Characteristics of lipid fractions of larvae of the black soldier fly Hermetia illucens.

The lipid fraction of larvae of the black soldier fly Hermetia illucens was shown to contain lauric acid (38.43 wt %) and its esters, azelaic and sebacic acids, and azelaic acid dibutyl ester. The dominant compound in the group of identified glycerides was lauric acid monoglyceride (0.70 wt %). Glycerides were also represented by triglycerides and diglycerides of lauric acid. Sterols were represented primarily by phytosterols (over 75%), the major of which was alpha-sitosterol (45%). The identified lipid complex composition is apparently determined by the biological characteristics of the fly Hermetia illucens and ensures antibacterial defence of larvae and stability of lipids at changing ambient temperature.

[Bioremediation of oil-polluted soils: using the [13C]/[12C] ratio to characterize microbial products of oil hydrocarbon biodegradation].

We compared data on the extent of bioremediation in soils polluted with oil. The data were obtained using conventional methods of hydrocarbon determination: extraction gas chromatography-mass spectrometry, extraction IR spectroscopy, and extraction gravimetry. Due to differences in the relative abundances of the stable carbon isotopes (13C/12C) in oil and in soil organic matter, these ratios could be used as natural isotopic labels of either substance. Extraction gravimetry in combination with characteristics of the carbon isotope composition of organic products in the soil before and after bioremediation was shown to be the most informative approach to an evaluation of soil bioremediation. At present, it is the only method enabling quantification of the total petroleum hydrocarbons in oil-polluted soil, as well as of the amounts of hydrocarbons remaining after bioremediation and those microbially transformed into organic products and biomass.

[Anaerobic solid-phase fermentation of plant substrates by Bacillus subtilis].

Solid-phase growth of Bacillus subtilis 8130 on cellulose-rich plant substrates (presscakes or pulp) under hypoxic conditions was accompanied by cellulose depolymerization, protein hydrolysis, and degradation of other plant components, including some processes of mixed-type carbohydrate fermentation. The bacterial fermentation yielded propionic, butyric, and hexanoic acids and butyric acid derivatives. The bacterial metabolism and fermentation degree can be characterized by the proportions of fatty acids in the reaction mixture. The product of sea buckthorn cake fermentation has a good sorption quality.

[Dioxins in the environment and in the blood and breast milk of residents of the town of Chapayevsk]. / Dioksiny v okruzhaiushchei srede, v krovi i grudnom moloke zhitelei goroda Chapaevska.

Chapayevsk has a 30-year history of producing organochlorines, leading to environmental dioxin pollution. As much as 3 kg of these substances are annually formed at the plant. The concentrations of dioxins in the ambient air were found to be 0.001 to 1.13 pg/m3, in 1-TEF dioxin equivalent or 0.00001-1.76 pg/m3, as calculated by using WHO-TEF for dioxin-like compounds, those in the urban drinking water were 0.1 to 20.83 pg/liter, in the soil near the plant, 141 ng TEQ/kg, by decreasing to 37 ng/kg in the downtown (2-7 km from the plant) and 4 ng/kg at a distance of 7-10 km from the plant, their levels in the vegetables and fruits were 0.002 to 10.6 pg/kg. The direct indicator of dioxin exposure is its detection in human breast milk and blood. Examination of the content of dioxins in the breast milk of Chapayevsk women versus those living in other towns and cities of Russia has shown considerably higher levels of dioxins, such as 2,3,7,8-TCDD, 1,2,3,7,8-PCDD, 1,2,3,4,7,8-GCDD, and octa-dioxins. The mean content of dioxins in the breast milk (7 pooled samples from 40 individual trials) was 43.3 pgTEQ/fat. It is significantly higher than that detected in the populations of other Russian territories and other countries. The mean blood concentrations of dioxins in peoples living near the plant was 75.2 pgTEQ/fat, those were lower (24.5 pgTEQ/fat) in those living at 5-7 km of the plant.