To study the effects of long-term mining activities on the agricultural soil quality of Mengnuo town in Yunnan province, China, the heavy metal and soil enzyme activities of soil samples from 47 ...sites were examined. The results showed that long-term mining processes led to point source heavy metal pollution and Pb, Cd, Zn and As were the primary metal pollutants. Polyphenoloxidase was found the most sensitive soil enzyme activity and significantly correlated with almost all the metals (P < 0.05). Amylase (for C cycling), acid phosphatase (for P cycling) and catalase (for redox reaction) activities showed significantly positive correlations (P < 0.05) with Pb, Cd, Zn and As contents. The correlations between soil enzymes activities and Cd, Pb and Zn contents were verified in microcosm experiments, it was found that catalase activity had significant correlations (P < 0.05) with these three metals in short-term experiments using different soils under different conditions. Based on both field investigation and microcosm simulation analysis, oxidoreductases activities (rather than a specific enzyme activity) were suggested to be used as “core enzyme”, which could simply and universally indicate the heavy metal pollution degrees of different environments. And hydrolases (for C, N, P and S recycling) could be used as a supplement to improve correlation accuracy for heavy metal indication in various polluted environments.
•Long-term Pb-Zn ore mining led to a point source heavy metal pollution.•Pb, Cd, Zn and As were the primary pollution metals in this region.•Polyphenoloxidase was found to be a good mining contamination bioindicator.•Oxidoreductase was proposed as enzyme indicators for soil heavy metal pollution.
Oxidoreductases could be used as a better and more sensitive bioindicator for soil heavy metal pollution than hydrolases.
•Generation potential, biomarkers and isotopes were investigated for coal macerals.•Liptinite and vitrinite in mudstones generate 70% and 30% of oils respectively.•Mudstone is a major source rock of ...oil in the Jurassic coal-bearing basins in China.
This paper examines the geochemical characteristics of pyrolysates from macerals such as the alginite, sporinite, cutinite, collotelinite and collodetrinite isolated from Jurassic coals and investigates their relative contributions to oil potential in respect to the Jurassic coal measures in the Turpan and other basins of northwest China. The alginite pyrolysate has the lightest carbon isotopic composition, followed by the sporinite and cutinite, while the collotelinite and collodetrinite pyrolysates show comparatively heavy carbon isotopic compositions. Pyrolysates from the alginite, sporinite and cutinite demonstrate much lower Pr/Ph ratios than those from the collotelinite and collodetrinite. Regarding the distributions of regular biomarkers such as steranes and hopanes, the alginite pyrolysate is comparatively rich in C27 steranes, followed by pyrolysates from the sporinite and cutinite, whereas pyrolysates from the collotelinite and collodetrinite contain little or undetectable C27 steranes. Furthermore, the pyrolysates from different kinds of macerals have remarkably different gammacerane concentrations. The gammacerane concentrations in pyrolysates from the alginite and cutinite are higher than that from the sporinite, though these macerals were separated from the same coal, whereas the collotelinite and collodetrinite pyrolysates have almost no gammacerane. The experimental results suggest that liptinite content in one given coal (e.g. alginite, sporinite and cutinite) controls the biomarker distributions in the coal-derived oils. Mass balance calculations of carbon isotopic compositions from the maceral pyrolysates show that the carbon isotopic composition of liquid hydrocarbons generated by organic matter in mudstone is very similar to that of most of the oils in the Jurassic coal-bearing basins of northwest China, while liquids from coal are much heavier than that of the oils. This indicates that the mudstone is likely to be the major source rocks of the oils, and coals likely to be the subordinate source rocks. Mass balance calculation based on the maceral contents and hydrocarbon-generative potential suggests that liptinites in mudstone in the Jurassic coal-measures of the Turpan Basin generate about 70% of oils, while the vitrinites produce about 30% of the oils. Therefore, the hydrogen-rich liptinites (alginite, sporinite and cutinite) are the main oil generating macerals, while vitrinites (collotelinite and collodetrinite) are secondary oil generating macerals in the Jurassic coal-bearing Turpan Basin and other Jurassic basins of northwest China.
Bacteriophage has attracted growing interest as a promising therapeutic agent for pathogenic bacteria, especially for antibiotic-resistant bacteria. However, the various abiotic conditions could ...impact the stability of phages and further threat host-virus interactions. Here, we investigated the stability and lytic activity of virulent polyvalent coliphage (named PE1) by double-layer plaque assay. PE1 can efficiently infect both the drug-sensitive Escherichia coli K12 and multidrug-resistant E. coli NDM-1 even after prolonged storage at 4 °C for up to two months. Results showed that PE1 exhibits an outstanding stability to infect E. coli strains under a wide range of thermal (4 °C-60 °C) and pH (4-11) conditions, which covers the thermal and pH variations of most wastewater treatment plants. Moreover, PE1 exhibited high resistibility to heavy metals exposure including Cu
, Cd
, Co
, and Cr
at the concentrations below 0.5 mM, and an excellent resistant ability to the variation of ionic strength, which still retained strong infectious ability even treated with saturated sodium chloride solution (350 g/L). This work shows that polyvalent phage PE1 has a strong adaptive capacity to various abiotic factors and should be a good candidate of being an antibacterial agent, especially for antibiotic-resistant bacteria control in sewage.
Background
BAT1706 is a proposed biosimilar of bevacizumab, a vascular endothelial growth factor A (VEGF-A)-targeting biologic used to treat several different cancers, including metastatic colorectal ...cancer. A comprehensive physicochemical and functional similarity assessment is a key component of demonstrating biosimilarity between a reference biologic and a proposed biosimilar. Here we report the physicochemical and functional similarity of BAT1706 and reference bevacizumab sourced from both the United States (US-bevacizumab) and the European Union (EU-bevacizumab).
Method
A large range of product attributes, including primary and higher order structure, post-translational modifications, purity, stability, and potency, were characterized for BAT1706 and EU/US-bevacizumab using sensitive state-of-the-art analytical techniques. Up to 18 lots of US- and 29 lots of EU-bevacizumab, and 10 unique drug substance lots of BAT1706, were assessed.
Result
BAT1706 was shown to have an identical amino acid sequence and an indistinguishable higher-order structure compared with EU/US-bevacizumab. BAT1706 and EU/US-bevacizumab also exhibited similar post-translational modifications, glycan profiles, and charge variants. Potency, assessed using a wide range of bioassays, was also shown to be comparable between BAT1706 and EU/US-bevacizumab, with statistical equivalence demonstrated for VEGF-A binding and neutralizing activity.
Conclusion
Overall, this extensive comparability exercise demonstrated BAT1706 to match EU/US-bevacizumab in terms of all physicochemical and functional attributes assessed.
To investigate the diversity of butane-oxidizing bacteria in soils contaminated by long-term light hydrocarbon microseepage and the influence of butane on the soil microbial community, a quantitative ...study and identification of butane-oxidizing bacteria (BOB) in soils at the Puguang gas field were performed by DNA-based stable isotope probing (DNA-SIP). For the first time, two phylotypes corresponding to the genera
and
were identified as being directly involved in butane oxidation, in addition to the well-known light hydrocarbon degrader
. Furthermore,
genes were strongly labeled by
C-butane, and their abundances in gas field soils increased by 43.14-, 17.39-, 21.74-, and 30.14-fold when incubated with butane for 6, 9, 12, and 14 days, respectively, indicating that these
harboring bacteria could use butane as the sole carbon and energy source and they play an important role in butane degradation. We also found that the addition of butane rapidly shaped the bacterial community and reduced the diversity of
genes in the gas field soils. These findings improve our understanding of BOB in the gas field environment and reveal the potential for their applications in petroleum exploration and bioremediation.
It is a challenge to determine the source and genetic relationship of condensate, waxy and heavy oils in one given complicated petroliferous area, where developed multiple sets of source rocks with ...different maturity and various chemical features.The central part of southern margin of Junggar Basin, NW China is such an example where there are condensates, light oils, normal density oils, heavy crude oils and natural gases. The formation mechanism of condensates has been seriously debated for long time;however, no study has integrated it with genetic types of waxy and heavy oils. Taking the central part of southern margin of Junggar Basin as a case, this study employs geological and geochemical methods to determine the formation mechanism of condensates,waxy and heavy oils in a complicated petroliferous area, and reveals the causes and geochemical processes of the co-occurrence of different types of crude oils in this region. Based on detailed geochemical analyses of more than 40 normal crude oils, light oils,condensates and heavy oils, it is found that the condensates are dominated by low carbon number n-alkanes and enriched in light naphthenics and aromatic hydrocarbons. Heptane values of these condensates range from 19% to 21%, isoheptane values from1.9 to 2.1, and toluene/n-heptane ratios from 1.5 to 2.0. The distribution of n-alkanes in the condensates presents a mirror image with high density waxy crude oils and heavy oils. Combined with the oil and gas-source correlations of the crude oils, condensates and natural gas, it is found that the condensates are product of evaporative fractionation and/or phase-controlled fractionation of reservoir crude oils which were derived from mature Cretaceous lacustrine source rocks in the relatively early stage. The waxy oils are the intermediate products of evaporative fractionation and/or phase-controlled fractionation of reservoir crude oils, while the heavy oils are in-situ residuals. Therefore, evaporative fractionation and/or phase-controlled fractionation would account for the formation of the condensate, light oil, waxy oil and heavy oil in the central part of southern margin of Junggar Basin, resulting in a great change of the content in terms of light alkanes, naphthenics and aromatics in condensates, followed by great uncertainties of toluene/n-heptane ratios due to migration and re-accumulation. The results suggest that the origin of the condensate cannot be simply concluded by its ratios of toluene/n-heptane and n-heptane/methylcyclohexane on the Thompson＇s cross-plot, it should be comprehensively determined by the aspects of geological background, thermal history of source rocks and petroleum generation,physical and chemical features of various crude oils and natural gas, vertical and lateral distribution of various crude oils in the study area.
Through detailed geochemical analysis of over 40 crude oil, condensate oil and heavy oil samples in the southern margin of Junggar Basin, and based on the hydrocarbon generation condition of five ...sets of source rocks, with the combination between compositions of carbon isotopes of whole oil, light hydrocarbon, n-alkanes isoprenoids and biomarker composition characteristics, a detailed discussion on the source of the condensate oil in anticlines in the central part of the southern margin was carried out. Condensate oils from the central part of the southern margin have abundant isoprenoids, Pr/Ph<1.0. Carbon isotopes of whole oil are low with δ13C value between −27‰ and −28‰. The δ13C value of alkanes with carbon number smaller than 9 ranges from −26‰ to −24‰, carbon isotopes of C9+ n-alkanes decrease remarkably with increasing carbon number, and the δ13C value of C19+ n-alkanes is lower than −30‰. The δ13C value of pristane and phytane is lower than −29‰. The biomarker components contain abundant C27 steranes and C30 methyl steranes, “V” shape distribution of C27, C28 and C29 20R sterane, abundant tricyclic terpanes with dominance of C21, and relatively high content of gammacerane with two isomers. The 20S/(20S+20R) ratio of C29 steranes is between 0.40 and 0.50, and the maturity calculated by the methylphenanthrene index and distribution fraction (Rc) ranges from 0.70% to 1.1%. These geochemical characteristics of the condensate oils are very similar to those mature crude oils from the typical Cretaceous lacustrine source rocks in the central part of southern margin, but are greatly different from those of typical Jurassic crude oils, implying that these condensate oils are derived from mature Cretaceous lacustrine source rocks instead of highly mature Jurassic coal-measures source rocks.
The semi-closed pyrolysis simulation system under constant pressure was conducted to explore the characteristics and mecha- nisms of hydrocarbon generation from Xiamaling Formation shale in ...Xiahuayuan, North China. The experiment results indi- cate the oil generated by the Xiamaling Formation shale in oil window should be classified as ＂aromatic-intermediate＂ type, whereas the decreasing of dry coefficient can be ascribed to the cracking of residual bitumen in source rock in the stage of high to post maturity. The amount of hydrocarbon gas generated from residual bitumen can be up to 1-2 m3 per ton rock in high to post mature stage by calculating hydrogen contents in the kerogen, the expelled hydrocarbon, and the residual hydrocarbon. This reveals the importance of residual bitumen as a gas source during high to post mature stage of the kerogen evolution, and also as the broad exploration prospect of these gases. This research highlights the attention should be paid to oil/gas reservoirs sourced from residual bitumen of organic-rich source rock in high mature stage, even the primary oil/gas reservoirs considered as the main exploration targets in middle-upper Proterozoic sediments of North China.
Light hydrocarbons accumulated in subsurface soil by long-term microseepage could favor the anomalous growth of indigenous hydrocarbon-oxidizing microorganisms, which could be crucial indicators of ...underlying petroleum reservoirs. Here, Illumina MiSeq sequencing of the 16S rRNA gene was conducted to determine the bacterial community structures in soil samples collected from three typical oil and gas fields at different locations in China. Incubation with n-butane at the laboratory scale was performed to confirm the presence of "universal microbes" in light-hydrocarbon microseepage ecosystems. The results indicated significantly higher bacterial diversity in next-to-well samples compared with background samples at two of the three sites, which were notably different to oil-contaminated environments. Variation partitioning analysis showed that the bacterial community structures above the oil and gas fields at the scale of the present study were shaped mainly by environmental parameters, and geographic location was able to explain only 7.05% of the variation independently. The linear discriminant analysis effect size method revealed that the oil and gas fields significantly favored the growth of Mycobacterium, Flavobacterium, and Pseudomonas, as well as other related bacteria. The relative abundance of Mycobacterium and Pseudomonas increased notably after n-butane cultivation, which highlighted their potential as biomarkers of underlying oil deposits. This work contributes to a broader perspective on the bacterial community structures shaped by long-term light-hydrocarbon microseepage and proposes relatively universal indicators, providing an additional resource for the improvement of microbial prospecting of oil and gas.
To research the characteristics and petroleum geological significance of micro pores, this paper uses Second Electron Microscope (SEM) and secondary SEM imaging capability in Field Emission SEM ...(FE-SEM) to characterize shale from the first member of the Cretaceous Qingshankou Formation, Songliao Basin. There are five major pore types in the shale, including matrix intercrystal, organic, dissolution, interparticle, and intracrystalline pores. In addition, there are a mass of micro-fractures of micron-submicron (nano-) scale, including dissolution, filled and interlayer fractures. The existence of complex fracture-pore systems provides an effective pathway for primary migration and it also provides ample storage space for the residual petroleum in shale, which is important for the primary migration and storage for shale oil and gas resources.
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