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Identification and Characterization of Phenolic and Flavonoids Compounds Extracted from Tunisian Pomegranate Fruit Peel Exposed to Air Pollution: Gabes City, Tunisia
2021
Ben Amor, Afef | Ben Atia Zrouga, Khaoula | Chaira, Nizar | Ben Yahia, Leila | Nagaz, Kamel
The pomegranate (Punica granatum) fruit peel exposed to mixture air pollutants were collected from two sites with different air quality around the industrial area of Gabes city, Tunisia. The first site presented the ‘Polluted site’, which is situated in the oasis close to the industrial area. While, the second site referred to the ‘Control site’ located at 37 km from the industrial area. Using HPLC ES-MS, 21 phenols were identified and quantified in methanol extract from pomegranate fruit peel. The results showed that various phytochemical substances, including phenols acids and flavonoids, were identified and quantified in the peel extract. The polyphenols content and the flavonoids contents in peel obtained from polluted site were higher than that collected from the control site. The concentrations of the identified polyphenols were ranged between 0.39 and 7803.68 mg/ kg DW. The stimulation of some free phenolic compounds such syringic acid, transfrulic acid, epicatechin, rutin and quercetin was enregistred only in peel collected from contaminated environment. The quali-qualitative changes between sites are probably related to the difference in the air quality. The increase of polyphenols could be implicated during adaptive mechanisms under air pollution. Phenolic composition changes in Punica granatum peel could be also suggested as useful approach air pollution monitoring.
Show more [+] Less [-]Inflammatory and oxidative stress responses of healthy adults to changes in personal air pollutant exposure
2020
Hu, Xinyan | He, Linchen | Zhang, Junfeng | Qiu, Xinghua | Zhang, Yinping | Mo, Jinhan | Day, Drew B. | Xiang, Jianbang | Gong, Jicheng
Exposure to air pollutants has been associated with respiratory and cardiovascular mortality, but the underlying molecular mechanisms remain inadequately understood. We aimed to examine molecular-level inflammatory and oxidative stress responses to personal air pollutant exposure. Fifty-three healthy adults aged 22–52 were measured three times for their blood inflammatory cytokines and urinary malondialdehyde (MDA, an oxidative stress biomarker) within 2 consecutive months. Pollutant concentrations monitored indoors and outdoors were combined with the time-activity data to calculate personal O₃, PM₂.₅, NO₂, and SO₂ exposures averaged over 12 h, 24 h, 1 week, and 2 weeks, respectively, prior to biospecimen collection. Inflammatory cytokines and MDA were associated with pollutant exposures using linear mixed-effects models controlling for various covariates. After adjusting for a co-pollutant, we found that concentrations of proinflammatory cytokines were significantly and negatively associated with 12-h O₃ exposures and significantly but positively associated with 2-week O₃ exposures. We also found significant and positive associations of proinflammatory cytokines with 12-h and 24-h NO₂ exposures, respectively. However, we did not find clear associations of PM₂.₅ and SO₂ exposure with proinflammatory cytokines and with MDA. The removal of an O₃-generating electrostatic precipitator in the mechanical ventilation systems of the offices and residences of the subjects was associated with significant decreases in IL-1β, IL-2, IL-6, IL-8, IL-17A, and TNF-α. These findings suggest that exposure to O₃ for different time durations may affect systemic inflammatory responses in different ways.
Show more [+] Less [-]Determination of six groups of mycotoxins in Chinese dark tea and the associated risk assessment
2020
Chinese dark tea is widely enjoyed for its multiple health-promoting effects and pleasant taste. However, its production involves fermentation by microbiota in raw tea, some of which are filamentous fungi and thus potential mycotoxin producers. Accordingly, whether mycotoxins pose health risk on dark tea consumption has become a public concern. In this study, a cleaning method of multi-functional column (MFC) and immunoaffinity column (IAC) in tandem combined to HPLC detection was developed and validated for determining ten mycotoxins of six groups (i.e., aflatoxins of B₁, B₂, G₁ and G₂, ochratoxin A, zearalenone, deoxynivalenol, fumonisins of B₁, B₂, and T-2) in dark teas. The interferences from secondary metabolites were effectively reduced, and the sensitivities and recoveries of the method were qualified for tea matrices. Six groups mycotoxins were determined in 108 samples representing the major Chinese dark teas by using the new method. Subsequently, the dietary exposure and health risks were evaluated for different age and gender groups in Kunming and Pu’er in China and Ulan Bator in Mongolia. The occurrence of zearalenone was 4.63% and that of ochratoxin A was 1.85%, with the other four groups mycotoxins were below the limits of quantification. The hazard index values for the five groups’ non-carcinogenic mycotoxins were far below 1.0. The deterministic risk assessment indicated no non-carcinogenic risks for dark tea consumption in the three areas. Probabilistic estimation showed that the maximum value of 95th percentile carcinogenic risk value for the aflatoxins was 2.12 × 10⁻⁸, which is far below the acceptable carcinogenic risk level (10⁻⁶). Hereby, six groups mycotoxins in Chinese dark tea showed no observed risk concern to consumers.
Show more [+] Less [-]The lipid metabolism alteration of three spirocyclic tetramic acids on zebrafish (Danio rerio) embryos
2019
Zhang, Jie | Qian, Le | Teng, Miaomiao | Mu, Xiyan | Qi, Suzhen | Chen, Xiangguang | Zhou, Yimeng | Cheng, Yi | Pang, Sen | Li, Xuefeng | Wang, Chengju
Spirocyclic tetramic acids are widely used in controlling phytophagous mite species throughout the world. the data set is incomplete and provides insufficient evidence for drawing the same conclusion for fish. To fill the gap whether these acaricides alter lipid metabolism on vertebrates, zebrafish embryos exposed to a series concentration of pesticides, the developmental effects, enzyme activities and levels of gene expression were assessed, battery of biomarker utilized by the integrated biomarker response (IBRv2) model. The 96 h-LC₅₀ of spirodiclofen, spiromesifen and spirotetramat were 0.14, 0.12 and 5.94 mg/L, respectively. Yolk sac deformity, pericardial edema, spinal curvature and tail malformation were observed. Three spirocyclic acids were unfavouring the lipid accumulation of by inhibited the acetyl-CoA carboxylase (ACC), fatty acid synthesis (FAS), fatty acid binding proteins (FABP2) and lipoprotein lipase (LPL) activity. The total cholesterol (TCHO) level significantly decreased in the 0.072 mg/L spirodiclofen group and 0.015 and 0.030 mg/L in the spiromesifen groups. No expected change in spirotetramat group on the TCHO and triglycerides (TGs) levels for any of the treatments. The mRNA levels of the genes related to lipid metabolism also significantly altered. In both spirodiclofen and spiromesifen, ACC achieved the highest scores among a battery of biomarkers using integrated biomarker response (IBRv2). The results suggest that spiromesifen was the most toxic for embryos development and spirodiclofen was the most toxic for lipid metabolism in embryos. The 0.07 mg/L of spirodiclofen, 0.05 mg/L of spiromesifen and 2.00 mg/L would cause malformation on zebrafish embryos. This study will provide new insight that fatty acid metabolism may be a suitable biomarker for the spirocyclic tetramic acids in fish species.
Show more [+] Less [-]Occurrence of neonicotinoids and fipronil in estuaries and their potential risks to aquatic invertebrates
2019
Hano, Takeshi | Ito, Katsutoshi | Ohkubo, Nobuyuki | Sakaji, Hideo | Watanabe, Akio | Takashima, Kei | Satō, Taku | Sugaya, Takuma | Matsuki, Kosuke | Onduka, Toshimitsu | Ito, Mana | Somiya, Rei | Mochida, Kazuhiko
This study aimed to evaluate and qualify field-based potential risks of seven neonicotinoid and phenylpyrazole (fipronil) insecticides on aquatic invertebrates, including estuary-resident marine crustaceans. One hundred and ninety-three estuarine water samples, with salinity ranging from 0.5 to 32.7, were collected from four estuarine sites in the Seto Inland Sea of Japan, in 2015–2018 and the insecticide levels were measured. Five neonicotinoid and fipronil insecticides were successfully identified, and their occurrence varied temporally. Marine crustaceans were simultaneously harvested every month from one of the estuarine water sampling sites in 2015–2017. Three predominant crustacean species, kuruma prawn (Penaeus japonicus), sand shrimp (Crangon uritai), and mysid (Neomysis awatschensis), were captured and their seasonal presence was species independent. A 96-h laboratory toxicity study with the insecticides using kuruma prawn, sand shrimp, and a surrogate mysid species (Americamysis bahia) indicated that fipronil exerted the highest toxicity to the three crustaceans. Using both toxicity data and insecticide occurrence in estuarine water (salinity ≥10, n = 169), the potential risks on the three marine crustaceans were quantified by calculating the proportion of mixture toxicity effects (Pₘᵢₓ). The Pₘᵢₓ of seven neonicotinoids on the crustaceans was less than 0.8%, which is likely to be too low to indicate adverse effects caused by the insecticides. However, short temporal detection of fipronil (exclusively in June and July) significantly affected the Pₘᵢₓ, which presented the maximal Pₘᵢₓ values of 21%, 3.4%, and 72% for kuruma prawn, sand shrimp, and mysid, respectively, indicating a significant effect on the organisms. As for estuarine water (salinity <10), some water samples contained imidacloprid and fipronil exceeding the freshwater benchmarks for aquatic invertebrates. The present study provides novel insights into the seasonally varying risks of insecticides to estuarine crustaceans and highlights the importance of considering whether ecological risk periods coincide with crustacean presence.
Show more [+] Less [-]Environmental six-ring polycyclic aromatic hydrocarbons are potent inducers of the AhR-dependent signaling in human cells
2020
Vondráček, Jan | Pěnčíková, Kateřina | Ciganek, Miroslav | Pivnička, Jakub | Karasová, Martina | Hýžďalová, Martina | Strapáčová, Simona | Pálková, Lenka | Neča, Jiří | Matthews, Jason | Lom, Michal Vojtíšek | Topinka, Jan | Milcová, Alena | Machala, Miroslav
The toxicities of many environmental polycyclic aromatic hydrocarbons (PAHs), in particular those of high-molecular-weight PAHs (with MW higher than 300), remain poorly characterized. The objective of this study was to evaluate the ability of selected environmentally relevant PAHs with MW 302 (MW302 PAHs) to activate the aryl hydrocarbon receptor (AhR), since this represents a major toxic mode of action of PAHs. A large number of the evaluated compounds exhibited strong AhR-mediated activities, in particular in human models. The studied MW302 PAHs also significantly contributed to the overall calculated AhR activities of complex environmental mixtures, including both defined standard reference materials and collected diesel exhaust particles. The high AhR-mediated activities of representative MW302 PAHs, e.g. naphtho[1,2-k]fluoranthene, corresponded with the modulation of expression of relevant AhR target genes in a human lung cell model, or with the AhR-dependent suppression of cell cycle progression/proliferation in estrogen-sensitive cells. This was in a marked contrast with the limited genotoxicity of the same compound(s). Given the substantial levels of the AhR-activating MW302 PAHs in combustion particles, it seems important to continue to investigate the toxic modes of action of this large group of PAHs associated with airborne particulate matter.
Show more [+] Less [-]Metabolic responses and their correlations with phytochelatins in Amaranthus hypochondriacus under cadmium stress
2019
Xie, Mengdi | Chen, Wenqing | Lai, Xicong | Dai, Haibo | Sun, Hui | Zhou, Xiaoyong | Chen, Tongbin
Phytochelatins (PCs) play a vital role in the tolerance and enrichment of cadmium (Cd) in higher plants by chelating with Cd2+. The aim of this study was to perform a full-scale metabolomics analysis of metabolic responses highly correlated with PCs generation. These metabolites and metabolic pathways were expected to promote PCs generation and further optimize Cd absorption in plants. In the current study, Amaranthus hypochondriacus, a potential species for phytoremediation, was first adopted to investigate physiological responses to Cd stress via LCMS/MS-based metabolomics and the HPLC based determination of thiol compounds. The results showed that the leaves of A. hypochondriacus under high Cd stress accumulated 40 times the amount of Cd compared to the leaves of the plants not under Cd stress and had an increased content of three types of PCs. Metabolomics qualitatively identified 12084 substances in total, among which 41 were significantly different metabolites (SDMs) between the two groups and involved in 7 metabolic pathways. Among the SDMs, 12 metabolites were highly linearly correlated with PCs involved in three pathways (Val, Leu and Ile biosynthesis; Ala, Asp and Glu metabolism; and Arg and Pro metabolism). These results provide an innovative method to promote PCs synthesis for the restoration of Cd-contaminated-soil.
Show more [+] Less [-]Removal of seven endocrine disrupting chemicals (EDCs) from municipal wastewater effluents by a freshwater green alga
2019
Bai, Xuelian | Acharya, Kumud
The present endocrine disrupting chemicals (EDCs) in wastewater effluents due to incomplete removal during the treatment processes may cause potential ecological and human health risks. This study evaluated the removal and uptake of seven EDCs spiked in two types of wastewater effluent (i.e., ultrafiltration and ozonation) and effluent cultivated with the freshwater green alga Nannochloris sp. In ultrafiltration effluent cultivated with Nannochloris sp. for 7 days, the removal rate of 17β-estradiol (E2), 17α-ethinylestradiol (EE2), and salicylic acid (SAL) was 60%; but Nannochloris sp. did not promote the removal of other EDCs studied. The algal-mediated removal of E2, EE2, and SAL was attributed to photodegradation and biodegradation. Triclosan (TCS) underwent rapid photodegradation regardless of adding algae in the effluent with 63%–100% removal within 7 days. Triclosan was also found associated with algal cells immediately after adding algae, and thus the primary mechanisms involved were photodegradation and bioremoval (i.e., bioadsorption and bioaccumulation). After algal cultivation, TCS still has a bioaccumulation potential to pose high risks within the food web and the endocrine disrupting properties of the residual estrogens in the effluent are not eliminated. Algal cultivation can be exploited to treat wastewater effluents but the removal efficiencies of EDCs highly depend on chemical types.
Show more [+] Less [-]Degradation of cyclophosphamide and 5-fluorouracil by UV and simulated sunlight treatments: Assessment of the enhancement of the biodegradability and toxicity
2016
Lutterbeck, Carlos Alexandre | Wilde, Marcelo Luís | Baginska, Ewelina | Leder, Christoph | Machado, Ênio Leandro | Kümmerer, Klaus
The presence of pharmaceuticals in the environment has triggered concern among the general population and received considerable attention from the scientific community in recent years. However, only a few publications have focused on anticancer drugs, a class of pharmaceuticals that can exhibit cytotoxic, genotoxic, mutagenic, carcinogenic and teratogenic effects. The present study investigated the photodegradation, biodegradation, bacterial toxicity, mutagenicity and genotoxicity of cyclophosphamide (CP) and 5-fluorouracil (5-FU). The photodegradation experiments were performed at a neutral to slight pH range (7–7.8) using two different lamps (medium-pressure mercury lamp and a xenon lamp). The primary elimination of the parent compounds was monitored by means of liquid chromatography tandem mass spectrometry (LC-IT-MS/MS). NPOC (non-purgeable organic carbon) analyses were carried out in order to assess mineralization rates. The Closed Bottle Test (CBT) was used to assess ready biodegradability. A new method using Vibrio fischeri was adopted to evaluate toxicity. CP was not degraded by any lamp, whereas 5-FU was completely eliminated by irradiation with the mercury lamp but only partially by the Xe lamp. No mineralization was observed for the experiments performed with the Xe lamp, and a NPOC removal of only 18% was registered for 5-FU after 256 min using the UV lamp. Not one of the parent compounds was readily biodegradable in the CBT. Photo transformation products (PTPs) resulting from photolysis were neither better biodegradable nor less toxic than the parent compound 5-FU. In contrast, the results of the tests carried out with the UV lamp indicated that more biodegradable and non-toxic PTPs of 5-FU were generated. Three PTPs were formed during the photodegradation experiments and were identified. The results of the in silico QSAR predictions showed positive mutagenic and genotoxic alerts for 5-FU, whereas only one of the formed PTPs presented positive alerts for the genotoxicity endpoint.
Show more [+] Less [-]Day-to-day variability of toxic events induced by organic compounds bound to size segregated atmospheric aerosol
2015
Topinka, Jan | Rossner, Pavel | Milcová, Alena | Schmuczerová, Jana | Pěnčíková, Kateřina | Rossnerová, Andrea | Ambrož, Antonín | Štolcpartová, Jitka | Bendl, Jan | Hovorka, Jan | Machala, Miroslav
This study quantified the temporal variability of concentration of carcinogenic polycyclic aromatic hydrocarbons (c-PAHs), genotoxicity, oxidative DNA damage and dioxin-like activity of the extractable organic matter (EOM) of atmospheric aerosol particles of aerodynamic diameter (dae, μm) coarse (1 < dae < 10), upper- (0.5 < dae < 1) and lower-accumulation (0.17 < dae < 0.5) and ultrafine (<0.17) fractions. The upper accumulation fraction formed most of the aerosol mass for 22 of the 26 study days and contained ∼44% of total c-PAHs, while the ultrafine fraction contained only ∼11%. DNA adduct levels suggested a crucial contribution of c-PAHs bound to the upper accumulation fraction. The dioxin-like activity was also driven primarily by c-PAH concentrations. In contrast, oxidative DNA damage was not related to c-PAHs, as a negative correlation with c-PAHs was observed. These results suggest that genotoxicity and dioxin-like activity are the major toxic effects of organic compounds bound to size segregated aerosol, while oxidative DNA damage is not induced by EOM.
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