Since the beginning of their production and use, fossil fuels have affected ecosystems, causing significant damage to their biodiversity. Bacterial bioremediation can provide solutions to this environmental problem. In this study, the new species Isoptericola peretonis sp. nov. 4D.3T has been characterized and compared to other closely related species in terms of hydrocarbon degradation and biosurfactant production by in vitro and in silico analyses. Biosurfactants play an important role in microbial hydrocarbon degradation by emulsifying hydrocarbons and making them accessible to the microbial degradation machinery. The tests performed showed positive results to a greater or lesser degree for all strains. In the synthesis of biosurfactants, all the strains tested showed biosurfactant activity in three complementary assays (CTAB, hemolysis and E24%) and rhamnolipid synthesis genes have been predicted in silico in the majority of Isoptericola strains. Regarding hydrocarbon degradation, all the Isoptericola strains analyzed presented putative genes responsible for the aerobic and anaerobic degradation of aromatic and alkane hydrocarbons. Overall, our results highlight the metabolic diversity and the biochemical robustness of the Isoptericola genus which is proposed to be of interest in the field of hydrocarbon bioremediation.

Biosurfactants are one of the recently investigated biomolecules that have enormous applications in many fields including agriculture. As there is a need to develop less toxic, and environmentally friendly surfactants, therefore, amino acid-based biosurfactants that are produced from renewable raw materials are of great demand nowadays and can be used as an alternative to conventional chemical surfactants. The negative effects of chemical surfactants present in agrochemicals and modern detergents can damage human health and the environment, thus there is a crucial requirement to explore innovative, well planned, as well as cost-effective natural products for the welfare of humanity. Biodegradable surfactants created through green chemistry, specifically amino acid-based surfactants, are a favourable alternative to avoid these risks. Since amino acids (AAs) are inexhaustible compounds, therefore biosurfactants based on AAs have abundant potential as eco-friendly and environmentally friendly substances. Their higher biodegradation ability, low or even no toxicity, temperature stability, and tolerance to pH fluctuations make these biosurfactants preferable over chemical surfactants. In modern agriculture, most chemical pesticides and fertilizers used are frequently associated with numerous environmental issues. Hence, the development of green molecules as biosurfactants has a promising role in this regard to ensure agricultural sustainability. Biosurfactants can be harnessed for plant pathogen management, plant growth elevation, improving the quality of agricultural soil by soil remediation, degradation of complex hydrocarbons, increasing bioavailability of nutrients for advantageous plant-microbe interactions, and improving plant immunity, hence, they can supersede the grim synthetic surfactants which are presently being used.

Fusarium is genetically diverse and widely distributed geographically. It is one of the genera with more endophytes (which cause no damage to the host plants). This review highlights the capability of Fusarium species to degrade environmental pollutants and describes the biodegradation pathways of some of the emerging environmental contaminants. Some Fusarium species use metabolic strategies enabling them to efficiently mineralize high concentrations of toxic environmental pollutants. These fungi can degrade hydrocarbons, pesticides, herbicides, dyes, pharmaceutical compounds, explosives, plastics, and plastic additives, among other pollutants, and possess high metal biosorption capabilities. According to data from consulted reports, Fusarium strains showed a percentage of biodegradation of a variety of contaminants ranging between 30 % and 100 % for different tested concentrations (from 1 mg to 10 g/L) in a time range between 10 hand 90 d. Enzymes such as esterase, cutinase, laccase, lignin peroxidase, manganese peroxidase, dehydrogenase, lipase, dioxygenase, and phosphoesterase were detected during the pollutant biodegradation process. Fusarium oxysporum, Fusarium solani, and Fusarium culmorum are the most studied species of this genus. Owing to their metabolic versatility, these fungal species and their enzymes represent promising tools for bioremediation applications to mitigate the adverse effects of environmental pollution.

PurposeA of in-service PE gas pipeline in Guocun, Beijing, was found to appear gas leaking at the electrofusion (EF) joint. This study is dedicated to reveal the material cause of EF joint failure to help with a more accurate prediction of service life of PE gas pipe and further normalize the construction of PE gas pipeline.Design/methodology/approachDefect detection was carried out on the leaking EF joint using ultrasonic phased array. The mechanical degradation and structural aging behavior was studied by tension test, FTIR technology, TG test and DSC test. The organic components in the soil surrounding the PE gas pipe failure area were qualitatively identified.FindingsThe results showed that the organic surfactants in the soil environment could accelerate the aging behavior of PE material, leading to a deterioration of mechanical properties and a serious reduction in the ability of the PE pipe and EF joint, especially at the welding defect, to resist external force.Originality/valueA novel study was conducted to investigate the failure cause of the EF joint of in-service PE gas pipe, incorporating the analysis of environmental factors and structural deterioration.

Nanobubbles (NBs), given their unique properties, could theoretically be paired with rhamnolipids (RL) to tackle polycyclic aromatic hydrocarbon contamination in groundwater. This approach may overcome the limitations of traditional surfactants, such as high toxicity and low efficiency. In this study, the remediation efficiency of RL, with or without NBs, was assessed through soil column experiments (soil contaminated with phenanthrene). Through the analysis of the two-site non-equilibrium diffusion model, there was a synergistic effect between NBs and RL. The introduction of NBs led to a reduction of up to 24.3 % in the total removal time of phenanthrene. The direct reason for this was that with NBs, the retardation factor of RL was reduced by 1.9 % to 15.4 %, which accelerated the solute replacement of RL. The reasons for this synergy were multifaceted. Detailed analysis reveals that NBs improve RL's colloidal stability, increase its absolute zeta potential, and reduce its soil adsorption capacity by 13.3 %-19.9 %. Furthermore, NBs and their interaction with RL substantially diminish the surface tension, contact angle, and dynamic viscosity of the leaching solution. These changes in surface thermodynamic and rheological properties significantly enhance the migration efficiency of the eluent. The research outcomes facilitate a thorough comprehension of NBs' attributes and their relevant applications, and propose an eco-friendly method to improve the efficiency of surfactant remediation.

Surfactants are used in agriculture as soil conditioners and components of fungicides, pesticides, and fertilizers. These materials are considered contaminants found in the soil. They can be absorbed by plants and animals and can impact human health when consumed. The objective of this study was to evaluate the phytotoxicity of four cationic surfactants: hexadecyl trimethyl ammonium bromide (HDTMA), octadecyl trimethyl ammonium chloride amine and amine in a hydroponic culture system of lettuce in doses of 0 to 10 mg/L. The variables evaluated were water consumption, dry biomass, leaf area, electrical conductivity (EC), and content of NO3-, K+, and Ca2+in the nutrient solution. After 40 days of exposure to DDA, this did not influence the dry biomass of the plant; however, the application of 1 mg/L of HDTMA decreased the biomass by 27 %, 46 % with 4 mg/L of OTAC, and 60 % with 4 mg/L of HDA. The decrease in water consumption by surfactants was 27 % with 1 mg/L of HDTMA, 20 % with OTAC, and 34 % with HDA from 2 mg/L, and the application of DDA did not show a reducing effect. In most of the variables, the DDA surfactant did not affect the response; in addition, the HDA surfactant was the second to cause the least damage to the crop because it does not have a toxic companion ion such as Cl and Br.