Petroleum hydrocarbon pollutants are difficult to be degraded, and bioremediation has received increasing attention for remediating the hydrocarbon polluted area. This review started by introducing the interphase adaptation and transport process of hydrocarbon by microbes. Subsequently, the advances made in the identification of hydrocarbon-degrading strains and genes as well as elucidation of metabolic pathways and underpinning mechanisms in the biodegradation of typical petroleum hydrocarbon pollutants were summarized. The capability of wild-type hydrocarbon degrading bacteria can be enhanced through genetic engineering and metabolic engineering. With the rapid development of synthetic biology, the bioremediation of hydrocarbon polluted area can be further improved by engineering the metabolic pathways of hydrocarbon-degrading microbes, or through design and construction of synthetic microbial consortia.
Bacteria/genetics* ; Biodegradation, Environmental ; Hydrocarbons ; Petroleum ; Petroleum Pollution/analysis* ; Soil Microbiology ; Soil Pollutants

The effects of four natural organic soil amendments on the quality and pesticide residues of Panax notoginseng were investigated through field experiments and the suitable dosage ratio of each soil amendment was selected to provide a new idea for the pollution-free cultivation of P. notoginseng. The four natural organic soil amendments used in this study were Jishibao, Jihuo, Fudujing, and omnipotent nutrients, which were produced by mixed fermentation of aboveground parts of different plants, biological waste residue, and biochar. During the experiments, only four soil amendments were applied to P. notoginseng instead of any pesticides and fertilizers. The experiment was designed as four factors and three levels. There were three dosage gradients(low, medium, and high) for Jishibao(A), Jihuo(B), Fudujing(C), and omnipotent nutrients(D). When the dosage of one soil amendment changed, the do-sage of the other soil amendments remained medium. There were 10 groups in addition to the soil amendment-free group as control(CK). The results showed that the four soil amendments could significantly improve the growth environment of P. notoginseng and increase the seedling survival rate and saponin content of P. notoginseng. The seedling survival rates of the treatment groups increased by 8.24%-30.05% as compared with the control group. Furthermore, the content of pesticide residues in P. notoginseng was too low to be detected, and that of heavy metals in P. notoginseng was far lower than the specified content in the Chinese Pharmacopoeia(2020). The optimal effect was achieved at medium dosage for all the soil amendments with the highest content of saponins, high seedling survival rate, and significantly reduced heavy metals, such as lead, cadmium, arsenic, and mercury.
Arsenic ; Metals, Heavy/analysis* ; Panax notoginseng ; Soil ; Soil Pollutants/analysis*

To investigate the degradation of polycyclic aromatic hydrocarbons (PAHs) and the changes of rhizosphere microorganisms in the rhizosphere soil of Leymus chinensis during the remediation of PAHs contaminated soil by Comamonas testosteroni (C.t)-assisted Leymus chinensis, we evaluated the removal of PAHs in the rhizosphere of Leymus chinensis using gas chromatography-mass spectrometry (GC-MS), analyzed the bacterial community and the diversity in Leymus chinensis rhizosphere soil by high-throughput sequencing technology, characterized the correlation among PAHs degradation and bacterial community components performing redundancy analysis (RDA) and network analysis, and predicted PAHs degradation potential via PICRUSt software in this paper. The degradation of PAHs in the rhizosphere of Leymus chinensis was promoted, the abundance and diversity of bacteria and the correlation among bacteria and PAHs were changed, and the degradation potential of PAHs in Leymus chinensis rhizosphere soil was enhanced in the later stage of phytoremediation (60-120 d) due to the incorporation of C.t. The accelerated degradation of three PAHs (Nap, Phe, BaP) was accompanied by the differ abundance and correlation of Proteobacteria (Sphingomonas, MND1, Nordella), Actinomycetes (Rubrobacter, Gaiella), Acidobacteria (RB41) and Bacteroides (Flavobacterium) affected by C.t. The results provide new insight into the microorganism choices for microbial assisted plant remediation of soil PAHs and the mechanisms of enhanced PAHs degradation via the combination of Comamonas testosteroni engineering bacteria and plants.
Biodegradation, Environmental ; Comamonas testosteroni/genetics* ; Polycyclic Aromatic Hydrocarbons/analysis* ; Rhizosphere ; Soil ; Soil Microbiology ; Soil Pollutants

Environmental Monitoring ; Groundwater ; Refuse Disposal ; Soil ; Waste Disposal Facilities ; Water Pollutants, Chemical/analysis*

In order to understand the pollution of heavy metals in Guizhou soil planting Eucommia ulmoides,the paper has determined the contents of five heavy metals respectively( Cu,Cd,Pb,Hg and As) by atomic absorption spectrophotometry. The soil environmental quality by single factor pollution index was evaluated,nemerow integrated pollution index and potential ecological risk index,the correlation of 5 heavy metals was analyzed and the relationship between heavy medals content and p H value was discussed. The results showed that: ①The soils of LP,SB and ZA-2 had low heavy metals content,LP soil met the first national standard,and other soils met the second national standard; ②The soils of LP,ZA-1 and ZA-2 were all in a clean state,while HX and BZ-1 were in a light pollution state,and the pollution degree was Cu>Pb>As>Cd>Hg; ③The soil of BZ-2 was light warning( medium ecological risk),the soils of HX,BZ-1 and MT were early warning( low ecological risk),the main warning source was Cu and Pb,and the rest were no warning( no ecological risk); ④Cd and As were positively correlated with Pb and Hg,and Cd,Pb and As were positively correlated with p H. The research showed that the soils of LP,SB,ZA-1 and ZA-2 were clean and could be used for E. ulmoides to continue planting,the soils of HX,MT,BZ-1 and BZ-2 were polluted and should be treated in time by effective measures.
China ; Environmental Monitoring ; Eucommiaceae ; Metals, Heavy ; analysis ; Risk Assessment ; Soil ; chemistry ; Soil Pollutants ; analysis

In this study, we investigate the bioaccessibility of heavy metals (Cu, Pb, As, Cd and Hg) in wild Artemisia annua and use target hazard quotients (THQ) proposed by US Environmental Protection Agency to assess the health risk under the heavy metal exposure. The results showed that the bioaccessibility of Cu, Pb, As, Cd and Hg in A. annua are 0.77, 0.66, 0.46, 0.68 and 0, respectively, and that the value of THQ for adults and children were 0.030 and 0.025 calculated by risk assessment model. The results indicated that the heavy metals in A. annua were not able to be completely absorbed by human body and that their contents were in a safe range. In this study, by combining the bioavailability of heavy metal and health risk assessment, we assessed the security of heavy metals of wild A. annua, which will provide reference for the standard of heavy metals for medicinal materials.
Artemisia annua ; chemistry ; metabolism ; Consumer Product Safety ; Drug Contamination ; Humans ; Metals, Heavy ; analysis ; metabolism ; Risk Assessment ; Soil Pollutants ; analysis ; metabolism

Six heavy metals, including As, Cu, Hg, Cd, Pb and Cr in Panax notoginseng were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) combined with wet digestion method. The samples of P. notoginseng were collected in 12 different regions, including Yunnan and Guangxi Province. Green Standards of Foreign Trading Medicinal Plants & Preparations was used as the standard to evaluate the pollution status of As, Cu, Hg, Cd, Pb and Cr in P. notoginseng. The results showed that content of As and Cd exceeded the limit of the standard and the percentage was 32.4% and 29.7%, respectively, while Cu, Hg and Pb were all bellow the limit. The SPSS 16.0 software was used to analyze the data. The occurrence of contained heavy metals has been discussed.
China ; Drug Contamination ; Drugs, Chinese Herbal ; analysis ; Metals, Heavy ; analysis ; metabolism ; Panax notoginseng ; chemistry ; metabolism ; Soil Pollutants ; analysis ; metabolism

OBJECTIVEIn this study, five heavy metals contamination of soil and different parts of Panax notoginseng in the plantation area was investigated. Analysis of heavy metals correlation between the planting soil and P. notoginseng; and the absorption and accumulation characteristics and translocation of soil heavy metals by P. notoginseng plants was revealed.

METHODThrough field investigation and laboratory analytical methods, analysis of China's 30 different soil P. notoginseng origin and content of heavy metals in five different parts of the P. notoginseng plant content of heavy metals.

RESULTThe results revealed that the soil heavy metals should not be neglected in the plantation area Referring to the national soil quality standards (GB15608-1995), the excessive degree of soil heavy metals pollution showed Hg > As > Cd > Cr in the plantation area, and Pb content of soil was in the scope of the standard. Refer to 'Green Industry Standards for Import and Export of Medical Plants and Preparations', the excessive degree of heavy metals content of P. notoginseng plants showed As > Pb > Cr > Cd, and Hg content of plants was in the scope of the standard. Concentrations of five heavy metals of underground parts of P. notoginseng plants are higher than aboveground, and heavy metals elements are more concentrated in the root, followed by the rhizome of P. notoginseng plants. Heavy metal accumulation characteristics of the different parts of the P. notoginseng of the overall performance is the root > the rhizome > the root tuber > leaves > stems. From the point of view BCF value analysis of various parts of the P. notoginseng plants to absorb heavy metals in soil, BCF values of all samples were less than 1, description P. notoginseng not belong Hyperaccumulator. From the view of transportation and related analysis of the soil-P. notoginseng systems, the rhizome of P. notoginseng and the content of As and Cr in soil was significantly correlated, the root of P. notoginseng and the content of Cd in soil was significantly correlated, and no significant correlation between the other indicators. Through the analysis of transportation transfer coefficient showed: Pb, As and Cr are not easy to transport aboveground part from the underground, but Cd and Hg are relatively easy to transport stems from rhizome, the migration of five heavy metals in the aerial part is relatively strong, and heavy metal of stems is easily transported to the leaves.

CONCLUSIONP. notoginseng does not belong to the enrichment of heavy metals in crops, especially for Hg in soil with strong patience. In survey area, the content of heavy metals of P. notoginseng's planting soil is relatively high, and the heavy metals As, Pb, Cr, Cd of P. notoginseng also exist heavy metals exceeded problems. Due to the presence of heavy metals in crops internal absorption and translocation of special laws, accumulation of heavy metals varied significantly in different parts of P. notoginseng. The overall, the performance for the heavy metal content of the underground parts is more than aboveground, it explain heavy metals of P. notoginseng plants is still the main source of the soiL Therefore, the key to control of planting area soil environmental quality and reduce exogenous harmful substances secondary pollution of soil in the cultivation process are to study and solve the heavy metals pollution problem of P. notoginseng.

Adsorption ; China ; Laboratories ; Metals, Heavy ; analysis ; Panax notoginseng ; chemistry ; Soil ; chemistry ; Soil Pollutants ; analysis

OBJECTIVEThis paper aims to investigate the impact of anthracene addition on microbial community in agricultural soil irrigated with tap water or reclaimed wastewater.

METHODSThe changes of microbial community were characterized by terminal restriction fragment length polymorphism in combination with 16S rRNA gene clone library analysis.

RESULTSA significant change in microbial community composition was observed during the biodegradation of anthracene, with dominantly enriched members from the genus Methylophilus.

CONCLUSIONThis work might be useful for developing techniques for the isolation of novel putative PAH degrader.

Anthracenes ; analysis ; Bacteria ; classification ; genetics ; isolation & purification ; Biodegradation, Environmental ; DNA, Bacterial ; genetics ; isolation & purification ; Hazardous Waste ; Phylogeny ; Polymorphism, Restriction Fragment Length ; RNA, Ribosomal, 16S ; genetics ; Soil Microbiology ; Soil Pollutants ; analysis ; Waste Disposal, Fluid ; methods

OBJECTIVETo study the accumulation and translocation of cadmium in the soil and Artemisia annua, and observe its effects on growth of A. annua and artemisinin content.

METHODA. annua were cultivated in pots with Cd concentration at 0.5, 1.5, 4.5 mg x kg(-1) level, respectively.

RESULT AND CONCLUSIONThe growth of A. annua was inhibited at all the Cd levels characterized by the decreases of biomass and agronomic parameters; Most of Cd was accumulated in the roots of A. annua, and the ratios of Cd concentrations in roots and aerial part were 1.8:1 and 2.3:1 at 1.5, 4.5 mg x kg(-1) Cd level, respectively. Artemisinin content increased significant at 0.5 mg x kg(-1) Cd level, but there were no significant changes comparing with control group other Cd levels.

Artemisia annua ; chemistry ; drug effects ; growth & development ; metabolism ; Artemisinins ; analysis ; metabolism ; Cadmium ; analysis ; metabolism ; toxicity ; Plant Extracts ; analysis ; metabolism ; Soil Pollutants ; analysis ; metabolism ; toxicity