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Currently, a big problem is increasing the production of residual oil, for which so-called tertiary recovery methods are used. One common tertiary recovery method is the use of surfactants. The use of biological surfactants instead of synthetic ones can solve the problem of increasing oil production and reducing the toxic impact on the environment. To obtain biosurfactants, two strains of Bacillus mojavensis and Bacillus amyloliquefaciens were used. These strains are characterized by the ability to produce biosurf...

Soil contamination by polycyclic aromatic hydrocarbons (PAHs) is a widespread concern due to the high potential for human exposure through inhalation, ingestion, and dermal contact. In this study, we compared the efficiency of three different methods for PAHs extraction from model samples, including ultrasonic (US), mechanical shaking and purification with commercial QuEChERS kit (Shq), and ultrasonic extraction coupled with QuEChERS (USq) by gas chromatography coupled to a triple quadrupole tandem mass-spectromet...

Surfactants play an important role in enhanced oil recovery by creating an oil-water emulsion that will be easier to recover from the reservoir. It is known that sulfatereducing bacteria (SRB) can use surfactants as a carbon source, which can increase the biological accumulation of sulfides and, accordingly, the corrosion of oil production equipment. Thus, all new surfactants used in oil production need to be pre-tested for SRB. The aim of this study was to evaluate the effect of four new groups of synthesized sur...

Surfactants as detergents and emulsifying agents are used in various fields of industry and agriculture. These amphiphilic compounds contain hydrophobic and hydrophilic fragments and are usually produced by large-scale chemical synthesis processes. However, recently there is a request to develop biotechnological methods to obtain surfactants, since biosurfactants have many advantages above their chemical analogues - higher tolerance to extreme temperatures, pH and salinity, higher stability and lower or zero negat...

Biosurfactants produced by soil microorganisms are now widely used in various industries and are able to compete with synthetic detergents. However, in contrast with chemical surfactants, biological ones have disadvantage: it is difficult to obtain the product of high purity since the microbes usually produce a complex mixture of compounds, besides the cultural medium itself contains a lot of various components. Thus, the conventional scheme of lipopeptide isolation involves acid precipitation, extraction with the...

Public gardens and park zones are an important and widely visited component of urban spaces worldwide, however they can be polluted and even dangerous for humans and animals visiting them. The simplest way to screen the level of pollution of those green zones is to assess their ecological toxicity. In the present study, to assess the ecotoxicity of soil and ground samples obtained in 15 parks and public gardens in the city of Kazan (Russia) with 1 Mio citizens were investigated. Two elutriate assays with Ceriodaph...

Surfactants produced by microorganisms, known as biosurfactants, have recently found wide application in the industry, from cosmetology to oil processing. Biosurfactants are more tolerant to extreme environmental conditions and less hazardous for the environment as compared with their chemical analogues. Despite on the fact that many biosurfactant producers have been recently isolated and described, the challenge to explore new producers still remains very urgent. In the present study, the isolates obtained from r...

Biochar attracts high scientific and practical interest because of several specific properties such as high sorption potential, fertilizing properties and ability to sequester carbon. In the present study, fertilizing properties of biochar made of chicken manure using different peak temperatures (2h at 300-700 ?C) in the rotating experimental 200L biomass pyrolysis plant were investigated. The following parameters were analyzed: content of biogenic elements (C, N, P, K), porosity and micromorphology, toxicity for ...