Chemists in Rijeka Together for Fifty Years

S koje god strane svijeta dođete u Rijeku, došli ste u srce Europe. Rijeka vas čeka mirisom svojega mora i gostoljubivošću svojih stanovnika. Rijeka je grad neobične i burne, čvornate prošlosti. Krajem 19. stoljeća riječko je područje bilo jedna od najsnažnije koncentriranih industrijskih zona u Europi. Ugledni kemičar prof. dr. sc. Eugen Cerkovnikov, prvi predstojnik Zavoda za kemiju i biokemiju na novoosnovanom Medicinskom fakultetu u Rijeci pokrenuo je inicijativu za osnivanje podružnice Hrvatskog kemijskog društva u Rijeci. U Velikoj predavaonici Medicinskog fakulteta u Rijeci, 18. siječnja 1958. održana je Osnivačka skupština, kojoj su nazočili mnogi ugledni znanstvenici onog vremena. Godine 1960. Hrvatsko kemijsko društvo podružnica Rijeka spaja se s Društvom kemičara i tehnologa, a 1973. i sa Sekcijom za biokemiju. Tijekom pet desetljeća postojanja ljubav prema kemiji, biokemiji, molekularnoj biologiji, tehnologiji i kemijskom inženjerstvu, ljubav prema temeljima prirodnih znanosti i želja da se odgajaju nove napredne generacije misao je vodilja Društva. Društvo ne želi biti zatvoreno u cehovsku organizaciju, već se otvoriti svima koji teže napretku. Dosadašnji predsjednici Društva bili su: Eugen Cerkovnikov (1958.-1974.), Marijan Kolombo (1974.-1980.), Josip Šilipeter (1980.-1984.), Marinko Oršić (1984.-1996.) i Nikola Blažević (1996.-). Svaki od njih na svoj je način obilježio vrijeme svoga djelovanja. Tranzicijske okolnosti zauvijek su ugasile mnoge sve do jučer iznimno moćne industrije u Rijeci. Danas Rijeka traži neke nove puteve, a mi vjerujemo da će naše Društvo i dalje djelovati.Whatever part of the World you come from, when you come to Rijeka you came to the heart of Europe. Rijeka is waiting for you with the scent of its sea and the hospitality of its people. Rijeka is a town of unusual, turbulent and intersected history. At the end of the IX Century the area of Rijeka was one of the most powerful industrial zones in Europe. Prof. Eugen Cerkovnikov, Ph. D., a much-respected chemist, first Head of the Department for Chemistry and Biochemistry on the then newly established Medical School in Rijeka, launched the initiative to form a branch-office of the Croatian Chemist Society in Rijeka. On 18 January, 1958 in the Big Classroom of the Medical School in Rijeka the Founding Assembly was held, and many respected scientists of that period were present. In 1960, the Rijeka branch-office of the Croatian Chemist Society merged with the Society of Chemists and Technologists and in 1973 the Biochemists section joined. In the five decades of its existence, the love towards chemistry, biochemistry, molecular biology, technology and chemical engineering, the love towards the basis of natural sciences and the wish to educate new, progressive generations formed the mission of the Society. The Society does not want to be closed in a guild organisation; its aim is to open its doors towards all those striving to progress. Former presidents of the Society were: Eugen Cerkovnikov (1958-1974), Marijan Kolombo (1974-1980), Josip Šilipeter (1980-1984), Marinko Oršia (1984-1996) i Nikola Bla?evia (1996-); and each one of them marked his era. Transitional circumstances have shut down forever many, until recently, extremely powerful industries in Rijeka. Today, Rijeka is searching for new paths, and we believe that our Society will continue to work on and give its contribution to this search

Chemists in Rijeka Together for Fifty Years

S koje god strane svijeta dođete u Rijeku, došli ste u srce Europe. Rijeka vas čeka mirisom svojega mora i gostoljubivošću svojih stanovnika. Rijeka je grad neobične i burne, čvornate prošlosti. Krajem 19. stoljeća riječko je područje bilo jedna od najsnažnije koncentriranih industrijskih zona u Europi. Ugledni kemičar prof. dr. sc. Eugen Cerkovnikov, prvi predstojnik Zavoda za kemiju i biokemiju na novoosnovanom Medicinskom fakultetu u Rijeci pokrenuo je inicijativu za osnivanje podružnice Hrvatskog kemijskog društva u Rijeci. U Velikoj predavaonici Medicinskog fakulteta u Rijeci, 18. siječnja 1958. održana je Osnivačka skupština, kojoj su nazočili mnogi ugledni znanstvenici onog vremena. Godine 1960. Hrvatsko kemijsko društvo podružnica Rijeka spaja se s Društvom kemičara i tehnologa, a 1973. i sa Sekcijom za biokemiju. Tijekom pet desetljeća postojanja ljubav prema kemiji, biokemiji, molekularnoj biologiji, tehnologiji i kemijskom inženjerstvu, ljubav prema temeljima prirodnih znanosti i želja da se odgajaju nove napredne generacije misao je vodilja Društva. Društvo ne želi biti zatvoreno u cehovsku organizaciju, već se otvoriti svima koji teže napretku. Dosadašnji predsjednici Društva bili su: Eugen Cerkovnikov (1958.-1974.), Marijan Kolombo (1974.-1980.), Josip Šilipeter (1980.-1984.), Marinko Oršić (1984.-1996.) i Nikola Blažević (1996.-). Svaki od njih na svoj je način obilježio vrijeme svoga djelovanja. Tranzicijske okolnosti zauvijek su ugasile mnoge sve do jučer iznimno moćne industrije u Rijeci. Danas Rijeka traži neke nove puteve, a mi vjerujemo da će naše Društvo i dalje djelovati.Whatever part of the World you come from, when you come to Rijeka you came to the heart of Europe. Rijeka is waiting for you with the scent of its sea and the hospitality of its people. Rijeka is a town of unusual, turbulent and intersected history. At the end of the IX Century the area of Rijeka was one of the most powerful industrial zones in Europe. Prof. Eugen Cerkovnikov, Ph. D., a much-respected chemist, first Head of the Department for Chemistry and Biochemistry on the then newly established Medical School in Rijeka, launched the initiative to form a branch-office of the Croatian Chemist Society in Rijeka. On 18 January, 1958 in the Big Classroom of the Medical School in Rijeka the Founding Assembly was held, and many respected scientists of that period were present. In 1960, the Rijeka branch-office of the Croatian Chemist Society merged with the Society of Chemists and Technologists and in 1973 the Biochemists section joined. In the five decades of its existence, the love towards chemistry, biochemistry, molecular biology, technology and chemical engineering, the love towards the basis of natural sciences and the wish to educate new, progressive generations formed the mission of the Society. The Society does not want to be closed in a guild organisation; its aim is to open its doors towards all those striving to progress. Former presidents of the Society were: Eugen Cerkovnikov (1958-1974), Marijan Kolombo (1974-1980), Josip Šilipeter (1980-1984), Marinko Oršia (1984-1996) i Nikola Bla?evia (1996-); and each one of them marked his era. Transitional circumstances have shut down forever many, until recently, extremely powerful industries in Rijeka. Today, Rijeka is searching for new paths, and we believe that our Society will continue to work on and give its contribution to this search

Maslinovo ulje u prevenciji bolesti srca i krvnih žila: u prirodi je spas

U ovom radu opisan je sastav maslinova ulja te njegov učinak na krvožilni sustav i bolesti krvozilnog sustava

Imidacloprid – olive orchard “guardian”

Pojava otpornosti populacije štetnika na organofosfate i metilkarbamate, inhibitore acetilkolinesteraze, dovela je do njihove slabije učinkovitosti i uvjetovala da ih neonikotinoidni insekticidi istisnu iz uporabe. Imidakloprid je najvažniji neonikotinoid, a odlikuje se niskom postojanosti u tlu, visokom insekticidnom aktivnosti i niskom toksičnosti u sisavaca. Neurofiziološke studije su potvrdile da je on agonist postsinaptičkih nikotinskih acetilkolinskih receptora, pri čemu izaziva najprije stimulaciju postsinaptičkih membrana, a nakon toga para lizu prijenosa živčanih impulsa. U Hrvatskoj se imidakloprid često koristi u maslinicima Istre i kvarnerskih otoka kao efi kasno sredstvo u zaštiti nasada maslina protiv različitih nametnika. Progresivno povećanje proizvodnje i primjene pesticida u poljoprivredi predstavlja veliku opasnost za onečišćenje okoliša, osobito podzemnih voda. Kada pesticid uđe u okoliš ovisan je o mnogim fi zikalnim i kemijskim procesima. Procesi sorpcije jedni su od glavnih faktora koji utječu na postojanost i pokretnost pesticida u okolišu. U ovome radu opisani su postupci sorpcije i razgradnje imidakloprida i njihova ovisnost o karakteristikama tla u četiri maslinika Istre i kvarnerskih otoka. Sastav i svojstva tla (veličina čestica, udio organskih tvari, kiselost tla) imaju izrazit utjecaj na postupke sorpcije i razgradnje imidakloprida. Sorpcija imidakloprida je jača, a razgradnja brža u tlu s višim udjelom gline i humusa te nižoj kiselost tla. Razgradnja imidakloprida u tlu se odvija sporo i kontinuirano. S vremenom poluraspada iznad 110 dana, imidakloprid se može svrstati u postojane pesticide. Uslijed česte primjene ipak predstavlja potencijalnu opasnost zbog ulaska u ciklus kruženja tvari u okolišu s posljedičnim štetnim djelovanjem na biljni i životinjski svijet, a time i na čovjeka.Neonicotinoids are increasingly replacing the organophosphate and methylcarbamate acetylcholinesterase inhibitors which are losing their eff ectiveness due to the selection for resistant pest populations. Imidacloprid is the most important neonicotinoid with low soil persistence, high insec cidal potency and rletively low mammalian toxicity. Neurophysiological studies have confi rmed that imidacloprid is an agonist at the postsynaptic nicotinic acetylcholine receptors which stimulates the postsynaptic membrane first and then paralyses nerve conduction. In Croatia, imidacloprid is commonly used in olive growing areas, including Istria and Kvarner islands, as an eff ective mean of olive fruit fly infestation control. Once a pesticide is introduced into the environment it can be infl uenced by many physical and chemical processes. Pesticide sorption processes are undoubtedly one of the major factors aff ecting the persistence and movement in the environment. This paper describes sorption and degradation processes of imidacloprid and investigates the relationships between soil properties and sorption and degradation characteristics in four soils, representative of northern Adriatic region, namely island Krk and a coastal Istrian region. Soil content and properties (particle size, content of organic matter, acidity) have a great eff ect on sorption of imidacloprid onto soil particle. Sorption and degradation of imidacloprid increase in soil with higher clay and organic matter content and with lower acidity. The imidacloprid degradation processes are continuous, though not very rapid. According to half-life of more than 110 days, imidacloprid is classified as persistant pesticide. However, it’s liberate usage can disturb environmental cycling and thus adversely aff ect non-target organisms, including plant and animal species. In this way, imidacloprid may also impose a risk to the human health

Uloga izomera α-, γ- i δ-tokoferola u bifaznoj kinetici uklanjanja DPPH radikala iz uzoraka bučinog ulja i uljnih mješavina

The antioxidant activity of three types of pumpkin seed oil or oil mixtures (cold-pressed, produced from roasted seed paste and salad) produced in the northern part of Croatia and the kinetics of their behaviour as free radical scavengers were investigated using DPPH˙. In addition, the involvement of oil tocopherol isomers (α-, γ- and δ-) in different steps of DPPH˙ disappearance and their impact on the rate of reaction were analysed. The kinetics of DPPH˙ disappearance is a two-step process. In the first step, rapid disappearance of DPPH˙ occurs during the first 11 min of the reaction, depending on the oil type, followed by a slower decline in the second step. To describe DPPH˙ disappearance kinetics, six mathematical models (mono- and biphasic) were tested. Our findings showed that γ- and δ-tocopherols affected DPPH˙ disappearance during the first step, and α-tocopherol in the second step of the reaction. Moreover, α-tocopherol demonstrated 30 times higher antioxidant activity than γ- and δ-tocopherols. The results indicated the biphasic double-exponential behaviour of DPPH˙ disappearance in oil samples, due to the complexity of reactions that involve different tocopherol isomers and proceed through different chemical pathways.U ovom su radu ispitani antioksidacijska aktivnost i kinetika uklanjanja DPPH radikala iz bučinih ulja ili uljnih mješavina (iz hladno-prešanog, zatim ulja dobivenog prešanjem prženih bučinih sjemenki i salatnog ulja), proizvedenih na području Sjeverne Hrvatske. Osim toga, ispitan je utjecaj različitih izomera vitamina E (α-, γ- i δ-tokoferola) na brzinu reakcije tijekom različitih stupnjeva nestanka DPPH radikala iz tih ulja. Postupak uklanjanja radikala odvija se u dva stupnja: u prvom stupnju se tijekom početnih 11 minuta reakcija odvija brzo, nakon čega slijedi sporiji, drugi stupanj. Za opisivanje kinetike nestanka radikala upotrijebljeno je šest monofaznih i bifaznih matematičkih modela. Iz dobivenih se rezultata može zaključiti da γ- i δ-izomeri tokoferola sudjeluju u prvom stupnju, dok je α-tokoferol uključen u drugi stupanj procesa uklanjanja radikala. Osim toga, utvrđeno je da α-tokoferol ima 30 puta veću antioksidacijsku aktivnost od γ- i δ-izomera. Rezultati pokazuju da je bifazna kinetika nestanka DPPH radikala posljedica niza složenih reakcija koje se odvijaju različitim mehanizmima, a u kojima sudjeluju izomeri tokoferola

Maslinovo ulje u prevenciji bolesti srca i krvnih žila: u prirodi je spas

U ovom radu opisan je sastav maslinova ulja te njegov učinak na krvožilni sustav i bolesti krvozilnog sustava

Preexposure to Olive Oil Polyphenols Extract Increases Oxidative Load and Improves Liver Mass Restoration after Hepatectomy in Mice via Stress-Sensitive Genes

Polyphenols can act as oxidants in some conditions, inducing redox-sensitive genes. We investigated the effect of preexposure to the olive oil polyphenols extract (PFE) on time-dependent changes in the hepatic oxidative state in a model of liver regeneration—a process in which oxidative stress associated with the metabolic overload accounts for the early events that contribute to the onset of liver self-repair. Liver regeneration was induced by one-third hepatectomy in mice. Prior to hepatectomy, mice were intraperitoneally given either PFE (50 mg/kg body weight) or saline for seven consecutive days, while respective controls received vehicle alone. Redox state-regulating enzymes and thiol proteins along with the mRNA levels of Nrf2 gene and its targets γ-glutamylcysteine synthetase and heme oxygenase-1 were determined at different time intervals after hepatectomy. The liver mass restoration was calculated to assess hepatic regeneration. The resulting data demonstrate the effectiveness of preexposure to PFE in stimulating liver regeneration in a model of a small tissue loss which may be ascribed to the transient increase in oxidant load during the first hours after hepatectomy and associated induction of stress response gene-profiles under the control of Nrf2