Cytotoxic and genotoxic effects of metal(oid)s bioactivated in rocket leaves (Eruca vesicaria subsp. sativa Miller)

Rocket (Eruca vesicaria (L.) Cav.) vs. Copper: The Dose Makes the Poison?

The effects of copper addition, from various adsorbents, on the accumulation ability and glucosinolate content of cultivated rocket were studied. Different adsorbents (zeolite NaX, egg shells, substrate, fly ash) were treated with copper(II) solution with an adsorption efficiency of 98.36, 96.67, 51.82 and 39.13%, respectively. The lowest copper content and the highest total glucosinolate content (44.37 μg/g DW and 4269.31 µg/g DW, respectively) were detected in the rocket grown in the substrate with the addition of a substrate spiked with copper(II) ions. Rocket grown in the fly ash-substrate mixture showed an increase in copper content (84.98 μg/g DW) and the lowest total glucosinolate content (2545.71 µg/g DW). On the other hand, when using the egg shells-substrate mixture, the rocket copper content increased (113.34 μg/g DW) along with the total GSLs content (3780.03 µg/g DW), indicating the influence of an adsorbent type in addition to the copper uptake. The highest copper content of 498.56 μg/g DW was detected in the rocket watered with copper(II) solution with a notable decrease in the glucosinolate content, i.e., 2699.29 µg/g DW. According to these results rocket can be considered as a copper accumulator plant.

Health-Promoting Properties of Borage Seed Oil Fractionated by Supercritical Carbon Dioxide Extraction

Borage (Borago officinalis L.) seed oil is an important source of γ–linolenic acid, which is normally used as a treatment against different pathologies. Since the fractionation of this interesting seed oil has many environmental, economic and biological benefits, two borage fractionation techniques after extraction with CO₂ under supercritical conditions have been studied: precipitation in two cyclone separators and countercurrent extraction column. Both techniques have successfully collected free fatty acids in one fraction: (i) two separators set up in series obtained the highest concentration of free fatty acids in separator 2 at 90 bar/40 °C; (ii) when countercurrent extraction column was used, the acidity index of the raffinate stream was independent from the operating conditions (2.6 ± 0.5%). Furthermore, the composition of the fatty acids, as well as their antioxidant and cytotoxic activities, were determined. The profile of the fatty acids obtained by either of these two methods remained unaltered, so that the crude oil exhibited improved antioxidant and cytotoxic properties. All the extracts obtained in the two cyclone separators at the same pressure/temperature conditions displayed high tumouricidal activity against HL 60 promyelocytic leukaemia cells, even if the extracts at 50% concentration from separator 2 presented a lower inhibitory activity (IC₅₀). The extracts from separator 2 at 90 bar/40 °C exhibited the highest anti-proliferative activity at low doses (IC₅₀ of 0.3 μL/mL for the trypan blue exclusion test). To reach the lethal dose—IC₅₀—with the product obtained through countercurrent column fractionation, a concentration of 2 μL/mL of crude borage oil raffinate was required.

Bioaccumulation of selected macro- and microelements and their impact on antioxidant properties and accumulation of glucosinolates and phenolic acids in in vitro cultures of Nasturtium officinale (watercress) microshoots

The study evaluated bioaccumulation capacity of macro- and microelements, their impact on the production of glucosinolates and phenolic acids and antioxidant properties in a microshoot culture model of Nasturtium officinale. Elements: calcium, chromium, copper, iron, lithium, magnesium, selenium and zinc were supplemented in different salt concentrations to culture media. Bioaccumulation of elements [mg/100 gDW] varied from 1.24 (Li,1 mg/l) to 498.62 (Cr,50 mg/l) and was dependent on the type of element and its concentration. The bioconcentration factor (BCF) ranged from 11.37 (Li,25 mg/l) to 4467.00 (Ca,1 mg/l). The total glucosinolate contents [mg/100gDW] varied from 108.11 (Cr,1 mg/l) to 172.90 (Ca,1 mg/l). The presence of four phenolic acids was confirmed in the microshoots. Their total contents [mg/100gDW] ranged from 19.35 (Mg,10 mg/l) to 139.21 (Fe,50 mg/l). The highest antioxidant activity [nM trolox/mgDW], as evaluated by CUPRAC and QUENCHER-CUPRAC methods, was equal to 55.50 (Cu,1 mg/l) and 161.10 (Li,5 mg/l), respectively. The results proved good correlations between all studied parameters.

The role of epicuticular waxes on foliar metal transfer and phytotoxicity in edible vegetables: case of Brassica oleracea species exposed to manufactured particles

The rapid industrialization and urbanization of intra- and peri-urban areas at the world scale are responsible for the degradation of the quality of edible crops, because of their contamination with airborne pollutants. Their consumption could lead to serious health risks. In this work, we aim to investigate the phytotoxicity induced by foliar transfer of atmospheric particles of industrial/urban origin. Leaves of cabbage plants (Brassica oleracea var. Prover) were contaminated with metal-rich particles (PbSO₄ CuO and CdO) of micrometer size. A trichloroacetic acid (TCA) treatment was used to inhibit the synthesis of the epicuticular waxes in order to investigate their protective role against metallic particles toxicity. Besides the location of the particles on/in the leaves by microscopic techniques, photosynthetic activity measurements, genotoxicity assessment, and quantification of the gene expression have been studied for several durations of exposure (5, 10, and 15 days). The results show that the depletion of epicuticular waxes has a limited effect on the particle penetration in the leaf tissues. The stomatal openings appear to be the main pathway of particles entry inside the leaf tissues, as demonstrated by the overexpression of the BolC.CHLI1 gene. The effects of particles on the photosynthetic activity are limited, considering only the photosynthetic F_v/F_m parameter. The genotoxic effects were significant for the contaminated TCA-treated plants, especially after 10 days of exposure. Still, the cabbage plants are able to implement repair mechanisms quickly, and to thwart the physiological effects induced by the particles. Finally, the foliar contamination by metallic particles induces no serious damage to DNA, as observed by monitoring the BolC.OGG1 gene.

Arsenic uptake by arugula (Eruca vesicaria, L.) cultivars as affected by phosphate availability

To assess the importance of variation among arugula (Eruca vesicaria subsp. sativa) cultivars in the ability to accumulate arsenic (As) in above-ground tissues, uptake of As by 16 cultivars was measured in the field and in hydroponic culture. In the field trial on soil contaminated by past pesticide use, As soil-plant uptake coefficients varied by a factor of 2.7 among different cultivars, approaching a value of one for the strongest accumulators. Compared to the field assay, hydroponically grown arugula accumulated much lower concentrations of As when nutrient solutions contained standard (high) concentrations of phosphate along with 1.0 mg L^-1 As in the form of soluble arsenate. However, As accumulation was much greater in hydroponic culture using low-P nutrient solutions, an indication that phosphate strongly competed with arsenate for root uptake. Analysis of arugula roots after exposure to arsenate at 1.0 mg As L^-1 and low phosphate revealed from 24 to 400 times greater As concentration in roots than tops, with S concentrations significantly greater in As-exposed than control roots. This indicated greater sulfate uptake by roots exposed to arsenate, and suggested that thiol-mediated As immobilization occurred in the roots which strongly restricted translocation to the tops.

Identification of a Quality Marker (Q-Marker) of Danhong Injection by the Zebrafish Thrombosis Model

Quality-marker (Q-marker) is an emerging concept to ensure the quality and batch-to-batch consistency of Chinese medicine (CM). However, significant difficulties remain in the identification of Q-markers due to the unclear relationship between complex chemical compositions and the pharmacological efficacy of CM. In the present study, we proposed a novel strategy to identify the potential Q-marker of danhong injection (DHI) by an in vivo zebrafish thrombosis model. The anti-thrombotic effects of DHI and its major constituents were evaluated by the zebrafish model of arachidonic acid (AA)-induced thrombosis. The results indicated that DHI can attenuate tail venous thrombus and recover the decrease of heart red blood cell (RBC) intensity in a dose-dependent manner. The result that DHI prevented the formulation of thrombosis in zebrafish was also validated in the zebrafish thrombosis model with green fluorescence protein (GFP)-labeled hemoglobin. The major components of DHI, namely danshen (DS) and honghua (HH), as well as the major chemical constituents of DHI, also exerted anti-thrombotic effects, among which rosmarinic acid (RA) and p-coumaric acid (pCA) showed moderate anti-thrombotic effects. This is the first time that pCA from HH has been found as an active compound exerting an anti-thrombotic effect in a dose-dependent manner, whose IC₅₀ value is approximately 147 μg/mL. By analyzing 10 batches of normal DHI samples and five abnormal samples by high-performance liquid chromatography (HPLC), we found the contents of pCA and RA can be positively correlated to the anti-thrombotic effect of DHI, suggesting that pCA and RA could be potential Q-markers of DHI to ensure batch-to-batch consistency. Our findings illustrated that discovering major active compounds from CM by in vivo pharmacological models can be a useful approach to identifying Q-markers of CM, and in vivo pharmacological models can be a potential tool to evaluate batch-to-batch consistency of CMs.

Evaluation of genotoxic variations in plant model systems in a case of metal stressors

This study was designed to assess the effects of long term, high metal exposition (cadmium, lead, copper, nickel and zinc) on DNA damage in four plant model systems [Taraxacum officinale (Asteraceae), Matricaria recutita L. (Asteraceae), Robinia pseudoacacia L. (Fabaceae), and Urtica dioica (Urticaceae)]. DNA stability was investigated by a Random Amplified Polymorphic DNA (RAPD) technique. Agarose-gel electrophoresis revealed total of 37 bands with different molecular weights ranging from 1250 to 5000 bp. It generated distinctive polymorphism value of 72.97% (27 bands) total in four plant species investigated. The dendrogram constructed using NTSYSpc programme showed that there is grouping in separate clusters of the same plant model collected from two different areas (metal-exposed and control samples). The study concluded that the long term metal-exposing periods had genotoxic stress on macromolecules of plant model systems investigated and biomarkers used should be augmented for reliable estimates of genotoxicity after exposure of plants to metal stressors.

Effects of long-term irrigation with untreated municipal wastewater on soil properties and crop quality

Irrigating crops with untreated wastewater leads to elevated concentrations of heavy metals both in soil and cultivated crops. The current study was designed to determine heavy metal (i.e., Pb, Cd, Cr, Cu, Ni, Zn, Hg) accumulation in Konya soils in selected nine sites irrigated with wastewater for over 40 years. Non-irrigated soil samples and soil samples irrigated with well water were taken as control samples. Transport of these pollutants to the wheat samples cultivated in the investigated site was also examined. The obtained results reveal that high alkaline properties and clay structure of Konya soil reduce the mobility of contaminants and cause accumulation in the top layer of soil. Intense effect of wastewater irrigation on soil EC was determined. The highest concentrations of Pb, Cr, Cu, Cd, Zn, Ni, and Hg in wastewater irrigated soil were 5.32, 37.1, 31.5, 11.4, 91.5, 134, and 0.34 mg kg(-1), respectively. Wastewater irrigated soils were strongly polluted by means of Cd (8.23-11.6 mg kg(-1)) and moderately to strongly polluted by means of Ni (47.7-134 mg kg(-1)), exceeding Maximum Admissible Concentrations for Trace Elements in Agricultural Soils and Sewage Sludge Regulation limit values of Turkey. Maximum concentrations found for Pb, Cr, Cu, Cd, Zn, and Ni in wastewater irrigated wheat grain were 8.44, 1.30, 9.10, n.d, 29.31, and 0.94 mg kg(-1), respectively. Besides, Hg was not detected in any samples of wheat grain. Based on the regulation of Turkish Food Codex, Pb contamination in wheat samples grown in the sampling site was evidenced.

In vivo genotoxicity and cytotoxicity assessment of cadmium chloride in peripheral erythrocytes of Labeo rohita (Hamilton)

Cadmium chloride (CdCl2) induced genotoxicity and cytotoxicity has been assessed in the peripheral blood erythrocytes of freshwater fish Labeo rohita exposed to 0.37 and 0.62mg/L of CdCl2 in water for 100 days. The blood samples of the fish were collected at different intervals (days 1, 3, 5, 10, 15, 30, 60 and 100) of exposure period to analyze DNA damage using comet assay and the occurrence of micronuclei and other cellular anomalies. The results of comet assay showed a significant increase in the mean percentage of tail DNA at both the concentrations. Exposure to CdCl2 also induced micronuclei in addition to many nuclear abnormalities such as nuclear bud, binucleates, lobed, notched and vacuolated nuclei. Cytoplasmic abnormalities like echinocytes, acanthocytes, notched, microcytes and cells with vacuolated cytoplasm were also observed. The metal exposed groups showed significant variation in the frequency of cellular abnormalities as well as the extent of DNA damage in comparison to controls. These frequencies increased significantly (p<0.05) in concentration dependent manner, peaking on 10th day while a decreasing trend was observed after 15 days of the exposure period.