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Pharmaceutical and personal care products (PPCPs) are discharged into receiving water bodies mainly from sewage treatment plants. Due to the inefficient removal in conventional wastewater treatment facilities, PPCPs have become a major concern to aquatic ecosystems, water quality, and public health worldwide since they cause harmful effects on aquatic life and human even at low doses. Among the PPCPs, carbamazepine (CBZ) is one of the most commonly prescribed anticonvulsant drugs and consumed more than 1,000 tons per year. Due to its structural complexity, CBZ is known as recalcitrant compound highly stable during wastewater treatment. Consequently, it has become one of the most frequently detected pharmaceuticals in waste water, surface water, and even drinking water. In this study, Korean indigenous microalgae strains were tested as eco-friendly and cost-effective solutions for CBZ removal. Based on the preliminary biological CBZ degradation tests, Tetradesmus obliquus KNUA061 demonstrating the best CBZ removal rate was selected for further experiments. In order to increase strain KNUA061's CBZ removal efficiency, NaOCl, which is widely accepted in the water purification process, was used as an additional stimulus to induce stress conditions. At around 20 μg L−1 CBZ, addition of 1.0 mg NaOCl resulted in approximately 20% of removal rate increase without suppressing cells growth. Roughly 90% of CBZ remained its original form and the composition of the transformed secondary metabolites was less than 10% during the biodegradation process by the microalga. Based on the results of the antioxidant enzyme activities, degree of lipid oxidation, and amino acid contents, it was concluded that the redox-defence system in microalgal cells may have been activated by the NaOCl treatment. Biomass analysis results showed that higher heating value (HHV) of strain KNUA061 biomass was higher than those of lignocellulosic energy crops suggesting that it could be utilized as a possible renewable energy source. Even though its biodiesel properties were slightly below the international standards due to the high PUFA contents, the biodiesel produced from T. obliquus KNUA061 could be used as a blending resource for transportation fuels. It was also determined that the microalgal biomass has acceptable feasibility as a sustainable dietary supplement feedstock due to its high essential amino acid contents.

Staphylococcus simulans lysostaphin is an endopeptidase lysing staphylococcus cell walls by cleaving pentaglycine cross-bridges in their peptidoglycan. A synthetic gene encoding S. simulans lysostaphin was cloned in Escherichia coli cells, and producer strains were designed. The level of produced biologically active lysostaphin comprised 6-30% of total E. coli cell protein (depending on E. coli M15 or BL21 producer) under batch cultivation conditions. New methods were developed for purification of lysostaphin without affinity domains and for testing its enzymatic activity. As judged by PAGE, the purified recombinant lysostaphin is of >97% purity. The produced lysostaphin lysed cells of Staphylococcus aureus and Staphylococcus haemolyticus clinical isolates. In vitro activity and general biochemical properties of purified recombinant lysostaphin produced by M15 or BL21 E. coli strains were identical to those of recombinant lysostaphin supplied by Sigma-Aldrich (USA) and used as reference in other known studies. The prepared recombinant lysostaphin represents a potential product for development of enzymatic preparation for medicine and veterinary due to the simple purification scheme enabling production of the enzyme of high purity and antistaphylococcal activity.

Energy from biomass is becoming increasingly important as fossil fuel reserves diminish. The utilization of biomass is already prevalent in the domestic heating sector, but produces significant amounts of pollutants that are detrimental to human health. Dioxins, formed in any combustion process where carbon, oxygen and, chlorine are present, are a subject of major interest due to their carcinogenicity. Much research has been carried out to study emissions from hazardous and municipal waste incinerators. Dioxin emission from wood combustion plants are also of interest, especially those due to combustion of treated, varnished or PVC-coated wood, which can produce high polychlorinated dibenzofurans (PCDD/F) emissions. This study compares the PCDD/F emissions produced by burning treated wood and virgin wood to verify if the differences are significant. Six different wood samples were analysed (three of treated wood and three of virgin wood) and a two-step wood gasification boiler was used. The analysis has been conducted both on off gas and on ashes. The measured PCDD/F concentrations are to be considered particularly limited and the treated wood use does not cause a general worsening in the PCDD/F emission. Thus, the wood treatment – subject of study – is not dangerous for PCDD/F. Finally, the experimental results indicated that during the thermal treatment, the formation mechanism of PCDD/F is the de novo synthesis.

Background. One of the alternative sources of obtaining biologically active substances is a culture of plant cells in vitro. The objective of this work is to introduce Artemisia vulgaris in the callus culture. The plant grows in Central Yakutia, known as a species with a high content of various biologically active substances used in traditional medicine and widely spread on a territory researched. Materials and methods. The phytomass of Artemisia vulgaris L. was collected during the expeditions on the territory of Amga’s region of the Republic of Sakha (Yakutia) in June-July 2016–2018. For introduction of Artemisia vulgaris L. into a callus culture, the actual leaves of sterile plants were used as explants. The plants were obtained via cultivating the seeds of a wild plant in controlled conditions. The cultivation was performed on a Murashige-Skoog nutrient medium with the use of two different growth regulators: 2,4-dichlorophenoxyacetic acid and kinetin, 6-benzylaminopurine and α-naphthylacetic acid. Morphological analysis of cells of the obtained calli was performed using a light microscope. The obtained primary calli were selected for further transplantation on a Murashige-Skoog nutrient medium with different concentrations of growth regulators. The growth dynamics of the callus wet mass was studied during one cycle (21 days). Results. The biomass of primary callus Artemisia vulgaris L. in the Murashige- Skoog nutrient medium with supplementation of 2,4-dichlorophenoxyacetic acid and kinetin was light yellow in color and had a dense consistency, and with the addition of 6-benzylaminopurine and α-naphthylacetic acid, it was also pale yellow in color, but with easily separable loose structure. Morphological analysis of cells of primary callus obtained showed the predominance of round-ovoid cells with a distinct nucleus. In a nutrient medium supplemented with 2,4-dichlorophenoxyacetic acid, kinetin, and α-naphthylacetic acid, the peak increase in callus wet mass was observed on day 11 after transplantation. On a nutrient medium supplemented with 2,4-dichlorophenoxyacetic acid, α-naphthylacetic acid, and 6-benzylaminopurine the peak increase in the callus wet mass was observed on the 14th day. Conclusions. The primary callus of Artemisia vulgaris L. were obtained from leaf explants taken from sterile plants. A nutrient medium with growth regulators was optimized to obtain callus and for a further introduction of Artemisia vulgaris in the callus culture. On a nutrient medium supplemented with 2,4-dichlorophenoxyacetic acid, α-naphthylacetic acid, and 6-benzylaminopurine callus biomass of Artemisia vulgaris L. is three times heavier than the biomass of callus obtained on a nutrient medium with 2,4-D, kinetin, and NAA. The obtained callus cultures had a soft, easily separable, loose structure, pale yellow in color.

The present study was conducted to assess the effect of elevated ozone stress on the development and metabolite contents of lemongrass, a medicinal plant. The experimental plant was exposed to two elevated ozone concentrations (ambient + 15 ppb, and ambient + 30 ppb) using open-top chambers. Samplings were carried out at 45 and 90 days after transplantation (DAT), for the analysis of different characteristics, while the metabolite contents of leaves and essential oils were analyzed at 110 DAT. Both the doses of elevated ozone had notable negative effects on the carbon fixation efficiency of plants, resulting in a significant reduction in plant biomass. Enzymatic antioxidant activity increased during the second sampling, which suggests that the scavenging of reactive oxygen species was more prominent in lemongrass during the later developmental stage. The results of the present study showed a stimulated diversion of resources towards the phenylpropanoid pathway, which is made evident by the increase in the number and contents of metabolites in foliar extract and essential oils of plants grown at elevated ozone doses, as compared to ambient ozone. Elevated ozone not only upregulated the contents of medicinally important components of lemongrass, it also induced the formation of some pharmaceutically active bio compounds. On the basis of this study, it is expected that increasing ozone concentrations in near future will enhance the medicinal value of lemongrass. However, more experiments are required to validate these findings.

In this research, we present an automatic speaker recognition system based on adaptive orthogonal transformations. To obtain the informative features with a minimum dimension from the input signals, we created an adaptive operator, which helped to identify the speaker’s voice in a fast and efficient manner. We test the efficiency and the performance of our method by comparing it with another approach, mel-frequency cepstral coefficients (MFCCs), which is widely used by researchers as their feature extraction method. The experimental results show the importance of creating the adaptive operator, which gives added value to the proposed approach. The performance of the system achieved 96.8% accuracy using Fourier transform as a compression method and 98.1% using Correlation as a compression method.