Roles of oxides of nitrogen on quality enhancement of soybean sprout during hydroponic production using plasma discharged water recycling technology

The pH acidity and nitrate accumulation by plasma discharge enhanced the growth and phytochemicals of soybean sprouts grown in reused water

This study investigated the effect of plasma treatment on reused water and evaluated the interactions of the plasma-treated water (PTW) with plants or microbes to determine the optimal PTW for reuse. The repeated treatment gradually accumulated nitrate (NO3-) in the PTW and lowered its pH; afterward, it led to the sprouted soybeans accumulating other inorganic ions in the PTW. The biomass of soybean sprouts was enhanced by the accumulated NO3- but decreased due to the pH effect. Meanwhile, the acidic pH reduced the microbial counts, but they increased after sprinkling the PTW over the sprouts. The optimal PTW in our study, which had a gradual increase of NO3- (≤321.8 mg·L-1) with an acceptable pH (≥pH 3), significantly enhanced the biomass by 4.2% compared to the untreated control. Additionally, it increased the total content of amino acids and isoflavones by 9% and 18% in the growing part, respectively.

Investigating the effectiveness of LED lighting in the production of rich sprouts for food purposes

In recent times, there has been a surge in interest in the impact of diet and physical activity on human health, with the goal of expanding lifespan and enhancing the quality of life. This has Light-emitting diode (LED) to interventions centered on incorporating healthy foods, including fresh sprouts, which are rich in antioxidant compounds and beneficial phytonutrients for human consumption. Various factors, such as temperature, nutritional solution, and types of light quality and intensity, can influence the nutritional value of sprouts. This study evaluates the impact of LED light with red-blue-ultraviolet (6:3:1; R:B:UV) and three levels of intensity (control, 120, and 150 μmol/m²s^-1) on five different sprout species, namely wheat, barley, mung bean, alfalfa, and soybean, after seven days of germination. The research investigates the effects on various parameters, including photosynthetic pigments (chlorophylls a, b, total), carotenoid, activities of antioxidant enzymes such as catalase, superoxide dismutase, and soluble proteins, soluble sugars, starch, vitamin C, and element content such as potassium, iron, and phosphorus. The results indicate that the LED treatments and increasing light intensity significantly improve the physiological and antioxidant properties of edible sprouts, with the 150 μmol/m²s^-1 treatment producing the most beneficial outcomes. Additionally, increasing light intensity reduces starch content while enhancing the content of photosynthetic pigments, soluble carbohydrates, vitamin C, element concentration, antioxidant enzymes, and soluble proteins. Among the five species of edible sprouts, barley had the highest content of photosynthetic pigments, while soybean and mung beans had the lowest content. Mung beans and alfalfa had the highest and lowest concentrations of potassium and iron, respectively. In terms of phosphorus concentration, soybean and barley sprouts showed the highest and lowest concentrations, respectively.

Scanning electron microscopy, biochemical and enzymatic studies to evaluate hydro-priming and cold plasma treatment effects on the germination of Salvia leriifolia Benth. seeds

Finding a suitable method to increase seed germination rates of medicinal plants is critical to saving them from extinction. The effects of cold plasma (CP) treatments (using surface power densities of 80 and 100 W, with exposure times of 0, 120, 180, and 240 s) and incorporating hydropriming (carried out for 24 and 2 h on normal and uncovered seeds, respectively) to enhance the seed germination of Salvia leriifolia Benth a native endangered Iranian medicinal plant, were evaluated in this study. Scanning electron microscopy (SEM) images identified more destroyed mesh-like structures in hydro-primed and uncovered seeds than in normal and dry seeds. In comparison to the control, and other treatments, employing 100 W of CP for 240 s produced the maximum germination percentage and rate, as well as a seedling vigor of I and II in hydro-primed and uncovered seeds. The levels of α-amylase activity increased when the power and exposure times of CP were increased. The uncovering and hydropriming of S. leriifolia seeds resulted in increased enzyme activity. Malondialdehyde (MDA) and hydrogen peroxide (H2O2) contents were enhanced by increasing the power and exposure time of CP, especially in uncovered and hydro-primed seeds. The activity of antioxidant enzymes, including catalase (CAT) and superoxide dismutase (SOD), was correlated to changes in MDA and H2O2 levels. Finally, direct contact of CP with uncovered seeds in a short exposure time can improve the germination of S. leriifolia seeds via microscopic etching and activation of enzymes.

The Modulatory Effects of Non-Thermal Plasma on Seed’s Morphology, Germination and Genetics—A Review

Non-thermal plasma (NTP) is a novel and promising technique in the agricultural field that has the potential to improve vegetal material by modulating the expression of various genes involved in seed germination, plant immune response to abiotic stress, resistance to pathogens, and growth. Seeds are most frequently treated, in order to improve their ability to growth and evolve, but the whole plant can also be treated for a fast adaptive response to stress factors (heat, cold, pathogens). This review focuses mainly on the application of NTP on seeds. Non-thermal plasma treated seeds present both external and internal changes. The external ones include the alterations of seed coat to improve hydrophilicity and the internal ones refer to interfere with cellular processes that are later visible in metabolic and plant biology modifications. The usage of plasma aims to decrease the usage of fertilizers and pesticides in order to reduce the negative impact on natural ecosystem and to reduce the costs of production.

Effects of Non-Thermal Plasma Treatment on Seed Germination and Early Growth of Leguminous Plants-A Review

The legumes (Fabaceae family) are the second most important agricultural crop, both in terms of harvested area and total production. They are an important source of vegetable proteins and oils for human consumption. Non-thermal plasma (NTP) treatment is a new and effective method in surface microbial inactivation and seed stimulation useable in the agricultural and food industries. This review summarizes current information about characteristics of legume seeds and adult plants after NTP treatment in relation to the seed germination and seedling initial growth, surface microbial decontamination, seed wettability and metabolic activity in different plant growth stages. The information about 19 plant species in relation to the NTP treatment is summarized. Some important plant species as soybean (Glycine max), bean (Phaseolus vulgaris), mung bean (Vigna radiata), black gram (V. mungo), pea (Pisum sativum), lentil (Lens culinaris), peanut (Arachis hypogaea), alfalfa (Medicago sativa), and chickpea (Cicer aruetinum) are discussed. Likevise, some less common plant species i.g. blue lupine (Lupinus angustifolius), Egyptian clover (Trifolium alexandrinum), fenugreek (Trigonella foenum-graecum), and mimosa (Mimosa pudica, M. caesalpiniafolia) are mentioned too. Possible promising trends in the use of plasma as a seed pre-packaging technique, a reduction in phytotoxic diseases transmitted by seeds and the effect on reducing dormancy of hard seeds are also pointed out.

Degradation of different pesticides in water by microplasma: the roles of individual radicals and degradation pathways

Pesticides are emergent toxins often identified in aquatic environments. In the present study, microplasma was employed to reduce the pesticide content in water. The degradation efficacy, rate, and pathways of standard organophosphorus pesticides (namely, chlorpyrifos, chlorpyrifos oxone, and diazinone) and an organochlorine pesticide (namely, DDT solution) were evaluated using microplasma. High-performance liquid chromatography (HPLC) analysis was performed to elucidate the degradation efficiency of pesticides as a function of plasma-produced substances that originally contributed to the main reduction procedure. Microplasma produces several types of radicals or reactive substances, for instance dissolved ozone (O₃), nitrogen oxides, hydroxyl radicals (OH radicals), and hydrogen peroxide (H₂O₂). The removal potential differs due to the existence or absence of varieties of plasma-produced substances. The functions of major plasma-produced species on pesticide removal were determined by a passive technique. Nitrogen oxides showed a key role in organophosphorus pesticide removal, whereas dissolved ozone and OH radicals played major roles in DDT degradation. HPLC data showed that plasma-induced pesticide removal showed first-order reaction kinetics. The pesticide removal pathways through microplasma were validated by investigating the achieved data from LC-MS and GC-MS.

A review on recent advances in plasma-activated water for food safety: current applications and future trends

Plasma-activated water (PAW), the water or solutions treated with atmospheric cold plasma, is an eco-friendly technique with minimal changes in food products, making it a befitting alternative to traditional disinfection methods. Due to its potential microbicidal properties, PAW has been receiving increasing attention for applications in the food, agricultural, and biomedical fields. In this article, we aimed at presenting an overview of recent studies on the generation methods, physicochemical properties, and antimicrobial activity of PAW, as well as its application in the food industry. Specific areas were well discussed including microbial decontamination of food products, reduction of pesticide residues, meat curing, sprouts production, and disinfection of food contact materials. In addition, the factors influencing PAW efficiency were also well illustrated in detail, such as discharge parameters, types and amounts of microorganisms, characteristics of the liquid solution and food products, and treatment time. Moreover, the strategies to improve the efficacy of PAW were also presented in combination with other technologies. Furthermore, the salient drawbacks of this technology were discussed and the important areas for future research were also highlighted. Overall, the present review provides important insights for the application of PAW in the food industry.

The Effects of Plasma on Plant Growth, Development, and Sustainability

Cold atmospheric or low pressure plasma has activation effects on seed germination, plant growth and development, and plant sustainability, and prior experimental studies showing these effects are summarized in this review. The accumulated data indicate that the reactive species generated by cold plasma at atmospheric or low pressure may be involved in changing and activating the physical and chemical properties, physiology, and biochemical and molecular processes in plants, which enhances germination, growth, and sustainability. Although laboratory and field experiments are still required, plasma may represent a tool for efficient adaptation to changes in the climate and agricultural environments.

Emerging Plasma Technology That Alleviates Crop Stress During the Early Growth Stages of Plants: A Review

Crops during their early growth stages are vulnerable to a wide range of environmental stressors; thus, earlier seed invigoration and seedling establishment are essential in crop production. As an alternative to synthetic chemical treatments, plasma technology could be one of the emerging technologies to enhance seed germination and seedling vigor by managing environmental stressors. Recent studies have shown its beneficial effects in various stress conditions, suggesting that plasma treatment can be used for early crop stress management. This paper reviewed the effects of different types of plasma treatments on plant responses in terms of the seed surface environment (seed scarification and pathogen inactivation) and physiological processes (an enhanced antioxidant system and activated defense response) during the early growth stages of plants. As a result, plasma treatment can enhance seed invigoration and seedling establishment by alleviating the adverse effects of environmental stressors such as drought, salinity, and pathogen infection. More information on plasma applications and their mechanisms against a broad range of stressors is required to establish a better plasma technology for early crop stress management.