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Number of results: 77
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Abstract

The purpose of the present work was to estimate the effectiveness of grapefruit extract and Pythium oligandrum in protection of common bean, runner bean and pea from soil-borne pathogenic fungi. The investigated preparations were used for seed dressing and spraying plants at the beginning of anthesis. The results pointed out that the applied products considerably improved emergence, healthiness and yielding of the examined plant species. Besides, Biosept 33 SL showed a better effect than Polyversum. Independently on the species, the fewest plants, with the greatest proportion of infected ones and the smallest yield of seeds were obtained from the untreated control. Alternaria alternata, Fusarium spp., Pythium irregulare, Rhizoctonia solani and Sclerotinia sclerotiorum were frequently isolated from infected roots and stem bases as well as from seeds of bean and pea. Fusarium oxysporum tuned out to be dominant. The proportion of the above listed fungi in the treatments with Biosept 33 SL or Polyversum was smaller than in the control. At the same time, the role of those fungi in infecting the plants of common bean, runner bean and pea treated with Biosept 33 SL was only a little smaller than after using Polyversum.

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Authors and Affiliations

Elżbieta Patkowska
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Abstract

Toxicity and physiological alterations were determined in Pseudococcus viburni nymphs treated with Artemisia annua methanolic extract. The leaf dipping bioassay showed LC50 values of 0.287% and 0.194% 24 and 48 hours post-exposure. Activities of general esterases were significantly higher in the control nymphs than in those which had been treated except for the 48 h time interval using α-naphtyl acetate. The activity of glutathione S-transferase using CDNB (1-chloro-2,4-dinitrobenzene) in the control nymphs, was significantly higher than in the control at both time intervals while no significant difference was observed after 24 h in addition to the higher enzymatic activity in the treated nymphs after 48 h. All three aminotransferases were significantly more active in the control nymphs except for time intervals of 24 h for γ-glutamyl transferase and 48 h for alanine aminotransferase. Higher activities of lactate dehydrogenase, acid- and alkaline phosphatase were found in the control nymphs than in treated nymphs for all time intervals. Activities of the enzymes involved in the antioxidant system including catalase, peroxidase, superoxide dismutase, ascorbate peroxidase and glucose-6-phosphate dehydrogenase was increased in the treated nymphs compared to the control. Results of the current study demonstrated toxic effects of A. annua methanolic extract on P. viburni nymphs causing mortality and physiological turbulences.

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Authors and Affiliations

Samar Ramzi
Ali Seraji
Reza Azadi Gonbad
Kimia Mirhaghparast
Zahra Mojib-Haghghadam
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Abstract

Elevated content or heavy metals in soils is characteristic of the Dąbrowa Górnicza region. The highest concentrations of lead. cadmium and zinc exceed herc 650, 15, and 1000 mg/kg of soil, respectively. Samples of soi I from selected sites underwent the speciation analysis with the use of the Tessier method. modified according to Kersten and Forstner. Results of the investigations proved the highest concentrations or these metals in the area of Trzebiesławice. They occur here in the strongly bound forms and, mainly, their occurrence is related to presence of limestone rocks. The greatest amounts of these metals in easily assimilable to plant forms occur within the area of the town of Dąbrowa Górnicza. The most probable source ot· most of these heavy metals in soils are here contaminants emitted by the industry, mainly by the metallurgy. In the vicinity of the town of Błędów, mainly sandy soils occur, characteristic or which is low content of considered metals. Weak sorption capacities of these soils account for relatively good cxtractability of the three metals. In soils from the Lęka area, strong binding of these metals was confirmed. Occurrence or cadmium should be of special attention because this metal occurs as built in the crystal lattice of minerals.
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Authors and Affiliations

Bronisław Wyżgolik
Stanislaw Karweta
Ewa Surowiec
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Abstract

Natural resources and the extractive industries play a central role in the economy of developing countries and the lives of nearly half of the world’s population. The increasing demand for oil, gas, and mineral resources has led some countries to prioritize the extractive industries; yet, there is growing empirical evidence that in some cases governments have neglected other sectors of the economy, making them highly dependent and vulnerable to volatile commodity prices. Latin American countries face the challenge of changing their model of primary-export specialization and move away from their dependence on natural resource-intensive exports in order to avoid being vulnerable to commodity cycles. In this context, given the limited literature available on measuring the dependence on the extraction of oil, gas and minerals of the Ecuadorian economy, the objective of this article is to twofold. First, to provide a snapshot of the historical and current situation of Ecuador’s natural resource dependence. Second, to estimate the Extractives Dependence Index (EDI) scores for Ecuador for the years 2003 to 2017. The EDI is a generally accepted method for measuring a country’s aggregate dependence on natural and mineral resources. Based on the EDI scores obtained, we analyze the variation of this indicator and investigate the effect of extractives dependence on the Ecuadorian economy. Results show that despite the government’s significant efforts to diversify Ecuador’s economy, the country has a persistent dependence on the extractive sector.

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Authors and Affiliations

Pablo Benalcazar
Luis Felipe Orozco
Jacek Kamiński
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Abstract

For much of the last two decades, the Central and East European (CEE) economies have experienced a deep structural reform, moving away from a socialist economic system towards a market economy. The political situation of the second half of the 20th century had a significant impact on the economic development and competitiveness of these transition countries, when compared with their Western European counterparts. A vast number of studies have been conducted to analyze the structural changes required for resource-dependent economies to achieve long-term development and to understand the synergies between commodities and diversification. Yet, the dynamics of resource extraction and the resource dependence of regions that have experienced periods of sustained levels of growth have largely been overlooked, especially the Central and Eastern European region. In this context, this article presents an analysis of the level of resource dependence of six countries which joined the European Union between 2004 and 2007. Using data spanning from the year 2000 to 2017, we calculate the Extractives Dependence Index (EDI) of six former Soviet satellite nations and one former Soviet state. Our results indicate that the commodity structure of trade in the six countries which joined the European Union has changed considerably. These countries have reduced their economic dependence on extractive resources by developing their high value-added and technology-intensive sectors. Our findings also reveal that Poland experienced the highest decrease in EDI scores among the six CEE countries.

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Authors and Affiliations

Marcin Malec
ORCID: ORCID
Pablo Benalcazar
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Abstract

This study investigates the acaricidal, ovicidal, and repellent effects of the Tagetes patula Linn. (Asteraceae) leaf extract against both the adult female and egg stages of Tetranychus urticae Koch (Trombidiformes: Tetranychidae) under laboratory conditions. The Tagetes patula ethanolic leaf extract [TpEtOH70%] was screened for adulticide and ovicide bioassays in order to consider its acute toxicity. One sublethal concentration was used to assess egg-laying capacity (fecundity), repellent, and oviposition deterrent activities. The chemical characterization was conducted by gas chromatography-mass spectrometry (GC-MS) analysis to identify the TpEtOH70% bioactive components. Results showed that the LC50 value of TpEtOH70% leaf extract predicted by Probit analysis against T. urticae adult females at 24 h was 0.99%. The TpEtOH70% leaf extract showed a significant toxic effect as the highest mean mortality rates (± SE) of the treated adult females was 88.9 ± 3.7%. However, the TpEtOH70% leaf extract was insignificant in affecting the egg-laying capacity of the adult females treated with a sublethal dose of 0.5% even after 72 h. The TpEtOH70% leaf extract was classified repellent since the repellent index (RI) value was lower than 1 – SD. In addition, it had a high oviposition deterring effect based on a 100% reduction of the total number of eggs. The TpEtOH70% leaf extract had a significant ovicidal effect on T. urticae eggs, with 56.04% reduction in hatching. Five bioactive compounds from various classes of phytochemicals were identified in the TpEtOH70% leaf extract and the major compound was phytol (62.72%). This pioneering investigation reveals the adulticidal, ovicidal, and repellent activities of the TpEtOH70% leaf extract against T. urticae. A combination of multiple modes of action of different plant components may act alone or in synergism to delay the development of mite resistance.

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Authors and Affiliations

Manal Sayed Mohamed Ismail
Hend Maroof Tag
Marguerite Adly Rizk
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Abstract

We used DPPH scavenging assays to study the antioxidant activity of three native Polish species of blackberry leaves (Rubus kuleszae Ziel., R. fabrimontanus (Sprib.) Sprib. and R. capitulatus Utsch.). All the studied extracts (methanolic, water, methanolic-water) showed high DPPH free radical scavenging activity (IC50 450.0-186.0 μg/ml). The most effective of the studied species was Rubus kuleszae. Total content of phenolic compounds (70.50-136.04 mg GAE/g) and phenolic acids (14.70-38.26 mg CAE/g) was determined spectrophotometrically. Antioxidant activity correlated positively with total content of phenolic compounds and phenolic acids.

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Authors and Affiliations

Anna Gawron-Gzella
Marlena Dudek-Makuch
Irena Matławska
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Abstract

Steroidal saponins isolated from many plant species belonging to Monocotyledones display potent cytotoxic activity towards many human tumor cells. We examined the cytotoxic effects of crude Paris quadrifolia extract for the first time, testing isolated saponin-rich fractions against four different human cell lines using the [(3-(4,5-dimethylthiazol-2-yl)]-2,5-diphenyltetrazolium bromide (MTT) assay. Cytotoxic activity was tested against human promyelocytic leukemia (HL-60) cells, human cervical adenocarcinoma (HeLa) cells and human breast cancer (MDA-MB-468) cells. Human skin fibroblasts were used as non-neoplastic control cells. Our results show significant activity of the weakly water-soluble solid residue and butanolic fraction against HL-60 and HeLa cells. The solid residue exerted cytotoxicity against all tested cell lines.

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Authors and Affiliations

Justyna Stefanowicz-Hajduk
Anna Kawiak
Jerzy Gajdus
J. Ochocka
Monika Paszkiewicz
Piotr Stepnowski
Ewa Łojkowska
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Abstract

This work presents a comparative analysis of the phenolic composition (UHPLC-PDA-ESI-MS3, HPLC-PDAfingerprint, UV-spectrophotometric methods) and antioxidant activity (DPPH, FRAP) of leaf samples from two vegetation seasons of a medicinal and dietary plant Sorbus domestica growing in its natural habitat (Croatia, C) and cultivated in Poland (P). The samples from both sources were rich in structurally diverse polyphenols (44 analytes; P: 73.4–76.6 and C: 98.3–106.7 mg GAE/g dry leaves) including the dominating flavan-3-ols and flavonoids. The greatest qualitative and quantitative differences were observed for flavonoids (P: 14.3–20.3%; C: 27.5–34.1% of polyphenols) – in the Polish samples flavonoid diglycosides predominated, in the Croatian samples the contents of both monoglycosides and diglycosides were similar. In the case of dry methanolic extracts, despite the higher extraction efficiency obtained for the Croatian samples (32–36% vs 23–24%), the quality of the extracts was comparable, both in terms of the total phenolic content (P: 269.4–280.0; C: 297.6–304.4; mg GAE/g dry extract) and antioxidant activity parameters (DPPH, EC50, μg/mL. P: 10.5–10.9, C: 10.0–10.3; and FRAP, mmol Fe2+/g, P: 6.64–7.13, C: 7.06–7.11). As a result, the study confirmed the influence of environmental conditions on the phenolic profile and antioxidant capacity of S. domestica leaves, as well as showed that despite some differences, plant materials from both Poland and Croatia might be suitable for production of natural health products.

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Authors and Affiliations

Magdalena Rutkowska
Monika Dubicka
Monika A. Olszewska
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Abstract

Coal mining activities carried out for 200 years in Upper Silesia have had a negative effect on buildings. T his impact is in all cases related with continuous deformations of the surface and in certain cases with discontinuous deformations (mostly cave-ins), changes in water relations and mining tremors. T he paper presents an evaluation of the impact of a mining activity on a building situated in the Upper Silesian Coal Basin. T he building was affected by continuous deformations and mining tremors. Calculations were made of the values of deformation rates by means of Budryk–Knothe’s theory, which were partly verified on the basis of the results from geodetic measurements. An analysis of the velocity and acceleration of basement vibrations caused by mining-induced tremors was also conducted. T he conclusions included a high consistency between the results obtained on the basis of calculations and the values obtained by means of PGA and PGV measurements. In the case of tremors with the highest energy in the hipocentrum, there an empirical formula allowing for calculation of PGA value in given geological and mining conditions was also proposed. T he application range of the formula mentioned above is obviously limited only to the conditions in consideration. The presented conclusions indicate that at present, sufficiently precise methods, allowing for calculations for practical purposes, not only of deformation indices’ values, but also of PGV and PGA values, presently exist.

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Authors and Affiliations

Piotr Strzałkowski
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Abstract

The aim of the study was fractionation of Zn, Cu, Ni, Pb in the bottom sediments of two small reservoirs: at Krempna on the Wisłoka River and at Zcslwicc on the Dlubnia River. The partitioning of metals for various fractions was performed with the use of Tessier's sequential chemical extraction method. All together five metal fractions were distinguished: exchangeable metals (fraction I), metals bound to carbonates (fraction II), metals bound to hydrate Fe-Mn oxides (fraction III), metals bound to organic matter (fraction IV), and metals bound to minerals (fraction V). The largest quantities of metals were bound with fraction V, the smallest occurred in the forms most easily available for living organisms, in faction I. Proportions ofZn, Ni and Pb in the exchangeable fraction were about 1%. The amounts of metals bound with fraction II were also relatively low, except lor Zn in bottom sediment at the Zeslawice Reservoir. In this bottom sediment the share of Zn bound to carbonates was 33%. Medium metal quantities were associated with hydrate Fe-Mn oxides (fraction III) and with organic matter (fraction IV). Relatively high proportion ofmetals in fraction V and trace amounts ofmetals in fraction I as well as alkaline and neutral reaction of the sediments may prove a potentially low hazard of the metal release in the case of chemical changes in the reservoirs.
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Authors and Affiliations

Marek Madeyski
Marek Tarnawski
Czesława Jasiewicz
Agnieszka Baran
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Abstract

Stevia rebaudiana Bertoni which has gained industrial and scientific interests is a suitable nutritional alternative to sucrose as a sweetener. Recently, there have been studies which show the extraction of this phytochemical substance from stevia leaves and purification methods by several alcohols and chromatographic methods. However, these methods are not cost-effective. Therefore, an attempt was made to extract and purify ST using inexpensive, scalable and simple techniques where different steps like extraction, electrocoagulation, ion exchange, activated charcoal, vacuum evaporation and butanol wash were used as purification steps. The present study established a new improved technology of extraction of ST from stevia leaves using water as a solvent followed by various purification steps. 496 mg of Stevioside extracted in the form of crystals was obtained from 100 g of leaves which is 10 times more than the reported yield of 54 mg from 100 g stevia leaves in literature. This methodology can be scaled up at the industry level for future large production to meet the huge demand for natural sweeteners.
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Authors and Affiliations

Jignesh Joshi
1 2
Alok Gautam
3 2
Shina Gautam
3 2

  1. Chemical Engineering Dept, Government Engineering College, Valsad, Gujarat, India-382424
  2. Gujarat Technological University, Chandkheda, Ahmedabad, 382424 Gujarat, India
  3. Chemical Engineering Dept, Shroff S. R. Rotary Institute Of Chemical Technology, Bharuch 393135, Gujarat, India
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Abstract

Antibiotics are used for postsurgical wound healing purposes but unfortunately, resistance against them demands some alternatives for quick recovery. Sepsis of wounds is a challenge for medical as well as veterinary professionals. Nanoparticles have significant advantages in wound treatment and drug resistance reversal. This study was conducted to appreciate emerging alternates of antibiotics like zinc oxide nanoparticles and plant extracts in topical application. Zinc oxide is considered a good wound healer and its nanoparticles are easy to access. So, the efficacies of zinc oxide nanoparticles and sweet flag plant extract ointments were tested to compare modern and traditional therapeutics as sweet flag is considered a pure medicinal plant. Rabbits were selected for this study due to the healing properties of their skin. Wounds were inflicted on the thoracolumbar region and treated for 29 days post-surgically daily with normal saline and the ointment of zinc oxide nanoparticles and sweet flag extract ointment, prepared in a hydrophilic solvent. Wound shrinkage was observed daily and histopathological analysis was made and results were compared. Zinc oxide nanoparticles ointment showed the most satisfactory results for every parameter included in the study. No side effects of its topical application were observed. Healing was normal without any complications. The preparations of zinc oxide nanoparticles may help in the era of antibiotic resistance as topical drugs in the future.
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Authors and Affiliations

A. Abbas
1 2
S.A. Muhammad
3
A. Ashar
4
S.A. Mehfooz
2
A. Rauf
3
M. Bakhsh
3
T. Nadeem
5
H. Fu
1

  1. Department of Pharmacy, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
  2. Department of Clinical Medicine and Surgery, University of Agriculture, Faisalabad 38000, Pakistan
  3. University of Veterinary and Animal Sciences, Lahore, CVAS Jhang 35200, Pakistan
  4. Wilson College of Textiles, North Carolina State University, North Carolina, USA
  5. University of Veterinary and Animal Sciences, Lahore, Para Veterinary Institute (PVI), Karor 31100, Layyah, Pakistan
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Abstract

Herpesviruses (HV) are pathogens causing infections in humans and animals worldwide. Since it shares many common features with other HV, bovine HV type 1 (BoHV-1) was selected as a model to test the anti-herpesviral activity of medicinal plants.

Fifteen plants were chosen in this study for their medical, antibacterial and antiviral properties. The aim was to investigate ethanolic extracts from the selected medicinal plants for anti-BoHV-1 activity. The virucidal activities were evaluated by comparing the effect of noncytotoxic concentrations of extracts on BoHV-1 strain 1640 replication in Madin-Darby bovine kidney (MDBK) cells. Virucidal activity was determined by means of virus titration after exposure to the extracts. The extract of Desmodium canadense was found to be the most effective virucide – the 50% tissue culture infective dose (TCID50) after exposure was 3.75 log10 and the virus reduction factor was ≥5.0±0.25 log10. The extract of D. canadense was therefore chosen for further studies. Virus yield reduction assays showed that D. canadense extract had time-dependent and dose-dependent effects. It effectively reduced virus titre from 8.33 log10 to 4.67 log10 (p<0.01). The virucidal activity was also confirmed by real-time polymerase chain reaction (real-time PCR), where the number of threshold cycles (Ct) was inversely proportional to the virus titre in TCID50 The virucidal activity was also confirmed by real-time polymerase chain reaction (real-time PCR). This method showed that the number of threshold cycles (Ct) was inversely proportional to the virus titre (direct correlation with exposure time R=0.9321). The extract of D. canadense showed a high virus reduction capacity. In future, such active substances should be identified for the development of effective antivirals.

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Authors and Affiliations

R. Lelešius
P. Girdauskaitė
A. Karpovaitė
R. Mickienė
T. Drevinskas
N. Tiso
O. Ragažinskienė
L. Kubilienė
A. Maruška
A. Šalomskas
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Abstract

Despite many phytochemical and pharmacological investigations, to date, there are no reports concerning the antibabesial activity of extracts of A. millefolium against B. canis. This study was aimed at investigating the biological activities of A. millefolium against the Babesia canis parasite and to identify its chemical ingredients. The water (WE), ethanol (EE) and hexane/acetone (H/AE) extracts of plant aerial parts were screened for total phenolic content (TPC), total flavo- noid compound (TFC), DPPH free radical-scavenging activity and its antibabesial activity assay. In this study, imidocarb diproprionate was used as a positive control. The H/AE and EE extracts were analysed using gas chromatography–mass spectroscopy (GC–MS).

In the EE extract, the main compounds were 17.64% methyl octadec-9-ynoate, 16.68% stigmast-5-en-3-ol(3α,24S) and 15.17% hexadecanoic acid. In the H/AE extract, the main com- pounds were 34.55% 11-decyldocosane, 14.31% N-tetratetracontane, 8.22% β-caryophyllene, and 7.69% N-nonacosane. Extract of EE contained the highest content of phenolics followed by H/AE and WE. The concentration of flavonoids in EE, H/AE and WE extracts showed that TFC was higher in the EE samples followed by H/AE and WE. The antioxidant activities were highest for AA, followed by EE, WE and H/AE. The antibabesial assay showed that the WE, EE and H/AE extracts of A. millefolium were antagonistic to B. canis. At a 2 mg/mL concentration, it showed 58.7% (± 4.7%), 62.3% (± 5.5%) and 49.3% (± 5.1%) inhibitory rate in an antibabesial assay, respectively.

Considering these results, the present findings suggest that A. millefolium extracts may be a potential therapeutic agent and that additional studies including in vivo experiments are essential.

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Authors and Affiliations

L. Guz
Ł. Adaszek
J. Wawrzykowski
J. Ziętek
S. Winiarczyk
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Abstract

Individual identification of similar communication emitters in the complex electromagnetic environment has great research value and significance in both military and civilian fields. In this paper, a feature extraction method called HVG-NTE is proposed based on the idea of system nonlinearity. The shape of the degree distribution, based on the extraction of HVG degree distribution, is quantified with NTE to improve the anti-noise performance. Then XGBoost is used to build a classifier for communication emitter identification. Our method achieves better recognition performance than the state-of-the-art technology of the transient signal data set of radio stations with the same plant, batch, and model, and is suitable for a small sample size.
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Authors and Affiliations

Ke Li
1 2 3
ORCID: ORCID
Wei Ge
1 2
ORCID: ORCID
Xiaoya Yang
1 2
Zhengrong Xu
1

  1. School of Information and Computer, Anhui Agricultural University, Hefei, Anhui, 230036, China
  2. Anhui Provincial Engineering Laboratory for Beidou Precision Agriculture Information, Anhui Agricultural University, Hefei, Anhui, 230036, China
  3. Key Laboratory of Specialty Fiber Optics and Optical Access Networks, Shanghai University, Shanghai, 200072, China
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Abstract

The market value of essential oils is steadily increasing every year. They are mainly used as aromas and preservatives in food and cosmetics industries. The content and yield of the obtained extracts change across the seasons of the year. The knowledge of these differences is important for essential oils industry to gain the best quality and quantity of products. In this study Thuja occidentalis L. (Eng. northern white cedar) extract was obtained from leaves by maceration in dichloromethane. Plant material was collected during each season of the year and the finished products were thoroughly examined through GC-MS analysis. The seasonal variations of volatile compound composition showed that the most adequate period to obtain T. occidentalis extract on an industrial scale is spring. This is due to the best efficiency (almost 10%) and the highest content of monoterpenes (67%).
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Authors and Affiliations

Marek Chajduk
1
Marek Gołębiowski
1

  1. Laboratory of Analysis of Natural Compounds, Department of Environmental Analysis, Faculty of Chemistry, University of Gdańsk, ul. Wita Stwosza 63, 80-308 Gdańsk, Poland
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Abstract

The use of foam fractionation followed by aqueous two-phase extraction has emerged as a potential alternative to traditional liquid chromatography, hitherto irreplaceable in the purification of phycobiliproteins. The crude extracts of C-phycocyanin and allophycocyanin were obtained after Thermosynechococcus PCC 6715 biomass disintegration. The FF process with air flow of 2.4 L·h -1 resulted in purification factors up to 1.47 and partitioning coefficients of about 39, and did not require the addition of surfactants. A temperature of 35˚C allowed for the highest partitioning coefficient of 67.6 and yield of 76%; however, the purity of C-PC in condensate at this temperature was lower than at 25˚C. ATPE was tested in 20 different systems consisting of polyethylene glycol and phosphate or citrate salts, of which PEG1500-citrate gave the highest purification factor value of 2.31. Conversely, a partitioning coefficient of 2416 and 1094 were obtained for the PEG1500-phosphate and PEG3000-phosphate systems, respectively. Interestingly, the use of FF condensate in subsequent ATPE step resulted, for the first time, in the separation of the polymer phase into two fractions, one contained C-phycocyanin and the other allophycocyanin. It can be concluded that the use of a two-step system of FF and ATPE is a viable way to separate phycobiliproteins.
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Authors and Affiliations

Anna Antecka
1
ORCID: ORCID
Rafał Szeląg
1
Stanisław Ledakowicz
1
ORCID: ORCID

  1. Lodz University of Technology, Faculty of Process and Environmental Engineering, Department of Bioprocess Engineering, Wolczanska 213, 93-005 Lodz, Poland
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Abstract

The total content of lead in soil from the battery plant site was determined and a speciation analysis of this element was carried out using Rudd's method of sequential extraction. It was found out that lead is present in soil samples mostly in a low mobility organically bound form, which under certain conditions can, however, be absorbed by plants, and in a moderately mobile carbonate form. Lead was extracted from soil using sodium salt of ethylenediaminetetraacetic acid and sodium hydroxide solution and tests were also conducted to separate it from leaching solutions electrochemically. Extraction with Na2 -EDTA solution makes it possible to remove 86% of lead from soil, but the solution shows much lower lead extraction power when used for renewed leaching after having been electrochemically freed of lead. Extraction with NaOH solution gives worse results, namely only 70% of lead can be removed from soil, but the solution after having been electrochemically freed of Pb shows higher Pb leaching power when used for renewed leaching than in the case of Na2 - EDTA solution.
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Authors and Affiliations

Teofil Korolewicz
Marian Turek
ORCID: ORCID
Jerzy Ciba
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Abstract

Recently, since the demand of rare earth permanent magnet for high temperature applications such as an electric motor has increased, dysprosium (Dy), a heavy rare earth element, is becoming important due to severe bias in its production. To fulfill the increasing need of Dy, recycling offers as a promising alternative. In recycling of rare earths, Hydro-metallurgical extraction method is mainly used however it has adverse environmental effects. Liquid metal extraction on the other hand, is an eco-friendly and simple method as far as the reduction of rare earth metal oxide is concerned. Therefore, liquid metal extraction was studied in this research as an alternative to the hydro-metallurgical recycling method. Magnesium (Mg) is selected as solvent metal because it doesn’t form intermetallic compounds with Fe, B and has a low melting and low boiling point. Extraction behavior of Dy in (Nd,Dy)-Fe-B magnet is observed and effect of Mg ratio on extraction of Dy is confirmed.

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Authors and Affiliations

Sangmin Park
Sun-Woo Nam
ORCID: ORCID
Ju-Young Cho
ORCID: ORCID
Sang-Hoon Lee
ORCID: ORCID
Seung-Keun Hyun
Taek-Soo Kim
ORCID: ORCID
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Abstract

Tannic acid or tannin, type of phenolic compound contains in kenaf bast fibre. Conventional extraction has certain limitations in terms of time, energy, and solvent consumption. Ultrasound assisted extraction (UAE) can extract bioactive components in shorter time, low temperature, with lesser energy and solvent requirement. UAE as alternative extraction technique is better equipped to retain the functionality of the bioactive compounds. In this study, the conditions for ultrasound assisted extraction (UAE) of tannic acid from kenaf bast fibre by assessing the effect of sonication time and different duty cycles were optimized. The use of ultrasound to extract tannic acid from kenaf bast fiber was evaluated. Ultrasound-assisted extraction (UAE) was carried out using ethanol as solvent to intensify the extraction efficacy. Phytochemical screening was conducted to identify the presence of tannic acid in extracts. The extracts then were analyzed using High-Performance Liquid Chromatography (HPLC) and Scanning Electron Microscopy (SEM). It was found that 0.2429 mg/mL of tannic acid was obtained under the extraction conditions of extraction temperature of 40℃, sonication time of 20 minutes and duty cycle of 50%. From SEM analysis, it was found that the raw sample demonstrated rough surface and no porous but kenaf bast fibre display smoother surface with less impurities and few pores appeared after the extraction process using UAE. These results indicate that ultrasound-assisted extraction is an efficient method for extracting tannic acid from kenaf bast fibre with the advantages of lower extraction time and higher extraction yield.
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Authors and Affiliations

M. Mohamad
1
ORCID: ORCID
H.A. Ibrahim
1
M.F.M. Nasir
2
N.A. Mohidem
3
ORCID: ORCID
N.F. Shoparwe
1
P.T. Teo
1
ORCID: ORCID
M.N. Masri
1
ORCID: ORCID
A.R. Irfan
4 5
ORCID: ORCID

  1. Universiti Malaysia Kelantan, Faculty of Bioengineering and Technology, Jeli Campus, Kelantan, Malaysia
  2. National Kenaf and Tobacco Board, Kubang Kerian, Kelantan, Malaysia
  3. Universiti Putra Malaysia, Faculty of Engineering Selangor, Department of Biological and Agricultural Engineering, Malaysia
  4. Universiti Malaysia Perlis, Faculty of Mechanical Engineering Technology, Perlis, Malaysia
  5. Universiti Malaysia Perlis, Center of Excellence Geopolymer and Green Technology (CEGeoGTech), Perlis, Malaysia
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Abstract

Underground mining extraction causes the displacement and changes of stress fields in the surrounding rock mass. The determination of the changes is extremely important when the mining activity takes place in the proximity of post-flotation tailing ponds, which may affect the stability of the tailing dams. The deterministic modeling based on principles of continuum mechanics with the use of numerical methods, e.g. finite element method (FEM) should be used in all problems of predicting rock mass displacements and changes of stress field, particularly in cases of complex geology and complex mining methods. The accuracy of FEM solutions depends mainly on the quality of geomechanical parameters of the geological strata. The parameters, e.g. young modulus of elasticity, may require verification through a comparison with measured surface deformations using geodetic methods. This paper presents application of FEM in predicting effects of underground mining on the surface displacements in the area of the KGHM safety pillar of the tailing pond of the OUOW Żelazny Most. The area has been affected by room and pillar mining with roof bending in the years 2008-2016 and will be further exposed to room-and-pillar extraction with hydraulic filling in the years 2017–2019.

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Authors and Affiliations

Ewa Warchała
Anna Szostak-Chrzanowski
Paweł Stefanek
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Abstract

The extraction of mineral deposits is usually charged with additional taxes or royalty fees that go beyond the general income tax. As a rule, countries prefer stable sources of fiscal revenues based on the volume of raw material extraction, and investors prefer models based on profit tax, i.e. taking operating costs and risks lower than the expected profitability of the project into account. As a rule, too high a burden for the mining sector affects investors’ decisions regarding the introduction of new investments. There are a number of examples where excessive fiscal burdens force investors to move to countries with more favorable tax systems. An analysis of various forms of taxation of mining enterprises around the world has been presented and compared with the system implemented in Poland. Usually, the countries that apply the royalty fee in the mining sector at the same time introduce a number of adaptation mechanisms. This is crucial for new investments due to the fact that they may to some extent compensate for the high costs of transition from the investment to the operational phase. In most cases, several incentive mechanisms are used at the same time, e.g. the accelerated settlement of investment expenditures and the unlimited settlement of losses. The copper and silver mining tax introduced in Poland increased the discounted effective tax rate (ETR) from 38.5% to 89% for the entire investment period, which resulted in a 11-year return on investment, as well as a drop in the internal rate of return (IRR).There are currently no mechanisms in Poland which would balance the burden of this tax for a new investor. In order to balance the extraction tax for certain minerals in terms of the IRR and ETR key indicators, the introduction of several adaptation mechanisms has been proposed. For new investments the most essential mechanism is the preferential settlement of capital expenditures incurred in the pre-production phase of an investment. The others include accelerated amortization, the ability to deduct certain expenses for the exploration phase from the tax base, along with an extended tax loss settlement period, or a mechanism for deducting a certain percentage of investment expenses directly from the tax.

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Authors and Affiliations

Stanisław Speczik
Kinga Capik
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Abstract

Mining wastes are by-products generated during search, excavation and processing, both physical and chemical, of ores and other minerals. In 2017, wastes from group 01 constituted 60% of total wastes produced in Poland. According to the statistical data, approximately 92% of the waste generated during the excavation and processing of hard coal is economically reused. 30% of this waste used in industry and nearly 70% is used for the reclamation of the degraded industrial areas. At present, there is a tendency in the E uropean Union to shift from a linear economy to the Circular E conomy. The goal is to maintain economical value of the resources, among others, by their reuse in a productive way, which at the same time eliminates waste. One of the industrial branch where the ideals of a Circular E conomy can be implemented is the mining industry. Mining wastes may form one of the sources of anthropogenic minerals, as they belong to alternative aggregates. Deposits of anthropogenic minerals are considered sources of valuable raw materials which guarantee that the products made on their basis will be of high quality. The article presents the results of physico-chemical tests, the leachability of contaminations and phytotoxicity tests carried out on the basis of the selected mining waste in light of a Circular E conomy.

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Authors and Affiliations

Monika Czop
Amanda Kościelna
Karolina Żydek

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