Chemistry. Ecology. Biotechnology

Results of the study of the OA mineralization by catalytic ozonation

It can be seen (from the table) that the most effective catalyst was obtained by the sewage sludge carbonization. In the presence of the catalyst in the reaction medium significant increase of ozone absorption rate and intensification of the OA mineralization were observed.

УДК 661.772

M.V. Postnikova, I.A. Isakova

PRODUCTION OF CELLULOSE NANOPARTICLES

FROM RAW WOOD

Perm National Research Polytechnic University

Cellulose is a nanostructured polymer that contains two domains: crystalline domain and amorphous domain. Amorphous domains of the cellulose structure are most accessible for acid reactions, oxidants, enzymes and other reagents. Due to the nanostructure and the ability of the non-crystalline regions to easily break down due to certain chemical reagents, it is possible to obtain free cellulose nanoparticles and use them as nanocarriers. Currently the issues of obtaining different types of cellulose nanoparticles, their modification and usage are relevant.

Cellulose nanoparticles may be nanocrystalline (filamentous defectfree single crystals) and cellulose nanofibers that are also called microfibrillated cellulose (filamentous particles with alternating crystalline and disordered areas). Cellulose nanofibers (nanocellulose) are the type of powdered cellulose (PC) or microcrystalline cellulose (MCC). Nanocellu-

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lose is a material composed of nanosized cellulose fibrils with a high aspect ratio (length to width ratio). Usually this fiber is 5–20 nanometers in width and varies from 10 nanometers to several microns in length. It has attracted considerable attention due to its unique optical properties, high strength, large surface area and sustainable raw material origin. Its fascinating properties allow creating ultra-light and ultra-strong materials on its basis.

In industry nanocrystalline cellulose is extracted from cotton cellulose by hydrolytic degradation. Also there are known processes of extracting nanoparticles from wood bleached pulp. These methods of obtaining MCC are based on the usage of expensive raw materials. Thus, currently one of the main objectives of research is to find ways to get cellulose nanoparticles from cheap raw wood.

The purpose of this research work is to study 1) the possibility to produce cellulose nanoparticles from wood raw material using enzymatic hydrolysis and 2) the properties of the obtained cellulose nanoparticles.

To get cellulose nanoparticles we used sawdust softwood and hardwood as raw materials. As a result, we got samples of 49.9-53.4% cellulose by oxidative delignification with hydrogen peroxide and acetic acid solution. Then the samples were subjected to enzymatic treatment using cellulolytic microorganisms. For enzymatic hydrolysis we have identified such microorganisms as bacteria of Clostridium and Bacclillus genera in anaerobic conditions, and myxobacteria of Sorangium and Cutophaga genera, that decompose cellulose aerobically. These strains of microorganisms are producers of cellulases – enzyme complexes that catalyze the hydrolysis of cellulose to glucose. To obtain cellulose we use part-enzymatic hydrolysis to the estimated DP of 180-250.

In the research, instead of acid hydrolysis we used the enzymatic hydrolysis conducted within three days. We determined the quantity of reducing sugars (PB), and after the mass of nanocellulose was separated from the hydrolysate, it was washed to neutral pH and the quantity of nanocellulose and degree of polymerization was determined. Nanocellulose was obtained with a degree of polymerization of 200-220 and purity of 88.2-90.0% from weight of absolutely dry cellulose. The properties of the received nanocellulose and composite materials on its basis were studied using physical and chemical methods of analysis.

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УДК 661

E.A. Sushkova, M.V. Postnikova

PRODUCTION OF BACTERIAL CELLULOSE

Perm National Research Polytechnic University

Cellulose is the earth’s major biopolymer and has an exclusive global economic importance. In nature it exists in two forms: pure cellulose and cellulose as a part of the vegetable raw material matrix.

Bacterial cellulose is the pure cellulose. Bacterial cellulose is an exopolysaccharide produced by various species of bacteria, such kinds of gen-

era as Gluconacetobacter, Acetobacter, Agrobacterium, Aerobacter, Achromobacter, Rhizobium, Sarcina, and symbiotic culture Medusomyces gisevii.

The molecular formulae of bacterial cellulose and plant cellulose are the same (C6H10O5), but their physical and chemical features are different. Bacterial cellulose is preferred over the plant cellulose as it can be obtained in higher purity and exhibits a higher degree of polymerization and crystallinity index.

It also has a higher tensile strength and water holding capacity than plant cellulose. Fibrils of bacterial cellulose are about 100 times thinner than those of plant cellulose, making it a highly porous material.

Bacterial cellulose can be used as a diet food and also can be used in production to get new materials for high performance speaker diaphragms, medical pads and artificial skin.

Bacterial cellulose is widely used in medicine. Gel bacterial cellulose film can be used in microsurgery in vascular prosthetics. Moreover, medications based on it can restore articular cartilage. Nanocomposite bacterial cellulose may be used in bone tissue engineering; based on bacterial cellulose matrix fabric has anti-inflammatory and healing properties.

Currently there is no production of bacterial cellulose in Russia due to the fact that the effective, and also cost-effective, biotechnologies are not developed. Therefore, the purpose of the work is to develop technologies of bacterial cellulose production.

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The bacterial cellulose producer was made of Kombucha, also purification technique and preparation of samples for the further material usage in various spheres were studied. In the end we got bacterial cellulose film and flaky material from cultivations of gel producing bacteria. The obtained bacterial cellulose film had a high porosity and sorption capacity.

The results show that optimization and making the production on an industrial scale is possible without product quality loss.

УДК 66-971

A.A. Glushkova1, Yu.G. Maksimova2

ISOLATION OF BACTERIAL STRAINS

DEGRADING ANILINE

1 Perm National Research Polytechnic University

2 Institute of Ecology and Genetics of Microorganisms UB RAS, Perm

Aniline is a representative of an aromatic amines class, the toxic substance which can penetrate the body by the contact with skin and mucous membranes and as a vapor by inhalation. Aniline and its derivatives permeate the environment as a part of sewage petroleum, paper, coal and chemical industry. Aniline dumps into the environment are increasing and are an important problem now. Cleaning of soil and water contaminated with aniline can be performed with biotechnologies that use microorganisms with aniline-degrading abilities.

The purpose of the research is to select the microorganisms using aniline as the source of carbon or nitrogen, and to study their biodegradable ability towards aniline.

During the experiment six isolates capable of growing on aniline as a carbon source or nitrogen have been isolated from the horticultural soil with an excess of acrylonitrile up to 100 times, the sediment from the inner surface of the pipe of "Mineral fertilizers" plant communication and

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activated sludge of biological treatment plant in Perm. The isolate based on aniline (as the sole source of carbon and nitrogen) was extracted only from the activated sludge from biological treatment plant. So isolates using aniline as a carbon source or a nitrogen source were selected from samples of tube biofouling and the soil in which acrylonitrile maximum allowable concentration has been experimentally 100 times higher. The primary identification of strains was carried out. All strains were nonfermenting, gram-negative, oxidase-positive, 3 strains of 6 were catalasepositive. All isolates grew on sugars, significant increases occurred on mannose, arabinose, galactose, sucrose, citrate, maltose, ornithine acetate.

We studied growth of isolates at high aniline concentrations as a sole carbon source. Turbidity of the aqueous phase and the formation of biofilms of bacteria on hydrophobic phase of aniline were observed. Isolates may be a subject to further selection in order to increase their biodegradable ability towards aniline.

УДК 579.26

А.А. Ananko, Yu.O. Vinogradov, О.I. Bahireva

THE USE OF BACTERIA OF THE GENUS

ACINETOBACTER FOR PURIFICATION

OF NATURAL WATER

Perm National Research Polytechnic University

There are a great number of ways to control the quality and the purification of polluted natural waters from Strontium ions – chemical, electrochemical, membrane, sorbitol, etc. Each of these implies certain properties, certain fields of application and perks and flaws, usually connected to the features of apparatus formalization, consumption of substances, energy and the extra cleaning procedures. The most important modern method which has been actively developed alongside the growing interest

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towards biotechnology as a more cheap, obtainable and harmless to the environment and human is biosorption. According to this, the point of the research is segregation of microorganisms’ cells, selective to ions of Strontium for purification of the natural waters.

During the research the culture of microorganisms has been extracted from the waters of Tulva River (Perm region, Osa). According to the received results of biophysical tests, the culture was identified with the bacteria species of Acinetobacter. This established the fact that identified cells of microorganisms are capable of vital functioning under relatively high concentrations of Strontium and Calcium; and a number of hypotheses have been suggested regarding the purification process of water by using bacteria.

The first hypothesis implied that the bacteria cells can be used as a desorbing factor. To prove the hypothesis, the following experiments had been held: well-known selective sorbent ISM-S saturated with ions of Strontium in static conditions was cultivated with segregated microorganisms; the obtained material was washed with distilled water and then dissolved for the following analysis. The results are given below (Table 1).

The data shows that the culture actively accumulates its main components favoring manganese, not strontium, thus demolishing the ISM-S structure. Due to this fact the use of microorganism cells as the desorbing factor is inexpedient, although the research will continue with other sorbents.

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The second hypothesis regarding the use of extracted bacteria suggests using cells as substantive sorption material. The analysis of microorganisms selectivity in static conditions showed that in a ratio of 1:10 for ions of strontium and calcium correspondingly, the absorption degree of strontium is higher than calcium (Table 2).

T a b l e 2 The determination of selectivity for extracted culture of microorganisms

The results of the research point out the selectivity of these bacteria to ions of strontium, therefore one of the main goals in future research would be elaborating methods to obtain biosorptional material.

УДК 661

A.Y. Maksimov, N.B. Remezovskaya, E.D. Gilyova

BIOTRANSFORMATIONS CATALYZED

BY ESTERASES IN HETEROGENEOUS SYSTEMS

Perm National Research Polytechnic University

Esterases are enzymes that catalyze the hydrolytic cleavage of esters to alcohols and acids in cells. Esterases are widely used in different industries. They are used in chemical and pharmaceutical industries and they play an important role in food industry, for example in the production of flavors and aromatic substances. One of the rapidly developing

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directions of biotechnology is the use of immobilized microorganisms which consist of esterases.

Immobilization on insoluble carriers is one of the most effective methods of stabilizing cells. These systems allow using them many times with a high yield of desired products. Besides, technical solution of these processes is simpler than in the processes based on free cells.

The object of research is a strain of actinobacteria Rhodococcus erythropolis P3-8 which have carboxylesterase activity (the strain is received from the laboratory collection and isolated from the forest soil of Perm).

During the work the immobilization of the studied strain has been carried out by adsorption on CFC (catalystically fibrous carbon) on vermiculite. Conditions, parameters and efficiency of bioconversion of esters of carbonic acids (butylacetate) on free cells and on the received sorbents have also been studied.

УДК 544

N.S. Voronina, I.A. Permyakova, V.V. Volkhin

DEVELOPMENT OF STAGE OF PRETREATMENT

OF WASTE VEGETABLE OIL TO TRANSESTERIFICATION PROCESS IN THE LOW-WASTE TECHNOLOGY

OF BIO-DIESEL PRODUCTION

Perm National Research Polytechnic University

In 2015 The United Nations Climate Change Conference was held within the United Nations Convention on Climate Change, which has resulted in signing an agreement about limiting greenhouse emissions. According to this, it is necessary to limit the Earth temperature rise to 1.5°C to prevent global warming. Such a decision may have an impact on the world’s energy sector, including Russia, thus helping to reduce the

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role of fossil fuel and to increase the role of renewable energy. Therefore, the gradual replacement of traditional diesel fuel with biodiesel becomes more relevant, one of the main advantages of which is reduction of greenhouse gas emissions.

Currently, biodiesel fuels are produced by transesterification of pure food vegetable oils with low molecular weight alcohols. But there is a trend to use secondary raw materials in recent years. Therefore, waste vegetable oils can be used in the production of biodiesel. These oils are not suitable for further use in food (for example, oil remaining after cooking or expired oil).

However, such oils contain a large amount of free fatty acids. Their presence does not allow for a traditional transesterification reaction with alkaline catalyst due to their side saponification process. Therefore, this type of raw material needs the additional pretreatment step.

In our study, it is proposed to carry out pretreatment of waste cooking oils to remove the free fatty acids and their further processing by traditional technology.

The developed pretreatment technology involves change of free fatty acids from the oil phase to alcohol phase. The result of this change depends on several factors that can be optimized. To determine the influence of factors it was necessary to investigate the phase composition of reagents’ mixtures.

This process allowed the pretreatment of waste cooking oil to reduce the content of free fatty acids to the required level.

After this pretreatment the purified waste oil can be used without hindrance to conduct a transesterification reaction with a low molecular weight alcohol in the presence of an alkaline catalyst.

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УДК 615.37

L.V. Volkova, E.V. Shultz

BIOTECHNOLOGICAL APPROACHES TO OPTIMIZING

IMMUNOGLOBULINS PRODUCTION

Perm National Research Polytechnic University

The processes for the large-scale fractionation of human plasma using cold ethanol were initially developed by Edwin Cohn and his colleagues at Harvard to provide albumin as a treatment for shock during the World War II. The procedures for further purification of gamma globulins and other proteins precipitating at lower concentrations of ethanol were then developed by Oncley et al. Gamma globulin rapidly replaced convalescent and animal sera for the prevention and treatment of infectious diseases such as measles, hepatitis, and polio, then came into widespread use as a replacement therapy in the primary immune deficiencies, which emerged in the antibiotic era of the early 1950s.

Since the beginning of the 40’s and until today immunoglobulin production process has undergone several important changes. The introduction of such concepts as anticomplementary activity had a significant impact on intravenous immunoglobulin development. The combination of plasma fractionation process by cold ethanol with chromatographic steps increased purity of drug. Development of virus elimination procedures such as solvent-detergent treatment, nanofiltration led to production of a safe product.

The aim of our work is to increase the yield of immunoglobulin by modifying the existing production process.

Currently, the prediction method of specific antibodies titer of antitick immunoglobulin is under development.

The effect of time parameters of plasma fractionation process on yield of blood products will be studied, as well as a modified scheme of obtaining specific immunoglobulin will be presented.

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