Edible Plant Parts Research Articles

Dietary fiber ameliorates lead-induced gut microbiota disturbance and alleviates neuroinflammation.

Dietary fiber (DF) is a carbohydrate from the edible part of plants and has the functions of promoting gastrointestinal motility, regulating gut microbiota (GM) and improving health. Lead is a non-essential toxic heavy metal that can accumulate in the environment over time and enter the body through the respiratory tract, skin and gastrointestinal tract. Lead not only causes disturbances in GM but also leads to loss of homeostasis of immune functions, causes neuronal damage and results in neuroinflammation. The scientific literature has reported that DF had anti-inflammatory activity as a natural product. This review highlights the role of DF and its metabolic products in alleviating lead-induced neuroinflammation by inducing changes in the species and quantity of GM and regulating the immune system, providing a potential dietary protective strategy for lead-induced disease. © 2022 Society of Chemical Industry.

Immobilization of hexavalent chromium in soil-plant environment using calcium silicate hydrate synthesized from coal gangue

The presence of excessive hexavalent chromium (Cr(VI)) in the contaminated soils and plants has become a global environmental issue due to its toxicity and carcinogenicity. This work investigated the feasibility of immobilizing Cr(VI) in the soil-plant environment using calcium silicate hydrate (C–S–H) synthesized from coal gangue. The results revealed that the C–S–H amendment increased soil pH and organic matter (OM), which further promoted Cr(VI) immobilization. Results also revealed that exchangeable and carbonate bound fractions of Cr were either converted into Fe/Mn oxide and OM bound fractions of Cr or hardly released residual fraction of Cr due to C–S–H treatment. The C–S–H accelerated conversion of Cr(VI) into Cr(III) promoting plant growth and alleviating the toxic effect of Cr(VI). Cr(VI) was mainly immobilized and accumulated in the plant roots which resulted in comparatively lower Cr(VI) content in the edible part of plants. The exchangeable fraction of Cr in soil could be used as a bioavailability evaluation index of Cr(VI) in plants. In short, C–S–H was proved to be a practical and environmentally friendly amendment for in-situ immobilization of Cr(VI) contaminated soil.

Flavonoids a Bioactive Compound from Medicinal Plants and Its Therapeutic Applications.

Plants generally secrete secondary metabolites in response to stress. These secondary metabolites are very useful for humankind as they possess a wide range of therapeutic activities. Secondary metabolites produced by plants include alkaloids, flavonoids, terpenoids, and steroids. Flavonoids are one of the classes of secondary metabolites of plants found mainly in edible plant parts such as fruits, vegetables, stems, grains, and bark. They are synthesized by the phenylpropanoid pathway. Flavonoids possess antibacterial, antiviral, antioxidant, anti-inflammatory, antimutagenic, and anticarcinogenic properties. Due to their various therapeutic applications, various pharmaceutical companies have exploited different plants for the production of flavonoids. To overcome this situation, various biotechnological strategies have been incorporated to improve the production of different types of flavonoids. In this review, we have highlighted the various types of flavonoids, their biosynthesis, properties, and different strategies to enhance the production of flavonoids.

Reducing cadmium bioaccumulation in Theobroma cacao using biochar: basis for scaling-up to field

The intake of Cd-enriched food is the main Cd pathway for the nonsmoking population. In some cases, Cd bioaccumulates in edible plant parts which comprise risk to consumers, because of Cd is a harmful heavy metal that can cause potent environmental and health hazards. For instance, Cd enrichment of cacao seeds have led to Cd enrichment of cacao-based products. In Latin America and the Caribbean, Cd bioaccumulation in cacao seeds occurs in different regions with diverse edaphoclimatic conditions, which makes it difficult to select soil remediation alternatives. Limited resources require that potential amendments must be carefully investigated through laboratory and/or greenhouse conditions before scaling up to field experiments. In this study, we evaluated the effectiveness of four biochars: coffee-, quinoa-, and inoculated- and palm-biochar, derived from three feedstocks: coffee husk, quinoa straw, and oil palm residues, respectively. Biochars were applied in two rates (1 and 2% w/w) in two soils, one moderately acidic and one slightly alkaline (Cd-spiked and non-spiked). CCN-51 cacao plants were used for the greenhouse experiment. After 130 days, biometric parameters, the bioavailability of Cd in the soil, and the concentration of Cd and mineral nutrients in the plants were measured. Quinoa biochar at the 2% significantly decreased (P < 0.01), by ∼71%, bioavailable Cd in moderately acidic and slightly alkaline soils, and leaf-Cd by ∼48%. Soil pH, electrical conductivity, and effective cation exchange capacity were significantly (P < 0.01) correlated with bioavailable soil and leaf-Cd. Biochar characteristics, such as ash contents, basic cations content, and surface functional groups could be used as indicators for the selection of biochars to reduce Cd uptake by cacao. Additionally, application of quinoa derived biochar provided P and K, which could increase productivity to offset mitigation costs. Overall, incorporation of quinoa biochar at 2% rate is effective for lowering bioavailable Cd in different soil types which reduces leaf-Cd in cacao plants.

Possible explanation for limited reduction of pathogens on radish microgreens after spray application of chlorinated water during growth with disperse contamination spread of abiotic surrogate on leaves

AbstractThe purpose of this study was to determine the efficacy of spray application of chlorinated water before harvest on the population of Salmonella enterica Typhimurium and Escherichia coli O157:H7 on radish microgreens. The transfer of abiotic surrogate to radish microgreens was also evaluated to track possible pathogen contamination spread by inoculating seed and growth media. During growth, microgreens inoculated with strains of pathogens were sprayed with chlorinated water at three different concentrations (0.50, 1.00, and 2.00 ± 0.05 ppm free chlorine). Spray application of chlorinated water was performed on microgreens once (day 9), twice (day 8 and 9), three (day 7, 8, and 9), and four times (day 6, 7, 8, and 9). Microgreens were harvested 12 hr after the last application of chlorinated water. Salmonella and E. coli O157:H7 populations were reduced with the increase in chlorine concentration. Chlorinated water reduced Salmonella and E. coli O157:H7 populations up to 1.1 log CFU/g (p &lt; .05) and 0.9 log CFU/g (p &gt; .05), respectively. Images taken under UV illumination provided the visualization of abiotic surrogate spread on cotyledon and upper hypocotyl (all edible parts) of radish microgreen plants regardless of seed or growth media inoculation. Scanning Electron Microscopy showed the presence of abiotic surrogate and generic E. coli on microgreen leaves. Spray application of chlorinated water during microgreen growth may help to reduce microbial load but cannot be used as the only control measure.

Emerging trends of edible vaccine therapy for combating human diseases especially COVID-19: Pros, cons, and future challenges.

The researchers are still doing efforts to develop an effective, reliable, and easily accessible vaccine candidate to protect against COVID‐19. As of the August 2020, nearly 30 conventional vaccines have been emerged in clinical trials, and more than 200 vaccines are in various development stages. Nowadays, plants are also considered as a potential source for the production of monoclonal antibodies, vaccines, drugs, immunomodulatory proteins, as well as used as bioreactors or factories for their bulk production. The scientific evidences enlighten that plants are the rich source of oral vaccines, which can be given either by eating the edible parts of plants and/or by oral administration of highly refined proteins. The use of plant‐based edible vaccines is an emerging trend as it possesses minimum or no side effects compared with synthetic vaccines. This review article gives insights into different types of vaccines, the use of edible vaccines, advantages of edible vaccines over conventional vaccines, and mechanism of action of edible vaccines. This review article also focuses on the applications of edible vaccines in wide‐range of human diseases especially against COVID‐19 with emphasis on future perspectives of the use of edible vaccines.

Revisiting the mechanisms of arsenic uptake, transport and detoxification in plants

Arsenic (As) contamination leading to toxicity in animals and humans has become a major concern in the last few decades. Chronic exposure to As occurs either through contaminated drinking water or food chain. Introduction of As in the food chain takes place by its excessive uptake from soil by plants due to the irrigation with As contaminated water. The major source of human exposure to As is through consumption of As-accumulating crops and vegetables. Arsenic taken up by the plants is translocated and accumulated in the edible plant parts making it a serious worldwide concern to take necessary steps. Developing plants with reduced As levels in their edible parts is the most plausible strategy for decreasing human As intake, which requires understanding the mechanism of As uptake from soil and its transport to the above ground tissues of plants. The present review sums up the recent progress made in understanding the As uptake, translocation and detoxification mechanisms in plants, underlining the role of transporters involved in these processes. Therefore, the expressions of the candidate genes for As uptake, translocation and detoxification has been analyzed under different developmental stages and tissues of model plant rice from publicly available microarray data. The review also summarized the biotechnological approaches for manipulation of As uptake, transport and tolerance associated genes to enhance As tolerance in different plant species. Overall, the review provides a comprehensive understanding of the potential strategies for lower As accumulation in plants to eliminate the As toxicity in human.

Auxin Response Factors Are Ubiquitous in Plant Growth and Development, and Involved in Crosstalk between Plant Hormones: A Review

Auxin response factors (ARFs) are an important family of transcription factors involved in the exertion of auxin in plants and play a key role in regulating the growth and development of plant nutritional and reproductive organs such as roots, stems, leaves, flowers, fruits, and seeds. Foods of plant origin occupy an important place in the nutritional structure of the human diet, and the main edible parts of different plants vary. In this paper, we review recent research reports on ARFs and summarize its role in the regulation of leaf, flower, root, and fruit growth, as well as other important life activities. We also present the challenges and opportunities that ARFs will present in the future. It will be important to deepen our understanding of the mechanisms by which ARFs interact with other proteins or genes. In addition, it is worth considering that more technical tools should be put into the study of ARFs and that the research should be oriented towards solving practical problems. In the future, it is expected that the nutrition and function of plant-derived foods can be improved through gene editing and other means.

Zinc and iron application in conjunction with nitrogen for agronomic biofortification of field crops – a review

Context Maintaining food and nutritional security for the ever increasing population of the world is a great chllenge. Zinc and iron are important micronutrients for both human health and plant growth. Insufficient intake of these micronutrients leads to their deficiency in human body which causes morbidity and mortality in different age groups of poor populations in developing countries. Aims Therefore, agronomic biofortification is considered the most promising approach to alleviate zinc and iron malnutrition in developing countries. Methods The studies reviewed in this article clearly show that the combined application of zinc and nitrogen, iron and nitrogen, and zinc, iron and nitrogen to the soil or to the foliage during the reproductive phase leads to enhanced nutrient (zinc and iron) content in edible parts of crop plants. This happens as the remobilisation and translocation of zinc, iron and urea are governed by the same genetic pathways inside the plant. Key results The soil/foliar application of micronutrients (zinc and iron) along with nitrogen (mainly through urea) improves not only the micronutrient (zinc and iron) content in edible parts of the crop plants but also the crop productivity, and thus, is a win–win situation for growers as well as consumers. Conclusions Foliar application of urea at 1–2% along with zinc or iron or both during the reproductive phase has been found more effective for biofortification point of view. Implications This article reviews the effects of zinc and iron application in combination with nitrogen on agronomic biofortification in important field crops.

Ethnobotanical Study of Wild Edible Plants and Their Indigenous Knowledge in Sedie Muja District, South Gondar Zone, Northwestern Ethiopia

Wild edible plants have played a vital role in supplementing the diet of people in developing countries. People in Sedie Muja District, South Gondar Zone, consume different parts of wild plants. This study was done in Sedie Muja District, South Gondar Zone to deal with ethnobotanical uses of selected wild edible plants. Field surveys were carried out in 2018-2019. Ethnobotanical data were collected from 84 respondents using semi-structured interview, guided field walk, market survey and field observations. Preference ranking, direct matrix ranking and informant consensus with buyers, sellers, cookers and elderly people of the user groups were used for data analysis. A total of 33 wild edible plants were documented. Of these families, Moraceae, Fabaceae and Solanaceae were the most dominant families that account 3 (11.5%) species each. Fruits are the most edible parts compared to the other edible plant parts that account 18 (54.5%). These species can be promoted for large-scale cultivation and marketing for the benefit of the local communities.

Dietary fiber in plant cell walls—the healthy carbohydrates

Abstract Dietary fiber (DF) is one of the major classes of nutrients for humans. It is widely distributed in the edible parts of natural plants, with the cell wall being the main DF-containing structure. DF content varies significantly in different plant species and organs, and the processing procedure can have a dramatic effect on the DF composition of plant-based foods. Given the considerable nutritional value of DF, a deeper understanding of DF in food plants, including its composition and biosynthesis, is fundamental to the establishment of a daily intake reference of DF and is also critical to molecular breeding programs for modifying DF content. In the past decades, plant cell wall biology has seen dramatic progress, and such knowledge is of great potential to be translated into DF-related food science research and may provide future research directions for improving the health benefits of food crops. In this review, to spark interdisciplinary discussions between food science researchers and plant cell wall biologists, we focus on a specific category of DF—cell wall carbohydrates. We first summarize the content and composition of carbohydrate DF in various plant-based foods, and then discuss the structure and biosynthesis mechanism of each carbohydrate DF category, in particular the respective biosynthetic enzymes. Health impacts of DF are highlighted, and finally, future directions of DF research are also briefly outlined.

Risk Assessment of Contaminants in Sewage Sludge Applied on Norwegian Soils

Risk Assessment of Contaminants in Sewage Sludge Applied on Norwegian Soils

Risks for Using FeCl3 Under a Submerged Condition, and Different Water Management to Reduce Uptake of Antimony and Cadmium in a Rice Plant

Soil pollution by multiple metal(loid)s is a common problem, and it is not easy to synchronously reduce their uptake in crops. Compounds containing iron (Fe) are often used to efficiently remediate soil metal(loid) pollution; however, its associated risks did not receive much attention especially under unsuitable soil water conditions. Pot experiments were set up using an antimony (Sb) and cadmium (Cd) co-contaminated soil treated with a continued submergence condition plus 5, 10, or 20 mg kg−1 FeCl3 (Experiment I), or treated with different water management including submergence, intermittent irrigation, and dry farming (Experiment II). Our results showed that the continued submergence resulted in excessive accumulation of arsenic (As) in different tissues of rice plants even if the soil As background concentration is low. High soil moisture content increased the available concentrations of Sb and As, but reduced that of Cd in rhizosphere soils, which was in line with their concentrations in different tissues of rice plants (Experiment II). Under a continued submergence condition, FeCl3 significantly stimulated As concentration in the shoots, roots (excluded Fe20 treatment), and husks, but reduced it in the grains. FeCl3 reduced Sb concentration only in the roots and grains, and reduced Cd concentration only in the husks, suggesting a limited efficiency of FeCl3 to reduce Cd uptake under a submergence condition. In this study, the dynamic changes of As, Sb, and Cd concentrations in soil solution, their available concentrations in rhizosphere soils, their accumulation in root iron/manganese plaques, and the relationships among the above parameters were also discussed. We suggested that if FeCl3 would be used to remediate the contaminated soils by Sb and Cd, dry farming for a short time is needed to avoid As accumulation, and intermittent irrigation is a potential choice to avoid the excessive accumulation of As, Sb, and Cd in the edible parts of rice plants.

Foliar Application of Potassium Mitigates Salinity Stress Conditions in Spinach (Spinacia oleracea L.) through Reducing NaCl Toxicity and Enhancing the Activity of Antioxidant Enzymes

Agronomic biofortification is the purposeful utilization of mineral fertilizers to increase the concentration of desired minerals in edible plant parts for enhancing their dietary intake. It is becoming crucial to enhance the dietary intake of K for addressing hidden hunger and related health issues such as cardiac diseases and hypertension. This study was designed to enhance the potassium concentration in edible parts of spinach through its foliar application under saline environment. The salinity levels of electrical conductivity (EC) = 4, 6, and 8 dS m−1 were applied using sodium chloride (NaCl) along with control. The levels of K for foliar sprays were 5 and 10 mM, along with control. The present experiment was performed under two factorial arrangements in a completely randomized design (CRD). After 60 days of sowing, the crop was harvested. Data regarding growth, ionic, physiological, and biochemical parameters, i.e., shoot dry weight, relative water content, electrolyte leakage, total chlorophyll content, tissue sodium (Na) and K concentration, activities of superoxide dismutase (SOD), and catalase (CAT) were recorded and those were found to be significantly (p ≤ 0.05) affected by foliar application of K on spinach under saline conditions. The highest growth, physiological and biochemical responses of spinach were observed in response to foliar-applied K at 10 mM. It is concluded that agronomic bio-fortification by foliar use of K can be a useful strategy to increase tissue K intakes and minimize Na toxicity in the vegetables studied under saline conditions.

Importance of the Rhizosphere Microbiota in Iron Biofortification of Plants.

Increasing the iron content of plant products and iron assimilability represents a major issue for human nutrition and health. This is also a major challenge because iron is not readily available for plants in most cultivated soils despite its abundance in the Earth’s crust. Iron biofortification is defined as the enhancement of the iron content in edible parts of plants. This biofortification aims to reach the objectives defined by world organizations for human nutrition and health while being environment friendly. A series of options has been proposed to enhance plant iron uptake and fight against hidden hunger, but they all show limitations. The present review addresses the potential of soil microorganisms to promote plant iron nutrition. Increasing knowledge on the plant microbiota and plant-microbe interactions related to the iron dynamics has highlighted a considerable contribution of microorganisms to plant iron uptake and homeostasis. The present overview of the state of the art sheds light on plant iron uptake and homeostasis, and on the contribution of plant-microorganism (plant-microbe and plant-plant-microbe) interactions to plant nutritition. It highlights the effects of microorganisms on the plant iron status and on the co-occurring mechanisms, and shows how this knowledge may be valued through genetic and agronomic approaches. We propose a change of paradigm based on a more holistic approach gathering plant and microbial traits mediating iron uptake. Then, we present the possible applications in plant breeding, based on plant traits mediating plant-microbe interactions involved in plant iron uptake and physiology.

Environmental impact assessment of Egyptian Damietta governorate soils contamination with cadmium

Soil parental materials and anthropogenic activities are the sources of increasing Cd in soils and enrichment in edible parts of plants and creating hazards to animals and human. Thus, it is an important issue to estimate the levels of Cd in soils; straw and grains of rice and wheat plants grown in the soils contaminate with Cd and evaluates human health risk. In surface soil, total Cd (899±497µg kg-1) and Diethylene Triamine Penta Acetate (DTPA) extractable Cd (16.41±13.83µg kg-1) slightly higher by 1.02±0.20 and 1.31±0.45 folds than the subsurface layers, respectively. The DTPA extractable Cd concentration is significantly increased linearly with increasing total soil Cd (r=0.90). Positive significant correlation was found between soils DTPA extractable Cd and soil organic matter (OM) content (r=0.95), while significant negative correlation for both CaCO3 content (r=-0.92) and pH (r=-0.94). In rice Cd concentrations of straw (374±156µg kg-1) and grains (35±16µg kg-1) are significantly correlated with total soil Cd (r=0.89, r=0.86) and DTPA extractable Cd (r=0.84, r=0.74), respectively. Whereas, rice grains Cd is increased with increasing straw Cd (r=0.98). Wheat Cd concentrations of straw (194±71µg kg-1) and grains (18±13µg kg-1) are significantly correlated with total soil Cd (r=0.90, r=0.96) and DTPA extractable Cd (r = 0.91, r=0.95), respectively. Wheat grains Cd is increased with increasing straw Cd (r=0.95). The Cd Transfer factors (TF) as an average is higher in rice grains (0.04±0.014) than wheat grains (0.021±0.016). However, Cd concentrations in the wheat and rice grains are lower than the both EU and WHO/FAO permissible limits (0.24mg kg-1 and 0.4mg kg-1 dry wt., respectively) and so far no potential human health risk is concluded yet.

Three in One: The Potential of Brassica By-Products against Economic Waste, Environmental Hazard, and Metabolic Disruption in Obesity.

A large amount of waste is generated within the different steps of the food supply chain, representing a significant loss of natural resources, plant material, and economic value for producers and consumers. During harvesting and processing, many parts of edible plants are not sold for consumption and end up as massive waste, adding environmental hazards to the list of concerns regarding food wastage. Examples are Brassica oleracea var. Italica (broccoli) by-products, which represent 75% of the plant mass. A growing concern in the Western world is obesity, which results from incorrect lifestyles and comprises an extensive array of co-morbidities. Several studies have linked these co-morbidities to increased oxidative stress; thus, naturally occurring and readily available antioxidant compounds are an attractive way to mitigate metabolic diseases. The idea of by-products selected for their biomedical value is not novel. However, there is innovation underlying the use of Brassica by-products in the context of obesity. For this reason, Brassica by-products are prime candidates to be used in the treatment of obesity due to its bioactive compounds, such as sulforaphane, which possess antioxidant activity. Here, we review the economic and health potential of Brassica bioactive compounds in the context of obesity.

Mitigation effects of selenium on accumulation of cadmium and morpho-physiological properties in rice varieties

Selenium (Se) is a beneficial element, but only when present within its permissible range. Its hyper-accumulation in edible plant parts can cause Se toxicity. This study aimed to develop an agronomic plan for biofortification of rice with Se and reclamation of cadmium (Cd)-contaminated soil, utilizing sodium selenite (Na2SeO3) and cadmium chloride (CdCl2) as soil treatments. Biofortification was performed on two target rice varieties: genotypes 5097A/R2035 and GangYou725, in field trials by applying Cd at a concentration of 0–8 mg kg soil−1 and Se at 0–1 mg kg soil−1. Since these rice varieties have different metabolic specificity, the degree of elemental accumulation, deviations in chlorophyll concentration, activity of photosynthetic apparatus and grain yield were assessed. It was found that application of 1 mg kg−1 Se2O3 decrease Cd content and increased chlorophyll content and photosynthetic activity while grain yield was unaffected by application of the metallic trace-elements. Comparing effects at different stages, we found that the 50% heading stage was most sensitive to metal application. In sum, Se mitigates Cd toxicity, but hyperaccumulation of Se (4 mg kg−1) in polished rice was observed with Cd at 4 and 8 mg kg−1. The elevated level of Cd stress in pot experiments resulted in over-accumulation of Se in the germ and endosperm that poses serious health concerns.

Parameter Values for Estimation of Internal Doses from Ingestion of Radioactive Fallout from Nuclear Detonations.

This paper suggests values or probability distributions for a variety of parameters used in estimating internal doses from radioactive fallout due to ingestion of food. Parameters include those needed to assess the interception and initial retention of radionuclides by vegetation, translocation of deposited radionuclides to edible plant parts, root uptake by plants, transfer of radionuclides from vegetation into milk and meat, transfer of radionuclides into non-agricultural plants and wildlife, and transfer from food and drinking water to mother's milk (human breast milk). The paper includes discussions of the weathering half-life for contamination on plant surfaces, biological half-lives of organisms, food processing (culinary factors), and contamination of drinking water. As appropriate, and as information exists, parameter values or distributions are specific for elements, chemical forms, plant types, or other relevant characteristics. Information has been obtained from the open literature and from publications of the International Atomic Energy Agency. These values and probability distributions are intended to be generic; they should be reviewed for applicability to a given location, time period, or season of the year, as appropriate. In particular, agricultural practices and dietary habits may vary considerably both with geography and over time in a given location.

How Plants Recalibrate Cellular Iron Homeostasis.

Insufficient iron supply poses severe constraints on plants, restricting species with inefficient iron uptake mechanisms from habitats with low iron availability and causing yield losses in agricultural ecosystems. Iron deficiency also poses a severe threat on human health. Anemia resulting from insufficient iron intake is affecting one of four people in the world. It is, therefore, imperative to understand the mechanisms by which plants acquire iron against a huge soil-cell gradient and how iron is distributed within the plant to develop strategies that increase its concentration in edible plant parts. Research into the processes that are employed by plants to adjust cellular iron homeostasis revealed an astonishingly complex puzzle of signaling nodes and circuits, which are intertwined with the perception and communication of other environmental cues such as pathogens, light, nutrient availability and edaphic factors such as pH. In a recent Spotlight issue in this journal, a collection of review articles summarized the state-of-the-art in plant iron research, covering the most active and, debatably, most important topics in this field. Here, we highlight breakthroughs that were reported after the publication date of this review collection, focusing on exciting and potentially influential studies that have changed our understanding of plant iron nutrition.