Hydrogen Nanobubble Research Articles

Hydrogen nanobubbles and oxidative windows: Investigating how varying hydrogen concentrations influence seed germination and stress defense

The hydrogen molecule can effectively regulate plant growth and development, improving plant resistance to abiotic stresses. However, studies regarding the optimal concentration of hydrogen and the associated mechanisms of action in organisms are lacking. This study showed that the maximum germination rate of radish seeds decreased from 90 % to 50 % under the stress of cadmium ions (Cd2+), and hydrogen nanobubble (NB) water significantly alleviated the stress effect of Cd2+ on radish seed germination. A hydrogen concentration of 0.8 ppm had the best effect, reducing Cd2+ accumulation in radish seeds by 63.23 % and increasing the maximum germination rate from 50 % to 65 %. At concentrations exceeding 1.2 ppm, the beneficial effect of hydrogen was weakened or even reversed. Consequently, we integrated the concept of the oxidative window into a REDOX balance model and demonstrated that an appropriate hydrogen concentration can effectively maintain the REDOX state within organisms. Transcriptome sequencing analysis revealed that hydrogen NB water modulated Cd2+ absorption and accumulation in seeds by regulating cell wall components, alleviating oxidative stress through oxidoreductase activity, and enhancing nutrient synthesis and metabolism. This collectively alleviated the inhibitory effect of Cd2+ on seed germination. This study is helpful for further understanding the effect of hydrogen concentration on the REDOX balance of seed germination, providing a theoretical basis for selecting hydrogen concentration to improve its effectiveness in agricultural fields.

EVALUATING THE SAFETY AND THERAPEUTIC EFFICACY OF INTRAVENOUS HYDROGEN NANOBUBBLE INFUSIONS IN A HYPERCHOLESTEROLEMIC RAT MODEL

Hydrogen has emerged as a promising candidate due to its antioxidant properties and potential to modulate electron flow, enhancing mitochondrial energy metabolism and reducing oxidative stress. In this study, hypercholesterolemia male Wistar rats were utilized to investigate the safety and efficacy of intravenous hydrogen nanobubble solution (HNB). The study assessed serum lipid levels, complete blood count, and organ health following HNB administration compared to positive (simvastatin) and negative controls. Bayesian statistics were used to validate the findings. The administration of HNB did not adversely affect the immediate survival of the rats on a high fat diet (HFD), whereas simvastatin significantly reduced survival rates. It showed a dose dependent immunomodulatory effect, reducing white blood cell, lymphocyte, and monocyte counts. It also influenced erythropoiesis, as indicated by increased red blood cell counts and hemoglobin levels. A significant elevation in platelet counts was observed, suggesting potential effects on platelet production or lifespan. The study also noted changes in liver enzyme levels, with HNB indicating potential hepatoprotective effects. Furthermore, HNB treatment decrease in mean fat droplet count, suggesting a mitigation of diet induced hepatic steatosis. The findings suggest that HNB may serve as a protective agent against the deleterious effects of a high-fat diet, offering immunomodulatory and hepatoprotective benefits. This study provides a foundation for considering HNB as a potential therapeutic intervention for hypercholesterolemia and warrants further investigation into the long-term impacts of nanobubble treatment on diet induced pathologies. The consistency of results across traditional statistical significance and Bayesian evidence strengthens the validity of the observed treatment-specific effects.

Enhancing tomato fruit antioxidant potential through hydrogen nanobubble irrigation.

Eating fruits and vegetables loaded with natural antioxidants can boost human health considerably and help fight off diseases linked to oxidative stress. Hydrogen has unique antioxidant effects. However, its low-solubility and fast-diffusion has limited its applications in agriculture. Integration of hydrogen with nanobubble technology could address such problems. However, the physiological adaptation and response mechanism of crops to hydrogen nanobubbles is still poorly understood. Antioxidant concentrations of lycopene, ascorbic acid, flavonoids, and resveratrol in hydrogen nanobubble water drip-irrigated tomato fruits increased by 16.3-264.8% and 2.2-19.8%, respectively, compared to underground water and oxygen nanobubble water. Transcriptomic and metabolomic analyses were combined to investigate the regulatory mechanisms that differed from the controls. Comprehensive multi-omics analysis revealed differences in the abundances of genes responsible for hormonal control, hydrogenase genes, and necessary synthetic metabolites of antioxidants, which helped to clarify the observed improvements in antioxidants. This is the first case of hydrogen nanobubble water irrigation increasing numerous natural antioxidant parts in fruits. Considering the characteristics of hydrogen and the application of the nanobubble technology in agriculture, the findings of the present study could facilitate the understanding of the potential effects of hydrogen on biological processes and the mechanisms of action on plant growth and development.

Advantages of hydrogen nanobubble-rich concrete in workability and mechanical properties

This study investigates the potential benefits of using the 150 nm level Hydrogen Nanobubble Water (HNBW) in cement concrete. Given the significant greenhouse gas emissions associated with the cement and concrete industry, enhancing building materials performance and environmental friendliness becomes crucial. In this work, experiments were conducted to evaluate the various properties of this particular concrete formulation such as hydration heat, compressive strength, slump, air content, water absorption, electrical resistivity, rapid chloride permeability, and SEM. The results of the analysis showed that the HNBW improved the workability of the concrete by 50%. The HNBW improved the mechanical properties and durability of the concrete, resulting in an increase in compressive strength of 18.03% at 3 days and over 6% at 7 and 28 days. It reduces water absorption while improving electrical resistivity and chloride permeability resistance. Additionally, SEM imaging confirms that HNBW contributes to a more compact structure with pore and micro-crack size, thereby improving the overall performance of the concrete. Therefore, hydrogen nanobubbles, as a nanomaterial, exhibit favorable effects in meeting the demands of concrete.

Hydrogen Fertilization with Hydrogen Nanobubble Water Improves Yield and Quality of Cherry Tomatoes Compared to the Conventional Fertilizers

Although hydrogen gas (H2)-treated soil improves crop biomass, this approach appears difficult for field application due to the flammability of H2 gas. In this report, we investigated whether and how H2 applied in hydrogen nanobubble water (HNW) improves the yield and quality of cherry tomato (Lycopersicon esculentum var. cerasiforme) with and without fertilizers. Two-year-long field trials showed that compared to corresponding controls, HNW without and with fertilizers improved the cherry tomato yield per plant by 39.7% and 26.5% in 2021 (Shanghai), respectively, and by 39.4% and 28.2% in 2023 (Nanjing), respectively. Compared to surface water (SW), HNW increased the soil available nitrogen (N), phosphorus (P), and potassium (K) consumption regardless of fertilizer application, which may be attributed to the increased NPK transport-related genes in roots (LeAMT2, LePT2, LePT5, and SlHKT1,1). Furthermore, HNW-irrigated cherry tomatoes displayed a higher sugar–acid ratio (8.6%) and lycopene content (22.3%) than SW-irrigated plants without fertilizers. Importantly, the beneficial effects of HNW without fertilizers on the yield per plant (9.1%), sugar–acid ratio (31.1%), and volatiles (20.0%) and lycopene contents (54.3%) were stronger than those achieved using fertilizers alone. In short, this study clearly indicated that HNW-supplied H2 not only exhibited a fertilization effect on enhancing the tomato yield, but also improved the fruit’s quality with a lower carbon footprint.

Molecular hydrogen-based irrigation extends strawberry shelf life by improving the synthesis of cell wall components in fruit

Strawberries (Fragaria × ananassa Duch.) are highly perishable due to their soft texture, and easily decay during transportation and storage. Our previous report showed that molecular hydrogen-based irrigation in the form of hydrogen nanobubble water (HNW) could obviously improve flavor and consumer preferences of strawberry fruit at the harvesting stage. This study further investigated whether this approach could influence the shelf life of strawberry. During storage for 15 d at 4 ℃, HNW delayed the degradation in the quality of strawberry fruit, evaluated by alteration in sensory attributes (including aroma, luster, color, shape, and general evaluation), weight loss, contents of vitamin C, soluble sugar, and titratable acidity, and sugar/acid ratio. The higher levels of lignin, cellulose, and hemicellulose were observed. Compared to conventional surface water (control) irrigation, the firmness of fruit was increased by HNW irrigation at the harvest stage, and progressively maintained during the storage period. Molecular evidence revealed that before the harvesting period, the transcripts of cinnamyl CoA reductase (CCR) and cinnamyl alcohol dehydrogenase (CAD), as well as cellulose synthase 1/4/6 (CesF1/4/6), the representative genes for the synthesis of lignin, cellulose, and hemicellulose, were induced by HNW irrigation. These changes were positively matched with the increased lignin, cellulose, and hemicellulose contents at the harvesting period. Overall, the extended shelf life of strawberries achieved by molecular hydrogen-based irrigation might be due to the improvement in lignin, cellulose, and hemicellulose accumulation. Therefore, this study demonstrated the effectiveness of HNW irrigation for retarding the decay of harvested strawberries.

Hydrogen Nanobubble Water: A Good Assistant for Improving the Water Environment and Agricultural Production.

Hydrogen nanobubble water (HNW) is an emerging technique in the field of environment and agriculture that is attracting more attention due to its eminent characteristic. HNW exhibits a higher solution stagnation rate with a longer existence in water than molecular hydrogen, which ensures its practical usage. In this Viewpoint, the properties and applications of HNW are discussed. HNW, acting as an antioxidant, effectively eliminates reactive oxygen species and counteracts Cu and Cd stress; HNW also increases crop growth, enhances crops quality, and improves transportation and storage processes. On the basis of the advantages of HNW, we recommend focusing on the potential functions of HNW and broadening its wider applications in environment and agriculture.

Transient Adsorption Behavior of Single Fluorophores on an Electrode-Supported Nanobubble.

Here we report the use of a Langmuir isotherm model to analyze and better understand the dynamic adsorption and desorption behavior of single fluorophore molecules at the surface of a hydrogen nanobubble supported on an indium tin oxide (ITO) electrode. Three rhodamine dyes, rhodamine 110 (R110, positively charged), rhodamine 6G (R6G, positively charged), and sulforhodamine G (SRG, negatively charged) were chosen for this study. The use of the Langmuir isotherm model allows us to determine the equilibrium constant and the rate constants for the adsorption and desorption processes. Of the three fluorophores used in this study, SRG was found to have the greatest equilibrium constant. No significant potential dependence was observed on the adsorption characteristics, which suggests the nanobubble size, geometry, and surface properties are relatively constant within the range of potentials used in this study. Our results suggest that the use of the Langmuir isotherm model is a valid and useful means for probing and better understanding the unique adsorption behavior of fluorophores at surface-supported nanobubbles.

Nucleation behavior and kinetics of single hydrogen nanobubble in ionic liquid system

Bubbles generated on the electrode surface have been considered one of important factors limiting the efficiency of hydrogen evolution reaction (HER). However, the bubble formation behaviors have not been clearly defined, especially nanobubbles in ionic liquid system. In this work, single H2 nanobubbles generation characters are well investigated using platinum nanoelectrodes in ionic liquid (IL) during HER. The crucial factors (i.e., critical condition, geometry, and nucleation rapid of the H2 nanobubbles) are quantitatively conducted from the voltammograms. The results reveal that the H2 nanobubbles have a small contact angle (from 152° to 160°) and large bubble height (0.5–1.1 nm), which are favorable for subsequent detachment from nanoelectrode surface. Moreover, higher nucleation energy (7.5–15.3 kT) indicates that IL can suppress bubble formation. This work has gained a fundamental insight into the dynamic formation behaviors of H2 nanobubble in IL, which can guide us to study H2 bubbles in the HER influenced by various factors.

Molecular Hydrogen: The Postharvest Use in Fruits, Vegetables and the Floriculture Industry

Molecular hydrogen (H2) has been found to have significant effects in a range of organisms, from plants to humans. In the biomedical arena it has been found to have positive effects for neurodegenerative disease and even for treatment of COVID-19. In plants H2 has been found to improve seed germination, foliar growth, and crops: effects being most pronounced under stress conditions. It has also been found that treatment with H2 can improve the postharvest preservation of fruits, vegetables and flowers. Therefore, H2-based treatments may be useful for the storage and transport of food products. H2 can be delivered in a range of manners, from the use of the gas to creating H2-enriched solutions, such as hydrogen-rich water (HRW) or hydrogen nanobubble water (HNW). The exact action of H2 at a biochemical level has yet to be established. Despite this, H2 appears to be safe. Treatments of food with H2 would leave no harmful residues, and H2 itself is safe to use, as exemplified by its biomedical use. With H2 production and transport being developed for other industries, H2 is likely to become cheaper and its use for postharvest maintenance of food may be beneficial to explore further.

Molecular Hydrogen Improves Rice Storage Quality via Alleviating Lipid Deterioration and Maintaining Nutritional Values.

Improvement of the storage quality of rice is a critical challenge for the scientific community. This study assesses the effects of the irrigation with hydrogen nanobubble water (HNW) on the storage quality of rice (Oryza sativa ‘Huruan1212’). Compared with ditch water control, after one year of storage at 25 °C and 70% RH, the HNW-irrigated rice had higher contents of essential amino acids, especially lysine. Importantly, the generation of off-flavors in the stored rice was significantly decreased, which was confirmed by the lower levels of volatile substances, including pentanal, hexanal, heptanal, octanal, 1-octen-3-ol, and 2-heptanone. The subsequent results showed that the HNW-irrigated rice not only retained lower levels of free fatty acid values, but also had increased antioxidant capacity and decreased lipoxygenase activity and transcripts, thus resulting in decreased lipid peroxidation. This study opens a new window for the practical application of HNW irrigation in the production and subsequent storage of crops.

Preharvest application of hydrogen nanobubble water enhances strawberry flavor and consumer preferences

The improvement of fruit flavor is a challenge for producers and breeders. This study investigated the effects and mechanisms of preharvest hydrogen nanobubble water (HNW) application on the flavor of cultivated strawberry (Fragaria × ananassa ‘Benihoppe’). Compared with surface water, HNW enhanced the volatile profiles, sugar-acid ratio, and sensory attributes (e.g., aroma, flavor, and overall liking) with/without fertilizer application. Meanwhile, flavor components such as esters (e.g., ethyl hexanoate), acids (e.g., hexanoic acid), and soluble sugars (including glucose, fructose, and sucrose) significantly contributed to increased strawberry flavor achieved with HNW. Importantly, HNW may alleviate the negative effects of fertilizers on strawberry fruit aroma. Further study elucidated that the aroma-related genes (including FaLOX, FaADH, FaAAT, FaQR, FaOMT, and FaNES1) were involved in the accumulation of specific volatiles after HNW treatment. This study provided evidence that the practical application of H2 can improve horticultural product quality at a lower carbon cost.

Dynamic processes of hybrid nanostructured Au particles/nanobubbles in a quasi-2D system by in-situ liquid cell TEM

Recently hybrid structure of hydrogen nanobubble (HNB) and gold nanoparticles (GNP) have attracted a great deal of interest in many potential applications including ultrasound contrast agent, cancer therapy and drug delivery. For the first time, here we reported interaction of high energy electron beam with sodium citrate catalyzes a highly stable hybrid super structure (HNB ∈ Au) where sub-nanometer sized GNPs are decorated on the HNB surface. The formation mechanism of HNB ∈ Au has been in-depth studied in this work. This electron radiation technique is the easiest method for the large-scale production of environmentally benign sub-nanometer sized GNP and HNB at room temperature. We have successfully demonstrated the HNB can serve as a substrate or a template for attracting Au nano-clusters onto its surface by in-situ transmission electron microscopy in liquid environment. The kinetics of multiple coalescence process of merging ultra-small GNP and HNB has been analyzed with Mehl-Avrami-Kolmogorov (JMAK) scheme. It suggests that the growth modes for HNB and GNP in the formation process of HNB ∈ Au are 2D and 3D, respectively. Here we have also calculated the momentum transferred to the GNP from the incident electrons and surrounding liquid molecules. It indicates that the incident electrons can trigger the GNP sliding on HNB surface at relatively high dose rate.

Molecular Hydrogen Increases Quantitative and Qualitative Traits of Rice Grain in Field Trials.

How to use environmentally friendly technology to enhance rice field and grain quality is a challenge for the scientific community. Here, we showed that the application of molecular hydrogen in the form of hydrogen nanobubble water could increase the length, width, and thickness of brown/rough rice and white rice, as well as 1000-grain weight, compared to the irrigation with ditch water. The above results were well matched with the transcriptional profiles of representative genes related to high yield, including up-regulation of heterotrimeric G protein β-subunit gene (RGB1) for cellular proliferation, Grain size 5 (GS5) for grain width, Small grain 1 (SMG1) for grain length and width, Grain weight 8 (GW8) for grain width and weight, and down-regulation of negatively correlated gene Grain size 3 (GS3) for grain length. Meanwhile, although total starch content in white rice is not altered by HNW, the content of amylose was decreased by 31.6%, which was parallel to the changes in the transcripts of the amylose metabolism genes. In particular, cadmium accumulation in white rice was significantly reduced, reaching 52% of the control group. This phenomenon was correlated well with the differential expression of transporter genes responsible for Cd entering plants, including down-regulated Natural resistance-associated macrophage protein (Nramp5), Heavy metal transporting ATPase (HMA2 and HMA3), and Iron-regulated transporters (IRT1), and for decreasing Cd accumulation in grain, including down-regulated Low cadmium (LCD). This study clearly showed that the application of molecular hydrogen might be used as an effective approach to increase field and grain quality of rice.

Hydrogen Nanobubble Water Delays Petal Senescence and Prolongs the Vase Life of Cut Carnation (Dianthus caryophyllus L.) Flowers.

The short vase life of cut flowers limits their commercial value. To ameliorate this practical problem, this study investigated the effect of hydrogen nanobubble water (HNW) on delaying senescence of cut carnation flowers (Dianthus caryophyllus L.). It was observed that HNW had properties of higher concentration and residence time for the dissolved hydrogen gas in comparison with conventional hydrogen-rich water (HRW). Meanwhile, application of 5% HNW significantly prolonged the vase life of cut carnation flowers compared with distilled water, other doses of HNW (including 1%, 10%, and 50%), and 10% HRW, which corresponded with the alleviation of fresh weight and water content loss, increased electrolyte leakage, oxidative damage, and cell death in petals. Further study showed that the increasing trend with respect to the activities of nucleases (including DNase and RNase) and protease during vase life period was inhibited by 5% HNW. The results indicated that HNW delayed petal senescence of cut carnation flowers through reducing reactive oxygen species accumulation and initial activities of senescence-associated enzymes. These findings may provide a basic framework for the application of HNW for postharvest preservation of agricultural products.

Formation of a Hydrogen Radical in Hydrogen Nanobubble Water and Its Effect on Copper Toxicity in Chlorella

Formation of a Hydrogen Radical in Hydrogen Nanobubble Water and Its Effect on Copper Toxicity in <i>Chlorella</i>

Mechanical Strength and Hydration Characteristics of Cement Mixture with Highly Concentrated Hydrogen Nanobubble Water.

In this study, highly concentrated hydrogen nanobubble water was utilized as the blending water for cement mortar to improve its compressive and flexural strengths. Highly concentrated nanobubbles can be obtained through osmosis. This concentration was maintained by sustaining the osmotic time. The mortar specimens were cured for 28 days, in which the nanobubble concentration was increased. This improved their flexural strength by 2.25–13.48% and compressive strength by 6.41–11.22%, as compared to those afforded by plain water. The nanobubbles were densified at high concentrations, which caused a decrease in their diameter. This increased the probability of collisions with the cement particles and accelerated the hydration and pozzolanic reactions, which facilitated an increase in the strength of cement. Thermogravimetric analysis and scanning electron microscopy were used to confirm the development of calcium silicate hydrate (C-S-H) and hydration products with an increase in the nanobubble concentration. Quantitative analysis of the hydration products and the degree of hydration were calculated by mineralogical analysis.

Effect of Hydrogen Nanobubbles on the Mechanical Strength and Watertightness of Cement Mixtures.

This study analyzed the effects of applying highly concentrated hydrogen nanobubble water (HNBW) on the workability, durability, watertightness, and microstructure of cement mixtures. The number of hydrogen nanobubbles was concentrated twofold to a more stable state using osmosis. The compressive strength of the cement mortar for each curing day was improved by about 3.7–15.79%, compared to the specimen that used general water, when two concentrations of HNBW were used as the mixing water. The results of mercury intrusion porosimetry and a scanning electron microscope analysis of the cement paste showed that the pore volume of the specimen decreased by about 4.38–10.26%, thereby improving the watertightness when high-concentration HNBW was used. The improvement in strength and watertightness is a result of the reduction of the microbubbles’ particle size, and the increase in the zeta potential and surface tension, which activated the hydration reaction of the cement and accelerated the pozzolanic reaction.

Free radical degradation in aqueous solution by blowing hydrogen and carbon dioxide nanobubbles

The main findings are the hydroxyl radical scavenging and the superoxide anion diminishing by mixing the carbon dioxide (CO2) nanobubbles after hydrogen nanobubble blowing in water and alcohol aqueous solution. The nanobubbles produce the hydroxyl radical by ultrasonic waves, changing the pH and catalyst and so on, while the nanobubble is very reactive to scavenge free radicals. In this research especially hydrogen (4% H2 in argon) and CO2 nanobubbles have been blown into hydrogen peroxide (H2O2) added pure water, ethanol, and ethylene glycol aqueous solution through a porous ceramic sparger from the gas cylinder. The aqueous solutions with H2O2 are irradiated by ultraviolet (UV) light and the produced hydroxyl radical amount is measured with spin trapping reagent and electron spin resonance (ESR). The CO2 nanobubble blowing extremely has reduced the hydroxyl radical in water, ethanol, and ethylene glycol aqueous solution. On the other hand, when H2 nanobubbles are brown after CO2 nanobubble blowing, the hydroxyl radical amount has increased. For the disinfection test, the increase of hydroxyl radicals is useful to reduce the bacteria by the observation in the agar medium. Next, when the superoxide anion solution is mixed with nanobubble containing water, ethanol, and ethylene glycol aqueous solution, H2 nanobubble has reduced the superoxide anion slightly. The water containing both CO2 and H2 nanobubble reduces the superoxide anion. The less than 20% ethanol and the 30% ethylene glycol aqueous solution containing CO2 nanobubbles generated after H2 nanobubble blowing can diminish the superoxide anion much more. While the H2 nanobubble blowing after CO2 nanobubble blowing scavenges the superoxide anion slightly. The experimental results have been considered using a chemical reaction formula.

Alleviation of copper toxicity in Daphnia magna by hydrogen nanobubble water

As a novel antioxidant, hydrogen water has been widely used to alleviate oxidative stress in plants as well as in the medical field. However, the function of hydrogen water in environmental toxicology remains unknown. In this study, combining nanobubbles (NBs) and hydrogen water, we investigate the effect and mechanism of hydrogen NB water on copper induced acute toxicity to water fleas (Daphnia magna). The 24-h lethal Cu concentrations at which 50 % of the population die were 84 μg/L in hydrogen NB water and 45 μg/L in control water, confirming that hydrogen NB water effectively alleviated acute Cu toxicity in D. magna. The results were consistent with a significant reduction of Cu uptake and decrease of Cu accumulation in D. magna. As confirmed in fluorescence spectrophotometry and high-content screening system analysis, the hydrogen NB water also significantly reduced the oxidative damage and improved Cu tolerance in D. magna. From the results, it can be inferred that hydrogen NB water alleviates Cu stress in D. magna by depressing Cu bioaccumulation and reducing oxidative stress. The results provide basic data of hydrogen NB water for environmental toxicologists, and also a reference for the application of hydrogen NB water in the environment.