In China, the crude oil supply is highly dependent on overseas countries, and thus strengthening crude oil self-sufficiency has become an important issue of the national energy security. Tertiary oil recovery, especially polymer flooding, has been widely applied in large oil fields in China, which can increase the recovery rate by 15%-20% compared with water flooding. However, the widely used oil flooding polymers show poor thermal stability and salinity tolerance, complicated synthesis ways of monomers, and environmental unfriendliness. Moreover, the polymer flooding induces problems including pore plugging, heterogeneity intensification, high dispersion of remaining oil resources, pressure rise in injection wells, and low efficiency circulation of injection medium, which restrict the subsequent recovery of old oil fields. Here, we systematically review the developing and current situations of polymer flooding, introduce the innovative biomanufacturing of oil flooding polymers and their monomers or precursors as well as low-cost bio-based chemical raw materials for multiple compound flooding. The comprehensive study of the relationships between microbial fermentation metabolites and polymer flooding will reveal the green and low-carbon paths for polymer flooding. Such study will enable the application of enzymes produced by microorganisms in polymer production and polymer plugging removal after polymer flooding as well as the application of microbial metabolites such as biosurfactants, organic acids, alcohols, biogas, and amino acids in enhancing oil recovery. This review suggests that incorporating biomanufacturing into polymer flooding will ensure the high productivity and stability for crude oil production in China.
Polymers/metabolism* ; China ; Petroleum ; Oil and Gas Fields

Petroleum hydrocarbon pollution has become one of the global environmental problems, posing a serious threat to the environment and human health. Microbial remediation plays an important role in the remediation of petroleum hydrocarbon-contaminated environment. Nevertheless, the stress factors present in the environment polluted by petroleum hydrocarbons limit the effectiveness of microbial remediation. This paper reviews the common stress factors in petroleum hydrocarbon-polluted environment and the response mechanisms of microorganisms to these factors. Furthermore, we introduce the methods to improve microbial tolerance, such as irrational modification, rational modification based on systems biology tools or tolerance mechanisms, and the construction of microbial consortia. The application of these methods is expected to improve the viability and remediation efficiency of microorganisms in petroleum hydrocarbon-contaminated environment and provide new perspectives and technical support for environmental remediation.
Biodegradation, Environmental ; Petroleum/metabolism* ; Hydrocarbons/isolation & purification* ; Bacteria/genetics* ; Environmental Pollutants/isolation & purification* ; Petroleum Pollution

Plastics are widely used in human daily life, which bring great convenience. Nevertheless, the disposal of a large amount of plastic wastes also brings great pressure to the environment. Polyethylene terephthalate (PET) is a polymer thermoplastic material produced from petroleum. It has become one of the most commonly used plastics in the world due to its durability, high transparency, light weight and other characteristics. PET can exist in nature for a long time due to its complex structure and the difficulty in degradation, which causes serious pollution to the global ecological environment, and threatens human health. The degradation of PET wastes has since become one of the global challenges. Compared with physical and chemical methods, biodegradation is the greenest way for treating PET wastes. This review summarizes the recent advances on PET biodegradation including microbial and enzymatic degradation of PET, biodegradation pathway, biodegradation mechanisms, and molecular modification of PET-degrading enzymes. In addition, the prospect for achieveing efficient degradation of PET, searching and improving microorganisms or enzymes that can degrade PET of high crystallinity are presented, with the aimto facilitate the development, application and molecular modification of PET biodegradation microorganisms or enzymes.
Humans ; Polyethylene Terephthalates/metabolism* ; Polymers ; Biodegradation, Environmental ; Petroleum

In recent years, the petroleum-based plastic pollution problem has been causing global attention. The idea of "degradation and up-cycling of plastics" was proposed for solving the environmental pollution caused by non-degradable plastics. Following this idea, plastics would be firstly degraded and then reconstructed. Polyhydroxyalkanoates (PHA) can be produced from the degraded plastic monomers as a choice to recycle among various plastics. PHA, a family of biopolyesters synthesized by many microbes, have attracted great interest in industrial, agricultural and medical sectors due to its biodegradability, biocompatibility, thermoplasticity and carbon neutrality. Moreover, the regulations on PHA monomer compositions, processing technology, and modification methods may further improve the material properties, making PHA a promising alternative to traditional plastics. Furthermore, the application of the "next-generation industrial biotechnology (NGIB)" utilizing extremophiles for PHA production is expected to enhance the PHA market competitiveness, promoting this environmentally friendly bio-based material to partially replace petroleum-based products, and achieve sustainable development with carbon-neutrality. This review summarizes the basic material properties, plastic upcycling via PHA biosynthesis, processing and modification methods of PHA, and biosynthesis of novel PHA.
Polyhydroxyalkanoates ; Plastics ; Biotechnology ; Petroleum ; Carbon

Objective: To provide scientific evidence for early lung cancer screening, to analyze the incidence of pulmonary nodules among petroleum company staffs in Sichuan-Chongqing Area. Methods: In January 2021 , 6002 petroleum company staffs in Sichuan-Chongqing Area which scanned by low-dose spiral computed tomography (LDCT) of chest in medical examination center in 2020 were retrospectively collected as objects. Their imaging and clinical data were collected. χ(2) test was used to analyze the differences in the detection rates of lung nodules and suspected lung cancer nodules among workers in petroleum company staffs of different genders, ages and types of work. Results: Among the 6002 objects, 3853 (64.2%) were male and 2149 (35.8%) were female, with an average age of (47.25±12.13) years old. A total of 431 cases (7.2%) of pulmonary nodules and 57 cases (0.9%) of suspected lung cancer nodules were detected. 45 cases were followed up with surgical treatment, and 41 cases (91.1%) of lung cancer were diagnosed by postoperative pathology. There were significant differences in the detection rates of pulmonary nodules and suspected lung cancer nodules between different age groups (χ(2)=51.23, 18.81 , P<0.001). The detection rates of pulmonary nodules in the age groups 51-60 years old and ≥61 years old were higher than those in the age groups≤40 years old and 41-50 years old (P<0.05). The detection rate of suspected lung cancer nodules in the age group≥ 61 years old was higher than those in the age groups≤40 years old, 41-50 years old and 51-60 years old (P< 0.05) . And the detection rate of suspected lung cancer pulmonary nodules in oil workers was higher than that of ordinary workers (P<0.05) . Among female objects, the detection rate of pulmonary nodules in oil workers was higher than that in ordinary workers (χ(2)=8.09, P=0.004) . The detection rate of pulmonary nodules in oil workers aged ≥61 years old was higher than ordinary workers (χ(2)=37.94, P<0.001) . Among male objects, the detection rate of suspected lung cancer pulmonary nodules in oil workers was higher than that in ordinary workers (χ(2)=8.42, P=0.004) . The detection rates of suspected lung cancer pulmonary nodules in oil workers aged 51-60 years old and ≥61 years old groups were higher than those of ordinary workers (χ(2)=4.70, 8.74; P=0.030, 0.003) . Conclusion: LDCT is suitable for early lung cancer screening for petroleum company staffs. During the clinical screening process, LDCT should be used as a routine physical examination item for petroleum workers older than 51 years old.
Adult ; Early Detection of Cancer/methods* ; Female ; Humans ; Lung Neoplasms/diagnosis* ; Male ; Mass Screening/methods* ; Middle Aged ; Multiple Pulmonary Nodules/diagnostic imaging* ; Petroleum ; Retrospective Studies ; Tomography, Spiral Computed

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

OBJECTIVE: To investigate the role of petroleum ether extract of Rhizoma Amorphophalli (SLG) in inhibiting proliferation and promoting apoptosis and differentiation of leukemia K562 cells. METHODS: K562 cells were processed by SLG and PD98059 which was the ERK signaling pathway blocker. Then cell vitality was tested by MTT. Cell apoptosis rate and positive percentage of antigen expression related with differentiation were detected by flow cytometry. The protein expression levels of ERK1/2 and pERK1/2 were detected by Western blot. RESULTS: The proliferation activity of K562 was reduced by 50, 100, 200 mg/L SLG in a concentration dependent manner (r=0.9997). The apoptosis rate and positive expression rate of CD11b, CD14 and CD42b which were related with differentiation were raised by SLG, as well as the expression of pERK1/2, while PD98059 could reverse the promoting effect of SLG on apoptosis and differentiation partially. CONCLUSION SLG can inhibit the proliferation and promote apoptosis and differentiation of K562 cells through ERK signaling pathway.
Alkanes ; Apoptosis ; Cell Proliferation ; Humans ; K562 Cells ; Petroleum ; Plant Extracts/pharmacology*

Polyhydroxyalkanoates (PHAs) are polymers obtained by esterification of hydroxy fatty acid monomers. Due to similar mechanical characteristics of traditional petroleum-based plastics, 100% biodegradability and biocompatibility, PHAs are considered to be one of the most potential green materials. However, the application and promotion of PHAs as a green and environmentally friendly material are difficult because of the high production costs. This article focuses on the current methods to reduce production cost of PHAs effectively, such as cell morphology regulation, metabolic pathway construction, economic carbon source utilization and open fermentation technology development. Despite most research results are still limited in laboratory, the research methods and directions provide theoretical guidance for the industrial production of economic PHAs.
Fermentation ; Industry ; Petroleum ; Plastics ; Polyhydroxyalkanoates

Along with the increasingly serious environmental pollution, dealing with the "white pollution" issue, which is caused by the worldwide use of not readily-degradable or non-degradable synthetic plastics, has become a great challenge. It is an environmentally friendly strategy to degrade synthetic plastics using microorganisms that exist in nature or evolved under selection pressure. Based on the NSFC-EU International Cooperation and Exchanges Project "Bio Innovation of a Circular Economy for Plastics", this review summarized the screening of bacteria, fungi and microbial consortia capable of degrading synthetic plastics such as polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), polyurethane (PUR), and polyethylene terephthalate (PET). We also analyzed the role of various microorganisms played in the degradation of petroleum-based plastics. Moreover, we discussed the pros and cons of using microorganisms and enzymes for degradation of synthetic plastics.
Biodegradation, Environmental ; Microbial Consortia ; Petroleum ; Plastics ; Polyurethanes

Bioremediation is considered as a cost-effective, efficient and free-of-secondary-pollution technology for petroleum pollution remediation. Due to the limitation of soil environmental conditions and the nature of petroleum pollutants, the insufficient number and the low growth rate of indigenous petroleum-degrading microorganisms in soil lead to long remediation cycle and poor remediation efficiency. Bioaugmentation can effectively improve the biodegradation efficiency. By supplying functional microbes or microbial consortia, immobilized microbes, surfactants and growth substrates, the remediation effect of indigenous microorganisms on petroleum pollutants in soil can be boosted. This article summarizes the reported petroleum-degrading microbes and the main factors influencing microbial remediation of petroleum contaminated soil. Moreover, this article discusses a variety of effective strategies to enhance the bioremediation efficiency, as well as future directions of bioaugmentation strategies.
Biodegradation, Environmental ; Petroleum ; Soil ; Soil Microbiology ; Soil Pollutants