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A novel clean production approach to utilize crop waste residues as co-diet for mealworm (Tenebrio molitor) biomass production with biochar as byproduct for heavy metal removal Полный текст
2019
Yang, Shanshan | Chen, Yi-di | Zhang, Ye | Zhou, Hui-Min | Ji, Xin-Yu | He, Lei | Xing, De-Feng | Ren, Nan-Qi | Ho, Shih-Hsin | Wu, Weimin
Proper management of waste crop residues has been an environmental concern for years. Yellow mealworms (larvae of Tenebrio molitor Linnaeus, 1758) are major insect protein source. In comparison with normal feed wheat bran (WB), we tested five common lignocellulose-rich crop residues as feedstock to rear mealworms, including wheat straw (WS), rice straw (RS), rice bran (RB), rice husk (RH), and corn straw (CS). We then used egested frass for the production of biochar in order to achieve clean production. Except for WS and RH, the crop residues supported mealworms’ life activity and growth with consumption of the residues by 90% or higher and degraded lignin, hemicellulose and cellulose over 32 day period. The sequence of degradability of the feedstocks is RS > RB > CS > WS > RH. Egested frass was converted to biochar which was tested for metal removal including Pb(II), Cd(II), Cu(II), Zn(II), and Cr(VI). Biochar via pyrolysis at 600 °C from RS fed frass (FRSBC) showed the best adsorption performance. The adsorption isotherm fits the Langmuir model, and kinetic analysis fits the Pseudo-Second Order Reaction. The heavy metal adsorption process was well-described using the Intra-Particle Diffusion model. Complexation, cation exchange, precipitation, reduction, deposition, and chelation dominated the adsorption of the metals onto FRSBC. The results indicated that crop residues (WS, RS, RB, and CS) can be utilized as supplementary feedstock along with biochar generated from egested frass to rear mealworms and achieve clean production while generating high-quality bioadsorbent for environment remediation and soil conditioning.
Показать больше [+] Меньше [-]Facile self-assembly synthesis of γ-Fe2O3 /graphene oxide for enhanced photo-Fenton reaction Полный текст
2019
Wang, Feifei | Yu, Xiaolin | Ge, Maofa | Wu, Sujun | Guan, Juan | Tang, Junwang | Wu, Xiao | Ritchie, R. O. (Robert O.)
A novel self-assembly method was developed to prepare a γ-Fe₂O₃/graphene oxide (GO) heterogeneous catalyst that showed excellent synergy between photocatalysis and Fenton-like reactions. The γ-Fe₂O₃/GO catalyst prepared on the iron plates demonstrated efficient and reproducible catalytic activities for water treatment. It takes only 80 min to degrade 50 mg L⁻¹ methylene (MB) completely, which is the main non-biodegradable dye in wastewater from the textile industry. The heterogeneous catalyst is stable over a wide range of pH (from 2.0 to 10.2) for MB degradation, and can be easily extracted from solution and repeatedly used with little loss of catalytic activity. The high activity and stability of the catalyst system can be attributed to charge separation between γ-Fe₂O₃ and GO, which could accelerate Fenton-like process and photocatalysis. In addition, the dominant reactive oxidant species responsible for the MB degradation, including the hydroxyl radicals (•OH) and holes (h⁺), were trapped on the surface of the γ-Fe₂O₃/GO composite, as proved by a free-radical quenching experiment. The γ-Fe₂O₃/GO heterogeneous catalyst could potentially provide a solution for removal of non-biodegradable dyes from wastewater in the textile industry.
Показать больше [+] Меньше [-]Effects of perinatal exposure to BPA, BPF and BPAF on liver function in male mouse offspring involving in oxidative damage and metabolic disorder Полный текст
2019
Meng, Zhiyuan | Tian, Sinuo | Yan, Jin | Jia, Ming | Yan, Sen | Li, Ruisheng | Zhang, Renke | Zhu, Wentao | Zhou, Zhiqiang
Bisphenols (BPs) are common environmental pollutants that are ubiquitous in the natural environment and can affect human health. In this study, we explored the effects of perinatal exposure to BPA, BPF and BPAF on liver function involving in oxidative damage and metabolic disorders in male mouse offspring. We found that BPA exposure impairs the antioxidant defense system, increases lipid peroxidation, and causes oxidative damage in the liver. Furthermore, the levels of 13 metabolites were significantly altered following BPA exposure. We found that BPF exposure significantly increased the expression and activity of CAT, suggesting disturbances in the antioxidant defense system. Moreover, BPF exposure led to metabolic disorders in the liver due to changes in the levels of 8 key metabolites. Exposure to BPAF caused no negative effects on oxidative damage, but altered the levels of β-glucose and glycogen. In summary, perinatal exposure to BPA, BPF and BPAF differentially influence oxidative damage and metabolic disorders in the livers of male mouse offspring. The impact of early life exposure to BPs now warrants future investigations.
Показать больше [+] Меньше [-]Assessment of the sources and inflow processes of microplastics in the river environments of Japan Полный текст
2019
Kataoka, Tomoya | Nihei, Yasuo | Kudou, Kouki | Hinata, Hirofumi
The numerical and mass concentrations of microplastics collected at 36 sites on the surfaces of 29 Japanese rivers were mapped and compared with four basin characteristics (basin area, population density, and urban and agricultural ratios) and six water quality parameters (pH, biochemical oxygen demand (BOD), suspended solids (SS), dissolved oxygen (DO), total nitrogen (T-N), and total phosphorus (T-P)) in each river basin. Microplastics were found in 31 of the 36 sites, indicating that some plastics fragment into small pieces before reaching the ocean. The microplastic concentrations are significantly correlated with urbanisation and population density, indicating that the microplastic concentrations in the river depend on human activities in the river basin. Furthermore, we found a significant relationship between the numerical and mass concentrations and BOD, which is an environmental indicator of river pollution. This result demonstrates that microplastic pollution in river environments has progressed more in polluted rivers with poor water quality than in rivers with good water quality, leading to the conclusion that the sources and inflow processes of microplastics in river environments are similar to those of other pollutants. Our findings can help identify potential sources (i.e., point and non-point sources) of fragmented microplastics to improve waste management in Japan and model the transport fluxes of fragmented microplastics in Japanese rivers using water quality parameters and basin characteristics.
Показать больше [+] Меньше [-]Association of serum levels of 4-tertiary-octylphenol with cardiovascular risk factors and carotid intima-media thickness in adolescents and young adults Полный текст
2019
Lin, Chien-Yu | Hwang, Yi-Ting | Chen, Pau-Chung | Sung, Fung-Chang | Su, Ta-Chen
In the family of alkylphenolic compounds, 4-tertiary-Octylphenol (4-t-OP) is extensively used in many products. In animal and in vitro studies, 4-t-OP exposure has been linked to cardiovascular disease (CVD) risk factors; however, there are no previous human epidemiological studies. In this study, 886 subjects were recruited from a cohort of Taiwanese adolescents and young adults to study the relationship between serum levels of 4-t-OP, CVD risk factors, and common carotid artery intima-media thickness (CIMT). The geometric mean (SD) 4-t-OP concentration was 32.52 (1.71) ng/mL. We found that serum levels of 4-t-OP were negatively associated with markers of glucose homeostasis (insulin, homeostasis model assessment of insulin resistance (HOMA-IR) and homeostasis model assessment of β-cell function (HOMA-β)), z score of body mass index (BMI z score) and CIMT but were positively associated with lipid profiles (high density lipoprotein cholesterol (HDL-C), Apolipoprotein A1). A one-unit elevation in natural log-transformed 4-t-OP (ng/mL) was negatively correlated with CIMT (mm) (β = −0.029, SE = 0.003, P < 0.001) in multiple linear regression analyses. The relationship between 4-t-OP and CIMT remained the same in all subgroups or if bisphenol A (BPA) was considered a covariate. In this study, we observed that higher levels of 4-t-OP levels were negatively correlated with markers of glucose homeostasis, BMI z score, and CIMT; positively correlated with lipid profiles (HDL-C and apolipoprotein A) in this cohort. Future research on exposure to 4-t-OP and CVD risk factors is warranted.
Показать больше [+] Меньше [-]A PAH-degrading bacterial community enriched with contaminated agricultural soil and its utility for microbial bioremediation Полный текст
2019
Lü, Chao | Hong, Yang | Liu, Juan | Gao, Yanzheng | Ma, Zhao | Yang, Bing | Ling, Wanting | Waigi, Michael Gatheru
A bacterial community was enriched with polycyclic aromatic hydrocarbons (PAHs) polluted soil to better study PAH degradation by indigenous soil bacteria. The consortium degraded more than 52% of low molecular weight and 35% of high molecular weight (HMW) PAHs during 16 days in a soil leachate medium. 16S rRNA gene high-throughput sequencing and quantitative polymerase chain reaction analyses for alpha subunit genes of ring-hydroxylating-dioxygenase (RHDα) suggested that Proteobacteria and Actinobacteria at the phylum level, Pseudomonas, Methylobacillus, Nocardioides, Methylophilaceae, Achromobacter, Pseudoxanthomonas, and Caulobacter at the generic level were involved in PAH degradation and might have the ability to carry RHDα genes (nidA and nahAc). The community was selected and collected according to biomass and RHDα gene contents, and added back to the PAH-polluted soil. The 16 EPA priority PAHs decreased from 95.23 to 23.41 mg kg⁻¹ over 35 days. Compared with soil without the introduction of this bacterial community, adding the community with RHDα genes significantly decreased soil PAH contents, particularly HMW PAHs. The metabolic rate of PAHs in soil was positively correlated with nidA and nahAc gene contents. These results indicate that adding an indigenous bacterial consortium containing RHDα genes to contaminated soil may be a feasible and environmentally friendly method to clean up PAHs in agricultural soil.
Показать больше [+] Меньше [-]The association between prenatal cadmium exposure and birth weight: A systematic review and meta-analysis of available evidence Полный текст
2019
Huang, Shouhe | Kuang, Jie | Zhou, Fankun | Jia, Qiyue | Lu, Qi | Feng, Zhang | Yang, Wei | Fan, Guangqin
We conducted a meta-analysis to evaluate the association between prenatal cadmium (Cd) exposure and birth weight. PubMed, Embase, China National Knowledge Infrastructure (CNKI), and Wanfang databases were searched for studies published before March 2019. We used a model-based method, standardizing effect size from linear regression models to include a maximum number of studies during our quantitative evaluations. As a result, 11 articles from the general population, containing 10 birth cohorts and one cross-sectional study, were included. Our meta-analysis demonstrated that a 50% increase of maternal urine Cd (UCd) would be associated with a 6.15 g decrease in neonatal birth weight (β = −6.15 g, 95% CI: −10.81, −1.49) as well as a 50% increase of maternal blood Cd (BCd) would be associated with an 11.57 g decrease (β = −11.57 g; 95% CI: −18.85, −4.30). Stratified analysis of UCd data indicated that the results of female newborns were statistically significant (β = −8.92 g, 95% CI: −17.51, −0.34), as was the first trimester (β = −11.34 g, 95% CI: −19.54, −3.14). Furthermore, increased UCd levels were associated with a higher rate of low birth weight (LBW) risk (OR = 1.12, 95% CI: 1.03, 1.22). This meta-analysis demonstrated that elevated maternal Cd levels are associated with decreased birth weight and higher LBW risk.
Показать больше [+] Меньше [-]Cardiogenesis impairment promoted by bisphenol A exposure is successfully counteracted by epigallocatechin gallate Полный текст
2019
Lombó, Marta | González-Rojo, Silvia | Fernández-Díez, Cristina | Herráez, María Paz
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.
Показать больше [+] Меньше [-]A critical review on the application of the National Sanitation Foundation Water Quality Index Полный текст
2019
Noori, Roohollah | Berndtsson, Ronny | Hosseinzadeh, Majid | Adamowski, Jan Franklin | Abyaneh, Maryam Rabiee
Many studies have employed the National Sanitation Foundation Water Quality Index (NSFWQI) with non-original rather than originally defined parameters of the model, particularly when incorporating fecal coliform (FC), total solids, and total phosphates as inputs. For this reason, this study aimed to perform a critical review on the application of the NSFWQI to explore the amount of change that can be expected when users employed non-original parameters (such as orthophosphate and total dissolved solids/total suspended solids instead of total phosphorous and total solids, respectively), or different units (FC based on the maximum probable number (FC-MPN) rather than the colony forming unit (FC-CPU)). To demonstrate the influence of originally defined inputs on NSFWQI results, various scenarios were investigated. These scenarios were generated using different possible inputs to the NSFWQI, altering the FC, total solids, and total phosphorous parameters obtained from the monitoring stations of the Sefidroud River in Iran. Considerable differences were observed in the NSFWQI values when using orthophosphate and total suspended solids, instead of the originally defined data (i.e., total phosphorous and total solids), in the model (first scenario). In this case, the number of stations with “good” water quality increased from one to seven when compared with the first scenario results. In addition, unlike the results of the first scenario, none of the stations were classified as class IV (i.e., “bad” water quality status). However, the results of the implemented scenarios presented a more favorable water quality status than those obtained using the first scenario (except the second scenario which included FC-MPN rather than FC-CFU). Using total dissolved solids instead of total solids and FC-MPN rather than FC-CPU, resulted in fewer changes. In both cases, the average of the NSFWQI values in the river classed all stations as “medium” and “bad” water quality for the wet and dry seasons, respectively. Proper application of NSFWQI is important to provide high quality results for evaluation of water bodies, particularly when incorporating total solids and total phosphorous as inputs.
Показать больше [+] Меньше [-]Dynamics, biodegradability, and microbial community shift of water-extractable organic matter in rice–wheat cropping soil under different fertilization treatments Полный текст
2019
Hui, Cai | Liu, Bing | Wei, Ran | Jiang, Hui | Zhao, Yuhua | Liang, Yongchao | Zhang, Qichun | Xu, Ligen
Although fertilization plays an important role in determining the contents of soil dissolved organic matters or water-extractable organic matter (DOM, WEOM), knowledge regarding the dynamics, biodegradability, and microbial community shifts of WEOM in response to different fertilization treatments is very limited, particularly in rice–wheat cropping soil. Thus, in the present study, we performed biodegradation experiments using WEOM extracted from samples of soil that had been subjected to four different fertilization treatments: unfertilized control (CK), chemical fertilizer (CF), 50% chemical fertilizer plus pig manure (PMCF), and 100% chemical fertilizer plus rice straw (SRCF). UV spectrum and fluorescence 3D excitation–emission matrix analyses applied to investigate the chemical composition of WEOM revealed that all examined WEOMs were derived from microbial activity and the dominant portion comprised humic acid-like compounds. After the incubation, 31.17, 31.63, 43.47, and 33.01% of soil WEOM from CK, CF, PMCF, and SRCF treatments, respectively, were biodegraded. PMCF- derived WEOM had the highest biodegradation rate. High-throughput sequencing analyses performed to determine the microbial community before and after the incubation indicated that Sphingomonas, Bacillus, and Flavisolibacter were the predominant bacterial genera in the original inoculum derived from the four fertilization treatments. Following biodegradation, we observed that the dominant bacteria differed according to fertilization treatments: Curvibacter (43.25%) and Sphingobium (10.47%) for CK, Curvibacter (29.68%) and Caulobacter (20.00%) for CF, Azospirillum (23.68%) and Caulobacter (13.29%) for PMCF, and Ralstonia (51.75%) for SRCF. Canonical correspondence analysis revealed that, shifts in the microbial community were closely correlated with pH and specific UV absorbance at 254 nm. We speculated that the inherent traits of different WEOM and the properties of soil solutions under different fertilization treatments shaped the soil microbial community structure, thereby influencing the biodegradation of WEOM.
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