Cold Treatment Research Articles

Exploring the impact of cold plasma treatment on the antioxidant capacity, ascorbic acid, phenolic profile, and bioaccessibility of fruits and fruit juices

AbstractIn recent years, cold plasma (CP) has emerged as a promising preservation technology for fruit products. Several CP sources include dielectric barrier discharge, plasma jets, corona discharges, micro‐discharges, glow discharges, and gliding arc discharges. However, the effects of these different types of CP on the chemical compounds of fruits and juices are not fully understood. In this review, we summarize (I) the current knowledge on the use of CP for the preservation and processing of fruits and juices; (II) the diverse types of CP sources and explore their applications within a scientific context; (III) the physicochemical transformations that take place in fruits and juices following CP treatment; and (IV) the changes observed in antioxidant activity, vitamin C content, phenolic compounds, and their bioaccessibility. Numerous studies have explored CP's influence on microbial contamination, shelf life, enzymes, and various physicochemical changes. This review uniquely centers its attention on the impact of CP on bioactive phenolic compounds, their bioaccessibility, vitamin C content, and antioxidant activity in different types of fruits and fruit juices. Additionally, this review delves into the assessment of selected sensory properties, notably color, which is an important parameter for consumer acceptance. By focusing on these particular aspects, we aim to provide a targeted and comprehensive analysis of CP's effects on essential nutritional and quality attributes of fruits and fruit juices, distinct from the broader spectrum covered in the existing literature.

Doubled Haploid Lines Derived from a European Maize Flint Landrace Contrast in Recovery from Cold Stress

Suboptimal temperatures at sowing and emergence affect the early development of maize, with potentially irreversible effects later in the growing season. We studied recovery from cold stress of an inbred line (B73) and 13 Doubled Haploid lines derived from a European flint maize landrace. After a cold treatment (20–12 °C, day–night) from sowing to seedling establishment, seedlings were transplanted and grown in the greenhouse until the V8 stage (eight leaves fully developed), when we measured agronomically relevant plant traits and spectral indices of mature leaves. Survival rates of transplanted seedlings after cold treatment ranged from 10% to 100%. After a strong delay in early development due to cold, the surviving plants were able to compensate for this delay at later stages of recovery. They reached the V8 stage after only five more growing degree days than plants grown under the control treatment (25–18 °C, day–night). Plants from the most cold-tolerant genotypes (PE0401 and PE0100) accumulated more root and shoot biomass at the end of the recovery phase compared with the same genotypes exposed to the control treatment. The genotypes with the most plastic leaf morphological traits (PE0161 and PE0072) had little reduction in leaf biomass at the end of the recovery phase in comparison with less responsive genotypes such as PE0171. We conclude that genotypes that survived cold treatment with minimal cold damage of seedling leaves can be candidates for further cold recovery studies and breeding. Nevertheless, such studies must take trait acclimation for other suboptimal conditions into consideration.

Polyamines-Mediated amelioration of cold treatment in wheat: Insights from morpho-physiological and biochemical features and PAO genes expression analyses

Polyamines (PAs) are small molecules that exist in all living organisms. They play a crucial role in various physiological processes in plants, including growth, development and responses to stress. Cold stress is one of the major abiotic stresses that has a negative effect on the growth, development and productivity of plants. In the present study, exogenous PAs (Spd, Put and distilled water as control) were efficiently used in mitigating of stress effects in two contrasting wheats cultivars (‘Mihan’ and ‘Rakhshan’) grown under cold conditions. Shoot and root dry weight, chlorophyll, carotenoid, proline contents, catalase and ascorbate peroxidase activities were improved by PA application (10 mg L−1 foliar spray) in the cold-stressed plants. The gene expression analysis with RT-qPCR showed transcriptional variation of selected genes in response to cold condition and PAs. Under cold condition the expression levels of genes responsible for the synthesis (TaADC, TaSAMDC, TaSPDS) and catabolism (TaPAO11–7B TaPAO11–7D) increased in both cultivars, but at higher level in the tolerant one. These results reveal a significant role of PAs under cold acclimation in wheat leaves.

In Silico Identification and Characterization of Rare Cold Inducible 2 (RCI2) Gene Family in Cotton.

RCI2/PMP3s are involved in biotic and abiotic stresses and have an influence on the regulation of many genes. RCI2/PMP3 genes, which particularly encode small membrane proteins of the PMP3 family, are involved in abiotic stress responses in plants. In this work, in silico studies were used to investigate RCI2's potential function in stress tolerance and organogenesis. We conducted an extensive study of the RCI2 gene family and revealed 36 RCI2 genes from cotton species that were distributed over 36 chromosomes of the cotton genome. Functional and phylogenetic examination of the RCI2/PMP3 gene family has been studied in Arabidopsis, but in cotton, the RCI2/PMP3 genes have not yet been studied. Phylogenetic and sequencing studies revealed that cotton RCI2s are conserved, with most of them categorized into six distinct clades. A chromosome distribution and localization study indicated that cotton RCI2 genes were distributed unevenly on 36 chromosomes with segmental duplications, suggesting that the cotton RCI2 family is evolutionarily conserved. Many cis-elements related to stress responsiveness, development, and hormone responsiveness were detected in the promoter regions of the cotton RCI2. Moreover, the 36 cotton RCI2s revealed tissue-specific expression patterns in the development of cotton performed by transcriptome analysis. Gene structure analysis indicated that nearly all RCI2 genes have two exons and one intron. All of the cotton RCI2 genes were highly sensitive to drought, abscisic acid, salt, and cold treatments, demonstrating that they may be employed as genetic objects to produce stress-resistant plants.

Pan-transcriptomic analysis reveals alternative splicing control of cold tolerance in rice.

Plants have evolved complex mechanisms to adapt to harsh environmental conditions. Rice (Oryza sativa) is a staple food crop that is sensitive to low temperatures. However, its cold stress responses remain poorly understood, thus limiting possibilities for crop engineering to achieve greater cold tolerance. In this study, we constructed a rice pan-transcriptome and characterized its transcriptional regulatory landscape in response to cold stress. We performed Iso-Seq and RNA-Seq of 11 rice cultivars subjected to a time-course cold treatment. Our analyses revealed that alternative splicing-regulated gene expression plays a significant role in the cold stress response. Moreover, we identified CATALASE C (OsCATC) and Os03g0701200 as candidate genes for engineering enhanced cold tolerance. Importantly, we uncovered central roles for the 2 serine-arginine-rich proteins OsRS33 and OsRS2Z38 in cold tolerance. Our analysis of cold tolerance and resequencing data from a diverse collection of 165 rice cultivars suggested that OsRS2Z38 may be a key selection gene in japonica domestication for cold adaptation, associated with the adaptive evolution of rice. This study systematically investigated the distribution, dynamic changes, and regulatory mechanisms of alternative splicing in rice under cold stress. Overall, our work generates a rich resource with broad implications for understanding the genetic basis of cold response mechanisms in plants.

Transcription factor DcbZIPs regulate secondary metabolism in Dendrobium catenatum during cold stress.

Cold stress seriously affects plant development and secondary metabolism. The basic region/leucine zipper (bZIP) is one of the largest transcription factor (TFs) family and widely involved in plant cold stress response. However, the function of bZIP in Dendrobium catenatum has not been well-documented. Cold inhibited the growth of D. catenatum and increased total polysaccharide and alkaloid contents in stems. Here, 62 DcbZIP genes were identified in D. catenatum, which were divided into 13 subfamilies. Among them, 58 DcbZIPs responded to cold stress, which were selected based on the transcriptome database produced from cold-treated D. catenatum seedlings. Specifically, the expression of DcbZIP3/6/28 was highly induced by cold treatment in leaves or stems. Gene sequence analysis indicated that DcbZIP3/6/28 contains the bZIP conserved domain and is localized to the cell nucleus. Co-expression networks showed that DcbZIP6 was significantly negatively correlated with PAL2 (palmitoyl-CoA), which is involved in flavonoid metabolism. Moreover, DcbZIP28 has significant negative correlations with various metabolism-related genes in the polysaccharide metabolic pathway, including PFKA1 (6-phosphofructokinase), ALDO2 (aldose-6-phosphate reductase) and SCRK5 (fructokinase). These results implied that DcbZIP6 or DcbZIP28 are mainly involved in flavonoid or polysaccharide metabolism. Overall, these findings provide new insights into the roles of the DcbZIP gene family in secondary metabolism in D. catenatum under cold stress.

A UPLC-MS/MS method for quantification of β-N-methylamino-L-alanine (BMAA) in Cycas sphaerica roxb. And validating efficacy of a traditional BMAA removal method

The presence of neurotoxin β-N-Methylamino-L-alanine (BMAA) in the seeds of Cycas sphaerica is reported for first time. We developed a UPLC-MS/MS method for BMAA quantification by derivatizing with dansyl chloride. The method successfully differentiated L-BMAA from its structural isomer2,4-diaminobutyric acid (DAB).The extracting mixture 0.1M TCA: ACN 4:1 v/v had a recovery level of >95%. The method is a high throughput sensitive chromatographic technique with 16.42 ng g−1 Limit of Quantification. BMAA was present in the endosperm of C. sphaerica, and was not detected in the leaves and pith. Washing of seeds in running cold water for 48 h reduced BMAA content by 86%. The local communities also treat the seeds under running cold water, but only for 24 h. The results of the study thus validated the traditional BMAA removal process through cold water treatment, but recommend for increase in the treatment period to 48 h or more.

Modeling the inactivation kinetics of polyphenol oxidase and peroxidase during the cold plasma treatment of kiwifruit juice

AbstractCold Plasma (CP) is an emerging non‐thermal technology that preserves and decontaminates food. Kiwifruit juice spoilage enzymes polyphenol oxidase (PPO) and peroxidase (POD) were studied at 24‐36 kV, 2‐10 mm juice depth, and 2‐10 min treatment time using log‐linear, Weibull distribution, and logistic models. The Weibull and logistic model explained enzyme inactivation kinetics well based on goodness of fit (Coefficient of determination: 0.97‐0.99 & root mean square error: 0.11‐2.15) and validation indices (accuracy factor: 1‐1.06 and bias factor: 0.96‐1.04). The logistic model suited PPO and POD inactivation curves well, with the least Akaike weight in 71.29% and 61.45%, respectively. POD had a half‐maximal activity of 11.37, 5.22, and 3.60 min at 24 kV, 30 kV, and 36 kV at 6 mm juice depth, compared to 8.71, 4.41, and 2.51 min for PPO. This shows that POD is more CP‐resistant than PPO, making its inactivation in kiwifruit juice crucial.Practical ApplicationKinetic modeling helps to comprehend the fundamental process and is suitable for improving the inactivation process and enhancing its efficacy. As a relatively primary method, mathematical models facilitate a greater comprehension of the mechanism and factors influencing the inactivation processes. This study involves the inactivation of PPO and POD to produce a stable kiwifruit juice. The inactivation of PPO and POD enzymes will prevent the undesirable enzymatic browning of juice. The kinetic data related to enzyme inactivation will help in deciding the process parameters like plasma voltage, juice depth, and treatment time for producing enzymatically stable kiwifruit juice.

Full-length transcriptome reveals the pivotal role of ABA and ethylene in the cold stress response of Tetrastigma hemsleyanum.

Tetrastigma hemsleyanum is a valuable herb widely used in Chinese traditional and modern medicine. Winter cold severely limits the artificial cultivation of this plant, but the physiological and molecular mechanisms upon exposure to cold stress in T. hemsleyanum are unclear. T. hemsleyanum plants with different geographical origins exhibit large differences in response to cold stress. In this research study, using T. hemsleyanum ecotypes that exhibit frost tolerance (FR) and frost sensitivity (FS), we analyzed the response of cottage seedlings to a simulated frost treatment; plant hormones were induced with both short (2 h) and long (9 h) frost treatments, which were used to construct the full-length transcriptome and obtained 76,750 transcripts with all transcripts mapped to 28,805 genes, and 27,215 genes, respectively, annotated to databases. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed enrichment in plant hormone signaling pathways. Further analysis shows that differently expressed genes (DEGs) concentrated on calcium signaling, ABA biosynthesis and signal transduction, and ethylene in response to cold stress. We also found that endogenous ABA and ethylene content were increased after cold treatment, and exogenous ABA and ethylene significantly improved cold tolerance in both ecotypes. Our results elucidated the pivotal role of ABA and ethylene in response to cold stress in T. hemsleyanum and identified key genes.

Combined of plasma-activated water and dielectric barrier discharge atmospheric cold plasma treatment improves the characteristic flavor of Asian sea bass (Lates calcarifer) through facilitating lipid oxidation

To explore the combination effects of plasma-activated water and dielectric barrier discharge (PAW-DBD) cold plasma treatment on the formation of volatile flavor and lipid oxidation in Asian sea bass (ASB), the volatile flavor compounds and lipid profiles were characterized by gas chromatography-ion mobility spectrometry and LC-MS-based lipidomics analyses. In total, 38 volatile flavor compound types were identified, and the PAW-DBD group showed the most kinds of volatile components with a significant (p < 0.05) higher content in aldehydes, ketones, and alcohols. A total of 1500 lipids was detected in lipidomics analysis, phosphatidylcholine was the most followed by triglyceride. The total saturated fatty acids content in PAW-DBD group increased by 105.02 μg/g, while the total content of unsaturated fatty acids decreased by 275.36 μg/g. It can be concluded that the PAW-DBD processing increased both the types and amounts of the volatile flavor in ASB and promoted lipid oxidation by altering lipid profiles.

СОВРЕМЕННЫЕ ЗАДАЧИ НАУЧНЫХ ИССЛЕДОВАНИЙ В ОБЛАСТИ ВИНОДЕЛИЯ

The article presents the results of research activities for 2023 of the Federal State Budget Scientific Institution All-Russian National Research Institute of Viticulture and Winemaking Magarach of the RAS in the field of winemaking, carried out in accordance with the Program of Fundamental Scientific Research in the Russian Federation for the long term (2021-2030). The methodology of wine quality management with ecostatus has been created, aimed at revealing the individual characteristics of wines caused by natural factors and reducing the risks of negative effects on humans. Promising yeast strains have been identified: Steinberg, Champanskaya G-14, ShM-30, Novocimlyanskaya 3 with a description of their taxonomic affiliation, morphological and physiological-biochemical properties. Two strains of O. oeni active acid-reducing agents are recommended for practical use. The application of technology for the production of young sparkling wines of Crimean autochthonous grape The article presents the results of research activities for 2023 of the Federal State Budget Scientific Institution All-Russian National Research Institute of Viticulture and Winemaking Magarach of the RAS in the field of winemaking, carried out in accordance with the Program of Fundamental Scientific Research in the Russian Federation for the long term (2021-2030). The methodology of wine quality management with ecostatus has been created, aimed at revealing the individual characteristics of wines caused by natural factors and reducing the risks of negative effects on humans. Promising yeast strains have been identified: Steinberg, Champanskaya G-14, ShM-30, Novocimlyanskaya 3 with a description of their taxonomic affiliation, morphological and physiological-biochemical properties. Two strains of O. oeni active acid-reducing agents are recommended for practical use. The application of technology for the production of young sparkling wines of Crimean autochthonous grape varieties: Kokur belyi, Sary Pandas, Soldaiya and Kefesiya is justified. The system of criteria indicators for assessing the quality of grapes for the production of high-quality cognac distillates and cognacs is substantiated. A working collection of 63 natural strains of lactic acid bacteria has been formed. The optimal technological factors of the process of single-stage extraction by infusing with a food water-alcohol solution of green grape shoots of the Vitis vinifera, Vitis abrusca species have been established, allowing to increase the yield of total polyphenols by at least 2.6 times for the production of functional products. The most optimal technological modes of cold treatment of dry and fortified wine materials have been established to substantiate the constructive solution of an energy-saving installation for the purpose of cold treatment of wine materials based on the study of the main factors affecting the mass transfer process of potassium bitartrate crystallization. The obtained results of research work contribute to improving the quality of domestic wine products and expanding its production, including winemaking with ecological and geographical statuses, the production of domestic cognac and grape processing products of a functional orientation. The introduction of scientific developments into production will increase the competitiveness of domestic wine products, accelerate import substitution and ensure the country's food independence.

An 18-day, 3 °C cold treatment effectively kills Ceratitis capitata (Diptera: Tephritidae) in kiwifruit (Actinidia spp.).

A series of experiments were carried out to develop a phytosanitary disinfestation protocol to kill Ceratitis capitata (Weidemann) (Mediterranean fruit fly, Diptera: Tephritidae) in 'Hayward' kiwifruit (Actinidia deliciosa (A. Chev.) C.F. Liang and A.R. Ferguson) and 'Zesy002' kiwifruit (Actinidia chinensis Planch.). Experiments on 4 immature life stages (eggs and 3 larval instars) with treatment durations of between 5 and 18 days showed that third instars were the most tolerant to temperatures around 3 °C, with the lethal time to 99.9968% (probit 9) mortality (LT99.9968) estimated to be 17.3 days (95% confidence interval (CI) 16.4-18.2). Larvae reared and treated in 'Zesy002' were significantly more susceptible to cold treatment than those reared in 'Hayward'. A large-scale trial testing a disinfestation protocol of 3 ± 0.5 °C for 18 days treated over 500,000 third-instar C. capitata with no survivors. These results demonstrate that a cold treatment of 3.5 °C or below for 18 days induces C. capitata mortality in kiwifruit at a rate that exceeds 99.9968% with a degree of confidence greater than 99%.

Application of cold argon plasma on germination, root length, and decontamination of soybean cultivars

Applying cold discharge plasma can potentially alter plants' germination characteristics by triggering their physiological activities. As a main crop in many countries, soybean was examined in the present study using cultivars such as Arian, Katoul, Saba, Sari, and Williams in a cold argon plasma. This study has been motivated by the importance of plant production worldwide, considering climate change and the increasing needs of human populations for food. This study was performed to inspect the effect of cold plasma treatment on seed germination and the impact of argon plasma on microbial decontamination was investigated on soybeans. Also, the employed cultivars have not been studied until now the radicals generated from argon were detected by optical emission spectrometry (OES), and a collisional radiative model was used to describe electron density. The germination properties, including final germination percentage (FGP), mean germination time (MGT), root length, and electrical conductivity of biomolecules released from the seeds, were investigated after the plasma treatments for 30, 60, 180, 300, and 420 s. The decontamination effect of the plasma on Aspergillus flavus (A.flavus) and Fusarium solani (F.solani) was also examined. The plasma for 60 s induced a maximum FGP change of 23.12 ± 0.34% and a lowest MGT value of 1.40 ± 0.007 days. Moreover, the ultimate root length was 56.12 ± 2.89%, in the seeds treated for 60 s. The plasma exposure, however, failed to yield a significant enhancement in electrical conductivity, even when the discharge duration was extended to 180 s or longer. Therefore, the plasma duration of 180 s was selected for the blotter technique. Both fungi showed successful sterilization; their infectivity inhibition was 67 ± 4 and 65 ± 3.1%, respectively. In general, the cold plasma used for soybeans in the present study preserved their healthy qualities and reduced the degree of fungal contamination.

The amelioration of salt stress-induced damage in fenugreek through the application of cold plasma and melatonin

Nowadays, it is increasingly crucial to combine innovative approaches with established methods to enhance plant tolerance and maximize the production of beneficial compounds. With this aim in view, a study was carried out to investigate how different melatonin concentrations (0, 30, and 60 ppm), cold plasma treatment (at 3000 and 4000 V), and varying exposure durations (0, 1, 2, and 4 min) affect the physiological and biochemical attributes of fenugreek plants, as well as the levels of diosgenin under salinity stress. This study revealed that the application of 3000 V cold plasma for 2 min with 60 ppm melatonin by establishing cellular redox homeostasis in salinity-treated fenugreek plants, effectively prevented the destruction of pigments and reduced the electrolyte leakage index of malondialdehyde content. The utilization of these two elicitors has the potential to trigger multiple pathways, including the enzymatic and non-enzymatic antioxidants biosynthesis, and abscisic acid-dependent pathways. This activation results in an enhanced production of abscisic acid, auxin, and endogenous melatonin, along with the regulation of signal transduction pathways. Surprisingly, applying these two treatments increased the expression of SQS, CAS, SSR, BGL, SEP, SMT, and diosgenin content by 13, 22.5, 21.6, 19, 15.4, 12, and 6 times respectively. The findings highlight the intricate interplay between these treatments and the positive impact of their combined application, opening up avenues for further research and practical applications in improving plant tolerance to environmental stresses.

Effect of cold plasma treatment and plasma‐activated water on physicochemical and structural properties of starch: A green and novel approach for environmental sustainability

AbstractStarch is a crucial part of the human dietary regimen. Still, its restricted water solubility, low viscosity, and weak heat stability are unfavorable physicochemical characteristics that restrict its use in food applications. So, in the 21st century, green and novel technologies such as cold plasma technology (CPT) and plasma‐activated water (PAW) have been employed for starch modification to improve the starch's physicochemical, digestibility, functional, structural, and thermal properties. This article provided an in‐depth evaluation of the use of cold plasma intervention in starch systems. Moreover, starch was modified due to cross‐linking, plasma etching, and depolymerization mechanisms mediated by plasma species. We may conclude that CPT and PAW are substitute methods for changing starch characteristics.

Evaluating the toxicity of the roots of Asarum heterotropoides var. mandshuricum extracted using the decoction method: Genotoxicity, single-dose toxicity, and 13-week repeated-dose toxicity studies

Ethnopharmacological relevanceThe roots of Asarum heterotropoides F. Maekawa var. mandshuricum F. Maekawa (AR) is a traditional herbal medicine used across Asia, including Korea, China, and Japan. AR exhibits a range of biological activities, such as anti-inflammatory, anti-cancer, cold treatment, and anti-nociceptive effects. Various extraction methods, including decoction, which utilizes traditional knowledge and techniques. The AR decoction extract expected to contain fewer toxicants and have reduced toxicity due to the use of hot water in the extraction process. However, scientific evidence on the toxicity of AR decoction extracts is lacking, necessitating further studies for safe usage. Aim of the studyThis study aimed to evaluate the genotoxicity and toxicity of single and repeated administration of AR decoction extracts. Materials and methodsThe genotoxicity was assessed using a bacterial reverse mutation (Ames test), an in vitro mammalian chromosome aberration test (CA test), and an in vivo micronucleus test (MN test) in Sprague-Dawley (SD) rats. The general toxicity was evaluated through single-dose and 13-week repeated-dose toxicity studies. In the single-dose toxicity study, 40 SD rats were orally administered AR decoction extract at doses of 1000, 2000, and 5000 mg/kg. In the 13-week repeated-dose toxicity study, 140 SD rats received daily oral doses of 0, 250, 500, 1000, 2000, and 5000 mg/kg of AR decoction extract. ResultsThe genotoxicity tests revealed that AR decoction extract was not genotoxic. The single-dose toxicity study showed no changes in body weight, clinical pathology, or macroscopic findings, with the approximate lethal dose (ALD) exceeding 5000 mg/kg. The 13-week repeated-dose toxicity study demonstrated no treatment-related changes in body weight, general symptoms, hematology, clinical chemistry, or urinalysis. Histopathological findings revealed hyperplasia of squamous cells in the forestomach after AR decoction extract administration, a treatment-related effect that resolved during the recovery period. The no observed adverse effect level (NOAEL) for both male and female rats was estimated to be 2000 mg/kg. ConclusionsThis study establishes the non-toxic dose of AR decoction extract, providing a foundation for further non-clinical and clinical evaluations AR safety.

Arc plasma for high-efficiency ionization and scavenging of plasticizers in wrap films

Herein, ambient electric arc ionization mass spectrometry was used to examine 16 plasticizers in various wrap films, demonstrating high sensitivity (detection limit: <0.2 ng/mg) and precision (intra-/inter-day precision: <12 %). The ease of operation helps in the identification of wrap film and plasticizer analysis. In addition, the introduction of a cold arc plasma treatment presents a practical and innovative method for effectively eliminating plasticizers. This innovative strategy has implications for both environmental protection and food safety.

Impact of cold plasma on pearl and barnyard millets' microbial quality, antioxidant status, and nutritional composition

In the quest for sustainable and innovative food processing technologies, cold plasma treatment has emerged as a promising approach with the potential to enhance grains' nutritional and functional properties. This study investigates the impact of cold plasma treatment on two millet varieties, namely pearl millet (Pennisetum glaucum) and barnyard millet (Echinochloa spp.). This study analyzed the effect of Cold plasma on the proximate composition, vitamin content, physiochemical property, anti-nutrient factor, bioactive compounds, antioxidant activity and microbial count of millets. Pearl millet (RP) and Barnyard millet (RB) (native), cold plasma treated Pearl (CP) and Barnyard (CB) (2 kV, 5 min) were characterized. A noticeable change was found in fat, vitamin B-complex content and antioxidant activity. Furthermore, the microbial count analysis revealed that cold plasma treatment induced substantial reductions in bacterial and yeast populations, underscoring the technology's effectiveness in enhancing the safety and extending the shelf-life of millet grains. Treatments of samples led to a reduction of phytic acid and tannin. In pearl millet, tannin content decreased by 18%, and phytic acid content was reduced by 57%. In barnyard millet, there was a substantial (24%) reduction in tannin content and a 61% decrease in phytic acid. Total Flavonoid content (TFC) and Total Phenolic content (TPC) also decreased after treatment. But this treatment led to an increase in fat content by 43% and 87% in CP and CB, respectively. These alterations offer new insights into the potential of cold plasma treatment as a means to enhance the nutritional quality and safety of millets. The results of this study contribute to the growing body of knowledge on innovative food processing techniques for improving the nutritional value of grains.

Cold plasma treatment boosts barley germination and seedling vigor: Insights into soluble sugar, starch, and protein modifications

This study investigates the impact of three cold plasma treatments on barley seed germination: direct treatment of dry seeds (DDS), direct treatment of water-soaked seeds (DWS), and indirect treatment of seeds using plasma-activated water (IPAW). Our findings reveal that while DDS maintained the seed's imbibition structures, DWS significantly reduced water uptake. Notably, DWS-treated seeds exhibited a substantial increase in moisture content, potentially leading to an oxygen-deficient environment within the seed. This condition appeared to hinder germination, contrasting with the beneficial effects observed in DDS-treated seeds. Analyses of surface hydrophilicity, phenolic compounds, carbohydrate composition, protein storage and seedling growth were conducted. Interestingly, cold plasma treatment enhanced seed surface hydrophilicity, as evidenced by a decrease in water contact angles, particularly for DWS. We observed specific reductions in flavonoids and total phenolics, alongside shifts in carbohydrate composition, including increased sugar content up to 15.1% (DDS) and 13.5% (DWS), accompanied by a decrease in starch content to 189.00 ± 7.86 mg/g FM for DWS. Protein storage assessments revealed declines in albumin, globulin and prolamin fractions post-CP exposure. Finally, DDS and IPAW treatments markedly improved seedling shoot growth (from two to three-fold), underscoring the potential of these treatments in enhancing barley germination.

A transcriptional regulation of ERF15 contributes to ABA-mediated cold tolerance in tomato.

Cold stress is a major meteorological threat to crop growth and yield. Abscisic acid (ABA) plays important roles in plant cold tolerance by activating the expression of cold-responsive genes; however, the underlying transcriptional regulatory module remains unknown. Here, we demonstrated that the cold- and ABA-responsive transcription factor ETHYLENE RESPONSE FACTOR 15 (ERF15) positively regulates ABA-mediated cold tolerance in tomato. Exogenous ABA treatment significantly enhanced cold tolerance in wild-type tomato plants but failed to rescue erf15 mutants from cold stress. Transcriptome analysis showed that ERF15 was associated with the expression of cold-responsive transcription factors such as CBF1 and WRKY6. Further RT-qPCR assays confirmed that the ABA-induced increased in CBF1 and WRKY6 transcripts was suppressed in erf15 mutants when the plants were subjected to cold treatment. Moreover, yeast one-hybrid assays, dual-luciferase assays and electrophoretic mobility shift assays demonstrated that ERF15 activated the transcription of CBF1 and WRKY6 by binding their promoters. Silencing CBF1 or WRKY6 significantly decreased cold tolerance. Overall, our study identified the role of ERF15 in conferring ABA-mediated cold tolerance in tomato plants by activating CBF1 and WRKY6 expression. This study not only broadens our knowledge of the mechanism of ABA-mediated cold tolerance in plants but also highlights ERF15 as an ideal target gene for cold-tolerant crop breeding.