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Frontiers in Microbiology 2021Commercial table salt is a condiment with food preservative properties by decreasing water activity and increasing osmotic pressure. Salt is also a source of halophilic...
Commercial table salt is a condiment with food preservative properties by decreasing water activity and increasing osmotic pressure. Salt is also a source of halophilic bacteria and archaea. In the present research, the diversity of halotolerant and halophilic microorganisms was studied in six commercial table salts by culture-dependent and culture-independent techniques. Three table salts were obtained from marine origins: Atlantic Ocean, Mediterranean (Ibiza Island), and Odiel marshes (supermarket marine salt). Other salts supplemented with mineral and nutritional ingredients were also used: Himalayan pink, Hawaiian black, and one with dried vegetables known as Viking salt. The results of 16S rRNA gene sequencing reveal that the salts from marine origins display a similar archaeal taxonomy, but with significant variations among genera. Archaeal taxa , , , , , , , and were prevalent in those three marine salts. Furthermore, the most abundant archaeal genera present in all salts were , , , , , , and uncultured . sp. was the most frequent bacteria, represented almost in all salts. Other genera such as , , and were the most frequent taxa in the Viking, Himalayan pink, and black salts, respectively. Interestingly, the genus was detected only in marine-originated salts. A collection of 76 halotolerant and halophilic bacterial and haloarchaeal species was set by culturing on different media with a broad range of salinity and nutrient composition. Comparing the results of 16S rRNA gene metataxonomic and culturomics revealed that culturable bacteria , , , , , , , , , , , , , and also Archaea , , and were identified at least in one sample by both methods. Our results show that salts from marine origins are dominated by Archaea, whereas salts from other sources or salt supplemented with ingredients are dominated by bacteria.
PubMed: 34777272
DOI: 10.3389/fmicb.2021.714110 -
Frontiers in Microbiology 2023Adverse abiotic environmental conditions including excess salt in the soil, constantly challenge plants and disrupt the function of plants, even inflict damage on...
INTRODUCTION
Adverse abiotic environmental conditions including excess salt in the soil, constantly challenge plants and disrupt the function of plants, even inflict damage on plants. Salt stress is one of the major limiting factors for agricultural productivity and severe restrictions on plant growth. One of the critical ways to improve plant salt tolerance is halotolerant bacteria application. However, few such halotolerant bacteria were known and should be explored furtherly.
METHODS
Halophilic bacterium strain was isolated from saline soil with serial dilution and identified with classical bacteriological tests and 16S rRNA analysis. Perennial ryegrass ( L) was used in this study to evaluate the potential effect of the bacteria.
RESULTS AND DISCUSSION
A halophilic bacterium strain GDHT17, was isolated from saline soil, which grows in the salinities media with 1.0%, 5.0%, and 10.0% (w/v) NaCl, and identified as . Inoculating GDHT17 can significantly promote ryegrass's seedling height and stem diameter and increase the root length, diameter, and surface area at different salt concentrations, indicating the significant salt stress alleviating effect of GDHT17 on the growth of ryegrass. The alleviating effect on roots growth showed more effective, especially on the root length, which increased significantly by 26.39%, 42.59%, and 98.73% at salt stress of 100 mM, 200 mM, and 300 mM NaCl when the seedlings were inoculated with GDHT17. Inoculating GDHT17 also increases perennial ryegrass biomass, water content, chlorophyll and carotenoid content under salt stress. The contents of proline and malonaldehyde in the seedlings inoculated with GDHT17 increased by 83.50% and 6.87%, when treated with 300 mM NaCl; however, the contents of MDA and Pro did not show an apparent effect under salt stress of 100 mM or 200 mM NaCl. GDHT17-inoculating maintained the Na/K ratio in the salt-stressed ryegrass. The Na/K ratio decreased by 26.52%, 6.89%, and 29.92% in the GDHT17-inoculated seedling roots treated with 100 mM, 200 mM, and 300 mM NaCl, respectively. The GDHT17-inoculating increased the POD and SOD activity of ryegrass seedlings by 25.83% and 250.79%, respectively, at a salt stress of 300 mM NaCl, indicating the properties of GDHT17, improving the activity of antioxidant enzymes of ryegrass at the salt-stress condition. Our results suggest that GDHT17 may alleviate salt stress on ryegrass in multiple ways; hence it can be processed into microbial inoculants to increase salt tolerance of ryegrass, as well as other plants in saline soil.
PubMed: 37564282
DOI: 10.3389/fmicb.2023.1213884 -
Iranian Journal of Microbiology Jun 2021Halothermophilic bacteria are adapted to high osmolarity and can grow in high saline environments and high temperatures. This study was aimed at the isolation of...
BACKGROUND AND OBJECTIVES
Halothermophilic bacteria are adapted to high osmolarity and can grow in high saline environments and high temperatures. This study was aimed at the isolation of halothermophilic bacteria from Howz-e Sultan hypersaline lake in the central desert zone in Iran.
MATERIALS AND METHODS
Samples were collected and after preparing dilutions, the samples were cultured on Molten haloid agar with different salt concentrations (5-35%), then the plates were incubated at 35-70ºC in both aerobic and anaerobic conditions. Biochemical characterizations, utilization of carbon sources, production of exoenzymes and antibiotic susceptibility were investigated. Taxonomic and phylogenetic analyses were performed using 16S rRNA gene sequences.
RESULTS
One of the isolated bacteria was found to be Gram-positive, hyperhalophilic, thermophilic, endospore-forming, and was named as 1-9 h isolate. The bacterial cells were bacilli-shaped, which produced endospores at a subterminal position. This isolate was an aerobe and facultative anaerobe and grew between pH 5.0 and 10.0 (optimal growth at pH 7.0-7.5), at temperature between 15°C and 65°C (optimal growth at 40-45°C) and at salinity of 9-32% (w/v) NaCl, growing optimally at 18% (w/v) NaCl. On the basis of 16S rRNA gene sequence analysis, isolate 1-9 h belongs to the genus within the phylum Firmicutes and showed the closest phylogenetic similarity to sp. IBP-V003 (99.0%).
CONCLUSION
Based on the results of its phenotypic and genotypic properties, strain 1-9 h represents a novel strain of the genus It can be used in various fields of industry and biotechnology.
PubMed: 34540179
DOI: 10.18502/ijm.v13i3.6403 -
Frontiers in Nutrition 2022Insects are a potential alternative protein source to solve the food shortage crisis. Previous studies have illustrated that probiotics can improve the substrate...
Insects are a potential alternative protein source to solve the food shortage crisis. Previous studies have illustrated that probiotics can improve the substrate conversion efficiency of insects and increase insect protein content. However, the effects of probiotics on insect physiology and nutrient metabolism are still not well understood. Here, the black soldier fly larvae (BSFL), (Diptera: Stratiomyidae), was used as a study subject to deeply investigate the specific interaction among a novel probiotic, EEAM 10B (10B), intestinal microbiota, and the host. In this study, the effects of 10B on the survival and physiology of BSFL were first analyzed. It shows that 10B significantly elevated the substrate conversion rate, average dry weight, and protein content of BSFL by 5%, 0.13 g/pc, and 8%, respectively. Then, we assessed the effect of 10B on the microbial community composition in the gut and frass of BSFL using Illumina Miseq sequencing. It shows that 10B significantly altered the microbial composition of the gut, but not that of the frass. Pearson's correlation analysis further showed that the , , and were positively correlated with the survival rate, crude protein content, and substrate conversion rate of BSFL. To further investigate the effect of 10B on host metabolism, metabolic analyses on germ-free BSFL, monobacterial intestinal BSFL, and natural BSFL were also performed. The results proved that 10B (i) played a vital role in the survival of BSFL; and (ii) regulated the amino acid synthetic and metabolic process of BSFL, thus leading to the rise of the protein content of BSFL. In addition, vitamin backfill assays verified that the BSFL survival rate was significantly improved by supplying the germ-free BSFL with riboflavin, which further suggests that 10B determines the survival of BSFL delivering riboflavin. Overall, this study provides a reference for understanding the comprehensive contribution of a specific probiotic to its host.
PubMed: 35662952
DOI: 10.3389/fnut.2022.880488 -
Journal of Translational Medicine Jan 2024Various clinical similarities are present in ischemic (ICM) and idiopathic dilated cardiomyopathy (IDCM), leading to ambiguity on some occasions. Previous studies have...
BACKGROUND
Various clinical similarities are present in ischemic (ICM) and idiopathic dilated cardiomyopathy (IDCM), leading to ambiguity on some occasions. Previous studies have reported that intestinal microbiota appeared dysbiosis in ICM, whether implicating in the IDCM remains unclear. The aim of this study was to assess the alterations in intestinal microbiota and fecal metabolites in ICM and IDCM.
METHODS
ICM (n = 20), IDCM (n = 22), and healthy controls (HC, n = 20) were enrolled in this study. Stool samples were collected for 16S rRNA gene sequencing and gas chromatography-mass spectrometry (GC-MS) analysis.
RESULTS
Both ICM and IDCM exhibited reduced alpha diversity and altered microbial community structure compared to HC. At the genus level, nine taxa including Blautia, [Ruminococcus]_torques_group, Christensenellaceae_R-7_group, UCG-002, Corynebacterium, Oceanobacillus, Gracilibacillus, Klebsiella and Citrobacter was specific to ICM, whereas one taxa Alistipes uniquely altered in IDCM. Likewise, these changes were accompanied by significant metabolic differences. Further differential analysis displayed that 18 and 14 specific metabolites uniquely changed in ICM and IDCM, respectively. The heatmap was generated to display the association between genera and metabolites. Receiver operating characteristic curve (ROC) analysis confirmed the predictive value of the distinct microbial-metabolite features in disease status. The results showed that microbial (area under curve, AUC = 0.95) and metabolic signatures (AUC = 0.84) were effective in discriminating ICM from HC. Based on the specific microbial and metabolic features, the patients with IDCM could be separated from HC with an AUC of 0.80 and 0.87, respectively. Furthermore, the gut microbial genus (AUC = 0.88) and metabolite model (AUC = 0.89) were comparable in predicting IDCM from ICM. Especially, the combination of fecal microbial-metabolic features improved the ability to differentiate IDCM from ICM with an AUC of 0.96.
CONCLUSION
Our findings highlighted the alterations of gut microbiota and metabolites in different types of cardiomyopathies, providing insights into the pathophysiological mechanisms of myocardial diseases. Moreover, multi-omics analysis of fecal samples holds promise as a non-invasive tool for distinguishing disease status.
Topics: Humans; Cardiomyopathy, Dilated; Gastrointestinal Microbiome; RNA, Ribosomal, 16S; Metabolome; Dysbiosis
PubMed: 38254195
DOI: 10.1186/s12967-023-04605-6 -
MicrobiologyOpen Feb 2019Microbial culturomics represents an ongoing revolution in the characterization of the human gut microbiota. By using three culture media containing high salt...
Microbial culturomics represents an ongoing revolution in the characterization of the human gut microbiota. By using three culture media containing high salt concentrations (10, 15, and 20% [w/v] NaCl), we attempted an exhaustive exploration of the halophilic microbial diversity of the human gut and isolated strain Marseille-P2481 (= CSUR P2481 = DSM 103076), a new moderately halophilic bacterium. This bacterium is a Gram-positive, strictly aerobic, spore-forming rod that is motile by use of a flagellum and exhibits catalase, but not oxidase activity. Strain Marseille-P2481 was cultivated in media containing up to 20% (w/v) NaCl, with optimal growth being obtained at 37°C, pH 7.0-8.0, and 7.5% [w/v] NaCl). The major fatty acids were 12-methyl-tetradecanoic acid and hexadecanoic acid. Its draft genome is 4,548,390 bp long, composed of 11 scaffolds, with a G+C content of 39.8%. It contains 4,335 predicted genes (4,266 protein coding including 89 pseudogenes and 69 RNA genes). Strain Marseille-P2481 showed 96.57% 16S rRNA sequence similarity with Gracilibacillus alcaliphilus strain SG103 , the phylogenetically closest species with standing in nomenclature. On the basis of its specific features, strain Marseille-P2481 was classified as type strain of a new species within the genus Gracilibacillus for which the name Gracilibacillus timonensis sp. nov. is formally proposed.
Topics: Aerobiosis; Bacillaceae; Base Composition; Child; Cluster Analysis; Computational Biology; Cytosol; DNA, Bacterial; DNA, Ribosomal; Fatty Acids; Gastrointestinal Microbiome; Genome, Bacterial; Healthy Volunteers; Humans; Hydrogen-Ion Concentration; Locomotion; Male; Phylogeny; RNA, Ribosomal, 16S; Senegal; Sequence Analysis, DNA; Sodium Chloride; Temperature
PubMed: 29675845
DOI: 10.1002/mbo3.638 -
Is there still room to explore cyclodextrin glycosyltransferase-producers in Brazilian biodiversity?Anais Da Academia Brasileira de Ciencias 2018In the present work, different Brazilian biomes aiming to identify and select cyclodextrin glycosyltransferase-producer bacteria are explored. This enzyme is responsible...
In the present work, different Brazilian biomes aiming to identify and select cyclodextrin glycosyltransferase-producer bacteria are explored. This enzyme is responsible for converting starch to cyclodextrin, which are interesting molecules to carry other substances of economic interest applied by textile, pharmaceutical, food, and other industries. Based on the enzymatic index, 12 bacteria were selected and evaluated, considering their capacity to produce the enzyme in culture media containing different starch sources. It was observed that the highest yields were presented by the bacteria when grown in cornstarch. These bacteria were also characterized by sequencing of the 16S rRNA region and were classified as Bacillus, Paenibacillus, Gracilibacillus and Solibacillus.
Topics: Biodiversity; Bioprospecting; Brazil; Culture Media; Glucosyltransferases; Gram-Positive Bacteria; Hydrogen-Ion Concentration; RNA, Ribosomal, 16S; Starch
PubMed: 29898106
DOI: 10.1590/0001-3765201820170670 -
PloS One 2020Halophiles are relatively unexplored as potential sources of novel species. However, little is known about the culturable bacterial diversity thrive in hypersaline...
Halophiles are relatively unexplored as potential sources of novel species. However, little is known about the culturable bacterial diversity thrive in hypersaline lakes. In this work, a total of 343 bacteria from sediment samples of Aiding Lake, China, were isolated using nine different media supplemented with 5% or 15% (w/v) NaCl. The number of species and genera of bacteria recovered from the different media varied, indicating the need to optimize the isolation conditions. The results showed an unexpected level of bacterial diversity, with four phyla (Actinobacteria, Firmicutes, Proteobacteria, and Rhodothermaeota), fourteen orders (Actinopolysporales, Alteromonadales, Bacillales, Balneolales, Chromatiales, Glycomycetales, Jiangellales, Micrococcales, Micromonosporales, Oceanospirillales, Pseudonocardiales, Rhizobiales, Streptomycetales, and Streptosporangiales), including 17 families, 43 genera (including two novel genera), and 71 species (including four novel species). The predominant phyla included Actinobacteria and Firmicutes and the predominant genera included Actinopolyspora, Gracilibacillus, Halomonas, Nocardiopsis, and Streptomyces. To our knowledge, this is the first time that members of phylum Rhodothermaeota were identified in sediment samples from a salt lake.
Topics: Bacteria; Biodiversity; China; Geologic Sediments; Lakes; Phylogeny; RNA, Ribosomal, 16S; Sodium Chloride
PubMed: 32649724
DOI: 10.1371/journal.pone.0236006 -
New Microbes and New Infections Nov 2020Using the taxonogenomics method, we describe strain Marseille-P3801, a new species previously isolated from a salty stool of a 20-year-old man from N'Diop, Senegal. It...
Using the taxonogenomics method, we describe strain Marseille-P3801, a new species previously isolated from a salty stool of a 20-year-old man from N'Diop, Senegal. It is a Gram-positive, aerobic and motile bacillus. The major fatty acids are C (59%), C (16%) and C (11%). Strain Marseille-P3801 exhibits a 98.45% sequence similarity with strain TP2-8, the phylogenetically closest species. Its genome is 4.66 Mb with 39.6 mol% G + C content.
PubMed: 33294194
DOI: 10.1016/j.nmni.2020.100799 -
New Microbes and New Infections Nov 2017We report the isolation of three bacterial strains that could not be identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry...
We report the isolation of three bacterial strains that could not be identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry screening. '' sp. nov., '' sp. nov. and '' sp. nov. are halophilic species isolated from salty human stools by culturomics.
PubMed: 29062488
DOI: 10.1016/j.nmni.2017.08.006