Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 39
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Foods ; 12(12)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37372532

RESUMO

Microorganisms have long been essential to human life, playing significant roles in food and beverage production, health and disease, and the environment [...].

2.
Antioxidants (Basel) ; 12(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36670977

RESUMO

Bee pollen represents one of the most complete natural foods playing an important role in the diet for its health qualities and therapeutic properties. This work aimed to characterize a Tuscan bee pollen by evaluating its phytochemical profile and the in vitro and ex vivo antioxidant activities. The isolation and taxonomic and functional characterization of yeasts in the sample has been also conducted. Finally, the pollen anti-inflammatory potential has been assessed on a TNFα-inflamed human colorectal adenocarcinoma cell line (HT-29). Our results highlighted a good phytochemical composition in terms of polyphenols, flavonoids, flavonols, monomeric anthocyanins, and carotenoids. In addition, we detected good antioxidant activity and radical scavenging capacity by in vitro and ex vivo assays, as well as good antioxidant activity by isolated yeasts. Data showed no cytotoxic effects of bee pollen extracts, with average viability values >80% at each tested dose. Moreover, TNFα treatment did not affect HT-29 viability while upregulating IL-8, COX-2, and ICAM-1 gene expression, otherwise reduced by both doses of bee pollen. In conclusion, our sample represents an interesting functional food and a potential probiotic product, having high phytochemical compound levels and good antioxidant activities, as well as anti-inflammatory effects on the TNFα-inflamed HT-29 cell line.

3.
Int J Mol Sci ; 24(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36674853

RESUMO

The differential effects of UV-B on the inhibition or activation of protective mechanisms to maintain cells photosynthetically active were investigated in native microalgae. Four strains were used, including two Chlorella sorokiniana strains, F4 and LG1, isolated from a Mediterranean inland swamp and a recycled cigarette butt's substrate, respectively, and two isolates from an Ecuadorian highland lake related to Pectinodesmus pectinatus (PEC) and Ettlia pseudoalveolaris (ETI). Monocultures were exposed to acute UV-B (1.7 W m-2) over 18 h under controlled conditions. UV-B-untreated microalgae were used as the control. Comparative physiological responses, including photosynthetic pigments, non-enzymatic antioxidants, and chlorophyll a fluorescence, were evaluated at specific time points. Results showed that UV-B significantly compromised all the physiological parameters in F4, thereby resulting in the most UV-B-sensitive strain. Contrarily, UV-B exposure did not lead to changes in the PEC physiological traits, resulting in the best UV-B-resistant strain. This could be attributed to the acclimation to high light habitat, where maintaining a constitutive phenotype (at the photosynthetic level) is strategically advantageous. Differently, LG1 and ETI at 12 h of UV-B exposure showed different UV-B responses, which is probably related to acclimation, where in LG1, the pigments were recovered, and the antioxidants were still functioning, while in ETI, the accumulation of pigments and antioxidants was increased to avoid further photodamage. Consequently, the prolonged exposure in LG1 and ETI resulted in species-specific metabolic regulation (e.g., non-enzymatic antioxidants) in order to constrain full photoinhibition under acute UV-B.


Assuntos
Chlorella , Microalgas , Clorofila/metabolismo , Clorofila A , Microalgas/metabolismo , Chlorella/metabolismo , Equador , Fotossíntese , Antioxidantes/metabolismo , Raios Ultravioleta
4.
Front Biosci (Landmark Ed) ; 27(11): 305, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36472111

RESUMO

BACKGROUND: Azurin, a bacterial cupredoxin firstly isolated from the bacterium Pseudomonas aeruginosa, is considered a potential alternative therapeutic tool against different types of cancer. AIMS: In this work we have explored the relationship possibly existing between azurin and colorectal cancer (CRC), in light of the evidence that microbial imbalance can lead to CRC progression. METHODOLOGY/RESULTS: To this aim, the presence of azurin coding gene in the DNA extracted from saliva, stool, and biopsy samples of 10 CRC patients and 10 healthy controls was evaluated by real-time PCR using primers specifically designed to target the azurin coding gene from different bacterial groups. The correlation of the previously obtained microbiota data with real-time PCR results evidenced a "preferential" enrichment of seven bacterial groups in some samples than in others, even though no statistical significance was detected between controls and CRC. The subset of azurin gene-harbouring bacterial groups was representative of the entire community. CONCLUSIONS: Despite the lack of statistical significance between healthy and diseased patients, HTS data analysis highlighted a kind of "preferential" enrichment of seven bacterial groups harbouring the azurin gene in some samples than in others.


Assuntos
Azurina , Microbiota , Humanos , Azurina/genética , Genes Bacterianos , Pseudomonas aeruginosa/genética , Microbiota/genética
5.
Microorganisms ; 10(9)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36144344

RESUMO

Endophytes are beneficial microorganisms exerting growth-promoting activities in plants; they are most often located within the plant intercellular spaces and can be found in all plant tissues, including roots, leaves, stems, flowers, and seeds. In this work, we investigated the cultivable bacterial community of the seeds and the two-week sprouts of the Cannabis sativa L. cultivar "Futura 75". Endophytes were genotypically and phenotypically characterized and were exposed to different concentrations of seed extracts to verify their susceptibility. A bacterial strain among all the isolates was selected for germination tests of C. sativa in different experimental conditions. The results revealed the dominance of Firmicutes (Staphylococcus sp.) among the isolated strains. Two strains were different from the others for indole-3-acetic acid (IAA) production and for their resistance patterns towards abiotic and biotic stresses. The Sphingomonas sp. strain Can_S11 (Alphaproteobacteria) showed a potential ability to increase the nutraceutical features of its sprouts, particularly an increase in the polyphenol content and antioxidant activity. None of the isolated strains were susceptible to the seed extracts, which were previously tested as antimicrobial and antibiofilm agents against human pathogenic bacteria. The results open new perspectives for the study of the endophytes of C. sativa as possible biostimulants.

6.
Plants (Basel) ; 11(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36145757

RESUMO

In this study, the potential of ultraviolet B (UV-B) radiation to alleviate the effects of pollutants in cigarette butt wastewater (CBW) was investigated using different Chlorella sorokiniana strains (F4, R1 and LG1). Microalgae were treated with UV-B (1.7 W m-2) for 3 days prior to their exposure to CBW and then incubated for 4 days in the absence or presence of UV-B. UV-B-untreated microalgae were used as the control. Comparative physiological responses, including photosynthetic pigments and non-enzymatic antioxidants, as well as nicotine and nicotyrine removal, were evaluated in 7-day cultures. UV-B treatments did not negatively impact algal chlorophyll or carotenoid production. UV-B acclimation was strain-dependent, correlating with native environment adaptations and genetic constitutions. UV-B as a pretreatment had long-term positive effects on non-enzymatic antioxidant capacity. However, LG1 needed more time to readjust the pro-oxidant/antioxidant balance, as it was the most UV-B-sensitive. Phenolic compounds played an important role in the antioxidant system response to UV-B, while flavonoids did not contribute to the total antioxidant capacity. Although cross-resistance between UV-B and CBW was observed in F4 and R1, only R1 showed nicotine/nicotyrine catabolism induction due to UV-B. Overall, the results suggest that UV-B activates defense pathways associated with resistance or tolerance to nicotine and nicotyrine.

7.
Plants (Basel) ; 11(13)2022 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-35807722

RESUMO

Microalgal-based remediation is an ecofriendly and cost-effective system for wastewater treatment. This study evaluated the capacity of microalgae in the remediation of wastewater from cleaning process of smoked cigarette butts (CB). At laboratory scale, six strains (one from the family Scenedesmaceae, two Chlamydomonas debaryana and three Chlorella sorokiniana) were exposed to different CB wastewater dilutions to identify toxicity levels reflected in the alteration of microalgal physiological status and to determine the optimal conditions for an effective removal of contaminants. CB wastewater could impact on microalgal chlorophyll and carotenoid production in a concentration-dependent manner. Moreover, the resistance and remediation capacity did not only depend on the microalgal strain, but also on the chemical characteristics of the organic pollutants. In detail, nicotine was the most resistant pollutant to removal by the microalgae tested and its low removal correlated with the inhibition of photosynthetic pigments affecting microalgal growth. Concerning the optimal conditions for an effective bioremediation, this study demonstrated that the Chlamydomonas strain named F2 showed the best removal capacity to organic pollutants at 5% CB wastewater (corresponding to 25 butts L−1 or 5 g CB L−1) maintaining its growth and photosynthetic pigments at control levels.

8.
Foods ; 11(10)2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35626969

RESUMO

The Mediterranean diet has, among its cornerstones, the use of olive oil for its nutraceutical and organoleptic properties. Despite the numerous merits, olive-oil mill wastewater (OMWW), which is generated by the olive-oil extraction process, is one of the most serious environmental pollutants in the Mediterranean countries. The polluting potential of OMWW is due to its high content of tannins, polyphenols, polyalcohols, pectins and lipids. In order to close the recovery cycle of a fortified citrus olive oils previously developed, we tested the ability of five microalgae of the Chlorella group (SEC_LI_ChL_1, CL_Sc, CL_Ch, FB and Idr) in lowering the percentage of total phenolic compounds in vegetation water. This was obtained with three different extraction processes (conventional, and lemon and orange peels) at three concentrations each (10%, 25% and 50%). The results showed that strains Idr, FB and CL_Sc from the Lake Massaciuccoli can tolerate vegetation water from conventional and lemon peel extractions up to 25%; these strains can also reduce the phenolic compounds within the tests. The application of microalgae for OMWW treatment represents an interesting opportunity as well as an eco-friendly low-cost solution to be developed within companies as a full-scale approach, which could be applied to obtain a fortified microalgal biomass to be employed in nutraceutical fields.

9.
Foods ; 11(5)2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35267283

RESUMO

The increasing global population and the simultaneous growing attention to natural, sustainable, and healthier products are driving the food industry towards research on alternative food sources. In this scenario, microalgae are gaining worldwide attention as "functional feedstocks" for foods, feeds, supplements, and nutraceutical formulations, being a source of high-value metabolites including polyphenols and other antioxidant compounds. In this work, eleven microalgal strains from freshwater environments were evaluated for their nutraceutical properties, focusing on photosynthetic pigments, total polyphenols, and flavonoid content, as well as in vitro antioxidant activities. Data helped to select those strains showing the most promising features for simultaneous massive growth and bioactive compound production. Results highlighted that the microalgae have variable values for both biochemical parameters and antioxidant activities, mainly depending on the solvents and applied treatment rather than on the isolation sources or the phylogenetic attribution. According to our results, the putative best candidates for massive cultivation under laboratory conditions for the simultaneous extraction of different molecules with nutraceutical potential are strains F1 (Scenedesmaceae), F3 (Chlamydomonas debariana), R1 (Chlorella sorokiniana), and C2 (Chlorella-like).

10.
Front Plant Sci ; 13: 1076573, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36743570

RESUMO

Introduction: Bituminaria bituminosa is a medicinal plant recognized for its phytochemicals, such as furanocoumarins, pterocarpans, and flavonoids. Since the secondary metabolism is influenced by the plant-endophyte interactions, the endophytic bacterial community of B. bituminosa was explored and the possible interactions with the plant were described. Materials and methods: Different bacterial strains were isolated from different organs of in vitro plants as shoots, roots, and seeds. The bacterial strains were identified and phenotypically characterized for different traits; strains were also exposed to different concentrations of B. bituminosa plant extract showing different susceptibility, probably determined by different secondary metabolites produced by the plant in the different organs (i.e. aerial parts and roots). Results and discussion: Bacterial strains showed different phenotypic characteristics; the 6 detected haplotypes were dominated by a single species related to Stenotrophomonas rhizophila. Endophytes isolated from the aerial parts produced a higher indole-3-acetic acid (IAA) amount than those of the roots, while all strains were unable to produce biosurfactants and antagonistic activity toward the other strains. The research opens new perspectives for future analysis addressed to test the susceptibility of the endophytic bacterial community of B. bituminosa toward the pure compounds extracted from the plants, and to investigate the role of these compounds on the distribution of endophytes within the different plant tissues.

11.
Microbiome ; 9(1): 152, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193273

RESUMO

BACKGROUND: The human microbiota plays several roles in health and disease but is often difficult to determine which part is in intimate relationships with the host vs. the occasional presence. During the Mars500 mission, six crewmembers lived completely isolated from the outer world for 520 days following standardized diet regimes. The mission constitutes the first spaceflight simulation to Mars and was a unique experiment to determine, in a longitudinal study design, the composition and importance of the resident vs. a more variable microbiota-the fraction of the human microbiota that changes in time and according to environmental conditions-in humans. METHODS: Here, we report the characterization of the salivary microbiota from 88 samples taken during and after Mars500 mission for a total of 720 days. Amplicon sequencing of the V3-V4 regions of 16S rRNA gene was performed, and results were analyzed monitoring the diversity of the microbiota while evaluating the effect of the three main variables present in the experimental system: time, diet, and individuality of each subject. RESULTS: Results showed statistically significant effects for either time, diet, and individuality of each subject. The main contribution came from the individuality of each subject, emphasizing salivary microbiota-personalized features, and an individual-based resilience of the microbiota. CONCLUSIONS: The uniqueness of Mars500 mission, allowed to dampen the effect of environmental variables on salivary microbiota, highlighting its pronounced personalization even after sharing the same physical space for more than a year. Video abstract.


Assuntos
Microbiota , Voo Espacial , Dieta , Humanos , Estudos Longitudinais , RNA Ribossômico 16S/genética
12.
Microorganisms ; 10(1)2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-35056457

RESUMO

Azurin is a bacterial-derived cupredoxin, which is mainly involved in electron transport reactions. Interest in azurin protein has risen in recent years due to its anticancer activity and its possible applications in anticancer therapies. Nevertheless, the attention of the scientific community only focused on the azurin protein found in Pseudomonas aeruginosa (Proteobacteria, Gammaproteobacteria). In this work, we performed the first comprehensive screening of all the bacterial genomes available in online repositories to assess azurin distribution in the three domains of life. The Azurin coding gene was not detected in the domains Archaea and Eucarya, whereas it was detected in phyla other than Proteobacteria, such as Bacteroidetes, Verrucomicrobia and Chloroflexi, and a phylogenetic analysis of the retrieved sequences was performed. Observed patchy distribution and phylogenetic data suggest that once it appeared in the bacterial domain, the azurin coding gene was lost in several bacterial phyla and/or anciently horizontally transferred between different phyla, even though a vertical inheritance appeared to be the major force driving the transmission of this gene. Interestingly, a shared conserved domain has been found among azurin members of all the investigated phyla. This domain is already known in P. aeruginosa as p28 domain and its importance for azurin anticancer activity has been widely explored. These findings may open a new and intriguing perspective in deciphering the azurin anticancer mechanisms and to develop new tools for treating cancer diseases.

13.
Environ Sci Pollut Res Int ; 28(7): 8539-8555, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33064280

RESUMO

Treating biosolids from industrial, urban, and agricultural plants produces high amounts of water. After organic pollutants and non-essential heavy metals have been removed, these wastewaters are still rich in trace elements such as zinc (Zn), copper, or manganese (Mn) and have high conductivity and extremely variable pH. In this study, an isolated Chlorella sp. strain was grown for 21 days in nutrient solutions enriched with known amounts of Zn or Mn to obtain concentrations three (4.0 mg L-1)- and six (1.0 mg L-1)-fold higher than the basal medium levels, respectively, and over the limits permitted in aquatic environments. The green alga exhibited high tolerance to Zn and Mn, with the maximum abatement of Zn (28-30%) and Mn (60-63.5%) after 14 and 7 days of culture, respectively. Mn stimulated the growth rate and biomass production of Chlorella, which showed the highest carbon levels just in the first week. In both treatments, the nitrogen and protein contents remarkably increased. The photosynthetic pigments increased until the 14th day, with a higher extent in the Zn-enriched solution. An increasing photochemical efficiency was observed after 7 days of treatment, when the microalgae grown in Zn- and Mn-enriched solutions showed a slightly higher maximum photochemical efficiency than control. The autotrophic and controlled growth system adopted was designed to monitor the dynamic balance of Zn and Mn contents in the solutions and in the algal biomass. This system has proved to be useful in identifying the optimal nutritional conditions of the microalgae, along with the optimal temporal patterns of both metal biosorption capacity for water remediation and element bioaccumulation in the algal biomass.


Assuntos
Chlorella , Metais Pesados , Cobre , Manganês , Zinco
14.
Front Plant Sci ; 11: 607651, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33362836

RESUMO

Aquatic ecosystems represent one of the largest reservoirs of phytoplankton accounting for most of the primary production of the Earth. The Lake Massaciuccoli located in Tuscany (Italy) is one of the largest swamps that in ancient times entirely covered the Versilia coastal plain. Despite its peculiar features, especially the eutrophic characteristics, its native microalgal consortia have never been explored up to now. In this work, we isolated and described four autochthonous microalgal strains from different sites in the lake (FB, Idr, CL_Sc, and CL_Ch); the four microalgal strains were identified within the Chlorella sorokiniana clade. We exposed them to ten of the most common or emerging environmental contaminants in order to describe their preliminary response to the tested substances: five metals (As, Fe, Ni, Cu, and Zn), two herbicides (Metolachlor and Sethoxydim), two antibiotics (Ciprofloxacin and Benzylpenicillin) and a non-steroidal anti-inflammatory drug (Ibuprofen). Physiological response of the strains highlighted intraspecific differences; strain CL_Sc was the most tolerant in presence of metals while strain Idr was the most sensitive. All strains were sensitive to sethoxydim and tolerant to metolachlor at all the tested concentrations. Strains FB and Idr were the most sensitive in presence of Ibuprofen while strain CL_Ch was the most sensitive to the highest Benzylpenicillin concentration. Resistance pattern of strain Idr somehow reflects both the phylogenetic and the geographic "isolation" from all other three strains. Finally, optical microscope observation confirmed some differences also in the microalgae morphological aspect. Overall, all the strains showed interesting responses in presence of high concentrations of the tested substances, representing putative interesting candidates for water remediation in wastewater treatment plants.

15.
Front Immunol ; 11: 573158, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33488574

RESUMO

Background and aim: Gut microbiota (GM) can support colorectal cancer (CRC) progression by modulating immune responses through the production of both immunostimulatory and/or immunosuppressive cytokines. The role of IL-9 is paradigmatic because it can either promote tumor progression in hematological malignancies or inhibit tumorigenesis in solid cancers. Therefore, we investigate the microbiota-immunity axis in healthy and tumor mucosa, focusing on the correlation between cytokine profile and GM signature. Methods: In this observational study, we collected tumor (CRC) and healthy (CRC-S) mucosa samples from 45 CRC patients, who were undergoing surgery in 2018 at the Careggi University Hospital (Florence, Italy). First, we characterized the tissue infiltrating lymphocyte subset profile and the GM composition. Subsequently, we evaluated the CRC and CRC-S molecular inflammatory response and correlated this profile with GM composition, using Dirichlet multinomial regression. Results: CRC samples displayed higher percentages of Th17, Th2, and Tregs. Moreover, CRC tissues showed significantly higher levels of MIP-1α, IL-1α, IL-1ß, IL-2, IP-10, IL-6, IL-8, IL-17A, IFN-γ, TNF-α, MCP-1, P-selectin, and IL-9. Compared to CRC-S, CRC samples also showed significantly higher levels of the following genera: Fusobacteria, Proteobacteria, Fusobacterium, Ruminococcus2, and Ruminococcus. Finally, the abundance of Prevotella spp. in CRC samples negatively correlated with IL-17A and positively with IL-9. On the contrary, Bacteroides spp. presence negatively correlated with IL-9. Conclusions: Our data consolidate antitumor immunity impairment and the presence of a distinct microbiota profile in the tumor microenvironment compared with the healthy mucosa counterpart. Relating the CRC cytokine profile with GM composition, we confirm the presence of bidirectional crosstalk between the immune response and the host's commensal microorganisms. Indeed, we document, for the first time, that Prevotella spp. and Bacteroides spp. are, respectively, positively and negatively correlated with IL-9, whose role in CRC development is still under debate.


Assuntos
Adenocarcinoma/imunologia , Adenocarcinoma/microbiologia , Bacteroides/isolamento & purificação , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/microbiologia , Microbioma Gastrointestinal , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Prevotella/isolamento & purificação , Adenocarcinoma/metabolismo , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Interleucina-9/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/cirurgia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Masculino , Pessoa de Meia-Idade , Ribotipagem , Linfócitos T/imunologia , Linfócitos T/metabolismo , Microambiente Tumoral
16.
Front Microbiol ; 10: 510, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31001206

RESUMO

Rheinheimera sp. strain EpRS3, isolated from the rhizosphere of Echinacea purpurea, is already known for its ability to produce antibacterial compounds. By use of culture experiments, we verified and demonstrated its harmful effect against the ciliated protist Euplotes aediculatus (strain EASCc1), which by FISH experiments resulted to harbor in its cytoplasm the obligate bacterial endosymbiont Polynucleobacter necessarius (Betaproteobacteria) and the secondary endosymbiont "Candidatus Nebulobacter yamunensis" (Gammaproteobacteria). In culture experiments, the number of ciliates treated both with liquid broth bacteria-free (Supernatant treatment) and bacteria plus medium (Tq treatment), decreases with respect to control cells, with complete disappearance of ciliates within 6 h after Tq treatment. Results suggest that Rheinheimera sp. EpRS3 produces and releases in liquid culture one or more bioactive molecules affecting E. aediculatus survival. TEM analysis of control (not treated) ciliates allowed to morphologically characterize both kind of E. aediculatus endosymbionts. In treated ciliates, collected soon after the arising of cell suffering leading to death, TEM observations revealed some ultrastructural damages, indicating that P. necessarius endosymbionts went into degradation and vacuolization after both Supernatant and Tq treatments. Additionally, TEM investigation showed that when the ciliate culture was inoculated with Tq treatment, both a notable decrease of P. necessarius number and an increase of damaged and degraded mitochondria occur. FISH experiments performed on treated ciliates confirmed TEM results and, by means of the specific probe herein designed, disclosed the presence of Rheinheimera sp. EpRS3 both inside phagosomes and free in cytoplasm in ciliates after Tq treatment. This finding suggests a putative ability of Rheinheimera sp. EpRS3 to reintroduce itself in the environment avoiding ciliate digestion.

17.
FEMS Microbiol Ecol ; 94(12)2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30202963

RESUMO

Epilithic river biofilms characterize the rock surfaces along the Acquarossa river (Viterbo, Italy); they are in part red and in part black colored, maintaining a well-defined borderline. This peculiarity has raised questions about the biotic and abiotic phenomena that might avoid the mixing of the two biofilms. In this study, the structuring of bacterial communities in black and red epilithic biofilm in the Acquarossa river has been investigated with both culture dependent and independent approaches. Data obtained highlighted a (very) different taxonomic composition of black and red epilithons bacterial communities, dominated by Acinetobacter sp. and iron-oxidizing bacteria, respectively. The chemical characterization of both river water and biofilms revealed a substantial heavy metals pollution of the environment; heavy metals were also differentially accumulated in red and black epilithons. Overall, our data revealed that the structuring of red and black epilithons might be affected mainly by the antagonistic interactions exhibited by bacterial genera dominating the two biofilms. These findings suggest that biotic factors might be responsible for the structuring of natural bacterial communities, suggesting that there is a selection of populations at very small scale, and that different populations might compete for different niches.


Assuntos
Acinetobacter/metabolismo , Biofilmes/crescimento & desenvolvimento , Metais Pesados/análise , Pseudomonas/metabolismo , Rodófitas/microbiologia , Poluentes Químicos da Água/análise , Acinetobacter/classificação , Biofilmes/classificação , Ferro/química , Itália , Oxirredução , Pseudomonas/classificação , Rios/microbiologia , Microbiologia do Solo
18.
FEMS Microbiol Ecol ; 94(8)2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29912319

RESUMO

A key factor in the study of plant-microbes interactions is the composition of plant microbiota, but little is known about the factors determining its functional and taxonomic organization. Here we investigated the possible forces driving the assemblage of bacterial endophytic and rhizospheric communities, isolated from two congeneric medicinal plants, Echinacea purpurea (L.) Moench and Echinacea angustifolia (DC) Heller, grown in the same soil, by analysing bacterial strains (isolated from three different compartments, i.e. rhizospheric soil, roots and stem/leaves) for phenotypic features such as antibiotic resistance, extracellular enzymatic activity, siderophore and indole 3-acetic acid production, as well as cross-antagonistic activities. Data obtained highlighted that bacteria from different plant compartments were characterized by specific antibiotic resistance phenotypes and antibiotic production, suggesting that the bacterial communities themselves could be responsible for structuring their own communities by the production of antimicrobial molecules selecting bacterial-adaptive phenotypes for plant tissue colonization.


Assuntos
Antibacterianos/metabolismo , Antibiose/fisiologia , Bactérias/crescimento & desenvolvimento , Echinacea/microbiologia , Folhas de Planta/microbiologia , Raízes de Plantas/microbiologia , Caules de Planta/microbiologia , Rizosfera , Bactérias/efeitos dos fármacos , Bactérias/genética , Resistência Microbiana a Medicamentos , Ácidos Indolacéticos/metabolismo , Microbiota/efeitos dos fármacos , Solo , Microbiologia do Solo , Especificidade da Espécie
19.
Genome Announc ; 5(25)2017 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-28642378

RESUMO

We announce here the draft genome sequence of Arthrobacter sp. strain EpSL27, isolated from the stem and leaves of the medicinal plant Echinacea purpurea and able to inhibit human-pathogenic bacterial strains. The genome sequencing of this strain may lead to the identification of genes involved in the production of antimicrobial molecules.

20.
Genome Announc ; 5(20)2017 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-28522712

RESUMO

In this announcement, we detail the draft genome sequence of the Pseudomonas sp. strain Ep R1, isolated from the roots of the medicinal plant Echinacea purpurea The elucidation of this genome sequence may allow the identification of genes associated with the production of antimicrobial compounds.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...