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Frontiers in Physiology 2024There are various categorization models of high-intensity interval training (HIIT) in the literature that need to be more consistent in definition, terminology, and... (Review)
Review
There are various categorization models of high-intensity interval training (HIIT) in the literature that need to be more consistent in definition, terminology, and concept completeness. In this review, we present a training goal-oriented categorization model of HIIT, aiming to find the best possible consensus among the various defined types of HIIT. This categorization concludes with six different types of HIIT derived from the literature, based on the interaction of interval duration, interval intensity and interval:recovery ratio. We discuss the science behind the defined types of HIIT and shed light on the possible effects of the various types of HIIT on aerobic, anaerobic, and neuromuscular systems and possible transfer effects into competition performance. We highlight various research gaps, discrepancies in findings and not yet proved know-how based on a lack of randomized controlled training studies, especially in well-trained to elite athlete cohorts. Our HIIT "toolbox" approach is designed to guide goal-oriented training. It is intended to lay the groundwork for future systematic reviews and serves as foundation for meta-analyses.
PubMed: 38957216
DOI: 10.3389/fphys.2024.1414307 -
Biotechnology and Bioengineering Jul 2024Acetogenic Clostridia are obligate anaerobes that have emerged as promising microbes for the renewable production of biochemicals owing to their ability to efficiently...
Acetogenic Clostridia are obligate anaerobes that have emerged as promising microbes for the renewable production of biochemicals owing to their ability to efficiently metabolize sustainable single-carbon feedstocks. Additionally, Clostridia are increasingly recognized for their biosynthetic potential, with recent discoveries of diverse secondary metabolites ranging from antibiotics to pigments to modulators of the human gut microbiota. Lack of efficient methods for genomic integration and expression of large heterologous DNA constructs remains a major challenge in studying biosynthesis in Clostridia and using them for metabolic engineering applications. To overcome this problem, we harnessed chassis-independent recombinase-assisted genome engineering (CRAGE) to develop a workflow for facile integration of large gene clusters (>10 kb) into the human gut acetogen Eubacterium limosum. We then integrated a non-ribosomal peptide synthetase gene cluster from the gut anaerobe Clostridium leptum, which previously produced no detectable product in traditional heterologous hosts. Chromosomal expression in E. limosum without further optimization led to production of phevalin at 2.4 mg/L. These results further expand the molecular toolkit for a highly tractable member of the Clostridia, paving the way for sophisticated pathway engineering efforts, and highlighting the potential of E. limosum as a Clostridial chassis for exploration of anaerobic natural product biosynthesis.
PubMed: 38956879
DOI: 10.1002/bit.28796 -
Cell Death & Disease Jul 2024
PubMed: 38956061
DOI: 10.1038/s41419-024-06613-w -
Current Microbiology Jul 2024Turkey litter waste is lignocellulosic and keratinous, requiring prior enzymatic treatment to facilitate fiber hydrolysis and utilization by microorganisms in anaerobic...
Turkey litter waste is lignocellulosic and keratinous, requiring prior enzymatic treatment to facilitate fiber hydrolysis and utilization by microorganisms in anaerobic digestion (AD) process. The understanding of the performance of microorganisms in AD can be facilitated through molecular biology and bioinformatics tools. This study aimed to determine the taxonomic profile and functional prediction of microbial communities in the AD of turkey litter waste subjected to enzymatic pretreatment and correlate it with operational parameters. The tests involved the use of turkey litter (T) at 25 g L of volatile solids, a granular inoculum (S) (10% m/v), and the addition of cellulase (C), and pectinase (P) enzymes at four concentrations. The use of enzymes increased methane production by 19% (turkey litter, inoculum, and cellulase-TSC4) and 15% (turkey litter, inoculum, and enzymatic pectinase-TSP4) compared to the control (turkey litter and inoculum-TS), being more effective in TSC4 (667.52 mLCH), where there was consumption of acetic, butyric, and propionic acids. The pectinase assay (TSP4) showed a methane production of 648 mLCH and there was the accumulation of metabolites. Cellulolytic microorganisms Bacteroides, Ruminofilibacter, Lachnospiraceae, Ruminococcaceae, and Methanosaeta were favored in TSC4. In TSP4, the predominant genus was Macellibacteroides and Methanosarcina, and genes involved in methylotrophic methanogenesis were also found (mtaB, mtmB, and mtbB). Enzymes involved in hydrogenotrophic methanogenesis were identified in both assays (TSC4 and TSP4). Molecular tools helped to understand the metabolic routes involved in AD with enzymatic treatment, allowing the elaboration of strategies to improve the sustainable degradation of turkey litter waste.
Topics: Anaerobiosis; Animals; Methane; Cellulase; Bacteria; Turkeys; Polygalacturonase; Hydrolysis; Lignin; Agriculture; Metagenomics
PubMed: 38955830
DOI: 10.1007/s00284-024-03787-6 -
Marine Pollution Bulletin Jul 2024Metal materials undergo severe corrosion in eutrophic environments. The effect of DO decay stimulated by high concentrations of nitrogen and phosphorus pollutants on... (Review)
Review
Metal materials undergo severe corrosion in eutrophic environments. The effect of DO decay stimulated by high concentrations of nitrogen and phosphorus pollutants on microorganisms leads to the coupling of electrochemical and microbial corrosion processes. However, there are few studies on microbial corrosion mechanisms in eutrophic environments. This article discusses the corrosive factors of marine eutrophication, summarizes the impact of marine eutrophication on microbial corrosion and the potential mechanisms, including aerobic biofilm corrosion, aerobic & anaerobic mixed biofilm corrosion, and anaerobic microbial electron transfer corrosion, and expounds on the research methods for microbial corrosion of materials serving in estuarine areas prone to pollution. Microbial prevention and control, such as nutrient restriction and microbial interspecies competition, are of research value in the field of green protection. Microbial corrosion mechanisms studies in marine eutrophication environments are significant for environment monitor development, water intake and algae control technologies, and corrosion protection in polluted environments.
PubMed: 38955090
DOI: 10.1016/j.marpolbul.2024.116637 -
Journal of Hazardous Materials Jun 2024Ball-milled plastic char supported nano zero-valent iron (nZVI@BMPC) and their application combined with anaerobic sludge for microbial dechlorination of...
Ball-milled plastic char supported nano zero-valent iron (nZVI@BMPC) and their application combined with anaerobic sludge for microbial dechlorination of 2,4,6-trichlorophenol (2,4,6-TCP) were investigated. The XRD and FTIR analysis proved composition of zero valent states of iron, and the BET and SEM analysis showed that nZVI was uniformly distributed on the surface of BMPC. Successive addition of 1000 mg/L sodium lactate and nZVI@BMPC enhanced the acclamation of anaerobic sludge and resulted in the degradation of 4-CP within 80 days. The acclimated consortium with nZVI@BMPC completely degraded 2,4,6-TCP into CH and CO, and the key dechlorination route was through 4-CP dechlorinaion and mineralization. The degradation rate of 2,4,6-TCP with nZVI@BMPC was 0.22/d, greater than that without nZVI@BMPC. The dechlorination efficiency was enhanced in the Fe/Fe system controlled by nZVI@BMPC and iron-reducing bacteria. Metagenomic analysis result showed that the dominant de-chlorinators were Chloroflexi sp., Desulfovibrio, and Pseudomonas, which could directly degrade 2,4,6-TCP to 4-CP, especially, Chloroflexi bacterium could concurrently be used to mineralize 4-CP. The relative abundance of the functional genes cprA, acoA, acoB, and tfdB increased significantly in the presence of the nZVI@BMPC. This study provides a new strategy can be a good alternative for possible application in groundwater remediation.
PubMed: 38954853
DOI: 10.1016/j.jhazmat.2024.135063 -
International Journal of Systematic and... Jul 2024Four rod-shaped, non-motile, non-spore-forming, facultative anaerobic, Gram-stain-positive lactic acid bacteria, designated as EB0058, SCR0080, LD0937 and SCR0063, were...
Four rod-shaped, non-motile, non-spore-forming, facultative anaerobic, Gram-stain-positive lactic acid bacteria, designated as EB0058, SCR0080, LD0937 and SCR0063, were isolated from different corn and grass silage samples. The isolated strains were characterized using a polyphasic approach and EB0058 and SCR0080 were identified as by 16S rRNA gene sequence analysis. Based on whole-genome sequence-based characterization, EB0058 and SCR0080 were separated into a distinct clade from DSM 20178, together with CECT9104 and UD2202, whose genomic sequences are available from NCBI GenBank. The average nucleotide identity (ANI) values within the new subgroup are 99.9 % and the digital DNA-DNA hybridization (dDDH) values are 99.3-99.9 %, respectively. In contrast, comparison of the new subgroup with publicly available genomic sequences of strains, including the type strain DSM 20178, revealed dDDH values of 70.2-72.5 % and ANI values of 96.2-96.6 %. Based on their chemotaxonomic, phenotypic and phylogenetic characteristics, EB0058 and SCR0080 represent a new subspecies of . The name subsp. subsp. nov. is proposed with the type strain EB0058 (=DSM 116376=NCIMB 15474). According to the results of 16S rRNA gene sequencing, LD0937 and SCR0063 are members of the group. The dDDH value between the isolates LD0937 and SCR0063 was 67.6 %, which is below the species threshold of 70 %, clearly showing that these two isolates belong to different species. For both strains, whole genome-sequencing revealed that the closest relatives within the group were DSM 11542 (dDDH 66.5 and 65.9 %) and DSM 20011 (dDDH 64.1 and 64.9 %). Based on the genomic, chemotaxonomic and morphological data obtained in this study, two novel species, sp. nov. and sp. nov. are proposed and the type strains are LD0937 (=DSM 116105=NCIMB 15471) and SCR0063 (=DSM 116297=NCIMB 15473), respectively.
Topics: RNA, Ribosomal, 16S; Phylogeny; Bacterial Typing Techniques; Zea mays; Silage; DNA, Bacterial; Nucleic Acid Hybridization; Sequence Analysis, DNA; Fatty Acids; Poaceae; Base Composition; Whole Genome Sequencing; Lacticaseibacillus
PubMed: 38954457
DOI: 10.1099/ijsem.0.006441 -
Biodegradation Jul 2024Evaluating industrial wastes in the system with minimum preprocessing and generation economically valuable products from them have critical importance. In this regard,...
Evaluating industrial wastes in the system with minimum preprocessing and generation economically valuable products from them have critical importance. In this regard, especially cheap, wieldy, and readily available catalysts have been researched to increase variety of useful products in pyrolysis systems, to reduce process time, and to increase quality and diversity of products. Therefore, in this study, marble sludge (named K1) was evaluated as catalyst at different dosages (10%, 20%, 30%, 50%) and pyrolysis temperatures (300, 500, 700 °C) in olive pomace (OP) pyrolysis and; the potential green applications of produced new biochars at new usage areas with different purposes based on characteristics were investigated. ANOVA test results showed that temperature and catalysts ratio had significant effect on pyrolysis product yields since significance value for K1 and temperature was lower than 0.05 for pyrolysis products. OP-K1 biochars had alkaline properties and high earth metal quantities. Moreover, increment in K1 ratio and temperature resulted in decrement of the biochar surface acidity. Therefore, it can be indicated that these biochars can have a potential usage for anaerobic digestion processes, lithium-ion batteries, and direct carbon solid oxide fuel cell (DC-SOFC) but further electrochemical property test should be performed. Moreover, produced biochars can be alternative fuels in some processes instead of coal since they have low S content and high heat values. Consequently, it is foreseen that produced biochars will have an important place in the development of potential usage areas with a new and environmentally friendly approach in different areas apart from the conventional uses of catalytic pyrolysis chars.
PubMed: 38954367
DOI: 10.1007/s10532-024-10088-z -
Folia Microbiologica Jul 2024Oral microorganisms are closely related to oral health, the occurrence of some oral diseases is associated with changes in the oral microbiota, and many studies have...
Oral microorganisms are closely related to oral health, the occurrence of some oral diseases is associated with changes in the oral microbiota, and many studies have demonstrated that traditional smoking can affect the oral microbial community. However, due to the short time since the emergence of e-cigarettes, fewer studies are comparing oral microorganisms for users of e-cigarettes versus cigarettes. We collected saliva from 40 non-smokers (NS), 46 traditional cigarette smokers (TS), and 27 e-cigarette consumers (EC), aged between 18 and 35 years. We performed 16S rRNA gene sequencing on the saliva samples collected to study the effects of e-cigarettes versus traditional cigarettes on the oral microbiome. The results showed that compared with the NS group, the alpha diversity of oral flora in saliva was altered in the TS group, with no significant change in the e-cigarette group. Compared with the NS and EC groups, the relative abundance of Actinomyces and Prevotella was increased in the TS group. However, compared with the NS and TS groups, the relative abundance of Veillonella was increased, and the relative abundance of Porphyromonas and Peptostreptococcus was decreased in the EC group. These results showed that both e-cigarettes and traditional cigarettes could alter the structure and composition of oral microbiota. The use of traditional cigarettes promotes the growth of some anaerobic bacteria, which may contribute to dental decay and bad breath over time. E-cigarettes have a different effect on the structure and composition of the oral microbial community compared to conventional cigarettes. In order to better understand the effects of e-cigarettes and traditional cigarettes on users' mouths, future studies will investigate the relationship between diseases such as dental caries and periodontitis and changes in oral microbial species levels.
PubMed: 38954243
DOI: 10.1007/s12223-024-01185-w -
Current Microbiology Jul 2024Two Gram-stain-negative, facultative anaerobic, rod-shaped, motile bacterial strains, designated F26243 and F60267 were isolated from coastal sediment in Weihai, China....
Two Gram-stain-negative, facultative anaerobic, rod-shaped, motile bacterial strains, designated F26243 and F60267 were isolated from coastal sediment in Weihai, China. Strains F26243 and F60267 were grown at 4-40 °C (optimum 33 °C), pH 7.0-9.5 and pH 6.5-9.5 (optimum at pH 7.0), in the presence of 1.0-7.0% (w/v) NaCl (optimum 2.5%) and 1.0-12.0% (w/v) NaCl (optimum 2.0%), respectively. The 16S rRNA gene sequences phylogenetic analysis showed that strains F26243 and F60267 are closely related to the genus Marinobacter and exhibited the highest sequence similarities to Marinobacter salexigens HJR7 (97.7% and 98.0%, respectively), the similarity between two isolates was 96.7%. Strains F26243 and F60267 displayed genomic DNA G + C content of 53.6% and 53.8%, respectively. When compared to the M. salexigens HJR7, the average nucleotide identity (ANI) values were 83.7% and 84.1%, and the percentage of conserved proteins (POCP) values were 79.9% and 84.6%, respectively. Ubiquinone 9 (Q-9) was the only respiratory quinone detected in both isolates. The major cellular fatty acids (> 10.0%) were summed feature 3 (comprising Cω7c and/or Cω6c), C and Cω9c. The polar lipid profiles of strains F26243 and F60267 contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidyldimethylethanolamine, phosphatidylglycerol, aminophospholipid and one unidentified phospholipid. Based on genomic characteristics, phenotypic and chemotaxonomic, strains F26243 and F60267 represent two novel species of the genus Marinobacter, for which the names Marinobacter sediminicola sp. nov. and Marinobacter xiaoshiensis sp. nov. are proposed, the type strains are F26243 (= KCTC 92640 = MCCC 1H01345) and F60267 (= KCTC 92638 = MCCC 1H01346).
Topics: Marinobacter; Geologic Sediments; Phylogeny; RNA, Ribosomal, 16S; Base Composition; Fatty Acids; DNA, Bacterial; China; Bacterial Typing Techniques; Phospholipids; Sequence Analysis, DNA; Seawater
PubMed: 38954028
DOI: 10.1007/s00284-024-03782-x