N-doped Cu2O with the tunable Cu0 and Cu+ sites for selective CO2 electrochemical reduction to ethylene.

The electrochemical carbon dioxide reduction reaction (CO2RR) to high value-added fuels or chemicals driven by the renewable energy is promising to alleviate global warming. However, the selective CO2 reduction to C2 products remains challenge. Cu-based catalyst with the specific Cu0 and Cu+ sites is important to generate C2 products. This work used nitrogen (N) to tune amounts of Cu0 and Cu+ sites in Cu2O catalysts and improve C2-product conversion. The controllable Cu0/Cu+ ratio of Cu2O catalyst from 0.16 to 15.19 was achieved by adjusting the N doping amount using NH3/Ar plasma treatment. The major theme of this work was clarifying a volcano curve of the ethylene Faraday efficiency as a function of the Cu0/Cu+ ratio. The optimal Cu0/Cu+ ratio was determined as 0.43 for selective electroreduction CO2 to ethylene. X-ray spectroscopy and density functional theory (DFT) calculations were employed to elucidate that the strong interaction between N and Cu increased the binding energy of NCu bond and stabilize Cu+, resulting in a 92.3% reduction in the potential energy change for *CO-*CO dimerization. This study is inspiring in designing high performance electrocatalysts for CO2 conversion.

Nitrogen uptake, grain yield, and oil concentration of dwarf castor beans under nitrogen rates and inoculation of rhizobacteria in grasses-legumes rotation.

Introduction: Plant growth-promoting bacteria (PGPB) have been primarily studied for atmospheric nitrogen (N) fixation but they also have the capacity to improve nutrition and yield of crop plants. Methods: Therefore, the objective of this research was to investigate the effects of inoculation with PGPB in association with different N rates on N uptake, grain yield, and oil concentration of dwarf castor beans in succession to legumes and grasses in Ilha Solteira, Brazil. The treatments consisted of N rates (0 to 180 kg ha-1 of N) and inoculation with three plant growth-promoting bacteria (Azospirillum brasiliense, Bacillus subtilis, and Pseudomonas fluorescens, applied by leaf) and a control with no-inoculation. Results: The grain and oil yields of castor beans were increased by 20 and 40% at a rate of 103 kg ha-1 of N in succession to grasses as compared to without N application. In addition, the grain yield of castor bean after legumes was increased by 28, 64, and 40% with estimated rates of 97, 113, and 92 kg ha-1 of N in combination with inoculations of A. brasilense, B. subtilis, and P. fluorescens as compared to without N application, respectively. Shoot, grain, and total N uptake were improved with foliar inoculation of A. brasilense, B. subtilis, and P. fluorescens at the N rates of 45, 90, and 135 kg ha-1, respectively. Discussion and conclusions: Topdressing of N at the rate of 103 kg ha-1 and foliar inoculation in succession to grasses and 180 kg ha-1 of N without the effect of foliar inoculation in succession to legumes are recommended for higher grain and oil yield of castor beans. Foliar inoculations with A. brasilense, B. subtilis, and P. fluorescens increased grain yield under reduced use of N fertilizer by 44, 37, and 49% in dwarf castor cultivation in succession to legumes, potentially contributing to sustainable agriculture.

Nitrogen-containing heterocyclic drug products approved by the FDA in 2023: Synthesis and biological activity.

This article profiles 13 newly approved nitrogen-containing heterocyclic drugs by the U.S. Food and Drug Administration (FDA) in 2023. These drugs target a variety of therapeutic areas including proteinuria in patients with IgA nephropathy, migraine in adults, Rett syndrome, PI3Kδ syndrome, vasomotor symptoms, alopecia areata, acute myeloid leukemia, postpartum depression, myelofibrosis, and various cancer and tumor types. The molecular structures of these approved drugs feature common aromatic heterocyclic compounds such as pyrrole, imidazole, pyrazole, isoxazole, pyridine, and pyrimidine, as well as aliphatic heterocyclic compounds like caprolactam, piperazine, and piperidine. Some compounds also contain multiple heteroatoms like 1,2,4-thiadiazole and 1,2,4-triazole. The article provides a comprehensive overview of the bioactivity spectrum, medicinal chemistry discovery, and synthetic methods for each compound.

Co-composting of tail vegetable with flue-cured tobacco leaves: analysis of nitrogen transformation and estimation as a seed germination agent for halophyte.

Resource utilization of tail vegetables has raised increasing concerns in the modern agriculture. However, the effect and related mechanisms of flue-cured tobacco leaves on the product quality, phytotoxicity and bacterially-mediated nitrogen (N) transformation process of tail vegetable composting were poorly understood. Amendments of high-dosed (5% and 10% w/w) tobacco leaves into the compost accelerated the heating process, prolonged the time of thermophilic stage, increased the peak temperature, thereby improving maturity and shortening composting duration. The tobacco leaf amendments at the 10% (w/w) increased the N conservation (TN and NH4-N content) of compost, due to the supply of N-containing nutrient and promotion of organic matter degradation by tobacco leaves. Besides, tobacco leaf amendments promoted the seed germination and root development of wild soybean, exhibiting the feasibility of composting product for promoting the growth of salt-tolerant plants, but no dose-dependent effect was found for tobacco leaf amendments. Addition of high dosed (5% and 10% w/w) tobacco leaves shifted the bacterial community towards lignocellulosic and N-fixing bacteria, contributing to increasing the compost maturity and N retention. PICRUSt 2 functional prediction revealed that N-related bacterial metabolism (i.e., hydroxylamine oxidation and denitrifying process) was enhanced in the tobacco leaf treatments, which contributed to N retention and elevated nutrient quality of composting. To the best knowledge, this was the first study to explore the effect of tobacco waste additives on the nutrient transformation and halophyte growth promotion of organic waste composting. These findings will deepen the understanding of microbially-mediated N transformation and composting processes involving flue-cured tobacco leaves.

Nitrogen-doped carbon quantum dots (NCQDs) detected to mercury ions in food monitoring.

Using 2,3-diaminopyridine and citric acid as precursors, blue fluorescent nitrogen-doped carbon quantum dots (NCQDs) with a narrow size distribution (∼7.2 nm) were prepared and applied in the following assay for mercury ion detection at a weight ratio of 2,3-diaminopyridine:citric acid = 1:1 (0.2 g: 0.2 g, 20 mL for H2O), 220 °C, and 10 h. NCQDs was characterized by TEM, FT-IR, XPS, UV-Vis and EDS, and the prepared NCQDs display excitation-independent behavior due to less surface defects and uniform size. The optimal excitation and emission wavelengths of the NCQDs were 380 nm and 430 nm, respectively. Interestingly, the fluorescence of the NCQDs could be rapidly and selectively quenched by Hg2+ within 9 min at room temperature without further modification. Under optimal conditions, the limit of detection (LOD) was measured to be at the nanomolar level (42.4 nmol/L) with a linear range of 0-5.0 µmol/L, and fluorescence analysis of NCQDs was successfully used for the qualitative and quantitative analysis of mercury ions in food samples. Furthermore, our results revealed that fluorescence quenching occurred under the common fluences of the inner filter effect, and the static quenching effect was authenticated in the process in which Hg2+ coordinates with the NCQDs to form nonfluorescent complexes.

Nitrogen-containing bisphosphonate induces enhancement of OPG expression and inhibition of RANKL expression via inhibition of farnesyl pyrophosphate synthase to inhibit the osteogenic differentiation and calcification in vascular smooth muscle cells.

BACKGROUND: Nitrogen-containing bisphosphonate(N-BP)had been found to inhibit the osteogenic differentiation and calcification in vascular smooth muscle cells (VSMCs), but the mechanism is not clear. We intend to verify that N-BP induces enhancement of OPG expression and inhibition of RANKL expression via inhibition of farnesyl pyrophosphate synthase(FPPS) to inhibit the osteogenic differentiation and calcification in VSMCs. METHODS: ß-glycerophosphate (ß-GP) was used to induce the osteogenic differentiation and calcification in VSMCs. VSMCs were treated with N-BP or pretreated with downstream products of farnesyl pyrophosphate synthase(FPPS) in mevalonate pathway, such as farnesol (FOH) or geranylgeraniol (GGOH). Alizarin red S staining and determination of calcium content were used to detect calcium deposition.Western Blotting were used to detect expressions of proteins(OPG and RANKL ) and osteogenic marker proteins (Runx2 and OPN). RESULTS: ß-GP induced the osteogenic differentiation and calcification in VSMCs, increased RANKL protein expression and had no significant effect on OPG protein expression. With the treatment of N-BP, the expression of OPG protein was increased and expression of RANKL protein was decreased in VSMCs undergoing osteogenic differentiation and calcification. In addition, N-BP reduced the osteogenic marker proteins (Runx2 and OPN) expression and calcium deposition in VSMCs undergoing osteogenic differentiation and calcification. These effects of N-BP on the osteogenic differentiation and calcification in VSMCs were concentration-dependent, which could be reversed by the downstream products of FPPS, such as FOH or GGOH. CONCLUSION: N-BP increases OPG expression and decreases RANKL expression via inhibition of FPPS to inhibit the osteogenic differentiation and calcification in VSMCs.

Role of SbNRT1.1B in cadmium accumulation is attributed to nitrate uptake and glutathione-dependent phytochelatins biosynthesis.

Phytoremediation of cadmium (Cd)-polluted soil by using sweet sorghum displays a tremendous potential as it is a fast-growing, high biomass and Cd tolerant energy plant. Previous study has demonstrated SbNRT1.1B expression change is in accordance with enhanced Cd accumulation by external nitrate supply in sweet sorghum. Nevertheless, underlying mechanism of SbNRT1.1B response to Cd stress is still elusive. SbNRT1.1B exhibited a positive response to Cd stress in sweet sorghum. Overexpressing SbNRT1.1B increased primary root length, shoot fresh weight, nitrate and chlorophyll concentrations compared with Col-0 under Cd stress, while complementary SbNRT1.1B rescued these decreased values in mutant chl1-5. Cd concentrations in overexpressing SbNRT1.1B, complementary SbNRT1.1B and Col-0 lines were 3.2-4.1, 2.5-3.1 and 1.2-2.1 folds of that in chl1-5. Consistent with Cd concentrations, non-protein thiol (NPT), reduced glutathione (GSH) and phytochelatins (PCs) concentrations as well as the related genes expression levels showed the same trends under Cd stress. GSH biosynthesis inhibitor failed to reverse the patterns of GSH-dependent PCs concentrations changes in different lines, suggesting that SbNRT1.1B plays an upstream role in GSH-dependent PCs biosynthesis under Cd treatment. Altogether, SbNRT1.1B enhances nitrate concentrations contributing to increased chlorophyll concentrations and GSH-dependent PCs metabolites biosynthesis, thereby improving growth and Cd concentrations in plants.

Microplastics from polyvinyl chloride agricultural plastic films do not change nitrogenous gas emission but enhance denitrification potential.

The effects of microplastics (MPs) from agricultural plastic films on soil nitrogen transformation, especially denitrification, are still obscure. Here, using a robotized flow-through system, we incubated vegetable upland soil cores for 66 days with MPs from PE mulching film (F-PE) and PVC greenhouse film (F-PVC) and directly quantified the emissions of nitrogenous gases from denitrification under oxic conditions, as well as the denitrification potential under anoxic conditions. The impact of MPs on soil nitrogen transformation was largely determined by the concentration of the additive phthalate esters (PAEs) containing in the MPs. The F-PE MPs with low level of PAEs (about 0.006 %) had no significant effect on soil mineral nitrogen content and nitrogenous gas emissions under oxic conditions. In contrast, the F-PVC MPs with high levels of PAEs (about 11 %) reduced soil nitrate content under oxic conditions, probably owing to promoted microbial assimilation of nitrogen, as the emissions of denitrification products (N2, NO, and N2O) was not affected. However, the F-PVC MPs significantly enhanced the denitrification potential of the soil due to the increased abundance of denitrifiers under anoxic conditions. These findings highlight the disturbance of MPs from agricultural films, particularly the additive PAEs on nitrogen transformation in soil ecosystems.

Investigating the effect of hydraulic residence time, artificial aeration and plants presence on different constructed wetland designs treating oil industry effluent.

Constructed Wetlands (CW) have gained popularity over the last decades due to their cost-effectiveness, easy and simple operation and environmental compatibility in wastewater treatment. This ecological engineering technology appears particularly ideal for low-income regions. In this study, three widely used CW types (horizontal flow, vertical flow, and hybrid CW) were constructed and evaluated for their effectiveness in removing various pollution parameters (BOD5, COD, TSS, NH4-N, NO3-N, and TP) from an industrial effluent. Different configurations were tested such as CW type, hydraulic residence time, plants presence, and artificial aeration. Results showed that the hybrid CW configuration (i.e., vertical flow CW followed by horizontal subsurface flow CW) achieved the highest removal rates of all pollutants, i.e., more than 90% of BOD5, COD, TSS, and NH4-N. The single horizontal flow and vertical flow CW designs showed variations in the removal of NO3-N and TP (less than 30%), which were significantly improved (50% and 70%, respectively) by using the hybrid CW system. Artificial aeration significantly improves the performance of the CW system, especially for ammonia nitrogen and organic matter removal, while plants presence is also beneficial in the treatment performance. An 8-days HRT seems to be adequate for high removal rates in passive CW designs, though in aerated wetlands a lower HRT of 4 days seems sufficient. These findings suggest that the hybrid CW system could be a promising option for efficient wastewater treatment in developing regions.

Enhancing collaboration of anammox with heterotrophic microbes mediated selectively by iron of different valences: Activities balance, metabolic mechanism, and functional genes regulation.

The partial denitrification/anammox (PD/A) process is receiving increasing attention due to its cost-effectiveness advantages. However, effective strategies to alleviate organic matter inhibition and promote anammox activity have been proven to be a big challenge. This study investigated the effects of three types of iron (nano zero-valent iron (nZVI), Fe(II), and Fe(III)) on the PD/A process. It is worth noting that nZVI of 5-50 mg/L and Fe(III) of 5-120 mg/L promoted both PD and anammox activity. Long-term intermittent addition of nZVI (50 mg/L) resulted in a nitrogen removal efficiency of 98.2% in the mixotrophic PD/A system driven by iron and organic matter. The contribution of anammox for nitrogen removal reached as high as 93.8%. The organic carbon demand decreased due to the external electron donor provided by nZVI for PD. Multiple Fe-N metabolic pathways, primarily involving ammonia oxidation by Fe(III) and nitrate reduction by nZVI, play a crucial role in facilitating nitrogen transformation. Conversely, the direct addition of 30-120 mg/L Fe (II) resulted in a significant decrease in pH to below 5.0 and severe inhibition of PD and anammox activity. Following prolonged operation in the presence of nZVI, it was demonstrated that there is an enhancing effect on robust nitrite production for anammox. This was accompanied by a remarkable up-regulation of genes encoding nitrate reductase and iron-transporting proteins dominated by Thauera. Overall, this study has provided an efficient approach for advanced nitrogen removal through organic- and iron-driven anammox processes.

Temperature-modulated morphological changes in MIL-88B(Fe)-derived iron-based materials triggering generation of the peroxymonosulfate nonradical pathway to degrade carbamazepine: The key role of iron nanoparticles and CN.

Temperature modulation of the synthesis process of MOF-derived composites is not well understood for changes in the peroxymonosulfate catalytic domain. This study synthesized a carbon-based nitrogen-doped (MN@C) MOF-derived composite catalyst derived from MIL-88B(Fe) (Materials Institute Lavoisier) by modulating temperature changes and calcination. Combined with density-functional theory calculations (DFT) analyses showed that changes in iron nanoparticles (FeNP) and CN content caused the alterations of the degradation pathways. MN@C-9 exhibited outstanding activation performance (100 % carbamazepine (CBZ) removal within 10 min). The system maintained efficient operation in different aqueous environments and a wide pH range and demonstrated efficient removal of many pollutants typical of pharmaceuticals and personal care products (PPCPs). After comprehensively analyzing the results of liquid chromatography mass spectrometry (LC-MS) and toxicity prediction, the possible degradation pathways were reasonably speculated, and the toxicity of the byproducts was greatly reduced. This study provides a potential and efficient catalyst preparation strategy for water purification.

Does liquid nitrogen recycled autograft for treatment of bone sarcoma impact local recurrence rate? A systematic review.

The gold standard treatment for primary bone sarcomas has been surgical resection with wide margins. However, there is no consensus regarding an optimal method for limb salvage reconstruction. In 2005, a technique for recycling resected bone after intraoperative treatment with liquid nitrogen was described. This technique has been reported to have a spectrum of advantages; nonetheless, acceptance for routine use has been limited, primarily for fear of local recurrence. A systematic search of the literature using PubMed and Google Scholar was performed. Full-text articles published between 2008 and 2023 were included if the study presented sufficient information regarding patients with a diagnosis of a primary bone sarcoma of the limbs or pelvis who had undergone reconstruction with liquid nitrogen recycled autografts. Sixteen studies that included 286 patients met criteria for analyses. Local recurrence occurred in 25 patients (8.7 %) during the first 4 years following limb salvage reconstruction using recycled autografts for treatment of primary bone sarcomas, which compares favorably to the 15-30 % local recurrence rates reported for patients undergoing limb salvage reconstruction using artificial implants. Systematic synthesis of the current evidence regarding local recurrence rates following use of the liquid nitrogen recycled autograft technique for limb salvage reconstruction after bone sarcoma resection suggests a favorable comparison to other limb salvage reconstruction options. As such, this technique warrants further consideration as a viable option for indicated patients based on relative advantages regarding costs, availability, and biologic and surgical reconstruction benefits.

Mitigating soil nitrification and greenhouse gas emissions in non-paddy cropping systems by micro-molar hydrogen peroxide.

Non-paddy cropping systems play a significant role in food production. However, excessive nitrogen loss from non-paddy soils through nitrate leaching and ammonia volatilization poses a significant challenge to environmental sustainability. In this study, microcosm and field-scale experiments were conducted to explore the potential for using hydrogen peroxide (H2O2) to mitigate nitrogen loss and greenhouse gas emissions, aiming at filling gaps in knowledge regarding the underlying biochemical mechanisms. The results show that input of micromolar H2O2 from either artificial addition or natural rainwater into soils in the presence of magnetite (Fe3O4) could trigger Fenton-like reaction, which inhibited microbially mediated nitrification of soil-borne ammonium but did not affect the growth of the test crop plant (water spinach). In the absence of Fe3O4, input of rainwater-borne H2O2 into non-paddy soils caused reduction in the emissions of nitrous oxide (N2O) and carbon dioxide (CO2). There was a trend showing that the degree of reduction in N2O and CO2 fluxes increased with increasing concentration of rainwater-borne H2O2. It was likely that microbially mediated reduction of iron oxides took place during rainfall events, providing Fe(II) that is needed for reaction with rainwater-borne H2O2, triggering Fenton-like reaction to inhibit the soil microbes that mediate production of N2O and CO2 in the soils. The findings obtained from this study have implications for developing strategies to manage soil­nitrogen to minimize its environmental impacts.

Uncovering the spatial characteristics of global net anthropogenic nitrogen input at high resolution and across 1.42 million lake basins.

Global Net Anthropogenic Nitrogen Input (NANI) at high resolution is crucial for assessing the impact of human activities on aquatic environments. Insufficient global high-resolution data sources and methods have hindered the effective examination of the global characteristics and driving forces of NANI. This study presents a general framework for calculating global NANI, providing estimates at a 5-arc-minute resolution and over 1.42 million lake basins in 2015. The results highlight the region near the Tropic of Cancer as a concentration area for high NANI and an inflection point for latitude-based accumulation variation. It also emphasizes the uneven distribution of NANI among continents, with Asia and Africa having the highest proportions, yet their high and low values are notably lower than those of Europe and South America. A similar pattern is observed in global lakes, where Asia has the smallest quantity and volume, but the highest NANI intensity. In contrast, North America and Europe have larger quantities and volumes but the lowest NANI intensity. The global distribution characteristics reveal a clustering pattern in high and low values, with 1.25 % of the area having a sum of NANI exceeding 20 %. The uncertainty analysis regarding model parameters indicates that continents with the highest NANI do not always exhibit the highest uncertainty. These results bridge the gap between global nitrogen sustainable management and anthropogenic nitrogen input. They support research on spatiotemporal changes and controlling factors of global river nutrient loads, as well as the impact of climatic factors on basin nitrogen loss and its variability.

Biochemical and Antioxidant Characteristics of Chlorococcum oleofaciens (Chlorophyceae, Chlorophyta) under Various Cultivation Conditions.

The functional state of enrichment cultures of the Chlorophycean strain Chlorococcum oleofaciens CAMU MZ-Ch4 under various cultivation conditions was studied. Experiments with different aeration conditions, cultivation durations, and nitrogen and phosphorus concentrations in the medium were carried out to evaluate the growth dynamics of the strain and its biochemical characteristics. The contents of chlorophylls, carotenoids, proteins, lipids, retinol, α-tocopherol, ascorbic acid, phenolic compounds, lipid peroxidation products, antioxidant enzymes (glutathione peroxidase, catalase, superoxide dismutase), and succinate dehydrogenase activity were measured. The lipid content on the fully supplemented Bold's basal medium increased to 381.03 mg g-1 dry weight at the late stationary growth phase. This value is 1.3-2.8 times higher than in other experiments. The use of aeration was associated with an increased content of proteins at 283.56 mg g-1 and of carotenoids at 2.12 mg g-1. Also, cultures at the early stationary growth phase with aeration showed the ability to accumulate phenolic compounds and ascorbic acid in amounts up to 0.32 mg g-1 and 0.19 mg g-1. The 74-day-old cultures had the highest contents of retinol (0.16 mg g-1) and α-tocopherol (0.68 mg g-1). Growth in nitrogen- and phosphorus-depleted media increased catalase and superoxide dismutase activity. A comprehensive analysis of all data showed that the antioxidant defence system is stress-resistant and flexible under varying aeration conditions and nitrogen and phosphorus availabilities. Thus, the strain CAMU MZ-Ch4 can be considered a potential producer of lipids, pigments, proteins, and vitamins under various culturing conditions.

Effects of Different Straw Return Modes on Soil Carbon, Nitrogen, and Greenhouse Gas Emissions in the Semiarid Maize Field.

Returning straw to the field is a crucial practice for enhancing soil quality and increasing efficient use of secondary crop products. However, maize straw has a higher carbon-to-nitrogen ratio compared to other crops. This can result in crop nitrogen loss when the straw is returned to the field. Therefore, it is crucial to explore how different methods of straw return affect maize (Zea mays L.) farmland. In this study, a field experiment was performed with three treatments (I, no straw returned, CK; II, direct straw return, SR; and III, straw returned in deep furrows, ISR) to explore the effects of the different straw return modes on soil carbon and nitrogen content and greenhouse gas emissions. The results indicated that the SR and ISR treatments increased the dissolved organic carbon (DOC) content in the topsoil (0-15 cm). Additionally, the ISR treatment boosted the contents of total nitrogen (TN), nitrate nitrogen (NO3--N), ammonium nitrogen (NH4+-N), dissolved organic nitrogen (DON), and DOC in the subsurface soil (15-30 cm) compared with CK. When it comes to greenhouse gas emissions, the ISR treatment led to an increase in CO2 emissions. However, SR and ISR reduced N2O emissions, with ISR showing a more pronounced reduction. The ISR treatment significantly increased leaf and grain biomass compared to CK and SR. The correlation analyses showed that the yield was positively correlated with soil DOC, and soil greenhouse gas emission was correlated with soil NO3--N. The ISR technology has great potential in sequestering soil organic matter, improving soil fertility, and realizing sustainable agricultural development.

Effects of cadmium stress on the growth and physiological characteristics of sweet potato.

This study evaluated the responses of sweet potatoes to Cadmium (Cd) stress through pot experiments to theoretically substantiate their comprehensive applications in Cd-polluted agricultural land. The experiments included a CK treatment and three Cd stress treatments with 3, 30, and 150 mg/kg concentrations, respectively. We analyzed specified indicators of sweet potato at different growth periods, such as the individual plant growth, photosynthesis, antioxidant capacity, and carbohydrate Cd accumulation distribution. On this basis, the characteristics of the plant carbon metabolism in response to Cd stress throughout the growth cycle were explored. The results showed that T2 and T3 treatments inhibited the vine growth, leaf area expansion, stem diameter elongation, and tuberous root growth of sweet potato; notably, T3 treatment significantly increased the number of sweet potato branches. Under Cd stress, the synthesis of chlorophyll in sweet potato was significantly suppressed, and the Rubisco activity experienced significant reductions. With the increasing Cd concentration, the function of PS II was also affected. The soluble sugar content underwent no significant change in low Cd concentration treatments. In contrast, it decreased significantly under high Cd concentrations. Additionally, the tuberous root starch content decreased significantly with the increase in Cd concentration. Throughout the plant growth, the activity levels of catalase, peroxidase, and superoxide dismutase increased significantly in T2 and T3 treatments. By comparison, the superoxide dismutase activity in T1 treatment was significantly lower than that of CK. With the increasing application of Cd, its accumulation accordingly increased in various sweet potato organs. The the highest bioconcentration factor was detected in absorbing roots, while the tuberous roots had a lower bioconcentration factor and Cd accumulation. Moreover, the transfer factor from stem to petiole was the highest of the potato organs. These results demonstrated that sweet potatoes had a high Cd tolerance and a restoration potential for Cd-contaminated farmland.

Effect of different nitrogen source and Saccharomyces cerevisiae strain on volatile sulfur compounds and their sensory effects in chardonnay wine.

Three commercial Saccharomyces cerevisiae strains with low, medium, and high H2S-producing capacity were chosen to investigate the effect of yeast assimilable nitrogen (YAN) levels and composition on volatile compounds in a chemically defined medium, specifically high, medium, and low initial YAN levels with varying proportions of DAP or sulfur-containing amino acids (cysteine and methionine). The results revealed that the initial YAN containing a larger proportion of diammonium phosphate resulted in a higher YAN consumption rate during the early stages of fermentation. The yeast strain had a greater effect on the volatiles than the YAN level and composition. Keeping the total YAN constant, a higher proportion of sulfur-containing amino acids resulted in a considerably higher production of 3-methylthiopropanol. The sensory impact of three key volatile sulfur compounds was investigated in a Chardonnay wine matrix, indicating that 3-methylthiopropanol at subthreshold or greater concentrations was effective in enhancing the cantaloupe aroma.

Differential regulation of physicochemical properties and myofibrillar protein degradation of yak meat by interactions between reactive oxygen species and reactive nitrogen species during postmortem aging.

BACKGROUND: This study aimed to explore how interactions between reactive oxygen species (ROS) and reactive nitrogen species (RNS) affect oxidative properties, nitrosative properties, and myofibrillar protein degradation during postmortem aging of yak meat. RESULTS: Yak longissimus dorsi was incubated with saline, ROS activator (H2O2)/inhibitor N-Acetyl-L-cysteine (NAC) and RNS activator S-Nitrosoglutathione (GSNO)/inhibitor L-NAME hydrochloride (L-NAME) combined treatments at 4 °C for 12, 24, 72, 120, and 168 h. The results indicated that regardless of whether RNS was activated or inhibited, activated ROS played a dominant role in myofibrillar protein degradation by oxidative modification to increase carbonyl content, disulfide bonds, surface hydrophobicity, and dimerized tyrosine while decreasing sulfhydryl content, thereby degrading nebulin, titin, troponin-t and desmin. Notably, the Warner-Bratzler shear force (WBSF) of the H2O2 + L-NAME group was the smallest, whereas that of the NAC + GSNO group was smaller than that of the NAC + L-NAME group. CONCLUSION: These findings provide new insights into meat tenderization patterns through the interaction between ROS and RNS. © 2024 Society of Chemical Industry.

Real-Time and Wireless Transmission of a Nitrogen-Doped Ti3C2Tx Wearable Gas Sensor for Efficient Detection of Food Spoilage and Ammonia Leakage.

With the rising popularity of smart homes, there is an urgent need for devices that can perform real-time online detection of ammonia (NH3) concentrations for food quality measurement. In addition, timely warning is crucial to preventing individual deaths from NH3. However, few studies can realize continuous monitoring of NH3 with high stability and subsequent application validation. Herein, we report on an integrated device equipped with a nitrogen-doped Ti3C2Tx gas sensor that shows great potential in detecting food spoilage and NH3 leakage. The nitrogen doping results in the lattice misalignment of Ti3C2Tx, subsequently realizing effective barrier height modulation and enhanced charge transfer efficiency of nitrogen-doped Ti3C2Tx. Density functional theory calculations confirm the greatly enhanced adsorption of NH3 on nitrogen-doped Ti3C2Tx. Our work can inspire the design of efficient gas sensors for real-time and wireless detection of food spoilage and NH3 leakage.