Estuarine hydrodynamic processes driving the molecular changes of terrestrial dissolved organic nitrogen: From mixing to biological modification.

Estuaries receive substantial amounts of terrestrial dissolved organic nitrogen (tDON), which will be transported from the freshwater to the oceanic terminus through vigorous exchange processes. However, the intricate migration and transformation dynamics of tDON during this transportation, particularly at a molecular level, remain constrained. To address this knowledge gap, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) was used for the analysis of DON molecular composition in the Pearl River Estuary (PRE), a river-dominated estuarine system influenced by intensified anthropogenic activities in southern China. The results showed a pronounced spatial-temporal variation in DON concentration in the study area. At the molecular level, tDON exhibited reduced unsaturation and aromaticity, coupled with an elevated abundance of DON compounds containing one­nitrogen atom (1 N-DON, 53.17 %) and compounds containing carbon, hydrogen, oxygen, nitrogen, and sulfur (CHONS) (27.46 %). It was evident that lignin was depleted while more oxygenated tannin compounds were generated in the freshwater-seawater mixing zone. This transformation is attributed to heightened biological activities, likely influenced by the priming effect of terrestrial nutrient inputs. In summer, the prevailing plume combined with biological activities in the strong mixing area and outer estuary increased the abundance of 3 N-DON molecules and a concurrent rise in the abundance of DON compounds containing only carbon, hydrogen, oxygen, and nitrogen (CHON), DON compounds containing carbon, hydrogen, oxygen, nitrogen, sulfur, and phosphorus (CHONSP), and CHONS. This trend also underscores the expanding role of marine plankton and microbes in the utilization of DON compounds containing carbon, hydrogen, oxygen, nitrogen, and phosphorus (CHONP). These findings provide details of tDON transformation processes at the molecular level in a river-dominated estuary and underline the estuarine hydrodynamics involved in transporting and altering DON within the estuary.

The key phytochemistry of rosemary (Salvia rosmarinus) contributing to hair protection against UV.

Extracts from rosemary (Salvia Rosmarinus) are analysed for their phytochemistry using LC-MS and the phytochemistry identified. The same extracts were tested for their efficacy to act as antioxidants by both hydrogen-atom transfer (ORAC) and single electron transfer (FRAP). A correlation analysis was performed to identify the key phytochemistry responsible for antioxidant efficacy. The top performing extracts were then tested in a peptide model and in hair with the presence of UV to measure ability to protect against UV-induced peptide and protein damage. Polyphenols (e.g. rosmarinic acid, glycosides of selgin) and abietane diterpenes (e.g. carnosic acid) in rosemary were identified as the principal compounds which enables the extracts to protect hair from UV. OBJECTIVE: The objective of this work was to correlate the phytochemistry of rosemary (Salvia rosmarinus), a botanical with known antioxidant properties, to a UV protection benefit in hair. These data will give insights into mechanisms of UV damage, the ROS formed and their reactivity. METHODS: LC-MS was used to compare the compounds in 10 commercial extracts of rosemary. ORAC (oxygen radical antioxidant capacity) and FRAP (ferric reducing antioxidant power) were used to measure the antioxidant capacity of the rosemary extracts. The ORAC assay measures ability of an antioxidant to react with a peroxyl radical via hydrogen atom extraction and FRAP measures electron transfer through reduction of ferric iron (Fe3+ ) to ferrous iron (Fe2+ ) by antioxidants present in the samples. Correlation of extract composition with antioxidant measures was performed using principal component analysis. Selected extracts were assessed for their ability to protect hair from UV damage in a model peptide system and on hair. In addition, the same methods were used to test rosmarinic acid and carnosic acid, key phytochemistries in the rosemary extracts. The model system was a peptide and its decomposition on exposure to UV was monitored by LC-MS in the absence and presence of the rosemary extracts. Hair degradation in the presence of UV was measured by exposure of UV in an Atlas weatherometer followed by extraction of degraded protein in water. A fragment of the S100A3 protein was used as a marker of UV damage (m/z = 1278) and quantified via LC-MS. RESULTS: Ten rosemary extracts were assessed for antioxidant performance and correlated with their compositions. The phytochemistry in each extract varied widely with a total of 33 individual compounds identified. The differences were most likely driven by the solvent and extraction method used by the supplier with extracts varying in the proportion of polar or non-polar compounds. This did influence their reactivity in the ORAC and FRAP assays and their efficacy in preventing protein damage. Two of the key compounds identified were rosmarinic acid and carnosic acid, with rosmarinic acid dominating in extracts with mainly polar compounds and carnosic acid dominating in extracts with mainly nonpolar compounds. Extracts with higher rosmarinic acid correlated with ORAC and FRAP scores, with UV protection on hair and in the peptide model system. The extracts chosen for hair experiments showed hair protection. UV protection was also measured for rosmarinic and carnosic acid. CONCLUSIONS: Despite the variation in the profile of phytochemistries in the 10 rosemary extracts, likely driven by the chosen extraction method, all rosemary extracts had antioxidant activity measured. This study suggests that the polyphenols (e.g. rosmarinic acid, glycosides of selgin) and abietane diterpenes (e.g. carnosic acid) are the principal compounds which enables the extracts to protect hair from UV.

INTRODUCTION: Les extraits de romarin (Salvia Rosmarinus) sont analysés par LC-MS pour établir et identifier leur profil phytochimique. Les mêmes extraits ont été testés pour leur efficacité à agir comme antioxydants à la fois par transfert d'atome d'hydrogène (ORAC) et par transfert d'électrons uniques (FRAP). Une analyse de corrélation a été réalisée pour identifier les propriétés phytochimiques clés responsables de l'efficacité antioxydante. Les extraits les plus performants ont ensuite été testés dans un modèle peptidique et sur les cheveux en présences d'UV pour mesurer la capacité à protéger contre les dommages induits par les UV su les peptides et protéines. Les polyphénols (par ex. acide rosmarinique, glycosides de selgin) et les diterpènes d'abiétine (par ex. acide carnosique) dans le romarin ont été identifiés comme les principaux composés permettant aux extraits de protéger les cheveux des UV. OBJECTIF: L'objectif de ce travail était de mettre en corrélation la phytochimie du romarin (Salvia rosmarinus), une plante aux propriétés antioxydantes connues, et les bénéfices d'une protection contre les UV dans les cheveux. Ces données fourniront des informations sur les mécanismes des dommages causés par les UV, la formation du ROS et leur réactivité. MÉTHODES: La LC-MS a été utilisée pour comparer les composés de 10 extraits commerciaux de romarin. L'ORAC (Oxygen Radical Antioxidant Capacity/Capacité d'absorption des radicaux d'oxygène) et la FRAP (Ferric Reduction Antioxidant Power/Pouvoir antioxydant de réduction ferrique) ont été utilisés pour mesurer la capacité antioxydante des extraits de romarin. Le dosage ORAC mesure la capacité d'un antioxydant à réagir avec un radical peroxyl par extraction d'atome d'hydrogène et la FRAP mesure le transfert d'électrons par réduction du fer ferrique (Fe3+ ) en fer ferreux (Fe2+ ) par les antioxydants présents dans les échantillons. La corrélation entre la composition de l'extrait et les mesures des antioxydants a été effectuée en analysant les composants principaux. Les extraits sélectionnés ont été évalués pour leur capacité à protéger les cheveux des dommages causés par les UV dans un modèle de système peptidique et sur les cheveux. En outre, les mêmes méthodes ont été utilisées pour tester l'acide rosmarinique et l'acide carnosique, principales caractéristiques phytochimiques dans les extraits de romarin. Le système modèle était un peptide et sa décomposition à l'exposition aux UV a été suivie par LC-MS en l'absence et en présence des extraits de romarin. La dégradation des cheveux en présence d'UV a été mesurée par l'exposition aux UV dans un indicateur de désagrégation Atlas suivi de l'extraction de protéines dégradées dans l'eau. Un fragment de la protéine S100A3 a été utilisé comme marqueur de dommage UV (m/z = 1278) et quantifié par LC-MS. RÉSULTATS: Dix extraits de romarin ont été évalués en termes de performance antioxydante et mis en corrélation avec leurs compositions. La phytochimie de chaque extrait variait considérablement, avec un total de 33 composés individuels identifiés. Les différences étaient très probablement dues à la méthode du solvant et de l'extraction utilisée par le fournisseur avec des extraits variant dans la proportion de composés polaires ou non polaires. Cela a effectivement influencé leur réactivité dans les dosages ORAC et FRAP et leur efficacité dans la prévention des dommages protéiques. Deux des composés clés identifiés étaient l'acide rosmarinique et l'acide carnosique, l'acide rosmarinique dominant dans les extraits contenant principalement des composés polaires et l'acide carnosique dominant dans les extraits contenant principalement des composés non polaires. Les extraits avec un taux d'acide rosmarinique plus élevé étaient mis en corrélation avec les scores ORAC et FRAP, avec une protection UV sur les cheveux et dans le système de modèle peptidique. Les extraits choisis pour les expériences sur les cheveux ont montré une protection des cheveux. La protection contre les UV a également été mesurée pour l'acide rosmarinique et l'acide carnosique. CONCLUSIONS: Malgré la variation des profils phytochimiques dans les dix extraits de romarin, probablement induite par la méthode d'extraction choisie, l'activité antioxydante de tous les extraits de romarin a été mesurée. Les polyphénols (par ex. acide rosmarinique, glycosides de selgin) et les diterpènes d'abiétane (par ex. acide carnosique) dans le romarin ont été identifiés comme les principaux composés permettant aux extraits de protéger les cheveux contre les UV.

Dark fermentative hydrogen production: Potential of food waste as future energy needs.

Globally, food waste (FW) is found to be one of the major constituents creating several hurdles in waste management. On the other hand, the energy crisis is increasing and the limited fossil fuel resources available are not sufficient for energy needed for emerging population. In this context, biohydrogen production approach through valorization of FW is emerging as one of the sustainable and eco-friendly options. The present review explores FW sources, characteristics, and dark fermentative production of hydrogen along with its efficiency. FW are highly biodegradable and rich in carbohydrates which can be efficiently utilized by anaerobic bacteria. Based on the composition of FW, several pretreatment methods can be adapted to improve the bioavailability of the organics. By-products of dark fermentation are organic acids that can be integrated with several secondary bioprocesses. The versatility of secondary products is ranging from energy generation to biochemicals production. Integrated approaches facilitate in enhanced energy harvesting along with extended wastewater treatment. The review also discusses various parameters like pH, temperature, hydraulic retention time and nutrient supplementation to enhance the process efficiency of biohydrogen production. The application of solid-state fermentation (SSF) in dark fermentation improves the process efficiency. Dark fermentation as the key process for valorization and additional energy generating process can make FW the most suitable substrate for circular economy and waste based biorefinery.

Performance and mechanism of sacrificed iron anode coupled with constructed wetlands (E-Fe) for simultaneous nitrogen and phosphorus removal.

Three anodic biofilm electrode coupled CWs (BECWs) with graphite (E-C), aluminum (E-Al), and iron (E-Fe), respectively, and a control system (CK) were constructed to evaluate the removal performance of N and P in the secondary effluent of wastewater treatment plants (WWTPs) under different hydraulic retention time (HRT), electrified time (ET), and current density (CD). Microbial communities, and different P speciation, were analyzed to reveal the potential removal pathways and mechanism of N and P in BECWs. Results showed that the optimal average TN and TP removal rates of CK (34.10% and 55.66%), E-C (66.77% and 71.33%), E-Al (63.46% and 84.93%), and E-Fe (74.93% and 91.22%) were obtained under the optimum conditions (HRT 10 h, ET 4 h, CD 0.13 mA/cm2), which demonstrated that the biofilm electrode could significantly improve N and P removal. Microbial community analysis showed that E-Fe owned the highest abundance of chemotrophic Fe(II) (Dechloromonas) and hydrogen autotrophic denitrifying bacteria (Hydrogenophaga). N was mainly removed by hydrogen and iron autotrophic denitrification in E-Fe. Moreover, the highest TP removal rate of E-Fe was attributed to the iron ion formed on the anode, causing co-precipitation of Fe(II) or Fe(III) with PO43--P. The Fe released from the anode acted as carriers for electron transport and accelerated the efficiency of biological and chemical reactions to enhance the simultaneous removal of N and P. Thus, BECWs provide a new perspective for the treatment of the secondary effluent from WWTPs.

Discovery of a triphenylamine-benzofuran derivative as fluorescent probe for hydrogen polysulfide in tea samples.

In this work, a novel triphenylamine-benzofuran derived fluorescent probe, TBF-SS, was developed for detecting hydrogen polysulfide in tea samples and intracellular imaging. TBF-SS showed the practical advantages including high sensitivity (LOD = 0.01 µM), high selectivity, rapid response (within 15 min), and steadiness in various environmental conditions. The detecting system was steady within pH range of 6.0-11.0 and temperature range of 20-55 °C. The probe TBF-SS could guarantee the stable detection of H2Sn for 7 d in storage of either solid or solution. In particular, in the application of various tea samples with different brewing times and testing temperatures, the recovery percentages varied in the range of 95.22 % to 105.0 %. Therefore accurate monitoring of H2Sn could be achieved by using the probe TBF-SS. In addition, TBF-SS could monitor the exogenous level, the ß-lapachone-induced generation and the tea-sample-treated introduction of H2Sn in living MCF-7 cells. This work might inspire the improvement of the serviceability of fluorescent implements.

Stability of valeriana-type iridoid glycosides from rhizomes of Nardostachys jatamansi and their protection against H2O2-induced oxidative stress in SH-SY5Y cells.

Nardostachys jatamansi is close to Valerian in consideration of their same psychoactive effects, such as sedation and neuroprotection. Valeriana-type iridoids are major active components of Valerian, but few valeriana-type iridoids have been isolated from N. jatamansi. Iridoid-targeting chemical investigation of the rhizomes of N. jatamansi resulted in the isolation of seven valeriana-type iridoid glycosides, four of which are previously undescribed. Their structures were determined through NMR spectroscopy, high-resolution mass spectrometry, and optical rotation experiments. In addition, the inaccurate configurations of patrinalloside and 6″-acetylpatrinalloside from previous reports were corrected. These compounds, unstable due to alcoholic solvents, were more stable in the mixtures than in purified forms, as monitored by the qNMR method, supporting the use of natural products as mixtures. Furthermore, the isolates, as well as crude and solvent partition extracts, were found to have a protective effect against hydrogen-peroxide-induced toxicity in human neuroblastoma cells, as confirmed by assays for cell viability and antioxidation. These findings suggest the potential therapeutic application of the valeriana-type iridoid glycosides isolated herein with improved biochemical stability.

Concept design, technical performance, and GHG emissions analysis of petroleum coke direct chemical looping hydrogen highly integrated with gasification for methanol production process.

Petroleum coke gasification for methanol production process has excellent application prospects for the clean utilization of high­sulfur coke while limiting pollutant emissions from coke combustion. However, the process still suffers from high-energy use and a large CO2 generation caused by composition adjustment. This study proposes a novel petroleum coke chemical looping hydrogen-assisted gasification process for methanol production. Mass-energy coupling is realized by replacing the water gas shift unit with the chemical looping hydrogen unit, and the high temperature gasified gas heats the fuel reactor and in turn the feedstock. Two chemical looping hydrogen scenarios with an operating pressure of 3.0 and 0.1 MPa are considered. The methanol exergy can be increased from 484 to 1030 and 1028 MW by doubling the petroleum coke consumption through the chemical looping integration. The exergy efficiency of the new process is correspondingly increased from 51.6 to 57.1 and 55.2 % with 63.02 and 63.71 % reductions in direct CO2 emissions, as compared to the only gasification route. The calculated life cycle energy consumption and greenhouse gases emissions of the new processes are 40.02/43.84 GJ/t and 693/1055 kg CO2 eq/t, 15.14/7.05 % and 49.09/22.45 % lower than that of the benchmark process. The integration of high-pressure chemical looping technology can introduce significant technical and environmental benefits for methanol production from the petroleum coke.

Establishment of the upstream processing for renewable production of hydrogen using vermicomposting-tea and molasses as substrate.

This study aimed to establish the optimal operational conditions for hydrogen production using vermicomposting-tea and sugarcane molasses as substrate. The experiments were carried out by triplicate in 110 ml serological bottles, a Box-Behnken design of experiments was performed in anaerobic dark conditions. The maximal hydrogen production (HP), hydrogen production rate (HPR), and hydrogen yield (HY) attained were 1021.0 mlL-1, 5.32 mlL-1h-1, and 60.3 mlLH2-1/gTCC, respectively. The statistical model showed that the optimal operational conditions for pH, molasses concentration, and temperature were 6.5; 30 % (v/v) and 25 °C. The bioreactor run showed 17.202 L of hydrogen, 0.58 Lh-1, and 77.2 mlH2gTCC-1 For HP, HPR, and HY. Chemometric analysis for the volatile fatty acids obtained at the fermentation showed that only two principal components are required to explain 90 % of the variance. The representative pathways for hydrogen production were acetic and butyric acids. This study established the operational conditions for the upstream processing amenable to pilot and industrial-scale operations. Our results add value to molasses within the circular economy for hydrogen production using a novel consortium from vermicompost.

A high-temperature water vapor equilibration method to determine non-exchangeable hydrogen isotope ratios of sugar, starch and cellulose.

The analysis of the non-exchangeable hydrogen isotope ratio (δ2 Hne ) in carbohydrates is mostly limited to the structural component cellulose, while simple high-throughput methods for δ2 Hne values of non-structural carbohydrates (NSC) such as sugar and starch do not yet exist. Here, we tested if the hot vapor equilibration method originally developed for cellulose is applicable for NSC, verified by comparison with the traditional nitration method. We set up a detailed analytical protocol and applied the method to plant extracts of leaves from species with different photosynthetic pathways (i.e., C3 , C4 and CAM). δ2 Hne of commercial sugars and starch from different classes and sources, ranging from -157.8 to +6.4‰, were reproducibly analysed with precision between 0.2‰ and 7.7‰. Mean δ2 Hne values of sugar are lowest in C3 (-92.0‰), intermediate in C4 (-32.5‰) and highest in CAM plants (6.0‰), with NSC being 2 H-depleted compared to cellulose and sugar being generally more 2 H-enriched than starch. Our results suggest that our method can be used in future studies to disentangle 2 H-fractionation processes, for improving mechanistic δ2 Hne models for leaf and tree-ring cellulose and for further development of δ2 Hne in plant carbohydrates as a potential proxy for climate, hydrology, plant metabolism and physiology.

Psyllium reduces inulin-induced colonic gas production in IBS: MRI and in vitro fermentation studies.

OBJECTIVE: Health-promoting dietary fibre including inulin often triggers gastrointestinal symptoms in patients with IBS, limiting their intake. Our aim was to test if coadministering psyllium with inulin would reduce gas production. DESIGN: A randomised, four-period, four-treatment, placebo-controlled, crossover trial in 19 patients with IBS. Subjects ingested a 500 mL test drink containing either inulin 20 g, psyllium 20 g, inulin 20 g+ psyllium 20 g or dextrose 20 g (placebo). Breath hydrogen was measured every 30 min with MRI scans hourly for 6 hours. Faecal samples from a subset of the patients with IBS were tested using an in vitro fermentation model. Primary endpoint was colonic gas assessed by MRI. RESULTS: Colonic gas rose steadily from 0 to 6 hours, with inulin causing the greatest rise, median (IQR) AUC(0-360 min) 3145 (848-6502) mL·min. This was significantly reduced with inulin and psyllium coadministration to 618 (62-2345) mL·min (p=0.02), not significantly different from placebo. Colonic volumes AUC(0-360 min) were significantly larger than placebo for both inulin (p=0.002) and inulin and psyllium coadministration (p=0.005). Breath hydrogen rose significantly from 120 min after inulin but not psyllium; coadministration of psyllium with inulin delayed and reduced the maximum increase, AUC(0-360 min) from 7230 (3255-17910) ppm·hour to 1035 (360-4320) ppm·hour, p=0.007.Fermentation in vitro produced more gas with inulin than psyllium. Combining psyllium with inulin did not reduce gas production. CONCLUSIONS: Psyllium reduced inulin-related gas production in patients with IBS but does not directly inhibit fermentation. Whether coadministration with psyllium increases the tolerability of prebiotics in IBS warrants further study. TRIAL REGISTRATION NUMBER: NCT03265002.

Heat-retention effects of hydrogen-rich water bath assessed by thermography for humans.

Hydrogen-rich water bath devices are commercially available, but have been scarcely clarified for heat-retention effects. In this study, heat-retention effects of hydrogen-rich water bath were assessed by thermographic clinical trials, which employed twenty-four healthy subjects. The thermograms indicated that, under the same conditions (41 °C, 10-min bathing), hydrogen-rich water bath (hydrogen concentrations: 185-548 µg/L; oxidation-reduction potentials: -167 to -91 mV, versus 0.8 µg/L and +479 mV for normal bath, respectively) brought about the heat-retention being more marked than those of normal water bath for several body-parts in the order as follows: abdomen > upper legs > arms > hands > feet, for 30- and 60-min post-bathing, being in contrast to scarce heat-retention for head, armpits and lower legs. Then, as reflection to promotive effects on blood stream, we also examined the thickness of fingertip-capillary in hands. The thickness was expanded in the hydrogen-rich water bath more markedly than that in the normal water bath, suggesting that the hydrogen-rich water bath may have the hydrogen-based promotive effect, exceeding over mere heat retention-based effects, on blood circulation of the whole body. Meanwhile, the heat-retention in hydrogen-rich water bath weakly or moderately correlated with contents of the subcutaneous fat, whole body fat and body mass index, and inversely correlated with skeletal muscle rates, although their correlation degrees did not obviously exceed over normal water bath, with a poor relation with the basal metabolism rate. Thus, the hydrogen-rich water bath was suggested to exert heat-retention effects exceeding over normal water bath, in diverse body-parts such as abdomen, upper legs, arms and hands, via promotion to blood flow which was reflected by expanding the thickness of capillary. The heat-retention after bathing can be noted as effects of the hydrogen-rich water bath, which is applicable for most of people widespread regardless of their body composition index.

Fossil leaf wax hydrogen isotopes reveal variability of Atlantic and Mediterranean climate forcing on the southeast Iberian Peninsula between 6000 to 3000 cal. BP.

Many recently published papers have investigated the spatial and temporal manifestation of the 4.2 ka BP climate event at regional and global scales. However, questions with regard to the potential drivers of the associated climate change remain open. Here, we investigate the interaction between Atlantic and Mediterranean climate forcing on the south-eastern Iberian Peninsula during the mid- to late Holocene using compound-specific hydrogen isotopes from fossil leaf waxes preserved in marine sediments. Variability of hydrogen isotope values in the study area is primarily related to changes in the precipitation source and indicates three phases of increased Mediterranean sourced precipitation from 5450 to 5350 cal. BP, from 5150 to 4300 cal. BP including a short-term interruption around 4800 cal. BP, and from 3400 to 3000 cal. BP interrupted around 3200 cal. BP. These phases are in good agreement with times of prevailing positive modes of the North Atlantic Oscillation (NAO) and reduced storm activity in the Western Mediterranean suggesting that the NAO was the dominant modulator of relative variability in precipitation sources. However, as previously suggested other modes such as the Western Mediterranean Oscillation (WeMO) may have altered this overall relationship. In this regard, a decrease in Mediterranean moisture source coincident with a rapid reduction in warm season precipitation during the 4.2 ka BP event at the south-eastern Iberian Peninsula might have been related to negative WeMO conditions.

Inhaled H2 or CO2 Do Not Augment the Neuroprotective Effect of Therapeutic Hypothermia in a Severe Neonatal Hypoxic-Ischemic Encephalopathy Piglet Model.

Hypoxic-ischemic encephalopathy (HIE) is still a major cause of neonatal death and disability as therapeutic hypothermia (TH) alone cannot afford sufficient neuroprotection. The present study investigated whether ventilation with molecular hydrogen (2.1% H2) or graded restoration of normocapnia with CO2 for 4 h after asphyxia would augment the neuroprotective effect of TH in a subacute (48 h) HIE piglet model. Piglets were randomized to untreated naïve, control-normothermia, asphyxia-normothermia (20-min 4%O2-20%CO2 ventilation; Tcore = 38.5 °C), asphyxia-hypothermia (A-HT, Tcore = 33.5 °C, 2-36 h post-asphyxia), A-HT + H2, or A-HT + CO2 treatment groups. Asphyxia elicited severe hypoxia (pO2 = 19 ± 5 mmHg) and mixed acidosis (pH = 6.79 ± 0.10). HIE development was confirmed by altered cerebral electrical activity and neuropathology. TH was significantly neuroprotective in the caudate nucleus but demonstrated virtually no such effect in the hippocampus. The mRNA levels of apoptosis-inducing factor and caspase-3 showed a ~10-fold increase in the A-HT group compared to naïve animals in the hippocampus but not in the caudate nucleus coinciding with the region-specific neuroprotective effect of TH. H2 or CO2 did not augment TH-induced neuroprotection in any brain areas; rather, CO2 even abolished the neuroprotective effect of TH in the caudate nucleus. In conclusion, the present findings do not support the use of these medical gases to supplement TH in HIE management.

Geothermal industry waste-derived catalyst for enhanced biohydrogen production.

The main aim of this work was to develop sustainable catalyst from geothermal waste by hydrothermal process for enhanced biohydrogen production. The effects of Si/Al ratio and pH neutralization on the catalyst were also investigated to provide further insight into the hydrogen production capability. Results have shown with increasing Si/Al ratio, a lower amount of catalyst was synthesized and smaller particle size was obtained. pH neutralization treatment resulted in higher conversion compared to non-neutralized ones. Meanwhile, the highest conversion of biohydrogen from ethanol through steam reforming process (95.19%) was obtained from catalyst with pH neutralization treatment and Si/Al ratio of 10. The catalyst developed in this study was concluded to be suitable for framework/supporting catalyst due to relatively low selectivity.

Sauna, sweat and science II - do we sweat what we drink?

Inspired by a previous 'Sauna, sweat and science' study [Zech et al. Isot Environ Health Stud. 2015;51(3):439-447] and out of curiosity and enthusiasm for stable isotope and sauna research we aimed at answering the question 'do we sweat (isotopically) what we drink'? We, therefore, pulse-labelled five test persons in a sauna experiment with beverages that were 2H-enriched at about +25,600 ‰. Sweat samples were collected during six sauna rounds and the hydrogen isotope composition δ2Hsweat was determined using an isotope ratio mass spectrometer. Before pulse labelling, δ2Hsweat - reflecting by approximation body water - ranged from -32 to -22 ‰. This is ∼35 ‰ enriched compared to usual mid-European drinking water and can be explained with hydrogen-bearing food as well as with the respiratory loss of 2H-depleted vapour. The absence of a clearly detectable 2H pulse in sweat after pulse labelling and δ2Hsweat results of ≤+250 ‰ due to a fast 2H equilibration with body water are moreover a clearly negative answer to our research question also in a short-term consideration. Given that the recovery of the tracer based on an isotope mass balance calculation is clearly below 100 %, we finally answer the question 'where did the rest of the tracer go?'

Discrimination of Geographical Origin of Asian Garlic Using Isotopic and Chemical Datasets under Stepwise Principal Component Analysis.

Isotopic compositions of δ2 H, δ18 O, δ13 C, and δ15 N and concentrations of 22 trace elements from garlic samples were analyzed and processed with stepwise principal component analysis (PCA) to discriminate garlic's country of origin among Asian regions including South Korea, Vietnam, Taiwan, and China. Results indicate that there is no single trace-element concentration or isotopic composition that can accomplish the study's purpose and the stepwise PCA approach proposed does allow for discrimination between countries on a regional basis. Sequentially, Step-1 PCA distinguishes garlic's country of origin among Taiwanese, South Korean, and Vietnamese samples; Step-2 PCA discriminates Chinese garlic from South Korean garlic; and Step-3 and Step-4 PCA, Chinese garlic from Vietnamese garlic. In model tests, countries of origin of all audit samples were correctly discriminated by stepwise PCA. Consequently, this study demonstrates that stepwise PCA as applied is a simple and effective approach to discriminating country of origin among Asian garlics.

Anaerobic biodegradation of dissolved ethanol in a pilot-scale sand aquifer: Variability in plume (redox) biogeochemistry.

The use of ethanol in alternative fuels has led to contamination of groundwater with high concentrations of this easily biodegradable organic compound. Previous laboratory and field studies have shown vigorous biodegradation of ethanol plumes, with prevalence of reducing conditions and methanogenesis. The objective of this study was to further our understanding of the dynamic biogeochemistry processes, especially dissolved gas production, that may occur in developing and aging plume cores at sites with ethanol or other organic contamination of groundwater. The experiment performed involved highly-detailed spatial and temporal monitoring of ethanol biodegradation in a 2-dimensional (175cm high×525cm long) sand aquifer tank for 330days, with a vertical shift in plume position and increased nutrient inputs occurring at ~Day 100. Rapid onset of fermentation, denitrification, sulphate-reduction and iron(III)-reduction occurred following dissolved ethanol addition, with the eventual widespread development of methanogenesis. The detailed observations also demonstrate a redox zonation that supports the plume fringe concept, secondary reactions resulting from a changing/moving plume, and time lags for the various biodegradation processes. Additional highlights include: i) the highest dissolved H2 concentrations yet reported for groundwater, possibly linked to vigorous fermentation in the absence of common terminal electron-acceptors (i.e., dissolved oxygen, nitrate, and sulphate, and iron(III)-minerals) and methanogenesis; ii) evidence of phosphorus nutrient limitation, which stalled ethanol biodegradation and perhaps delayed the onset of methanogenesis; and iii) the occurrence of dissimilatory nitrate reduction to ammonium, which has not been reported for ethanol biodegradation to date.

Fructans Exacerbate Symptoms in a Subset of Children With Irritable Bowel Syndrome.

BACKGROUND & AIMS: Dietary fructans exacerbate symptoms in some, but not all, adults with irritable bowel syndrome (IBS). We sought to determine whether fructans worsen symptoms in children with IBS and whether clinical and psychosocial factors, and/or gas production, can identify those who are fructan sensitive. METHODS: We performed a double-blind placebo-controlled (maltodextrin) cross-over trial of 23 children with IBS, based on pediatric Rome III criteria, from September 2014 through December 2016. At baseline, participants completed 1-week pain and stool diaries and a 3-day food record and psychosocial factors (depression, anxiety, and somatization) were measured. Subjects were randomly assigned to groups that were provided meals for 72 hours containing either fructans or maltodextrin (0.5 g/kg; maximum, 19 g). Following a washout period of 10 days or more, the subjects received the meal they were not given during the first study period (crossed over). Gastrointestinal symptoms and breath hydrogen and methane production were captured during each meal period. Fructan sensitivity was defined as an increase of 30% or more in abdominal pain frequency following fructan ingestion. RESULTS: Subjects had more mean episodes of abdominal pain/day during the fructan-containing diet (3.4 ± 2.6) vs the maltodextrin-containing diet (2.4 ± 1.7) (P < .01), along with more severe bloating (P < .05) and flatulence (P = .01). Hydrogen (but not methane) production was greater while subjects were on the fructan-containing diet (617 ± 305 ppm∗h) than the maltodextrin-containing diet (136 ± 78 ppm*h) (P < .001). Eighteen subjects (78.2%) had more frequent abdominal pain while on the fructan-containing diet and 12 (52.2%) qualified as fructan sensitive. We found no difference between fructan-sensitive and fructan-insensitive subjects in baseline abdominal pain or bowel movement characteristics, dietary intake, psychosocial parameters, IBS subtype, or gas production. CONCLUSIONS: In a randomized controlled trial of children with IBS, we found fructans to exacerbate several symptoms. However, fructan sensitivity cannot be identified based on baseline gastrointestinal symptoms, dietary intake, psychosocial factors, or gas production. Clinicaltrials.gov no: NCT02842281.

Biohydrogen production from sugarcane bagasse hydrolysate: effects of pH, S/X, Fe2+, and magnetite nanoparticles.

Batch dark fermentation experiments were conducted to investigate the effects of initial pH, substrate-to-biomass (S/X) ratio, and concentrations of Fe2+ and magnetite nanoparticles on biohydrogen production from sugarcane bagasse (SCB) hydrolysate. By applying the response surface methodology, the optimum condition of steam-acid hydrolysis was 0.64% (v/v) H2SO4 for 55.7 min, which obtained a sugar yield of 274 mg g-1. The maximum hydrogen yield (HY) of 0.874 mol (mol glucose-1) was detected at the optimum pH of 5.0 and S/X ratio of 0.5 g chemical oxygen demand (COD, g VSS-1). The addition of Fe2+ 200 mg L-1 and magnetite nanoparticles 200 mg L-1 to the inoculum enhanced the HY by 62.1% and 69.6%, respectively. The kinetics of hydrogen production was estimated by fitting the experimental data to the modified Gompertz model. The inhibitory effects of adding Fe2+ and magnetite nanoparticles to the fermentative hydrogen production were examined by applying Andrew's inhibition model. COD mass balance and full stoichiometric reactions, including soluble metabolic products, cell synthesis, and H2 production, indicated the reliability of the experimental results. A qPCR-based analysis was conducted to assess the microbial community structure using Enterobacteriaceae, Clostridium spp., and hydrogenase-specific gene activity. Results from the microbial analysis revealed the dominance of hydrogen producers in the inoculum immobilized on magnetite nanoparticles, followed by the inoculum supplemented with Fe2+ concentration. Graphical abstract ᅟ.

Bionanofiber Assisted Decoration of Few-Layered MoSe2 Nanosheets on 3D Conductive Networks for Efficient Hydrogen Evolution.

Molybdenum diselenide (MoSe2 ) has emerged as a promising electrocatalyst for hydrogen evolution reaction (HER). However, its properties are still confined due to the limited active sites and poor conductivity. Thus, it remains a great challenge to synergistically achieve structural and electronic modulations for MoSe2 -based HER catalysts because of the contradictory relationship between these two characteristics. Herein, bacterial cellulose-derived carbon nanofibers are used to assist the uniform growth of few-layered MoSe2 nanosheets, which effectively increase the active sites of MoSe2 for hydrogen atom adsorption. Meanwhile, carbonized bacterial cellulose (CBC) nanofibers provide a 3D network for electrolyte penetration into the inner space and accelerate electron transfer as well, thus leading to the dramatically increased HER activity. In acidic media, the CBC/MoSe2 hybrid catalyst exhibits fast hydrogen evolution kinetics with onset overpotential of 91 mV and Tafel slope of 55 mV dec-1 , which is much more outstanding than both bulk MoSe2 aggregates and CBC nanofibers. Furthermore, the fast HER kinetics are well supported by theoretical calculations of density-functional-theory analysis with a low activation barrier of 0.08 eV for H2 generation. Hence, this work highlights an efficient solution to develop high-performance HER catalysts by incorporating biotemplate materials, to simultaneously achieve increased active sites and conductivity.