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1.
Braz. j. biol ; 84: e257516, 2024. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1374695

RESUMO

The current study describes the presence of Bacillus cereus (B. cereus) in contaminated foods of animal source and ready for human consumption with highlighting on their virulence contributing factors by detection of its virulence genes in addition to identification of their sequencing. Three hundred sixty food samples categorized as (228) meat products and (132) milk products were examined for B. cereus isolation and all of these isolates were confirmed by biochemical tests. Eighteen strains obtained from different food samples were examined for the attendance of a number of virulence genes (nheA, cytK, entFM, bceT and hblC genes) using uniplex PCR method. Furthermore, the B. cereus strains were valued for the sequencing of described genes. Generally 24.44% (88/360) food samples classified as 11.11% (40/360) meat products and 13.33% (48/360) milk products carried B. cereus according to cultural and biochemical properties, with geometric mean (1.5×107±0.15 CFU/g or mL) . The highest counts (above 105 CFU/g or mL) were originated from milk products (with geometric mean 2.2×107±0.22 CFU/g or mL) more than meat products (with geometric mean 1×107±0.19 CFU/g or mL). The results revealed that all of our isolates had one or more virulence (enterotoxin) genes. In our research, the most predominant genes were nheA (100%), followed by cytK (61.11%), entFM (33.33%), bceT (11.11%) then hblC (5.56%). Molecular method detected that overall, 5 strains (27.78%) harbored only 1 gene (nheA), 7 strains (38.88%) harbored 2 genes which classified as 5 strains (27.78%) (nheA and cytK), 2 strains (11.11%) have (nheA and entFM). Moreover, 5 strains (27.78%) have 3 genes classified as 3 strains (16.67%) harbored (nheA, cytK and entFM), 1 strain (5.56%) had (nheA, cytK and hblC), and 1 strain (5.56%) had (nheA, cytK and bceT). Only 1 strain (5.56%) carried 4 tested virulence genes (nheA, cytK, entFM and bceT) genes. The most prevalent gene in meat and dairy foods was nheA (100%). The nucleotide sequences of (bceT, cytK, entFM, hblC and nheA genes) of B. cereus strains were deposited in GenBank under accession no. (MW911824, MW911825, MW911826, MW911827 and MW911828), respectively. Our study was established to indicate the presence of virulent B. cereus in meat and milk products ready for human consumption as a result of deficient hygienic actions. So, a plain for good hygienic measures should be modified to avoid causing serious health problems to human due to ingestion of such products.


O presente estudo descreve a presença de Bacillus cereus em alimentos contaminados de origem animal e prontos para consumo humano, com destaque para seus fatores de contribuição de virulência por meio da detecção de seus genes de virulência, além da identificação de seu sequenciamento. Trezentas e sessenta amostras de alimentos categorizados como produtos cárneos (228) e produtos lácteos (132) foram examinadas para isolamento de B. cereus, e todos esses isolados foram confirmados por testes bioquímicos. Dezoito cepas obtidas de diferentes amostras de alimentos foram examinadas para a presença de uma série de genes de virulência (genes nheA, cytK, entFM, bceT e hblC) usando o método de PCR uniplex. Além disso, as cepas de B. cereus foram avaliadas para o sequenciamento dos genes descritos. De forma geral, 24,44% (88/360) das amostras de alimentos classificados como produtos cárneos (11,11%; 40/360) e produtos lácteos (13,33%; 48/360) transportavam B. cereus, de acordo com as propriedades culturais e bioquímicas, com média geométrica de 1,5 × 10 7 ± 0,15 CFU/g ou mL. Os resultados revelaram que todos os nossos isolados tinham um ou mais genes de virulência (enterotoxina). Em nossa pesquisa, os genes mais predominantes foram nheA (100%), seguidos de cytK (61,11%), entFM (33,33%), bceT (11,11%) e hblC (5,56%). O método molecular detectou que, no geral, 5 cepas (27,78%) apresentavam apenas 1 gene (nheA) e 7 cepas (38,88%) continham 2 genes que foram classificados como 5 cepas (27,78%) (nheA e cytK), 2 cepas (11,11%) possuíam (nheA e entFM). Além disso, 5 cepas (27,78%) continham 3 genes classificados como 3 cepas (16,67%) hospedados (nheA, cytK e entFM), 1 cepa (5,56%) tinha (nheA, cytK e hblC) e 1 cepa (5,56%) teve (nheA, cytK e bceT). Apenas 1 cepa (5,56%) carregava 4 genes de virulência testados (nheA, cytK, entFM e bceT). As sequências de nucleotídeos (genes bceT, cytK, entFM, hblC e nheA) de cepas de B. cereus foram depositadas no GenBank sob o número de acesso (MW911824, MW911825, MW911826, MW911827 e MW911828), respectivamente. Nosso estudo foi estabelecido para indicar a virulência de B. cereus em carnes e produtos lácteos prontos para consumo humano como resultado de ações higiênicas deficientes. Portanto, deve ser estabelecido um plano com boas medidas de higiene para evitar sérios problemas de saúde humana por causa da ingestão de tais produtos.


Assuntos
Animais , Bacillus cereus/genética , Contaminação de Alimentos , Laticínios , Carne , Egito
2.
Braz. j. biol ; 84: e257473, 2024. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1374639

RESUMO

Feathers make up 7% of the total weight of adult chickens and keratin protein makes up 85% of the feathers. Today, the keratinase enzymes of some Bacillus strains are used to degrade and process raw keratin waste for animal and poultry feed. According to various studies, the probiotic properties of some spore-shaped Bacillus have also been proven. The study aimed to isolation of the keratinolytic Bacillus bacteria that they have probiotic properties for using in the livestock and poultry feed industry. We were able to isolate 8 strains of Bacillus licheniformis with kreatin degrading properties from the soil of Baharan chicken slaughterhouse (Qom city, Iran) applying heat shock, alcohol- and keratin-rich culture medium, and after microscopic and biochemical analysis, 16S rDNA gene was isolated. The measurement results of keratinase activity showed that the three strains of Bacillus licheniformis pvkr6, pvkr 15, and pvkr41 had the highest activity with 124.08, 101.1, and 100.18 U/ml. The results of probiotic properties evaluation also revealed that among all the isolates, only Bacillus licheniformis pvkr15 and Bacillus licheniformis PTCC 1595 (positive control) were γ-hemolytic strains. The percentage of surface hydrophobicity of the strains was obtained from 3.27 to 30.57. It was also shown that, on average, all the strains had acceptable susceptibility to the tested antibiotics except penicillin G. Bacillus licheniformis pvkr15 with highest keratinase activity (101.1U/ml) was considered an optional probiotics due to its abilities such as (biofilm formation, being safe cause of γ-hemolytic activity, high susceptibility to antibiotics such as streptomycin, gentamicin, cefixime, amoxicillin, tetracycline, vancomycin, erythromycin and having a moderate hydrophilic (hydrophobicity: 19.09%), high survivability in pH 2, 2.5 and 3, strong resistance to bile salts and moderate antagonistic activity against pathogenic bacterium like Proteus mirabilis and the ability to grow under anaerobic conditions). By using this strain, after hydrolysis of keratin protein in the feather structure, to replace part of the protein of livestock and poultry feed, not only is no need to separate bacteria from the feed, but also the strain play role of an useful and effective additive in animal growth.


As penas representam 7% do peso total das galinhas adultas e a proteína de queratina compõe 85% das penas. Hoje, as enzimas queratinase de algumas cepas de Bacillus são usadas para degradar e processar resíduos de queratina brutos para alimentação de animais e aves. De acordo com vários estudos, as propriedades probióticas de alguns Bacillus em forma de esporos também foram comprovadas. O estudo teve como objetivo o isolamento das bactérias queratinolíticas Bacillus que possuem propriedades probióticas para uso na indústria de ração animal e avícola. Conseguimos isolar 8 cepas de Bacillus licheniformis com propriedades degradantes de creatina do solo do abatedouro de frangos de Baharan (cidade de Qom, Irã) aplicando choque térmico, meio de cultura rico em álcool e queratina e, após análise microscópica e bioquímica, o gene 16S rDNA foi isolado. Os resultados da medição da atividade da queratinase mostraram que as três cepas de Bacillus licheniformis pvkr6, pvkr15 e pvkr41 tiveram a maior atividade com 124,08, 101,1 e 100,18 U/ml. Os resultados da avaliação das propriedades probióticas também revelaram que dentre todos os isolados apenas Bacillus licheniformis pvkr15 e Bacillus licheniformis PTCC 1595 (controle positivo) eram cepas γ-hemolíticas. A porcentagem de hidrofobicidade superficial das cepas foi obtida de 3,27 a 30,57. Também foi demonstrado que, em média, todas as cepas apresentaram suscetibilidade aceitável aos antibióticos testados, exceto penicilina G. Bacillus licheniformis pvkr15 com maior atividade de queratinase (101,1U/ml) foi considerado um probiótico opcional devido às suas habilidades como formação de biofilme, sendo causa segura de atividade γ-hemolítica, alta suscetibilidade a antibióticos como estreptomicina, gentamicina, cefixima, amoxicilina, tetraciclina, vancomicina, eritromicina e ter uma hidrofílica moderada (hidrofobicidade: 19,09%), alta capacidade de sobrevivência em pH 2, 2,5 e 3, forte resistência aos sais biliares e atividade antagonista moderada contra bactérias patogênicas como Proteus mirabilis e a capacidade de crescer em condições anaeróbicas. Ao utilizar esta cepa, após a hidrólise da proteína queratina na estrutura da pena, para substituir parte da proteína da ração de gado e aves, não só não há necessidade de separar as bactérias da ração, mas também a cepa desempenha um papel útil e eficaz aditivo no crescimento animal.


Assuntos
Animais , Solo , Resíduos , Probióticos , Bacillus licheniformis , Queratinas , Ração Animal
3.
Braz. j. biol ; 84: e256933, 2024. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1364505

RESUMO

Anticarsia gemmatalis Hünber, 1818 is one of the main defoliating species in the soybean crop. Bacillus thuringiensis Berliner, 1915, is a bacterium used in the biological control of this pest species. Resistant populations and their sublethal effects caused by the use of the bacteria have already been reported; however, there are no studies on phenotypic plasticity in adulthood exposed to Bt-based bioinsecticide sub-doses. This study aimed to evaluate the morphometry of A. gemmatalis adults under laboratory conditions submitted to the Bt-based bioinsecticide Dipel® over the three generations. The body segments mensuread were width, length, and area of the anterior and posterior wings, the weight of the integument, chest, abdomen, wings, and the whole adult of males and females. Among the treatments, LC5 in the first generation and LC10 in the second generation were those with lower thresholds in relation to the weight of the chest and abdomen, considering the proportions of the body smaller than the females. The female's weight adulthood was reduced by 10% about males, and, only in the first generation. Males have larger body size and more pronounced phenotypic plasticity than females. Here, we demonstrate the first study assessing the phenotypic plasticity of A. gemmatalis adults.


Anticarsia gemmatalis Hünber, 1818 é uma das principais espécies desfolhadoras da cultura da soja. Bacillus thuringiensis Berliner, 1915, é uma bactéria utilizada no controle biológico dessa espécie de praga. Populações resistentes e seus efeitos subletais causados pelo uso da bactéria já foram relatados, no entanto, não há estudos sobre a plasticidade fenotípica na idade adulta exposta a subdoses de bioinseticida à base de Bt. Este trabalho teve como objetivo avaliar a morfometria de adultos de A. gemmatalis em condições de laboratório submetidos ao bioinseticida Dipel® ao longo de três gerações. Os segmentos corporais mensuráveis eram largura, comprimento e área das asas anterior e posterior, o peso do tegumento, tórax, abdômen, asas e todo o adulto de machos e fêmeas. Dentre os tratamentos, CL5 na primeira geração e CL10 na segunda geração foram aqueles com limiares mais baixos em relação ao peso do tórax e abdômen, considerando as proporções do corpo menores que as do sexo feminino. O peso da fêmea na idade adulta foi reduzido em 10% em relação aos machos e, apenas na primeira geração. Os machos têm tamanho corporal maior e plasticidade fenotípica mais pronunciada do que as fêmeas. Este estudo demonstra o primeiro estudo avaliando a plasticidade fenotípica de adultos de A. gemmatalis.


Assuntos
Animais , Fenótipo , Soja , Bacillus thuringiensis , Controle Biológico de Vetores
4.
Food Chem ; 399: 133993, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36029678

RESUMO

At present, uncovering how to preventandcontrol hyperuricemia has become an important public health issue. Fermented traditionalChinesemedicine has exhibited promising applications in the clinical management of hyperuricemia. In this study, we generated a hyperuricemic mouse model to explore the potent therapeutic ability of Bacillus subtilis-fermented Astragalus membranaceus (BFA) on this condition by multi-omics analysis. We found that the serum uric acid level was decreased in hyperuricemic mice after BFA treatment. BFA effectively attenuated renal inflammation and regulated the expression of urate transporters. Additionally, we found that BFA could increase the abundances of butyrate-producing bacteria, including Butyricimonas synergistica, Odoribacter splanchnicus, and Collinsella tanakaei, and probiotics, including Lactobacillus intestinalis and Bacillus mycoides, in hyperuricemic mice. Therefore, we believe that BFA has the potential to become a novel safe and valid functional food for addressing hyperuricemia.


Assuntos
Microbioma Gastrointestinal , Hiperuricemia , Animais , Astragalus propinquus/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Hiperuricemia/tratamento farmacológico , Hiperuricemia/genética , Rim , Camundongos , Ácido Úrico/metabolismo
5.
Food Chem ; 400: 134001, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36084586

RESUMO

Flavonoids are associated with health benefits, but most of them have poor oral bioavailability due to their extremely low aqueous solubility. Flavonoid O-phosphorylation suggests a potent modification to solve the problems. Here, we isolated, identified and characterized an unprecedented phosphotransferase, flavonoid phosphate synthetase (BsFPS), from B. subtilis. The enzyme catalyzes the ATP-dependent phosphorylation of flavonoid to generate flavonoid monophosphates, AMP and orthophosphate. BsFPS is a promiscuous phosphotransferase that efficiently catalyzes structurally-diverse flavonoids, including isoflavones, flavones, flavonols, flavanones and flavonolignans. Based on MS and NMR analysis, the phosphorylation mainly occurs on the hydroxyl group at C-7 of A-ring or C-4' of B-ring in flavonoid skeleton. Notably, BsFPS is regioselective for the ortho-3',4'-dihydroxy moiety of catechol-containing structures, such as luteolin and quercetin, to produce phosphate conjugates at C-4' or C-3' of B-ring. Our findings highlight the potential for developing biosynthetic platform to obtain new phosphorylated flavonoids for pharmaceutical and nutraceutical applications.


Assuntos
Flavanonas , Flavonas , Flavonolignanos , Isoflavonas , Monofosfato de Adenosina , Trifosfato de Adenosina , Bacillus subtilis , Catecóis , Flavonoides/química , Ligases , Luteolina , Preparações Farmacêuticas , Fosfatos , Fosfotransferases , Quercetina
6.
Food Chem ; 400: 134107, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36087481

RESUMO

This study evaluated the inoculation of Meyerozyma guilliermondii and Bacillus licheniformis, separately or in co-culture, in wet-processed conilon coffee. Wet fermentation was conducted for 48 h. Mesophilic bacteria, lactic acid bacteria, yeasts, and filamentous fungi were counted during fermentation. The inoculation of B. licheniformis and M. guilliermondii stimulated the multiplication of lactic acid bacteria. Acetic, citric, lactic, oxalic, malic, succinic, tartaric acids, glucose, and fructose were identified in all treatments at different concentrations. Methyl salicylate, 2-heptanol, 2-nonanol, and heptanone were found during fermentation. Methylpyrazine, 2,6-dimethylpyrazine, 2,5-dimethylpyrazine, and 3-ethyl-2,5-dimethylpyrazine identified after roasting assigned notes of "almond" and "chocolate" to the beverages. All treatments were classified as "premium," with the B. licheniformis treatment receiving the highest score. Bacillus licheniformis obtained better performance in fermentation, increasing coffee score and producing volatile compounds that provided positive sensory notes to the beverage.


Assuntos
Coffea , Lactobacillales , Bactérias/genética , Café/microbiologia , Frutose , Glucose , Heptanol , Leveduras
7.
Food Chem ; 400: 133994, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36108443

RESUMO

Fermented Spirulina (FS) could be a good strategic approach for diversifying algae-derived formulations to a current functional food market. In this study, microbial properties, total and free amino acids, protein hydrolysis, volatile organic compounds (VOCs) and sensory properties of FS and unfermented Spirulina (unFS) products by four different Lactic acid bacteria (LAB) and three different Bacillus strains were examined. The highest proteolytic activity with LAB strains was confirmed by SDS-PAGE. The increase in both total amino acid (TAA) and total essential amino acid (TEAA) concentrations were in the highest level for FS products by Bacillus strains, 70535.5 µM and 22295.4 µM, respectively. The pyrazine content, the most prevalent VOCs in unFS, reduced more remarkably in FS by LAB strains. Furthermore, the most acceptable sensory characteristics were obtained with FS products by LAB strains. These findings will provide insights toward achieving the industrialization of FS products.


Assuntos
Lactobacillales , Spirulina , Compostos Orgânicos Voláteis , Aminoácidos/metabolismo , Aminoácidos Essenciais/metabolismo , Fermentação , Lactobacillales/metabolismo , Spirulina/metabolismo , Compostos Orgânicos Voláteis/metabolismo
8.
Braz. J. Biol. ; 83: 1-9, 2023. mapas, ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-765485

RESUMO

Isla Arena is located in the coordinate 20° 70´ N - 90° 45´ W, from Campeche, Mexico. In these estuaries, the ocean mixes with fresh water, and ecosystems are concentrated where petenes and pink flamingos proliferate. Crustaceans and mollusks abound in the sea. Despite its enormous marine wealth, there are no studies carried out on which halophilic microorganisms are present in these waters. In this work, the diversity and structure of the microbial community was investigated through a metagenomics approach and corroborated for sequencing of 16S rRNA genes. It was found that the phylum Fimicutes predominates with more than 50%, in almost the same proportion of the class Bacilli and with almost 41% of relative abundance of the order Bacillales. The sequencing results showed that one of the samples presented a high percentage of similarity (99.75%) using the Nucleotide BLAST program with a peculiar microorganism: Bacillus subtilis. This microorganism is one of the best characterized bacteria among the gram-positive ones. Our results demonstrate that B. subtilis can be an efficient source of proteases, lipases and cellulases, from halophilic microbial communities located in poorly explored areas.(AU)


Isla Arena está localizada na coordenada 20°70N - 90°45W, de Campeche, México. Nesses estuários, o oceano se mistura com a água doce e os ecossistemas se concentram onde proliferam petenos e flamingos rosa. Crustáceos e moluscos abundam no mar. Apesar de sua enorme riqueza marinha, não há estudos realizados sobre a presença de microrganismos halofílicos nessas águas. Neste trabalho, a diversidade e estrutura da comunidade microbiana foram investigadas através de uma abordagem metagenômica e corroboradas para o sequenciamento de genes 16S rRNA. Verificou-se que o filo Fimicutes predomina com mais de 50%, quase na mesma proporção da classe Bacilli e com quase 41% de abundância relativa da ordem Bacillales. Os resultados do sequenciamento mostraram que uma das amostras apresentou alto percentual de similaridade (99,75%) pelo programa Nucleotide BLAST com um microrganismo peculiar: Bacillus subtilis. Nossos resultados demonstram que B. subtilis pode ser uma fonte eficiente de proteases, lipases e celulases, provenientes de comunidades microbianas halofílicas localizadas em áreas pouco exploradas.(AU)


Assuntos
Animais , Ecossistema , Microbiota/genética , RNA Ribossômico 16S/análise , Bacillus subtilis/crescimento & desenvolvimento , Bacillales/isolamento & purificação
9.
Braz. J. Biol. ; 83: 1-8, 2023. tab, ilus, graf
Artigo em Inglês | VETINDEX | ID: vti-765478

RESUMO

Chromium (VI) a highly toxic metal, a major constituent of industrial waste. It is continuously release in soil and water, causes environmental and health related issues, which is increasing public concern in developing countries like Pakistan. The basic aim of this study was isolation and screening of chromium resistant bacteria from industrial waste collected from Korangi and Lyari, Karachi (24˚52ʹ46.0ʺN 66˚59ʹ25.7ʺE and 24˚48ʹ37.5ʺN 67˚06ʹ52.6ʺE). Among total of 53 isolated strains, seven bacterial strains were selected through selective enrichment and identified on the basis of morphological and biochemical characteristics. These strains were designated as S11, S13, S17, S18, S30, S35 and S48, resistance was determined against varying concentrations of chromium (100-1500 mg/l). Two bacterial strains S35 and S48 showed maximum resistance to chromium (1600 mg/l). Bacterial strains S35 and S48 were identified through 16S rRNA sequence and showed 99% similarity to Bacillus paranthracis and Bacillus paramycoides. Furthermore, growth condition including temperature and pH were optimized for both bacterial strains, showed maximum growth at temperature 30ºC and at optimum pH 7.5 and 6.5 respectively. It is concluded that indigenous bacterial strains isolated from metal contaminated industrial effluent use their innate ability to transform toxic heavy metals to less or nontoxic form and can offer an effective tool for monitoring heavy metal contamination in the environment.(AU)


O cromo (VI), metal altamente tóxico, é um dos principais constituintes dos resíduos industriais. É liberado no solo e na água, causa problemas ambientais e de saúde de crescente preocupação pública em países em desenvolvimento como o Paquistão. O objetivo básico deste estudo foi o isolamento e a triagem de bactérias resistentes ao cromo de resíduos industriais coletados em Korangi e Lyari, Karachi (24˚5246,0”N 66˚5925,7”E e 24˚4837,5”N 67˚0652,6”E). Do total de 53 cepas isoladas, sete cepas bacterianas foram selecionadas por enriquecimento seletivo e identificadas com base em características morfológicas e bioquímicas. Essas cepas foram designadas como S11, S13, S17, S18, S30, S35 e S48, apresentaram alta resistência aos metais contra concentrações variáveis (100-1500 mg / l) de cromo. Já as cepas S35 e S48 foram identificadas por meio da sequência 16S rRNA e apresentaram 99% de similaridade com Bacillus paranthracis e Bacillus paramycoides. Além disso, as condições de crescimento incluindo temperatura e pH foram otimizadas e ambas as cepas bacterianas apresentaram crescimento máximo na temperatura de 30ºC, enquanto seu pH ótimo foi observado em 7,5 e 6,5, respectivamente. Conclui-se que o potencial de resistência dessas bactérias resistentes ao cromo pode ser efetivamente utilizado na remoção de cromo de efluentes industriais contaminados. Técnicas de base biológica usando bactérias ajudarão a fornecer métodos mais baratos e ecológicos de remoção, recuperação e desintoxicação de cromo.(AU)


Assuntos
Efluentes Industriais/análise , Cromo/toxicidade , Bacillaceae/isolamento & purificação , Bacillaceae/genética , Bacillaceae/crescimento & desenvolvimento
10.
Braz. J. Biol. ; 83: 1-6, 2023. graf
Artigo em Inglês | VETINDEX | ID: vti-765422

RESUMO

In recent days, cheapest alternative carbon source for fermentation purpose is desirable to minimize production cost. Xylanases have become attractive enzymes as their potential in bio-bleaching of pulp and paper industry. The objective of the present study was to identify the potential ability on the xylanase production by locally isolated Bacillus pumilus BS131 by using waste fiber sludge and wheat bran media under submerged fermentation. Culture growth conditions were optimized to obtain significant amount of xylanase. Maximum xylanase production was recorded after 72 hours of incubation at 30 °C and 7 pH with 4.0% substrate concentration. In the nutshell, the production of xylanase using inexpensive waste fiber sludge and wheat-bran as an alternative in place of expensive xylan substrate was more cost effective and environment friendly.(AU)


Nos últimos dias, a fonte alternativa de carbono mais barata para fins de fermentação é desejável para minimizar o custo de produção. As xilanases têm se tornado enzimas atraentes como seu potencial no biobranqueamento da indústria de papel e celulose. O objetivo do presente estudo foi identificar a capacidade potencial na produção de xilanase por Bacillus pumilus BS131 isolado localmente usando lodo de fibra residual e farelo de trigo em meio de fermentação submersa. As condições de crescimento da cultura foram otimizadas para obter uma quantidade significativa de xilanase. A produção máxima de xilanase foi registrada após 72 horas de incubação a 30 °C e pH 7 com concentração de substrato de 4,0%. Resumindo, a produção de xilanase usando lodo de fibra residual de baixo custo e farelo de trigo como uma alternativa no lugar do substrato de xilano caro foi mais econômica e ecológica.(AU)


Assuntos
Bacillus pumilus/química , Xilanos/análise , Especificidade por Substrato
11.
Braz. J. Biol. ; 83: 1-8, 2023. tab, ilus, graf
Artigo em Inglês | VETINDEX | ID: vti-765414

RESUMO

Endophytic bacteria serve key roles in the maintenance of plant health and growth. Few studies to date, however, have explored the antagonistic and plant growth-promoting (PGP) properties of Prunus cerasifera endophytes. To that end, we isolated endophytic bacteria from P. cerasifera tissue samples and used a dual culture plate assay to screen these microbes for antagonistic activity against Verticillium dahliae, Botryosphaeria dothidea, Fusarium oxysporum, F. graminearum, and F. moniliforme. Of the 36 strains of isolated bacteria, four (strains P1, P10, P16, and P20) exhibited antagonistic effects against all five model pathogens, and the P10 strain exhibited the strongest antagonistic to five pathogens. This P10 strain was then characterized in-depth via phenotypic assessments, physiological analyses, and 16s rDNA sequencing, revealing it to be a strain of Bacillus subtilis. Application of a P10 cell suspension (1×108 CFU/mL) significantly enhanced the seed germination and seedling growth of tomato in a greenhouse setting. This P10 strain further significantly suppressed tomato Verticillium wilt with much lower disease incidence and disease index scores being observed following P10 treatment relative to untreated plants in pot-based experiments. Tomato plants that had been treated with strain P10 also enhanced defense-related enzymes, peroxidase, superoxide dismutase, and catalase activity upon V. dahliae challenge relative to plants that had not been treated with this endophytic bacterium. The results revealed that the P10 bacterial strain has potential value as a biocontrol agent for use in the prevention of tomato Verticillium wilt.(AU)


As bactérias endofíticas desempenham papel fundamental na manutenção da saúde e do crescimento das plantas. Poucos estudos até o momento, no entanto, exploraram as propriedades antagônicas e promotoras de crescimento de plantas (PGP) de endófitos de Prunus cerasifera. Para esse fim, isolamos bactérias endofíticas de amostras de tecido de P. cerasifera e usamos um ensaio de placa de cultura dupla para rastrear esses micróbios quanto à atividade antagonista contra Verticillium dahliae, Botryosphaeria dothidea, Fusarium oxysporum, F. graminearum e F. moniliforme. Das 36 cepas de bactérias isoladas, quatro (cepas P1, P10, P16 e P20) exibiram efeitos antagônicos contra todos os cinco patógenos modelo, e a cepa P10 exibiu o antagonista mais forte para cinco patógenos. Essa cepa P10 foi então caracterizada em profundidade por meio de avaliações fenotípicas, análises fisiológicas e sequenciamento de rDNA 16s, revelando ser uma cepa de Bacillus subtilis. A aplicação de uma suspensão de células P10 (1 × 108 UFC / mL) aumentou significativamente a germinação das sementes e o crescimento das mudas de tomate em casa de vegetação. Essa cepa P10 suprimiu ainda mais a murcha de Verticillium do tomate com incidência de doença muito menor e pontuações de índice de doença sendo observadas após o tratamento com P10 em relação a plantas não tratadas em experimentos baseados em vasos. As plantas de tomate que foram tratadas com a cepa P10 também aumentaram as enzimas relacionadas à defesa, peroxidase, superóxido dismutase e atividade da catalase após o desafio de V. dahliae em relação às plantas que não foram tratadas com essa bactéria endofítica. Os resultados revelaram que a cepa bacteriana P10 tem valor potencial como agente de biocontrole para uso na prevenção da murcha de Verticillium em tomate.(AU)


Assuntos
Prunus/microbiologia , Bacillus subtilis/genética , Bacillus subtilis/fisiologia , Endófitos/isolamento & purificação , Verticillium/patogenicidade , Fusarium/patogenicidade
12.
Braz. j. biol ; 83: e246038, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339397

RESUMO

Abstract Isla Arena is located in the coordinate 20° 70´ N - 90° 45´ W, from Campeche, Mexico. In these estuaries, the ocean mixes with fresh water, and ecosystems are concentrated where petenes and pink flamingos proliferate. Crustaceans and mollusks abound in the sea. Despite its enormous marine wealth, there are no studies carried out on which halophilic microorganisms are present in these waters. In this work, the diversity and structure of the microbial community was investigated through a metagenomics approach and corroborated for sequencing of 16S rRNA genes. It was found that the phylum Fimicutes predominates with more than 50%, in almost the same proportion of the class Bacilli and with almost 41% of relative abundance of the order Bacillales. The sequencing results showed that one of the samples presented a high percentage of similarity (99.75%) using the Nucleotide BLAST program with a peculiar microorganism: Bacillus subtilis. This microorganism is one of the best characterized bacteria among the gram-positive ones. Our results demonstrate that B. subtilis can be an efficient source of proteases, lipases and cellulases, from halophilic microbial communities located in poorly explored areas.


Resumo Isla Arena está localizada na coordenada 20°70'N - 90°45'W, de Campeche, México. Nesses estuários, o oceano se mistura com a água doce e os ecossistemas se concentram onde proliferam petenos e flamingos rosa. Crustáceos e moluscos abundam no mar. Apesar de sua enorme riqueza marinha, não há estudos realizados sobre a presença de microrganismos halofílicos nessas águas. Neste trabalho, a diversidade e estrutura da comunidade microbiana foram investigadas através de uma abordagem metagenômica e corroboradas para o sequenciamento de genes 16S rRNA. Verificou-se que o filo Fimicutes predomina com mais de 50%, quase na mesma proporção da classe Bacilli e com quase 41% de abundância relativa da ordem Bacillales. Os resultados do sequenciamento mostraram que uma das amostras apresentou alto percentual de similaridade (99,75%) pelo programa Nucleotide BLAST com um microrganismo peculiar: Bacillus subtilis. Nossos resultados demonstram que B. subtilis pode ser uma fonte eficiente de proteases, lipases e celulases, provenientes de comunidades microbianas halofílicas localizadas em áreas pouco exploradas.


Assuntos
Archaea , Microbiota , Filogenia , Bactérias/genética , RNA Ribossômico 16S/genética , México
13.
Braz. j. biol ; 83: e242536, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339356

RESUMO

Abstract Chromium (VI) a highly toxic metal, a major constituent of industrial waste. It is continuously release in soil and water, causes environmental and health related issues, which is increasing public concern in developing countries like Pakistan. The basic aim of this study was isolation and screening of chromium resistant bacteria from industrial waste collected from Korangi and Lyari, Karachi (24˚52ʹ46.0ʺN 66˚59ʹ25.7ʺE and 24˚48ʹ37.5ʺN 67˚06ʹ52.6ʺE). Among total of 53 isolated strains, seven bacterial strains were selected through selective enrichment and identified on the basis of morphological and biochemical characteristics. These strains were designated as S11, S13, S17, S18, S30, S35 and S48, resistance was determined against varying concentrations of chromium (100-1500 mg/l). Two bacterial strains S35 and S48 showed maximum resistance to chromium (1600 mg/l). Bacterial strains S35 and S48 were identified through 16S rRNA sequence and showed 99% similarity to Bacillus paranthracis and Bacillus paramycoides. Furthermore, growth condition including temperature and pH were optimized for both bacterial strains, showed maximum growth at temperature 30ºC and at optimum pH 7.5 and 6.5 respectively. It is concluded that indigenous bacterial strains isolated from metal contaminated industrial effluent use their innate ability to transform toxic heavy metals to less or nontoxic form and can offer an effective tool for monitoring heavy metal contamination in the environment.


Resumo O cromo (VI), metal altamente tóxico, é um dos principais constituintes dos resíduos industriais. É liberado no solo e na água, causa problemas ambientais e de saúde de crescente preocupação pública em países em desenvolvimento como o Paquistão. O objetivo básico deste estudo foi o isolamento e a triagem de bactérias resistentes ao cromo de resíduos industriais coletados em Korangi e Lyari, Karachi (24˚52'46,0"N 66˚59'25,7"E e 24˚48'37,5"N 67˚06'52,6"E). Do total de 53 cepas isoladas, sete cepas bacterianas foram selecionadas por enriquecimento seletivo e identificadas com base em características morfológicas e bioquímicas. Essas cepas foram designadas como S11, S13, S17, S18, S30, S35 e S48, apresentaram alta resistência aos metais contra concentrações variáveis (100-1500 mg / l) de cromo. Já as cepas S35 e S48 foram identificadas por meio da sequência 16S rRNA e apresentaram 99% de similaridade com Bacillus paranthracis e Bacillus paramycoides. Além disso, as condições de crescimento incluindo temperatura e pH foram otimizadas e ambas as cepas bacterianas apresentaram crescimento máximo na temperatura de 30 ºC, enquanto seu pH ótimo foi observado em 7,5 e 6,5, respectivamente. Conclui-se que o potencial de resistência dessas bactérias resistentes ao cromo pode ser efetivamente utilizado na remoção de cromo de efluentes industriais contaminados. Técnicas de base biológica usando bactérias ajudarão a fornecer métodos mais baratos e ecológicos de remoção, recuperação e desintoxicação de cromo.


Assuntos
Cromo , Metais Pesados , Bacillus , Bactérias/genética , Biodegradação Ambiental , RNA Ribossômico 16S/genética , Resíduos Industriais/análise
14.
Braz. j. biol ; 83: e244261, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1285633

RESUMO

Abstract Endophytic bacteria serve key roles in the maintenance of plant health and growth. Few studies to date, however, have explored the antagonistic and plant growth-promoting (PGP) properties of Prunus cerasifera endophytes. To that end, we isolated endophytic bacteria from P. cerasifera tissue samples and used a dual culture plate assay to screen these microbes for antagonistic activity against Verticillium dahliae, Botryosphaeria dothidea, Fusarium oxysporum, F. graminearum, and F. moniliforme. Of the 36 strains of isolated bacteria, four (strains P1, P10, P16, and P20) exhibited antagonistic effects against all five model pathogens, and the P10 strain exhibited the strongest antagonistic to five pathogens. This P10 strain was then characterized in-depth via phenotypic assessments, physiological analyses, and 16s rDNA sequencing, revealing it to be a strain of Bacillus subtilis. Application of a P10 cell suspension (1×108 CFU/mL) significantly enhanced the seed germination and seedling growth of tomato in a greenhouse setting. This P10 strain further significantly suppressed tomato Verticillium wilt with much lower disease incidence and disease index scores being observed following P10 treatment relative to untreated plants in pot-based experiments. Tomato plants that had been treated with strain P10 also enhanced defense-related enzymes, peroxidase, superoxide dismutase, and catalase activity upon V. dahliae challenge relative to plants that had not been treated with this endophytic bacterium. The results revealed that the P10 bacterial strain has potential value as a biocontrol agent for use in the prevention of tomato Verticillium wilt.


Resumo As bactérias endofíticas desempenham papel fundamental na manutenção da saúde e do crescimento das plantas. Poucos estudos até o momento, no entanto, exploraram as propriedades antagônicas e promotoras de crescimento de plantas (PGP) de endófitos de Prunus cerasifera. Para esse fim, isolamos bactérias endofíticas de amostras de tecido de P. cerasifera e usamos um ensaio de placa de cultura dupla para rastrear esses micróbios quanto à atividade antagonista contra Verticillium dahliae, Botryosphaeria dothidea, Fusarium oxysporum, F. graminearum e F. moniliforme. Das 36 cepas de bactérias isoladas, quatro (cepas P1, P10, P16 e P20) exibiram efeitos antagônicos contra todos os cinco patógenos modelo, e a cepa P10 exibiu o antagonista mais forte para cinco patógenos. Essa cepa P10 foi então caracterizada em profundidade por meio de avaliações fenotípicas, análises fisiológicas e sequenciamento de rDNA 16s, revelando ser uma cepa de Bacillus subtilis. A aplicação de uma suspensão de células P10 (1 × 108 UFC / mL) aumentou significativamente a germinação das sementes e o crescimento das mudas de tomate em casa de vegetação. Essa cepa P10 suprimiu ainda mais a murcha de Verticillium do tomate com incidência de doença muito menor e pontuações de índice de doença sendo observadas após o tratamento com P10 em relação a plantas não tratadas em experimentos baseados em vasos. As plantas de tomate que foram tratadas com a cepa P10 também aumentaram as enzimas relacionadas à defesa, peroxidase, superóxido dismutase e atividade da catalase após o desafio de V. dahliae em relação às plantas que não foram tratadas com essa bactéria endofítica. Os resultados revelaram que a cepa bacteriana P10 tem valor potencial como agente de biocontrole para uso na prevenção da murcha de Verticillium em tomate.


Assuntos
Lycopersicon esculentum , Verticillium , Prunus domestica , Doenças das Plantas/prevenção & controle , Ascomicetos , Bacillus subtilis , Fusarium
15.
Braz. j. biol ; 83: e243874, 2023. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1285606

RESUMO

Abstract In recent days, cheapest alternative carbon source for fermentation purpose is desirable to minimize production cost. Xylanases have become attractive enzymes as their potential in bio-bleaching of pulp and paper industry. The objective of the present study was to identify the potential ability on the xylanase production by locally isolated Bacillus pumilus BS131 by using waste fiber sludge and wheat bran media under submerged fermentation. Culture growth conditions were optimized to obtain significant amount of xylanase. Maximum xylanase production was recorded after 72 hours of incubation at 30 °C and 7 pH with 4.0% substrate concentration. In the nutshell, the production of xylanase using inexpensive waste fiber sludge and wheat-bran as an alternative in place of expensive xylan substrate was more cost effective and environment friendly.


Resumo Nos últimos dias, a fonte alternativa de carbono mais barata para fins de fermentação é desejável para minimizar o custo de produção. As xilanases têm se tornado enzimas atraentes como seu potencial no biobranqueamento da indústria de papel e celulose. O objetivo do presente estudo foi identificar a capacidade potencial na produção de xilanase por Bacillus pumilus BS131 isolado localmente usando lodo de fibra residual e farelo de trigo em meio de fermentação submersa. As condições de crescimento da cultura foram otimizadas para obter uma quantidade significativa de xilanase. A produção máxima de xilanase foi registrada após 72 horas de incubação a 30 °C e pH 7 com concentração de substrato de 4,0%. Resumindo, a produção de xilanase usando lodo de fibra residual de baixo custo e farelo de trigo como uma alternativa no lugar do substrato de xilano caro foi mais econômica e ecológica.


Assuntos
Bacillus/metabolismo , Bacillus pumilus/metabolismo , Esgotos , Temperatura , Fibras na Dieta , Endo-1,4-beta-Xilanases/metabolismo , Fermentação , Concentração de Íons de Hidrogênio
16.
Ciênc. rural (Online) ; 53(5): e20210805, 2023. tab, graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1394267

RESUMO

ABSTRACT: An edible coating of sodium alginate incorporated with brown propolis (2.5%, 5%, 10%, and 15%) was applied to black pepper grains to improve microbiological quality over 30 days. Gas chromatography coupled with mass spectrometry identified 29 metabolites in the extract, mainly terpene compounds (51.74%), phenolic compounds (25.83%), and flavonoids (14.48%). Brown propolis showed greater antibacterial activity for Gram-positive bacteria (MIC from 0.1 to 0.5 mg.mL-1) and lower activity for Escherichiacoli (MIC 18 mg.mL-1). A 5% increase in propolis in the coating reduced Bacilluscereus counts by 7-fold, 9.4% for Staphylococcusaureus, and 5.4% for mesophilic bacteria. The edible sodium alginate coating containing brown propolis was effective in reducing microbes on black pepper, with a concentration of 15% propolis assuring the microbiological quality of the spice after 20 days.


RESUMO: Revestimento comestível de alginato de sódio incorporado com própolis marrom (2,5%, 5%, 10% e 15%) foi aplicado em grãos de pimenta-do-reino para melhorar a qualidade microbiológica ao longo de 30 dias. Análise de cromatografia gasosa associada à espectrometria de massa identificou 29 metabólitos no extrato, principalmente compostos terpênicos (51,74%), compostos fenólicos (25,83%) e flavonóides (14,48%). A própolis marrom apresentou maior atividade antibacteriana para bactérias Gram-positivas (CIM de 0,1 a 0,5 mg.mL-1) e menor atividade para Escherichia coli (CIM 18 mg.mL-1). Um aumento em 5% no revestimento da própolis reduziu a contagem de Bacillus cereus em sete vezes, 9,4% para Staphylococcus aureus e 5,4% para bactérias mesófilas. O revestimento comestível de alginato de sódio e própolis marrom foi eficaz na redução microbiana da pimenta-do-reino, em que a concentração de 15% de própolis garantiu a qualidade microbiológica da especiaria até 20 dias.

17.
Front Microbiol ; 13: 968439, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36090104

RESUMO

Proteases are important for decomposition of proteins to generate peptides or amino acids and have a broad range of applications in different industries. Herein, a gene encoding an alkaline protease (AprBcp) from Bacillus circulans R1 was cloned and bioinformatics analyzed. In addition, a series of strategies were applied to achieve high-level expression of AprBcp in Bacillus subtilis. The maximum activity of AprBcp reached 165,870 U/ml after 60 h fed-batch cultivation in 50 l bioreactor. The purified recombinant AprBcp exhibited maximum activity at 60°C and pH 10.0, and remained stable in the range from pH 8.0 to 11.0 and 30 to 45°C. Metal ions Ca2+, Mn2+, and Mg2+ could improve the stability of AprBcp. Furthermore, the recombinant AprBcp displayed great potential application on the recovery of protein from soybean dregs. The results of this study will provide an effective method to prepare AprBcp in B. subtilis and its potential application on utilization of soybean dregs.

18.
Front Microbiol ; 13: 912536, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36090105

RESUMO

Over the course of the last decades, the continuous exposure of bacteria to antibiotics-at least in parts due to misprescription, misuse, and misdosing-has led to the widespread development of antimicrobial resistances. This development poses a threat to the available medication in losing their effectiveness in treating bacterial infections. On the drug development side, only minor advances have been made to bring forward novel therapeutics. In addition to increasing the efforts and approaches of tapping the natural sources of new antibiotics, synthetic approaches to developing novel antimicrobials are being pursued. In this study, BDTL049 was rationally designed using knowledge based on the properties of natural antibiotics. BDTL049 is a carbosilane dendritic system with bow-tie type topology, which has antimicrobial activity at concentrations comparable to clinically established natural antibiotics. In this report, we describe its mechanism of action on the Gram-positive model organism Bacillus subtilis. Exposure to BDTL049 resulted in a complex transcriptional response, which pointed toward disturbance of the cell envelope homeostasis accompanied by disruption of other central cellular processes of bacterial metabolism as the primary targets of BDTL049 treatment. By applying a combination of whole-cell biosensors, molecular staining, and voltage sensitive dyes, we demonstrate that the mode of action of BDTL049 comprises membrane depolarization concomitant with pore formation. As a result, this new molecule kills Gram-positive bacteria within minutes. Since BDTL049 attacks bacterial cells at different targets simultaneously, this might decrease the chances for the development of bacterial resistances, thereby making it a promising candidate for a future antimicrobial agent.

19.
Front Microbiol ; 13: 987844, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36090114

RESUMO

Volatile organic compounds (VOCs) produced by antagonistic microorganisms have good biocontrol prospects against postharvest diseases. Infection caused by Alternaria iridiaustralis and 10 other significant fungal diseases can be successfully inhibited by VOCs produced by an identified and screened endophytic strain L1 (Bacillus velezensis). This study revealed the in vivo and in vitro biocontrol effects of VOCs released by B. velezensis L1 on A. iridiaustralis, a pathogenic fungus responsible for rot of wolfberry fruit. The inhibition rates of VOCs of B. velezensis L1 on the mycelial growth of A. iridiaustralis in vitro were 92.86 and 90.30%, respectively, when the initial inoculum concentration on the plate was 1 × 109 colony forming unit (CFU)/ml. Spore germination and sporulation were 66.89 and 87.96%, respectively. VOCs considerably decreased the wolfberry's disease index and decay incidence in vivo. Scanning electron microscopy revealed that the morphological and structural characteristics of A. iridiaustralis could be altered by VOCs. Ten VOCs were identified through headspace-gas chromatography-ion mobility spectrometry. Pure chemical tests revealed that 2.3-butanedione had the strongest antifungal effects, totally inhibiting A. iridiaustralis in wolfberry fruit at a 60 µl/L concentration. The theory underpinning the potential application of VOCs from B. velezensis is provided herein. This is also the first study to document the antifungal capabilities of the B. velezensis strain on postharvest wolfberry fruit. GRAPHICAL ABSTRACT.

20.
Front Microbiol ; 13: 971836, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36090115

RESUMO

The rhizosphere is a highly complex and biochemically diverse environment that facilitates plant-microbe and microbe-microbe interactions, and this region is found between plant roots and the bulk soil. Several studies have reported plant root exudation and metabolite secretion by rhizosphere-inhabiting microbes, suggesting that these metabolites play a vital role in plant-microbe interactions. However, the biochemical constellation of the rhizosphere soil is yet to be fully elucidated and thus remains extremely elusive. In this regard, the effects of plant growth-promoting rhizobacteria (PGPR)-plant interactions on the rhizosphere chemistry and above ground tissues are not fully understood. The current study applies an untargeted metabolomics approach to profile the rhizosphere exo-metabolome of wheat cultivars generated from seed inoculated (bio-primed) with Paenibacillus (T22) and Bacillus subtilis strains and to elucidate the effects of PGPR treatment on the metabolism of above-ground tissues. Chemometrics and molecular networking tools were used to process, mine and interpret the acquired mass spectrometry (MS) data. Global metabolome profiling of the rhizosphere soil of PGPR-bio-primed plants revealed differential accumulation of compounds from several classes of metabolites including phenylpropanoids, organic acids, lipids, organoheterocyclic compounds, and benzenoids. Of these, some have been reported to function in plant-microbe interactions, chemotaxis, biocontrol, and plant growth promotion. Metabolic perturbations associated with the primary and secondary metabolism were observed from the profiled leaf tissue of PGPR-bio-primed plants, suggesting a distal metabolic reprograming induced by PGPR seed bio-priming. These observations gave insights into the hypothetical framework which suggests that PGPR seed bio-priming can induce metabolic changes in plants leading to induced systemic response for adaptation to biotic and abiotic stress. Thus, this study contributes knowledge to ongoing efforts to decipher the rhizosphere metabolome and mechanistic nature of biochemical plant-microbe interactions, which could lead to metabolome engineering strategies for improved plant growth, priming for defense and sustainable agriculture.

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