Antioxidant and enzymatic responses to oxidative stress induced by pre-harvest water supply reduction and ripening on mango (Mangifera indica L. cv. 'Cogshall') in relation to carotenoid content

Bioactive Compound Diversity in a Wide Panel of Sweet Potato (Ipomoea batatas L.) Cultivars: A Resource for Nutritional Food Development

OBJECTIVES

This study provides an overview of the composition of the raw root flesh of a panel of 22 sweet potato (Ipomoea batatas L.) cultivars, with a focus on bioactive compounds. The large diversity of the proximate and phytochemical compositions observed between cultivars and within and between different flesh colors pointed out the importance of composition analysis and not only color choice for the design of foods with nutritional benefits.

METHODS

The nutritional composition (starch, protein, total dietary fibers) and bioactive compound composition of 22 cultivars from Reunion Island, maintained in the Vatel Biological Resource Center, were investigated.

RESULTS

Orange and purple cultivars stood out from white and yellow cultivars for their higher nutritional composition. Purple sweet potatoes were notable for their high contents of anthocyanins (55.7 to 143.4 mg/g dry weight (DW)) and phenolic compounds, in particular chlorogenic acid and ferulic acid, contributing to antioxidant activities, as well as their fiber content (14.1 ± 2.1% DW). Orange cultivars were rich in β-carotene (47.2 ± 0.7 mg/100 g DW) and to a lesser extent α-carotene (4.8 ± 1.2 mg/100 g DW). In contrast, certain white cultivars demonstrated suboptimal nutritional properties, rendering them less relevant even for applications where the lack of coloration in food is desired.

CONCLUSIONS

Those characteristics enable the selection of sweet potato varieties to design food products ensuring optimal nutritional benefits and culinary versatility.

Evaluation of the Effectiveness of Innovative Sorbents in Restoring Enzymatic Activity of Soil Contaminated with Bisphenol A (BPA)

As part of the multifaceted strategies developed to shape the common environmental policy, considerable attention is now being paid to assessing the degree of environmental degradation in soil under xenobiotic pressure. Bisphenol A (BPA) has only been marginally investigated in this ecosystem context. Therefore, research was carried out to determine the biochemical properties of soils contaminated with BPA at two levels of contamination: 500 mg and 1000 mg BPA kg-1 d.m. of soil. Reliable biochemical indicators of soil changes, whose activity was determined in the pot experiment conducted, were used: dehydrogenases, catalase, urease, acid phosphatase, alkaline phosphatase, arylsulfatase, and β-glucosidase. Using the definition of soil health as the ability to promote plant growth, the influence of BPA on the growth and development of Zea mays, a plant used for energy production, was also tested. As well as the biomass of aerial parts and roots, the leaf greenness index (SPAD) of Zea mays was also assessed. A key aspect of the research was to identify those of the six remediating substances-molecular sieve, zeolite, sepiolite, starch, grass compost, and fermented bark-whose use could become common practice in both environmental protection and agriculture. Exposure to BPA revealed the highest sensitivity of dehydrogenases, urease, and acid phosphatase and the lowest sensitivity of alkaline phosphatase and catalase to this phenolic compound. The enzyme response generated a reduction in the biochemical fertility index (BA21) of 64% (500 mg BPA) and 70% (1000 mg BPA kg-1 d.m. of soil). The toxicity of BPA led to a drastic reduction in root biomass and consequently in the aerial parts of Zea mays. Compost and molecular sieve proved to be the most effective in mitigating the negative effect of the xenobiotic on the parameters discussed. The results obtained are the first research step in the search for further substances with bioremediation potential against both soil and plants under BPA pressure.

Impact of Water Supply Reduction and Cold Storage on Phenolic Compounds from Mango (Mangifera indica L. cv. Cogshall) Pulp and Peel

The impacts of water supply reduction and cold storage were investigated on the peels and pulps of cv. Cogshall mangoes, regarding their phenolic compound contents. Phenolics identification was operated using HPLC-MSn for both compartments revealing an unbalanced repartition. Peels had a richer and more complex profile, counting xanthone glycoside (mangiferin), flavonoids (quercetin, kaempferol) and majorly gallotannins. Pulps presented smaller amounts of phenolics and a simpler profile majorly represented by gallotannins and gallic acid derivatives. During fruit ripening, the phenolic contents decreased in both compartments, but faster in the pulp. This behavior can be attributed to the oxidative stress observed in mango pulp during ripening. Cutting down the water supply during the fruit growth triggered an increase in phenolic contents of both the peels and pulp of mango fruits. This increase affected all compounds. Cold storage at 12 or 7 °C led to an increase in mangiferin and flavonoids contents in the fruit peel, interpreted as a stress-response reaction.

Aloe vera gel coating delays softening and maintains quality of stored persimmon (Diospyros kaki Thunb.) Fruits

The effect of Aloe vera (AV) gel coating was studied on antioxidant enzymes activities, oxidative stress, softening and associated quality attributes of persimmon fruits. The fruits were coated with 0 and 50% AV-gel coating and stored for 20 days at 20 ± 1 ºC. AV-gel coated fruits exhibited considerably less weight loss, hydrogen peroxide level, electrolyte leakage and malondialdehyde content. AV-gel coated fruits had significantly higher ascorbate peroxidase, peroxidase, superoxide dismutase and catalase activities. In addition, AV-gel coating suppressed pectin methylesterase, polygalacturonase and cellulase activities and showed higher ascorbic acid, DPPH scavenging antioxidants and phenolics, and lower sugars and carotenoids. To the best of our knowledge, these results are the first evidence that AV-gel coating modulates the activities of cell wall degrading enzymes to delay ripening in climacteric fruits. So, AV-gel coating prohibited the onset of senescence by activating enzymatic antioxidant system, accumulating bioactive compounds and suppressing cell wall degradation.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-022-05412-5.

Metabolomics-Based Evaluation of Crop Quality Changes as a Consequence of Climate Change

Fruit composition determines the fruit quality and, consequently, consumer acceptance. As fruit quality can be modified by environmental conditions, it will be impacted by future alterations produced by global warming. Therefore, agricultural activities will be influenced by the changes in climatological conditions in cultivable areas, which could have a high socioeconomic impact if fruit production and quality decline. Currently, different stresses are being applied to several cultivated species to evaluate their impact on fruit metabolism and plant performance. With the use of metabolomic tools, these changes can be precisely measured, allowing us to determine changes in the patterns of individual compounds. As these changes depend on both the stress severity and the specific species involved and even on the specific cultivar, individual analysis must be conducted. To date, the most-studied crops have mainly been crops that are widely cultivated and have a high socioeconomic impact. In the near future, with the development of these metabolomic strategies, their implementation will be extended to other species, which will allow the adaptation of cultivation conditions and the development of varieties with high adaptability to climatological changes.

Phytotoxicity and Effect of Ionic Liquids on Antioxidant Parameters in Spring Barley Seedlings: The Impact of Exposure Time

The influence of the ionic liquids (ILs) tetrabutylammonium bromide [TBA][Br], 1-butyl-3-methylimidazole bromide [BMIM][Br], and tetrabutylphosphonium bromide [TBP][Br] added at different concentrations to the soil were studied for the growth and development of spring barley seedlings. Samples were harvested at three different time points: day 7, 14, and 21 after addition of ILs. The results show that [TBP][Br] was the most toxic. The introduction of this IL at the dose of 100 mg kg−1 of soil DM decreased the growth of seedlings at all test dates. The addition of the studied ILs to the soil in higher doses resulted in an increase in peroxidase and catalase activity, which may indicate the occurrence of oxidative stress in plants. An increase in the content of plant dry matter weight, contents of H2O2 and proline and a decrease in the content of photosynthetic pigments in barley seedlings were also observed. The malondialdehyde content and superoxide dismutase activity fluctuated randomly during the experiment. As a result, it was found that the phytotoxicity of ILs and the magnitude of oxidative stress in seedlings depended more on the added doses of these compounds than on the measurement date.

Superoxide Radical Metabolism in Sweet Pepper (Capsicum annuum L.) Fruits Is Regulated by Ripening and by a NO-Enriched Environment

Superoxide radical (O2 •-) is involved in numerous physiological and stress processes in higher plants. Fruit ripening encompasses degradative and biosynthetic pathways including reactive oxygen and nitrogen species. With the use of sweet pepper (Capsicum annuum L.) fruits at different ripening stages and under a nitric oxide (NO)-enriched environment, the metabolism of O2 •- was evaluated at biochemical and molecular levels considering the O2 •- generation by a NADPH oxidase system and its dismutation by superoxide dismutase (SOD). At the biochemical level, seven O2 •--generating NADPH-dependent oxidase isozymes [also called respiratory burst oxidase homologs (RBOHs) I-VII], with different electrophoretic mobility and abundance, were detected considering all ripening stages from green to red fruits and NO environment. Globally, this system was gradually increased from green to red stage with a maximum of approximately 2.4-fold increase in red fruit compared with green fruit. Significantly, breaking-point (BP) fruits with and without NO treatment both showed intermediate values between those observed in green and red peppers, although the value in NO-treated fruits was lower than in BP untreated fruits. The O2 •--generating NADPH oxidase isozymes I and VI were the most affected. On the other hand, four SOD isozymes were identified by non-denaturing electrophoresis: one Mn-SOD, one Fe-SOD, and two CuZn-SODs. However, none of these SOD isozymes showed any significant change during the ripening from green to red fruits or under NO treatment. In contrast, at the molecular level, both RNA-sequencing and real-time quantitative PCR analyses revealed different patterns with downregulation of four genes RBOH A, C, D, and E during pepper fruit ripening. On the contrary, it was found out the upregulation of a Mn-SOD gene in the ripening transition from immature green to red ripe stages, whereas a Fe-SOD gene was downregulated. In summary, the data reveal a contradictory behavior between activity and gene expression of the enzymes involved in the metabolism of O2 •- during the ripening of pepper fruit. However, it could be concluded that the prevalence and regulation of the O2 •- generation system (NADPH oxidase-like) seem to be essential for an appropriate control of the pepper fruit ripening, which, additionally, is modulated in the presence of a NO-enriched environment.

Daily Dietary Antioxidant Interactions Are Due to Not Only the Quantity but Also the Ratios of Hydrophilic and Lipophilic Phytochemicals

The hydrophilic extracts of mulberry (HEM) and blueberry (HEB) and lipophilic extracts of mango (LEM) and watermelon (LEW) were mixed in different ratios to assess the antioxidant interactions by chemical-based (DPPH and ABTS assays) and H9c2 cell-based models. There were both synergistic and antagonistic antioxidant interactions among these fruits. Some groups with combinational extracts showed stronger synergistic antioxidant effects than the individual groups, and others (HEM-LEW F1/10, LEW-LEM F5/10, and HEB-LEM F3/10) showed stronger antagonistic effects than the individual groups based on the indicators [the values of DPPH, ABTS, and MTT; the expression of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), and malondialdehyde (MDA); the release of lactate dehydrogenase (LDH); and the quantification of cellular antioxidant activity]. The principal component analysis (PCA) showed that samples could be defined by two principal components: PC1, the main phenolic acids and anthocyanins, and PC2, carotenoids. From our results, primarily, carotenoids were in the majority in antagonistic groups, and phenolics and anthocyanins were in the majority in synergistic groups. However, the combinational groups containing only hydrophilic compounds did not always show synergistic effects. Therefore, the compatibility of diets indicates balancing the ratios of hydrophilic and lipophlic compounds in our daily food. In addition, the expression of enzymes (SOD, GSH-Px, and CAT) may not be sensitive to the changes of antioxidant activity caused by the combinations with different ratios of hydrophilic and lipophilc compounds. The different structures of lipophilic compounds (β-carotene and lycopene) could influence the antagonistic effects.

Transcriptome, cytological and biochemical analysis of cytoplasmic male sterility and maintainer line in CMS-D8 cotton

Key message This research based on RNA-seq, biochemical, and cytological analyses sheds that ROS may serve as important signaling molecules of cytoplasmic male sterility in CMS-D8 cotton. To understand the mechanism of cytoplasmic male sterility in cotton (Gossypium hirsutum), transcriptomic, cytological, and biochemical analysis were performed between the cytoplasmic male sterility CMS-D8 line, Zhong41A, and its maintainer line Zhong41B. A total of 2335 differentially expressed genes (DEGs) were identified in the CMS line at three different stages of anther development. Bioinformatics analysis of these DEGs indicated their relationship to reactive oxygen species (ROS) homeostasis, including reduction-oxidation reactions and the metabolism of glutathione and ascorbate. At the same time, DEGs associated with tapetum development, especially the transition to secretory tapetum, were down-regulated in the CMS line. Biochemical analysis indicated that the ability of the CMS line to eliminate ROS was decreased, which led to the rapid release of H₂O₂. Cytological analysis revealed that the most crucial defect in the CMS line was the abnormal tapetum. All these results are consistent with the RNA sequencing data. On the basis of our findings, we propose that ROS act as signal molecules, which are released from mitochondria and transferred to the nucleus, triggering the formation of abnormal tapetum.

Role of cation structure in the phytotoxicity of ionic liquids: growth inhibition and oxidative stress in spring barley and common radish

The present study determines the influence of three ionic liquids (ILs) containing cations with diversified structure on the growth and development of spring barley seedlings and common radish leaves. Increasing amounts of 1-butyl-1-methylpyrrolidinium hexafluorophosphate [Pyrrol][PF₆], 1-butyl-1-methylpiperidinium hexafluorophosphate [Piper][PF₆], and 1-butyl-4-methylpyridinium hexafluorophosphate [Pyrid][PF₆] were added to the soil on which both plants were cultivated. The results of this studies showed that the applied ILs were highly toxic for plants, demonstrated by the inhibition of length of plant shoots and roots, decrease of fresh mass, and increase of dry weight content. Common radish turned out to be the plant with higher resistance to the used ILs. The differences in the cation structure did not influence phytotoxity of ILs for spring barley. Furthermore, all ILs led to a decrease of photosynthetic pigments, which was directly followed by decreased primary production in plants. Oxidative stress in plants occurred due to the presence of ILs in the soil, which was demonstrated by the increase of malondialdehyde (MDA) content, changes in the H₂O₂ level, and antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD). The changes in the chlorophyll contents and the increase of POD activity turned out to be the most significant oxidative stress biomarkers in spring barley and common radish. Both spring barley and radish exposed to ILs accumulated a large amount of fluoride ion.

Changes in growth and physiological parameters of spring barley and common radish under the influence of 1-butyl-2,3-dimethylimidazolium tetrafluoroborate

Ionic liquids (ILs) constitute a large group of chemical substances, which, thanks to their desirable properties, still attract attention of scientists and representatives of the industry. This may lead to a greater commercial use of these compounds, which will undoubtedly lead to the contamination of soils, constituting the basis of plant vegetation, with these substances. This paper presents effect of 1-butyl-2,3-dimethylimidazolium tetrafluoroborate [BMMIM][BF₄] on the growth and development of spring barley and common radish and on the physiological and biochemical changes in these plants. The used IL was characterized by relatively high toxicity for the monocotyledonous plant, which was exhibited by shortening of the plant length and their root length, decreasing the fresh weight yield. Moreover, [BMMIM][BF₄] led to the decrease in the content of all photosynthetic pigments in spring barley seedlings, reflecting the decrease in the fresh yield. Furthermore, the increase of malondialdehyde (MDA) level and changes in contents of hydrogen peroxide (H₂O₂) and the activity of antioxidant enzymes, that is, superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) may suggest the occurrence of oxidative stress in spring barley. The decrease in the content of photosynthetic pigment and the increase of POD activity constitute the most reliable markers of oxidative stress and, at the same time, the signs of early aging of spring barley plants. Common radish was the plant with a very high tolerance for the used IL, which can be indicated by, that is, EC₅₀ values, determined based on inhibition of root length, plant length, and fresh weight yield.

Growth inhibition and efficiency of the antioxidant system in spring barley and common radish grown on soil polluted ionic liquids with iodide anions

Ionic liquids (ILs) constitute a huge group of substances that are increasingly common in the commercial use. This situation may lead to the contamination of the soil environment which being the basic of plants vegetation. This paper presents the effect of four ILs with I^- anion on the growth and development of spring barley (Hordeum vulgare) and common radish (Raphanus sativus L. subvar. radicula Pers) and changes in metabolism of the plants. Seedlings of spring barley and common radish cultivated on soil with increasing ILs concentration exhibited typical phytotoxicity symptoms. A considerable reduction of shoot and root lengths, decrease of fresh weight (FW) and increase of dry weight (DW) occurred in both test plants. Ionic liquids concentration increase in soil was correlated with the decrease of concentrations of all photosynthetic pigments in the plants. The observed increase of malondialdehyde (MDA) concentration and changes in the H₂O₂ level indicated presence of oxidative stress in spring barley and common radish, which usually led to the increase of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) activity. The most reliable biomarker of oxidative stress was chlorophyll level and changes in POD activity.

The effect of the number of alkyl substituents on imidazolium ionic liquids phytotoxicity and oxidative stress in spring barley and common radish seedlings

Increasing amounts of two ILs: 1-butyl-3-methylimidazolium hexafluorophosphate [BMIM][PF₆] and 1-butyl-2,3-dimethylimidazolium hexafluorophosphate [BMMIM][PF₆], were introduced to soil in which spring barley (Hordeum vulgare) and common radish (Raphanus sativus L. subvar. radicula Pers.) seedlings were cultivated, in order to evaluate the phytotoxicity of ionic liquids with imidazolium cation with two or three alkyl substituents attached. The results of the study i.e. the inhibition of the length of plants and their roots, as well as the yield of fresh weight of plants, clearly showed that differences in the number of substituents did not affect the toxicity of these ILs. Although, radish was more resistant to the applied ionic liquids than barley. Ionic liquids led to a decrease in the content of all assimilation pigments and induced oxidative stress in the plants, as showed by an increase in malondialdehyde (MDA) content, and changes in the level of H₂O₂ and antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD). The best biomarkers of oxidative stress in both plants were the changes in chlorophyll content and the increase in POD activity. Both spring barley and radish exposed to [BMIM][PF₆] and [BMMIM][PF₆] accumulated a large amount of fluoride ions, which further increased the toxicity of these compounds for both plants.

Oxidative stress in spring barley and common radish exposed to quaternary ammonium salts with hexafluorophosphate anion

Quaternary ammonium salts (QAS), including ionic liquids (ILs), constitute a huge group of substances, which due to their desirable physical and chemical properties still attracts great interest in many industrial sectors. An increased concentration of this compound in the environment may lead to the contamination of the natural environment and may pose a potential threat to all organisms, including terrestrial higher plants. The present study demonstrates the interaction of three QAS with PF6(-) anions - tetramethylammonium [TMA][PF6], tetrabutylammonium [TBA][PF6], and tetrahexylammonium [THA][PF6] hexafluorophosphates - and its impact on the physiological and biochemical changes in spring barley seedlings and common radish plants. A similar study was also carried out by introducing the inorganic salt - ammonium hexafluorophosphate [A][PF6] to the soil; the results showed the soil became highly toxic to both plants. All the salts used led to significant changes in the metabolism of both spring barley and common radish which can be evidenced, for example, by a decrease in the content of chlorophyll a (Chla), chlorophyll b (Chlb), and total chlorophyll (Chla + b), as well as carotenoids (Car). The decrease in assimilation pigments was linearly correlated with an increasing concentration of QAS in the soil. QAS and [A][PF6] led to the formation of oxidative stress in both experimental plants, as evidenced by an increase in malondialdehyde (MDA) content in their cells and the changes in H2O2 level. In response to stress, the plants synthesized enzymatic free radicals (ROS) scavengers that lead to changes in the activity of superoxide dismutase (SOD) and catalase (CAT), as well as significantly increased peroxidase (POD) activity. A decrease in the content of assimilation pigments and an increased POD activity are the most reliable indices of oxidative stress, and concurrently the signs of premature plants aging. Common radish proved to be more resistant to the presence of QAS in the soil compared to spring barley.