Toxicity Reduction of Municipal Wastewater by Anaerobic-anoxic-oxic Process

Objective This study was conducted to optimize the operational parameters of anaerobic-anoxic-oxic （A^2/O） processes to reduce the toxicity of municipal wastewater and evaluate its ability to reduce toxicity. Methods A luminescent bacterium toxicity bioassay was employed to assess the toxicity of influent and effluent of each reactor in the A2/O system. Results The optimum operational parameters for toxicity reduction were as follows： anaerobic hydraulic retention time （HRT） = 2.8 h, anoxic HRT = 2.8 h, aerobic HRT = 6.9 h, sludge retention time （SRT） = 15 days and internal recycle ratio （IRR） = 100%. An important toxicity reduction （%） was observed in the optimized A2/O process, even when the toluene concentration of the influent was 120.7 mg·L^-1. Conclusions The toxicity of municipal wastewater was reduced significantly during the A^2/O process. A^2/O process can be used for toxicity reduction of municipal wastewater under toxic-shock loading.

Review of Modern Research on Toxicity of Traditional Chinese Medicine Aconm Lateralis Radix Praeparaia

The traditional Chinese medicine Aconm Lateralis Radix Praeparaia(Fuzi)is pungent and sweet in taste,hot in nature,and has high toxicity.It governs the meridians of the heart,kidney and spleen.It has the functions of restoring yang to save from collapse,dispersing cold and removing dampness,and warming the middle to relieve pain.It is often used for the treatment of yang collapse,cold limbs,weak pulse,heart yang deficiency,heart pain due to chest impediment,abdominal cold-pain,kidney yang deficiency,impotence and cold in womb,and syndrome of exogenous disease due to yang deficiency,etc.Its great yang qi and strong medicinal properties often bring about toxic and adverse effects.However,after processing or combination with other medicinal materials,the effects of Aconm Lateralis Radix Praeparaia are quite different.Not only the toxicity is greatly reduced,but also the curative effects are strengthened.Through searching related literature,this paper reviewed the researches about the toxicity reduction and curative effect improvement of Aconm Lateralis Radix Praeparaia,in order to provide a certain theoretic reference for future further research of Aconm Lateralis Radix Praeparaia.

The riddles of number nine in Chinese medicine processing method

The“nine cycles of steaming and shining”,“nine making”,“nine turns”and“nine cycles of calcining and quenching”methods that are recorded and used since ancient times are merely one aspect of the unique processing methods of traditional Chinese medicine.Inducing the Chinese medicine processing method“nine cycles of steaming and shining”from historical review and summarizing the practical wisdom based on the canonical aspects of traditional Chinese medicine and the experiences of ancient Chinese medicine sages to promote the new development of traditional Chinese medicine.After the long-term and multiple“nine”processing,the materials of traditional Chinese medicine exhibit significant beneficial changes in terms of taste,efficacy,and chemical composition contents,thus emphasizing that Chinese medicine processing plays a significant role in their efficacy enhancement and toxicity reduction.Heshouwu(Polygoni Multiflori Radix),Dihuang(Rehmanniae Radix),Huangjing(Rhizoma Polygonati),Dahuang(Radix et Rhizoma Rhei),and Xixiancao(Herba Siegesbeckiae)are representatives of Chinese medicinal materials prepared using the“nine-system”processing method.This review discovers the aim and the molecular mechanism of“nine”processing of the abovementioned herbs from the viewpoints of modern pharmacochemistry and pharmacology to provide a theoretical support for the“nine”processing method of traditional Chinese medicine and to promote the international market of traditional Chinese medicine.

Study on the compatibility principle of Wutou Decoction based on network pharmacology

Objective To investigate the underlying drug enhancement mechanisms of the Chuanwu(Aconiti Radix)and Huangqi(Astragali Radix)combination and toxicity reduction of Chuan-wu combined with Gancao(Glycyrrhizae Radix et Rhizoma)in Wutou Decoction(乌头汤,WTD),and to elucidate the compatibility principle.Methods The active compounds and potential effective targets of the selected combinations were retrieved from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP)and Traditional Chinese Medicines Integrated Database(TCMID).The toxicity of Chuanwu(Aconiti Radix)was investigated by selecting all five toxic compounds from the literature and the TCMSP database,and obtaining their targets through SwissTargetPrediction.Targets related to rheumatoid arthritis(RA)were searched using Dis-GeNET,GenCards,and Online Mendelian Inheritance in Man(OMIM).Mutual targets between the drug pairs and RA were selected as potential RA therapy targets.The medicinally active compound-target network was constructed using Cytoscape 3.9.0.Gene ontology(GO)term enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrich-ment were performed using the Database for Annotation,Visualization,and Integrated Dis-covery(DAVID)platform.Results We obtained 191 active compound targets for Gancao(Glycyrrhizae Radix et Rhizoma),171 for Huangqi(Astragali Radix),and 103 for Chuanwu(Radix Aconiti)(hypo-aconitine’s target was obtained through literature and SwissTargetPrediction).A total of 5872 genes were obtained for RA.A drug-active compound-target network involving 13 effect-en-hancing and nine toxicity reduction targets was constructed.PGR was the main effect en-hancement target,and KCNH2 was the main toxicity reduction target.The effect-enhancing targets were related to 23 GO terms(such as positive regulation of transcription from RNA polymerase II promoter,steroid hormone-mediated signaling pathway,plasma membrane,and protein binding)(P<0.01),and 13 KEGG pathways related to synergism[such as estro-gen signaling pathway,cholinergic synapse,and phosphatidylinositol 3-kinase/protein kinase B(PI3K/Akt)signaling pathway].The toxicity reduction targets were related to 28 GO terms(mainly involes G-protein coupled receptor signaling pathway,plasma membrane,and drug binding)(P<0.01),and five KEGG pathways related to toxicity reduction(cholinergic syn-apse,calcium signaling pathway,regulation of actin cytoskeleton,neuroactive ligand-recept-or interaction,and serotonergic synapse).Conclusion The combination of Chuanwu(Aconiti Radix)and Huangqi(Astragali Radix)plays an important effect-enhancing role in WTD and involves the estrogen and PI3K/Akt sig-naling pathways,with PGR as the core.The Chuanwu(Aconiti Radix)and Gancao(Gly-cyrrhizae Radix et Rhizoma)combination decreases toxicity in WTD and is associated with the cholinergic synapse and calcium signaling pathways,with KCNH2 as the core.

Sunlight-driven reduction of silver ion to silver nanoparticle by organic matter mitigates the acute toxicity of silver to Daphnia magna

Due to the unique antibacterial activities, silver nanoparticles（AgNPs） have been extensively used in commercial products. Anthropogenic activities have released considerable AgNPs as well as highly toxic silver ion（Ag^＋） into the aquatic environment.Our recent study revealed that ubiquitous natural organic matter（NOM） could reduce Ag^＋to Ag NP under natural sunlight. However, the toxic effect of this process is not well understood. In this work, we prepared mixture solution of Ag^＋and AgNPs with varied Ag^＋% through the sunlight-driven reduction of Ag^＋by NOM and investigated the acute toxicity of the solutions on Daphnia magna. Formation of AgNPs was demonstrated and characterized by comprehensive techniques and the fraction of unconverted Ag^＋was determined by ultrafiltration-inductively coupled plasma mass spectrometry determination. The formation of AgNPs enhanced significantly with the increasing of solution p H and cumulative photosynthetically active radiation of sunlight. The toxicity of the resulting solution was further investigated by using freshwater crustacean D. magna as a model and an 8 hr-median lethal concentration（LC50） demonstrated that the reduction of Ag^＋by NOM to AgNPs significantly mitigated the acute toxicity of silver. These results highlight the importance of sunlight and NOM in the fate, transformation and toxicity of Ag^＋and AgNPs,and further indicate that the acute toxicity of AgNPs should be mainly ascribed to the dissolved Ag^＋from AgNPs.

Silver nanoparticles tolerant bacteria from sewage environment

Silver nanoparticle （SNP） is a threat to soil, water and human health. Protection of environment from silver nanoparticles is a major concern. A sewage isolate, Bacillus pumilus treated with SNPs showed similar growth kinetics to that without nanoparticles. A reduction in the amount of exopolysaccharides was observed after SNPs - B. pumilus culture supernatant interaction. The Fourier transform infrared spectroscopy （FT-IR） peaks for the exopolysaccharides extracted from the bacterial culture supernatant and＇the interacted SNPs were almost similar. The exopolysaccharide capping of the SNPs was confirmed by UV-Visible, FT-IR and X-ray diffraction analysis. The study of bacterial exopolysaccharides capped SNPs with E. coli, S. aureus and M. luteus showed less toxicity compared to uncoated SNPs. Our studies suggested that the capping of nanopartieles by bacterially produced exopolysaccharides serve as the probable mechanism of tolerance.

Washing out heavy metals from contaminated soils from an iron and steel smelting site

Washing is a promising method for separating contaminants bound to the particles of soil ex-situ by chemical mobilization. Laboratory batch washing experi- ments were conducted using deionized water and varying concentrations of oxalic acid, citric acid, tartaric acid, acetic acid, hydrochloric acid and ethylenediaminetetra acetic acid （EDTA） to assess the efficiency of using these chemicals as washing agents and to clean up heavy metals from two heavily polluted soils from an iron and streel smelting site. The toxicity reduction index and remediation costs were analyzed, and the results showed that the soils were polluted with Cd, Pb and Zn. Hydrochloric acid and EDTA were more efficient than the other washing agents in the remediation of the test soils. The maximum total toxicity reduction index showed that 0.5 mol·L^-1 hydro- chloric acid could achieve the remediation with the lowest costs.