Search

Highlights Panax notoginseng saponins could be biotransformed to generate five main metabolites, including GF1, GRh2, GC-K, PPT and PPD, by human gut microbiota. Gut microbiota profiles were significantly different in high protein, high fat and low fat, plant fiber-rich diet-pattern groups. Correlation analysis revealed potential relationships between metabolites and gut microbial species. Bifidobacterium adolescentis and Lactobacillus rhamnosus were selected as a representative species to metabolize PNS for the concerned metabolites.

Background: Panax notoginseng saponins (PNS) as the main effective substances from P. notoginseng with low bioavailability could be bio-converted by human gut microbiota. In our previous study, PNS metabolic variations mediated by gut microbiota have been observed between high fat, high protein (HF-HP) and low fat, plant fiber-rich (LF-PF) dietary subjects. In this study, we aimed to correspondingly characterize the relationship between distinct gut microbial species and PNS metabolites. Methods: Gut microbiota were collected from HF-HP and LF-PF dietary healthy adults and profiled by 16S rRNA gene sequencing. PNS were incubated with gut microbiota in vitro. A LC–MS/MS method was developed to quantify the five main metabolites yields including ginsenoside F1 (GF1), ginsenoside Rh2 (GRh2), ginsenoside compound K (GC-K), protopanaxatriol (PPT) and protopanaxadiol (PPD). The selected microbial species, Bifidobacterium adolescentis and Lactobacillus rhamnosus, were employed to metabolize PNS for the corresponding metabolites. Results: The five main metabolites were significantly different between the two diet groups. Compared with HF-HP group, the microbial genus Blautia, Bifidobacterium, Clostridium, Corynebacterium, Dorea, Enhydrobacter, Lactobacillus, Roseburia, Ruminococcus, SMB53, Streptococcus, Treponema and Weissella were enriched in LF-PF group, while Phascolarctobacterium and Oscillospira were relatively decreased. Furthermore, Spearman's correlative analysis revealed gut microbials enriched in LF-PF and HF-HP groups were positively and negatively associated with the five metabolites, respectively. Conclusions: Our data showed gut microbiota diversity led to the personalized bioconversion of PNS. Highlights: Panax notoginseng saponins could be biotransformed to generate five main metabolites, including GF1, GRh2, GC-K, PPT and PPD, by human gut microbiota. Gut microbiota profiles were significantly different in high protein, high fat and low fat, plant fiber-rich diet-pattern groups. Correlation analysis revealed potential relationships between metabolites and gut microbial species. Bifidobacterium adolescentis and Lactobacillus rhamnosus were selected as a representative species to metabolize PNS for the concerned metabolites. [ABSTRACT FROM AUTHOR]

• End-stage renal disease has a set of metabolic variation. • End-stage renal disease and clinical outcomes of peritoneal dialysis-related potential metabolic biomarkers were revealed. • The abundance of potential metabolic biomarkers was assessed in the validation cohort using multiple reaction monitoring based targeted metabolite analysis. • A 3-metabolite fingerprint classifier including isoleucine, cholic acid and adenine was included in a nomogram using the LASSO Cox regression model. • The 3-metabolite fingerprint classifier may be able to predict the clinical outcomes of peritoneal dialysis. Peritoneal dialysis (PD) helps prevent lethal complications of end-stage renal disease (ESRD). However, the clinical outcomes are affected by PD-related complications. We investigated metabolic biomarkers to estimate the clinical outcomes of PD and identify patients at high risk of downstream complications and recurrent/relapsing infections. Metabolites of normal control and ESRD patient were compared via an untargeted metabolomic analysis. Potential metabolic biomarkers were selected and quantified using a multiple reaction monitoring-based target metabolite detection method. A nomogram was built to predict the clinical outcomes of PD patients using clinical features and potential metabolic biomarkers with the least absolute shrinkage and selection operator Cox regression model. Twenty-five endogenous metabolites were identified and analyzed. ESRD-poor clinical outcome-related metabolic modules were constructed. Adenine, isoleucine, tyramine, xanthosine, phenylacetyl-L-glutamine, and cholic acid were investigated using the weighted gene correlation network analysis blue module. Potential metabolic biomarkers were differentially expressed between the NC and ESRD groups and the poor and good clinical outcomes of PD groups. A 3-metabolite fingerprint classifier of isoleucine, cholic acid, and adenine was included in a nomogram predicting the clinical outcomes of PD. Metabolic variations can predict the clinical outcomes of PD in ESRD patients. [ABSTRACT FROM AUTHOR]

The photoelectrochemical characteristic of semiconducting minerals plays an imperative role in supporting the growth of many electroactive microorganisms. In order to study the effects of photoelectrons triggered from semiconducting mineral by solar energy on the marine microbial growth, metabolism, and community structure, a dual-chamber electrochemical system was established by incubating seawater microbial community with varying simulated electrochemical conditions. The absolute quantifications of 16S rRNA and 18S rRNA genes suggested that photoelectrons could support the growth and reproduction of bacteria with an increase of two magnitudes from 1.34 ± 0.76 × 1012 to 1.41 ± 0.93 × 1014, and archaea with a slight increase from 0.50–8.74 × 1011 to 2.37–14.80 × 1011, whereas not for the growth of eukaryote in consideration of the complicated regulating mechanism of eukaryotic cells. The bacterial and archaeal communities were shaped by the supplement of photoelectron, also not for the eukaryotic community. Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria accounted for over 80% of the total bacterial community. Photoelectrons with appropriate energy could stimulate the diversity and maintain the community structure of bacteria and archaea while lower or higher electric potential caused lower diversity and more divergent microbial assemblages. The abundance of genes related to the electron transport chain was significantly higher in photoelectron regulated setups than that in open circuit ones, indicating that the extracellular photoelectrons experienced the transmembrane transition and entered the bacterial electron transport chain coupling cell anabolism and catabolism. This study proposed the potential impact of photoelectrons produced by semiconducting minerals on marine microorganisms and the putative electron flow under sunlight in the natural environments. [ABSTRACT FROM AUTHOR]

White savory(Satureja mutica Fisch & C.A.Mey.) is one of the most widely used medicinal plants in food processing, pharmaceutical and cosmetic industry due to the strongly scented and presence of phenolic compounds such as carvacrol and thymol. This experiment was carried out to evaluate the levels of inter and intra-populations variability of essential oil compositions of S. mutica grown in north of Iran. The essential oil was extracted by hydro-distillation method and analyzed using GC-FID and GC-MS apparatus. The results showed a high level of variation among individual plants of the studied populations based upon their essential oil production. The essential oil content ranged from 0.5 to 4.2%. thymol (6.5-74.6%), carvacrol (0.9-70.4%), borneol (0.1-38.0%), p-cymene (0.30-14.2%), and γ-terpinene (0.1-9.9%) were recognized as the major components of the all tested individual plants. Therefore, the variability identified here, might be considered as characterizing the large gene pool for breeding programs to comply the requirements of pharmaceutical and food industries.

Abstract Resins are one of the first sites of interaction between plants and biotic and abiotic factors. Despite their evident morphological and chemical differentiation from other plant organs, the detailed correlation between resins and biological or environmental factors is not yet clear. In this study, 1H nuclear magnetic resonance (NMR), gas chromatography coupled with mass spectrometry (GC-MS) and high-performance thin-layer chromatography (HPTLC)-based profiling techniques were applied to the metabolic characterisation of plant resins of different species and season of collection, using samples from five different species that were collected during early and late spring. The 1H NMR analysis confirmed the main metabolic groups in the resins to be terpenoids and further GC-MS analysis revealed a notable chemical variation between the species and collection periods. Abies grandis displayed a significant differentiation from the other species, showing a higher number of monoterpenes. The HPTLC-based profiling method hyphenated with multivariate data analysis (MVDA) also showed a clear separation confirming the GC-MS terpenoidal profiling results. Additionally, the unknown compounds were obtained by preparative TLC for identification. Based on the results of the three analytical platforms, it was concluded that the major difference in chemical composition of pine species was between species rather than the collection period. Nonetheless, the chemical profiles of resins from different species and collection periods can be well discriminated and correlated to mono- and sesquiterpenes in the case of species and diterpenes for the collection periods. Graphical abstract Image 1 Highlights • Pine resins of five species collected at different time points were analysed by metabolomics. • Terpenoids were the main variable metabolites. • Variation (principally in monoterpenes) between species was greater than between collection times. • High performance TLC was found to be an informative analytical technique for plant metabolomics. [ABSTRACT FROM AUTHOR]

Dietary restriction (DR)-related delay of ageing is hypothesized to be mediated by the reduction of the metabolic rate (MR). However, studies on the effect of DR on MR have produced equivocal results. We demonstrated that this lack of congruency can be due to a variation in the initial level of MR within a given pool of experimental subjects. We subjected laboratory mice from two line types divergently selected for basal MR (BMR) to 30% DR lasting 6 months to test whether the effect of DR depends on the initial variation in BMR and peak MR. BMR and peak MR were independently affected by DR. The effect of DR was stronger in line types with higher initial levels of MR. Line-type-specific changes in the proportions of body components explained contrasting effects of DR on the mass-corrected BMR, which decreased in the high-BMR line type and did not change in the low-BMR line type. We conclude that the initial variation in MR can significantly affect response to DR. However, we found no association between the level of MR and mechanisms underlying the susceptibility to or protection against oxidative stress. [ABSTRACT FROM AUTHOR]

The metabolome represents a critical aspect of a plant’s physiology, growth characteristics and, ultimately, economic value. Metabolic changes underpin plant development and responses to applied stresses, whilst quality traits in many important crops and ornamental plants are dependent on metabolic composition. It is also frequently reasoned that metabolic information reflects biological endpoints more accurately than transcript or protein analysis. As such, the science of metabolomics has proven to be of increasing popularity in assessing genotypic and phenotypic diversity in plants, in defining biochemical changes associated with developmental changes during plant growth and, increasingly, in compositional comparisons. The postulated value of this metabolic information resides primarily in its potential to support breeding and selection of novel yield-enhanced and nutritionally improved crops. Plants display remarkable genetic plasticity which has served to facilitate the development of an extraordinary range of genetically distinct and metabolically diverse cultivars for any given plant species. Despite concerns regarding potential loss of genetic diversity through domestication, genetic resources still exist through wild and exotic germplasms. Additionally, emerging biotechnological approaches such as RNAi silencing and the transgenic modification of regulatory genes offer new and fascinating opportunities for enhancing diversity and eliciting trait improvements. This review is intended to promote the view that metabolomics, through comparative assessments of metabolic diversity in domesticated and non-domesticated plants, and through evaluations of the compositional impact of metabolic engineering efforts can support breeding programmes designed to elicit trait improvements. [ABSTRACT FROM AUTHOR]

Within species, individuals of the same size can vary substantially in their metabolic rate. One source of variation in metabolism is conspecific density - individuals in denser populations may have lower metabolism than those in sparser populations. However, the mechanisms through which conspecifics drive metabolic suppression remain unclear. Although food competition is a potential driver, other density-mediated factors could act independently or in combination to drive metabolic suppression, but these drivers have rarely been investigated. We used sessile marine invertebrates to test how food availability interacts with oxygen availability, water flow and chemical cues to affect metabolism. We show that conspecific chemical cues induce metabolic suppression independently of food and this metabolic reduction is associated with the downregulation of physiological processes rather than feeding activity. Conspecific cues should be considered when predicting metabolic variation and competitive outcomes as they are an important, but underexplored, source of variation in metabolic traits., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2020. Published by The Company of Biologists Ltd.)

In order to determine the eythrolide content of Erythropodium caribaeorum from Islas del Rosario, 14 samples of this octocoral were collected in different locations of this sector. A metabolic profiling by NMR was conducted for all samples. The Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) of these NMR spectra allowed to stablish a great similarity between all samples. The chemical study of organic extract let us to identify the presence of erythrolide A (1) and B (2) as major compounds of samples collected at Islas del Rosario, and allowed us to propose a chemotype for these samples. The metabolic profile for Erythropodium caribaeorum collected at Islas del Rosario this samples is similar to those reported for samples collected at Jamaica, Tobago, Belize, Bahamas and Dominica. Additionally, this chemiotype is quite different from samples collected in Santa Marta. [ABSTRACT FROM AUTHOR]