Microscopic mechanistic study of the penetration distributions for plasma reactive oxygen and nitrogen species based on sialic acid targeting on the cell membrane surface.

The ability of cold atmospheric plasmas (CAPs) to produce a wide range of active constituents while maintaining a low or even room temperature of the gas has made it a novel research area of great interest. During plasma action, cancer cell membrane surface components are susceptible to oxidative modification by reactive oxygen and nitrogen species (RONS). In this study, the process of oxidative modification of membrane surface components sialic acid by RONS was investigated based on molecular dynamics simulations, and the penetration mechanism of long-lived particles ONOOH and its homolytic products at the membrane-water interface and the effect of appropriate electric field action were studied. The results showed that cancer cells with high sialic acid expression were less stable than healthy cells. Plasma treatment may promote the ONOOH homolysis process, and its homolysis product OH free radical is more likely to adsorb near sialic acid molecules by hydrogen bonding, resulting in oxidative modification. The interaction force between OH free radical and sialic acid molecules is stronger than ONOOH, which helps to further understand the oxidative modification reaction in membrane environment. At the same time, appropriate electric field stimulation can enhance the depth of penetration of RONS to more effectively treat the pathological state of biological tissues. The study proposes the use of membrane surface sialic acid as a cancer therapeutic target and provides guidance for improving the depth of RONS penetration and maximizing the survival of healthy cells, which contributes to the further clinical translation of plasma biomedicine.

Higher Sensitivity of Rat Testes to Nano Nickel than Micro Nickel Particles: A Toxicological Evaluation.

Present investigations were undertaken to record the vulnerability of testis to nickel oxide nano and microparticles in Wistar rat with special reference to their preferred bioaccumulation, consequent generation of reactive species, reciprocal influence on testosterone synthesis, DNA damage in spermatids and histopathological changes. Suitable numbers of rats were gavaged NiONPs or NiOMPs (5 mg/kg b.w.each) for 15 and 30 days. Testes en bloc were removed and processed for the estimation of selected parameters. Results showed that rat testes could accumulate nickel in an exposure time dependent manner. Generation of malondialdehyde, a denominator of ROS, increased significantly in the testes of NiONPs treated rats. Moreover, serum testosterone values also increased in NiONPs treated rats. Higher DNA damage in sperms was also recorded. Nano and microparticles of nickel, both could induce specific dose and time dependent lesions in the testis of rat. Histopathological results revealed degeneration of germinal epithelium and spermatocytes; hypertrophy of seminiferous tubules and necrosis. SEM results also indicated specific morphological changes in cellular components of tubules. This study suggests that testis is also vulnerable to the adverse effects of NiONPs alike liver and kidney. Both micro and nanoparticles of nickel elicited differential effects in a dose and exposure time dependent manner. However, NiONPs induced greater overall toxicity than NiOMPs. The results are expected to be helpful in determining the human reproductive health risks, associated with environmental/ occupational exposure to nanoparticles of nickel.

Synergistically enhanced heterogeneous activation of dissolved oxygen for aqueous carbamazepine degradation over S(III) coupled with siderite.

The wide occurrence of emerging contaminants (ECs) was drawing more attention due to the potential hazard and threat on human and environment. Carbamazepine (CBZ) is a widely prescribed medication that has garnered considerable research interest with the exposures exceeding the environmental carrying capacity. We have established the innovative heterogeneous advanced oxidation process (AOPs) based on the activated dissolved oxygen (DO) coupled with S(III) and natural iron ore (siderite). In S(III)/O2/siderite system, we investigated the degradation efficiency, reactive species generation mechanism, and degradation pathway of CBZ. CBZ degradation and mineralization rate were 90% above and ∼15% with the reaction time of 40 minutes. The degradation of CBZ conformed to a pseudo-first-order kinetic model, with an activation energy determination of 76.36 kJ/mol. The optimal initial solution pH was the weak acid condition (pH = 4-6) for CBZ degradation. Moreover, the inhibition effects of coexisting substance including Cl-, HCO3-, and natural organic matter (NOM) on CBZ removal were observed, while the coexisted SO42- exhibited no significant influence. In addition, the reactive species generated in S(III)/O2/siderite system were predominantly identified as sulfate radical (SO4∙-) and hydroxyl radical (∙OH). The crucial intermediate complexes, Fe(III)S(IV)O3(+) and Fe(II)HS(IV)O3(+), was proposed to form in the initial stages of the reaction, which upon decomposition, yielded SO4∙- along with other reactive species. The degradation pathway of CBZ primarily involved deamination, oxidative ring-opening, hydroxylation, decarboxylation, and ketone degradation processes. This work provides the effective approach for the CBZ degradation with the mild reaction conditions and the sustainable technology for ECs treatment and control.

Secondary activation on plasma-activated water by plasma-treated cotton for restoring and enhancing disinfection effect.

Plasma-activated water (PAW) is a novel antimicrobial agent with negligible toxicity and environmental burden, holding promise as an alternative to chemical disinfectants and antibiotics. In practice, liquid disinfectants are often soaked with cotton materials before further use. Rich in reducing functional groups on the surface, cotton will inevitably react with PAW, leading to the deterioration of PAW's functions. To resolve this issue, this work proposes a new concept of "secondary activation" for retaining and enhancing PAW's bioactivity, i.e., pre-treating cotton with air plasma before soaking PAW. For the first time, we find that the PAW absorbed by raw cotton completely loses its bactericidal effect, while plasma-treated cotton (PTC) restores the disinfection capacity and prolongs its effective duration. This restoration is attributed to the absorption of plasma-generated reactive species by cotton with oxidizing and nitrifying modifications on the fiber surface. Consequently, the concentrations of aqueous species in PAW increase rather than decrease after absorption by PTC. In addition, the PTC after 28-day storage can still enable PAW to achieve a bacterial reduction of ∼3 logs. This work identifies and addresses a crucial limitation in the disinfection application of PAW and elucidates the mechanism underlying PTC production and secondary activation of PAW.

Reactive species of plasma-activated water for murine norovirus 1 inactivation.

Human norovirus (HuNoV), the leading cause of foodborne acute gastroenteritis, poses a serious threat to public health. Traditional disinfection methods lead to destructions of food properties and functions, and/or environmental contaminations. Green and efficient approaches are urgently needed to disinfect HuNoV. Plasma-activated water (PAW) containing amounts of reactive species is an emerging nonthermal and eco-friendly disinfectant towards the pathogenic microorganisms. However, the disinfection efficacy and mechanism of PAW on HuNoV has not yet been studied. Murine norovirus 1 (MNV-1) is one of the most commonly used HuNoV surrogates to evaluate the efficacy of disinfectants. In the current study, the inactivation efficacy of MNV-1 by PAW was investigated. The results demonstrated that PAW significantly inactivated MNV-1, reducing the viral titer from approximately 6 log10 TCID50/mL to non-detectable level. The decreased pH, increased oxidation-reduction potential (ORP) and conductivity of PAW were observed compared with that of deionized water. Compositional analysis revealed that hydrogen peroxide (H2O2), nitrate (NO3-) and hydroxyl radical (OH) were the functional reactive species in MNV-1 inactivation. L-histidine could scavenge most of the inactivation effect in a concentration-dependent manner. Moreover, PAW could induce damage to viral proteins. Part of MNV-1 particles was destroyed, while others were structurally intact without infectiousness. After 45 days of storage at 4 °C, PAW generated with 80 % O2 and 100 % O2 could still reduce over 4 log10 TCID50/mL of the viral titer. In addition, PAW prepared using hard water induced approximately 6 log10 TCID50/mL reduction of MNV-1. PAW treatment of MNV-1-inoculated blueberries reduced the viral titer from 3.79 log10 TCID50/mL to non-detectable level. Together, findings of the current study uncovered the crucial reactive species in PAW inactivate MNV-1 and provided a potential disinfection strategy to combat HuNoV in foods, water, and environment.

Efficient electrochemical removal of ammoniacal nitrogen from livestock wastewater: The role of the electrode material.

Wastewater from livestock farms contains high concentrations of suspended solids, organic contaminants, and nitrogen compounds, such as ammoniacal nitrogen. Discharging livestock effluents into water bodies without appropriate treatment leads to severe environmental pollution. Compared to conventional treatment methods, electrochemical oxidation exhibits higher nitrogen removal efficiencies. In the present work, the electrochemical removal of ammoniacal nitrogen from real livestock wastewater was investigated through a lab-scale reactor. Preliminary experiments were carried out to investigate the effects of different anode materials, including boron-doped diamond and iridium/ruthenium-coated titanium, on the total nitrogen removal efficiency using synthetic wastewater. Boron-doped diamond, a well-known non-active electrode, allowed to obtain 63.7 ± 1.21 % of total nitrogen degradation efficiency. However, the iridium/ruthenium-coated titanium electrode, belonging to the class of active anodes, showed a higher performance, achieving 78.8 ± 0.76 % contaminant degradation. Coupling iridium/ruthenium-coated titanium anode with a stainless-steel cathode improved the performance of the system, achieving even 96.2 ± 2.73 % of total nitrogen removal. The optimized cell configuration was used to treat livestock wastewater, resulting in the degradation of 67.0 ± 2.25 % of total nitrogen and 37.3 ± 0.68 % of total organic carbon when sodium chloride was added. At the end of the process, the ammonium content was completely removed, and only 17.7 ± 0.51 % of the initial nitrogen turned into nitrate. The results show that the proposed system is a promising approach to treating livestock wastewater by coupling high contaminant removal efficiencies with low operational costs. Anyway, further studies on process optimization with an emphasis on power requirements and electrode costs need to be carried out.

Interaction and band structure-determined inhibition of negative Cr (VI) and positive Fe (III) for antibiotic photodegradation by nitrogen-doped dissolved black carbon.

The influences of the positive Fe3+ and the negative Cr2O72- on the tetracycline (TC) photodegradation by N-doped dissolved black carbon (NDBC) have been investigated in this work. A series of samples (NDBC300, NDBC400 and NDBC500) have been extracted from the corresponding biochar. NDBC400 has the best photodegradation performance (79%) for TC under visible light irradiation. Adding Cr2O72- and Fe3+ can reduces TC photodegradation efficiency into 37% and 53%, respectively. This maybe from that Cr2O72- has stronger interaction with NDBC400 than Fe3+ since it can quench more fluorescence intensity of NDBC400 than Fe3+. Furthermore, Cr2O72- can reduce the steady-state concentration of 3NDBC400*, 1O2 and •OH, whereas Fe3+can just reduce the steady-state concentration of 3NDBC400* and increase the concentration of •OH. This may explain why Cr2O72- has stronger inhibit performance of TC photodegradation by NDBC400 than Fe3+. The band structures of NDBC400, NDBC400-Fe3+ and NDBC400-Cr2O72- are constructed. And the VB of NDBC400-Fe3+ has a stronger ability to produce •OH than NDBC400. In summary, coupling interaction and band structure characterization of NDBC400, NDBC400-Fe3+ and NDBC400-Cr2O72- can explain well why Cr2O72 has stronger inhibition effect than Fe3+ and Fe3+ can increase the concentration of •OH. This work provides a deep insight for the photochemical behavior of dissolved black carbon and the transformation behavior of the co-existed metal ions and antibiotics.

Impact of metal ions on PMS/Cl- disinfection efficacy: Enhancing or impeding microbial inactivation?

Peroxymonosulfate (PMS) is an eco-friendly disinfectant gaining attention. This study examined the influence of metal ions (Co(II), Cu(II), Fe(II)) on PMS disinfection with chloride ions (Cl-) against waterborne microorganisms, encompassing both bacteria and fungal spores. The findings elucidated that metal ions augment the inactivation of bacteria in the PMS/Cl- system while concurrently impeding the inactivation of fungal spores. Specifically, the PMS/Co(II)/Cl- process increased E. coli inactivation rates by 2.25 and 2.75 times compared to PMS/Co(II) and PMS/Cl-, respectively. Conversely, PMS/Me(II)/Cl- generally exhibited a diminished inactivation capacity against the three fungal spores compared to PMS/Cl-, albeit surpassing the efficacy of PMS/Me(II). For instance, the inactivation levels of A. niger by PMS/Cl-, PMS/Cu(II)/Cl-, and PMS/Cu(II) are 4.47-log, 1.92-log, and 0.11-log, respectively. Notably, fungal spores demonstrated a substantially higher resistance to disinfectants compared to bacteria. Differences in microbial susceptibility were linked to cell wall structure, composition, antioxidant defenses, and reactive species generation, such as hydroxyl radicals (•OH), sulfate radicals (SO4•-), and reactive chlorine species (RCS). This study demonstrated the novel and unique phenomenon of metal ions' dual role in modulating the PMS/Cl- disinfection process, which has not been reported before and has important implications for the field of water treatment.

Degradation of UV328 by ozone/peroxymonosulfate system: Performance and mechanisms.

2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentylphenol (UV328) is an emerging persistent organic pollutant ubiquitously found in environmental matrices. Though some advanced oxidation processes have been tested to degrade UV328 in waste streams, the degradation mechanisms are largely unknown. In this study, the degradation of UV328 by ozone (O3) and peroxymonosulfate (PMS) was systemically investigated. At neutral pH, 97.0% UV328 was removed in 5 min with 6.4 mg/min O3 and 2 mM PMS, and the degradation rate was positively correlated with the concentration of oxidants. Hydroxyl radical (•OH), sulfate radical (SO4•-) and singlet oxygen (1O2) participated in the degradation of UV328, in which 1O2 played a key role. Based on the identified transformation intermediates and density functional theory simulations, three degradation pathways of dehydrogenation, cycloaddition and hydroxylation were proposed. •OH and SO4•- radicals could attack UV328 through hydrogen atom abstraction channel. 1O2-mediated cycloaddition reaction is favorable, and •OH could react with UV328 via radical adduct formation pathway. Toxicity assessment indicated that O3/PMS treatment mitigated the ecological risks of UV328.

Oxygen and air cold plasma for the inactivation of Bacillus cereus in low-water activity soy powder.

Cold plasma (CP) technology is a promising alternative to thermal treatments for the microbial decontamination of foods with low-water activity. The aim of this work is study the application of low-pressure CP (0.35 mbar) for the inactivation of Bacillus cereus in a soybean powder matrix using O2 and synthetic air as ionizing gases. The parameters tested were an input power of 100, 200 and 300 W and an exposure time of 10 to 30 min. The excited reactive species formed were monitored by optical emission spectroscopy, and survival data were analyzed using the Weibull mathematical model. Treatments with both gases were effective in inactivating B. cereus. Air plasma resulted in a maximum 3.71-log reduction in bacterial counts at 300 W and 30 min, while O2 plasma showed the strongest inactivation ability, achieving levels higher than 5 log cycles at 300 W and > 25 min. This is likely due to the strong antimicrobial activity of oxygen-derived radicals together with carbon monoxide as an oxidation by-product. In addition, the Weibull distribution function accurately modeled the inactivation of B. cereus. Cold plasma technology is a promising approach for the decontamination of bacteria in low-water activity foods.

Effective peroxymonosulfate activation by lithium cobaltite recovered from spent lithium-ion batteries for enhanced carbamazepine degradation in a wide pH range.

Considering the high cost and complicated recycling process of spent lithium-ion batteries (SLIBs), transforming SLIBs into environment functional materials may be a wise approach. Herein, lithium cobaltite (LCO) cathode powders recovered from SLIBs were used to activate peroxymonosulfate (PMS) for removing carbamazepine (CBZ). The recovered LCO enables a 98.2% removal efficiency of CBZ (2.5 mg/L) within 10 min, which was effective at a broader pH range (pH = 5.0-11.0). The influence of key factors (initial pH, PMS, and catalyst dosage) and coexisting substances (SO42-, H2PO4-, NO3-, Cl-, HCO3-, and HA) on CBZ degradation were examined in detail. The primary radical species during the degradation of CBZ were proved to be 1O2, SO4-, and.OH that generated from PMS activation initiated by the valence change of Co in recovered LCO. The recovered LCO displayed excellent reusability with about 80.0% removal of CBZ after six cycles. Homogeneous activation of PMS mainly contributed to CBZ degradation in the first run, but the recovered LCO catalyst dominated the heterogeneous activation of PMS for the degradation of CBZ in the second to sixth run. Finally, the CBZ degradation pathways were presented based on the identified intermediates. This research has offered a new strategy of "treating wastes with wastes" to maximize the recycling of electronic wastes to remove emerging pollutants.

Nicotinamide riboside modulates the reactive species interactome, bioenergetic status and proteomic landscape in a brain-region-specific manner.

Nicotinamide riboside (NR), a precursor of nicotinamide adenine dinucleotide (NAD+), has robust cognitive benefits and alleviates neuroinflammation in Alzheimer's Disease (AD) mouse models without decreasing beta-amyloid plaque pathology. Such effects may be mediated by the reactive species interactome (RSI), at the metabolome level. In this study, we employed in vitro and in vivo models of oxidative stress, aging and AD to profile the effects of NR on neuronal survival, RSI, and the whole proteome characterization of cortex and hippocampus. RSI analysis yielded a complex modulation upon NR treatment. We constructed protein co-expression networks and correlated them to NR treatment and all measured reactive species. We observed brain-area specific effects of NR on co-expressed protein modules of oxidative phosphorylation, fatty acid oxidation, and neurotransmitter regulation pathways, which correlated with RSI components. The current study contributes to the understanding of modulation of the metabolome, specifically after NR treatment in AD and how it may play disease-modifying roles.

Efficient removal of moxifloxacin through PMS activation by CuFeS2/MXene.

Due to the frequent detection and potential toxicity of moxifloxacin (MOX), its removal technology had attracted attention in recent years. In this research, CuFeS2/MXene was prepared and used to activate peroxymonosulfate (PMS) to remove MOX. The degradation efficiencies, kinetics, influences, and reaction mechanism of MOX by CuFeS2/MXene/PMS were investigated. The synergistic effect of CuFeS2 and MXene significantly enhanced PMS activation, producing SO4•-, HO•, and 1O2 as the main active species. By adding 0.12 g/L CuFeS2/MXene and 0.12 mM PMS, MOX removal efficiency reached 99.1% within 40 min, with a rate constant of 0.1073 min-1. The composite ratios of CuFeS2/MXene impacted PMS activation more significantly than catalyst dosages and PMS concentrations. Acidic conditions were favorable for the degradation of MOX, while HCO3-, HPO42-, Mn2+, and HA had the inhibitory effects. Twelve major products were detected by HPLC-MS, and DFT was used to illustrate possible degradation pathways of MOX, including the removal of nitrogen-containing heterocycle and transformations of quinolone moieties. Toxicity analysis showed that the developmental toxicity, mutagenicity, and acute toxicity of degradation products tended to decrease. CuFeS2/MXene could exhibit excellent reusability, maintaining an average MOX degradation efficiency of 90.8% in the 7-cycle experiments.

Effects of chemically reactive species generated in plasma treatment on the physico-chemical properties and biological activities of polysaccharides: An overview.

Plasma technology as an advanced oxidation technology, has gained increasing interest to generate numerous chemically reactive species during the plasma discharge process. Such chemically reactive species can trigger a chain of chemical reactions leading to the degradation of macromolecules including polysaccharides. This review primarily summarizes the generation of various chemically reactive species during plasma treatment and their effects on the physico-chemical properties and biological activities of polysaccharides. During plasma treatment, the type of chemically reactive species that play a major role is related to equipment, working gases and types of polysaccharides. The primary chain structure of polysaccharides did not changed much during the plasma treatment, other physico-chemical properties might be changed, such as molecular weight, solubility, hydrophilicity, rheological properties, gel properties, crystallinity, elemental composition, glycosidic bonding, and surface morphology. Additionally, the biological activities of plasma-treated polysaccharides including antibacterial, antioxidant, immunological, antidiabetic activities, and seed germination promotion activities in agriculture could be improved. Therefore, plasma treatment has the potential application in preparing polysaccharides with enhanced biological activities.

Efficacy, kinetics, inactivation mechanism and application of cold plasma in inactivating Alicyclobacillus acidoterrestris spores.

As spores of Alicyclobacillus acidoterrestris can survive traditional pasteurization, this organism has been suggested as a target bacterium in the fruit juice industry. This study aimed to investigate the inactivation effect of cold plasma on A. acidoterrestris spores and the mechanism behind the inactivation. The inactivation effect was detected by the plate count method and described by kinetic models. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), the detection of dipicolinic acid (DPA) release and heat resistance detection, the detection and scavenging experiment of reactive species, and cryo-scanning electron microscopy were used to explore the mechanism of cold plasma inactivation of A. acidoterrestris. The results showed that cold plasma can effectively inactivate A. acidoterrestris spores in saline with a 3.0 ± 0.3 and 4.4 ± 0.8 log reduction in CFU/mL, for 9 and 18 min, respectively. The higher the voltage and the longer the treatment time, the stronger the overall inactivation effect. However, a lower gas flow rate may increase the probability of spore contact with reactive species, resulting in better inactivation results. The biphasic model fits the survival curves better than the Weibull model. SEM and TEM revealed that cold plasma treatment can cause varying degrees of damage to the morphology and structure of A. acidoterrestris spores, with at least 50 % sustaining severe morphological and structural damage. The DPA release and heat resistance detection showed that A. acidoterrestris spores did not germinate but died directly during the cold plasma treatment. 1O2 plays the most important role in the inactivation, while O3, H2O2 and NO3- may also be responsible for inactivation. Cold plasma treatment for 1 min reduced A. acidoterrestris spores in apple juice by 0.4 ± 0.0 log, comparable to a 12-min heat treatment at 95 °C. However, as the treatment time increased, the survival curve exhibited a significant tailing phenomenon, which was most likely caused by the various compounds in apple juice that can react with reactive species and exert a physical shielding effect on spores. Higher input power and higher gas flow rate resulted in more complete inactivation of A. acidoterrestris spores in apple juice. What's more, the high inactivation efficiency in saline indicates the cold plasma device provides a promising alternative for controlling A. acidoterrestris spores during apple washing. Overall, our study provides adequate data support and a theoretical basis for using cold plasma to inactivate A. acidoterrestris spores in the food industry.

Roles of soil minerals in the degradation of chlorpyrifos and its intermediate by microwave activated peroxymonosulfate.

Soil mineral is one of the important factors that affecting oxidant decomposition and pollutants degradation in soil remediation. In this study, the effects of iron minerals, manganese minerals and clay minerals on the degradation of chlorpyrifos (CPF) and its intermediate product 3,5,6-trichloro-2-pyridinol (TCP) by microwave (MW) activated peroxymonosulfate (PMS) were investigated. As a result, the addition of minerals had slight inhibitory effect on the degradation efficiency of CPF by MW/PMS, but the degradation efficiency of TCP was improved by the addition of some specific minerals, including ferrihydrite, birnessite, and random symbiotic mineral of pyrolusite and ramsdellite (Pyr-Ram). The stronger MW absorption ability of minerals is beneficial for PMS decomposition, but the MW absorption ability of minerals cannot be fully utilized because of the weaker MW radiation intensity under constant temperature conditions. Through electron spin resonance test, quenching experiment and electrochemical experiment, electron transfer, SO4- and OH, SO4- dominated TCP degradation by MW/PMS with the addition of birnessite, Pyr-Ram and ferrihydrite, respectively. Besides, the adsorption effect of ferrihydrite also enhanced the removal of TCP. The redox of Mn (III)/Mn (IV) or Fe (II)/Fe (III) in manganese/iron minerals participated in the generation of reactive species. In addition, the addition of minerals not only increased the variety of alkyl hydroxylation products of CPF, causing different degradation pathways from CPF to TCP, but also further degraded TCP to dechlorination or hydroxylation products. This study demonstrated the synergistic effect of minerals and MW for PMS activation, provided new insights for the effects of soil properties on soil remediation by MW activated PMS technology.

Plasma-generated RONS in liquid transferred into cryo-microneedles patch for skin treatment of melanoma.

Malignant melanoma is the most lethal form of skin cancer. As a promising anti-cancer agent, plasma-activated water (PAW) rich in reactive oxygen and nitrogen species (RONS) has shown significant potential for melanoma treatment. However, rapid decay of RONS and inefficient delivery of PAW in conventional injection methods limit its practical applications. To address this issue, here we report a new approach for the production of plasma-activated cryo-microneedles (PA-CMNs) patches using custom-designed plasma devices and processes. Our innovation is to incorporate PAW into the PA-CMNs that are fabricated using a fast cryogenic micro-molding method. It is demonstrated that PA-CMNs can be easily inserted into skin to release RONS and slow the decay of RONS thereby prolonging their bioactivity and effectiveness. The new insights into the effective melanoma treatment suggest that the rich mixture of RONS within PA-CMNs prepared by custom-developed hybrid plasma-assisted configuration induces both ferroptosis and apoptosis to selectively kill tumor cells. A significant inhibition of subcutaneous A375 melanoma growth was observed in PA-CMNs-treated tumor-bearing nude mice without any signs of systemic toxicity. The new approach based on PA-CMNs may potentially open new avenues for a broader range of disease treatments.

Free radicals and oxidative stress: Mechanisms and therapeutic targets: Review article.

BACKGROUND: Free radicals are small extremely reactive species that have unpaired electrons. Free radicals include subgroups of reactive species, which are all a product of regular cellular metabolism. Oxidative stress happens when the free radicals production exceeds the capacity of the antioxidant system in the body's cells. OBJECTIVE: The current review clarifies the prospective role of antioxidants in the inhibition and healing of diseases. METHODS: Information on oxidative stress, free radicals, reactive oxidant species, and natural and synthetic antioxidants was obtained by searching electronic databases like PubMed, Web of Science, and Science Direct, with articles published between 1987 and 2023 being included in this review. RESULTS: Free radicals exhibit a dual role in living systems. They are toxic byproducts of aerobic metabolism that lead to oxidative injury and tissue disorders and act as signals to activate appropriate stress responses. Endogenous and exogenous sources of reactive oxygen species are discussed in this review. Oxidative stress is a component of numerous diseases, including diabetes mellitus, atherosclerosis, cardiovascular disease, Alzheimer's disease, Parkinson's disease, and cancer. Although various small molecules assessed as antioxidants have shown therapeutic prospects in preclinical studies, clinical trial outcomes have been inadequate. Understanding the mechanisms through which antioxidants act, where, and when they are active may reveal a rational approach that leads to more tremendous pharmacological success. This review studies the associations between oxidative stress, redox signaling, and disease, the mechanisms through which oxidative stress can donate to pathology, the antioxidant defenses, the limits of their effectiveness, and antioxidant defenses that can be increased through physiological signaling, dietary constituents, and probable pharmaceutical interference. Prospective clinical applications of enzyme mimics and current progress in metal- and non-metal-based materials with enzyme-like activities and protection against chronic diseases have been discussed. CONCLUSION: This review discussed oxidative stress as one of the main causes of illnesses, as well as antioxidant systems and their defense mechanisms that can be useful in inhibiting these diseases. Thus, the positive and deleterious effects of antioxidant molecules used to lessen oxidative stress in numerous human diseases are discussed. The optimal level of vitamins and minerals is the amount that achieves the best feed benefit, best growth rate, and health, including immune efficiency, and provides sufficient amounts to the body.

Morinda citrifolia Essential Oil: A Plant Resistance Biostimulant and a Sustainable Alternative for Controlling Phytopathogens and Insect Pests.

With the growing demand for sustainable and safe agricultural practices, plant compounds emerge as a solution for biological activities. Here, we evaluated the potential of using Morinda citrifolia essential oil to induce plant resistance and to control phytopathogens (Curvularia lunata) and insect pests (Daubulus maidis). We conducted a chromatographic analysis to unveil the essential oil components. We also quantified the activity levels of antioxidant enzymes and chitinase for resistance induction. The antifungal action was evaluated through disease progression and the inhibition of mycelial growth in addition to in silico studies that made it possible to predict the interaction site between the fungal protein and the compounds. We assessed the toxicity and repellent actions towards the D. maidis. Octanoic acid (58.43%) was identified as the essential oil major compound. Preventive treatment with essential oil and octanoic acid (25.0 µL mL-1) increased not only the plant defense activities (i.e., the activity of the enzymes superoxide dismutase, catalase, phenol peroxidase, ascorbate peroxidase, and chitinase) but also controlled Curvularia leaf spot. The stable interactions between octanoic acid and tyrosine-tRNA ligase from C. lunata suggested protein synthesis inactivation. The essential oil inhibited 51.6% of mycelial growth, and this effect was increased to 75.9% with the addition of adjuvants (i.e., angico gum). The essential oil reduced 76% of the population of D. maidis adults and repelled 50% of the number of D. maidis after 48 h under field conditions. The repellency effect in the field reduced the population of D. maidis adults, transmitters of the stunting complex, by 50%. The results highlight the potential of M. citrifolia as a resistance activator, fungicide, insecticide, and an effective biorational alternative.

Plasma-Activated Tap Water with Oxidative Potential Has an Inactivating Effect on Microbiological Contaminants in Aqueous Suspensions.

Plasma-activated water (PAW) generated from tap water has gained attention as a disinfectant when used directly in its pure form. Little is known about the application of PAW for bacterial inactivation in aqueous environments because its use in fluids results in dilutions. We investigated the effect of PAW in aqueous suspensions simulating such dilutions, and we focused on the minimal addition of PAW volumes to bacterial aqueous suspensions still resulting in high inactivation rates. The antimicrobial effect was highly dependent on the activation of PAW. An increase in activation power from 90 to 100 W resulted in a greater microbial reduction with an identical 10 min activation time. The susceptibility to PAW dilutions was analyzed in detail regarding nine Gram-negative species out of Enterobacterales and other waterborne microorganisms as well as four Gram-positive species present in two different matrices, in saline and in tap water, at high concentrations simulating massive contamination situations. For this purpose, the PAW activation setting of 90 W and 30 min was defined in order to be able to differentiate the limitations of inactivation in individual bacterial species. The Gram-negatives in saline demonstrated susceptibility when one volume unit of PAW was added. However, twice the PAW volume was necessary for inactivation when bacteria were present in tap water. Gram-positive microorganisms were more robust, indicated by prolonged contact times before inactivation. Our results indicate that PAW can be used for bacterial decontamination processes in aqueous environments when added in surplus. Optimized activation settings such as electric power to generate PAW and the contact times to the samples increase the effect of the inactivation a wide range of bacteria, regardless of their resistance profiles.