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1.
Environ Monit Assess ; 196(4): 339, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38436740

RESUMEN

Forests are pivotal in upholding and stabilizing ecosystem functions and services globally. Assessing changes in forest cover serves as a crucial indicator to comprehend the scope, scale, and dynamics of land use and land cover alterations on regional and global scales. This study evaluates the forest cover changes between 2005 and 2021, pinpointing the key drivers of forest land changes within the Senan district in Ethiopia's Amhara region. The analysis incorporated Landsat satellite images from 2005, 2011, and 2021, supplemented by field surveys using questionnaire data. Results reveal a shift: forest cover declined from 13.6% (2005) to 11.2% (2011) but rose to 15.4% by 2021, averaging a 12.9% annual change. Several crucial factors were identified as contributors to this forest cover change. These include expanding agricultural land, population growth, urbanization, and using wood as a fuel source. Poverty, exacerbated by population growth, climate change impacts, and a scarcity of food resources, directly linked to a shortage of farmlands, emerged as significant drivers of forest cover change. In light of these findings, an in-depth analysis of land use and land cover dynamics should be conducted, particularly at the expense of forest lands. Moreover, implementing sustainable management practices by developing strategies for intensive agriculture and fostering environmentally friendly non-farm income-generating activities is essential. This study provides reference material to policymakers and land-use planners setting sustainable development goals, advocating for balanced economic growth and environmental conservation to foster a harmonious relationship between humans and forests.


Asunto(s)
Ecosistema , Monitoreo del Ambiente , Humanos , Etiopía , Bosques , Madera
2.
Appl Environ Microbiol ; 88(13): e0075422, 2022 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-35703553

RESUMEN

Methyltransferases transfer a methyl group to a diverse group of natural products, thus providing structural diversity, stability, and altered pharmacological properties to the molecules. A limited number of regiospecific sugar-O-methyltransferases are functionally characterized. Thus, discovery of such an enzyme could solve the difficulties of biological production of methoxy derivatives of glycosylated molecules. In the current study, a regiospecific sugar-O-methyltransferase, ThnM1, belonging to the biosynthetic gene cluster (BGC) of 1-(α-L-(2-O-methyl)-6-deoxymannopyranosyloxy)-3,6,8-trimethoxynaphthalene produced by Nocardia sp. strain CS682, was analyzed and functionally characterized. ThnM1 demonstrated promiscuity to diverse chemical structures such as rhamnose-containing anthraquinones and flavonoids with regiospecific methylation at the 2'-hydroxyl group of the sugar moiety. Compared with other compounds, anthraquinone rhamnosides were found to be the preferred substrates for methylation. Thus, the enzyme was further employed for whole-cell biotransformation using engineered Escherichia coli to produce a methoxy-rhamnosyl derivative of quinizarin, an anthraquinone derivative. The structure of the newly generated derivative from Escherichia coli fermentation was elucidated by liquid chromatography-mass spectrometry and nuclear magnetic resonance spectroscopic analyses and identified as quinizarin-4-O-α-l-2-O-methylrhamnoside (QRM). Further, the biological impact of methylation was studied by comparing the cytotoxicity of QRM with that of quinizarin against the U87MG, SNU-1, and A375SM cancer cell lines. IMPORTANCE ThnM1 is a putative sugar-O-methyltransferase produced by the Nocardia sp. strain CS682 and is encoded by a gene belonging to the biosynthetic gene cluster (BGC) of 1-(α-l-(2-O-methyl)-6-deoxymannopyranosyloxy)-3,6,8-trimethoxynaphthalene. We demonstrated that ThnM1 is a promiscuous enzyme with regiospecific activity at the 2'-OH of rhamnose. As regiospecific methylation of sugars by chemical synthesis is a challenging step, ThnM1 may fill the gap in the potential diversification of natural products by methylating the rhamnose moiety attached to them.


Asunto(s)
Productos Biológicos , Nocardia , Productos Biológicos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Metiltransferasas/metabolismo , Nocardia/genética , Nocardia/metabolismo , Ramnosa/metabolismo , Azúcares/metabolismo
3.
Biotechnol Appl Biochem ; 69(4): 1723-1732, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34415071

RESUMEN

Epothilone A, a microtubule-stabilizing agent used as therapeutics for the treatment of cancers, was biotransformed into three metabolites using Nocardia sp. CS692 and recombinant Nocardia overexpressing a cytochrome P450 from Streptomyces venezuelae (PikC). Among three metabolites produced in the biotransformation reaction mixtures, ESI/MS2 analysis predicted two metabolites (M1 and M2) as novel hydroxylated derivatives (M1 is hydroxylated at the C-8 position and M2 is hydroxylated at C-10 position), each with an opened-epoxide ring in their structure. Interestingly, metabolite M3 lacks an epoxide ring and is known as deoxyepothilone A, which is also called epothilone C. Metabolite M1 was produced only in PikC overexpressing strain. The endogenous enzymes of Nocardia sp. catalyzed hydroxylation of epothilone A to produce metabolite M2 and removed epoxide ring to produce metabolite M3. All the metabolites were identified based on UV-vis analysis and rigorous ESI/MS2 fragmentation based on epothilone A standard. The newly produced metabolites are anticipated to display novel cytotoxic effects and could be subjects of further pharmacological studies.


Asunto(s)
Nocardia , Biotransformación , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Epotilonas , Compuestos Epoxi , Humanos , Nocardia/genética , Nocardia/metabolismo
4.
Biotechnol Appl Biochem ; 69(2): 848-861, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33797804

RESUMEN

Taxifolin (dihydroquercetin) and its derivatives are medicinally important flavanonols with a wide distribution in plants. These compounds have been isolated from various plants, such as milk thistle, onions, french maritime, and tamarind. In general, they are commercially generated in semisynthetic forms. Taxifolin and related compounds are biosynthesized via the phenylpropanoid pathway, and most of the biosynthetic steps have been functionally characterized. The knowledge gained through the detailed investigation of their biosynthesis has provided the foundation for the reconstruction of biosynthetic pathways. Plant- and microbial-based platforms are utilized for the expression of such pathways for generating taxifolin-related compounds, either by whole-cell biotransformation or through reconfiguration of the genetic circuits. In this review, we summarize recent advances in the biotechnological production of taxifolin and its derivatives.


Asunto(s)
Quercetina , Silybum marianum , Antioxidantes/química , Flavonoides , Silybum marianum/genética , Silybum marianum/metabolismo , Quercetina/análogos & derivados , Quercetina/química
5.
Appl Microbiol Biotechnol ; 105(12): 5023-5037, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34136924

RESUMEN

Streptomyces sp. KCTC 0041BP, which was isolated from a soil sample in Cheolwon, Republic of Korea, is a dihydrochalcomycin producer. In this study, we obtained the genome of S. sp. KCTC 0041BP with 7.54 Mb genome size. antiSMASH and the dbCAN2 meta server predicted that the genome would contain 26 secondary metabolite biosynthetic gene clusters (BGCs) and 285 carbohydrate-active enzymes. Besides dihydrochalcomycin, 21 compounds were successfully identified from S. sp. KCTC 0041BP, and among them, the structure of 8 compounds were proven by high-resolution electrospray ionization mass spectrometry (HRESIMS) and nuclear magnetic resonance (NMR). The identification of chalcomycin analogs led to a better understanding of the biosynthetic pathway of dihydrochalcomycin/chalcomycin. From the analysis of cluster 2 and solvent selection, linearmycins were determined. Linearmycins showed antibacterial activity with both Gram-positive and Gram-negative bacteria and antifungal activity. One strain many compounds (OSMAC) strategy was applied to activate the salicylic acid production in this strain. A salicylic acid biosynthetic pathway was also predicted, but not by antiSMASH. These results showed that this strain can produce many useful compounds and potentially produce novel compounds with most secondary BGCs yet to be experimentally identified.


Asunto(s)
Streptomyces , Antibacterianos , Glicósidos , Bacterias Gramnegativas , Bacterias Grampositivas , Macrólidos , Familia de Multigenes , República de Corea , Streptomyces/genética
6.
J Am Chem Soc ; 142(18): 8074-8079, 2020 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-32294387

RESUMEN

We developed a new optical method to determine the rate of reverse intersystem crossing (krISC) in thermally activated delayed fluorescent (TADF) organic chromophores using time-resolved transient absorption spectroscopy. We successfully correlated the krISC of the TADF-chromophores with device performance. Specifically, we focused on the external quantum efficiency (ηEQE) and the stability of the device at high brightness levels. It is believed that by obtaining a large krISC one may reduce the possibility of triplet-triplet annihilation (TTA) and increase the long-term stability of organic light emitting diodes (OLEDs) devices at high brightness levels (ηEQE roll-off). In this contribution, we investigate the photophysical mechanism in a series of TADF-chromophores based on carbazole or acridine derivatives as donor moieties, and triazine or benzonitrile derivatives as the acceptor moieties. We found a relationship between large krISC values and high ηEQE values at low operating voltages for the TADF-chromophores investigated. In addition, those chromophores with a larger krISC illustrated a smaller ηEQE roll-off (higher stability) at high operating voltages. These features are beneficial for superior OLEDs performing devices. Contrarily, we found that if a chromophore has a krISC ≤ 105s-1 its ηEQE is ≤5%. Such a small krISC suggests that there is no TADF effect operating in these organic systems and the molecule is not efficient in harvesting triplet excitons. Emission lifetime-based methodologies for determining the krISC were included for comparison but failed to predict the devices performance of the investigated TADF-chromophores to the same extent of our proposed methodology.

7.
Appl Microbiol Biotechnol ; 104(2): 713-724, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31820068

RESUMEN

Zincphyrin IV is a potential organic photosensitizer which is of significant interest for applications in biomedicine, materials science, agriculture (as insecticide), and chemistry. Most studies on Zincphyrin are focused on Zincphyrin III while biosynthesis and application of Zincphyrin IV is comparatively less explored. In this study, we explored Zincphyrin IV production in Streptomyces venezuelae ATCC 15439 through combination of morphology engineering and "One strain many compounds" approach. The morphology engineering followed by change in culture medium led to activation of cryptic Zincphyrin IV biosynthetic pathway in S. venezuelae with subsequent detection of Zincphyrin IV. Morphology engineering applied in S. venezuelae increased the biomass from 7.17 to 10.5 mg/mL after 48 h of culture. Moreover, morphology of engineered strain examined by SEM showed reduced branching and fragmentation of mycelia. The distinct change in color of culture broth visually demonstrated the activation of the cryptic biosynthetic pathway in S. venezuelae. The production of Zincphyrin IV was found to be initiated after overexpression ssgA, resulting in the increase in titer from 4.21 to 7.54 µg/mL. Furthermore, Zincphyrin IV demonstrated photodynamic antibacterial activity against Bacillus subtilis and photodynamic anticancer activity against human ovarian carcinoma cell lines.


Asunto(s)
Antibacterianos/biosíntesis , Antineoplásicos/metabolismo , Coproporfirinas/biosíntesis , Ingeniería Metabólica/métodos , Fármacos Fotosensibilizantes/metabolismo , Streptomyces/crecimiento & desarrollo , Streptomyces/metabolismo , Antibacterianos/farmacología , Antineoplásicos/farmacología , Bacillus subtilis/efectos de los fármacos , Vías Biosintéticas/genética , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Fenómenos Químicos , Coproporfirinas/farmacología , Medios de Cultivo/química , Humanos , Microscopía Electrónica de Rastreo , Fármacos Fotosensibilizantes/farmacología , Streptomyces/genética , Streptomyces/ultraestructura
8.
Nanotechnology ; 29(11): 115203, 2018 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-29328054

RESUMEN

To improve the classification accuracy of an image data set (CIFAR-10) by using analog input voltage, synapse devices with excellent conductance linearity (CL) and multi-level cell (MLC) characteristics are required. We analyze the CL and MLC characteristics of TaOx-based filamentary resistive random access memory (RRAM) to implement the synapse device in neural network hardware. Our findings show that the number of oxygen vacancies in the filament constriction region of the RRAM directly controls the CL and MLC characteristics. By adopting a Ta electrode (instead of Ti) and the hot-forming step, we could form a dense conductive filament. As a result, a wide range of conductance levels with CL is achieved and significantly improved image classification accuracy is confirmed.


Asunto(s)
Conductividad Eléctrica , Redes Neurales de la Computación , Óxidos/química , Reconocimiento de Normas Patrones Automatizadas , Tantalio/química
9.
Acc Chem Res ; 49(11): 2424-2434, 2016 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-27753477

RESUMEN

All-polymer solar cells (all-PSCs), consisting of conjugated polymers as both electron donor (PD) and acceptor (PA), have recently attracted great attention. Remarkable progress has been achieved during the past few years, with power conversion efficiencies (PCEs) now approaching 8%. In this Account, we first discuss the major advantages of all-PSCs over fullerene-polymer solar cells (fullerene-PSCs): (i) high light absorption and chemical tunability of PA, which affords simultaneous enhancement of both the short-circuit current density (JSC) and the open-circuit voltage (VOC), and (ii) superior long-term stability (in particular, thermal and mechanical stability) of all-PSCs due to entangled long PA chains. In the second part of this Account, we discuss the device operation mechanism of all-PSCs and recognize the major challenges that need to be addressed in optimizing the performance of all-PSCs. The major difference between all-PSCs and fullerene-PSCs originates from the molecular structures and interactions, i.e., the electron transport ability in all-PSCs is significantly affected by the packing geometry of two-dimensional PA chains relative to the electrodes (e.g., face-on or edge-on orientation), whereas spherically shaped fullerene acceptors can facilitate isotropic electron transport properties in fullerene-PSCs. Moreover, the crystalline packing structures of PD and PA at the PD-PA interface greatly affect their free charge carrier generation efficiencies. The design of PA polymers (e.g., main backbone, side chain, and molecular weight) should therefore take account of optimizing three major aspects in all-PSCs: (1) the electron transport ability of PA, (2) the molecular packing structure and orientation of PA, and (3) the blend morphology. First, control of the backbone and side-chain structures, as well as the molecular weight, is critical for generating strong intermolecular assembly of PA and its network, thus enabling high electron transport ability of PA comparable to that of fullerenes. Second, the molecular orientation of anisotropically structured PA should be favorably controlled in order to achieve efficient charge transport as well as charge transfer at the PD-PA interface. For instance, face-to-face stacking between PD and PA at the interface is desired for efficient free charge carrier generation because misoriented chains often cause an additional energy barrier for overcoming the binding energy of the charge transfer state. Third, large-scale phase separation often occurs in all-PSCs because of the significantly reduced entropic contribution by two macromolecular chains of PD and PA that energetically disfavors mixing. In this Account, we review the recent progress toward overcoming each recognized challenge and intend to provide guidelines for the future design of PA. We believe that by optimization of the parameters discussed above the PCE values of all-PSCs will surpass the 10% level in the near future and that all-PSCs are promising candidates for the successful realization of flexible and portable power generators.

10.
Int J Syst Evol Microbiol ; 67(8): 3117-3121, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28771125

RESUMEN

A Gram-stain-negative, aerobic, oxidase-positive, catalase-positive and rod-shaped bacterium designated strain 3R17T was isolated from freshwater. Strain 3R17T produced bright-yellow, circular, convex and smooth colonies on R2A agar, tryptic soy agar, potato dextrose agar, nutrient agar and brain-heart infusion agar media. The strain was motile by gliding. The strain grew at 4-30 °C (optimum, 25 °C), at pH 6-9 (optimum, pH 7) and in the presence of up to 3 % NaCl (optimum, 0 %) on R2A agar. The 16S rRNA gene sequence analysis indicated that 3R17T represents a member of the genus Flavobacterium and is most closely related to Flavobacterium resistens BD-b365T, with a sequence similarity of 97.78 %, but the strain formed a distinct phylogenetic lineage of its own. Fatty acid analysis indicated that a summed feature comprising C16 : 1ω7c and/or C16 : 1ω6c, iso-C15 : 0, iso-C15 : 1G, anteiso-C15 : 0, C16 : 0, iso-C17 : 0 3-OH and iso-C15 : 0 3-OH were the major components (>5 %). Strain 3R17T contained phosphatidylethanolamine (PE) and several unidentified aminolipids as main polar lipids, and MK-6 as the predominant isoprenoid quinone. Flexirubin pigments were not produced. The DNA G+C content was 35.4 mol%. The combination of physiological and chemotaxonomic properties distinguished 3R17T from related species of the genus Flavobacterium. On the basis of polyphasic taxonomy, 3R17T evidently represents a novel species within the genus Flavobacterium, for which the name Flavobacterium fluminis sp. nov. is proposed. The type strain is 3R17T (=KCTC 42062T=JCM 30338T).


Asunto(s)
Flavobacterium/clasificación , Agua Dulce/microbiología , Filogenia , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Flavobacterium/genética , Flavobacterium/aislamiento & purificación , Fosfatidiletanolaminas/química , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
11.
Int J Syst Evol Microbiol ; 66(8): 3230-3234, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27222401

RESUMEN

A Gram-stain-negative, motile by gliding, non-spore-forming and oval-shaped bacterial strain designated T1-10T was isolated from pine forest soil, and its taxonomic position was investigated using a polyphasic approach. Growth occurred at 10-37 °C (optimum, 30 °C), at pH 6-7 and in the presence of 0-1 % (w/v) (optimum, 0 %) NaCl. Flexirubin-type pigments were produced. On the basis of 16S rRNA gene sequence similarity, strain T1-10T was assigned to the genus Taibaiella of the phylum Bacteroidetes, and the most closely related species was Taibaiella koreensis THG-DT86T with 97.11 % sequence similarity, but the strain formed an independent lineage in the phylogenetic tree. The genomic DNA G+C content of strain T1-10T was 42.5 mol%. The main cellular fatty acids were iso-C15 : 1 G, iso-C15 : 0 and iso-C17 : 0 3-OH. The only isoprenoid quinone detected in the strain was MK-7, and the major polyamine was homospermidine. The major polar lipids were phosphatidylethanolamine and unidentified aminophospholipids. Strain T1-10T could be distinguished from related species by physiological and biochemical properties. Phenotypic and phylogenetic data supported that strain T1-10T represents a novel species of the genus Taibaiella, for which the name Taibaiella soli sp. nov. is proposed (type strain T1-10T=KCTC 42277T=JCM 31014T).


Asunto(s)
Bacteroidetes/clasificación , Bosques , Filogenia , Pinus/microbiología , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , Bacteroidetes/genética , Bacteroidetes/aislamiento & purificación , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Fosfatidiletanolaminas , Fosfolípidos/química , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN , Espermidina/química , Vitamina K 2/análogos & derivados , Vitamina K 2/química
12.
Int J Syst Evol Microbiol ; 66(1): 201-205, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26498187

RESUMEN

A Gram-stain-negative, non-spore-forming and coccus-shaped bacterial strain, designated 4DR5T, was isolated from freshwater and its taxonomic position was investigated using a polyphasic approach. Growth occurred at 10-40 °C (optimum 30 °C), at pH 6-9 (optimum pH 7) and in the presence of 0-0.4 % (w/v) NaCl (optimum 0 %) on R2A agar. On the basis of 16S rRNA gene sequence similarity, strain 4DR5T was assigned to the family Moraxellaceae of the class Gammaproteobacteria, and its closest related taxa were species of the genera Perlucidibaca (93.67 % sequence similarity), Agitococcus (93.07 %), Paraperlucidibaca (92.31-92.38 %), Alkanindiges (91.79 %) and Acinetobacter (90.24-91.23 %). The predominant isoprenoid quinone detected in strain 4DR5T was Q-10. The major cellular fatty acids were a summed feature consisting of C16 : 1ω7c and/or C16 : 1ω6c, one consisting of C18 : 1ω7c and/or C18 : 1ω6c, and C16 : 0. The major polar lipid was phosphatidylethanolamine. The genomic DNA G+C content of the strain was 61.2 mol%. The phylogenetic, chemotaxonomic and biochemical data not only supported the affiliation of strain 4DR5T to the family Moraxellaceae, but also separated it from other established genera within the family. Therefore, the novel isolate evidently represents a novel species of a new genus of Moraxellaceae, for which the name Fluviicoccus keumensis gen. nov., sp. nov. is proposed. The type strain of Fluviicoccus keumensis is 4DR5T ( = KCTC 32475T = JCM 19370T).


Asunto(s)
Agua Dulce/microbiología , Moraxellaceae/clasificación , Filogenia , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Datos de Secuencia Molecular , Moraxellaceae/genética , Moraxellaceae/aislamiento & purificación , Fosfatidiletanolaminas/química , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN , Ubiquinona/análogos & derivados , Ubiquinona/química
13.
Int J Syst Evol Microbiol ; 66(4): 1823-1827, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26842896

RESUMEN

A novel actinobacterium designated strain MWE-A11T was isolated from the root of wild Artemisia princeps (mugwort). The isolate was aerobic, Gram-stain-positive and short rod-shaped, and the colonies were yellow and circular with entire margin. Strain MWE-A11T grew at 15-37 °C and pH 6.0-8.0. The predominant isoprenoid quinones were MK-11 and MK-10. The predominant fatty acids were anteiso-C15:0 and iso-C16:0, and the DNA G+C content was 68.8 mol%. The main polar lipids were diphosphatidylglycerol, phosphatidylglycerol and an unidentified glycolipid. The peptidoglycan contained 2,4-diaminobutyric acid as the diagnostic diamino acid, and the acyl type was glycolyl. Phylogenetic analyses based on 16S rRNA gene sequence comparisons indicated that strain MWE-A11T was affiliated with the family Microbacteriaceae, and was most closely related to the type strains of Humibacter antri (96.4% 16S rRNA gene sequence similarity), Herbiconiux moechotypicola (96.3%), Leifsonia soli (96.3%), Leifsonia lichenia (96.2%), Leifsonia xyli subsp. cynodontis (96.1%), Microbacterium testaceum (96.0%) and Humibacter albus (96.0%). However, the combination of chemotaxonomic properties clearly distinguished strain MWE-A11T from the related taxa at genus level. Accordingly, Allohumibacter endophyticus gen. nov., sp. nov. is proposed to accommodate a new member of the family Microbacteriaceae. The type strain of the type species is MWE-A11T (=JCM 19371T=KCTC 29232T).


Asunto(s)
Actinomycetales/clasificación , Artemisia/microbiología , Filogenia , Actinomycetales/genética , Actinomycetales/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Glucolípidos/química , Datos de Secuencia Molecular , Peptidoglicano/química , Fosfolípidos/química , Raíces de Plantas/microbiología , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN , Vitamina K 2/química
14.
Int J Syst Evol Microbiol ; 66(1): 365-370, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26530258

RESUMEN

A Gram-stain-negative, motile by gliding, yellow-pigmented bacterial strain, designated KNUS1T, was isolated from Lake Paro in Korea. The phylogenetic tree based on 16S rRNA gene sequences showed that strain KNUS1T formed a distinct lineage within the genus Flavobacterium. Strain KNUS1T was closely related to Flavobacterium cheonhonense ARSA-15T (96.8 %16S rRNA gene sequence similarity), Flavobacterium pectinovorum DSM 6368T (96.3 %) and Flavobacterium dankookense ARSA-19T (96.1 %). The major fatty acids of strain KNUS1T were iso-C15 : 0 and iso-C15 : 1 G. The major polyamine was sym-homospermidine. The major polar lipids of strain KNUS1T were phosphatidylethanolamine, five unidentified aminolipids and three unidentified polar lipids. The major respiratory'quinone was menaquinone 6 (MK-6). The DNA G+C content of strain KNUS1T was 34.2 mol%. On the basis of the evidence presented in this study, strain KNUS1T represents a novel species of the genus Flavobacterium, for which the name Flavobacterium paronense sp. nov. is proposed. The type strain is KNUS1T ( = KACC 17692T = CECT 8460T).


Asunto(s)
Flavobacterium/clasificación , Agua Dulce/microbiología , Filogenia , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Flavobacterium/genética , Flavobacterium/aislamiento & purificación , Islas , Datos de Secuencia Molecular , Fosfolípidos/química , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN , Espermidina/análogos & derivados , Espermidina/química , Vitamina K 2/análogos & derivados , Vitamina K 2/química
15.
Nutr Neurosci ; 19(7): 318-26, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24856006

RESUMEN

OBJECTIVES: Since oils and fats can induce metabolic syndrome, leading to cardiovascular and cerebrovascular diseases, the present study was performed to find out whether the plant oils affect the cerebral hemorrhage in stroke-prone spontaneously hypertensive (SHR-SP) rats. METHODS: From 47 days of age, male SHR-SP rats were given drinking water containing 1% NaCl to induce hypertension, and simultaneously fed semi-purified diets containing 10% perilla oil, canola oil, or shortening. The onset time of convulsion following cerebral hemorrhage was recorded, and the areas of hemorrhage and infarction were analyzed in the stroke brains. RESULTS: In comparison with 58-day survival of SHR-SP rats during feeding NaCl alone, perilla oil extended the survival time to 68.5 days, whereas canola oil shortened it to 45.7 days. Feeding perilla oil greatly reduced the total volume of cerebral hemorrhage from 17.27% in the control group to 4.53%, while shortening increased the lesions to 21.23%. In a microscopic analysis, perilla oil also markedly decreased the hemorrhagic and infarction lesions to 1/10 of those in control rats, in contrast to an exacerbating effect of shortening. In blood analyses, perilla oil reduced blood total cholesterol and low-density lipoproteins which were increased in SHR-SP, but canola oil further increased them and markedly lowered platelet counts. DISCUSSION: Perilla oil delayed and attenuated cerebral hemorrhage by improving hyperlipidemia in hypertensive stroke animals, in contrast to the aggravating potential of canola oil and shortening. It is suggested that perilla oil should be the first choice oil for improving metabolic syndrome in hypertensive persons at risk of hemorrhagic stroke.


Asunto(s)
Hemorragia Cerebral/prevención & control , Grasas Insaturadas en la Dieta/uso terapéutico , Hiperlipidemias/dietoterapia , Hipertensión/dietoterapia , Aceites de Plantas/uso terapéutico , Accidente Cerebrovascular/prevención & control , Ácido alfa-Linolénico/uso terapéutico , Animales , Encéfalo/patología , Hemorragia Cerebral/sangre , Hemorragia Cerebral/etiología , Hemorragia Cerebral/patología , Grasas de la Dieta/efectos adversos , Grasas Insaturadas en la Dieta/efectos adversos , Ácidos Grasos Omega-3/efectos adversos , Ácidos Grasos Omega-3/uso terapéutico , Hiperlipidemias/sangre , Hiperlipidemias/etiología , Hiperlipidemias/fisiopatología , Hipertensión/sangre , Hipertensión/etiología , Hipertensión/fisiopatología , Riñón/patología , Masculino , Síndrome Metabólico/sangre , Síndrome Metabólico/dietoterapia , Síndrome Metabólico/etiología , Síndrome Metabólico/fisiopatología , Neuronas/patología , Aceites de Plantas/efectos adversos , Recuento de Plaquetas , Distribución Aleatoria , Aceite de Brassica napus , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Cloruro de Sodio Dietético/efectos adversos , Accidente Cerebrovascular/sangre , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/patología , Análisis de Supervivencia , Trombocitopenia/etiología , Ácido alfa-Linolénico/efectos adversos
16.
Regul Toxicol Pharmacol ; 78: 53-8, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27112419

RESUMEN

In Alzheimer disease (AD), amyloid-beta (Aß) peptides induce the degeneration of presynaptic cholinergic system, in which decreased activity of enzyme choline acetyltransferase (ChAT) responsible for acetylcholine synthesis is observed. Cereboost™, an extract of American ginseng extract, contains a high concentration of Rb1 ginsenoside which is a well-known ingredient improving human cognitive function. We investigated the effects of Cereboost™ on learning and memory function of mice challenged with an Aß1-42 peptide and the underlying mechanisms in vitro. Cereboost™ protected against Aß1-42-induced cytotoxicity in F3.ChAT stem cells, and enhanced the ChAT gene expression. Aß1-42 injection into the mouse brain impaired the cognitive function, which was recovered by oral administration of Cereboost™. In addition, Cereboost™ restored brain microtubule-associated protein 2 and synaptophysin as well as acetylcholine concentration. The results demonstrate that Cereboost™ administration recovered the cognitive function of AD model animals by enhancing acetylcholine level via ChAT gene expression and neuroprotection.


Asunto(s)
Acetilcolina/metabolismo , Enfermedad de Alzheimer/prevención & control , Conducta Animal/efectos de los fármacos , Encéfalo/efectos de los fármacos , Colina O-Acetiltransferasa/metabolismo , Cognición/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Panax/química , Extractos Vegetales/farmacología , Acetilcolinesterasa/metabolismo , Enfermedad de Alzheimer/inducido químicamente , Enfermedad de Alzheimer/enzimología , Enfermedad de Alzheimer/psicología , Péptidos beta-Amiloides , Animales , Reacción de Prevención/efectos de los fármacos , Encéfalo/enzimología , Línea Celular , Colina O-Acetiltransferasa/genética , Inhibidores de la Colinesterasa/aislamiento & purificación , Inhibidores de la Colinesterasa/farmacología , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Proteínas Ligadas a GPI/antagonistas & inhibidores , Proteínas Ligadas a GPI/metabolismo , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratones Endogámicos ICR , Proteínas Asociadas a Microtúbulos/metabolismo , Fármacos Neuroprotectores/aislamiento & purificación , Fragmentos de Péptidos , Fitoterapia , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales , Sinaptofisina/metabolismo , Factores de Tiempo , Transfección , Regulación hacia Arriba
17.
Int J Syst Evol Microbiol ; 65(8): 2717-2725, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25977281

RESUMEN

Two Gram-staining-positive, aerobic, endospore-forming, motile bacteria, strains DT7-4T and DLE-12T, were isolated from roots of evening primrose (Oenothera biennis) and day lily (Hemerocallis fulva), respectively, and subjected to taxonomic characterization. Analysis of 16S rRNA gene sequences indicated that the two strains fell into two distinct phylogenetic clusters belonging to the genus Paenibacillus. Strain DT7-4T was most closely related to Paenibacillus phyllosphaerae PALXIL04T and Paenibacillus taihuensis THMBG22T, with 96.3% 16S rRNA gene sequence similarity to each, and strain DLE-12T was most closely related to Paenibacillus ginsengarvi Gsoil 139T and Paenibacillus hodogayensis SGT, with 96.6 and 93.3% sequence similarity, respectively. Both isolates contained anteiso-C15 : 0 as the dominant fatty acid, meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan and MK-7 as the respiratory menaquinone. The cellular polar lipids were composed of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and unidentified polar lipids. The DNA G+C contents of strains DT7-4T and DLE-12T were 50.1 ± 0.7 and 55.2 ± 0.5 mol%, respectively. The chemotaxonomic properties of both isolates were typical of members of the genus Paenibacillus. However, our biochemical and phylogenetic analyses distinguished each isolate from related species. Based on our polyphasic taxonomic analysis, strains DT7-4T and DLE-12T should be recognized as representatives of novel species of Paenibacillus, for which the names Paenibacillus oenotherae sp. nov. (type strain DT7-4T = KCTC 33186T = JCM 19573T) and Paenibacillus hemerocallicola sp. nov. (type strain DLE-12T = KCTC 33185T = JCM 19572T) are proposed.


Asunto(s)
Hemerocallis/microbiología , Oenothera/microbiología , Paenibacillus/clasificación , Filogenia , Raíces de Plantas/microbiología , Composición de Base , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Paenibacillus/genética , Paenibacillus/aislamiento & purificación , Peptidoglicano/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
18.
Int J Syst Evol Microbiol ; 65(12): 4863-4867, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26443022

RESUMEN

A Gram-stain-negative, yellow, motile by gliding, filamentous bacterium, designated SR 2-06T, was isolated from surface-sterilized root of garden cosmos. 16S rRNA gene sequence analysis indicated that SR 2-06T was related most closely to Filimonas lacunae YT21T of the family Chitinophagaceae at a sequence similarity of 96.90 %, while levels of similarity to other related taxa were less than 93.08 %. Strain SR 2-06T exhibited similar features to F. lacunae in that it contained MK-7 as the major respiratory quinone, and iso-C15 : 1 G, iso-C15 : 0 and a summed feature consisting of C16 : 1ω6c and/or C16 : 1ω7c as the major fatty acids. However, strain SR 2-06T was distinguished from F. lacunae using a combination of physiological and biochemical properties. The cellular polar lipids were phosphatidylethanolamine, unknown aminophospholipids, unknown aminolipids, an unknown phospholipid and unidentified polar lipids. The DNA G+C content was 46.0 mol%. The phenotypic and phylogenetic evidence clearly indicates that strain SR 2-06T represents a novel species of the genus Filimonas, for which the name Filimonas endophytica sp. nov. is proposed. The type strain is SR 2-06T ( = KCTC 42060T = JCM 19844T).


Asunto(s)
Asteraceae/microbiología , Bacteroidetes/clasificación , Filogenia , Técnicas de Tipificación Bacteriana , Bacteroidetes/genética , Bacteroidetes/aislamiento & purificación , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Datos de Secuencia Molecular , Fosfolípidos/química , Pigmentación , Raíces de Plantas/microbiología , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
19.
Antonie Van Leeuwenhoek ; 107(1): 47-53, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25318449

RESUMEN

A proteobacterial strain designated R1-3(T) was isolated from indoor air of a pharmaceutical environment. Cells were Gram-stain-negative, oxidase- and catalase-positive, aerobic, motile and rod-shaped. Strain R1-3(T) grew optimally at pH 7, 30 °C and in 0-2 % NaCl on R2A agar. The 16S rRNA gene sequence analysis indicated that strain R1-3(T) belongs to the genus Sphingomonas, and is closely related to Sphingomonas paucimobilis ATCC 29837(T) (98.4 % sequence similarity). However, the DNA-DNA relatedness between the two strains was 43 ± 5 % (reciprocal = 37 ± 3 %), which was well below the suggested level for species distinction. Sphingomonas yabuuchiae GTC868(T) (97.7 % 16S rRNA gene sequence similarity) and Sphingomonas pseudosanguinis G1-2(T) (97.6 %) were also found as distantly related taxa. Strain R1-3(T) was sensitive to most of the tested antibiotics except for erythromycin and streptomycin. The major fatty acid was a summed feature consisting of C18:1 ω7c and/or C18:1 ω6c, and minor proportions of C14:0 2-OH, C16:0 and a summed feature consisting of C16:1 ω7c and/or C16:1 ω6c were also present. The DNA G + C content was 67.2 ± 1.0 mol%. The major polyamines were sym-homospermidine and spermidine. The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, and minor amounts of a sphingoglycolipid, a phospholipid, an aminoglycolipid and an unidentified lipid were also present. The phenotypic, phylogenetic and chemotaxonomic data not only supported the affiliation of strain R1-3(T) to the genus Sphingomonas, but also distinguished R1-3(T) from related species. On the basis of physiological, chemotaxonomic and phylogenetic evidences, strain R1-3(T) clearly merits recognition as a novel species of Sphingomonas, for which the name Sphingomonas aeria sp. nov. is proposed. The type strain is R1-3(T) (= KCTC 42061(T) = JCM 19859(T)).


Asunto(s)
Microbiología del Aire , Sphingomonas/clasificación , Sphingomonas/aislamiento & purificación , Aerobiosis , Antibacterianos/farmacología , Técnicas de Tipificación Bacteriana , Composición de Base , Análisis por Conglomerados , Citosol/química , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Industria Farmacéutica , Ácidos Grasos/análisis , Locomoción , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Fosfolípidos/análisis , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Cloruro de Sodio/metabolismo , Espermidina/análisis , Sphingomonas/genética , Sphingomonas/fisiología , Temperatura
20.
Bioprocess Biosyst Eng ; 38(9): 1645-53, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25924967

RESUMEN

Lignocellulases from Armillaria gemina and Pholiota adiposa are efficient in hydrolyzing aspen and poplar biomass, respectively. In the present study, lignocellulosic enzymes obtained from a fungal consortium comprising P. adiposa and A. gemina were used for the saccharification of sunflower stalks. Sunflower stalks were thermochemically pretreated using 2 % NaOH at 50 °C for 24 h. The saccharification process parameters including substrate concentration, enzyme loading, pH, and temperature were optimized using response surface methodology to improve the saccharification yield. The highest enzymatic hydrolysis (84.3 %) was obtained using the following conditions: enzyme loading 10 FPU/g-substrate, substrate 5.5 %, temperature 50 °C, and pH 4.5. The hydrolysis yield obtained using the enzymes from the fungal consortium was equivalent to that obtained using a mixture of commercial enzymes Celluclast and Novozyme ß-glucosidase. Addition of up to 500 ppm of heavy metal ions (As, Cu, Fe, Mn, Ni, Pb, and Zn) during saccharification did not significantly affect the saccharification yield. Thus, the biomass grown for phytoremediation of heavy metals can be used for the production of reducing sugars followed by ethanol fermentation.


Asunto(s)
Armillaria/enzimología , Carbohidratos/síntesis química , Celulasa/química , Helianthus/química , Lignina/química , Pholiota/enzimología , Carbohidratos/aislamiento & purificación , Consorcios Microbianos/fisiología , Tallos de la Planta/química
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