0,05, teste de Bonferroni). Crotalaria spectabilis mostrou atividade nas duas frações, sem diferença entre elas (P>0,05, teste de Bonferroni). Observou-se atividade hemaglutinante nas frações de C. spectabilis e M. oleifera, de hemolisina em A. lebbeck e M. oleifera, de atividade inibidora de protease da serina em A. lebbeck, I. asarifolia, J. curcas, M. oleifera e R. communis, de atividade inibidora de protease da cisteína em M. oleifera e nenhuma atividade proteica na fração de L. ferrea. Os resultados revelaram novas espécies botânicas com potencial de controle de nematoides em caprinos e um novo campo de pesquisa, o estudo de moléculas de origem proteica com atividade ovicida.


Assuntos
Animais , Haemonchus/efeitos dos fármacos , Proteínas Hemolisinas/farmacologia , Lectinas/farmacologia , Óvulo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Inibidores de Proteases/farmacologia , Sementes
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