Effective degradation of various bacterial toxins using ozone ultrafine bubble water.

Infectious and foodborne diseases pose significant global threats, with devastating consequences in low- and middle-income countries. Ozone, derived from atmospheric oxygen, exerts antimicrobial effects against various microorganisms, and degrades fungal toxins, which were initially recognized in the healthcare and food industries. However, highly concentrated ozone gas can be detrimental to human health. In addition, ozonated water is unstable and has a short half-life. Therefore, ultrafine-bubble technology is expected to overcome these issues. Ultrafine bubbles, which are nanoscale entitles that exist in water for considerable durations, have previously demonstrated bactericidal effects against various bacterial species, including antibiotic-resistant strains. This present study investigated the effects of ozone ultrafine bubble water (OUFBW) on various bacterial toxins. This study revealed that OUFBW treatment abolished the toxicity of pneumolysin, a pneumococcal pore-forming toxin, and leukotoxin, a toxin that causes leukocyte injury. Silver staining confirmed the degradation of pneumolysin, leukotoxin, and staphylococcal enterotoxin A, which are potent gastrointestinal toxins, following OUFB treatment. In addition, OUFBW treatment significantly inhibited NF-κB activation by Pam3CSK4, a synthetic triacylated lipopeptide that activates Toll-like receptor 2. Additionally, OUFBW exerted bactericidal activity against Staphylococcus aureus, including an antibiotic-resistant strain, without displaying significant toxicity toward human neutrophils or erythrocytes. These results suggest that OUFBW not only sterilizes bacteria but also degrades bacterial toxins.

Effects of Ozone Disc Nucleolysis in Management of Herniated Lumbar Intervertebral Disc: A Retrospective Single-Center Study of 149 Patients.

BACKGROUND Lower back pain is a common problem in the general population. Medical treatment is the first choice for patients without severe pain and major motor weakness. If patients do not benefit from conservative treatment, minimally invasive treatment is recommended. Ozone nucleolysis has recently been used to reduce pain and inflammation in herniated discs and other spinal conditions. This retrospective study from a single center aimed to evaluate the effects of ozone disc nucleolysis in the management of 149 patients with herniated lumbar intervertebral discs from 2022 to 2024. MATERIAL AND METHODS Between 2022 and 2024, intradiscal ozone nucleolysis was performed under operating room C-arm scopy in 149 patients who received medical treatment and physical therapy without surgical indication but did not benefit, and the results were evaluated retrospectively. Visual Analog Scale (VAS) scores and Oswestry Disability Index (ODI) scores were recorded before the procedure, and at 1 month, 3 months, 6 months, and 1 year. RESULTS The study enrolled 149 patients, comprising 61 males and 88 females, with an overall mean age of 43.9±4.7 years. The procedure was performed as 1 level in 138 patients and 2 levels in 11 patients. Among patients who underwent procedures based on lumbar MRI findings, 15 involved the L3-L4 intervertebral disc, 3 involved both the L3-L4 and L4-L5 discs, 90 involved the L4-L5 disc, and 31 involved the L5-S1 disc. Post-procedure VAS scores were significantly different at 1 month and 6 months (P<0.05). Post-procedure ODI scores were also significantly different at 1 month and 6 months. CONCLUSIONS Due to its low complication rate and effectiveness in treating lumbar disc herniation, ozone chemonucleolysis should be considered for use in patients who do not have a surgical indication or do not accept surgical intervention and did not benefit from medical treatment and physical therapy.

Dilute acid-assisted microbubbles-mediated ozonolysis of Eucheuma denticulatum phycocolloid for biobased L-lactic acid production.

Biobased L-lactic acid (L-LA) appeals to industries; however, existing technologies are plagued by limited productivity and high energy consumption. This study established an integrated process for producing macroalgae-based L-LA from Eucheuma denticulatum phycocolloid (EDP). Dilute acid-assisted microbubbles-mediated ozonolysis (DAMMO) was selected for the ozonolysis of EDP to optimize D-galactose recovery. Through single-factor optimization of DAMMO treatment, a maximum D-galactose recovery efficiency (59.10 %) was achieved using 0.15 M H2SO4 at 80 °C for 75 min. Fermentation with 3 % (w/v) mixed microbial cells (Bacillus coagulans ATCC 7050 and Lactobacillus acidophilus-14) and fermented residues achieved a 97.67 % L-LA yield. Additionally, this culture approach was further evaluated in repeated-batch fermentation and showed an average L-LA yield of 93.30 %, providing a feasible concept for macroalgae-based L-LA production.

Anti-Inflammatory Activity of No-Ozone Cold Plasma in Porphyromonas gingivalis Lipopolysaccharide-Induced Periodontitis Rats.

Periodontitis is an inflammatory disease caused by Porphyromonas gingivalis (P. gingivalis) in the oral cavity. This periodontal disease causes damage to the periodontal ligament and alveolar bone and can cause tooth loss, but there is no definite treatment yet. In this study, we investigated the possibility of using no-ozone cold plasma to safely treat periodontitis in the oral cavity. First, human gingival fibroblasts (HGFs) were treated with P. gingivalis-derived lipopolysaccharide (PG-LPS) to induce an inflammatory response, and then the anti-inflammatory effect of NCP was examined, and a study was conducted to identify the mechanism of action. Additionally, the anti-inflammatory effect of NCP was verified in rats that developed an inflammatory response similar to periodontitis. When NCP was applied to PG-LPS-treated HGFs, the activities of inflammatory proteins and cytokines were effectively inhibited. It was confirmed that the process of denaturing the medium by charged particles of NCP is essential for the anti-inflammatory effect of NCP. Also, it was confirmed that repeated treatment of periodontitis rats with NCP effectively reduced the inflammatory cells and osteoclast activity. As a result, this study suggests that NCP can be directly helpful in the treatment of periodontitis in the future.

A new biostimulant derived from soybean by-products enhances plant tolerance to abiotic stress triggered by ozone.

BACKGROUND: Tropospheric ozone is an air pollutant that causes negative effects on vegetation, leading to significant losses in crop productivity. It is generated by chemical reactions in the presence of sunlight between primary pollutants resulting from human activity, such as nitrogen oxides and volatile organic compounds. Due to the constantly increasing emission of ozone precursors, together with the influence of a warming climate on ozone levels, crop losses may be aggravated in the future. Therefore, the search for solutions to mitigate these losses becomes a priority. Ozone-induced abiotic stress is mainly due to reactive oxygen species generated by the spontaneous decomposition of ozone once it reaches the apoplast. In this regard, compounds with antioxidant activity offer a viable option to alleviate ozone-induced damage. Using enzymatic technology, we have developed a process that enables the production of an extract with biostimulant properties from okara, an industrial soybean byproduct. The biostimulant, named as OEE (Okara Enzymatic Extract), is water-soluble and is enriched in bioactive compounds present in okara, such as isoflavones. Additionally, it contains a significant fraction of protein hydrolysates contributing to its functional effect. Given its antioxidant capacity, we aimed to investigate whether OEE could alleviate ozone-induced damage in plants. For that, pepper plants (Capsicum annuum) exposed to ozone were treated with a foliar application of OEE. RESULTS: OEE mitigated ozone-induced damage, as evidenced by the net photosynthetic rate, electron transport rate, effective quantum yield of PSII, and delayed fluorescence. This protection was confirmed by the level of expression of genes associated with photosystem II. The beneficial effect was primarily due to its antioxidant activity, as evidenced by the lipid peroxidation rate measured through malondialdehyde content. Additionally, OEE triggered a mild oxidative response, indicated by increased activities of antioxidant enzymes in leaves (catalase, superoxide dismutase, and guaiacol peroxidase) and the oxidative stress index, providing further protection against ozone-induced stress. CONCLUSIONS: The present results support that OEE protects plants from ozone exposure. Taking into consideration that the promotion of plant resistance against abiotic damage is an important goal of biostimulants, we assume that its use as a new biostimulant could be considered.

Ozone enhances the efficacy of radiation therapy in esophageal cancer.

Radioresistance is increasingly developed in esophageal cancer. Increasing radiation sensitivity can reduce the mortality of esophageal cancer. To investigate the effect and mechanism of ozone on the radiotherapy sensitization of esophageal carcinoma. KYSE150 cells were xenografted subcutaneously into nude mice and irradiated with 8 Gy radiation according to different subgroups (sham, radiation, ozone and radiation+ozone group (n = 10 per group)). Half of the mice were used to determine the body weight, tumor size and tumor weight. Half of the mice were used to collect peripheral blood. The serum was centrifuged to detect circulating cell-free DNA (cf-DNA), interleukin-6 (IL-6), interferon-γ (IFN-γ), myeloperoxidase (MPO)-DNA complexes, tumor necrosis factor-α (TNF-α), matrix metalloproteinase-9 (MMP-9) and hypoxia-inducible factor-1α (HIF-1α) using commercial kits. The levels of phosphorylation AMP-activated protein kinase (p-AMPK) and scavenger receptor-A (SR-A) were measured by immunocytochemistry and Western blotting in the tumor tissues of mice. Ozone alone or combined with radiation therapy significantly reduced the body weight, tumor volume and tumor weight of esophageal cancer compared to the sham group. The ELISA results showed that the levels of cf-DNA, IFN-γ, MPO-DNA complexes, TNF-α, IL-6, HIF-1α and MMP-9 in the peripheral blood of mice treated with ozone combined with radiation were significantly lower compared with the radiation group. Ozone, synergistically with radiation, significantly increased the protein expression of p-AMPK and SR-A. Ozone may increase the radiosensitivity of esophageal cancer by inhibiting neutrophil extracellular traps.

Efficacy of ozonated olive oil against peri-implant microbes isolated from peri-implantitis.

This study aimed to investigate the antibacterial and antimicrobial activity of ozone gel against oral biofilms grown on titanium dental implant discs. The experiment used medical grade five titanium discs on which peri-implant isolated biofilms were grown. The experimental groups were control, Streptococcus mutans (S. mutans) and Granulicatella adiacens (G. adiacens), (n = 6). The oral microbes grown on titanium discs were exposed to ozone gel for 3 minutes and the antibacterial activity was assessed by turbidity test and adherence test for the antibiofilm activity test. Bacterial morphology and confluence were investigated by scanning electron microscopy (SEM), (n=3). Two bacterial species were identified from the peri-implant sample, S. mutans and G. adiacens. The results showed that adding ozone to the bacterial biofilm on titanium dental implants did not exhibit significant antibacterial activity against S. mutans. Moreover, there was no significant difference in antibiofilm activity between control and treatment groups. However, significant antibacterial and antibiofilm effect was exhibited by ozone gel against G. adiacens. Ozonated olive oil can be considered as a potential antimicrobial agent for disinfecting dental implant surfaces and treating peri-implantitis.

Ozone and peroxone disinfection of Toxocara canis eggs in water.

Water pollution in developing countries continues to be a major health problem due to various anthropological activities that contribute to the spread of many parasitic diseases, including those caused by helminths. The aim of this study is to explore the ability of ozone and peroxone to disinfect drinking water contaminated samples with Toxocara canis eggs. The oxidants used were ozone and ozone-hydrogen peroxide combination. The treatment of Toxocara canis eggs was carried out in a 50 ml reactor with an operating volume of 10 ml. The pH conditions (5, 7 and 10) were varied for each treatment. The treatment effect was calculated by counting eggs and examining the condition of the larvae larval condition (whole, broken and hatched larvae) using an optical microscope. The experiment was carried out by exposing the eggs for 60 and 120 minutes to ozone and peroxone. The best results were obtained for helminths treated with the ozone/hydrogen peroxide combination at pH 10, with an inactivation of 79.2%. The synergistic effect of ozone combined with hydrogen peroxide allows higher helminth egg inactivation rates, demonstrating that advanced oxidation processes are a real alternative to apply in the inactivation of Toxocara canis eggs. The results obtained in this study show that the ozone and peroxone treatment could be a useful disinfection process to destroy or inactivate Toxocara canis eggs in processes commonly applied in water treatment.

Evaluation of Remineralizing Capacity of Tricalcium Phosphate, Nano-Hydroxyapatite and Ozone Remineralizing Agents on the Artificial Carious Lesion.

BACKGROUND: Dental caries is a dynamic process. By using therapeutic agents, early, noncavitated lesions and caries limited to the enamel can be stopped or even remineralized. For the remineralization of the initial carious lesion, many nonfluoridated remineralizing agents were investigated. OBJECTIVES: An observational study to assess the remineralizing efficacy of tricalcium phosphate (TCP), nano-hydroxyapatite (nHAp) and ozone remineralizing agents on the artificial carious lesion. METHODOLOGY: In this observational research, the artificial carious lesion was produced on extracted 40 premolar teeth. Later, remineralizing agents (Group A: nHAp, Group B: TCP, Group C: Ozone remineralizing agents, Group D: Control group (Deionized water) were used to remineralize demineralized teeth. Utilizing the Vickers Hardness Number, the level of demineralization and remineralization was assessed. Later these readings were statistically assessed using the Tukey's HSD (honestly significant difference) and ANOVA tests in SPSS version 21.0. The P value was set at 0.05 or less. RESULTS: After demineralization, there was a decrease in enamel microhardness values, with 32% in Group A, 26% in Group B, 22% in Group C, and 21% in Group D, respectively. From the baseline to demineralization, there was a statistically significant decrease in microhardness across all groups. After remineralization, Groups A, B, and C experienced an increase in microhardness while Group D experienced no changes. This showed that Group A had the highest remineralization percentage, followed by Group B and Group C. CONCLUSION: nHAp and TCP had the greater remineralizing ability, which can be used to manage initial carious lesions.

Gases and gas-releasing materials for the treatment of chronic diabetic wounds.

Chronic non-healing wounds are a common consequence of skin ulceration in diabetic patients, with severe cases such as diabetic foot even leading to amputations. The interplay between pathological factors like hypoxia-ischemia, chronic inflammation, bacterial infection, impaired angiogenesis, and accumulation of advanced glycosylation end products (AGEs), resulting from the dysregulation of the immune microenvironment caused by hyperglycemia, establishes an unending cycle that hampers wound healing. However, there remains a dearth of sufficient and effective approaches to break this vicious cycle within the complex immune microenvironment. Consequently, numerous scholars have directed their research efforts towards addressing chronic diabetic wound repair. In recent years, gases including Oxygen (O2), Nitric oxide (NO), Hydrogen (H2), Hydrogen sulfide (H2S), Ozone (O3), Carbon monoxide (CO) and Nitrous oxide (N2O), along with gas-releasing materials associated with them have emerged as promising therapeutic solutions due to their ability to regulate angiogenesis, intracellular oxygenation levels, exhibit antibacterial and anti-inflammatory effects while effectively minimizing drug residue-induced damage and circumventing drug resistance issues. In this review, we discuss the latest advances in the mechanisms of action and treatment of these gases and related gas-releasing materials in diabetic wound repair. We hope that this review can provide different ideas for the future design and application of gas therapy for chronic diabetic wounds.

Use of Ozone as a Substrate Treatment for the Control of Trichoderma in the Production of Pleurotus ostreatus.

Pleurotus ostreatus is one of the most widely cultivated species in the world. It can be produced in many lignocellulosic substrates after carrying out a treatment to eliminate competing microorganisms. The most commonly used is pasteurization by steam or by immersion in hot water. The aim of this work is to evaluate if ozone can be employed as treatment for decontamination of the substrate used for the production of the edible mushroom P. ostreatus to control of green mold Trichoderma. Wheat straw was employed as a substrate. We used two different methodologies: bubbling ozone into a tank with water and the substrate, and injecting ozone into a closed tank with the substrate inside. Ten treatments were carried out including two treatments with inoculation by a spray of conidia of Trichoderma. The effect of ozone on the conidia was also evaluated. We found that the treatment of the substrate with ozone in immersed water resulted more effective (lower growth of Trichoderma) than injecting ozone into a closed tank. Anyway, we found that the contaminant fungi could grow on the substrate in both treatments with ozone. We observed that although ozone affected the conidia when it was bubbled into water, some of them still managed to survive and could germinate 72 h later. P. ostreatus could grow and produce fruiting bodies on a substrate that was previously treated with ozone and yields were not affected. Based on the results obtained, we conclude that ozone may not be an effective agent to control Trichoderma in highly contaminated substrates, at least in the experimental conditions that we used, for the production of P. ostreatus.

The effect of intra-articular ozone injection combined with home-based exercise on pain and function in daily living activities of patients with mild to moderate knee osteoarthritis, a randomized double-blinded controlled clinical trial.

BACKGROUND: Knee osteoarthritis is the most common arthritis. Various treatments such as analgesics, exercise therapy, and surgery in high-grade OA have been shown to reduce pain and improve patients' function; however, determining the optimal treatment remains a challenge. Ozone therapy is one of the injection techniques used for symptom relief in these patients. Therefore, this study aimed to evaluate the effect of ozone injection in mild to moderate knee osteoarthritis. METHODS: Thirty-three patients with grade II-III knee osteoarthritis based on the Kellgren-Lawrence classification were involved in the study, by block randomisation. Totally 42 knees were included. All patients received exercise therapy, 500 mg of acetaminophen tablets (up to 2 g per day as needed), and healthy nutrition. In a double-blinded method, the intervention group received Ozone injections, but the control group received placebo injections. Functional tests, including timed-up-and-go and 6-min walk tests, were assessed at baseline and immediately after the 6-week intervention. In addition, the pain was measured by VAS score, and stiffness and activity of daily living (ADL) were evaluated by KOOS questionnaire before and after a 6-week intervention and then one and six months afterwards. FINDINGS: Improvements in pain and KOOS scores were seen in both groups in the 6th week of injections (p < 0.05), with significant differences between groups. However, the effects on pain and KOOS scores disappeared in the 1st and 6th months of follow-ups in the control group. Nevertheless, the effects persisted in the intervention group compared to the baseline and control group, which means that in the mentioned time points intervention group showed significant improvement compared to the control group (p < 0.05). In addition, functional tests showed significant differences between the two groups in the 6th week of injections (p < 0.001). INTERPRETATION: Ozone injection is a non-surgical treatment for mild to moderate knee osteoarthritis that could decrease pain and improve function and ADL of patients in the short to mid-term (3-6 months), so it seems that adding Ozone injection to the routine exercise therapy in management of patients with knee OA could improve outcomes.

Leaf water relations determine the trade-off between ozone resistance and stomatal functionality in urban tree species.

Urban trees possess different capacities to mitigate ozone (O3) pollution through stomatal uptake. Stomatal closure protects trees from oxidative damage but limits their growth. To date, it is unclear how plant hydraulic function affect stomatal behaviour and determine O3 resistance. We assessed gas exchange and hydraulic traits in three subtropical urban tree species, Celtis sinensis, Quercus acutissima, and Q. nuttallii, under nonfiltered ambient air (NF) and elevated O3 (NF60). NF60 decreased photosynthetic rate (An) and stomatal conductance (gs) only in Q. acutissima and Q. nuttallii. Maintained An in C. sinensis suggested high O3 resistance and was attributed to higher leaf capacitance at the full turgor. However, this species exhibited a reduced stomatal sensitivity to vapour pressure deficit and an increased minimal gs under NF60. Such stomatal dysfunction did not decrease intrinsic water use efficiency (WUE) due to a tight coupling of An and gs. Conversely, Q. acutissima and Q. nuttallii showed maintained stomatal sensitivity and increased WUE, primarily correlated with gs and leaf water relations, including relative water content and osmotic potential at turgor loss point. Our findings highlight a trade-off between O3 resistance and stomatal functionality, with efficient stomatal control reducing the risk of hydraulic failure under combined stresses.

Divergent responses of ascorbate and glutathione pools in ozone-sensitive and ozone-tolerant wheat cultivars under elevated ozone and carbon dioxide interaction.

Crop plants face complex tropospheric ozone (O3) stress, emphasizing the need for a food security-focused management strategy. While research extensively explores O3's harmful effects, this study delves into the combined impacts of O3 and CO2. This study investigates the contrasting responses of O3-sensitive (PBW-550) and O3-resistant (HUW-55) wheat cultivars, towards elevated ozone (eO3) and elevated carbon dioxide (eCO2), both individually and in combination. The output of the present study confirms the positive effect of eCO2 on wheat cultivars exposed to eO3 stress, with more prominent effects on O3-sensitive cultivar PBW-550, as compared to the O3-resistant HUW-55. The differential response of the two wheat cultivars can be attributed to the mechanistic variations in the enzyme activities of the Halliwell-Asada pathway (AsA-GSH cycle) and the ascorbate and glutathione pool. The results indicate that eCO2 was unable to uplift the regeneration of the glutathione pool in HUW-55, however, PBW-550 responded well, under similar eO3 conditions. The study's findings, highlighting mechanistic variations in antioxidants, show a more positive yield response in PBW-550 compared to HUW-55 under ECO treatment. This insight can inform agricultural strategies, emphasizing the use of O3-sensitive cultivars for sustained productivity in future conditions with high O3 and CO2 concentrations.

Evaluation of the restorative effect of ozone and chitosan-hyaluronic acid with and without mesenchymal stem cells on wound healing in rats.

This study evaluated the effect of ozone, chitosan-hyaluronic (Cs-HA) acid and mesenchymal stem cells (MSCs) on wound healing in rats. A total of 64 rats were randomly divided into four groups: control, ozone, Cs-HA + ozone and Cs-HA + ozone + MSCs. A 5 mm full-thickness wound was created on the back of each rat. The wound area was measured macroscopically on days 3, 5, 9 and 14. Tissue sections were prepared for histopathological evaluation of inflammation, collagen arrangement, neovascularization and epithelial tissue rearrangement. Macroscopic assessment showed differences in wound area on days 5, 9 and 14. Histopathological examination showed that the Cs-HA + ozone + MSCs and Cs-HA + ozone groups had significantly higher vascularization on day 3 compared to the ozone-treated and control groups. All treatment groups had significantly better collagen arrangement than the control group. On day 5, no significant difference was observed between different groups. On day 9, the inflammation level in the Cs-HA + ozone + MSCs group was significantly lower than in the other groups. All treatment groups had significantly better vascularization compared to the control group. On day 14, the rate of inflammation was significantly lower in the treatment groups than in the control group. Significantly higher collagen arrangement levels were observed in the Cs-HA + ozone and Cs-HA + ozone + MSCs groups compared to the control and ozone groups. All treatment groups had significantly better epithelial tissue rearrangement than the control group. Overall, the results of this study indicated that treatment with ozone, Cs-HA acid, Cs-HA and MSCs accelerated wound healing in rats. The effect of using Cs-HA acid with mesenchymal cells was better than the other types of treatment. Larger clinical trials are needed to assess these factors for improving chronic wound treatment.

Short-time ozone treatment promotes protease-mediated destruction of B cell allergen epitopes by altering the structural characteristics of whey protein.

A novel processing method combining short-time ozone pretreatment with hydrolysis has been developed to reduce whey protein allergenicity. The results showed that ozone treatment altered the whey protein spatial structure, initially increasing the surface hydrophobicity index, and then decreasing due to polymer formation as the time increased. Under the optimized conditions of alkaline protease-mediated hydrolysis, a 10-second pre-exposure to ozone significantly promoted the reduction in the IgE binding capacity of whey protein without compromising the hydrolysis efficiency. Compared with whey protein, the degranulation of KU812 cells stimulated by this hydrolysate decreased by 20.54%, 17.99%, and 22.80% for IL-6, ß-hexosaminidase, and histamine, respectively. In vitro simulated gastrointestinal digestion confirmed increased digestibility and reduced allergenicity. Peptidomics identification revealed that short-time ozonation exposed allergen epitopes, allowing alkaline protease to target these epitopes more effectively, particularly those associated with α-lactalbumin. These findings suggest the promising application of this processing method in mitigating the allergenicity of whey protein.

Effects of systemic ozone administration on the fresh extraction sockets healing: a histomorphometric and immunohistochemical study in rats.

OBJECTIVE: Studies have highlighted numerous benefits of ozone therapy in the field of medicine and dentistry, including its antimicrobial efficacy against various pathogenic microorganisms, its ability to modulate the immune system effectively, reduce inflammation, prevent hypoxia, and support tissue regeneration. However, its effects on dental extraction healing remain to be elucidated. .Therefore, this study aimed to evaluate the effects of systemically administered ozone (O3) at different doses in the healing of dental extraction sockets in rats. METHODOLOGY: To this end, 72 Wistar rats were randomly divided into four groups after extraction of the right upper central incisor: Group C - control, no systemic treatment; Group OZ0.3 - animals received a single dose of 0.3 mg/kg O3; Group OZ0.7 - a single dose of 0.7 mg/kg O3; and Group OZ1.0 - a single dose of 1.0 mg/kg O3, intraperitoneally. In total, six animals from each group were euthanized at 7, 14, and 21 days after the commencement of treatment. Bone samples were harvested and further analyzed by descriptive histology, histomorphometry, and immunohistochemistry for osteocalcin (OCN) and tartrate-resistant acid phosphatase (TRAP) protein expression. RESULTS: All applied doses of O3 were shown to increase the percentage of bone tissue (PBT) after 21 days compared to group C. After 14 days, the OZ0.7 and OZ1.0 groups showed significantly higher PBT when compared to group C. The OZ1.0 group presented the most beneficial results regarding PBT among groups, which denotes a dose-dependent response. OCN immunostaining was higher in all groups at 21 days. However, after seven and 14 days, the OZ1.0 group showed a significant increase in OCN immunostaining compared to C group. No differences in TRAP+ osteoclasts were found between groups and time points. CONCLUSION: Therefore, O3 therapy at higher doses might be beneficial for bone repair of the alveolar socket following tooth extraction.

Extraction of homogeneous lignin oligomers by ozonation of Miscanthus giganteus and vine shoots in a pilot scale reactor.

Lignin, a complex phenolic polymer crucial for plant structure, is mostly used as fuel but it can be harnessed for environmentally friendly applications. This article explores ozonation as a green method for lignin extraction from lignocellulosic biomass, aiming to uncover the benefits of the extracted lignin. A pilot-scale ozonation reactor was employed to extract lignin from Miscanthus giganteus (a grass variety) and vine shoots (a woody biomass). The study examined the lignin extraction and modification of the fractions and identified the generation of phenolic and organic acids. About 48 % of lignin was successfully extracted from both biomass types. Phenolic monomers were produced, vine shoots yielding fewer monomers than Miscanthus giganteus. Ozonation generated homogeneous lignin oligomers, although their molecular weight decreased during ozonation, with vine shoot oligomers exhibiting greater resistance to ozone. Extracted fractions were stable at 200 °C, despite the low molecular weight, outlining the potential of these phenolic fractions.

Systematic investigation and modeling prediction of virus inactivation by ozone in wastewater: Decoupling the matrix effects.

Water disinfection is undoubtedly regarded as a critical step in ensuring the water safety for human consumption, and ozone is widely used as a highly effective disinfectant for the control of pathogenic microorganisms in water. Although the diminished ozone efficiencies in complex water matrices have been widely reported, the specific extent to which individual components of matrix act on the virus inactivation by ozone remains unclear, and effective methodologies to predict the comprehensive effects of various factors are needed. In this study, the decoupled impact of the intricate water matrix on the ozone inactivation of viruses was systematically investigated and assessed from a simulative perspective. The concept of "equivalent ozone depletion rate constant" (k') was introduced to quantify the influence of different species, and a kinetic model was developed based on the k' values for simulating the ozone inactivation processes in complex matrix. The mechanisms through which diverse species influenced the ozone inactivation effectiveness were identified: 1) competition effects (k' = 105∼107 M-1s-1), including organic matters and reductive ions (SO32-, NO2-, and I-), which were the most influential species inhibiting the virus inactivation; 2) shielding effects (k' = 103∼104 M-1s-1), including Ca2+, Mg2+, and kaolin; 3) insignificant effects (k' = 0∼1 M-1s-1), including Cl-, SO42-, NO3-, NH4+, and Br-; 4) promotion effects (k' = ∼-103 M-1s-1), including CO32- and HCO3-. Prediction of ozone disinfection efficiency and evaluation of species contribution under complex aquatic matrices were successfully realized utilizing the model. The systematic understanding and methodologies developed in this research provide a reliable framework for predicting ozone inactivation efficiency under complex matrix, and a potential tool for accurate disinfectant dosage determination and interfering factors control in actual wastewater treatment processes.

Mechanism of antibiotic resistance spread during sub-lethal ozonation of antibiotic-resistant bacteria with different resistance targets.

The increase and spread of antibiotic-resistant bacteria (ARB) in aquatic environments and the dissemination of antibiotic resistance genes (ARGs) greatly impact environmental and human health. It is necessary to understand the mechanism of action of ARB and ARGs to formulate measures to solve this problem. This study aimed to determine the mechanism of antibiotic resistance spread during sub-lethal ozonation of ARB with different antibiotic resistance targets, including proteins, cell walls, and cell membranes. ARB conjugation and transformation frequencies increased after exposure to 0-1.0 mg/L ozone for 10 min. During sub-lethal ozonation, compared with control groups not stimulated by ozone, the conjugative transfer frequencies of E. coli DH5α (CTX), E. coli DH5α (MCR), and E. coli DH5α (GEN) increased by 1.35-2.02, 1.13-1.58, and 1.32-2.12 times, respectively; the transformation frequencies of E. coli DH5α (MCR) and E. coli DH5α (GEN) increased by 1.49-3.02 and 1.45-1.92 times, respectively. When target inhibitors were added, the conjugative transfer frequencies of antibiotics targeting cell wall and membrane synthesis decreased 0.59-0.75 and 0.43-0.76 times, respectively, while that for those targeting protein synthesis increased by 1-1.38 times. After inhibitor addition, the transformation frequencies of bacteria resistant to antibiotics targeting the cell membrane and proteins decreased by 0.76-0.89 and 0.69-0.78 times, respectively. Cell morphology, cell membrane permeability, reactive oxygen species, and antioxidant enzymes changed with different ozone concentrations. Expression of most genes related to regulating different antibiotic resistance targets was up-regulated when bacteria were exposed to sub-lethal ozonation, further confirming the target genes playing a crucial role in the inactivation of different target bacteria. These results will help guide the careful utilization of ozonation for bacterial inactivation, providing more detailed reference information for ozonation oxidation treatment of ARB and ARGs in aquatic environments.