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1.
ACS Appl Mater Interfaces ; 16(3): 3809-3818, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38211320

RESUMEN

Narrowband blue emitters are indispensable in achieving ultrahigh-definition OLED displays that satisfy the stringent BT 2020 standard. Hereby, a series of bis-tridentate Ir(III) complexes bearing electron-deficient imidazo[4,5-b]pyridin-2-ylidene carbene coordination fragments and 2,6-diaryloxy pyridine ancillary groups were designed and synthesized. They exhibited deep blue emission with quantum yields of up to 89% and a radiative lifetime of 0.71 µs in the DPEPO host matrix, indicating both the high efficiency and excellent energy transfer process from the host to dopant. The OLED based on Irtb1 showed an emission at 468 nm with a maximum external quantum efficiency (EQE) of 22.7%. Moreover, the hyper-OLED with Irtb1 as a sensitizer for transferring energy to terminal emitter v-DABNA exhibited a narrowband blue emission at 472 nm and full width at half-maximum (FWHM) of 24 nm, a maximum EQE of 23.5%, and EQEs of 19.7, 16.1, and 12.9% at a practical brightness of 100, 1000, and 5000 cd/m2, respectively.

2.
J Agric Food Chem ; 71(49): 19622-19637, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38014964

RESUMEN

A variety of active factors in milk and foods have been proven to serve as microbial nutrients that regulate the formation of early gut microbiota (GM), thereby ensuring the healthy development of infants. This study demonstrated that dietary nucleotides (NTs), one of the main nitrogen-containing substances in human milk, promoted the neurodevelopment of neonatal rats and the expression of Sox2, Dcx, Tuj1, and NeuN in the prefrontal cortex and hippocampus, but had no significant regulatory effects in the striatum. 16s rRNA sequencing and metabolomics of the colon contents of neonatal rats at different developmental stages showed that the early intake of NTs promoted an increase in the abundance of beneficial microorganisms related to neurodevelopment, digestion, and gut absorption, such as g_Romboutsia and g_Akkermansia. Changes in the ability of the GM to regulate folate synthesis, riboflavin metabolism, and other processes were also observed. Further analysis revealed significant correlations between the level of characteristic metabolites, namely, trans-3-indoleacrylic acid, urocanic acid, inosine, and adenosine, in the gut with neurodevelopment and characteristic GM components. These findings suggest that NTs in milk may affect neurodevelopment and maturation in early life by regulating the GM composition-gut-brain axis.


Asunto(s)
Microbioma Gastrointestinal , Ratas , Humanos , Animales , Eje Cerebro-Intestino , Animales Recién Nacidos , Nucleótidos , ARN Ribosómico 16S/genética , Leche Humana
3.
Quantum Front ; 2(1): 11, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37780230

RESUMEN

We study the nonlinear optical properties of heterojunctions made of graphene nanoribbons (GNRs) consisting of two segments with either the same or different topological properties. By utilizing a quantum mechanical approach that incorporates distant-neighbor interactions, we demonstrate that the presence of topological interface states significantly enhances the second- and third-order nonlinear optical response of GNR heterojunctions that are created by merging two topologically inequivalent GNRs. Specifically, GNR heterojunctions with topological interface states display third-order harmonic hyperpolarizabilities that are more than two orders of magnitude larger than those of their similarly sized counterparts without topological interface states, whereas the second-order harmonic hyperpolarizabilities exhibit a more than ten-fold contrast between heterojunctions with and without topological interface states. Additionally, we find that the topological state at the interface between two topologically distinct GNRs can induce a noticeable red-shift of the quantum plasmon frequency of the heterojunctions. Our results reveal a general and profound connection between the existence of topological states and an enhanced nonlinear optical response of graphene nanostructures and possible other photonic systems.

4.
Entropy (Basel) ; 25(3)2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36981318

RESUMEN

In wireless distributed computing systems, worker nodes connect to a master node wirelessly and perform large-scale computational tasks that are parallelized across them. However, the common phenomenon of straggling (i.e., worker nodes often experience unpredictable slowdown during computation and communication) and packet losses due to severe channel fading can significantly increase the latency of computational tasks. In this paper, we consider a heterogeneous, wireless, distributed computing system performing large-scale matrix multiplications which form the core of many machine learning applications. To address the aforementioned challenges, we first propose a random linear network coding (RLNC) approach that leverages the linearity of matrix multiplication, which has many salient properties, including ratelessness, maximum straggler tolerance and near-ideal load balancing. We then theoretically demonstrate that its latency converges to the optimum in probability when the matrix size grows to infinity. To combat the high encoding and decoding overheads of the RLNC approach, we further propose a practical variation based on batched sparse (BATS) code. The effectiveness of our proposed approaches is demonstrated by numerical simulations.

5.
RSC Adv ; 13(5): 3306-3316, 2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36756417

RESUMEN

This study investigated the effects of germination pretreatment on the physicochemical properties, lipid concomitants, and antioxidant activity of flaxseed oil in three varieties. The results indicated that the oil content of flaxseed decreased by 2.29-7.40% during the 5 days germination period. Germinated flaxseed oil showed a significantly higher acid value and lower peroxide value. The unsaturated fatty acid content was slightly increased by germination. Germination pretreatment resulted in significant increases in the α-tocopherol, stigmasterol, pigments, total phenols, and antioxidant activity. As germination time progressed to 5 days, α-tocopherol which was traditionally recognized as having the highest antioxidant activity form of vitamin E in humans increased from 3.07-6.82 mg kg-1 to 258.11-389.78 mg kg-1. Germinated oil had 1.63 to 2.05 times higher stigmasterol content than non-germinated oil. The chlorophyll and carotenoid also increased exponentially. The total phenol content of flaxseed oil increased from 64.29-75.85 mg kg-1 to 236.30-297.78 mg kg-1. Germinated flaxseed oil showed important antioxidant activity. Compared with other varieties during germination, the oil from Gansu showed a higher level of α-linolenic acid, tocopherols, and carotenoid, and a maximum increase level of tocopherols and phytosterols. The comprehensive evaluation of germination time by correlation and principal component analysis showed that when germination time exceeded 2 days, the lipid concomitants and antioxidant capacity of flaxseed oil were significantly improved.

6.
Crit Rev Food Sci Nutr ; 63(21): 4901-4915, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-34845958

RESUMEN

Edible oils are indispensable food components, because they are used for cooking or frying. However, during processing, transport, storage, and consumption, edible oils are susceptible to oxidation, during which various primary and secondary oxidative products are generated. These products may reduce the nutritional value and safety of edible oils and even harm human health. Therefore, analyzing the oxidation of edible oil is essential to ensure the quality and safety of oil. Oxidation is a complex process with various oxidative products, and the content of these products can be evaluated by corresponding indexes. According to the structure and properties of the oxidative products, analytical methods have been employed to quantify these products to analyze the oxidation of oil. Combined with proper chemometric analytical methods, qualitative identification has been performed to discriminate oxidized and nonoxidized oils. Oxidative products are complex and diverse. Thus, proper indexes and analytical methods should be selected depending on specific research objectives. Expanding the mechanism of the correspondence between oxidative products and analytical methods is crucial. The underlying mechanism, conventional indexes, and applications of analytical methods are summarized in this review. The challenges and perspectives for future applications of several methods in determining oxidation are also discussed. This review may serve as a reference in the selection, establishment, and improvement of methods for analyzing the oxidation of edible oil.HighlightsThe mechanism of edible oil oxidation analysis was elaborated.Conventional oxidation indexes and their limited values were discussed.Analytical methods for the determination of oxidative products and qualitative identification of oxidized and non-oxidized oils were reviewed.


Asunto(s)
Alimentos , Aceites , Humanos , Oxidación-Reducción , Valor Nutritivo , Culinaria , Aceites de Plantas/química
7.
Molecules ; 27(17)2022 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-36080489

RESUMEN

The effective reflective anode remains a highly desirable component for the fabrication of reliable top-emitting organic light-emitting diodes (TE-OLEDs) which have the potential to be integrated with complementary metal-oxide-semiconductor (CMOS) circuits for microdisplays. This work demonstrates a novel laminated anode consisting of a Cr/Al/Cr multilayer stack. Furthermore, we implement an ultra-thin titanium nitride (TiN) layer as a protective layer on the top of the Cr/Al/Cr composite anode, which creates a considerably reflective surface in the visible range, and meanwhile improves the chemical stability of the electrode against the atmosphere or alkali environment. Based on [2-(2-pyridinyl-N)phenyl-C](acetylacetonate)iridium(III) as green emitter and Mg/Ag as transparent cathode, our TE-OLED using the TiN-coated anode achieves the maximum current efficiency of 71.2 cd/A and the maximum power efficiency of 66.7 lm/W, which are 81% and 90% higher than those of the reference device without TiN, respectively. The good device performance shows that the Cr/Al/Cr/TiN could function as a promising reflective anode for the high-resolution microdisplays on CMOS circuits.

8.
Life Sci ; 304: 120719, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35716734

RESUMEN

BACKGROUND: More than 95 % of human diseases may be related to the disturbance of gut microbes. As a treatment method that extensively regulates the gut microbes, fecal microbiota transplantation (FMT) has proven to be an effective therapy for some diseases, becoming a topic of interest among clinicians, patients and scientists. AIM: To review the latest clinical research results of FMT in the treatment of various diseases and the methodology and risk management in clinical application. METHODS: Search PubMed and Web of Science for reliable research results of clinical treatment of FMT within 5-10 years, as well as application guidelines and risk management policies in different regions. RESULTS: As a measure of allogeneic/autologous microbiota transplantation, FMT has been used to treat a variety of diseases. By reviewing the clinical studies of FMT in gastrointestinal diseases, metabolic diseases, neurological diseases and malignant tumors, the various mechanisms in the treatment of diseases are summarized. Such as regulation of receptor microbiota composition, specific metabolites, phage function and immune response. In addition, potential risk factors, donor stool screening indicators, recipient self-specificity and possible prognostic marker molecules in the course of FMT treatment were generalized. CONCLUSIONS: The potential regulatory mechanisms, risk factors and targets of FMT in gastrointestinal diseases, metabolic diseases, malignancies and neurological diseases were reviewed and proposed. It provides a theoretical basis for the establishment of a standardized treatment system for FMT and a breakthrough in treatment technology.


Asunto(s)
Enfermedades Gastrointestinales , Enfermedades Metabólicas , Trasplante de Microbiota Fecal/métodos , Heces , Enfermedades Gastrointestinales/etiología , Enfermedades Gastrointestinales/terapia , Humanos , Enfermedades Metabólicas/etiología , Gestión de Riesgos , Resultado del Tratamiento
9.
J Gerontol A Biol Sci Med Sci ; 77(12): 2346-2355, 2022 12 29.
Artículo en Inglés | MEDLINE | ID: mdl-35352111

RESUMEN

Low skeletal muscle mass (SMM) is a crucial component of the sarcopenia phenotypes. In the present study, we aim to identify the specific metabolites associated with SMM variation and their functional mechanisms of decreased SMM in early postmenopausal women. We performed an untargeted metabolomics analysis in 430 early postmenopausal women to identify specific metabolite associated with skeletal muscle mass indexes (SMIes). Then, the potential causal effect of specific metabolite on SMM variation was accessed by one-sample Mendelian randomization (MR) analysis. Finally, in vitro experiments and transcriptomics bioinformatics analysis were conducted to explore the impact and potential functional mechanisms of specific metabolite on SMM variation. We detected 65 metabolites significantly associated with at least one SMI (variable importance in projection > 1.5 by partial least squares regression and p < .05 in multiple linear regression analysis). Remarkably, stearic acid (SA) was negatively associated with all SMIes, and subsequent MR analyses showed that increased serum SA level had a causal effect on decreased SMM (p < .05). Further in vitro experiments showed that SA could repress myoblast's differentiation at mRNA, protein, and phenotype levels. By combining transcriptome bioinformatics analysis, our study supports that SA may inhibit myoblast differentiation and myotube development by regulating the migration, adhesion, and fusion of myoblasts. This metabolomics study revealed specific metabolic profiles associated with decreased SMM in postmenopausal women, first highlighted the importance of SA in regulating SMM variation, and illustrated its potential mechanism on decreased SMM.


Asunto(s)
Músculo Esquelético , Sarcopenia , Femenino , Humanos , Pueblos del Este de Asia , Músculo Esquelético/fisiología , Posmenopausia , Análisis de la Aleatorización Mendeliana , Biología Computacional
10.
Biomed Pharmacother ; 149: 112831, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35303566

RESUMEN

Chlorogenic acid (CGA) is a phenolic compound that is widely distributed in honeysuckle, Eucommia, fruits and vegetables. It has various biological functions, including cardiovascular, nerve, kidney, and liver protection, and it exerts a protective effect on human health, according to clinical research and basic research. The intestine and brain are two important organs that are closely related in the human body. The intestine is even called the "second brain" in humans. However, among the many reports in the literature, an article systematically reporting the regulatory effects and specific mechanisms of CGA on the intestines and brain has not been published. In this context, this review uses the regulatory role and mechanism of CGA in the intestine and brain as the starting point and comprehensively reviews CGA metabolism in the body and the regulatory role and mechanism of CGA in the intestine and brain described in recent years. Additionally, the review speculates on the potential biological actions of CGA in the gut-brain axis. This study provides a scientific theory for CGA research in the brain and intestines and promotes the transformation of basic research and the application of CGA in food nutrition and health care.


Asunto(s)
Ácido Clorogénico , Eucommiaceae , Encéfalo , Ácido Clorogénico/farmacología , Humanos
11.
J Agric Food Chem ; 69(29): 8144-8159, 2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34260232

RESUMEN

Drinking tea has been proven to have a positive biological effect in regulating human glucose and lipid metabolism and preventing type 2 diabetes (T2D). Skeletal muscle (SkM) is responsible for 70% of the sugar metabolism in the human body, and its dysfunction is an important factor leading to the development of obesity, T2D, and muscle diseases. As one of the four known theaflavins (TFs) in black tea, the biological role of theaflavin (TF1) in regulating SkM metabolism has not been reported. In this study, mature myotubes induced by C2C12 cells in vitro were used as models. The results showed that TF1 (20 µM) promoted mitochondrial abundance and glucose absorption in myotubes by activating the CaMKK2-AMPK signaling axis via Ca2+ influx. Moreover, it promoted the expression of slow muscle fiber marker genes (Myh7, Myl2, Tnnt1, and Tnnc1) and PGC-1α/SIRT1, as well as enhanced the oxidative phosphorylation capacity of myotubes. In conclusion, this study preliminarily clarified the potential role of TF1 in regulating SkM glucose absorption as well as promoting SkM mitochondrial biosynthesis and slow muscle fiber formation. It has potential research and application values for the prevention/alleviation of SkM-related T2D and Ca2+-related skeletal muscle diseases through diet.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Diabetes Mellitus Tipo 2 , Biflavonoides , Calcio , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina/genética , Catequina , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/genética , Glucosa , Humanos , Fibras Musculares Esqueléticas , Músculo Esquelético
12.
J Nutr Biochem ; 93: 108619, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33705956

RESUMEN

Skeletal muscle (SkM) is essential for body movement, energy metabolism, and material metabolism, and directly influences the quality of human life. Aging, chronic diseases, and strenuous exercise often lead to various health problems associated with SkM, including muscle atrophy, loss of muscle mass and strength, and metabolic disorders. Various natural products (NaPs), mainly resveratrol (RES), quercetin (QUE), ursolic acid (UA), ecdysone (ECD; mainly 20-OH ECD, 20-HE), and vitamin D, have been reported to protect or regulate SkM health. Some of the products are functionally equivalent to sex hormones, and some are even referred to as "plant exercise pills." However, controversy persists regarding the role of NaPs in SkM health. Therefore, this review objectively summarizes the in vivo and vitro biological activities, molecular mechanisms, and clinical research results of studies on NaPs applied in the regulation of SkM health over the past decade. The present review could advance further research on NaPs and SkM health, and facilitate the revelation of new evidence that could facilitate the application of NaPs in ensuring SkM health.


Asunto(s)
Productos Biológicos/farmacología , Músculo Esquelético/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos , Homeostasis/efectos de los fármacos , Humanos , Mitocondrias Musculares/efectos de los fármacos , Mitocondrias Musculares/metabolismo
13.
Crit Rev Food Sci Nutr ; 61(2): 211-233, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32090598

RESUMEN

(-)-Epicatechin (EC) is a flavanol easily obtained through the diet and is present in tea, cocoa, vegetables, fruits, and cereals. Recent studies have shown that EC protects human health and exhibits prominent anti-oxidant and anti-inflammatory activities, enhances muscle performance, improves symptoms of cardiovascular and cerebrovascular diseases, prevents diabetes, and protects the nervous system. With the development of modern medical and biotechnology research, the mechanisms of action associated with EC toward various chronic diseases are becoming more apparent, and the pharmacological development and utilization of EC has been increasingly clarified. Currently, there is no comprehensive systematic introduction to the effects of EC and its mechanisms of action. This review presents the latest research progress and the role of EC in the prevention and treatment of various chronic diseases and its protective health effects and provides a theoretical basis for future research on EC.


Asunto(s)
Cacao , Catequina , Antiinflamatorios , Antioxidantes , Humanos , Polifenoles
14.
J Agric Food Chem ; 68(37): 9978-9992, 2020 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-32830510

RESUMEN

Aging and muscle diseases often lead to a decline in the differentiation capacity of myoblasts, which in turn results in the deterioration of skeletal muscle (SkM) function and impairment of regeneration ability after injury. Theaflavins, the "gold molecules" found in black tea, have been reported to possess various biological activities and have a positive effect on maintaining human health. In this study, we found that among the four theaflavins (theaflavin (TF1), theaflavin-3-gallate (TF2A), theaflavin-3'-gallate (TF2B), and theaflavin-3,3'-digallate (TF3) monomers), TF1 (20 µM) significantly promoted the fusion index of myoblasts, number of mature myotubes, and degree of myotube development. By combining transcriptomics, bioinformatics, and molecular biology experiments, we showed that TF1 may promote myoblast differentiation by (1) regulating the withdrawal of myoblasts from the cell cycle, inducing the release of myogenic factors (MyoD, MyoG, and MyHC) and accelerating myogenic differentiation and (2) regulating the adhesion force of myoblasts and mechanical properties of mature myotubes and promoting the migration, fusion, and development of myoblasts. In conclusion, our study outcomes show that TF1 can promote myoblast differentiation and regulate myotube mechanical properties. It is a potential dietary supplement for the elderly. Our findings provide a new scientific basis for the relationship between tea drinking and aging.


Asunto(s)
Biflavonoides/farmacología , Camellia sinensis/química , Catequina/farmacología , Desarrollo de Músculos/efectos de los fármacos , Mioblastos/citología , Mioblastos/efectos de los fármacos , Extractos Vegetales/farmacología , Animales , Biflavonoides/química , Fenómenos Biomecánicos , Catequina/química , Ciclo Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Línea Celular , Movimiento Celular/efectos de los fármacos , Ratones , Fibras Musculares Esqueléticas/química , Fibras Musculares Esqueléticas/citología , Fibras Musculares Esqueléticas/efectos de los fármacos , Mioblastos/química , Extractos Vegetales/química
15.
J Nutr Biochem ; 74: 108225, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31629963

RESUMEN

Muscle degeneration and cachexia caused by aging and chronic diseases seriously reduce the quality of life of patients. Catechins in tea enhance skeletal muscle performance, but the specific function and mechanism require further exploration. Myogenic differentiation is accompanied by extensive changes in cell morphology and gene expression patterns. In this study, we measured the number, length, diameter, and transcriptional levels of MyoD, MyoG, and MyHC of myotubes after C2C12 cell differentiation to assess changes in response to four different catechin monomers: epicatechin, epigallocatechin, epicatechin gallate (ECG), and epigallocatechin gallate. The differentiation-promoting effect of ECG was the strongest. Atomic force microscopy showed that ECG significantly reduced the adhesion force, stiffness, and Young's modulus of myotubes. Finally, the mechanism of ECG-enhanced C2C12 cell differentiation was explored by a LC/MS whole proteomic strategy and Ingenuity Pathway Analysis. The results provide a powerful basis for further study of catechin-enhanced skeletal muscle regeneration and repair.


Asunto(s)
Catequina/farmacología , Diferenciación Celular/efectos de los fármacos , Músculo Esquelético/citología , Animales , Catequina/análogos & derivados , Diferenciación Celular/fisiología , Línea Celular , Módulo de Elasticidad , Regulación de la Expresión Génica/efectos de los fármacos , Ratones , Microscopía de Fuerza Atómica , Fibras Musculares Esqueléticas/química , Fibras Musculares Esqueléticas/citología , Fibras Musculares Esqueléticas/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Proteína MioD/genética , Mioblastos Esqueléticos/citología , Mioblastos Esqueléticos/efectos de los fármacos , Mioblastos Esqueléticos/metabolismo , Miogenina/genética
16.
Molecules ; 24(9)2019 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-31058847

RESUMEN

Due to changes in the dietary structure of individuals, the incidence of digestive tract tumors has increased significantly in recent years, causing a serious threat to the life and health of patients. This has in turn led to an increase in cancer prevention research. Many studies have shown that epigallocatechin-3-gallate (EGCG), an active ingredient in green tea, is in direct contact with the digestive tract upon ingestion, which allows it to elicit a significant antagonizing effect on digestive tract tumors. The main results of EGCG treatment include the prevention of tumor development in the digestive tract and the induction of cell cycle arrest and apoptosis. EGCG can be orally administered, is safe, and combats other resistances. The synergistic use of cancer drugs can promote the efficacy and reduce the anti-allergic properties of drugs, and is thus, favored in medical research. EGCG, however, currently possesses several shortcomings such as poor stability and low bioavailability, and its clinical application prospects need further development. In this paper, we have systematically summarized the research progress on the ability of EGCG to antagonize the activity and mechanism of action of digestive tract tumors, to achieve prevention, alleviation, delay, and even treat human gastrointestinal tract tumors via exogenous dietary EGCG supplementation or the development of new drugs containing EGCG.


Asunto(s)
Catequina/análogos & derivados , Ciclo Celular/efectos de los fármacos , Neoplasias Gastrointestinales/tratamiento farmacológico , Administración Oral , Disponibilidad Biológica , Catequina/administración & dosificación , Catequina/farmacocinética , Catequina/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Descubrimiento de Drogas , Humanos , Té/química
18.
Int J Syst Evol Microbiol ; 66(1): 178-183, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26476707

RESUMEN

A Gram-stain-negative, rod-shaped, aerobic and non-motile strain, designated 4-T-34T, was isolated from a till sample of Collins icecap front, Antarctica, and its taxonomic position was investigated by genotypic, phenotypic and chemotaxonomic analysis. The isolate grew at 4-30 °C (optimum 20-25 °C), at pH 6.0-10.0 and with 0-1.0 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 4-T-34T belonged to the genus Pseudorhodobacter, with the closest relatives being Pseudorhodobacter wandonensis WT-MW11T (96.9 % 16S rRNA gene sequence similarity), Pseudorhodobacter antarcticus ZS3-33T (96.8 %), Pseudorhodobacter ferrugineus IAM 12616T (96.5 %) and Pseudorhodobacter aquimaris HDW-19T (95.4 %). Strain 4-T-34T contained Q-10 as the only ubiquinone and C18 : 1ω7c as the major fatty acid. The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, two unidentified aminophospholipids and two unidentified phospholipids. The DNA G+C content of strain 4-T-34T was 61 mol%. On the basis of phylogenetic, physiological and chemotaxonomic data, strain 4-T-34T is considered to represent a novel species of the genus Pseudorhodobacter, for which the name Pseudorhodobacter collinsensis sp. nov. is proposed. The type strain is 4-T-34T ( = CCTCC AB 2014005T = LMG 28256T).


Asunto(s)
Cubierta de Hielo/microbiología , Filogenia , Rhodobacteraceae/clasificación , Regiones Antárticas , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Datos de Secuencia Molecular , Fosfolípidos/química , ARN Ribosómico 16S/genética , Rhodobacteraceae/genética , Rhodobacteraceae/aislamiento & purificación , Análisis de Secuencia de ADN , Ubiquinona/análogos & derivados , Ubiquinona/química
19.
Int J Syst Evol Microbiol ; 66(1): 172-177, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26475320

RESUMEN

A novel rod-shaped, Gram-stain-negative, non-gliding and aerobic strain surrounded by a multilayer capsule, designated 4-T-2T, was isolated from a till sample of Collins glacier front, Antarctica. The bacterium formed yellow, circular, convex and smooth colonies. Growth occurred at 4-28 °C (optimum18-20 °C), at pH 7.0-10.0 (optimum pH 9.0) and with 0-1 % NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 4-T-2T belonged to the genus Flavobacterium. Strain 4-T-2T shared the highest 16S rRNA gene sequence similarity with the type strain of Flavobacterium algicola (96.7 %). The DNA G+C content of strain 4-T-2T was 36.2 mol%. The only menaquinone was MK-6. The major cellular fatty acids were iso-C15 : 0, iso-C15 : 1 G, iso-C16 : 0 and summed feature 9 (comprising iso-C17 : 1ω9c and/or 10-methyl C16 : 0). Polar lipid profile consisted phosphatidylethanolamine, one unidentified aminolipid, one unidentified aminophospholipid and one unidentified lipid. On the basis of phylogenetic, physiological and chemotaxonomic data, strain 4-T-2T is considered to represent a novel species of the genus Flavobacterium, for which the name Flavobacterium collinsense sp. nov. is proposed. The type strain is 4-T-2T ( = CCTCC AB 2014004T = LMG 28257T).


Asunto(s)
Flavobacterium/clasificación , Cubierta de Hielo/microbiología , Filogenia , Regiones Antárticas , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Flavobacterium/genética , Flavobacterium/aislamiento & purificación , Datos de Secuencia Molecular , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
20.
Int J Syst Evol Microbiol ; 66(3): 1218-1223, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26702622

RESUMEN

A novel psychrotolerant bacterium, designed strain M6-79T, was isolated from an arctic glacial foreland soil sample collected from Ny-Ålesund in the Svalbard Archipelago, Norway. Cells of strain M6-79T were Gram-stain-negative, rod-shaped and produced a red-pigment. Strain M6-79T was strictly aerobic, non-motile, non-endospore-forming, oxidase-negative and catalase-positive. Based on 16S rRNA gene sequence analysis, strain M6-79T was phylogenetically related to Roseomonas aquatica TR53T (95.2 % 16S rRNA gene sequence similarity), Roseomonas lacus TH-G33T (94.3 %), 'Roseomonas sediminicola' FW-3 (94.3 %), Roseomonas terrae DS-48T (94.1 %) and Roseomonas soli 5N26T (94.1 %). The unique isoprenoid quinone detected in strain M6-79T was Q-9. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, one unknown aminolipid and one unknown lipid. Strain M6-79T possessed C18 : 1ω7c, C16 : 0 and summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c) as the predominant fatty acids, and the DNA G+C content was 71.2 mol%. Combined data from phylogenetic, phenotypic and chemotaxonomic studies revealed that strain M6-79T represents a novel species of the genus Roseomonas, for which the name Roseomonas arctica sp. nov. is proposed. The type strain is strain M6-79T ( = CCTCC AB 2013101T = LMG 28251T).

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