DEGRADATION OF REACTIVE DYES USING IMMOBILIZED PEROXIDASE PURIFIED FROM NIGELLA SATIVA

The present study was aimed to exploit the free and immobilized peroxidase from Nigella sativa seeds to degradation of textile dyes polluting the environment and water. The optimum conditions for extracting the enzyme from the Nigella seeds were determined and the highest specific activity of the enzyme was obtained 1750 units / mg protein when extracting the enzyme from the ground seeds at a ratio of 1:20 (w: v) with sodium acetate buffer at 0.2 M and pH 5.0 for 15 minutes. The enzyme was purified using two steps including the concentration by sucrose and gel filtration by using Sephadex G-150. The results shown an increase in final purification folds 2.8 time with an enzyme yield of 35%. The immobilization of peroxidase were done by entrapment method using Ca- alginate and the immobilization ratio was reached to 49%. The removal efficiency of dyes by crude enzyme (free, immobilized) and partial purified peroxidase were studied with textile dyes such as yellow, red, black and blue dyes at optimum conditions pH 5, temperature 37oC after 3 hr. Maximum removal efficiency of dyes observed with crude peroxidase and reached (76.9, 88.7, 91 and 88) % respectively. These results were close to the efficiency of the purified enzyme in removing the four dyes, while the efficiency of the crude immobilized enzyme in removing the dyes was about (70, 81, 72 and 56.4)%, respectively.

Recovery of high specific activity molybdenum-99 from accelerator-induced fission on low-enriched uranium for technetium-99m generators

A new process was developed to recover high specific activity (no carrier added) 99Mo from electron-accelerator irradiated U3O8 or uranyl sulfate targets. The process leverages a novel solvent extraction scheme to recover Mo using di(2-ethylhexyl) phosphoric acid following uranium and transuranics removal with tri-n-butyl phosphate. An anion-exchange concentration column step provides a final purification, generating pure 99Mo intended for making 99Mo/99mTc generators. The process was demonstrated with irradiated uranium targets resulting in more than 95% 99Mo recovery and without presence of fission products or actinides in the product.

A Novel Telescoped Kilogram-Scale Process for Preparation of Obeticholic Acid

A novel scalable four-step process has been developed to improve the synthesis of obeticholic acid (OCA). The key step of this process was the isolation of the amide intermediate, which underwent hydrogenation, basic epimerization, ketone reduction, and amide hydrolysis in a one-pot procedure. The use of efficient single recrystallization for the final purification in this process made the corresponding work-up procedure more concise and environmentally friendly. A kilogram-scale production of OCA following this process could achieve over 70% yield with all impurities controlled below 0.10%.

Optimization of tobacco seed cleaning modes

The process of obtaining high-quality tobacco seeds is very laborious, and at present many operations are performed manually at All-Russian Research Institute of Tobacco, Makhorka and Tobacco Products. The process of obtaining tobacco seeds at the Institute consists of the following operations: harvesting of inflorescences, drying of inflorescences, destruction of inflorescences, screening out coarse impurities, final cleaning in an air stream. An attempt was made earlier to mechanize and improve working conditions at the stage of final purification of the seed mixture. A unit for the final purification of tobacco seeds was developed, manufactured and tested. In this article other modes of final purification of the tobacco seed mixture to improve mechanization and productivity of the same unit have been tested. The seed mix of the 2019 harvest has been used in the studies. Coarse impurities have been separated from the seed mix by sieving through sieves with different hole sizes. Earlier modes of double final purification of seed mixture were proposed. In this research the previously proposed double cleaning modes have been taken as control ones, and in the experiment three-fold modes with a higher feed rate of the seed mixture have been used. As a result, the experimental modes provide identical removal of contaminants, however, the productivity of the unit increases 2 – 3 times due to the shorter total duration of purification, and mechanization is also improved due to a more uniform flow of the seed mixture. In this case, there is no need for the constant presence of an operator, and the process of final purification of the tobacco seed mixture is reduced only to its loading and unloading.

Expression, solubilization, refolding and final purification of recombinant proteins as expressed in the form of "classical inclusion bodies" in E. coli

: Escherichia coli has been most widely used for production of the recombinant proteins. Over-expression of the recombinant proteins is the mainspring of the inclusion bodies formation. The refolding of these proteins into bioactive forms is cumbersome and partly time-consuming. In the present study, we reviewed and discussed most issues regarding the recovery of "classical inclusion bodies" by focusing on our previous experiences. Performing proper methods of expression, solubilization, refolding and final purification of these proteins, would make it possible to recover higher amounts of pro-teins into the native form with appropriate conformation. Generally, providing mild conditions and proper refolding buffers, would lead to recover more than 40% of inclusion bodies into bioactive and native conformation.

The use of higher aquatic vegetation for airports wastewater final purification

It has been shown that with air transportation rise it is necessary to increase the efficiency of storm and wastewater purification from the territory of the airports and other air enterprises. It is suggested to use higher aquatic vegetation to protect the environment from airborne pollutants into natural water reservoirs. For further step of final cleanup it is proposed to use aquatic hyacinth – Eichornia. The rationalization for the plant selection is provided, its essential characteristics and the way for extracting pollutants out of the aquatic environment during the metabolism process are described. The technique of experiments on determining the effectiveness of biological wastewater purification within the conditions of the central part of the country is discussed in terms of Moscow region. The measurement results of suspended materials and petrochemicals concentrations in water before and after purification in sediment ponds are presented. The effectiveness of biological purification is shown. The possibility of using water hyacinth for purification of some superficial water reservoirs is also outlined. It is recommended all the year round to use protecting constructions (covers) in open purification plants, then under protected conditions metabolism processes can proceed in the rhizome, stems and foliage of the vegetation even in the autumn-winter period. It is proposed to recycle the used biomass for commercial purposes as a livestock fodder additive under the certain conditions that have been defined. The algorithm of preserving seedlings in the cold season and their subsequent planting in water reservoirs in spring is discussed. It is economically feasible to use biological final purification by aquatic hyacinth but observing the unusual environmental safety measures that have been formulated is required. Practicability of further prospective work on producing specialized ecosystems involving higher aquatic vegetation for nature-like integrated purification of certain types of wastewater was underlined.

Development of Purification Process Using Electrocoagulation Technique for Biodiesel Produced via Homogeneous Catalyzed Transesterification Process of Refined Palm Oil

This work is focused on the preliminary development of purification process using electrocoagulation technique for biodiesel produced via homogeneous catalyzed transesterification process of refined palm oil (RPO) to shorten the separation process and reduce the water consumption during the final purification with water-washing process. Biodiesel as Fatty acid methyl esters (FAMEs) were produced via transesterification reaction of RPO as feedstock with methanol in the presence of sodium hydroxide derivative-catalyst at the optimal condition using conventional heating. Electrocoagulation separation process was in-house designed to investigate the effects of electrode configurations such as shapes, distances between electrodes and suitable applied AC high voltages (ranging from 1 to 9 kV) on the separation efficiency of glycerol and biodiesel. Results revealed that with the electrocoagulation process at room temperature using AC electrical current at high voltage of 3 kV (and low amperage) with a point to point electrode configuration and the vertical-distance between electrodes of 3 cm was very efficient and achieved higher free glycerol removal than using the conventional separation of the gravitational settling. Furthermore, the separation time was significantly shortened from typically > 24 h with the gravitational settling to 240 s (4 min) and the number of water-washing was reduced from 5 to 3 times during the final purification process. The final purity of biodiesel was 98.89%±0.25% with high quality according to standards of EN 14214 and ASTM D6751.