391 registros encontrados - unidade Centro Pluridisciplinar de Pesquisas Químicas, Biológicas e Agrícolas
ARTIGO - Inglês
Assunto: Atividade antitumoral
Natural products containing the α,β‐unsaturated δ‐lactone skeleton have been shown to possess a variety of biological activities. The natural product...
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Natural products containing the α,β‐unsaturated δ‐lactone skeleton have been shown to possess a variety of biological activities. The natural product (−)‐tarchonanthuslactone (1 ) possessing this privileged scaffold is a popular synthetic target, but its
ARTIGO - Inglês
Assunto: Anticâncer
A biologically relevant natural pigment, 1,6-dihydroxy-3-methyl-9,10-anthraquinone 1, widely produced by fungus from Phoma genus, has been isolated...
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A biologically relevant natural pigment, 1,6-dihydroxy-3-methyl-9,10-anthraquinone 1, widely produced by fungus from Phoma genus, has been isolated from Cassia sophera Linn. (Caesalpiniaceae) roots and subjected to detailed spectral studies, including ID-and 2D-NMR. The compound 1 inhibits the proliferation of several cancer cell lines at different extents, showing minor effects on the growth of non-tumorogenic keratinocyte cells
Texto completo: http://nopr.niscair.res.in/handle/123456789/43272
7,7-Dimethylaporphine and other alkaloids from the bark of guatteria friesiana
ARTIGO - Inglês
Assunto: Alcaloides
Phytochemical investigation of the bark of Guatteria friesiana afforded 12 new aporphines (1–12), along with nine known alkaloids (13–21). The...
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Phytochemical investigation of the bark of Guatteria friesiana afforded 12 new aporphines (1–12), along with nine known alkaloids (13–21). The structures of the new alkaloids were determined on the basis of spectroscopic data interpretation. The cytotoxic activity of the isolated compounds against a small panel of tumor cell lines was assessed using the Alamar blue assay
9-Benzoyl 9-deazaguanines as potent xanthine oxidase inhibitors
ARTIGO - Inglês
Assunto: Xantina oxidase
A novel potent xanthine oxidase inhibitor, 3-nitrobenzoyl 9-deazaguanine (LSPN451), was selected from a series of 10 synthetic derivatives. The...
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A novel potent xanthine oxidase inhibitor, 3-nitrobenzoyl 9-deazaguanine (LSPN451), was selected from a series of 10 synthetic derivatives. The enzymatic assays were carried out using an on-flow bidimensional liquid chromatography (2D LC) system, which allowed the screening, the measurement of the kinetic inhibition constant and the characterization of the inhibition mode. This compound showed a non-competitive inhibition mechanism with more affinity for the enzyme-substrate complex than for the free enzyme, and inhibition constant of 55.1 +/- 9.80 nM, about thirty times more potent than allopurinol. Further details of synthesis and enzymatic studies are presented herein
ARTIGO - Inglês
Assunto: Melipona
The geopropolis is a unique type of propolis produced by some stingless bee species. This product is known in folk medicine for its pharmacological...
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The geopropolis is a unique type of propolis produced by some stingless bee species. This product is known in folk medicine for its pharmacological properties, mainly antimicrobial and antioxidant, but there are few scientific studies that prove these properties. The objective of this study was to evaluate the phenolic composition and the antimicrobial, antioxidant and antiproliferative activities of Melipona quadrifasciata geopropolis. The phenolic characterization of the geopropolis ethanolic extract was evaluated by LC-ESI-QTOF-MS. The antimicrobial activity was carried out against Gram-positive (including multiresistant microorganisms), negative and yeast. The synergistic effect was evaluated in association with Sulfamethoxazole + Trimethoprim. DPPH, ABTS, FRAP, ORAC and HPLC on-line were used to evaluate the antioxidant activity. Antiproliferative activity was assessed by the sulforhodamine B assay. Flavonoids and phenolic acids were identified in the extract, which showed promising antimicrobial activity, partially synergistic effect and antioxidant activity
A membrane aerated biofilm reactor for sulfide control from anaerobically treated wastewater
ARTIGO - Inglês
Assunto: Tratamento anaeróbio
A upflow anaerobic sludge blanket reactor was operated combined to a membrane aerated biofilm reactor for sulfate removal and for elemental sulfur...
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A upflow anaerobic sludge blanket reactor was operated combined to a membrane aerated biofilm reactor for sulfate removal and for elemental sulfur reclamation. A commercial silicon tube was used as an oxygen delivery diffuser. The process achieved high rates of sulfide removal from the liquid phase (90%). The hydrogen sulfide removal was influenced by the pH value and at pH value of 7.5, 98% of the H2S was removed. The elemental sulfur was observed inside the membrane, with content in the biomass of 21%. Through the massive sequencing of the samples, the microbial community diversity and the stratification of biomass inside the silicon tube was demonstrated, confirming the presence of sulfide-oxidizing bacteria on the membrane wall. The most important genera found related to the sulfur cycle were Sulfuricurvum, Geovibrio, Flexispira and Sulforospirillum
A modified QuECHERS method for determination of organophosphate esters in milk by GC-MS
ARTIGO - Inglês
Assunto: Artigo original
Abstract: Organophosphate esters (OPEs) are substances that have been detected in several matrices due to their use as flame retardants and...
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Abstract: Organophosphate esters (OPEs) are substances that have been detected in several matrices due to their use as flame retardants and plasticizers. Human exposure to OPEs can cause endocrine disruption, neurotoxicity, and reproductive disturbance. Ingestion of contaminated food can be a significant route of exposure to OPEs. Food can be contaminated by OPEs in the food chain, during cultivation, and by contact with plasticizers during the production chain of processed foods. In this study, a method for the determination of 10 OPEs in commercial bovine milk was developed. The procedure was based on QuEChERS extraction and gas chromatography coupled to mass spectrometry (GC-MS) analysis. QuEChERS modification included a freezing-out step after the extraction followed by the concentration of the entire acetonitrile phase before the clean-up step. Calibration linearity, matrix effects, recovery, and precision were evaluated. Significant matrix effects were observed, which were compensated by matrix-matched calibration curves. Recoveries ranged from 75 to 105%, with a relative standard deviation ranging from 3 to 38%. The method detection limits (MDLs) were in the range of 0.43-4.5 ng mL-1, while the method quantification limits (MQLs) were within the range from 0.98 to 15 ng mL-1. The proposed method was successfully validated and applied to determine the concentrations of OPEs in bovine milk. The 2-ethylhexyl diphenyl phosphate (EHDPHP) was detected in the analyzed milk samples but at levels below the MQL
ARTIGO - Inglês
Assunto: Fungos derivados marinhos
Extracts obtained from 57 marine-derived fungal strains were analyzed by HPLC-PDA, TLC and 1H NMR. The analyses showed that the growth conditions...
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Extracts obtained from 57 marine-derived fungal strains were analyzed by HPLC-PDA, TLC and 1H NMR. The analyses showed that the growth conditions affected the chemical profile of crude extracts. Furthermore, the majority of fungal strains which produced either bioactive of chemically distinctive crude extracts have been isolated from sediments or marine algae. The chemical investigation of the antimycobacterial and cytotoxic crude extract obtained from two strains of the fungus Beauveria felina have yielded cyclodepsipeptides related to destruxins. The present approach constitutes a valuable tool for the selection of fungal strains that produce chemically interesting or biologically active secondary metabolites
A new species of the oligotrophic genus Ochroconis (Sympoventuriaceae)
ARTIGO - Inglês
Assunto: Filogenia
Ochroconis globalis, a novel species of the melanized genus Ochroconis (Sympoventuriaceae, Venturiales), is described and illustrated and...
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Ochroconis globalis, a novel species of the melanized genus Ochroconis (Sympoventuriaceae, Venturiales), is described and illustrated and distinguished phenotypically and molecularly from existing ochroconis-like species. Phylogenetic analyses using nuclear ribosomal DNA genes (nuSSU, ITS, nuLSU) and coding gene fragments (ACT1, BT2, TEF1) revealed clustering of all strains as a monophyletic clade which was well separated from known Ochroconis species. Most strains of the new species were obtained from human-made environments, while the natural habitat of the species remains enigmatic. The new combination Ochroconis musae is introduced for one of the most commonly encountered Ochroconis species, and a phenotypic key to all species is provided
ARTIGO - Inglês
ARTIGO - Inglês
Assunto: Biocatálise
We propose a practical, low-cost and selective fluorescence-based protocol adapted to identify polyethylene terephthalate (PET) degrading...
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We propose a practical, low-cost and selective fluorescence-based protocol adapted to identify polyethylene terephthalate (PET) degrading microorganisms. The microbial hydrolysis of PET nanoparticles was monitored by 2-hydroxyterephthalate, a fluorophore
ARTIGO - Inglês
Assunto: Artigo de pesquisa
Abstract: Although Brazilian livestock is considered one of the most productive in the world, the losses caused by parasites still greatly limit these...
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Abstract: Although Brazilian livestock is considered one of the most productive in the world, the losses caused by parasites still greatly limit these activities and its incorrect control through traditional synthetic chemicals has caused problems such as parasitic resistance. The present study evaluated the anthelmintic and acaricidal action of ethanolic extract (EE) and essential oil (OE) obtained from Achyrocline satureioides inflorescences against an endo and an ectoparasite of great importance in sheep and cattle. The action against Haemonchus contortus was evaluated by the Larval Development Test (LDT) and the Egg Hatching Test (EHT), while the acaricidal potential against Rhipicephalus (Boophilus) microplus was evaluated by the Adult Immersion Test (AIT) and Larval Package Test (LPT). Chemical analyzes were performed by liquid chromatography coupled to mass of spectrometry (LC-MS) and gas chromatography coupled to mass spectrometry (GC-MS) in order to evaluate the chemical composition of EE and EO, respectively. Luteolin (m/z 285), quercetin (m/z 301) and methyl quercetin (m/z 315) were the major compounds detected in the A. satureioides EE, while 41 compounds were identified in EO. Among them, the major compounds were caryophyllene oxide (15.4%), limonene (10.9%), trans-calamenene + d-cadinene (8.0%), (E)-caryophyllene (5.5%), spathulenol (5.1%) and a-pinene (4.5%). Against H. contortus, by EHT, the EE and EO showed LC50 of 83.14 mg mL-1 and 10.42 mg mL-1, respectively. In LDT, LC50 were 0.16 mg mL-1 and 0.42 mg mL-1, respectively by EE and EO. In the AIT assay for R. (B.) microplus tick LC50 obtained for EE and EO were 76.43 mg mL-1 and 114.35 mg mL-1, respectively. EE at 100 mg mL-1 completely inhibited egg laying, while the EO at 50 mg mL-1 completely inhibited larval hatching. No significant larvicidal effect was observed in LPT for both extracts. The EE and EO presented a high efficacy at low concentrations in the inhibition of egg hatching and larval development of H. contortus. Although both extracts did not show consistent larvicidal action, the results were significant in inhibiting the oviposition of R. (B.) microplus engorged females
Achromobacter insolitus and zoogloea ramigera associated with wheat plants (triticum aestivum)
ARTIGO - Inglês
Assunto: Microscópio eletrônico
This study reports for the first time the presence of diazotrophic bacteria belonging to the genera Achromobacter and Zoogloea associated with wheat...
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This study reports for the first time the presence of diazotrophic bacteria belonging to the genera Achromobacter and Zoogloea associated with wheat plants. These bacterial strains were identified by the analysis of 16S rDNA sequences. The bacterium IAC-AT-8 was identified as Azospirillum brasiliense, whereas isolates IAC-HT-11 and IAC-HT-12 were identified as Achromobacter insolitus and Zoogloea ramigera, respectively. A greenhouse experiment involving a non-sterilized soil was carried out with the aim to study the endophytic feature of these strains. After 40 days from inoculation, all the strains were in the inner of roots, but they were not detected in soil. In order to assess the location inside wheat plants, an experiment was conducted under axenic conditions. Fifteen days after inoculation, preparations of inoculated plants were observed by the scanning electron microscope, using the cryofracture technique, and by the transmission electron microscope. It was observed that all isolates were present on the external part of the roots and in the inner part at the elongation region, in cortex cells, but not in the endodermis or in the vascular bundle region. No colonizing bacterial cells were observed in wheat leaves
Acmella oleracea and achyrocline satureioides as sources of natural products in topical wound care
ARTIGO - Inglês
Assunto: Ferimentos e lesões - Tratamento
The Brazilian forests have one of the world's biggest biodiversities. Achyrocline satureioides (macela) and Acmella oleracea (jambu) are native...
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The Brazilian forests have one of the world's biggest biodiversities. Achyrocline satureioides (macela) and Acmella oleracea (jambu) are native species from Brazil with a huge therapeutic potential, with proved anti-inflammatory and anesthetic action, respectively. The jambu's crude extract after depigmentation with activated charcoal and macela's essential oil were incorporated in a film made with hydroxyethyl cellulose. Those films were evaluated by mechanical test using a texturometer and anti-inflammatory and anesthetic activities by in vivo tests: wound healing and antinociceptive. The film containing the highest concentration of depigmented jambu's extract and macela's essential oil obtained an anesthesia time of 83.6 (+/- 28.5) min longer when compared with the positive control EMLA (R); the same occurred with the wound healing test; the film containing the highest concentration had a higherwound contraction (62.0%+/- 12.1) compared to the positive control allantoin and the histopathological analysis demonstrated that it increases collagen synthesis and epidermal thickening. The results demonstrate that the films have a potential use in skin wounds, pressure sore, and infected surgical wounds treatment
DOI: https://doi.org/10.1155/2016/3606820
Texto completo: https://www.hindawi.com/journals/ecam/2016/3606820
Actinobacteria from Antarctica as a source for anticancer discovery
ARTIGO - Inglês
Assunto: Biotecnologia
Although many advances have been achieved to treat aggressive tumours, cancer remains a leading cause of death and a public health problem worldwide....
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Although many advances have been achieved to treat aggressive tumours, cancer remains a leading cause of death and a public health problem worldwide. Among the main approaches for the discovery of new bioactive agents, the prospect of microbial secondary metabolites represents an effective source for the development of drug leads. In this study, we investigated the actinobacterial diversity associated with an endemic Antarctic species, Deschampsia antarctica, by integrated culture-dependent and culture-independent methods and acknowledged this niche as a reservoir of bioactive strains for the production of antitumour compounds. The 16S rRNA-based analysis showed the predominance of the Actinomycetales order, a well-known group of bioactive metabolite producers belonging to the Actinobacteria phylum. Cultivation techniques were applied, and 72 psychrotolerant Actinobacteria strains belonging to the genera Actinoplanes, Arthrobacter, Kribbella, Mycobacterium, Nocardia, Pilimelia, Pseudarthrobacter, Rhodococcus, Streptacidiphilus, Streptomyces and Tsukamurella were identified. The secondary metabolites were screened, and 17 isolates were identified as promising antitumour compound producers. However, the bio-guided assay showed a pronounced antiproliferative activity for the crude extracts of Streptomyces sp. CMAA 1527 and Streptomyces sp. CMAA 1653. The TGI and LC50 values revealed the potential of these natural products to control the proliferation of breast (MCF-7), glioblastoma (U251), lung/non-small (NCI-H460) and kidney (786-0) human cancer cell lines. Cinerubin B and actinomycin V were the predominant compounds identified in Streptomyces sp. CMAA 1527 and Streptomyces sp. CMAA 1653, respectively. Our results suggest that the rhizosphere of D. antarctica represents a prominent reservoir of bioactive actinobacteria strains and reveals it as an important environment for potential antitumour agents
ARTIGO - Inglês
Assunto: Hepatite C
Extracts from termite-associated bacteria were evaluated for in vitro antiviral activity against bovine viral diarrhea virus (BVDV). Two bacterial...
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Extracts from termite-associated bacteria were evaluated for in vitro antiviral activity against bovine viral diarrhea virus (BVDV). Two bacterial strains were identified as active, with percentages of inhibition (IP) equal to 98%. Both strains were subjected to functional analysis via the addition of virus and extract at different time points in cell culture; the results showed that they were effective as posttreatments. Moreover, we performed MTT colorimetric assays to identify the CC50, IC50, and SI values of these strains, and strain CDPA27 was considered the most promising. In parallel, the isolates were identified as Streptomyces through 16S rRNA gene sequencing analysis. Specifically, CDPA27 was identified as S. chartreusis. The CDPA27 extract was fractionated on a C18-E SPE cartridge, and the fractions were reevaluated. A 100% methanol fraction was identified to contain the compound(s) responsible for antiviral activity, which had an SI of 262.41. GC-MS analysis showed that this activity was likely associated with the compound(s) that had a peak retention time of 5 min. Taken together, the results of the present study provide new information for antiviral research using natural sources, demonstrate the antiviral potential of Streptomyces chartreusis compounds isolated from termite mounds against BVDV, and lay the foundation for further studies on the treatment of HCV infection
DOI: https://doi.org/10.1155/2015/745754
Texto completo: https://www.hindawi.com/journals/ecam/2015/745754/
Action of essential oils from brazilian native and exotic medicinal species on oral biofilms
ARTIGO - Inglês
Assunto: Atividade antimicrobiana
Essential oils (EO) obtained from twenty medicinal and aromatic plants were evaluated for their antimicrobial activity against the oral pathogens...
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Essential oils (EO) obtained from twenty medicinal and aromatic plants were evaluated for their antimicrobial activity against the oral pathogens Candida albicans, Fusobacterium nucleatum, Porphyromonas gingivalis, Streptococcus sanguis and Streptococcus mitis. The antimicrobial activity of the EO was evaluates by microdilution method determining Minimal Inhibitory Concentration. Chemical analysis of the oils compounds was performed by Gas chromatography-mass spectrometry (CG-MS). The most active EO were also investigated as to their actions on the biolfilm formation. The most of the essential oils (EO) presented moderate to strong antimicrobial activity against the oral pathogens (MIC--Minimal Inhibitory Concentrations values between 0.007 and 1.00 mg/mL). The essential oil from Coriandrum sativum inhibited all oral species with MIC values from 0.007 to 0.250 mg/mL, and MBC/MFC (Minimal Bactericidal/Fungicidal Concentrations) from 0.015 to 0.500 mg/mL. On the other hand the essential oil of C. articulatus inhibited 63.96% of S. sanguis biofilm formation. Through Scanning Eletronic Microscopy (SEM) images no changes were observed in cell morphology, despite a decrease in biofilm formation and changes on biofilm structure. Chemical analysis by Gas Chromatography-Mass Spectrometry (GC-MS) of the C. sativum essential oil revealed major compounds derivatives from alcohols and aldehydes, while Cyperus articulatus and Aloysia gratissima (EOs) presented mono and sesquiterpenes. In conclusion, the crude oil from C. articulatus exhibited the best results of antimicrobial activity e ability to control biofilm formation. The chemical analysis showed the presence of terpenes and monoterpenes such as a-pinene, a-bulnesene and copaene. The reduction of biofilms formation was confirmed from SEM images. The results of this research shows a great potential from the plants studied as new antimicrobial sources
ARTIGO - Inglês
Assunto: Desenvolvimento embrionário
Abstract: Rhipicephalus sanguineus (Latreille, 1806) presents medical importance, being the principal vector of Rickettsia conorii, the causative...
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Abstract: Rhipicephalus sanguineus (Latreille, 1806) presents medical importance, being the principal vector of Rickettsia conorii, the causative agent of Botonous fever, occurring in various regions of Europe and Africa. In the Americas, has been reported as a vector of Rickettsia rickettsii, the causative agent of Mountain Spotted Fever. It presents veterinary importance because is responsible by the transmission of zoonosis like babesiosis, ehrlichiosis, hepatozoonosis and others. The resistance that these ticks show to some of the active principles used in acaricides has risen wildly. In other hand, the use of herbal medicines has been outstanding recently. Among the advantages of phytotherapics that justify their use are synergistic effects of its components and easy degradation in the environment. In this scenario, Tagetes patula L. (Asteraceae) appears as a species with great biocide potential. The phytochemical investigation of T. patula has resulted in the isolation of several chemical constituents such as benzofurans, carotenoids, flavonoids and thiophenes. This study aimed to test the effect of the ethanolic extract obtained from aerial parts of T. patula against eggs of R. sanguineus by Egg hatchability test and to verify, for the first time, the action of this sample on ovary cells of engorged females submitted to the Adult Immersion Test. The extract was very effective, inhibiting egg hatching in 96.98% (±0.025) with LD50 = 6.312 mg/mL (4.064–8.497 mg/mL). Microscopic analysis of the structure of the ovaries showed significant morphological changes in the structure of oocytes II–V and pedicel cells, interfering directly in its normal embryogenesis, impairing or impeding the formation of healthy larvae, breaking the life cycle of this ticks in the beginning. Despite the difficulty to control adult populations of ticks, these findings are important and provide an alternative to disrupt development on the environment
ARTIGO - Inglês
Assunto: Diversidade microbiana
Water generated during oil exploration is chemically complex and contains high concentrations of ammonium and, in some cases, high salinity. The most...
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Water generated during oil exploration is chemically complex and contains high concentrations of ammonium and, in some cases, high salinity. The most common way to remove ammonium from effluent is a biological process, which can be performed by different routes and different groups of microorganisms. However, the presence of salts in the effluents could be an inhibiting factor for biological processes, interfering directly with treatment. This study aimed to evaluate changes in the profile of a microbial community involved in the process of ammonium removal when subjected to a gradual increase of salt (NaCl), in which the complete inhibition of the ammonium removal process occurred at 125 g L-1 NaCl. During the sludge acclimatization process, samples were collected and submitted to denaturing gradient gel electrophoresis (DGGE) and massive sequencing of the 16S ribosomal RNA (rRNA) genes. As the salt concentration increased in the reactor, a change in the microbial community was observed by the DGGE band profiles. As a result, there was a reduction in the presence of bacterial populations, and an increase in archaeal populations was found. The sequencing data suggested that ammonium removal in the reactor was carried out by different metabolic routes by autotrophic nitrifying bacteria, such as Nitrosococcus, Nitrosomonas, Nitrosovibrio, Nitrospira, and Nitrococcus; ammonium-oxidizing archaea Candidatus nitrosoarchaeum; ANAMMOX microorganisms, such as Candidatus brocadia, Candidatus kuenenia, and Candidatus scalindua; and microorganisms with the potential to be heterotrophic nitrifying, such as Paracoccus spp., Pseudomonas spp., Bacillus spp., Marinobacter sp., and Alcaligenes spp
ARTIGO - Inglês
Assunto: Diversidade microbiana
Abstract: Different molecular tools (PCR-DGGE, 16S rRNA high-throughput sequencing and sequencing of the bamA gene) were used to assess and compare...
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Abstract: Different molecular tools (PCR-DGGE, 16S rRNA high-throughput sequencing and sequencing of the bamA gene) were used to assess and compare the microbial diversity in a pilot-scale expanded granular sludge bed (EGSB) reactor used for the anaerobic co-digestion of commercial laundry wastewater and domestic sewage and subjected to increasing concentrations of linear alkylbenzene sulfonate (LAS). Using PCR-DGGE, a microbial stratification along the sludge bed of the reactor was observed. When analyzed using 16S rRNA gene sequencing, the samples exhibited high microbial diversity and richness, with the lowest Shannon index obtained for the highest concentration of surfactant. For the Bacteria domain, the genera Bellilinea, Syntrophus, Syntrophobacter, Cytophaga, Bacteroides and Synergistes were the most abundant, whereas for the Archaea domain, the genera Methanosaeta and Methanolinea were predominant. The Pseudomonas genus was the only genus that was predicted to be involved in all steps of surfactant degradation. Additionally, bamA gene sequencing indicated the presence of the species Syntrophorhabdus aromaticivorans, Desulfosarcina cetonica and Syntrophus aciditrophicus, which have genetic potential for the aromatic ring cleavage under anaerobic conditions. Therefore, despite the high toxicity of LAS under anaerobic conditions, the use of different molecular tools revealed the great diversity and richness of the microbial community from the granular biomass of the EGSB pilot reactor, indicating that a microbial consortium is necessary for complete LAS degradation. Additionally, the sequencing analysis of the bamA gene represents a step forward in the understanding of the core microbial community involved in aromatic ring cleavage for anaerobic digestion of real laundry wastewater, which may guide future studies
ARTIGO - Inglês
Assunto: Biodegradação
Gene and genome-centric approaches were applied to investigate the microbial taxonomic and metabolic diversity profiles from a lab-scale anaerobic...
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Gene and genome-centric approaches were applied to investigate the microbial taxonomic and metabolic diversity profiles from a lab-scale anaerobic reactor applied to laundry wastewater treatment with increasing concentrations of linear alkylbenzene sulfonate (LAS). Therefore, metagenomic analysis was carried out with reactor samples collected under three conditions, (i) Stage I, the reactor was fed with synthetic medium, (ii) Stage II, synthetic medium was replaced by diluted laundry wastewater with specific LAS loading rates (SLLRs) of 1.0 ± 0.3 mgLASgTVS−1d−1 and (iii) Stage III, SLLRs increased to 2.7 ± 0.7 mgLASgTVS−1d−1. Shotgun metagenomic sequencing was performed on an Illumina HiSeq 2 × 150 bp platform. Gene-centric analysis of each step of the metabolic pathway (fumarate addition, β-oxidation, ring cleavage and desulfonation) for anaerobic aromatic degradation showed eight over-representative genera (Achromobacter, Pelodictyon, Pseudomonas, Psychrobacter, Rhodococcus, Stenotrophomonas, Sulfurovum and Syntrophobacter), suggesting a microbial core with an important role in LAS biodegradation. Some of these genera were also recovered through a differential binning method, representing fifteen bacterial and one archaeal metagenome-assembled genomes (MAGs). Biodegradation pathway reconstruction of LAS using six MAGs unveiled the syntrophism for complete degradation of the LAS molecule. Only the MAGs with taxonomic annotation for Syntrophobacter showed genetic potential for fumarate addition, whereas in the ring cleavage, there was a predominance of genes in MAGs with taxonomic annotation for Pseudomonas fragi and Rhodococcus. This work represents the first report of genome-centric approach to study biological reactors applied in anionic surfactant degradation, contributing with detailed metabolic information of the key microbial actors in LAS degradation and opening perspectives for future biotechnological strategies aiming at bioaugmentation and/or biostimulation of indigenous microbial populations
Analysis of metabolite profiles of Saccharomyces cerevisiae strains suitable for butanol production
ARTIGO - Inglês
Assunto: Saccharomyces cerevisiae
Butanol has advantages over ethanol as a biofuel. Although butanol is naturally produced by some Clostridium species, clostridial fermentation has...
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Butanol has advantages over ethanol as a biofuel. Although butanol is naturally produced by some Clostridium species, clostridial fermentation has inherent characteristics that prevent its industrial application. Butanol-producing Saccharomyces cerevisiae strains may be a solution to this problem. The aim of this study was to evaluate the ability of wild-type and industrial Brazilian strains of S. cerevisiae to produce n-butanol using glycine as co-substrate and evaluate the relationship between the production of this alcohol and other metabolites in fermented broth. Of the 48 strains analyzed, 25 were able to produce n-butanol in a glycine-containing medium. Strains exhibited different profiles of n-butanol, isobutanol, ethanol, glycerol and acetic acid production. Some wild-type strains showed substantial n-butanol production capability, for instance UFMG-CM-Y267, which produced about 12.7mg/L of butanol. Although this concentration is low, it demonstrates that wild-type S. cerevisiae can synthesize butanol, suggesting that selection and genetic modification of this microorganism could yield promising results. The findings presented here may prove useful for future studies aimed at optimizing S. cerevisiae strains for butanol production
ARTIGO - Inglês
Assunto: Frutanos
Abstract: The species chosen in this study were Aldama filifolia (Sch. Bip. ex Baker) E.E.Schill. & Panero, A. linearifolia (Chodat) E.E.Schill. &...
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Abstract: The species chosen in this study were Aldama filifolia (Sch. Bip. ex Baker) E.E.Schill. & Panero, A. linearifolia (Chodat) E.E.Schill. & Panero, and A. trichophylla (Dusén) Magenta, which are morphologically very similar. Their representatives are perennial, cespitose herbs with an odoriferous resin and a xylopodium with tuberous adventitious roots. These species are from Cerrado areas and present seasonality of development. The aim of the present study was to provide anatomical features of the underground system of the aforementioned species and try to explain certain aspects of their environmental adaptation. Some of the structural characteristics observed in the Aldama species are new for the Asteraceae family, such as a secondary protective tissue similar to storied cork, the variation of cambial activity in A. filifolia, and the tuberisation process by division of the medullary parenchyma cells. The essential oil composition of the xylopodia and roots showed some differences among the species and allowed the identification of some compounds with biological properties. The underground system, which has gemmiferous ability and tuberised roots able to store inulin-type fructans, is related to the seasonality of growth and the adaptation of such plants to the environmental conditions of their habitat
ARTIGO - Inglês
Assunto: Monoterpenos
Recently, molecular analysis caused the South American Viguiera Kunth species to be transferred to Aldama La Llave. However, the circumscription has...
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Recently, molecular analysis caused the South American Viguiera Kunth species to be transferred to Aldama La Llave. However, the circumscription has not been established for certain of the South American species, including Aldama filifolia (Sch.Bip. ex Baker) E.E.Schill. & Panero, A. linearifolia (Chodat) E.E.Schill. & Panero and A. trichophylla (Dusén) Magenta (comb. nov.), which had previously been treated as synonyms because of their high similarity. Therefore, the present study aimed to evaluate the anatomy of the aerial organs, and the yield and chemical composition of the essential oils from these three species, to determine the differences among them and thereby assist in species distinction. The anatomical analysis identified characteristics unique to each species, which are primarily related to the position and occurrence of secretory structures. Histochemical analysis demonstrated that the glandular trichomes and the canals secrete lipophilic substances, which are characterised by the presence of essential oils. The analysis of these essential oils identified monoterpenes as their major constituent and allowed for the recognition of chemical markers for each species. The anatomical and chemical characteristics identified by the present study confirmed that the studied samples belong to three distinct taxa
DOI: https://doi.org/10.1071/BT12160
Texto completo: https://www.publish.csiro.au/bt/BT12160