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1.
Crit Rev Food Sci Nutr ; 63(21): 4901-4915, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34845958

RESUMO

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.


Assuntos
Alimentos , Óleos , Humanos , Oxirredução , Valor Nutritivo , Culinária , Óleos de Plantas/química
2.
Entropy (Basel) ; 25(3)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36981318

RESUMO

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.

3.
Molecules ; 27(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36080489

RESUMO

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.

4.
Crit Rev Food Sci Nutr ; 61(2): 211-233, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32090598

RESUMO

(-)-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.


Assuntos
Cacau , Catequina , Anti-Inflamatórios , Antioxidantes , Humanos , Polifenóis
5.
Molecules ; 24(9)2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-31058847

RESUMO

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.


Assuntos
Catequina/análogos & derivados , Ciclo Celular/efeitos dos fármacos , Neoplasias Gastrointestinais/tratamento farmacológico , Administração Oral , Disponibilidade Biológica , Catequina/administração & dosagem , Catequina/farmacocinética , Catequina/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Descoberta de Drogas , Humanos , Chá/química
6.
Int J Syst Evol Microbiol ; 66(1): 178-183, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26476707

RESUMO

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).


Assuntos
Camada de Gelo/microbiologia , Filogenia , Rhodobacteraceae/classificação , Regiões Antárticas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Dados de Sequência Molecular , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Rhodobacteraceae/genética , Rhodobacteraceae/isolamento & purificação , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
7.
Int J Syst Evol Microbiol ; 66(1): 172-177, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26475320

RESUMO

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).


Assuntos
Flavobacterium/classificação , Camada de Gelo/microbiologia , Filogenia , Regiões Antárticas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacterium/genética , Flavobacterium/isolamento & purificação , Dados de Sequência Molecular , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
8.
Int J Syst Evol Microbiol ; 66(3): 1218-1223, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26702622

RESUMO

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).

9.
Int J Syst Evol Microbiol ; 65(Pt 1): 260-266, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25336722

RESUMO

A pale yellow, aerobic bacterium, strain M0-2(T), was isolated from a till sample. Its taxonomic position was investigated by using a polyphasic approach. Cells were Gram-stain-negative, rod-shaped and motile. Cells reproduced by budding or asymmetrical cell division. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain M0-2(T) belonged to the family Sphingomonadaceae and was closely related to species of the genera Novosphingobium (96.4-92.0%) and Blastomonas (94.6%), Sphingopyxis witflariensis W-50(T) (94.0%), Sphingosinicella soli KSL-125(T) (93.6%) and Sphingomonas astaxanthinifaciens TDMA-17(T) (93.5%). Ubiquinone-10 (Q-10) was the predominant respiratory quinone. The major fatty acids were summed feature 8 (comprising C18:1ω7c and/or C18:1ω6c, 31.9%), summed feature 3 (comprising C16:1ω7c and/or C16:1ω6c, 19.8%) and C14:0 2-OH (8.9%). Sphingoglycolipid, phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and phosphatidylcholine were the major polar lipids. Spermidine was the major polyamine observed in the cell. The genomic DNA G+C content was 47.5 mol%. On the basis of phylogenetic relationships and the low DNA G+C content compared with most other genera of the family Sphingomonadaceae, combined with phenotypic and chemotaxonomic data, strain M0-2(T) is considered to represent a novel species in a new genus in the family Sphingomonadaceae for which the name Parablastomonas arctica gen. nov., sp. nov. is proposed. The type strain of Parablastomonas arctica gen. nov., sp. nov. is M0-2(T) ( =CCTCC AB 2012968(T) = NRRL B-59110(T)).


Assuntos
Filogenia , Microbiologia do Solo , Sphingomonadaceae/classificação , Regiões Árticas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Camada de Gelo , Dados de Sequência Molecular , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espermidina/química , Sphingomonadaceae/genética , Sphingomonadaceae/isolamento & purificação , Svalbard , Ubiquinona/química
10.
Int J Syst Evol Microbiol ; 65(8): 2615-2621, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25951861

RESUMO

Strain M-SA3-94T, an aerobic, Gram-stain-positive, ovoid- to rod-shaped, non-motile bacterium, was isolated from the marine sediment of Ardley cove, King George Island, Antarctica. Strain M-SA3-94T grew optimally at pH 5.0-6.0, 20 °C and in the presence of 1.0 % (w/v) NaCl. Phylogenetic analysis, based on 16S rRNA gene sequences, indicated that strain M-SA3-94T belonged to the genus Nocardioides in the family Nocardioidaceae, clustering with Nocardioides plantarum NCIMB 12834T, Nocardioides ginsengagri BX5-10T, Nocardioides marinquilinus CL-GY44T and Nocardioides lianchengensis D94-1T (with 96.1 %, 95.9 %, 94.5 % and 94.7 % 16S rRNA gene sequence similarity, respectively). The chemotaxonomic properties of strain M-SA3-94T were similar to those of members of the genus Nocardioides with validly published names. The major fatty acid was iso-C16 : 0. The polar lipid pattern contained diphosphatidylglycerol, phosphatidylglycerol and three unknown phospholipids. The diagnostic diamino acid in the cell-wall peptidoglycan was ll-2, 6-diaminopimelic acid. MK-8(H4) was the predominant menaquinone and the DNA G+C content of this strain was 66.7 mol%. On the basis of these phenotypic, phylogenetic and chemotaxonomic data, strain M-SA3-94T represents a novel species of the genus Nocardioides, for which the name Nocardioides antarcticus sp. nov. is proposed. The type strain is M-SA3-94T ( = CCTCC AB2014053T = LMG 28254T).


Assuntos
Actinomycetales/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Actinomycetales/genética , Actinomycetales/isolamento & purificação , Regiões Antárticas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Dados de Sequência Molecular , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
11.
Int J Syst Evol Microbiol ; 65(7): 2326-2333, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25872958

RESUMO

A pale yellow, ovoid- to rod-shaped and budding bacterium, designated strain M-S13-148(T), was isolated from a decayed bone of whale from the eastern coast of King George Island, South Shetlands, Antarctica. Strain M-S13-148(T) exhibited motility, aerobic growth and was Gram-stain-negative. Strain M-S13-148(T) was positive for catalase and oxidase. Growth was observed at pH 6.0-9.0, at 4-42 °C and with 0-14% (w/v) NaCl. The novel strain contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine and an unknown phospholipid as the major polar lipids. The dominant cellular fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), (58.8%) and C16 : 0 (11.7%). The respiratory quinone was Q-10 and the DNA G + C content was 60.9 mol%. Neighbour-joining, maximum-likelihood and minimum-evolution phylogenetic trees, based on 16S rRNA gene sequences, indicated that strain M-S13-148(T) belonged to the genus Roseovarius and was most closely related to Roseovarius nanhaiticus CCTCC AB 208317(T) (93.72% 16S rRNA gene sequence similarity). The 16S rRNA gene sequence similarity with respect to members of the genus Roseovarius ranged from 91.81 to 93.94%. On the basis of phenotypic, molecular and chemotaxonomic characteristics, strain M-S13-148 is considered to represent a novel species of the genus Roseovarius, for which the name Roseovarius antarcticus sp. nov., is proposed. The type strain is M-S13-148(T) ( = CCTCC AB2014072(T) = LMG 28420(T)).


Assuntos
Osso e Ossos/microbiologia , Filogenia , Rhodobacteraceae/classificação , Baleias/microbiologia , Animais , Regiões Antárticas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Dados de Sequência Molecular , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Rhodobacteraceae/genética , Rhodobacteraceae/isolamento & purificação , Análise de Sequência de DNA , Ubiquinona/química
12.
Int J Syst Evol Microbiol ; 64(Pt 5): 1817-1824, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24556636

RESUMO

A novel pink-pigmented, facultatively methylotrophic strain, designated M6-76T, was isolated from glacial foreland soil near Ny-Ålesund, Svalbard Archipelago, Norway. Cells of strain M6-76T were rod-shaped (0.4-0.7×0.8-2.0 µm), Gram-stain-negative, aerobic and motile by a single polar flagellum. Growth occurred at 4-28 °C (optimum 18 °C) and at pH 5-8 (optimum pH 7). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain M6-76T belonged to the family Methylobacteriaceae. The 16S rRNA gene sequence of the novel strain showed 94.6%, 94.0% and 93.9% sequence similarity to those of Methylobacterium salsuginis MRT, Methylobacterium organophilum ATCC 27886T and Microvirga subterranea FaiI4T, respectively. Cells could utilize methanol as the sole source of carbon and energy but not formate. The major respiratory quinone was Q-10. The polar lipids were phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine and two unknown polar lipids. The predominant cellular fatty acids were summed feature 8 (C18:1ω7c and/or C18:1ω6c), summed feature 3 (C16:1ω6c and/or C16:1ω7c) and C16:0. The DNA G+C content was 67 mol%. The polyphasic data presented in this study indicated that the isolate should be classified as representing a novel species of a new genus within the family Methylobacteriaceae. The name Psychroglaciecola arctica gen. nov., sp. nov. is therefore proposed for the isolate. The type strain of the type species is M6-76T (=CCTCC AB 2013033T=KACC 17684T).


Assuntos
Methylobacteriaceae/classificação , Filogenia , Microbiologia do Solo , Regiões Árticas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Methylobacteriaceae/genética , Methylobacteriaceae/isolamento & purificação , Dados de Sequência Molecular , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Svalbard , Ubiquinona/química
13.
Int J Syst Evol Microbiol ; 64(Pt 6): 2113-2118, 2014 06.
Artigo em Inglês | MEDLINE | ID: mdl-24676732

RESUMO

A novel, red-pink-pigmented strain, designated R2-4(T), was isolated from a till sample near Ny-Alesund, Svalbard Archipelago, Norway. Cells were aerobic, Gram-stain-negative and rod-shaped. Growth occurred at 4-30 °C (optimum, 20-22 °C), at pH 6.0-9.0 (optimum, pH 7.0) and with 0-1% NaCl added to R2A agar. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain R2-4(T) belonged to the genus Hymenobacter. 16S rRNA gene sequence similarity between strain R2-4(T) and the type strains of related species of the genus ranged from 94.51 to 96.05%. Strain R2-4(T) contained iso-C(15 : 0), anteiso-C(15 : 0), summed feature 3 (C(16 : 1)ω6c and/or C(16 : 1)ω7c), summed feature 4 (C(17 : 1) anteiso B and/or iso I) and C(16 : 1)ω5c as the major cellular fatty acids, MK-7 as the major respiratory quinone, and phosphatidylethanolamine, unknown aminophospholipids, unknown aminolipids and unknown lipids as the main polar lipids. The polyamine was sym-homospermidine. The DNA G+C content of strain R2-4(T) was 61.6 mol%. On the basis of phylogenetic, physiological and chemotaxonomic data, strain R2-4(T) is considered to represent a novel species of the genus Hymenobacter, for which the name Hymenobacter arcticus sp. nov. is proposed. The type strain is R2-4(T) ( = CCTCC AB 2012104(T) = KACC 16881(T)).


Assuntos
Cytophagaceae/classificação , Camada de Gelo/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , Cytophagaceae/genética , Cytophagaceae/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Dados de Sequência Molecular , Fosfatidiletanolaminas/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espermidina/análogos & derivados , Espermidina/química , Svalbard , Vitamina K 2/análogos & derivados , Vitamina K 2/química
14.
Int J Syst Evol Microbiol ; 64(Pt 7): 2233-2237, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24711591

RESUMO

A novel orange-pigmented strain, designated R2-35(T), was isolated from a glacier till near Ny-Alesund, Svalbard Archipelago, Norway. The cells were aerobic, Gram-negative, rod-shaped and sometimes filamentous. Growth occurred at 4-28 °C (optimum, 20 °C), at pH 7.0-9.0 (optimum, pH 8.0) and with 0-1% NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain R2-35(T) belonged to the genus Spirosoma with sequence similarity to related species ranging from 91.65 to 95.19%. Strain R2-35(T) contained C16 : 0 (10.7%), C18 : 0 (9.2%), C16 : 1ω5c (16.5%) and summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c) (24.6%) as the major cellular fatty acids, MK-7 as the major respiratory quinone, and phosphatidylethanolamine as the main polar lipid. The DNA G+C content of strain R2-35(T) was 54.9 mol%. On the basis of phylogenetic, physiological and chemotaxonomic data, strain R2-35(T) is considered to represent a novel species of the genus Spirosoma, for which the name Spirosoma arcticum sp. nov., is proposed, The type strain is R2-35(T) ( = CCTCC AB 2012849(T) = LMG 28141(T)).


Assuntos
Cytophagaceae/classificação , Camada de Gelo , Filogenia , Microbiologia do Solo , Regiões Árticas , Técnicas de Tipagem Bacteriana , Composição de Bases , Cytophagaceae/genética , Cytophagaceae/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Dados de Sequência Molecular , Fosfatidiletanolaminas/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Svalbard , Vitamina K 2/análogos & derivados , Vitamina K 2/química
15.
Int J Syst Evol Microbiol ; 64(Pt 7): 2431-2436, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24763603

RESUMO

Two psychrotolerant, Gram-stain-negative, rod-shaped bacterial strains, designed M1-27(T) and 8-24(T), were subjected to polyphasic taxonomic studies. Strain M1-27(T) was isolated from the foreland of the Midtre Lovénbreen glacier, whereas strain 8-24(T) was isolated from the foreland of the Austre Lovénbreen glacier. Both were Arctic glacier forelands, near Ny-Ålesund, Svalbard Archipelago, Norway. Strains M1-27(T) and 8-24(T) exhibited 16S rRNA gene sequence similarities of 91.0-96.0% and 92.3-96.7%, respectively, to type strains of recognized species of the genus Pedobacter. Phylogenetic analysis based on 16S rRNA gene sequences showed that the two strains were grouped with members of the genus Pedobacter, but represented distinct taxa. Both strains contained MK-7 as the predominant menaquinone. The DNA G+C contents of strains M1-27(T) and 8-24(T) were 43.8% and 39.4%, respectively. The phenotypic characteristics, biochemical properties and polygenetic analysis, clearly indicated that strains M1-27(T) ( = CCTCC AB 2012936(T) = LMG 28205(T)) and 8-24(T) ( = CCTCC AB 2012941(T) = NRRL B-59993(T)) represent two novel species of the genus Pedobacter, for which the names Pedobacter huanghensis sp. nov. and Pedobacter glacialis sp. nov., respectively, are proposed.


Assuntos
Camada de Gelo/microbiologia , Pedobacter/classificação , Filogenia , Regiões Árticas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Dados de Sequência Molecular , Pedobacter/genética , Pedobacter/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Svalbard , Vitamina K 2/análogos & derivados , Vitamina K 2/química
16.
Int J Syst Evol Microbiol ; 64(Pt 11): 3798-3803, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25142212

RESUMO

A novel, Gram-stain-negative, aerobic, non-motile and rod-shaped bacterium, designated R9-86(T), was isolated from tundra soil collected near Ny-Ålesund, Svalbard Archipelago, Norway (78° N). Growth occurred at 4-28 °C (optimum, 22-25 °C) and at pH 6.0-9.0 (optimum, pH 7.0). Flexirubin-type pigments were absent. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain R9-86(T) belonged to the genus Terrimonas in the family Chitinophagaceae. 16S rRNA gene sequence similarities between strain R9-86(T) and the type strains of species of the genus Terrimonas with validly published names ranged from 93.7 to 95.0%. Strain R9-86(T) contained iso-C(15:1)-G (25.7%), iso-C(15:0) (24.5%), iso-C(17:0)-3OH (18.3%) and summed feature 3 (C(16:1)ω7c and/or C(16:1)ω6c, 8.7%) as its major cellular fatty acids; phosphatidylethanolamine and an unknown polar lipid as its main polar lipids, and MK-7 as its predominant respiratory quinone. The DNA G+C content was 48.4 mol%. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain R9-86(T) is considered to represent a novel species of the genus Terrimonas, for which the name Terrimonas arctica sp. nov. is proposed. The type strain is R9-86(T) ( =CCTCC AB 2011004(T) =NRRL B-59114(T)).


Assuntos
Bacteroidetes/classificação , Filogenia , Microbiologia do Solo , Tundra , Regiões Árticas , Técnicas de Tipagem Bacteriana , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Svalbard , Vitamina K 2/análogos & derivados , Vitamina K 2/química
17.
ACS Appl Mater Interfaces ; 16(3): 3809-3818, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38211320

RESUMO

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.

18.
RSC Adv ; 13(5): 3306-3316, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36756417

RESUMO

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.

19.
Quantum Front ; 2(1): 11, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37780230

RESUMO

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.

20.
J Agric Food Chem ; 71(49): 19622-19637, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38014964

RESUMO

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.


Assuntos
Microbioma Gastrointestinal , Ratos , Humanos , Animais , Eixo Encéfalo-Intestino , Animais Recém-Nascidos , Nucleotídeos , RNA Ribossômico 16S/genética , Leite Humano
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