Identification of antarctic soil bacteria exhibiting antiproliferative activity against a colon cancer cell line / Identificación de bacterias de suelo antártico que presentan actividad antiproliferativa sobre una línea celular de cáncer de colon

SUMMARY: Cancer is the second leading cause of death in the world and colorectal cancer is the only cancer that has shown a sustained increase in mortality in the last decade. In the search for new chemotherapeutic agents against cancer, extremophilic microorganisms have shown to be a potential source to obtain molecules of natural origin and with selective cytotoxic action towards cancer cells. In this work we analyzed the ability of a collection of Antarctic soil bacteria, isolated on Collins Glacier from the rhizosphere of Deschampsia antarctica Desv plant, to secrete molecules capable of inhibiting cell proliferation of a colorectal cancer tumor line. Our results demonstrated that culture supernatants from the Antarctic bacteria K2I17 and MI12 decreased the viability of LoVo cells, a colorectal adenocarcinoma cell line. Phenotypic and genotypic characterization of the Antarctic bacteria showed that they were taxonomically related and nucleotide identity analysis based on the 16S rRNA gene sequence identified the bacterium K2I17 as a species belonging to the genus Bacillus.

El cáncer es la segunda causa de muerte en el mundo y el cáncer colorrectal es el único que presenta un aumento sostenido de la mortalidad en la última década. En la búsqueda de nuevos agentes quimioterapeúticos contra el cáncer, se ha propuesto a los microorganismos extremófilos como una fuente potencial para obtener moléculas de origen natural y con acción citotóxica selectiva hacia las células cancerígenas. En este trabajo analizamos la capacidad de una colección de bacterias de suelo antártico, aisladas en el glaciar Collins desde rizosfera de la planta de Deschampsia antarctica Desv, de secretar moléculas capaces de inhibir la proliferación celular de una línea tumoral de cáncer colorrectal. Nuestros resultados demostraron que los sobrenadantes de cultivo de las bacterias antárticas K2I17 y MI12 disminuyeron la viabilidad de la línea celular de adenocarcinoma colorrectal LoVo, en un ensayo de reducción metabólica de MTT. La caracterización fenotípica y genotípica de las bacterias antárticas, demostró que estaban relacionadas taxonómicamente y el análisis de la identidad nucleotídica en base a la secuencia del gen ARNr 16S identificó a la bacteria K2I17 como una especie perteneciente al género Bacillus.

Biodegradation of petroleum by bacteria isolated from fishes of Indian Ocean / Biodegradação do petróleo por bactérias isoladas de peixes do oceano Índico

In this study, oil degrading bacteria discovered from fish living near the oil ports at Karachi in Pakistan were characterized. The bacteria isolated from skin, gills, and gut in fish could consume crude oil as a source of carbon and energy. Total 36 isolates were tested using Nutrient Agar (NA) and MSA media with different crude oil concentrations (0.2%, 0.5%, 0.7%, 1%, 2%, and 5%) and 4 out of 36 isolates (two Gram positive and two Gram negative bacteria) were selected for further identification. 16S rRNA gene sequencing revealed that the isolates are related to Bacillus velezensis, Bacillus flexus, Pseudomonas brenneri and Pseudomonas azotoforman. Oil degrading potential of these bacteria was characterized by GC-MS analysis of degradation of oil components in crude oil as well as engine oil. We found that one (2, 6, 10, 14-Tetramethylpentadecane) out of 42 components in the crude oil was fully eliminated and the other oil components were reduced. In addition, 26 out of 42 oil components in the engine oil, were fully eliminated and the rest were amended. Taken together, these studies identify that B. velezensis, B. flexus, P. brenneri and P. azotoforman have high oil degrading potential, which may be useful for degradation of oil pollutants and other commercial applications.

Neste estudo, bactérias degradadoras de óleo descobertas em peixes que vivem perto dos portos de petróleo em Karachi, no Paquistão, foram caracterizadas. As bactérias isoladas da pele, guelras e intestinos dos peixes podem consumir petróleo bruto como fonte de carbono e energia. No total, 36 isolados foram testados usando Agar Nutriente (NA) e meio MSA com diferentes concentrações de óleo bruto (0,2%, 0,5%, 0,7%, 1%, 2% e 5%) e 4 de 36 isolados (dois Gram positivos e duas bactérias Gram negativas) foram selecionadas para posterior identificação. O sequenciamento do gene 16S rRNA revelou que os isolados estão relacionados a Bacillus velezensis, Bacillus flexus, Pseudomonas brenneri e Pseudomonas azotoforman. O potencial de degradação do óleo dessas bactérias foi caracterizado pela análise de GC-MS da degradação dos componentes do óleo no óleo cru, bem como no óleo do motor. Descobrimos que um (2, 6, 10, 14-tetrametilpentadecano) de 42 componentes do óleo cru foi totalmente eliminado e os outros componentes do óleo foram reduzidos. Além disso, 26 dos 42 componentes do óleo do motor foram totalmente eliminados e o restante corrigido. Juntos, esses estudos identificam que B. velezensis, B. flexus, P. brenneri e P. azotoforman têm alto potencial de degradação de óleo, o que pode ser útil para a degradação de poluentes de óleo e outras aplicações comerciais.

Screening and Characterization of Bacillus Strains Producing Highly Thermostable Amylase from Various Hot Springs of Algeria

HIGHLIGHTS Screening extremophile Bacillus strains from various Hot Springs Characterization Of Bacillus Strains Producing Highly Thermostable Amylase Genetic identification of the best strains

Abstract Currently thermostable Amylase represents a broad biotechnological interest and desired by a various industries. In this study, forty-six bacterial strains belonging to the genus Bacillus were isolated from various hot springs in the North West of Algeria based on their ability to degrade starch and produce amylase in Starch Agar medium. The majority of isolates showed a positive amylolytic activity. In order to select the most thermostables amylase the effect of temperature on enzymes was estimated, therefore the study of amylase thermostability was culminated by the selection of Four Strains having an interesting optimum of activity and range of stability, reaching 75 °C for the strains HBH1-2, HBH1-3, HBH3-1and 85 °C for the strain HC-2, This indicates that the Enzyme produced by retained strains have optimum activity at high temperature. The identity of the selected strains was established on the basis of the morphological, biochemical characteristics and phylogenetic position as determined by 16S Ribosomal DNA gene sequencing. The whole strains belonged to the genus Bacillus and their phylogeny were also reported in this study.

Isolation and Characterization of Alkaline Pectinase Productive Bacillus tropicus from Fruit and Vegetable Waste Dump Soil

Abstract Alkaline pectinase is the utmost significant industrial enzyme of the bioscouring process. By considering bio scouring of cotton, 30 microbial isolates from fruit and vegetable waste rich dump soil of Solang Valley and Vasishta (Manali, Himachal Pradesh, India) were isolated and screened for the alkaline pectinase production in the current research work. Only four isolates P3, P16, P21, and P27 were capable to produce extracellular alkaline pectinase at pH 9. Further by applying submerged fermentation, the alkaline pectinase production was quantitatively screened. The most efficient isolate was P3 identified as Bacillus tropicus, based on morphological, biochemical, and molecular characterization. Molecular characteristics confirmed by 16S rDNA sequence analysis. The nucleotide sequence of the isolate was novel with a 97% similarity index and submitted to the GenBank with accession number MK332379. The Bacillus strain selected was active at broad pH range from 8-10.5 and a temperature range from 25-50 oC. Optimum pH and temperature observed were 9 and 37 oC respectively and can be suitably used for the bio scouring process for the pretreatment of the fabrics.

Bacteria isolated from the lower respiratory tract of sheep and their relationship to clinical signs of sheep respiratory disease / Bactérias detectadas no trato respiratório inferior de ovinos e a relação com as manifestações clínicas da doença respiratória ovina

Respiratory diseases are among the most important diseases in sheep flocks. Herein was studied the bacterial etiology of respiratory disease and the clinical signs of 99 female and male sheep breed in the states of São Paulo (SP) and Rio de Janeiro (RJ), Brazil. After physical examination of animals, tracheobronchial flushing samples were obtained. The usual bacteria and Mycoplasma spp. were searched, as well as their association with the clinical status and clinical signs of sheep with respiratory disease. The main observed signs were: tachypnea (75%), increase of rectal temperature (09.4%), mucopurulent/purulent nasal discharge (21.9%), cough (25%), dyspnea (31.2%), changes of lung sounds at auscultation (87.5%) and chest percussion (28.1%) in pneumonic sheep. Non-fermenting gram-negative bacteria and Bacillus sp. were the most isolated bacteria. Microorganisms of the Mollicutes class were molecularly (PCR) detected in 33.3% of the animals. In addition, the specific detection of M. mycoides subsp. capri was described for the first time in sheep from the state of São Paulo, Brazil.(AU)

A doença respiratória é uma das doenças mais importantes em rebanhos ovinos. Esta pesquisa teve como objetivo determinar a etiologia bacteriana da doença respiratória e sua relação com sinais clínicos em ovinos criados nos estados de São Paulo e Rio de Janeiro, Brasil. Noventa e nove ovelhas machos e fêmeas dos Estados de São Paulo (SP) e Rio de Janeiro (RJ) foram estudadas. Após o exame físico, amostras de lavagem traqueobrônquica foram obtidas. A presença de bactérias aeróbias e Mycoplasmaspp. foram estudados, assim como a associação entre os microrganismos e estado clínico e sinais clínicos de doença respiratória em ovinos. As principais manifestações clínicas observadas foram: taquipneia (75%), alta temperatura retal (09,4%), secreção nasal mucopurulenta/purulenta (21,9%), tosse (25%), dispneia (31,2%), sons pulmonares alterados na ausculta (87,5%) e na percussão torácica (28,1%) em ovelhas pneumônicas. Bactérias gram-negativas não fermentadoras e Bacillus sp. foram as bactérias mais isoladas. Microrganismos da classe Mollicutes foram detectados molecularmente (PCR) em 33,3% dos ovinos. Além disso, descreve-se pela primeira vez no estado de São Paulo, Brasil, a detecção do M. mycoides subsp. capri na espécie ovina utilizando a reação de polimerase em cadeia.(AU)

Inducible cellulase production from an organic solvent tolerant Bacillus sp. SV1 and evolutionary divergence of endoglucanase in different species of the genus Bacillus

Abstract Bacteria are important sources of cellulases with various industrial and biotechnological applications. In view of this, a non-hemolytic bacterial strain, tolerant to various environmental pollutants (heavy metals and organic solvents), showing high cellulolytic index (7.89) was isolated from cattle shed soil and identified as Bacillus sp. SV1 (99.27% pairwise similarity with Bacillus korlensis). Extracellular cellulases showed the presence of endoglucanase, total cellulase and β-glucosidase activities. Cellulase production was induced in presence of cellulose (3.3 times CMCase, 2.9 times FPase and 2.1 times β-glucosidase), and enhanced (115.1% CMCase) by low-cost corn steep solids. An in silico investigation of endoglucanase (EC 3.2.1.4) protein sequences of three Bacillus spp. as query, revealed their similarities with members of nine bacterial phyla and to Eukaryota (represented by Arthropoda and Nematoda), and also highlighted of a convergent and divergent evolution from other enzymes of different substrate [(1,3)-linked beta-d-glucans, xylan and chitosan] specificities. Characteristic conserved signature indels were observed among members of Actinobacteria (7 aa insert) and Firmicutes (9 aa insert) that served as a potential tool in support of their relatedness in phylogenetic trees.

Control potential of Meloidogyne javanica and Ditylenchus spp. using fluorescent Pseudomonas and Bacillus spp

ABSTRACT Plant Growth Promoting Rhizobacteria (PGPR) have different mechanisms of action in the development of plants, such as growth promotion, production of phytohormones and antibiotic substances and changes in root exudates. These help to control plant diseases. In order to evaluate the potential of microorganisms in the control of Meloidogyne javanica and Ditylenchus spp., five rhizobacteria isolated from rhizosphere of garlic cultivated in the Curitibanos (SC) region were tested. Hatching chambers were set on Petri dishes, in which were added 10 mL of bacterial suspension and 1 mL of M. javanica eggs suspension, at the rate of 4500, on the filter paper of each chamber. The same procedure was performed with 300 juvenile Ditylenchus spp. The experimental design was completely randomized, with four replications. The evaluations were performed every 72 h for nine days. The antagonized population of nematodes was determined in Peters counting chamber, determining the percentage hatching (for M. javanica) and motility (for Ditylenchus spp). Isolates CBSAL02 and CBSAL05 significantly reduced the hatching of M. javanica eggs (74% and 54.77%, respectively) and the motility of Ditylenchus spp. (55.19% and 53.53%, respectively) in vitro. Isolates were identified as belonging to the genera Pseudomonas (CBSAL05) and Bacillus (CBSAL02).

Evaluation antibacterial and antibiofilm activity of the antimicrobial peptide P34 against Staphylococcus aureus and Enterococcus faecalis

ABSTRACT The adhesion ability of bacteria to abiotic surfaces has important implications in food industries, because these organisms can survive for long periods through the biofilm formation. They can be transferred from one place to another in the industry causing contamination of the food processing environment. In this study, the antibacterial and antibiofilm activities of the antimicrobial peptide P34, characterized as a bacteriocin-like substance (BLS P34) were tested against planktonic and sessile cells of Staphylococcus aureus and Enterococcus faecalis isolated from foods. The BLS P34 showed inhibitory effect against all planktonic cells of E. faecalis. The inhibition of biofilm formation and the eradication of pre-formed biofilm were evaluated with the crystal violet assay and with the reduction of 3-bromide [4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium. The BLS P34 promoted a reduction of percentage of adhered microbial cells on the surface, not being able to perform the complete elimination of biofilm formation. The metabolic activity of S. aureus biofilms decreased considerably between 41-95%. However, E. faecalis cells showed up metabolically stimulated. The BLS P34 has the potential antibiofilm for the species S. aureus. Studies suggest more detailed approaches to a better understanding of the interactions between the antimicrobial and bacterial cells within the biofilm structure.

Assessment of petroleum biodegradation for Bacillus toyonensis by the using redox indicator 2,6 dichlorophenol indophenol / Avaliação da biodegradação do petróleo por Bacillus toyonensis, usando o indicador redox 2,6 diclorofenol indofenol

Petroleum degrading microorganisms have been isolated from different environments with the purpose of being used in bioremediation processes in areas impacted by petroleum spills. The objective of this study was to evaluate the ability of Bacillus toyonensis AM07 strain to metabolize petroleum compounds. The strain was isolated from the effluent dike of the Urucu Petroleum Province, Coari - Amazonas, Brazil. The degrading activity of B. toyonensis was evaluated by the colorimetric method using the redox indicator 2,6-dichlorophenol indophenol (DCPIP). Thus, the microorganism was inoculated into minimal medium with DCPIP, and with petroleum as the sole carbon source. The degradation potential of the microorganism was found by changing the DCPIP staining and absorbance readings 600nm. The results obtained demonstrated that the bacterial strain was able to degrade petroleum by altering the color of the medium from blue to colorless and by reducing the concentration of the indicator in the absorbance readings. B. toyonensis AM07 strain has shown good performance in the petroleum degradation assays and may be used in the future in remediation technologies for hydrocarbon impacted environments.

Microrganismos degradadores de petróleo têm sido isolados de diferentes ambientes com a finalidade de serem utilizados em processos de biorremediação de áreas impactadas com derrames de petróleo. O objetivo deste estudo foi avaliar a capacidade da linhagem de Bacillus toyonensis AM07, isolada do dique de efluente da Província Petrolífera de Urucu, Coari - Amazonas, Brasil, em metabolizar compostos do petróleo. A atividade degradadora do B. toyonensis foi avaliada pelo método colorimétrico, utilizando indicador redox 2,6-diclorofenol indofenol (DCPIP). Assim, o microrganismo foi inoculado em meio mínimo com DCPIP e petróleo como única fonte de carbono. O potencial de degradação do microrganismo foi constatado mediante a mudança de coloração DCPIP e leituras de absorbância 600nm. Os resultados obtidos demonstraram que a cepa bacteriana foi capaz de degradar petróleo, alterando a coloração do meio de azul para incolor e reduzindo a concentração do indicador nas leituras de absorbâncias. A cepa de B. toyonensis AM07 mostrou bom desempenho nos ensaios de degradação do petróleo, podendo ser utilizada, no futuro, em tecnologias de remediação de ambientes impactados por hidrocarbonetos.

Promotion of iron nutrition and growth on peanut by Paenibacillus illinoisensis and Bacillus sp. strains in calcareous soil

ABSTRACT This study aimed to explore the effects of two siderophore-producing bacterial strains on iron absorption and plant growth of peanut in calcareous soil. Two siderophore-producing bacterial strains, namely, YZ29 and DZ13, isolated from the rhizosphere soil of peanut, were identified as Paenibacillus illinoisensis and Bacillus sp., respectively. In potted experiments, YZ29 and DZ13 enhanced root activity, chlorophyll and active iron content in leaves, total nitrogen, phosphorus and potassium accumulation of plants and increased the quality of peanut kernels and plant biomass over control. In the field trial, the inoculated treatments performed better than the controls, and the pod yields of the three treatments inoculated with YZ29, DZ13, and YZ29 + DZ13 (1:1) increased by 37.05%, 13.80% and 13.57%, respectively, compared with the control. Based on terminal restriction fragment length polymorphism analysis, YZ29 and DZ13 improved the bacterial community richness and species diversity of soil surrounding the peanut roots. Therefore, YZ29 and DZ13 can be used as candidate bacterial strains to relieve chlorosis of peanut and promote peanut growth. The present study is the first to explore the effect of siderophores produced by P. illinoisensis on iron absorption.

Evaluation of short-chain-length polyhydroxyalkanoate accumulation in Bacillus aryabhattai

Abstract This study was focused on the polyhydroxybutyrate (PHB) accumulation property of Bacillus aryabhattai isolated from environment. Twenty-four polyhydroxyalkanoate (PHA) producers were screened out from sixty-two environmental bacterial isolates based on Sudan Black B colony staining. Based on their PHA accumulation property, six promising isolates were further screened out. The most productive isolate PHB10 was identified as B. aryabhattai PHB10. The polymer production maxima were 3.264 g/L, 2.181 g/L, 1.47 g/L, 1.742 g/L and 1.786 g/L in glucose, fructose, maltose, starch and glycerol respectively. The bacterial culture reached its stationary and declining phases at 18 h and 21 h respectively and indicated growth-associated PHB production. Nuclear Magnetic Resonance (NMR) spectra confirmed the material as PHB. The material has thermal stability between 30 and 140 °C, melting point at 170 °C and maximum thermal degradation at 287 °C. The molecular weight and poly dispersion index of the polymer were found as 199.7 kDa and 2.67 respectively. The bacterium B. aryabhattai accumulating PHB up to 75% of cell dry mass utilizing various carbon sources is a potential candidate for large scale production of bacterial polyhydroxybutyrate.

Microbiological quality of honey from the Pampas Region (Argentina) throughout the extraction process / Calidad microbiológica de la miel en la Región Pampeana (Argentina) a lo largo del proceso de extracción

The microbiological quality of honey obtained from different processing points and the environmental quality within honey houses were assessed in the Pampas Region (Argentina). Mold and yeast (MY), culturable heterotrophic mesophilic bacteria (CHMB), the number of spore-forming bacteria as well as the presence of Shigella spp., Salmonella spp. and fecal coliforms were evaluated in 163 samples. These samples were taken from eight honey houses. Results showed that 89 samples had ≤10 CFU of MY/g honey, 69 ranged from 10 to 50 CFU/g and two reached 65.5 CFU/g. Eighty one percent of the samples showed ≤30 CFU of CHMB/g honey and only seven samples had between 50 and 54.25 CFU/g. Thirty six honey samples were obtained from drums: in 25 samples (69.4%) CHMB counts were less than ≤30 CFU/g of honey; in 20 samples (55.5%) the values of MY were between 10 and 50 CFU/g honey and total coliforms were only detected in 20 samples. Fecal coliforms, spores of clostridia as well as Salmonella spp. and Shigella spp were not detected and less than 50 spores of Bacillus spp. per g were observed in the honey from drums. Therefore, the microbiological honey quality within the honey houses did not show any sanitary risks. Our results were reported to honey house owners to help them understand the need to reinforce proper honey handling and sanitation practices.

Este estudio evaluó la calidad microbiológica de la miel dentro de varias plantas de extracción de miel y la calidad del medio ambiente de las mismas en la Región Pampeana (Argentina). Se trabajó con 163 muestras de miel provenientes de 8 plantas de extracción. Se cuantificaron hongos y levaduras, bacterias aeróbicas mesófilas, bacterias esporuladas y esporas de clostridios. Asimismo, se determinó la presencia de Salmonella spp., Shigella spp. y coliformes fecales. Los resultados mostraron que por g de miel, 89 muestras tuvieron menos de 10 UFC de hongos y levaduras, 69 tuvieron entre 10 y 50 UFC y 2 alcanzaron 65,5 UFC. Ochenta y uno por ciento de las muestras presentaron menos de 30 UFC de bacterias aeróbicas mesófilas por g de miel mientras que solo 7 tuvieron entre 50 y 54,25 UFC. Se obtuvieron 36 muestras de miel directamente de tambor: los conteos de bacterias aeróbicas mesófilas fueron ≤ 30 UFC/g de miel en 25 muestras (69,4%); los valores de hongos y levaduras estuvieron entre 10 y 50 UFC en 20 muestras (55,5%) y solo se detectaron coliformes totales. No se observaron coliformes fecales, esporas de clostridios así como tampoco Salmonella spp. y Shigella spp. y se obtuvieron menos de 50 esporas de Bacillus spp./g en miel de los tambores. Se concluye que la calidad microbiológica de la miel en las plantas de extracción no presentó riesgo sanitario. Los resultados fueron entregados a los dueños de las mismas como aporte para que valoren la importancia de reforzar la aplicación de buenas prácticas de manejo y saneamiento.

Thermostable chitinase from Cohnella sp. A01: isolation and product optimization

Abstract Twelve bacterial strains isolated from shrimp farming ponds were screened for their growth activity on chitin as the sole carbon source. The highly chitinolytic bacterial strain was detected by qualitative cup plate assay and tentatively identified to be Cohnella sp. A01 based on 16S rDNA sequencing and by matching the key morphological, physiological, and biochemical characteristics. The cultivation of Cohnella sp. A01 in the suitable liquid medium resulted in the production of high levels of enzyme. The colloidal chitin, peptone, and K2HPO4 represented the best carbon, nitrogen, and phosphorus sources, respectively. Enzyme production by Cohnella sp. A01 was optimized by the Taguchi method. Our results demonstrated that inoculation amount and temperature of incubation were the most significant factors influencing chitinase production. From the tested values, the best pH/temperature was obtained at pH 5 and 70 °C, with Km and V max values of chitinase to be 5.6 mg/mL and 0.87 µmol/min, respectively. Ag+, Co2+, iodoacetamide, and iodoacetic acid inhibited the enzyme activity, whereas Mn2+, Cu2+, Tweens (20 and 80), Triton X-100, and EDTA increased the same. In addition, the study of the morphological alteration of chitin treated by enzyme by SEM revealed cracks and pores on the chitin surface, indicating a potential application of this enzyme in several industries.

Aislados de Bacillus provenientes de la rizósfera de cactus incrementan la germinación y la floración en Mammillaria spp. (Cactaceae) / Bacillus isolates from rhizosphere of cacti improve germination and bloom in Mammillaria spp. (Cactaceae)

Las cactáceas son la vegetación característica de las zonas áridas en México, donde las lluvias son escasas, la evapotranspiración es elevada y la fertilidad de los suelos es baja. Las plantas han desarrollado estrategias fisiológicas como la asociación con microorganismos en la zona de la rizósfera para incrementar la captación de nutrientes. En el presente trabajo se obtuvieron 4 aislados bacterianos de la rizósfera de Mammillaria magnimamma y Coryphantha radians, los que fueron nombrados como QAP3, QAP19, QAP22 y QAP24 e identificados genéticamente como pertenecientes al género Bacillus. Estos aislados exhibieron in vitro propiedades bioquímicas como solubilización de fosfatos, producción de ácido indolacético y actividad ACC deaminasa, que se relacionan con la promoción del crecimiento de las plantas. Dicha promoción fue ensayada inoculando semillas de M. magnimamma y evaluando luego algunos parámetros. Se encontró que todos los aislados incrementaron la germinación desde un 17% hasta un 34,3% (con respecto a las semillas testigo sin inocular); el aislado QAP24 fue el que presentó el mayor efecto en este sentido y permitió la germinación de todas las semillas viables (84,7%) 3 días antes que en el testigo. La inoculación de este aislado en plantas de Mammillaria zeilmanniana mostró un efecto positivo sobre la floración: en 2 meses dentro del período de un año se detectó un incremento en el número de plantas en floración con respecto a las plantas testigo, de hasta el 31,0% en uno de ellos. Se concluye que los aislados de Bacillus spp. caracterizados poseen potencial para ser empleados en programas de conservación de especies vegetales de zonas áridas.

Cacti are the most representative vegetation of arid zones in Mexico where rainfall is scarce, evapotranspiration is high and soil fertility is low. Plants have developed physiological strategies such as the association with microorganisms in the rhizosphere zone to increase nutrient uptake. In the present work, four bacterial isolates from the rhizosphere of Mammillaria magnimamma and Coryphantha radians were obtained and named as QAP3, QAP19, QAP22 and QAP24, and were genetically identified as belonging to the genus Bacillus, exhibiting in vitro biochemical properties such as phosphate solubilization, indoleacetic acid production and ACC deaminase activity related to plant growth promotion, which was tested by inoculating M. magnimamma seeds. It was found that all isolates increased germination from 17 to 34.3% with respect to the uninoculated control seeds, being QAP24 the one having the greatest effect, accomplishing the germination of viable seeds (84.7%) three days before the control seeds. Subsequently, the inoculation of Mammillari zeilmanniana plants with this isolate showed a positive effect on bloom, registering during two months from a one year period, an increase of up to 31.0% in the number of flowering plants compared to control plants. The characterized Bacillus spp. isolates have potential to be used in conservation programs of plant species from arid zones.

Atividade antibacteriana de diferentes especiarias / Antibacterial activity of different spices

Micro-organismos patogênicos são responsáveis por inúmeras doenças veiculadas por alimentos, causando constante preocupação à indústria alimentícia e consumidores. Além disso, há também a preocupação com os possíveis efeitos adversos causados pelos aditivos químicos usados na conservação dos alimentos. Outro problema relacionado aos micro-organismos patogênicos é sua resistência adquirida frente aos antibióticos comuns. A procura por antimicrobianos naturais, presentes em extratos vegetais, tende a ser uma alternativa bastante interessante para todas estas questões. Dessa forma, o objetivo do presente trabalho foi avaliar a atividade antimicrobiana de especiarias, de forma individual e combinada, sobre algumas bactérias. Foram utilizados extratos aquosos de cinco diferentes especiarias, empregados em disco de papel filtro de 6 mm de diâmetro próprios para antibiograma, colocado em placas de Petri com meios de cultura apropriados, semeados previamente com os seguintes micro-organismos: Bacillus cereus, Bacillus subtilis, Salmonella Typhimurium, Samonella Enteritidis e Staphylococcus aureus, posteriormente incubadas à 35ºC/ 24 ­ 48 horas. Através dos resultados obtidos, concluiu-se que o extrato aquoso de sálvia apresentou atividade antimicrobiana significativa sobre S. Typhimurium (halo de 12 mm), o extrato combinado de sálvia e alho apresentou resultado significativo sobre B. cereus e S. aureus (halos de 10mm), este ainda foi inibido significativamente pelos extratos combinados de sálvia e urucum, sálvia e louro, sálvia e gengibre (halos de 10mm).

Pathogenic micro-organisms are responsible for numerous diseases transmitted by foods, causing constant concern to the provision industry and consumers. Besides, there is also the concern with the possible adverse effects caused by the chemical addictive used in the conservation of foods. Another problem related to the pathogenic micro-organisms is about their resistance acquired to the common antibiotics. The search for natural antimicrobials, presents in vegetable extracts, tends to be a quite interesting alternative for all these subjects. In that way, the objective of the present work was to evaluate the antimicrobial activity of spices, in an individual and combined way, on some bacteria. Were used aqueous extracts of five different spices, inserted in paper filter disks of 6 mm diameter own for antibiogram, placed in Petri dishes with appropriate culture means, previously seeded with the following personal micro-organisms: Bacillus cereus, Bacillus subtilis, Salmonella Typhimurium, Samonella Enteritidis and Staphylococcus aureus, subsequently incubated at 35º C/ 24-48 hours. Through the results obtained, it was concluded that the aqueous extract of sage presented significant antimicrobial activity on S. Typhimurium (inhibition zone 12 mm), the combined extract of sage and garlic presented significant result on B. cereus and S. aureus (inhibition zones 10 mm), this still was inhibited significantly by combined extracts of sage and urucum, sage and blond, sage and ginger (inhibition zones 10 mm).

A new alkalophilic isolate of Bacillus as a producer of cyclodextrin glycosyltransferase using cassava flour

Abstract Cyclodextrin glycosyltransferase (CGTase) catalyzes the conversion of starch into non-reducing cyclic sugars, cyclodextrins, which have several industrial applications. This study aimed to establish optimal culture conditions for β-CGTase production by Bacillus sp. SM-02, isolated from soil of cassava industries waste water lake. The optimization was performed by Central Composite Design (CCD) 2, using cassava flour and corn steep liquor as substrates. The maximum production of 1087.9 U mL−1 was obtained with 25.0 g L−1 of cassava flour and 3.5 g L−1 of corn steep after 72 h by submerged fermentation. The enzyme showed optimum activity at pH 5.0 and temperature 55 °C, and maintained thermal stability at 55 °C for 3 h. The enzymatic activity was stimulated in the presence of Mg+2, Ca+2, EDTA, K+, Ba+2 and Na+ and inhibited in the presence of Hg+2, Cu+2, Fe+2 and Zn+2. The results showed that Bacillus sp. SM-02 have good potential for β-CGTase production.

Bacterial treatment of alkaline cement kiln dust using Bacillus halodurans strain KG1

Abstract This study was conducted to isolate an acid-producing, alkaliphilic bacterium to reduce the alkalinity of cement industry waste (cement kiln dust). Gram-positive isolate KG1 grew well at pH values of 6–12, temperatures of 28–50 °C, and NaCl concentrations of 0–16% and thus was further screened for its potential to reduce the pH of an alkaline medium. Phenotypic characteristics of the KG1 isolate were consistent with those of the genus Bacillus, and the highest level of 16S rRNA gene sequence similarity was found with Bacillus halodurans strain DSM 497 (94.7%). On the basis of its phenotypic characteristics and genotypic distinctiveness from other phylogenetic neighbors belonging to alkaliphilic Bacillus species, the isolated strain was designated B. halodurans strain KG1, with GenBank accession number JQ307184 (= NCIM 5439). Isolate KG1 reduced the alkalinity (by 83.64%) and the chloride content (by 86.96%) of cement kiln dust and showed a potential to be used in the cement industry for a variety of applications.

Isolamento microbiológico do canal auditivo de cães saudáveis e com otite externa na região metropolitana de Recife, Pernambuco / Microbiological isolation from the ear canal of healthy dogs and with otitis externa in the metropolitan region of Recife, Pernambuco

Otite externa (OE) é o termo utilizado para definir a inflamação do conduto auditivo externo; esta doença possui diversas etiologias, ocorre em várias espécies e é particularmente frequente em cães. Os microrganismos da microbiota residente comumente estão envolvidos na etiopatogenia da OE, sendo apontados como agentes perpetuadores da doença. O objetivo deste estudo foi investigar o perfil microbiológico de cães com conduto auditivo saudável e com otite na região metropolitana do Recife. Com o auxílio de suabes estéreis foram coletadas amostras das orelhas direita e esquerda de 41 cães, sendo 11 com OE e 30 sem OE. Foi realizado o isolamento bacteriano e fúngico das amostras cultivadas; observou-se positividade em 80% dos cães com orelhas saudáveis e presença de mais de um microrganismo em 38 amostras (63,3%); já nos cães com OE, a positividade foi 95,3%, com infecção polimicrobiana em 77,3% das amostras. No que se refere aos gêneros bacterianos, o perfil de isolamento microbiológico foi idêntico entre os cães otopatas e sadios. Os microrganismos isolados foram Staphylococcus sp., Micrococcus, Bacillus sp., Streptococcus sp. e Malassezia sp.

Otitis externa (OE) is the term used to describe inflammation of the external ear canal. This disease has many etiologies, occurs in several species and is particularly common in dogs. The resident microbiota microorganisms are commonly involved in the OE etiopathogenesis, being frequently appointed as perpetuator agents. The aim of this study was to investigate the microbiological profile of dogs with healthy ears and of others with otitis in the metropolitan region of Recife, Pernambuco, Brazil. With the aid of sterile swabs, samples of right and left ear of 41 dogs, 11 with and 30 without OE, were collected. Bacterial and fungal isolation was performed with cultured samples; positivity was observed in 80% of animals with healthy ears, with the presence of more than one microrganism in 38 samples (63.3%), whereas in dogs with OE, the positivity was 95.3% with polymicrobial infection in 77.3% samples. With regard to the genus, the microbiological profile was identical between healthy and diseased dogs. The microrganisms isolated were Staphylococcus sp., Micrococcus, Bacillus sp., Streptococcus sp. and Malassezia sp.

Antibiotic susceptibility profile of bacilli isolated from the skin of healthy humans

Abstract In the present work, twelve bacilli were isolated from four different regions of human skin from Bela population of Nagpur district, India. The isolated bacilli were identified by their morphological, cultural and biochemical characteristics. Seven isolates were Gram negative rods, out of which five were belong to genus Pseudomonas. Three among the five Gram positive isolates were identified as Dermabactor and the remaining two Bacillus. Their antimicrobial susceptibility profile was determined by Kirby-Bauer disc diffusion method. The isolates showed resistance to several currently used broad-spectrum antibiotics. The Dermabactor genus was resistant to vancomycin, although it was earlier reported to be susceptible. Imipenem was found to be the most effective antibiotic for Pseudomonas while nalidixic acid, ampicillin and tetracycline were ineffective. Isolates of Bacillus displayed resistance to the extended spectrum antibiotics cephalosporin and ceftazidime. Imipenem, carbenicillin and ticarcillin were found to be the most effective antibiotics as all the investigated isolates were susceptible to them. Antibiotic resistance may be due to the overuse or misuse of antibiotics during the treatment, or following constant exposure to antibiotic-containing cosmetic formulations.