The present study synthesizes Zn-TiO2 photocatalyst via a simple and economic green rout, in which Green Tea is applied as a green reducing agent due to the presence of polyphenols Molecules. Polyphenol molecules in green tea act as a reductant, thus changing Zn2+ to metallic Zn. The by-produced nanocmposites are characterized by using XRD, FESEM, EDS, and DRS. Zn-TiO2 photocatalyst possesses great efficient charge separation properties. In order to investigate the presence of Zn, different weight ratio of Zn to TiO2 (viz. 5 wt%, 10 wt%, 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt%, 45 wt%, and 50 wt%) have been synthesized and their performance in Acid Orange 7 (AO7) photodegradation, compared with pure TiO2. According to the results, the compound with 25 wt% Zn shows 97% degradation of AO7 as a model pollutant. Also, it has been shown that after three tests with EDTA, benzoic acid, and under Ar gas, photodegradation of AO7 with Zn-TiO2 photocatalyst mainly depends on photogenerated holes.

Pieces of glass as solid wastes were recycled in the synthesis of highly order MCM-41 that decorated by green fabricated Co₃O₄ nanoparticles using the green extract of green tea leaves forming novel green nano-composite. The synthetic Co₃O₄/MCM-41 exhibit high surface area, low bandgap energy (1.63 eV), and typical spherical morphology decorated by Co₃O₄ nanoparticles. The composite was evaluated as green photocatalyst in effective oxidation of methyl parathion pesticide in the presence of a visible light source. The degradation results revealed complete removal of 50 mg/L and 100 mg/L after 60 min and 90 min, respectively using 0.25 of the catalyst at pH 8. The detection of the TOC in the treated methyl parathion solution gives strong indications about the formation of organic intermediate compounds during the oxidation steps. The main detected intermediate compound are C₆H₅OH(NO₂), C₆H₅OH, (CH₃O)₃P(S), C₆H₄(OH)₂, C₆H₃(OH)₃, C₆H₄(NH₂)OP(O)(OCH₃)₂, (CH₃O)₂P(O)OH, (CH₂)₂C(OH)OH(CHO)OC(O), and HO₂C(CH₂)₂C(O)CHO. The detected intermediate compounds converted into SO₄²⁻, PO₄³⁻, NO₃⁻, and CO₂ under the extensive photocatalytic of them over Co₃O₄/MCM-41. The oxidizing species trapping test verified the controlling of the methyl parathion degradation pathway by the hydroxyl radicals. Finally, the composite showed significant reusability properties and applied five times in the oxidation of methyl parathion with considerable degradation percentages.

The increase in ambient fine dust particles (FDP) due to urbanization and industrialization has been identified as a major contributor to air pollution. It has become a serious issue that threatens human health because it causes respiratory diseases and skin aging. In the present study, the protective effect of the green tea catechin, (−)-epigallocatechin gallate (EGCG), against FDP (ERM-CZ100)-stimulated skin aging in human dermal fibroblasts (HDFs) was investigated. The results demonstrate that EGCG significantly and dose-dependently scavenged intracellular reactive oxygen species (ROS) in and increased the viability of FDP-stimulated HDFs. In addition, EGCG dose-dependently recovered collagen synthesis and inhibited intracellular elastase and collagenase activities. Moreover, EGCG decreased the expression of human matrix metalloproteinases (MMPs) via regulation of nuclear factor kappa B (NF-κB), activator protein 1 (AP-1), and mitogen-activated protein kinases (MAPKs) signaling pathways in FDP-stimulated HDFs. This study suggests that EGCG is a potential anti-aging candidate that can be used for FDP-induced skin aging as a therapeutic agent itself or as an ingredient in pharmaceutical and cosmeceutical products.

Organic-matter decomposition has long been proposed as a tool to assess stream functional integrity, but this indicator largely depends on organic-matter selection. We assessed eight decomposition-based indicators along two well-known environmental gradients, a nutrient-enrichment gradient (0.2–1.4 mg DIN/L) in central Portugal and an acidification gradient (pH: 4.69–7.33) in north-eastern France to identify the most effective organic-matter indicator for assessing stream functional integrity. Functional indicators included natural leaf litter (alder and oak) in 10-mm and 0.5-mm mesh bags, commercial tea (Lipton green and rooibos teas in 0.25-mm mesh bags), wood sticks (wood tongue depressors) and cotton strips. Biotic indices based on benthic macroinvertebrates (IPtIN for Portugal and IBGN for France) were calculated to compare the effectiveness of structural and functional indicators in detecting stream impairment and to assess the relationship between both types of indicators. The effectiveness of organic-matter decomposition rates as a functional indicator depended on the stressor considered and the substrate used. Decomposition rates generally identified nutrient enrichment and acidification in the most acidic streams. Decomposition rates of alder and oak leaves in coarse-mesh bags, green and rooibos teas and wood sticks were positively related with pH. Only decomposition rates of rooibos tea and wood sticks were related with DIN concentration; decomposition rates along the nutrient-enrichment gradient were confounded by differences in shredder abundance and temperature among streams. Stream structural integrity was good to excellent across streams; the IPtIN index was unrelated to DIN concentration, while the IBGN index was positively related with pH. The relationships between decomposition rates and biotic indices were loose in most cases, and only decomposition rates of alder leaves in coarse-mesh bags and green tea were positively related with the IBGN. Commercial substrates may be a good alternative to leaf litter to assess stream functional integrity, especially in the case of nutrient enrichment.

Exposure to the emerging contaminant bisphenol A (BPA) is ubiquitous and associated with cardiovascular disorders. BPA effect as endocrine disruptor is widely known but other mechanisms underlying heart disease, such as epigenetic modifications, remain still unclear. A compound of green tea, epigallocatechin gallate (EGCG), may act both as anti-estrogen and as inhibitor of some epigenetic enzymes. The aims of this study were to analyze the molecular processes related to BPA impairment of heart development and to prove the potential ability of EGCG to neutralize the toxic effects caused by BPA on cardiac health. Zebrafish embryos were exposed to 2000 and 4000 μg/L BPA and treated with 50 and 100 μM EGCG. Heart malformations were assessed at histological level and by confocal imaging. Expression of genes involved in cardiac development, estrogen receptors and epigenetic enzymes was analyzed by qPCR whereas epigenetic modifications were evaluated by whole mount immunostaining. BPA embryonic exposure led to changes in cardiac phenotype, induced an overexpression of hand2, a crucial factor for cardiomyocyte differentiation, increased the expression of estrogen receptor (esr2b), promoted an overexpression of a histone acetyltransferase (kat6a) and also caused an increase in histone acetylation, both mechanisms being able to act in sinergy. EGCG treatment neutralized all the molecular alterations caused by BPA, allowing the embryos to go on with a proper heart development. Both molecular mechanisms of BPA action (estrogenic and epigenetic) likely lying behind cardiogenesis impairment were successfully counteracted by EGCG treatment.

Polycyclic aromatic hydrocarbons (PAHs) have been detected in some commercial teas around the world and pose a threat to tea consumers. However, green tea polyphenols (GTP) possess remarkable antioxidant and anticancer effects. In this study, the potential of GTP to block the toxicity of the model PAH phenanthrene was examined in human embryo lung fibroblast cell line HFL-I. Both GTP and phenanthrene treatment individually caused dose-dependent inhibition of cell growth. A full factorial design experiment demonstrated that the interaction of phenanthrene and GTP significantly reduced growth inhibition. Using the median effect method showed that phenanthrene and GTP were antagonistic when the inhibitory levels were less than about 50%. Apoptosis and cell cycle detection suggested that only phenanthrene affected cell cycle significantly and caused cell death; GTP lowered the mortality of HFL-I cells exposed to phenanthrene; However, GTP did not affect modulation of the cell cycle by phenanthrene.

Traditional tea (Camellia sinensis) and herbal tea are being consumed across the world. However, long term consumption of tea can increase the chances of fluorosis owing to the presence of fluoride (F) in teas. Therefore, it is imperative to assess the health risk associated with tea consumption. The main objectives of this study were to: 1) estimate total F in 47 popular teas, including traditional and herbal teas and F concentrations in 1% (w/v) infusion of 5 min, and 2) assess the exposure risks of F from tea consumption in children and adults. The data showed that total F was the least in herbal teas (33–102 mg/kg) and their infusions (0.06–0.69 mg/L) compared to traditional teas (296–1112 mg/kg) and their infusions (1.47–6.9 mg/L). During tea infusion, 6–96% and 18–99% of the F was released into the water from herbal and traditional teas, respectively. Ten samples of traditional teas, including five green teas had chronic daily intake (CDI) values of F > 0.05 mg/d/kg bw, the stipulated permissible limits of F intake from all sources. Although the F from teas posed no immediate health hazards with hazard quotient <1, some tea samples could potentially contribute >4 mg F/d, thereby adding to the overall F burden. Therefore, together with F from food and water sources, daily F consumptions from teas might increase its health risks to humans. So, caution should be excised when drinking teas containing high F.

The objective of present study was to obtain the fixation of nano zero valent iron (nZVI) particles on a permeable matrix and evaluate the performance of this composite material for the removal of Cr(VI) from contaminated waters. The experiments were carried out using the cationic resin Dowex 50WX2 as porous support of the iron nanoparticles. The work was carried out in two phases. The first phase involved the fixation of nZVI on the resin matrix. The resin granules were initially mixed with a FeCl3 solution to obtain the adsorption of Fe(III). Then the Fe(III) loaded resin (RFe) was treated with polyphenol solutions to obtain the reduction of Fe(III) to the elemental state. Two polyphenol solutions were tested as reductants, i.e. green tea extract and gallic acid. Green tea was found to be inefficient, probably due to the relatively big size of the contained polyphenol molecules, but gallic acid molecules were able to reach adsorbed Fe(III) and reduce the cations to the elemental state. The second phase was focused on the investigation of Cr(VI) reduction kinetics using the nanoiron loaded resins (R-nFe). It was found that the reduction follows a kinetic law of first order with respect to Cr(VI) and to the embedded nanoiron. Compared to other similar products, this composite material was found to have comparable performance regarding reaction rates and higher degree of iron utilization. Namely the rate constant for the reduction of Cr(VI), in the presence of 1 mM nZVI, was equivalent to 1.4 h of half-life time at pH 3.2 and increased to 24 h at pH 8.5. The degree of iron utilization was as high as 0.8 mol of reduced Cr(VI) per mole of iron. It was also found that this composite material can be easily regenerated and reused for Cr(VI) reduction without significant loss of efficiency.

Mercury (Hg) is a highly toxic heavy metal for all organisms. In the present study, the mitigative role of 190 mg/L and 380 mg/L doses of green tea extract (GTex) against mercury(II) chloride (HgCI₂)-induced toxicity was evaluated in Allium cepa L. For this aim, selected physiological, genotoxicity, and biochemical parameters as well as meristematic cell injuries in the roots were investigated. Ratios of catechin and caffeine in GTex were determined by HPLC analysis. Also, free radical scavenging activity of GTex was tested against superoxide and hydrogen peroxide radicals. As a result of HgCI₂ application, germination percentage, root elongation, weight gain, and mitotic index (MI) declined, while the frequency of micronucleus (MN), chromosomal abnormalities (CAs), and meristematic cell damages increased. HgCI₂ administration also led to a significant increase in malondialdehyde content, superoxide dismutase, and catalase activities which are signs of oxidative stress. On contrary, applications of GTex together with HgCI₂ reduced HgCI₂-induced adverse effects in all parameters in a dose-dependent manner. Antioxidant components in GTex were listed as caffeine, epigallocatechin gallate, epigallocatechin, epicatechin gallate, and catechin according to their abundance. GTex exhibited a strong scavenging ability in the presence of superoxide and hydrogen peroxide radicals. The present study revealed the strong protective capacity of GTex against HgCI₂-induced toxicity in A. cepa owing to its high antioxidant content with a multifaceted perspective. With this study, a reliable starting point was established for future studies investigating the more common and diverse use of GTex against toxic substances.

Nano zero valent iron (nZVI) is an excellent adsorbent/reductant with wide applicability in remediation of persistent contaminants in soil, water and groundwater aquifers. There are concerns about its environmental fate, agglomeration, toxicity and stability in the air. Several modification methods have applied chistosan, green tea, carboxyl methyl cellulose and other coating substances to ensure production of nZVI with excellent air stability and effectiveness. The synthesis of a novel green nZVI (gNZVI) with Harpephyllum caffrum leaf extracts was successfully executed in the current study. Production of gNZVI involved the simultaneous addition of an optimum amount of the NaBH₄ and H. caffrum extract to FeCl₃ in an inert environment (Nitrogen). The solution was stirred for 30 min, washed with dilute ethanol (50%) and freeze dried. This procedure offered the best option for the synthesis of gNZVI in terms of nontoxic and inexpensive choice of stabiliser/reductant. Systematic characterisations using TGA, TEM, SEM, XRD, FT-IR and XPS confirmed the synthesis of crystalline, stable, reactive, well-dispersed and predominantly 50 nm diameter sized gNZVI compared to the conventionally synthesised nZVI which is 65 nm. The activity testing using Orange II sodium salt (OR2) confirmed the effectiveness of the synthesised gNZVI as an excellent Fenton catalyst with 65% degradation of 20 ppm OR2 dye in 1 h reaction time.