Antioksidativna aktivnost vodenog ekstrakta gljive Lentinus edodes obogaćene selenom

Shiitake (Lentinus edodes) belongs to medically important and delicious fungi. It is recognizable for its healing properties, excellent taste and rich aroma. According to the traditional Japanese and Chinese medicine, shiitake mushroom significantly increases the strength and vitality of the body. Shiitake contains immunostimulants, compounds that lower cholesterol, prevents clogging of blood vessels, regulates the pressure, balances blood sugar levels, regulates digestion, and improves the performance of respiratory organs by its antirheumatic and antiallergic activities. Shiitake is recommended to use as food, prevention and cure, usually in a form of a spice (dried and ground) or tea. It can be consumed fresh, too. The objective of this study was to test the effect of enrichment in selenium on antioxidant, reducing and free radical scavenging activity of water extracts from fruit body of Lentinus edodes. The fungus was enhanced by adding organic selenium, zinc (II) complex with the ligand 2.6-bis diacetylpyridine (selenosemicarbazon) and inorganic compounds (Na2SeO3) of selenium in nutritional substrate where the fungus was grown. The total selenium content in fruit body was around 50 ppm for the sample enriched with selenium originating from organic sources, and 80 ppm for the sample enriched with selenium from inorganic sources. Samples were prepared by extraction of fruiting bodies in heated water. The results indicated that water extracts of whole fruit bodies, from both control and mushrooms supplemented with selenium, had quite good antioxidant activity. However, there was no significant difference between the samples supplemented with selenium content and those that were not.Shiitake (Lentinus edodes) pripada grupi medicinski značajnih i delikatesnih gljiva. Prepoznatljiva je po svojoj lekovitosti, izvanrednom ukusu i bogatoj aromi. Prema tradicionalnoj japanskoj i kineskoj medicini, gljiva shiitake značajno povećava snagu i vitalnost organizma. Shiitake sadrže imunostimulanse, sastojke koji snižavaju holesterol, sprečavaju začepljenje krvnih sudova, regulišu pritisak, uravnotežuju nivo šećera u krvi, regulišu probavu, poboljšavaju rad disajnih organa, deluju antireumatski i antialergijski. Preporuka je da se shiitake koriste kao ukusna hrana, preventiva i lek, najčešće kao začin (sušene i mlevene) ili čaj. Mogu se konzumirati i kao sveže pripremljene. Cilj rada bio je da se razjasni da li selen dodat u supstrat za gajenje gljive Lentinus edodes utiče na redukciona svojstva ekstrakta, antioksidativnu aktivnost ekstrakta, kao i procena reaktivnosti ekstrakata prema radikalskim vrstama. Gljiva je obogaćena selenom dodavanjem organskih, Zn (II) kompleks sa ligandom 2,6-diacetilpiridin bis (selenosemicarbazon), i neorganskih jedinjenja (Na2SeO3) selena u hranljivi supstrat na kojem je gljiva uzgajana. Ukupan sadržaj selena u plodonosnom telu kretao se oko 50 ppm za uzorak obogaćen selenom iz organskog izvora i 80 ppm za uzorak obogaćen selenom iz neorganskog izvora. Uzorci su pripremljeni ekstrakcijom plodonosnih tela u zagrejanoj vodi. Dobijeni rezultati ukazuju na to da vodeni ekstrakti celih gljiva, kako kontrolnih tako i sa dodatkom selena, imaju dobru antioksidativnu aktivnost. Međutim, nije primećena značajna razlika između uzoraka sa i bez sadržaja selena

Porast i formiranje plodonosnih tela gljive Pleurotus ostreatus na supstratu obogaćenom neorganskim jedinjenjima selena

Selenium is a trace mineral chemically related to sulfur and tellurium. In the body selenium combines with protein molecules to form selenoproteins and it is distributed in low concentrations and unequally in air, soil and water all over the world. Edible mushrooms are known to be selenium accumulators. Since mushrooms contain relatively high protein levels, and they can accumulate large amounts of selenium, it is reasonable to expect that selenium could be incorporated into proteins. The growth of mycelia and fruit body formation of different medicinal mushroom strains of Pleurotus ostreatus (Hk-35 and P70) over the wide range of concentrations of inorganic form of selenium were examined. Mushrooms were cultivated on agar base media and on substrates based on sawdust. Vegetative growths of mycelium were measured as colony diameter in pure cultures supplemented with inorganic form of Se supplements, prepared as Na2SeO4 and Na2SeO3 in concentrations of: 1, 10, 25, 50, 75, 100 and 150 mg/l. Inorganic form of Se supplements, showed stimulation effects (in concentration of 1-50 mg/l) and toxic effects in higher concentration. On the standard industrial sawdust based substrate, supplemented with 100 mg/kg Na2SeO4 and Na2SeO3, accumulation of Se in fruit bodies was determined by the method of flameless atomic absorption spectrophotometer. The readings were performed on Varian SpectrAA-10 spectrophotometer equipped with VGA-76. Se as Na2SeO4 and Na2SeO3 was effectively taken up from substrates and accumulated in fruit bodies. Mushrooms accumulated selenium between 120 and 250 mg/kg dry weight. In mushrooms cultivated without Se supplement, Se contents were only about 1 mg/kg and in substrate about 0.1 mg/kg.Selen je esencijelni mikroelement, neophodan u malim količinama. Zemljište na teritoriji Evrope ima nizak sadržaj selena. Pečurke sadrže relativno visok nivo proteina, te stoga mogu da usvoje visoke koncentracije selena, koji se inkorporira u proteine formirajući selenoproteine. U radu je ispitivan uticaj većeg broja različitih koncentracija neorganskih jedinjenja selena na porast i formiranje plodonosnih tela medicinski značajne gljive Pleurotus ostreatus (komercijalni sojevi Hk-35 i R70). Porast micelijuma na sladnom agaru praćen je merenjem prečnika kolonije čiste kulture obogaćene neorganskim jedinjenjima selena. Korišćena neorganska jedinjenja selena, u obliku Na2SeO4 i Na2SeO3 (1-50 mg/l), stimulisala su porast micelijuma, dok su veće koncentracije pokazale različit toksičan efekat u zavisnosti od koncentracije dodavanog jedinjenja i soja gljive. Pečurke su zatim gajene na hranljivom supstratu obogaćenom neorganskim jedinjenjima selena koncentracije do 100 mg/kg. Sadržaj selena u plodonosnim telima određen je pomoću AAS (hidridni metod) nakon vlažne digestije i rezultati su očitani na VarianSpectarAA-10 spektrofotometru sa VGA-76 (pomoćni aparat za isparavanje) LSD testom. Analize su pokazale da su gljive upešno usvojile selen u plodonosnom telu. Totalni sadržaj selena u plodonosnom telu pečuraka zavisio je od ispitivanog soja i vrste dodavanog jedinjenja. Pleurotus ostreatus je bolje usvojila selen iz Na2SeO3 nego iz Na2SeO4. Koncentracija usvojenog selena se kretala između 120 i 250 mg/kg suve mase. U pečurkama koje su gajene na supstratu bez dodatka selena, sadržaj selena je iznosio svega oko 1 μg/g, dok se ova vrednost za čist supstrat kretala oko 0.1 mg/kg

Mechanical Properties of Composite Material Reinforced With Silica Particles Obtained from Biomass Modified With Double-Layered Hydroxides

Silica particles were produced form rice husk and used as reinforcement in the polymer matrix. The obtained silica particles' surfaces were modified with layered double hydroxides, which enabled better reinforcement in the PMMA matrix. Coprecipitation was used to synthetize Fe Al layered double hydroxides (LDH) with a Fe:Al cation content of 3:1 and an FeAl-LDH: silica ratio of 1:1. X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy with EDS were used to characterize the synthesized particles. The prepared particle amounts in the PMMA matrix were 1, 3, and 5 wt. %. The purpose of this study was to see if the obtained SiO2 particles, as well as their modification with FeAl-LDH, had any effect on the mechanical properties of polymer composite materials. The mechanical characterization of obtained composites was done using Vickers microindentation tests and impact testing. The Vickers micro-hardness test showed that the addition of reinforcement increases the hardness of the composite. When compared to the matrix, the toughness of the composite material with a higher content of particles (5 wt. %) in the energy absorbed in this impact test was three times higher.The book of abstract available at: [http://conf.univerzitetpim.com/wp-content/uploads/2022/06/Book-of-Abstracts_2022-1.pdf

Supplementary data for the article: Savić, T. D.; Ćomor, M. I.; Abazović, N. D.; Šaponjić, Z. V.; Marinović-Cincović, M. T.; Veljković, D. Ž.; Zarić, S. D.; Janković, I. A. Anatase Nanoparticles Surface Modified with Fused Ring Salicylate-Type Ligands (1-Hydroxy-2-Naphthoic Acids): A Combined DFT and Experimental Study. Journal of Alloys and Compounds 2015, 630, 226–235. https://doi.org/10.1016/j.jallcom.2015.01.041

Supplementary material for: [https://doi.org/10.1016/j.jallcom.2015.01.041]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1661

The impact of educational reform and categorization of scientific journals and scientists on physics in Serbia

The trend of the increasing participation and importance of female physicists in Serbia continues. Many women have taken leading position in research and faculty governance and are contributing significantly to educational reform and the improvement of physics education in the primary and secondary schools

Supplementary data for the article: Savić, T. D.; Ćomor, M. I.; Abazović, N. D.; Šaponjić, Z. V.; Marinović-Cincović, M. T.; Veljković, D. Ž.; Zarić, S. D.; Janković, I. A. Anatase Nanoparticles Surface Modified with Fused Ring Salicylate-Type Ligands (1-Hydroxy-2-Naphthoic Acids): A Combined DFT and Experimental Study. Journal of Alloys and Compounds 2015, 630, 226–235. https://doi.org/10.1016/j.jallcom.2015.01.041

Supplementary material for: [https://doi.org/10.1016/j.jallcom.2015.01.041]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1661

Accumulation and transformation of selenium in industrial mushrooms

Peĉurke su bogat izvor gotovo svih esencijalnih aminokiselina i vitamina, mineralnih materija, ugljenih hidrata, proteina; imaju nizak sadrņaj masti, ali vrlo visok udeo nezasićenih masnih kiselina. Gljive roda Pleurotus, imaju vrlo visoku nutritivnu vrednost, a spadaju u grupu industrijskih gljiva, lako se gaje te se na njima uspeńno moņe pratiti mogućnost akumulacije i transformacije selena. Gljive imaјu razliĉit kapacitet usvaјanja selena, ńto zavisi od vrste gljive, hranljive podloge na koјoj јe gljiva odgaјana, kao i od oblika i koncentraciјe u kom јe selen dodat u podlogu. Oĉekuje se da će gljiva usvojiti uspeńno selen iz supstrata u vidu organskih i neorganskih jedinjenja u koncentraciji koja moņe da zadovolji dnevne potrebe ĉoveka. Kako gljive sadrņe bioaktivne komponente, dodatno selenom obogaćene peĉurke moguće јe koristiti u sveņem i suńenom stanju ili kao potencijalni dijetetski suplement. Praćen je rast micelijuma razliĉitih industrijskih gljiva na sladnom agaru sa selenom dodatim u obliku neorganskih i organskih jedinjenja. Selenski kvasac i kompleks cink (selenosemikarbazon) su stimulisali rast micelije gljive bukovaĉe, dok je natrijum selenit delovao inhibitorno. Rast micelijuma gljive Ganoderma lucidum stimulisan je selenskim kvascem. Kada je u pitanju gljiva Lentinus edodes, najbolji izvor selena bio je natrijum selenit, a organska jedinjenja selena su delovala inhibitorno. Ispitivana je mogućnost akumulacije i transformacije selena iz selenita (100 mg Se/kg supstrata), selenskog kvasca (100 mg Se/kg supstrata) i kompleksnog jedninjenja (50 mg Se/kg supstrata) u plodonosno telo model gljive Pleurotus ostreatus P70. Kod ostalih ispitivanih sojeva (Pleurotus ostreatus P80, Pleurotus salmoneostramineus i Pleurotus cornucopiae), praćena je mogućnost usvajanja selena samo iz selenskog kvasca kao najpogodnijeg izvora selena. Selen iz selenita efektno je akumuliran u plodonosno telo soja P. ostreatus P70, kao i selen iz organskog kompleksnog jedinjenja...Mushrooms contain almost all essential amino acids and vitamins, minerals, carbohydrates, proteins, they have low content of fats, but they are very rich in unsaturated fatty acids. Fungi of the genus Pleurotus, have high nutritional value, they are member of industrial fungi, easy to grow and the possibility of accumulation and transformation of selenium in fruit body is easy to be monitored. Mushrooms have a different absorption capacity of selenium, which is dependent on the type of substrate for mushroom growing, on the strain of fungi as well as the form and concentration of the selenium which is added to the substrate. It is expected that selenium is going to be accumulated by fungi easy from the substrate in the form of organic or inorganic compounds in a concentration that can satisfy the daily needs of the man. As enriched fungi contain bioactive compounds with selenium, they can be used as a potential pharmaceutical supplement or as fresh or dry fruit body. Mycelium growth of various industrial fungi on malt agar with selenium in the form of inorganic and organic compounds was monitored. Selenium yeast and complex zinc (selenosemicarbazone) stimulated the growth of Oyster mushroom mycelium, and sodium selenite seemed to be toxic. Mycelium growth of the fungus G. lucidum was stimulated by selenized yeast. When it comes to mushroom L. edodes, the best source of selenium was sodium selenite, and organic selenium compounds had inhibitory action. The possibility of transformation and accumulation of selenium from sodium selenite (Se 100 mg/kg of substrate), selenium yeast (100 mg Se/kg of substrate) and complex selenosemicarbazone (50 mg Se / kg substrate) in fruit body of model mushroom P. ostreatus P70 was examined. For other tested strains (P. ostreatus P80, P. salmoneostramineus and P. cornucopiae), only the possibility of accumulation of selenium from selenized yeast as the most appropriate source of selenium was examined. Selenium in the form of sodium selenite and organic complex compound is effectively accumulated in the P. ostreatus P70 fruit body..

Accumulation and transformation of selenium in industrial mushrooms

Peĉurke su bogat izvor gotovo svih esencijalnih aminokiselina i vitamina, mineralnih materija, ugljenih hidrata, proteina; imaju nizak sadrņaj masti, ali vrlo visok udeo nezasićenih masnih kiselina. Gljive roda Pleurotus, imaju vrlo visoku nutritivnu vrednost, a spadaju u grupu industrijskih gljiva, lako se gaje te se na njima uspeńno moņe pratiti mogućnost akumulacije i transformacije selena. Gljive imaјu razliĉit kapacitet usvaјanja selena, ńto zavisi od vrste gljive, hranljive podloge na koјoj јe gljiva odgaјana, kao i od oblika i koncentraciјe u kom јe selen dodat u podlogu. Oĉekuje se da će gljiva usvojiti uspeńno selen iz supstrata u vidu organskih i neorganskih jedinjenja u koncentraciji koja moņe da zadovolji dnevne potrebe ĉoveka. Kako gljive sadrņe bioaktivne komponente, dodatno selenom obogaćene peĉurke moguće јe koristiti u sveņem i suńenom stanju ili kao potencijalni dijetetski suplement. Praćen je rast micelijuma razliĉitih industrijskih gljiva na sladnom agaru sa selenom dodatim u obliku neorganskih i organskih jedinjenja. Selenski kvasac i kompleks cink (selenosemikarbazon) su stimulisali rast micelije gljive bukovaĉe, dok je natrijum selenit delovao inhibitorno. Rast micelijuma gljive Ganoderma lucidum stimulisan je selenskim kvascem. Kada je u pitanju gljiva Lentinus edodes, najbolji izvor selena bio je natrijum selenit, a organska jedinjenja selena su delovala inhibitorno. Ispitivana je mogućnost akumulacije i transformacije selena iz selenita (100 mg Se/kg supstrata), selenskog kvasca (100 mg Se/kg supstrata) i kompleksnog jedninjenja (50 mg Se/kg supstrata) u plodonosno telo model gljive Pleurotus ostreatus P70. Kod ostalih ispitivanih sojeva (Pleurotus ostreatus P80, Pleurotus salmoneostramineus i Pleurotus cornucopiae), praćena je mogućnost usvajanja selena samo iz selenskog kvasca kao najpogodnijeg izvora selena. Selen iz selenita efektno je akumuliran u plodonosno telo soja P. ostreatus P70, kao i selen iz organskog kompleksnog jedinjenja...Mushrooms contain almost all essential amino acids and vitamins, minerals, carbohydrates, proteins, they have low content of fats, but they are very rich in unsaturated fatty acids. Fungi of the genus Pleurotus, have high nutritional value, they are member of industrial fungi, easy to grow and the possibility of accumulation and transformation of selenium in fruit body is easy to be monitored. Mushrooms have a different absorption capacity of selenium, which is dependent on the type of substrate for mushroom growing, on the strain of fungi as well as the form and concentration of the selenium which is added to the substrate. It is expected that selenium is going to be accumulated by fungi easy from the substrate in the form of organic or inorganic compounds in a concentration that can satisfy the daily needs of the man. As enriched fungi contain bioactive compounds with selenium, they can be used as a potential pharmaceutical supplement or as fresh or dry fruit body. Mycelium growth of various industrial fungi on malt agar with selenium in the form of inorganic and organic compounds was monitored. Selenium yeast and complex zinc (selenosemicarbazone) stimulated the growth of Oyster mushroom mycelium, and sodium selenite seemed to be toxic. Mycelium growth of the fungus G. lucidum was stimulated by selenized yeast. When it comes to mushroom L. edodes, the best source of selenium was sodium selenite, and organic selenium compounds had inhibitory action. The possibility of transformation and accumulation of selenium from sodium selenite (Se 100 mg/kg of substrate), selenium yeast (100 mg Se/kg of substrate) and complex selenosemicarbazone (50 mg Se / kg substrate) in fruit body of model mushroom P. ostreatus P70 was examined. For other tested strains (P. ostreatus P80, P. salmoneostramineus and P. cornucopiae), only the possibility of accumulation of selenium from selenized yeast as the most appropriate source of selenium was examined. Selenium in the form of sodium selenite and organic complex compound is effectively accumulated in the P. ostreatus P70 fruit body..

Limited polymorphism of both classes of MHC genes in four different species of the Balkan mole rat

We analyzed the restriction fragment length polymorphism of class I and class II MHC genes in DNA from 20 individuals belonging to the four different species of the complex of species of Balkan mole rats Spalax leucodon captured at four different localities in Yugoslavia. All populations were tested with four restriction enzymes and one conserved mouse probe for each of the two classes of MHC genes. The probes employed detect either limited polymorphism of class I genes or lack of polymorphic bands containing class II genes. Of the two other subterranean rodents that have been studied, four karyotype forms of the Israeli mole rat show polymorphism in both classes of MHC genes similar to the one found in all other mammals (Nižetić et al. 1985), and the Syrian hamster shows limited polymorphism of class I genes and high polymorphism of class II genes (McGuire et al. 1985). Balkan mole rats belong to a new group in this respect, different from all mammals studied so far, since they apparently show limited polymorphism of both classes of MHC genes

Staphylococcus sciuri as a part of skin, nasal and oral flora in healthy dogs

The coagulase -negative species Staphylococcus sciuri is widespread in nature and is associated with a variety of domestic and wild animals. However, the occurrence of S. sciuri in dogs has received little attention so far. In the present study, we established the prevalence of S. sciuri in a large population of healthy dogs, and characterized isolated strains. Samples from two mucous membrane sites (anterior nares and mouth), and two hair-coated sites (head and withers) were taken from 122 dogs and inoculated into STS agar, a novel selective medium that was introduced and tested in the study. In total, 116 isolates of S. sciuri were obtained from 488 specimens. S. sciuri was isolated from 56 out of 122 (46%) dogs. The occurrence of S. sciuri in the anterior nares and mouth were significantly higher than those in withers and head. No significant association of S. sciuri occurrence in dogs and factors such as sex, age, and living environment (indoor/outdoor) was found. Out of 56 dogs, which tested positive for S. sciuri, 30 (54%) would have it as a resident flora. Thus, we showed that S. sciuri was frequently present as a part of skin, nasal and oral flora in healthy dogs both as a resident and transient carriage