Removal characteristics of high concentration glyphosate in bioretention cells.

Glyphosate, as one of the most widely used pesticides, has been found in rainwater runoff. A bioretention cell with two types of fillers was constructed to explore removal of glyphosate in runoff an transformation of glyphosate in the filler. The type of filler had a significant impact on adsorption and degradation of glyphosate in the bioretention cell. The glyphosate removal efficiencies of coal cinder modified loess (CLB) and zeolite modified loess (ZLB) were 33.13-99.7% and 55.04-99.7%, respectively. Conversion of glyphosate in the bioretention cell occurred mainly in the upper layer of the filler. When the concentration of glyphosate in the runoff was 0.25 or 0.5 mg/L, the concentration of glyphosate degradation products at the two outlets along the way was as much as 26 times higher than that at the lowest outlet. Rainfall events promoted the migration of glyphosate and its degradation products within the filler. Glyphosate and its degradation products in ZLB were mainly distributed at 15 and 25 cm deep in the filler layer, while the highest concentrations in CLB were at 5 and 35 cm. Discontinuous runoff into the bioretention cell leads to continuous leaching and adsorption of glyphosate in the bioretention cell until complete degradation occurs.

Nitrogen removal performance of bioretention cells under polyethylene (PE) microplastic stress.

The use of bioretention cells as a stormwater control measure allows stormwater runoff to be collected and filtered, effectively removing microplastics and other pollutants from stormwater. This study investigated the effect of polyethylene microplastics (PE-MPs) retention on the bioretention cell, in terms of denitrification performance and microbial community structure. Four PE-MP exposures were compared at different concentrations of 0, 250, 500 and 1000 mg/L under alternating dry and wet period conditions. Results showed that the removal efficiency reduced by 14.99%, 28.37% and 18.59% with PE-MP concentrations of 250, 500 and 1000 mg/L. The NO3--N removal efficiency increased by 36.19%, 20.19% and 35.39%. After 8 days of dry conditions, the NO3--N removal efficiencies of the bioretention cells were reduced by 36.66%, 46.86% and 31.11% compared to those after 2 days of dry conditions. Microbial sequencing results indicated that the accumulation of PE-MPs changed the microbial community structure within the bioretention cell filler material, promoting the growth of bacteria such as Actinobacteria, Bacteroidetes and Firmicutes. Furthermore, PE-MPs reduced the relative abundance of nitrifying bacteria (e.g. Nitrospira) within the bioretention cell and promoted denitrifying bacteria (e.g. Dechloromonas and Hydrogenophaga), along with numerous other genera such as Azotobacter and Nocardia.

Influence of double-layer filling structure on nitrogen removal and internal microbial distribution in bioretention cells.

The nitrogen removal effect of traditional bioretention cells on runoff rainwater is not stable. The nitrogen removal effect of bioretention cells can be improved by setting up a layered filling structure, but the effect of changes in filling structure on the nitrogen removal process and microbial community characteristics is still unclear. Two types of porosity fillers were set up in the experiment, and a homogeneous bioretention cell and three bioretention cells with layered fillers were constructed by changing the depth range of the upper and lower layers to analyze the influence of the pore variation of different depth fillers on the nitrogen removal process and microbial community characteristics. The experimental results showed that, compared with the homogeneous filing structure, the layered filling structure can strengthen the adsorption of NH4+-N and the conversion of NO3--N, so as to increase the removal rates of NH4+-N and NO3--N by 20.71-81.56% and 9.25%-78.19%, respectively. Although the low porosity filler structure will reduce the nitrification activity and urease activity by 48.63%-66.68% and 8.00%-20.64% respectively, it can increase the denitrification activity by 19.14%-31.92%, thus significantly reducing the nitrate content in the filler. The low porosity filler structure can affect the growth and reproduction of various phylum bacteria such as Proteobacteria, Chloroflexi, Acidobacteria, and genus bacteria such as Nitrospira, Ellin6067, Rhizobacter, Pseudomonas, which can improve the diversity and richness of microorganisms.

The protective effect of quinoa on the gastric mucosal injury induced by absolute ethanol.

BACKGROUND: Gastric mucosal injury caused by ethanol is a common gastrointestinal disease. Quinoa (Chenopodium quinoa Willd.), as a nutrient-rich grain, plays a significant role in preventing and treating gastric mucosal damage. The present study aimed to explore the protective effect of quinoa on alcohol-induced gastric mucosal damage and its possible mechanism. RESULTS: The ethanol-induced gastric mucosal injury rat model was used for in vivo experiments and H2 O2 -induced GES-1 cells for in vitro experiments to elucidate the protective effect of quinoa. The results show that quinoa water extract can increase the superoxide dismutase level and decrease the malondialdehyde level in vitro and in vivo. Furthermore, quinoa also reduced the bleeding point and bleeding area in rats with ethanol-induced gastric mucosal injury and improved gastric histopathological changes. H2 O2 significantly increased the levels of inflammatory factors in GES-1 cells, which were markedly ameliorated by quinoa water extract. Likewise, quinoa water extract regulated the protein expression levels of Nrf2, Keap1, HO-1, p-IKK, and p-NF-κB through Nrf2 and nuclear factor-κB signaling pathways, reducing the production of oxidative stress and inflammation, thereby repairing the damaged gastric mucosa. CONCLUSION: The findings of this study demonstrated that quinoa shows protective effect against ethanol-induced gastric mucosal injury through its anti-inflammatory and anti-oxidant effects. We propose that our research will provide a reference for quinoa as a functional food. © 2022 Society of Chemical Industry.

The Pharmacological Effects of Lutein and Zeaxanthin on Visual Disorders and Cognition Diseases.

Lutein (L) and zeaxanthin (Z) are dietary carotenoids derived from dark green leafy vegetables, orange and yellow fruits that form the macular pigment of the human eyes. It was hypothesized that they protect against visual disorders and cognition diseases, such as age-related macular degeneration (AMD), age-related cataract (ARC), cognition diseases, ischemic/hypoxia induced retinopathy, light damage of the retina, retinitis pigmentosa, retinal detachment, uveitis and diabetic retinopathy. The mechanism by which they are involved in the prevention of eye diseases may be due their physical blue light filtration properties and local antioxidant activity. In addition to their protective roles against light-induced oxidative damage, there are increasing evidences that L and Z may also improve normal ocular function by enhancing contrast sensitivity and by reducing glare disability. Surveys about L and Z supplementation have indicated that moderate intakes of L and Z are associated with decreased AMD risk and less visual impairment. Furthermore, this review discusses the appropriate consumption quantities, the consumption safety of L, side effects and future research directions.