22 research outputs found
Primjena kulture stanica prednjeg režnja hipofize u toksikoloŔkim istraživanjima
High density plating procedure was used to evaluate the effect of atrazine on anterior pituitary cells of rats in monolayer culture. Collagenase-dispersed pituitary cells plated in suspension with medium-199 and 10% foetal calf serum attached quantitatively to plastic surfaces within 24 hours. Electron microscopy showed subpopulations of different cell types. After prolonged cultivation, most cells established small colonies with extensive contacts among them. Cell-to-cell formation of aggregates was significant and the colonies manifested morphological changes. The cells retained their enzymatic activity, converting testosterone into 5alfa-dihydrotestosterone by enzyme 5alfa-reductase. Immunohistochemical techniques facilitated differentiation of gonadotrophs producing follicle stimulating (FSH) and luteinising hormones (LH). Atrazine in concentrations of 5 to 50 Āµg/ml of medium was associated with a significant reduction in the number of viable cells within 72 hours. The results suggest that the pituitary cell culture may prove useful in toxicological testing of various toxic compounds and reduce or replace in vivo animal experiments.Atrazin, selektivni s-triazinski herbicid, danas se rabi u velikim koliÄinama za zaÅ”titu kukuruznih polja, a zbog svoje liposolubilnosti i perzistentnosti u okoliÅ”u ulazi u hranidbeni lanac. In vitro sustavi tkiva i organa sisavaca uz in vivo pokuse joÅ” i danas su pretežite tehnike u toksikologiji koje se pouzdano primjenjuju. Potrebe za smanjenjem broja pokusa na životinjama dovele su do intenzivna razvoja tehnika sa životinjskim stanicama, bilo da se radi o primarnim kulturama ili o staniÄnim linijama. Primarne kulture stanica srediÅ”njega živÄanog sustava nisu do danas doživjele punu primjenu. Primjena životinjskih stanica mnogo je jeftinija tehnika koja omoguÄuje provoÄenje istodobnog ispitivanja na velikom broju uzoraka.
Cilj istraživanja bio je ispitati toksiÄnost atrazina u in vitro uvjetima na modelu kulture stanica hipofize, koje su odgovorne za normalno funkcioniranje reprodukcijskog procesa. U radu se dobrom izolacijskom metodom i visokim stupnjem uspjeÅ”nog uspostavljanja kulture stanica, mogao pratiti utjecaj atrazina na razini staniÄnih promjena. Stanice rasprÅ”ene kolagenazom u suspenziji s medijem 199 i 10%-tnim teleÄim serumom prihvatile su se za plastiÄnu podlogu unutar 24 sata. Elektronskom mikroskopijom naÄeni su razliÄiti tipovi stanica. Nakon produljene kultivacije, najveÄi broj stanica stvorio je male kolonije s uoÄljivim vezama izmeÄu stanica. Stanice su pokazale dobru enzimsku aktivnost pri pretvorbi testosterona u aktivni metabolit 5alfa-dihidrotestosteron. Imunohistokemijskim metodama utvrÄene su stanice koje sintetiziraju hormone Å”to stimuliraju razvoj folikula (FSH) i hormone luteinizacije (LH). Atrazin je dodan kulturi stanica hipofize u koncentracijama 5ā50 Āµg/ml medija koji je sadržavao 3x105 stanica. Tijekom 24, 48 i 72 sata naÄena su znaÄajna smanjenja broja živih stanica, od 36 do 46%. UÄinci su ovisili o dozi atrazina. Rezultati upuÄuju na to da se kulture stanica adenohipofize mogu uspjeÅ”no rabiti u buduÄim istraživanjima toksiÄnosti razliÄitih tvari radi smanjenja ili zamjene in vivo pokusa na životinjama
Potential Application of Yeast Ī²-Glucans in Food Industry
Different Ī²-glucans are found in a variety of natural sources such as bacteria, yeast, algae, mushrooms, barley and oat. They have potential use in medicine and pharmacy, food, cosmetic and chemical industries, in veterinary medicine and feed production. The use of different Ī²-glucans in food industry and their main characteristics important for food production are described in this paper.
This review focuses on beneficial properties and application of Ī²-glucans isolated from different yeasts, especially those that are considered as waste from brewing industry. Spent brewerās yeast, a by-product of beer production, could be used as a raw-material for isolation of Ī²-glucan. In spite of the fact that large quantities of brewerās yeast are used as a feedstuff , certain quantities are still treated as a liquid waste. Ī²-Glucan is one of the compounds that can achieve a greater commercial value than the brewerās yeast itself and maximize the total profitability of the brewing process. Ī²-Glucan isolated from spent brewerās yeast possesses properties that are benefi cial for food production. Therefore, the use of spent brewerās yeast for isolation of Ī²-glucan intended for food industry would represent a payable technological and economical choice for breweries
ESEM Comparative Studies of Hop (Humulus lupulus L.) Peltate and Bulbous Glandular Trichomes Structure
Hop glandular trichomes are developing on the epidermis of hop cones bracts. The anticline cross cut of hop peltate glandular trichomes in Environment Scanning Electron Microscopy (ESEM) observations confirmed spheroid shape of cells. In our research, length of internal peltate glandular trichomes cells varied from 16.00 to 21.47 Ī¼m, width from 4.21 to 4.70 Ī¼m and volume from 1.19 Ć 10-6 to 1.99 Ć 10-6 mm3. The diameter of cell walls varied from 2.11 to 2.94 Ī¼m. Volume of observed peltate glandular trichomes varied from 1.65 Ć 10-2 to 1.95 Ć 10-2 mm3. The cell structure of bulbous glandular trichomes in anticline cross cut was not observed. According to 121 observations, bulbs formation was visible on the surface of peltate glandular trichomes in the last phase of morphogenesis. Biosynthesis of hop secondary metabolites and activation of their genetic mechanisms are the most intensive at the end of technological maturity of hop cones of hop cultivar Aurora. It is possible that bulbous glandular trichomes represent the final stage of peltate glandular trichome morphogenesis, instead of being separate morphological formations. During biosynthesis of hops secondary metabolites partial pressures of liquids and gasses increase causing breakage of cell walls, which withdraw towards tunica and form papillary texture
Application of Different Drying Methods on Ī²-Glucan Isolated from Spent Brewerās Yeast Using Alkaline Procedure
Water-insoluble (particulate) Ī²-glucan was isolated from the cell walls of spent brewerās yeast using a single-step alkaline treatment. To stabilize Ī²-glucan water suspensions, sonication was successfully applied. Three different drying methods were used: air-drying, lyophilization and spray-drying. Air-drying and lyophilization caused Ī²-glucan particles agglomeration and changes of their microstructure. Sonication combined with spray-drying resulted in minimal Ī²-glucan structural changes and negligible formation of agglomerates. Reaggregation of spray-dried Ī²-glucan particles was minimal even after resuspending in water
Karakterizacija Ī²-glukana izoliranih iz pivskoga kvasca te osuÅ”enih razliÄitim metodama
Two different procedures have been used for isolation of water-insoluble Ć-glucans from brewerās yeast: alkaline-acidic isolation (AA) and alkaline-acidic isolation with mannoprotein removal (AAM). The obtained Ć-glucans were then dried by air-drying, lyophilization and combination of sonication and spray-drying. Ć-Glucan preparations obtained by AA and AAM isolations had similar values of dry mass, total polysaccharides, proteins and organic elemental microanalysis. The mass fractions of Ć-glucan in total polysaccharides were significantly affected by different isolation procedures. Fourier transform infrared (FTIR) spectra of all preparations had the appearance typical for (1ā3)-Ć-D-glucan. Lyophilization and especially air-drying caused a higher degree of agglomeration and changes in Ć-glucan microstructure. Sonication followed by spray-drying resulted in minimal structural changes and negligible formation of agglomerates.Netopljivi Ī²-glukani izolirani su iz pivskoga kvasca primjenom dvaju razliÄitih postupaka: alkalno-kiselinskog (AK) i alkalno-kiselinskog s uklanjanjem manoproteina (AKM). Dobiveni pripravci Ī²-glukana osuÅ”eni su na zraku, liofilizacijom i rasprÅ”ivanjem uz prethodnu obradu ultrazvukom. Takvi su pripravci, dobiveni AK i AKM postupcima, imali približno iste vrijednosti suhe tvari, ukupnih polisaharida i proteina, te udjele ugljika, duÅ”ika i kisika odreÄene organskom mikroanalizom. Na udio Ī²-glukana u ukupnim polisaharidima bitno su utjecali razliÄiti postupci izolacije. FT-IR spektri svih pripravaka imali su izgled tipiÄan za (1ā3)-Ī²-D-glukan. SuÅ”enjem na zraku i liofilizacijom doÅ”lo je do znaÄajnih promjena strukture Äestica i aglomeracije Ć-glukana. SuÅ”enje rasprÅ”ivanjem uz prethodnu obradu ultrazvukom nije dovelo do stvaranja nakupina Äestica kao ni do znatnih promjena njihove strukture
Karakterizacija Ī²-glukana izoliranih iz pivskoga kvasca te osuÅ”enih razliÄitim metodama
Two different procedures have been used for isolation of water-insoluble Ć-glucans from brewerās yeast: alkaline-acidic isolation (AA) and alkaline-acidic isolation with mannoprotein removal (AAM). The obtained Ć-glucans were then dried by air-drying, lyophilization and combination of sonication and spray-drying. Ć-Glucan preparations obtained by AA and AAM isolations had similar values of dry mass, total polysaccharides, proteins and organic elemental microanalysis. The mass fractions of Ć-glucan in total polysaccharides were significantly affected by different isolation procedures. Fourier transform infrared (FTIR) spectra of all preparations had the appearance typical for (1ā3)-Ć-D-glucan. Lyophilization and especially air-drying caused a higher degree of agglomeration and changes in Ć-glucan microstructure. Sonication followed by spray-drying resulted in minimal structural changes and negligible formation of agglomerates.Netopljivi Ī²-glukani izolirani su iz pivskoga kvasca primjenom dvaju razliÄitih postupaka: alkalno-kiselinskog (AK) i alkalno-kiselinskog s uklanjanjem manoproteina (AKM). Dobiveni pripravci Ī²-glukana osuÅ”eni su na zraku, liofilizacijom i rasprÅ”ivanjem uz prethodnu obradu ultrazvukom. Takvi su pripravci, dobiveni AK i AKM postupcima, imali približno iste vrijednosti suhe tvari, ukupnih polisaharida i proteina, te udjele ugljika, duÅ”ika i kisika odreÄene organskom mikroanalizom. Na udio Ī²-glukana u ukupnim polisaharidima bitno su utjecali razliÄiti postupci izolacije. FT-IR spektri svih pripravaka imali su izgled tipiÄan za (1ā3)-Ī²-D-glukan. SuÅ”enjem na zraku i liofilizacijom doÅ”lo je do znaÄajnih promjena strukture Äestica i aglomeracije Ć-glukana. SuÅ”enje rasprÅ”ivanjem uz prethodnu obradu ultrazvukom nije dovelo do stvaranja nakupina Äestica kao ni do znatnih promjena njihove strukture
Application of Different Drying Methods on Ī²-Glucan Isolated from Spent Brewerās Yeast Using Alkaline Procedure
Water-insoluble (particulate) Ī²-glucan was isolated from the cell walls of spent brewerās yeast using a single-step alkaline treatment. To stabilize Ī²-glucan water suspensions, sonication was successfully applied. Three different drying methods were used: air-drying, lyophilization and spray-drying. Air-drying and lyophilization caused Ī²-glucan particles agglomeration and changes of their microstructure. Sonication combined with spray-drying resulted in minimal Ī²-glucan structural changes and negligible formation of agglomerates. Reaggregation of spray-dried Ī²-glucan particles was minimal even after resuspending in water
Physico-chemical analysis of the Rhine Riesling wines produced in PleÅ”ivica-OkiÄ wine region during three consecutive years
Analizirani uzorci vina sorte Rajnski rizling iz vinogorja PleÅ”ivica-OkiÄ proizvedeni su tijekom tri uzastopne godine (2009., 2010. i 2011.) na jednom obiteljskom gospodarstvu. Koncentracije alkohola, ukupnih i hlapljivih kiselina, ukupnog SO2 , glicerola i reducirajuÄih Å”eÄera u analiziranim vinima u skladu su sa zakonskim propisima. UoÄen je izražen utjecaj klimatskih uvjeta na kemijski sastav analiziranih vina.The analyzed samples of Rhine Riesling wine from the PleÅ”ivica-OkiÄ wine region were produced during three consecutive years (2009, 2010 and 2011) in one family winery. Concentrations of alcohol, total and volatile acidity, total SO2 , glycerol and residual sugar in the analyzed wines were in accordance with legal requirements. A pronounced influence of climatic conditions on the chemical composition of the analyzed wines was observed
Importance of Medical Effects of Xanthohumol, Hop (Humulus lupulus L.) Bioflavonoid in Restructuring of World Hop Industry
Nowadays, the world hop industry is faced with one of the biggest crisis in the history. Permanent decrease of hopping rates in the world beer industry during last 20 years caused many problems to hop producers all around the world. It resulted in the huge surpluses of hop stocks between years 2008 and 2010, the ages known as āyears of famineā for hop farmers. The hop contains some compounds having medical, pharmaceutical or biological activities, and xanthohumol is one of them. Xanthohumol is a bioflavonoid whose positive effect is confirmed both in vitro and in vivo experiments. It is successfully used in medical treatment of patients having diseases such as prostate and breasts cancer, osteoporosis, menopausal problems, and even HIV. However, such attributes of hop are strong argument to consider the restructuring of the world hop industry and forming a new supply chain, primarily oriented to the pharmaceutical industry
Odabrani biotehnoloÅ”ki Äimbenici koji utjeÄu na alkoholnu fermentaciju pri proizvodnji vina
Odstupanja od normalnog tijeka fermentacije predstavljaju veliki problem u proizvodnji vina. Važno je poznavati Äimbenike koji utjeÄu na tijek fermentacije kako bi se izbjeglo usporavanje i/ili zastoj fermentacije te sprijeÄilo ekonomske gubitke. Brojna istraživanja pokazala su da odstupanja od normalnog tijeka fermentacije mogu imati viÅ”e uzroka. U ovom radu su ukratko objaÅ”njeni najvažniji Äimbenici koji utjeÄu na tijek fermentacije u proizvodnji vina, a mogu se grupirati u tri skupine - nedostatak nutrijenata, prisutnost spojeva koji inhibiraju alkoholnu fermentaciju te utjecaj enoloÅ”kih postupaka. Pored zasebnih uÄinaka pojedinih Äimbenika, moguÄe je i smanjenje brzine fermentacije zbog njihovog sinergistiÄkog djelovanja, Å”to fermentacijske probleme Äini joÅ” složenijima