Shift of Volatile Organic Compounds (VOCs) in Gluten-Free Hemp-Enriched Sourdough Bread: A Metabolomic Approach

Hemp seed flour represents a potential ingredient for protein enrichment of gluten-free bakery products, the nutritional value of which could be further increased by fermentation with sourdough or with beneficial lactic acid bacteria strains. In this study, a metabolomic approach was used to evaluate the effect of hemp seed flour addition and sourdough fermentation on the production of flavoring and health-related volatile organic compounds (VOCs) in a gluten-free bread. Multivariate analysis of VOCs provided an in-depth description of the effects of hemp seed flour addition and sourdough fermentation on flavoring and bioactive compounds. In particular, an increased concentration of antimicrobial compounds, a larger spectrum of bioactive VOCs and a typical flavoring profile was evidenced in comparison to standard products. Furthermore, an increase of fermentation metabolites was observed in comparison to a standard dough, relating to abundances of 2-butanone-3-hydroxy, acetic acid, ethanol, and 1,4-butanediol. This study provides new insights on the evolution of flavoring and bioactive hemp seed flour constituents during sourdough fermentation, evidencing their retention in baked goods, and describes a new approach that could guide the formulation of innovative, fermented food with enhanced nutritional value

Beneficial metabolic transformations and prebiotic potential of hemp bran and its alcalase hydrolysate, after colonic fermentation in a gut model

Hemp seed bran (HB) is an industrial food byproduct that is generally discarded. Knowledge on the functional capabilities of HB is limited and it is not known the impact of HB on human colon microbiota, where vegetable fibers are metabolized. In this work, we investigated in depth the prebiotic potential of HB and HB protein extract hydrolyzed by alcalase (HBPA) in comparison to fructooligosaccharides (FOS) after human distal colonic fermentation using MICODE (multi-unit in vitro colon gut model). During the 24 h of fermentation, metabolomics (SPME GC/MS) and microbiomics (MiSeq and qPCR) analyses were performed. The results indicated that HBPA on a colonic fermentation had a higher prebiotic index than HB (p < 0.05), and slightly lower to that of FOS (p > 0.05). This feature was described and explained as HBPA colonic fermentation produces beneficial organic fatty acids (e.g. Pentanoic and Hexanoic acids); reduces detrimental phenol derivates (e.g. p-Cresol); produces bioactives VOCs (e.g. Acetophenone or 4-Terpineol); increases beneficial bacteria (e.g. 1.76 fold and 2.07 fold more of Bifidobacterium bifidum and Bacteroides fragilis, respectively) and limits opportunistic bacteria (e.g. 3.04 fold and 2.07 fold less of Bilophila wadsworthia and Desulfovibrio, respectively). Our study evidenced the prebiotic role of HB and HBPA, and within the principles of OneHealth it valorizes a byproduct from the queen plant of sustainable crops as a food supplement

Multiunit In Vitro Colon Model for the Evaluation of Prebiotic Potential of a Fiber Plus D-Limonene Food Supplement

The search for new fiber supplements that can claim to be “prebiotic” is expanding fast, as the role of prebiotics and intestinal microbiota in well-being has been well established. This work explored the prebiotic potential of a novel fiber plus D-Limonene supplement (FLS) in comparison to fructooligosaccharides (FOS) over distal colonic fermentation with the in vitro model MICODE (multi-unit in vitro colon gut model). During fermentation, volatilome characterization and core microbiota quantifications were performed, then correlations among volatiles and microbes were interpreted. The results indicated that FLS generated positive effects on the host gut model, determining: (i) eubiosis; (ii) increased abundance of beneficial bacteria, as Bifidobacteriaceae; (iii) production of beneficial compounds, as n-Decanoic acid; (iv) reduction in detrimental bacteria, as Enterobaceteriaceae; (v) reduction in detrimental compounds, as skatole. The approach that we followed permitted us to describe the prebiotic potential of FLS and its ability to steadily maintain the metabolism of colon microbiota over time. This aspect is two-faced and should be investigated further because if a fast microbial turnover and production of beneficial compounds is a hallmark of a prebiotic, the ability to reduce microbiota changes and to reduce imbalances in the productions of microbial metabolites could be an added value to FLS. In fact, it has been recently demonstrated that these aspects could serve as an adjuvant in metabolic disorders and cognitive decline

Yeast-Free Doughs by Zymomonas mobilis: Evaluation of Technological and Fermentation Performances by Using a Metabolomic Approach

This research focuses on the leavening performances and development of volatile compounds of three strains of Zymomonas mobilis in the production of yeast-free doughs. Z. mobilis DSM 3580, 424, and 473 were used in doughs supplemented with glucose and with or without NaCl. Z. mobilis produced about 10 mg ethanol/g dough, with maximum dough volumes (640\u2013680 mL) being reached after 2 h leavening. NaCl addition postponed this parameter up to 6 h. Among organic acids, hexanoic acid resulted the highest produced compound; DSM 424 and 473 formed more propanoic, butanoic and pentanoic acid, being both negatively affected by NaCl. Esters were mainly discriminated on NaCl addition, with octanoic acid (DSM 3580), butanoic acid (DSM 424), and propanoic acid (DSM 473) ethyl esters as main components. DSM 3580 specifically produced 2-heptanal, DSM 424 2-hexadecenal, (E) and DSM 473 octanal, while DSM 424 and DSM 473 produced 2-butanone-4-hydroxy better than DSM 3580. Z. mobilis unique signatures were the production of nonanoic and undecanoic acids, 2-hexadecenal, (E), L(+)-tartaric acid diethyl ester and 3-decen-5-one, 4-methyl, (E). This outcome can pave the way for using Z. mobilis in baking goods, providing innovation possibilities in the area of yeast-free leavened products

Maternal amoxicillin affects piglets colon microbiota: microbial ecology and metabolomics in a gut model

The first weeks of life represent a crucial stage for microbial colonization of the piglets’ gastrointestinal tract. Newborns’ microbiota is unstable and easily subject to changes under stimuli or insults. Nonetheless, the administration of antibiotics to the sow is still considered as common practice in intensive farming for pathological conditions in the postpartum. Therefore, transfer of antibiotic residues through milk may occurs, affecting the piglets’ colon microbiota. In this study, we aimed to extend the knowledge on antibiotic transfer through milk, employing an in vitro dedicated piglet colon model (MICODE— Multi Unit In vitro Colon Model). The authors’ focus was set on the shifts of the piglets’ microbiota composition microbiom- ics (16S r-DNA MiSeq and qPCR—quantitative polymerase chain reaction) and on the production of microbial metabolites (SPME GC/MS—solid phase micro-extraction gas chromatography/mass spectrometry) in response to milk with different concentrations of amoxicillin. The results showed an effective influence of amoxicillin in piglets’ microbiota and metabolites production; however, without altering the overall biodiversity. The scenario is that of a limitation of pathogens and opportun- istic taxa, e.g., Staphylococcaceae and Enterobacteriaceae, but also a limitation of commensal dominant Lactobacillaceae, a reduction in commensal Ruminococcaceae and a depletion in beneficial Bifidobactericeae. Lastly, an incremental growth of resistant species, such as Enterococcaceae or Clostridiaceae, was observed. To the authors’ knowledge, this study is the first evaluating the impact of antibiotic residues towards the piglets’ colon microbiota in an in vitro model, opening the way to include such approach in a pipeline of experiments where a reduced number of animals for testing is employed

Micromeria thymifolia Essential Oil Suppresses Quorum-sensing Signaling in Pseudomonas aeruginosa

The chemical composition, antimicrobial and antiquorum sensing activity of the essential oil of Micromeria thymifolia (Scop.) Fritsch were investigated. Limonene, piperitone epoxide and piperitenone epoxide were found as the main constituents using a gas chromatography-mass spectrometry technique. In vitro antimicrobial activity of the oil was tested against six bacterial and seven fungal strains and high antimicrobial potential was noticed. Minimum inhibitory concentration varied from 0.031 mg/mL to 0.5 mg/mL for bacterial and 0.062 mg/mL to 0.5 mg/mL for fungal strains. The antiquorum properties of the essential oil were evaluated on Pseudomonas aeruginosa PAO1. The oil was tested at subMiC concentrations for anti-quorum sensing activity. The analyses on quorum-sensing functions have been carried out by evaluating twitching and swarming of bacterial cultures and the total amount of pyocyanin production produced by P. aeruginosa. This study showed that M thymifolia essential oil exhibited antiquorum sensing activity and may be used as an antipathogenic drug

Effect of cold plasma generated with different gas mixtures on safety, quality and nutritional aspects of fresh sea bream fillets

Cold atmospheric plasma (CAP) is a non-thermal technology, successfully used to decontaminate and extend the shelf-life of various foods. However, since CAP is highly oxidative, it can cause quality deterioration in sensitive matrices, such as fish products. This research aimed to evaluate the effect of CAP treatment with a surface dielectric barrier discharge (SDBD) with different gas mixtures (80% Ar/20% O2, or 80% N2/20% O2) on the decontamination of inoculated pathogens (E.coli and L.innocua; log 4 CFU/g inoculum) and endogenous spoilage microbiota and on the main quality indices of seabream (Spaurus aurata) fillets. For selected appropriate treatments, the impact on the nutritional value of the products was investigated through in vitro digestion, bioaccessibility of fatty acids and the degree of protein hydrolysis. The use of CAP resulted in a decrease in the bacterial load in the fresh sea bream fillets up to 1 log CFU/g obtained with Ar/O2 gas mixture for 20 min, affected by the treatment duration, but not by the gas mixture. Although a slight increase in lipid oxidation was observed (from 0.5 mg MDA/kg to a maximum of 4 mg MDA/kg), the digestibility of the products was not affected. Industrial relevance From an industrial point of view, increasing shelf-life of perishable products such as fish fillets with an environmentally friendly and non-thermal technology could represent a great advantage; however, maintaining quality is of paramount importance for the industrial use of this novel processing technology. The results of the present study show negligible effects on the nutritional quality of seabream fillets, which encourages further research.publishedVersio

Micromeria thymifolia Essential Oil Suppresses Quorum-sensing Signaling in Pseudomonas aeruginosa

The chemical composition, antimicrobial and antiquorum sensing activity of the essential oil of Micromeria thymifolia (Scop.) Fritsch were investigated. Limonene, piperitone epoxide and piperitenone epoxide were found as the main constituents using a gas chromatography-mass spectrometry technique. In vitro antimicrobial activity of the oil was tested against six bacterial and seven fungal strains and high antimicrobial potential was noticed. Minimum inhibitory concentration varied from 0.031 mg/mL to 0.5 mg/mL for bacterial and 0.062 mg/mL to 0.5 mg/mL for fungal strains. The antiquorum properties of the essential oil were evaluated on Pseudomonas aeruginosa PAO1. The oil was tested at subMiC concentrations for anti-quorum sensing activity. The analyses on quorum-sensing functions have been carried out by evaluating twitching and swarming of bacterial cultures and the total amount of pyocyanin production produced by P. aeruginosa. This study showed that M thymifolia essential oil exhibited antiquorum sensing activity and may be used as an antipathogenic drug

The Solar Twin Planet Search. V. Close-in, low-mass planet candidates and evidence of planet accretion in the solar twin HIP 68468

[Methods]. We obtained high-precision radial velocities with HARPS on the ESO 3.6 m telescope and determined precise stellar elemental abundances (~0.01 dex) using MIKE spectra on the Magellan 6.5m telescope. [Results]. Our data indicate the presence of a planet with a minimum mass of 26 Earth masses around the solar twin HIP 68468. The planet is a super-Neptune, but unlike the distant Neptune in our solar system (30 AU), HIP 68468c is close-in, with a semi-major axis of 0.66 AU, similar to that of Venus. The data also suggest the presence of a super-Earth with a minimum mass of 2.9 Earth masses at 0.03 AU; if the planet is confirmed, it will be the fifth least massive radial velocity planet discovery to date and the first super-Earth around a solar twin. Both isochrones (5.9 Gyr) and the abundance ratio [Y/Mg] (6.4 Gyr) indicate an age of about 6 billion years. The star is enhanced in refractory elements when compared to the Sun, and the refractory enrichment is even stronger after corrections for Galactic chemical evolution. We determined a NLTE Li abundance of 1.52 dex, which is four times higher than what would be expected for the age of HIP 68468. The older age is also supported by the low log(R'HK) (-5.05) and low jitter. Engulfment of a rocky planet of 6 Earth masses can explain the enhancement in both lithium and the refractory elements. [Conclusions]. The super-Neptune planet candidate is too massive for in situ formation, and therefore its current location is most likely the result of planet migration that could also have driven other planets towards its host star, enhancing thus the abundance of lithium and refractory elements in HIP 68468. The intriguing evidence of planet accretion warrants further observations to verify the existence of the planets that are indicated by our data and to better constrain the nature of the planetary system around this unique star.Comment: A&A, in pres

Telmisartan and Insulin Resistance in HIV (TAILoR):protocol for a dose-ranging phase II randomised open-labelled trial of Telmisartan as a strategy for the reduction of insulin resistance in HIV-positive individuals on combination antiretroviral therapy

Introduction Telmisartan, an angiotensin receptor blocker, has beneficial effects on insulin resistance and cardiovascular health in non-HIV populations. This trial will evaluate whether telmisartan can reduce insulin resistance in HIV-positive individuals on combination antiretroviral therapy. Methods and analysis This is a phase II, multicentre, randomised, open-labelled, dose-ranging trial of telmisartan in 336 HIV-positive individuals over a period of 48 weeks. The trial will use an adaptive design to inform the optimal dose of telmisartan. Patients will be randomised initially 1:1:1:1 to receive one of the three doses of telmisartan (20, 40 and 80 mg) or no intervention (control). An interim analysis will be performed when half of the planned maximum of 336 patients have been followed up for at least 24 weeks. The second stage of the study will depend on the results of interim analysis. The primary outcome measure is a reduction in insulin resistance (as measured by Homeostatic Model Assessment—Insulin Resistance (HOMA-IR)) in telmisartan treated arm(s) after 24 weeks of treatment in comparison with the non-intervention arm. The secondary outcome measures include changes in lipid profile; body fat redistribution (as measured by MRI); plasma and urinary levels of various biomarkers of cardiometabolic and renal health at 12, 24 and 48 weeks. Serious adverse events will be compared between different telmisartan treated dose arm(s) and the control arm. Ethics and dissemination The study, this protocol and related documents have been approved by the National Research Ethics Service Committee North West—Liverpool Central (Ref: 12/NW/0214). On successful completion, study data will be shared with academic collaborators. The findings from TAILoR will be disseminated through peer-reviewed publications, at scientific conferences, the media and through patient and public involvement. Trial registration numbers 04196/0024/001-0001; EUDRACT: 2012-000935-18; ISRCTN: 51069819