Changes in Microbial Diversity, Physicochemical Characteristics, and Flavor Substances During Maotai-Flavored Liquor Fermentation and Their Correlations

Abstract BackgroundRhizosphere microbes possess important effects on plant growth and quality. Here we collected tobacco roots and leaf samples from ten places in Yunnan province to investigate the interaction of the rhizosphere microbes, the soil physicochemical characteristics, and the tobacco leaf properties. ResultsA high-throughput sequencing method was used to sequence the V3–V4 region of 16S rRNA genes, and the operational taxonomic units (OTUs) were clustered using QIIME under 97% identity. A total of 4571 OTUs were obtained from the 30 tobacco root samples, and the top three phyla were Proteobacteria, Acidobacteria, and Actinobacteria, while the top three annotated genera were Gp6, Gemmatimonas, and Gp4. Redundancy analysis (RDA) showed that most of the soil physicochemical properties (10 out of 17) had a significant influence on the rhizosphere microbial community. Both correlation analysis and RDA analysis revealed that quick potassium (K) and Acidobacteria_Gp3 had a significant correlation with the tobacco leaf properties. The variance partitioning analysis showed that rhizosphere microbes had a bigger influence on the tobacco leaf properties. ConclusionsOur results showed great differences in the rhizosphere microbial diversity of tobacco and complex interaction among the microbial diversity, soil physicochemical characteristics, and tobacco leaf properties.

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Microbial diversity and physicochemical characteristics of tropical karst soils in the northeastern Yucatan peninsula, Mexico

Applied Soil Ecology ◽

10.1016/j.apsoil.2021.103969 ◽

2021 ◽

Vol 165 ◽

pp. 103969

Author(s):

Jazmín Santillán ◽

Rafael López-Martínez ◽

Eduardo J. Aguilar-Rangel ◽

Karina Hernández-García ◽

María Soledad Vásquez-Murrieta ◽

...

Keyword(s):

Microbial Diversity ◽

Yucatan Peninsula ◽

Physicochemical Characteristics ◽

Yucatán Peninsula ◽

Karst Soils ◽

Tropical Karst

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Applications of SEM/EDXA in cement clinker investigation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100177489 ◽

1990 ◽

Vol 48 (4) ◽

pp. 870-871

Author(s):

Arezki Tagnit-Hamou ◽

Shondeep L. Sarkar

Keyword(s):

Mineralogical Composition ◽

Physicochemical Characteristics ◽

Cement Clinker ◽

Accurate Information ◽

Phase Identification ◽

History Of ◽

Bulk Chemical ◽

Resolution Imaging ◽

Proven Method ◽

Instantaneous Chemical

All the desired properties of cement primarily depend on the physicochemical characteristics of clinker from which the cement is produced. The mineralogical composition of the clinker forms the most important parameter influencing these properties.Optical microscopy provides reasonably accurate information pertaining to the thermal history of the clinker, while XRDA still remains the proven method of phase identification, and bulk chemical composition of the clinker can be readily obtained from XRFA. Nevertheless, all these microanalytical techniques are somewhat limited in their applications, and SEM/EDXA combination fills this gap uniquely by virtue of its high resolution imaging capability and possibility of instantaneous chemical analysis of individual phases.Inhomogeneities and impurities in the raw meal, influence of kiln conditions such as sintering and cooling rate being directly related to the microstructure can be effectively determined by SEM/EDXA. In addition, several physical characteristics of cement, such as rhcology, grindability and hydraulicity also depend on the clinker microstructure.

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Common modifications of selenocysteine in selenoproteins

Essays in Biochemistry ◽

10.1042/ebc20190051 ◽

2019 ◽

Vol 64 (1) ◽

pp. 45-53 ◽

Cited By ~ 1

Author(s):

Elias S.J. Arnér

Keyword(s):

Amino Acids ◽

Covalent Binding ◽

Physicochemical Characteristics ◽

Redox Active

Abstract Selenocysteine (Sec), the sulfur-to-selenium substituted variant of cysteine (Cys), is the defining entity of selenoproteins. These are naturally expressed in many diverse organisms and constitute a unique class of proteins. As a result of the physicochemical characteristics of selenium when compared with sulfur, Sec is typically more reactive than Cys while participating in similar reactions, and there are also some qualitative differences in the reactivities between the two amino acids. This minireview discusses the types of modifications of Sec in selenoproteins that have thus far been experimentally validated. These modifications include direct covalent binding through the Se atom of Sec to other chalcogen atoms (S, O and Se) as present in redox active molecular motifs, derivatization of Sec via the direct covalent binding to non-chalcogen elements (Ni, Mb, N, Au and C), and the loss of Se from Sec resulting in formation of dehydroalanine. To understand the nature of these Sec modifications is crucial for an understanding of selenoprotein reactivities in biological, physiological and pathophysiological contexts.

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