Latest Articles from BioRisk Latest 6 Articles from BioRisk https://biorisk.pensoft.net/ Fri, 29 Mar 2024 08:45:50 +0200 Pensoft FeedCreator https://biorisk.pensoft.net/i/logo.jpg Latest Articles from BioRisk https://biorisk.pensoft.net/ Comparative study of metal concentration determination in albumen of hen eggs originating from industrial poultry farms, backyard and free-range hens using ICP-OES technique https://biorisk.pensoft.net/article/97322/ BioRisk 20: 129-138

DOI: 10.3897/biorisk.20.97322

Authors: Plamen M. Kirov, Metody Karadjov, Hristo K. Hristov, Radostina Alexandrova

Abstract: There have been multiple types of research focusing on the relationship between feed ingredients and metal content in the egg white due to their role in human nutrition. The aim of the present study is to determine the metal concentration in hens’ eggs and, in particular, to compare the metal concentration in egg albumen originating from industrial poultry farms with that of backyard and free-range hens. All samples were collected in Romania from five separate counties and 10 different farms, over a period of two weeks and, as a result, a total of 50 were collected, 10 from each housing system (batteries/cages, litter/soil, free-range, organic and backyard). The measurements of the metals were taken by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES), with a wide range of elements reported. For the essential elements, we measured Cr, Cu, Fe, Mn and Zn; Al, Cd, Ni and Pb for the heavy metals and, in addition, we measured B, Ba, Sr, Ca and Mg. The present study revealed that the metals in eggs from free-range hens are richer in essential elements with mean concentrations as follows: 1.528 mg/kg for Fe, 3.278 mg/kg for Zn, 0.058 mg/kg for Mn and 1.362 mg/kg for Cu. We concluded that the egg quality is closely connected with the housing system and nutrition. Furthermore, the results demonstrate that eggs from backyard housing are no better than those from free-range hens in terms of essential metal composition. The heavy and non-essential metal contents, present in the albumen of all the examined eggs, were much lower than the maximum allowed concentration and, therefore, egg consumption does not pose any risk to human health.

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Research Article Mon, 15 May 2023 20:00:10 +0300
Evaluation of abundance of microplastics in the Bulgarian coastal waters https://biorisk.pensoft.net/article/97555/ BioRisk 20: 59-69

DOI: 10.3897/biorisk.20.97555

Authors: Stanislava K. Georgieva, Zlatina V. Peteva, Mona D. Stancheva

Abstract: Plastic pollution in seawaters is ubiquitous, but quantitative estimates on the floating microplastics in the Black Sea are still limited. Plastics may adsorb persistent environmental contaminants, thus representing a potential risk for marine organisms. Aim: Thе aim of the study was evaluation of the presence and characteristics of microplastic particles (MPs) in waters from the Black Sea coast of Bulgaria. Materials and methods: Samples of coastal waters were collected from March 2021 to April 2022 from different stations on the Black Sea coast, including protected, aquaculture and industrial areas. In order to determine the number of plastic particles, 23 samples were collected from the surface waters at depth of 1–3 m close to the Bulgarian shore. Samples were treated with H2O2, plastic particles were isolated by density separation and filtered over a membrane filter. Identification analysis of micro particles (< 5 mm) was performed visually by microscopy. Main results: Results indicated widespread presence of microplastics in coastal waters. Mean MPs concentration was calculated 7.3 ± 4.9 pt/l. The comparison of the North, Varna and South sampling area showed that there is no significant difference in the abundance of plastic particles. The most dominant type forms were fibres followed by fragments. The most abundant size class of fragments was 101–500 μm Ferret diameter. Conclusion: Further studies are needed in order to fill knowledge gap and to evaluate distribution of plastic particles in the Black Sea and their potential ecological risk.

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Research Article Mon, 15 May 2023 20:00:05 +0300
Potential risk resulting from the influence of static magnetic field upon living organisms. Numerically simulated effects of the static magnetic field upon simple alkanols https://biorisk.pensoft.net/article/76997/ BioRisk 18: 35-55

DOI: 10.3897/biorisk.18.76997

Authors: Wojciech Ciesielski, Tomasz Girek, Zdzisław Oszczęda, Jacek A. Soroka, Piotr Tomasik

Abstract: Background: Recognising effects of static magnetic field (SMF) of varying flux density on flora and fauna is attempted. For this purpose, the influence of static magnetic field upon molecules of lower alkanols i.e. methanol, ethanol, propan-1-ol, propan-2-ol, butan-1-ol, S-butan-2-ol, isobutanol and tert-butanol is studied. Methods: Computations of the effect of real SMF 0.0, 0.1, 1, 10 and 100 AFU (Arbitrary Field Unit; here 1AFU > 1000 T) flux density were performed in silico (computer vacuum), involving advanced computational methods. Results: SMF polarises molecules depending on applied flux density, but it neither ionises nor breaks valence bonds. Some irregularities in the changes of positive and negative charge densities and bond lengths provide evidence that molecules slightly change their initially fixed positions with respect to the force lines of the magnetic field. Length of some bonds and bond angles change with an increase in the applied flux density, providing, in some cases, polar interactions between atoms through space. Conclusions: Since SMF produced and increase in the negative charge density at the oxygen atom of the hydroxyl group and elongated the –O-H bond length, these results show that SMF facilitates metabolism of the alkanols.

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Research Article Mon, 6 Jun 2022 14:23:41 +0300
Potential risk resulting from the influence of static magnetic field upon living organisms. Numerically-simulated effects of the static magnetic field upon carbohydrates https://biorisk.pensoft.net/article/77001/ BioRisk 18: 57-91

DOI: 10.3897/biorisk.18.77001

Authors: Wojciech Ciesielski, Tomasz Girek, Henryk Kołoczek, Zdzisław Oszczęda, Jacek A. Soroka, Piotr Tomasik

Abstract: Background: Recognising effects of static magnetic field (SMF) of varying flux density on flora and fauna is attempted. For this purpose, the influence of SMF upon molecules of α- and β-D-glucose, α- and β-D-galactose, α- and β-fructopyranoses, α- and β-fructofuranoses and α- and β-D-xylofuranoses and α and β-D-xylopyranoses is studied. Methods: Computations of the effect of static magnetic field (SMF) of 0.0, 0.1, 1, 10 and 100 AFU (1 AFU > 1000 T) flux density were performed in silico for SMF changes distribution of the electron density in these molecules. Hyper-Chem 8.0 software was used together with the AM1 method for optimisation of the conformation of the molecules of monosaccharides under study. Then polarisability, charge distribution, potential and dipole moment for molecules placed in SMF were calculated involving DFT 3-21G method. Results: Application of SMF induced polarisability of electrons, atoms and dipoles, the latter resulting in eventual re-orientation of the molecules along the applied field of the molecules and the electron density redistribution at particular atoms. Increase in the field strength generated mostly irregular changes of the electron densities at particular atoms of the molecules as well as polarisabilities. Energy of these molecules and their dipole moments also varied with the SMF flux density applied. Conclusions: Saccharides present in the living organisms may participate in the response of the living organisms to SMF affecting metabolism of the molecules in the body fluids by fitting molecules to the enzymes. Structural changes of saccharide components of the cell membranes can influence the membrane permeability.

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Research Article Mon, 6 Jun 2022 14:23:21 +0300
Pteromalid fauna (Hymenoptera, Pteromalidae) in oilseed rape (Brassica napus L.) fields in Bulgaria – species composition and perspectives for biological control https://biorisk.pensoft.net/article/77454/ BioRisk 17: 329-342

DOI: 10.3897/biorisk.17.77454

Authors: Ivaylo Todorov, Toshko Ljubomirov, Vlada Peneva

Abstract: Parasitoid wasps belonging to the family Pteromalidae are widespread and abundant members of the insect communities in the temperate regions of the world. As many other chalcids do, pteromalids serve as natural enemies of the pests in various crops and play an important role in the biological control of these harmful insects. Here we present the results of a field study in Bulgaria which was focused on the diversity of family Pteromalidae in ten oilseed rape fields. All samples were collected by sweep netting on the border line or inside the crop field. A total of 93 pteromalid specimens belonging to 26 taxa were gathered. The most abundant genus was Mesopolobus – 67% of the sampled pteromalids. The most numerous species in the samples was Mesopolobus morys – a well-known key parasitoid of the cabbage seed weevil, Ceutorhynchus obstrictus, in Europe. One species – Halticoptera patellana, is recorded for the first time in Bulgarian fauna. Clearfield oilseed rape fields had relatively higher parasitoid abundance and richness than the fields treated by conventional technology. In the present work we discuss the overall species composition of Pteromalidae obtained from the studied areas and present our point of view on the perspectives for biological control of oilseed rape pests.

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Research Article Thu, 21 Apr 2022 19:00:30 +0300
Expansion of Crocothemis erythraea in Ukraine https://biorisk.pensoft.net/article/1884/ BioRisk 5: 211-223

DOI: 10.3897/biorisk.5.851

Authors: Lyudmyla Khrokalo

Abstract: A noticeable expansion of some Mediterranean species takes place in Europe during last several decades and this data are related to climatic effects clearly. The present work is a review of literature and original data on distribution of C. erythraea in Ukraine. In the beginning and middle of XX century in Ukraine the Scarlet Dragonfly was observed in southern area at Dnieper valley, in outmost southwest at Danube delta at the west of Ukraine in Transcarpathian and Forecarpathian. Next, this species was registered at the foothills of Carpathian Mountains. During last three decades C. erythraea was also recorded at the north and east (central regions, eastern, northern and northeastern areas). Since 2000 new points have been registered in Odessa, Kherson,Vinnytsya, Cherkasy, Chernihiv, Kyiv administrative regions and in Crimea.

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Research Article Thu, 30 Dec 2010 00:00:00 +0200