scholarly journals CAPACIDAD DE ADHESIÓN A MOCO DE CORAL DE BACTERIAS AISLADAS DE Pocillopora sp. Y Porites panamensis DEL SUROESTE DEL GOLFO DE CALIFORNIA

2019 ◽  
Vol 34 (1) ◽  
pp. 17
Author(s):  
Irán Suárez González ◽  
Oscar Piña Juarez ◽  
Maurilia Rojas Contreras ◽  
Marco Antonio Cadena Roa ◽  
Ricardo Vázquez Juárez

El estudio de la microbiota en corales es de fundamental importancia para un mejor entendimiento de los procesos que determinan su asociación con el holobionte, sin embargo, aún se conoce poco acerca de los mecanismos básicos de dicha asociación. En esta investigación el objetivo fue aislar a partir de corales sin signos aparentes de enfermedad, las bacterias predominantes de la comunidad, determinar su capacidad de adhesión al moco producido por Pocillopora sp. e identificarlas molecularmente. Se recolectaron corales de los géneros Pocillopora sp. y P. panamensis, se cuantificó la población de cuatro grupos de microorganismos (expresados como Log de UFC g-1): bacterias mesófilas aerobias (4.7 - 6.4), bacterias ácido lácticas (˂1.0-5.8), bacterias del género Vibrio (˂1.0-4.5), así como hongos y levaduras (˂1.0-3.6). Se aislaron 156 cepas bacterianas del holobionte homogeneizado y se seleccionaron aquellas con mayor crecimiento a las 24 h para el ensayo de adhesión, que consistió en 25 cepas de Pocillopora sp. y 27 de Porites panamensis. El ensayo de adhesión al extracto crudo de moco de Pocillopora sp., marcado enzimáticamente con HRP mostró que el 82 % de las cepas se adhieren. Se extrajo ADN de todas las cepas, sin embargo, con los oligonucleótidos universales utilizados se obtuvieron productos de PCR solo de 32. Se identificaron molecularmente 14 de Pocillopora sp. y 18 de P. panamensis con base en la secuenciación y análisis del gen 16S DNAr. Las cepas identificadas correspondieron a 17 especies, donde predominó el género Bacillus, con 64 % en Pocillopora sp. y 44 % en P. panamensis. Las especies de bacterias que comparten estos corales son B. subtilis y Staphylococcus hominis. Se sugiere que las especies identificadas adherentes tienen la capacidad de colonizar el moco del coral, son comensales y potencialmente benéficas, debido a que fueron aisladas de corales aparentemente sanos. Adhesion ability to coral mucus of isolated bacteria from Pocillopora sp. and Porites panamensis of California Gulf southeast ABSTRACT. The study of coral microbiota is of fundamental importance for a better understanding of the processes that determine its association with the holobiont, however, little is known about the basic mechanisms of this association. In this research, the objective was to isolate from corals without apparent signs of disease, the predominant bacteria of the community, determine their ability to adhere to the mucus produced by Pocillopora sp. and identify them molecularly. Corals of the genera Pocillopora sp. and Porites panamensis were recollected, the population of four groups of microorganisms (expressed as Log of CFU g-1) was quantified. Results indicated aerobic mesophilic bacteria (4.7 - 6.4), lactic acid bacteria (˂1.0-5.8), bacteria of the Vibrio genus (˂ 1.0-4.5), as well as fungi and yeasts (˂1.0-3.6). 156 bacterial strains of the homogenized holobiont were isolated and those with the highest growth at 24 h were selected for the adhesion test, which consisted of 25 strains of Pocillopora sp. and 27 of P. panamensis. The adhesion test to the enzymatically labeled with HRP crude mucus extract of Pocillopora sp., showed that 82% of the strains adhere. DNA was extracted from all strains, however, with the universal oligonucleotides used, only 32 PCR products were obtained. 14 strains from Pocillopora sp. and 18 from P. panamensis were molecularly identified based on the sequencing and analysis of the 16S DNAr gene. The strains identified corresponded to 17 species, where the genus Bacillus predominated, with 64% in Pocillopora sp. and 44% in P. panamensis. The species of bacteria that share these corals are B. subtilis and Staphylococcus hominis. It is suggested that the identified adherent species have the ability to colonize coral mucus, are commensal and potentially beneficial, because they were isolated from apparently healthy corals.

2016 ◽  
Vol 63 (2) ◽  
Author(s):  
Katarzyna Grajek ◽  
Anna Sip ◽  
Joanna Foksowicz-Flaczyk ◽  
Anna Dobrowolska ◽  
Agnieszka Wita

The aim of this study was to determine the degree of adhesion and hydrophobicity of some strains of lactic acid bacteria (LAB) with proven antagonistic properties against pathogenic bacteria. Studies were performed using-LAB strains isolated from the gastrointestinal tract of calves and piglets. These strains exhibited an antibacterial activity against pathogenic strains of Clostridium perfringens and Escherichia coli. Cell adhesiveness was examined in relation to the porcine and bovine mucin. Our analyses had shown that the tested microorganisms demonstrated a degree of adhesion in the range of 32.00-40.00% for strains isolated from calves, and 34.00-40.00% for strains isolated from pigs. The hydrophobicity of tested bacteria was in the range of 31.00%-44.00% for strains isolated from pigs, and 26.00%-42.00% for strains obtained from calves. The best mucin adhesion ability was found for bacterial strains belonging to the Enterococcus genus isolated from calves. Taking into account porcine isolates, the best adhesion was observed for the Leuconostoc bacterial strains. Among tested strains, the highest hydrophobicity, measured in relation to hexadecane, was recorded for the bacterial strains belonging to the Leuconostoc sp. isolated from piglets and a of Lactobacillus sp. bacterial strain isolated from calves.


Processes ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 963
Author(s):  
Jon Kepa Izaguirre ◽  
Leire Barañano ◽  
Sonia Castañón ◽  
Itziar Alkorta ◽  
Luis M. Quirós ◽  
...  

Soybeans and soy-based products contain isoflavones which can be used for nutraceutical and medical applications. In soybeans and in unfermented soy foods, isoflavones are normally present as glycosides. Isoflavone glycosides can be enzymatically converted to isoflavone aglycones, thus releasing the sugar molecule. The effective absorption of isoflavones in humans requires the bioconversion of isoflavone glycosides to isoflavone aglycones through the activity of the enzyme β-glucosidase. The objective was to assess the capacity of 42 bacterial strains (belonging to Lactobacillus, Streptococcus and Enterococcus) to produce β-glucosidase activity. The strain that showed the highest β-glucosidase activity (Lactobacillus plantarum 128/2) was then used for the optimization of the bioconversion of genistin and daidzin present in commercial soymilk to their aglycone forms genistein and daidzein. The contribution of process parameters (temperature, inoculum size, time) to the efficiency of such bioactivation was tested. Lactobacillus plantarum 128/2 was able to completely bioactivate soymilk isoflavones under the following conditions: 25 °C temperature, 2% inoculum size and 48 h process time. These results confirm the suitability of lactic acid bacteria for the bioactivation of isoflavones present in soymilk and provide an interesting candidate (L. plantarum 182/2) for food industries to perform this transformation.


2021 ◽  
Vol 9 (5) ◽  
pp. 974
Author(s):  
Marc-Kevin Zinn ◽  
Marco Singer ◽  
Dirk Bockmühl

Although malodour formation on textiles and in washing machines has been reported to be a very relevant problem in domestic laundry, the processes leading to bad odours have not been studied intensively. In particular, the smell often described as “wet-and-dirty-dustcloth-like malodour” had not been reproduced previously. We developed a lab model based on a bacterial mixture of Micrococcus luteus, Staphylococcus hominis, and Corynebacterium jeikeium, which can produce this odour type and which might allow the detailed investigation of this problem and the development of counteractions. The model uses bacterial strains that have been isolated from malodourous textiles. We could also show that the three volatile compounds dimethyl disulfide, dimethyl trisulfide, and indole contribute considerably to the “wet-fabric-like” malodour. These substances were not only found to be formed in the malodour model but have already been identified in the literature as relevant malodourous substances.


2018 ◽  
Vol 6 (2) ◽  
pp. 500-508
Author(s):  
Julie Ann A. Arcales ◽  
Garner Algo L.Alolod

Isolation and characterization of bacteria in food products are important to determine and distinguish the beneficial or harmful effects of microbiota in certain samples. Lactic acid bacteria in food products had long been associated to good factors as food preservatives and with added fermentation metabolites. This study isolated and characterized lactic acid bacteria from burong bangus. The culture and purification process of bacteria isolation resulted to 4 strains of lactic acid bacteria namely Enterococcus faecalis, Tetragenococcus muriaticus, Lactobacillus delbrueckii subp. delbrueckii and Carnobacterium divergens. High enzymatic activity were observed with E. faecalis particularly on lipase and protease assay. While C. divergens have no enzymatic activity against lipase, protease, amylase and cellulase. The antimicrobial property of L. delbrueckii is only susceptible to amoxicillin unlike the other three bacteria isolates. No antagonistic activity were observed with the four bacterial strains against Bacillus subtilis, Staphylococcus aureus and Escherichia coli. The result of this study showed promising benefits to the industry especially in developing countries like the Philippines because population are not yet so aware of this organisms and the benefits that can be derived through their consumption.


Author(s):  
Petr Doležal ◽  
Dušan Kořínek ◽  
Jan Doležal ◽  
Václav Pyrochta

In the experiment was the effect of biological additive on the fermentation quality of crushed maize ears of two hybrids by comparing with the untreated control. The bacterial inoculant „A“ contained selected bacterial strains of Lactobacillus rhamnosus (NCIMB 30121) and Enterococcus faecium (NCIMB 30122). As effective substances of bacterial water–soluble inoculant „B“ were selected bacterial strains of Lactobacillus rhamnosus (NCIMB 30121), Lactobacillus plantarum (DSM 12836), Lactobacillus brevis (DSM 12835), Lactobacillus buchneri (DSM 12856), Pediococcus acidialactici (P. pentosaceus) (DSM 12834). The addition of inoculant „A“ in our experiment conditions increased statistically significantly (P<0.01) the pH value (4.09±0.01), resp. 4.02±0.02 in second trial with Pedro hybrid. The bacterial inoculant „B“ increased significantly (P<0.01) the contents of lactic acid (50.95±0.1.87 g/kg DM), acetic acid (18.61±0.34 g/kg DM), sum of acids (69.55±1.62 g/kg DM) and decreased (P<0.01) in the first trial the ethanol content (5.41±0.45 g/kg DM). The highest DM content (P<0.01) was in all experimental inoculated silages with additive „A“ (54.26±0.86%, and 53.56±0.54%, resp.). The bacterial inoculant „A“ increased significantly (P<0.01) in comparison with control silage in the second trial the content of lactic acid (34.66Ī2.81 g/kg DM), sum of acids (44.68±3.54 g/kg DM), the total acids content (32.87±2.88 g/kg DM), and ethanol content (17.33±0.79 g/kg DM). The inoculation positive effect was demonstrated in reduction of ethanol amount and of total acid production. The pH value of inoculated silages was not significantly lower than that in the control silage.


Author(s):  
Roseline Eleojo Kwasi ◽  
Iyanuoluwa Gladys Aremu ◽  
Qudus Olamide Dosunmu ◽  
Funmilola A. Ayeni

Background: Ogi constitutes a rich source of lactic acid bacteria (LAB) with associated health benefits to humans through antimicrobial activities. However, the high viability of LAB in Ogi and its supernatant (Omidun) is essential. Aims: This study was carried out to assess the viability of LAB in various forms of modified and natural Ogi and the antimicrobial properties of Omidun against diarrhoeagenic E coli. Methods and Material: The viability of LAB was assessed in fermented Ogi slurry and Omidun for one month and also freeze-dried Ogi with and without added bacterial strains for two months. A further 10 days viability study of modified Omidun, refrigerated Omidun, and normal Ogi was performed. The antimicrobial effects of modified Omidun against five selected strains of diarrhoeagenic E. coli (DEC) were evaluated by the co-culture method. Results: Both drying methods significantly affected carotenoids and phenolic compounds. The Ogi slurry had viable LAB only for 10 days after which, there was a succession of fungi and yeast. Omidun showed 2 log10cfu/ml reduction of LAB count each week and the freeze-dried Ogi showed progressive reduction in viability. Refrigerated Omidun has little viable LAB, while higher viability was seen in modified Omidun (≥2 log cfu/ml) than normal Omidun. Modified Omidun intervention led to 2-4 log reduction in diarrhoeagenic E. coli strains and total inactivation of shigella-toxin producing E. coli H66D strain in co-culture. Conclusions: The consumption of Ogi should be within 10 days of milling using modified Omidun. There are practical potentials of consumption of Omidun in destroying E. coli strains implicated in diarrhea. Keywords: Ogi, Omidun, lactic acid bacteria, diarrhoeagenic Escherichia coli strains, Viability.


2016 ◽  
Vol 10 (1) ◽  
pp. 37-41
Author(s):  
Fatima Abood Chaloob

Infection with hepatitis C virus (HCV) imposes a global challenge with over 180 million cases worldwide. Only few patients spontaneously had their virus neutralized, while most patients develop chronic HCV infection. This implies a key role of genetic factors in viral clearance or persistence. The current study aimed at clarifying the effect of certain single nucleotide polymorphisms (SNPs) on individual's susceptibility to HCV infection.  A total of 60 patients with confirmed HCV infection and 35 apparently healthy individuals were enrolled in this study. Blood sample was obtained from each participant, from which DNA was extracted. The JAK1gene was amplified with conventional PCR technique using three sets of primers targeting three SNPs in this gene: rs2780895, rs4244165 and rs17127024. Restriction fragment length polymorphism (RFLP) was used for genotyping of PCR products. Each of rs2780895 and rs17127024 had two genotypes in both patients and controls, however, only the heterozygous genotype of the SNP rs2780895 (CT) significantly associated with the susceptibility to HCV. The SNP rs4244165 appeared in only with homozygous wild genotype (GG) in both patients and controls. It can be concluded that allele T of the SNP rs2780895 could be considered as a risk factor for infection with HCV


2011 ◽  
Vol 74 (4) ◽  
pp. 631-635 ◽  
Author(s):  
VASILIKI A. BLANA ◽  
AGAPI I. DOULGERAKI ◽  
GEORGE-JOHN E. NYCHAS

Fifteen fingerprints (assigned to Leuconostoc spp., Leuconostoc mesenteroides, Weissella viridescens, Leuconostoc citreum, and Lactobacillus sakei) of 89 lactic acid bacteria (LAB) isolated from minced beef stored under modified atmospheres at various temperatures were screened for their ability to exhibit autoinducer-2 (AI-2)–like activity under certain growth conditions. Cell-free meat extracts (CFME) were collected at the same time as the LAB isolates and tested for the presence of AI-2–like molecules. All bioassays were conducted using the Vibrio harveyi BAA-1117 (sensor 1−, sensor 2+) biosensor strain. The possible inhibitory effect of meat extracts on the activity of the biosensor strain was also evaluated. AI-2–like activity was observed for Leuconostoc spp. isolates, but none of the L. sakei strains produced detectable AI-2–like activity. The AI-2–like activity was evident mainly associated with the Leuconostoc sp. B 233 strain, which was the dominant isolate recovered from storage at 10 and 15°C and at the initial and middle stages of storage at chill temperatures (0 and 5°C). The tested CFME samples displayed low AI-2–like activity and inhibited AI-2 activity regardless of the indigenous bacterial populations. The LAB isolated during meat spoilage exhibited AI-2–like activity, whereas the LAB strains retrieved depended on storage time and temperature. The production of AI-2–like molecules may affect the dominance of different bacterial strains during storage. The results provide a basis for further research concerning the effect of storage temperature on the expression of genes encoding AI-2 activity and on the diversity of the ephemeral bacterial population.


Sign in / Sign up

Export Citation Format

Share Document