Endophytic Bacillus subtilis P10 from Prunus cerasifera as a biocontrol agent against tomato Verticillium wilt / Bacillus subtilis P10 endofítico de Prunus cerasifera como agente de biocontrole contra murcha de Verticillium de tomate

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.

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.

Endophytic Bacillus subtilis P10 from Prunus cerasifera as a biocontrol agent against tomato Verticillium wilt / Bacillus subtilis P10 endofítico de Prunus cerasifera como agente de biocontrole contra murcha de Verticillium de tomate

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)

Effect of Bacillus Subtilis on Immune Function of Hd11 Chicken Macrophages

Poultry is frequently contaminated by Salmonella, a pathogen leading to human health concern worldwide. This study aimed to evaluate the effect of Bacillus subtilis (BS)strain 048 (BS048) on the activation, phagocytosis, sterilization, cytokine secretion, and nitrogen oxide synthesis of HD11 chicken macrophages subjected to Salmonella enteritidis challenge, using lipopolysaccharide treatment as a negative control. The results showed: (1) BS048 had no significant effect on extracellular lactate dehydrogenase activity (p>0.05), while lipopolysaccharide treatment significantly increased extracellular lactate dehydrogenase activity (p >0.05), while lipopolysaccharide treatment significantly increased extracellular lactate dehydrogenase activity (p 0.05);(2)BS048 significantly upregulated the expression levels of pro-inflammatory cytokines (interleukin (IL)- 1â and IL-6), anti-inflammatory cytokines(IL-10 and transforming growth factor-â1), and anti-viral cytokine, interferon-â (p<0.01); ; (3) BS048 significantly upregulated the mRNA expression level of the inducible nitric oxide synthase and its activity as well as extracellular nitrogen oxide level (p <0.01). In conclusion, BS048 could improve antiinflammatory and immune functions of HD11 chicken macrophages, without cytotoxic effects on these cells.(AU)

Identification by molecular techniques of halophilic bacteria producing important enzymes from pristine area in Campeche, Mexico / Identificação por técnicas moleculares de bactérias halofílicas que produzem enzimas importantes em área intocada de Campeche, México

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.

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.

Endophytic Bacillus subtilis P10 from Prunus cerasifera as a biocontrol agent against tomato Verticillium wilt / Bacillus subtilis P10 endofítico de Prunus cerasifera como agente de biocontrole contra murcha de Verticillium de tomate

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.

Significant production of vanillin and in vitro amplification of ech gene in local bacterial isolates / Produção significativa de vanilina e amplificação in vitro do gene ech em isolados bacterianos locais

Abstract Vanillin is the major component which is responsible for flavor and aroma of vanilla extract and is produced by 3 ways: natural extraction from vanilla plant, chemical synthesis and from microbial transformation. Current research was aimed to study bacterial production of vanillin from native natural sources including sewage and soil from industrial areas. The main objective was vanillin bio-production by isolating bacteria from these native sources. Also to adapt methodologies to improve vanillin production by optimized fermentation media and growth conditions. 47 soil and 13 sewage samples were collected from different industrial regions of Lahore, Gujranwala, Faisalabad and Kasur. 67.7% bacterial isolates produced vanillin and 32.3% were non-producers. From these 279 producers, 4 bacterial isolates selected as significant producers were; A3, A4, A7 and A10. These isolates were identified by ribotyping as A3 Pseudomonas fluorescence (KF408302), A4 Enterococcus faecium (KT356807), A7 Alcaligenes faecalis (MW422815) and A10 Bacillus subtilis (KT962919). Vanillin producers were further tested for improved production of vanillin and were grown in different fermentation media under optimized growth conditions for enhanced production of vanillin. The fermentation media (FM) were; clove oil based, rice bran waste (residues oil) based, wheat bran based and modified isoeugenol based. In FM5, FM21, FM22, FM23, FM24, FM30, FM31, FM32, FM34, FM35, FM36, and FM37, the selected 4 bacterial strains produced significant amounts of vanillin. A10 B. subtilis produced maximum amount of vanillin. This strain produced 17.3 g/L vanillin in FM36. Cost of this fermentation medium 36 was 131.5 rupees/L. This fermentation medium was modified isoeugenol based medium with 1% of isoeugenol and 2.5 g/L soybean meal. ech gene was amplified in A3 P. fluorescence using ech specific primers. As vanillin use as flavor has increased tremendously, the bioproduction of vanillin must be focused.

Resumo A vanilina é o principal componente responsável pelo sabor e aroma do extrato de baunilha e é produzida de três formas: extração natural da planta da baunilha, síntese química e transformação microbiana. A pesquisa atual teve como objetivo estudar a produção bacteriana de vanilina a partir de fontes naturais nativas, incluindo esgoto e solo de áreas industriais. O objetivo principal era a bioprodução de vanilina por meio do isolamento de bactérias dessas fontes nativas. Também para adaptar metodologias para melhorar a produção de vanilina por meio de fermentação otimizada e condições de crescimento. Foram coletadas 47 amostras de solo e 13 de esgoto de diferentes regiões industriais de Lahore, Gujranwala, Faisalabad e Kasur; 67,7% dos isolados bacterianos produziram vanilina e 32,3% eram não produtores. Desses 279 produtores, 4 isolados bacterianos selecionados como produtores significativos foram: A3, A4, A7 e A10. Esses isolados foram identificados por ribotipagem como fluorescência A3 Pseudomonas (KF408302), A4 Enterococcus faecium (KT356807), A7 Alcaligenes faecalis (MW422815) e A10 Bacillus subtilis (KT962919). Os produtores de vanilina foram posteriormente testados para produção aprimorada de vanilina e foram cultivados em diferentes meios de fermentação sob condições de crescimento otimizadas para produção aprimorada de vanilina. Os meios de fermentação (FM) foram: à base de óleo de cravo, à base de resíduos de farelo de arroz (resíduos de óleo), à base de farelo de trigo e à base de isoeugenol modificado. Em FM5, FM21, FM22, FM23, FM24, FM30, FM31, FM32, FM34, FM35, FM36 e FM37, as 4 cepas bacterianas selecionadas produziram quantidades significativas de vanilina. A10 B. subtilis produziu quantidade máxima de vanilina. Essa cepa produziu 17,3 g / L de vanilina em FM36. O custo desse meio de fermentação 36 foi de 131,5 rúpias / L. Esse meio de fermentação foi um meio à base de isoeugenol modificado com 1% de isoeugenol e 2,5 g / L de farelo de soja. O gene ech foi amplificado em A3 P. fluorescence usando primers específicos para ech. Como o uso da vanilina como sabor aumentou tremendamente, a bioprodução da vanilina deve ser focada.

Identification by molecular techniques of halophilic bacteria producing important enzymes from pristine area in Campeche, Mexico / Identificação por técnicas moleculares de bactérias halofílicas que produzem enzimas importantes em área intocada de Campeche, México

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)

Evaluation of antibacterial activity of vitamin C against human bacterial pathogens / Avaliação da atividade antibacteriana da vitamina C contra patógenos bacterianos humanos

Now a day’s multidrug resistance phenomenon has become the main cause for concern and there has been an inadequate achievement in the development of novel antibiotics to treat the bacterial infections. Therefore, there is an unmet need to search for novel adjuvant. Vitamin C is one such promising adjuvant. The present study was aimed to elucidate the antibacterial effect of vitamin C at various temperatures (4°C, 37°C and 50°C) and pH (3, 8, and 11), against Gram-positive and Gram-negative bacteria at various concentrations (5-20 mg/ml) through agar well diffusion method. Growth inhibition of all bacterial strains by vitamin C was concentration-dependent. Vitamin C significantly inhibited the growth of Gram-positive bacteria: Bacillus licheniformis (25.3 ± 0.9 mm), Staphylococcus aureus (22.0 ± 0.6 mm), Bacillus subtilis (19.3 ± 0.3 mm) and Gram-negative bacteria: Proteus mirabilis (27.67 ± 0.882 mm), Klebsiella pneumoniae (21.33±0.9 mm), Pseudomonas aeruginosa (18.0 ± 1.5 mm) and Escherichia coli (18.3 ± 0.3 mm). The stability of vitamin C was observed at various pH values and various temperatures. Vitamin C showed significant antibacterial activity at acidic pH against all bacterial strains. Vitamin C remained the stable at different temperatures. It was concluded that vitamin C is an effective and safe antibacterial agent that can be used in the future as an adjunct treatment option to combat infections in humans.

Agora, a resistência antimicrobiana de um dia em patógenos aos antibióticos tornou-se a principal causa de preocupação e houve uma realização inadequada no desenvolvimento de novos antibióticos para tratar infecções bacterianas. Portanto, há uma necessidade de pesquisar um novo adjuvante, e a vitamina C é um desses adjuvantes promissores. O objetivo do presente estudo foi elucidar o efeito antibacteriano da vitamina C em diferentes temperaturas (4 °C, 37 °C e 50 °C) e pH (3, 8 e 11), contra Gram-positivos e Gram-cepas bacterianas negativas em várias concentrações (5-20 mg / ml) através do método de difusão em ágar bem. A inibição do crescimento de todas as cepas bacterianas pela vitamina C era dependente da concentração. A vitamina C inibiu significativamente o crescimento de bactérias Gram-positivas: Bacillus licheniformis (25,3 ± 0,9 mm), Staphylococcus aureus (22,0 ± 0,6 mm), Bacillus subtilis (19,3 ± 0,3 mm) e bactérias Gram- negativas: Proteus mirabilis (27,7 ± 0,9 mm), Klebsiella pneumoniae (21,3 ± 0,9 mm), Pseudomonas aeruginosa (18,0 ± 1,5 mm) e Escherichia coli (18,3 ± 0,3 mm). A estabilidade da vitamina C foi observada em vários valores de pH e várias temperaturas. A vitamina C mostrou atividade antibacteriana significativa em pH ácido contra todas as cepas bacterianas. A estabilidade da vitamina C permaneceu nas mesmas diferentes temperaturas (4 °C, 37 °C e 50 °C). Concluímos que a vitamina C é um agente antibacteriano eficaz e seguro que pode ser usado no futuro como uma opção de tratamento auxiliar para combater infecções em humanos, pois pode apoiar o sistema imunológico diretamente.

Evaluation of antibacterial activity of vitamin C against human bacterial pathogens / Avaliação da atividade antibacteriana da vitamina C contra patógenos bacterianos humanos

Now a days multidrug resistance phenomenon has become the main cause for concern and there has been an inadequate achievement in the development of novel antibiotics to treat the bacterial infections. Therefore, there is an unmet need to search for novel adjuvant. Vitamin C is one such promising adjuvant. The present study was aimed to elucidate the antibacterial effect of vitamin C at various temperatures (4°C, 37°C and 50°C) and pH (3, 8, and 11), against Gram-positive and Gram-negative bacteria at various concentrations (5-20 mg/ml) through agar well diffusion method. Growth inhibition of all bacterial strains by vitamin C was concentration-dependent. Vitamin C significantly inhibited the growth of Gram-positive bacteria: Bacillus licheniformis (25.3 ± 0.9 mm), Staphylococcus aureus (22.0 ± 0.6 mm), Bacillus subtilis (19.3 ± 0.3 mm) and Gram-negative bacteria: Proteus mirabilis (27.67 ± 0.882 mm), Klebsiella pneumoniae (21.33±0.9 mm), Pseudomonas aeruginosa (18.0 ± 1.5 mm) and Escherichia coli (18.3 ± 0.3 mm). The stability of vitamin C was observed at various pH values and various temperatures. Vitamin C showed significant antibacterial activity at acidic pH against all bacterial strains. Vitamin C remained the stable at different temperatures. It was concluded that vitamin C is an effective and safe antibacterial agent that can be used in the future as an adjunct treatment option to combat infections in humans.(AU)

Agora, a resistência antimicrobiana de um dia em patógenos aos antibióticos tornou-se a principal causa de preocupação e houve uma realização inadequada no desenvolvimento de novos antibióticos para tratar infecções bacterianas. Portanto, há uma necessidade de pesquisar um novo adjuvante, e a vitamina C é um desses adjuvantes promissores. O objetivo do presente estudo foi elucidar o efeito antibacteriano da vitamina C em diferentes temperaturas (4 °C, 37 °C e 50 °C) e pH (3, 8 e 11), contra Gram-positivos e Gram-cepas bacterianas negativas em várias concentrações (5-20 mg / ml) através do método de difusão em ágar bem. A inibição do crescimento de todas as cepas bacterianas pela vitamina C era dependente da concentração. A vitamina C inibiu significativamente o crescimento de bactérias Gram-positivas: Bacillus licheniformis (25,3 ± 0,9 mm), Staphylococcus aureus (22,0 ± 0,6 mm), Bacillus subtilis (19,3 ± 0,3 mm) e bactérias Gram- negativas: Proteus mirabilis (27,7 ± 0,9 mm), Klebsiella pneumoniae (21,3 ± 0,9 mm), Pseudomonas aeruginosa (18,0 ± 1,5 mm) e Escherichia coli (18,3 ± 0,3 mm). A estabilidade da vitamina C foi observada em vários valores de pH e várias temperaturas. A vitamina C mostrou atividade antibacteriana significativa em pH ácido contra todas as cepas bacterianas. A estabilidade da vitamina C permaneceu nas mesmas diferentes temperaturas (4 °C, 37 °C e 50 °C). Concluímos que a vitamina C é um agente antibacteriano eficaz e seguro que pode ser usado no futuro como uma opção de tratamento auxiliar para combater infecções em humanos, pois pode apoiar o sistema imunológico diretamente.(AU)

Inhibition of mycelial growth, conidial germination, and Botrytis cinerea Pers: Fr colonization in begonia with biocompatible products

This study evaluated the effects of potassium and sodium carbonate and bicarbonate, Bacillus subtilis (Cohn, 1872) QST-713, Bacillus pumilus (Meyer & Gottheil, 1901) QST-2808, and crude and roasted coffee oils on the inhibition of mycelial growth and conidial germination in Botrytis cinerea Pers.: Fr and the colonization of begonia (Begonia elatior Hort. ex Steud) leaf discs by B. cinerea inoculated before, simultaneously and after with these alternative products. The assays were carried out using the Baladin begonia cultivar. The inhibition of B. cinerea mycelial growth and conidial germination was proportional to increases in the concentration of all the products. The inhibition of conidial germination was directly proportional to the concentrations of B. pumilus QST-2808 and B. subtilis QST-713. Coffee oils were less efficient in inhibiting germination than the other products. The crude and roasted coffee oils, potassium and sodium carbonates and bicarbonates, and B. pumilus and B. subtilis sprayed 24 h before, simultaneously, or 24 h after pathogen inoculation inhibited the colonization of begonia leaf discs by B. cinerea. The positive results for the suppression of B. cinerea by the alternative products tested herein merit scrutiny. There is a pressing need to evaluate these products in the management of gray mold, as the severity of this disease is usually high under favorable conditions in greenhouses.

Effects of a Novel Protease from Bacillus Subtilis K-5 in Low Protein Corn Distiller Dried Grains with Solubles (cDDGS) Based Diets on Performance and Nutrients Digestibility in Broiler Chickens

This experiment was conducted to evaluate the supplemental effects of a novel protease produced from Bacillus subtilis in low crude protein (CP) corn distiller dried grain with solubles (cDDGS) based diets on growth performance, carcass attributes, nutrients digestibility, blood chemistry, and intestinal histomorphometry of broiler chickens. One hundred and sixty, one-day-old chicks were randomly allotted to one of 4 dietary treatments. Each dietary treatment had four replicates, with 10 birds in each replicate. Two basal diets were formulated for both starter (1-21d) and finisher (22-35d) phase; (PC) a corn soybean meal based diet as per standard recommendations of Ross 308; (NC) 5% cDGGS with 5% reduction in CP with concomitant reduction in essential amino acids (EAAs) compared with PC. The negative control diet was further subdivided into 3 parts. One part was without enzyme supplementation, while the other two parts were supplemented with a novel protease (PROT1) and a commercial protease (PROT2), respectively. The same procedure was adopted for finisher diets. A digestibility assay (32-35d) was carried out using acid insoluble ash (AIA), an external digestibility marker. At the end of 35d, ileal digesta were collected from four birds per experimental unit for nutrient digestibility measurement. Tissue samples of duodenum, jejunum, and ileum were collected for villus height, villus width, crypt depth, and crypt width. Body weight gain (BWG) and feed:gain were improved (p<0.05) with protease supplementation. No effect was observed on carcass parameters. However, CP digestibility, apparent digestibility coefficient for nitrogen (ADCn), nitrogen retention (Nret ), and apparent ileal amino acid digestibility (AIAAD) were improved (p<0.05). However, there was no effect on apparent metabolizable energy (AME) and apparent metabolizable energy corrected for nitrogen (AMEn), blood glucose, total protein and cholesterol (p>0.05) and intestinal integrity (p>0.05). It was concluded that protease enzyme can improve nitrogen and CP digestibility, resulting in improved amino acids availability in low protein diets.(AU)

Bacillus subtilis Bs10 as an efficient inoculant for growth promotion in soybean plants / Bacillus subtilis Bs10 como um inoculante eficiente para a promoção do crescimento de plantas de soja

Currently, food with low levels of pesticides, sustainable agricultural practices and increased crop productivity have gained prominence worldwide. Rhizobacterial inoculants are an alternative to manage large crops that favors sustainable plant growth. Thereby, this study aimed to assess the effect of increasing doses of inoculant based on the rhizobacterium Bacillus subtilis Bs10 compared to the commercial product based on B. subtilis on the development of soybean culture. Two experiments were carried out with two soybean cultivars, M8210 IPRO and M8615 IPRO, assessed at the vegetative and reproductive stages. Doses of B. subtilis Bs10 with 0, 100, 200, 300, 400 mL per 50 kg seeds were inoculated in each experiment, as well as an additional treatment with commercial product based on B. subtilis. Biomass, nodulation, plant height, internodes, number of pods and number of grains of soybean cultivars were assessed. The inoculation of B. subtilis Bs10 significantly (p < 0.05) improved the agronomic characteristics of both soybean cultivars with an increase in shoot and root biomass, nodulation, phosphorus content, and accumulation of nitrogen in the aerial part. The doses of B. subtilis Bs10 between 200 and 350 mL had significant prominence in increasing the variables studied herein.(AU)

Atualmente, alimentos com baixo teor de agrotóxicos, práticas agrícolas sustentáveis e aumento da produtividade das lavouras têm ganhado destaque no mundo. Inoculantes de rizobactérias são uma alternativa no manejo de grandes lavouras, o que favorece o crescimento sustentável das plantas. Assim, este estudo teve como objetivo avaliar o efeito de doses crescentes do inoculante à base de Rhizobacteria Bacillus subtilis Bs10 em comparação ao produto comercial à base de B. subtilis no desenvolvimento da cultura da soja. Dois experimentos foram conduzidos com as cultivares de soja M8210 IPRO e M8615 IPRO e avaliados nas fases vegetativa e reprodutiva. Doses de B. subtilis Bs10 com 0, 100, 200, 300, 400 mL por 50 kg de sementes foram inoculadas em cada experimento, bem como tratamento adicional com produto comercial à base de B. subtilis. Foram avaliadas biomassa, nodulação, altura de planta, entrenós, número de vagens e número de grãos de cultivares de soja. A inoculação de B. subtilis Bs10 melhorou significativamente (p < 0,05) as características agronômicas de ambas as cultivares de soja com aumento na biomassa da parte aérea e radicular, nodulação, teor de fósforo e acúmulo de nitrogênio na parte aérea. As doses de B. subtilis Bs10 entre 200 e 350 mL destacaram-se significativamente no aumento das variáveis estudadas neste trabalho.(AU)

Inhibitory activities of propolis, nisin, melittin and essential oil compounds on Paenibacillus alvei and Bacillus subtilis

Background: Natural products represent important sources of antimicrobial compounds. Propolis and compounds from essential oils comprise good examples of such substances because of their inhibitory effects on bacterial spores, including bee pathogens. Methods: Ethanol extracts of propolis (EEP) from Apis mellifera were prepared using different methods: double ultrasonication, double maceration and maceration associated with ultrasonication. Together with the antimicrobial peptides nisin and melittin, and compounds present in the essential oils of clove (Syzygium aromaticum) and cinnamon (Cinnamomum zeylanicum), assays were carried out on one Bacillus subtilis isolate and Paenibacillus alvei (ATCC 6344) against vegetative and sporulated forms, using the resazurin microtiter assay. Synergism with all the antimicrobials in association with tetracycline was verified by the time-kill curve method. Potassium and phosphate efflux, release of proteins and nucleic acids were investigated. Results: EEPs showed the same MIC, 156.25 µg/mL against B. subtilis and 78.12 µg/mL against P. alvei. The peptides showed better activities against B. subtilis (MIC of 12 µg/ mL for melittin and 37.50 µg/mL for nisin). Antimicrobials showed similar inhibitory effects, but cinnamaldehyde (39.06 µg/mL) showed the best action against P. alvei. Melittin and nisin showed the greatest capacity to reduce spores, regarding B. subtilis there was a 100% reduction at 6.25 and 0.78 µg/mL, respectively. Concerning P. alvei, the reduction was 93 and 98% at concentrations of 80 µg/mL of melittin and 15 µg/ mL of nisin. EEPs showed the highest effects on the protein release against B. subtilis and P. alvei. Nucleic acid release, phosphate and potassium efflux assays indicated bacterial cell membrane damage. Synergism between antimicrobials and tetracycline was demonstrated against both bacteria. Conclusion: All antimicrobials tested showed antibacterial activities against vegetative and sporulated forms of P. alvei and B. subtilis, especially nisin and melittin. Synergism with tetracycline and damage on bacterial cell membrane also occurred.(AU)

In vitro antibacterial activities of silver nanoparticles synthesised using the seed extracts of three varieties of Phoenix dactylifera / Atividades antibacterianas in vitro de nanopartículas de prata sintetizadas usando extratos de sementes de três variedades de Phoenix dactylifera

Green synthesis of silver nanoparticles (AgNPs) is an ecofriendly, cost-effective and promising approach for discovery of novel therapeutics. The aim of the current work was to biogenic synthesize, characterize AgNPs using seed extracts of three economically important varieties of date palm (Iklas, Irziz and Shishi), and assess their anti-pathogenic bacterial activities. AgNPs were synthesised then characterised using electron microscopy and Fourier transform infrared analyses. The bactericidal activities of AgNPs against five different bacterial pathogens, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus and Streptococcus pneumoniae, were determined in vitro. In particular, changes in membrane integrity of virulent bacterial strains in response to AgNPs were investigated. Results of lactate dehydrogenase, alkaline phosphatase activity assays, and measurement of membrane potential revealed that the cytotoxic effects of the AgNPs were mainly centred on the plasma membrane of bacterial cells, leading to loss of its integrity and eventually cell death. In conclusion, green synthesis of AgNPs is an efficient, cost-effective and promising strategy to combat virulent antibiotic-resistant strains.

A síntese verde de nanopartículas de prata (AgNPs) é uma abordagem ecologicamente correta, econômica e promissora para a descoberta de novas terapêuticas. O objetivo do presente trabalho foi sintetizar biogênica, caracterizar AgNPs usando extratos de sementes de três variedades economicamente importantes de tamareira (Iklas, Irziz e Shishi) e avaliar suas atividades bacterianas antipatogênicas. AgNPs foram sintetizados e caracterizados usando microscopia eletrônica e análise de infravermelho por transformada de Fourier. As atividades bactericidas de AgNPs contra cinco diferentes patógenos bacterianos, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Staphylococcus aureus resistente à meticilina e Streptococcus pneumoniae, foram determinadas in vitro. Em particular, foram investigadas alterações na integridade da membrana de cepas bacterianas virulentas em resposta a AgNPs. Os resultados da lactato desidrogenase, dos ensaios da atividade da fosfatase alcalina e da medição do potencial de membrana revelaram que os efeitos citotóxicos dos AgNPs estavam principalmente centrados na membrana plasmática das células bacterianas, levando à perda de sua integridade e, eventualmente, à morte celular. A síntese verde de AgNPs é uma estratégia eficiente, econômica e promissora para combater cepas virulentas resistentes a antibióticos.

In vitro antibacterial activities of silver nanoparticles synthesised using the seed extracts of three varieties of Phoenix dactylifera / Atividades antibacterianas in vitro de nanopartículas de prata sintetizadas usando extratos de sementes de três variedades de Phoenix dactylifera

Green synthesis of silver nanoparticles (AgNPs) is an ecofriendly, cost-effective and promising approach for discovery of novel therapeutics. The aim of the current work was to biogenic synthesize, characterize AgNPs using seed extracts of three economically important varieties of date palm (Iklas, Irziz and Shishi), and assess their anti-pathogenic bacterial activities. AgNPs were synthesised then characterised using electron microscopy and Fourier transform infrared analyses. The bactericidal activities of AgNPs against five different bacterial pathogens, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus and Streptococcus pneumoniae, were determined in vitro. In particular, changes in membrane integrity of virulent bacterial strains in response to AgNPs were investigated. Results of lactate dehydrogenase, alkaline phosphatase activity assays, and measurement of membrane potential revealed that the cytotoxic effects of the AgNPs were mainly centred on the plasma membrane of bacterial cells, leading to loss of its integrity and eventually cell death. In conclusion, green synthesis of AgNPs is an efficient, cost-effective and promising strategy to combat virulent antibiotic-resistant strains.(AU)

A síntese verde de nanopartículas de prata (AgNPs) é uma abordagem ecologicamente correta, econômica e promissora para a descoberta de novas terapêuticas. O objetivo do presente trabalho foi sintetizar biogênica, caracterizar AgNPs usando extratos de sementes de três variedades economicamente importantes de tamareira (Iklas, Irziz e Shishi) e avaliar suas atividades bacterianas antipatogênicas. AgNPs foram sintetizados e caracterizados usando microscopia eletrônica e análise de infravermelho por transformada de Fourier. As atividades bactericidas de AgNPs contra cinco diferentes patógenos bacterianos, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Staphylococcus aureus resistente à meticilina e Streptococcus pneumoniae, foram determinadas in vitro. Em particular, foram investigadas alterações na integridade da membrana de cepas bacterianas virulentas em resposta a AgNPs. Os resultados da lactato desidrogenase, dos ensaios da atividade da fosfatase alcalina e da medição do potencial de membrana revelaram que os efeitos citotóxicos dos AgNPs estavam principalmente centrados na membrana plasmática das células bacterianas, levando à perda de sua integridade e, eventualmente, à morte celular. A síntese verde de AgNPs é uma estratégia eficiente, econômica e promissora para combater cepas virulentas resistentes a antibióticos.(AU)

Evaluation of the Effect of Bacillus Subtilis and Pediococcus Acidilactici Mix on Serum Biochemistry, Growth Promotation of Body and Visceral Organs in Lohmann Brown Chicks

Recently the use of antibiotic growth promoter (AGPs) in poultry feed is banned in China, leading to the increasing demand for AGPs substitutes. Probiotics have been considered as a potential substitute. The purpose of this study was to evaluate the effects of probiotic on serum biochemistry, and growth promotion of body weight and visceral organs and in Lohmann Brown chicks aged 0 to 9 weeks. Five hundred and forty 1-day-old male chicks were randomly divided into three groups, with six replicates and 30 chicks in each replicate. The experiment was carried out over 70 days. Dietary treatments were: (1) basal diet alone (control group); (2) basal diet containing 0.1% probiotics (probiotic group); and (3) basal diet containing 0.01% zinc bacitracin in the feed (antibiotic group). The body weight (BW) of probiotic group was significantly higher than that of the control group during the whole trial period (p 0.05). ADG (0~70 d) in the probiotic group and the antibiotic group was higher than that in the control group (p 0.05). The Oliver weight and serum total protein (TP) in the probiotic group was higher than that in the control group on the 63rd day (p 0.05). The length of the duodenum, the weight of the spleen, duodenum and Jejunum in both the probiotic and antibiotic groups were higher than those in the control group (p 0.05). The ileum weight in the probiotic group was significantly higher than those in the control group (p 0.05). The ileum length in the probiotic group was significantly longer than that in both the antibiotic and control groups (p 0.05). Probiotic mix with Bacillus subtilis and Pediococcus acidilactici play a similar role in promoting growth of body and visceral organs, and it is a promising growth promoter for Lohmann Brown chicks (0 to 9 weeks).(AU)

Evaluation of the Effect of Bacillus Subtilis and Pediococcus Acidilactici Mix on Serum Biochemistry, Growth Promotation of Body and Visceral Organs in Lohmann Brown Chicks

Recently the use of antibiotic growth promoter (AGPs) in poultry feed is banned in China, leading to the increasing demand for AGPs substitutes. Probiotics have been considered as a potential substitute. The purpose of this study was to evaluate the effects of probiotic on serum biochemistry, and growth promotion of body weight and visceral organs and in Lohmann Brown chicks aged 0 to 9 weeks. Five hundred and forty 1-day-old male chicks were randomly divided into three groups, with six replicates and 30 chicks in each replicate. The experiment was carried out over 70 days. Dietary treatments were: (1) basal diet alone (control group); (2) basal diet containing 0.1% probiotics (probiotic group); and (3) basal diet containing 0.01% zinc bacitracin in the feed (antibiotic group). The body weight (BW) of probiotic group was significantly higher than that of the control group during the whole trial period (p 0.05). ADG (0~70 d) in the probiotic group and the antibiotic group was higher than that in the control group (p 0.05). The Oliver weight and serum total protein (TP) in the probiotic group was higher than that in the control group on the 63rd day (p 0.05). The length of the duodenum, the weight of the spleen, duodenum and Jejunum in both the probiotic and antibiotic groups were higher than those in the control group (p 0.05). The ileum weight in the probiotic group was significantly higher than those in the control group (p 0.05). The ileum length in the probiotic group was significantly longer than that in both the antibiotic and control groups (p 0.05). Probiotic mix with Bacillus subtilis and Pediococcus acidilactici play a similar role in promoting growth of body and visceral organs, and it is a promising growth promoter for Lohmann Brown chicks (0 to 9 weeks).

Probiotic Bacillus subtilis and Lactobacillus plantarum in diet of Nile tilapia / Probiótico Bacillus subtilis e Lactobacillus plantarum na dieta de tilápia-do-nilo

The aim of this study was to evaluate the effects of a probiotic, composed of Bacillus subtilis and Lactobacillus plantarum in Nile tilapia fry during the sex reversal phase under stress conditions caused by high stocking density. This experiment was conducted in the Fisheries Institute of São Paulo. The experiment design was completely randomized with four treatments: 1) probiotic added feed, 2) probiotic added to water, 3) probiotic added to feed and water and 4) control diet; with three replicates. The variables analyzed were: final weight, total length, specific growth rate, survival, intestinal microbiology and gene expression of TNF-α and HSP-70. The results of the zootechnical performance of growth and gene expression did not show significant differences between treatments in the parameters evaluated (P>0.05). In the intestinal tract of fry raised in water with added probiotic, log(10) CFU (7.72 ± 0.51) count of Bacillus spp. was higher than with other treatments which themselves did not differ significantly. It was concluded that the addition of a probiotic of Bacillus subtilis and Lactobacillus plantarum in the feed or water of Nile tilapia fry during the sex reversal phase did not affect the zootechnical performance of growth or expression the genes studied, but modified the intestinal microbiota.

Objetivou-se com este trabalho avaliar os efeitos da administração do probiótico composto de Bacillus subtilis e Lactobacillus plantarum em pós-larvas de tilápia-do-nilo, durante a fase de reversão sexual, em condições de estresse pela alta densidade de estocagem. O experimento foi realizado no Instituto de Pesca de São Paulo, e foi inteiramente casualizado com quatro tratamentos e cinco repetições. Sendo: 1) probiótico na ração; 2) probiótico na água; 3) probiótico na ração e água; 4) controle. As variáveis analisadas foram: peso final, comprimento total, taxa de crescimento específico, sobrevivência, microbiologia do trato intestinal e expressão dos genes TNF-α e HSP-70. Os resultados de desempenho zootécnico de crescimento e expressão gênica não apresentaram diferenças significativas entre os tratamentos nos parâmetros avaliados (P>0,05). No trato intestinal dos alevinos do tratamento com adição de probiótico na água, foi observado log(10) (7,72±0,51) UFC, superior à contagem de Bacillus spp. em comparação aos demais tratamentos, e estes não apresentaram diferenças estatísticas entre si. Conclui-se que a adição dos probióticos Bacillus subtilis e Lactobacillus plantarum, na dieta ou na água de criação das pós-larvas de tilápia-do-nilo, durante fase de reversão sexual não causaram melhora no desempenho zootécnico de crescimento e expressão gênica, mas modificou a composição bacteriana intestinal.

Probiotic Bacillus subtilis and Lactobacillus plantarum in diet of Nile tilapia / Probiótico Bacillus subtilis e Lactobacillus plantarum na dieta de tilápia-do-nilo

The aim of this study was to evaluate the effects of a probiotic, composed of Bacillus subtilis and Lactobacillus plantarum in Nile tilapia fry during the sex reversal phase under stress conditions caused by high stocking density. This experiment was conducted in the Fisheries Institute of São Paulo. The experiment design was completely randomized with four treatments: 1) probiotic added feed, 2) probiotic added to water, 3) probiotic added to feed and water and 4) control diet; with three replicates. The variables analyzed were: final weight, total length, specific growth rate, survival, intestinal microbiology and gene expression of TNF-α and HSP-70. The results of the zootechnical performance of growth and gene expression did not show significant differences between treatments in the parameters evaluated (P>0.05). In the intestinal tract of fry raised in water with added probiotic, log(10) CFU (7.72 ± 0.51) count of Bacillus spp. was higher than with other treatments which themselves did not differ significantly. It was concluded that the addition of a probiotic of Bacillus subtilis and Lactobacillus plantarum in the feed or water of Nile tilapia fry during the sex reversal phase did not affect the zootechnical performance of growth or expression the genes studied, but modified the intestinal microbiota.(AU)

Objetivou-se com este trabalho avaliar os efeitos da administração do probiótico composto de Bacillus subtilis e Lactobacillus plantarum em pós-larvas de tilápia-do-nilo, durante a fase de reversão sexual, em condições de estresse pela alta densidade de estocagem. O experimento foi realizado no Instituto de Pesca de São Paulo, e foi inteiramente casualizado com quatro tratamentos e cinco repetições. Sendo: 1) probiótico na ração; 2) probiótico na água; 3) probiótico na ração e água; 4) controle. As variáveis analisadas foram: peso final, comprimento total, taxa de crescimento específico, sobrevivência, microbiologia do trato intestinal e expressão dos genes TNF-α e HSP-70. Os resultados de desempenho zootécnico de crescimento e expressão gênica não apresentaram diferenças significativas entre os tratamentos nos parâmetros avaliados (P>0,05). No trato intestinal dos alevinos do tratamento com adição de probiótico na água, foi observado log(10) (7,72±0,51) UFC, superior à contagem de Bacillus spp. em comparação aos demais tratamentos, e estes não apresentaram diferenças estatísticas entre si. Conclui-se que a adição dos probióticos Bacillus subtilis e Lactobacillus plantarum, na dieta ou na água de criação das pós-larvas de tilápia-do-nilo, durante fase de reversão sexual não causaram melhora no desempenho zootécnico de crescimento e expressão gênica, mas modificou a composição bacteriana intestinal.(AU)

Bacillus subtilis improves maize tolerance to salinity / Bacillus subtilis melhora a tolerância do milho a salinidade

The aim of this study was to evaluate the biochemical responses of maize, under saline stress, inoculated with Bacillus subtilis. Four levels of salinity were assessed: 0mM, 50mM, 100mM, and 200mM of sodium chloride (NaCl). Saline conditions influenced negatively maize growth. However, the inoculation of B. subtilis improved the plant growth at highest level of NaCl. Chlorophyll content decreased while proline increased in inoculated plants submitted to highest salt levels. Also, B. subtilis increased the relative water content in leaves. B. subtilis improves the plant growth under salinity and ameliorates the biochemical damages in maize.(AU)

O objetivo do estudo foi avaliar a resposta bioquímica do milho, sob stresse salino, inoculado com Bacillus subtilis. Quatro níveis de salinidade foram avaliados: 0mM, 50mM, 100mM e 200mM de cloreto de sódio (NaCl). Condições salinas influenciaram negativamente o crescimento do milho. Entretanto, a inoculação com B. subtilis melhorou o crescimento das plantas no maior nível de NaCl. O teor de clorofila decresceu enquanto que a prolina aumentou em plantas submetidas aos níveis salinos e inoculadas com B. subtilis. B. subtilis também aumentou o conteúdo de agua foliar. A inoculação com B. subtilis promove melhor crescimento das plantas sob salinidade e atenua os danos bioquímicos no milho.(AU)