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Jestivo ulje je jedno od najvažnijih prehrambenih proizvoda. Ulje se sastoji od estera alkohola glicerola i masnih kiselina te negliceridnih sastojaka. Postoje dva načina dobivanja ulja mehanički i kemijski. Mehaničkim putem dobiva se ulje bolje kvalitete ali manjih prinosa. Ovaj rad se bazira na kemijskom načinu, ekstrakciji ulja ize sjemena uljarica sa organskim otapalima. Nakon ekstrakcije potrebno je izdvojiti sirovo ulje od organskog otapala što je vrlo kompleksan proces. U industriji ulja postoje razne vrste ekstraktora koji su objašnjeni u ovom radu, a predstavljaju prekolacijski i imerzijski tip. Sirovo ulje proizvedeno postupkom ekstrakcije s organskim otapalom mora ići na proces rafinacije kako bi se dobilo jestivo biljno ulje. Edible raw oil is one of the most important food products. Oils are composed of alcohol esters of glycerol, fatty acids and non-glyceride ingredients. There are two main ways to produce oil: mechanical and chemical way. Oil produced with mechanical way has better quality and less yield. This paper deals with chemical way of oil production named extraction of oil from oil seeds with using organic solvents. After extraction, there is a need to remove raw oil from organic solvents and this process is very complex process. In edible oil industry, there are many extractors that will be explained in this paper, and they represent the percolation and immersion type of extractors. Raw oil that is produced by extraction with organic solvents has to go through the process of refining so it co could be edible.

U ovome radu ispitana je aktivnost enzima halogenhidrin-dehalogenaze u prisustvu organskih otapala različitih koncentracija. Aktivnosti enzima su praćene preko produkta p-nitrofenilstiren oksida koji je dobiven pretvorbom iz 1-(p-nitrofenil)-2-bromoetanola uz halogenhidrin-dehalogenazu kao katalizator. Proučavane su relativne aktivnosti enzima budući specifične dosta odstupaju jedna od druge. Na temelju dobivenih podataka, određena je aktivnost enzima u prisustvu pojedinog organskog otapala. Aktivnost enzima opada s porastom koncentracije organskog otapala. Porastom koncentracije organskog otapala, enzimi i dalje zadržavaju aktivnost, ali ne na razini aktivnosti u vodenom mediju. U prisustvu n-heksana, cikloheksana i toluena, enzimi zadržavaju vrlo visoku aktivnost čak i u čistom organskom otapalu. This research was focused on the activity of halohydrin dehalogenase enzyme in different concentrations of organic solvents. The assays were monitored via the p-nitrophenylstyrene oxide product obtained by conversion from 1-(p-nitrophenyl)-2-bromoethanol with halohydrin dehalogenase as catalyst. Relative activities of enzymes were evaluated and compared, since the specific ones deviate a lot from each other. Based on the obtained data, the activity of the enzyme in a particular organic solvent was determined. As concentration of organic solvent increases, enzyme activity decreases. As the concentration of the organic solvent increases, the enzymes remain active, but at lower level than in an aqueous solution. In the presence of n-hexane, cyclohexane and toluene, the enzymes retain their activity even in pure organic solvents.

S obzirom da se u procesu kemijskog čišćenja tekstila primjenjuju organska otapala, koja mogu biti toksična, zapaljiva, eksplozivna i ekološki nepovoljna, kemijske čistionice podliježu propisima za zaštitu okoliša. Zakonom je regulirana granična vrijednost izloženosti (GVI) para otapala u radnom prostoru koja nije štetna za zaposlenika tijekom punog radnog vremena. Propisani su protokoli rukovanja kemikalijama, vođenja očevidnika, mjerenja emisije i zbrinjavanja otpada. Obvezno periodičko školovanje djelatnika omogućava stjecanje znanja o štetnim učincima kemikalija na ljudski organizam, čime se smanjuje potencijalni rizik opasnosti od neželjenih posljedica i nestručnog rukovanja štetnim kemikalijama., Dry cleaning shops are subject to regulations governing environmental protection due to the extensive use of organic solvents which can be toxic, flammable, explosive and harmful to the environment. The law regulates permissible exposure limits (PEL) of solvent vapour in the area for persons exposed during full working hours. Protocols for handling chemicals, keeping the register, monitoring the emissions and waste disposal are prescribed as well. Regular periodic training enables workers to acquire the necessary knowledge of the harmful effects of chemicals on the human body, reducing potential risks of adverse consequences caused by unprofessional handling of harmful chemicals.

U ovom radu istražen je utjecaj različitih vrsta otapala ili smjese otapala puferskih otopina, organskih otapala (etanola i toluena) i detergenata na proces permeabilizacije stanične stijenke kvasca Saccharomyces cerevisiae. Istražen je utjecaj vremena na proces permeabilizacije stanične stijenke kvasca Saccharomyces cerevisiae. Uspješnost procesa permeabilizacije kvasca praćena je mjerenjem aktivnosti enzima katalaze i invertaze, te mjerenjem koncentracije proteina. Dobiveni rezultati su uspoređeni s pokusima u kojima je za proces razbijanja stanične stijenke korišten ultrazvuk. In this paper the effects of different types of solvents or solvent mixtures, buffer solution, organic solvents (ethanol and/or toluene) as well as detergents were closely examined on the permeabilization of yeast Saccharomyces cerevisiae cell wall. Also, it is examined the influence of time on Saccharomyces cerevisiae cell wall permeabilization. The efficiency of yeast permeabilization was monitored by measuring the enzyme activity of catalase and invertase and measuring the protein concentration. Those results are compared with the results of experiments od cell wall degradation by ultrasound.

Najvažniji čimbenici koje je potrebno uzeti u razmatranje okolišne održivosti tehnologije adheziva su podrijetlo ulaznih sirovina, potrošnja energije u procesu proizvodnje te utjecaj na onečišćenje okoliša.Uobičajena formulacija adheziva sadrži osnovnu polimernu komponentu koja se dobiva najčešće iz neobnovljiva izvora - nafte - i različite druge aditive te u nekim tipovima adheziva kapljeviti medij koji je organsko otapalo ili voda. Okolišna održivost tehnologije adheziva ovisi o opravdanosti izbora osnovne sirovine i aditiva, i posebno danas, sve manjeg udjela organskih otapala u formulacijama. U ovom radu predočena je analiza proizvodnje i udjela pojedinih tipova adheziva, s obzirom na polimernu komponentu u zapadnoj Europi i usporedba s proizvodnim programom malog/srednjeg proizvođača Metakema d. o. o., Ludbreg, Hrvatska. Analiza s obzirom na podrijetlo sirovina pokazala je da se najveći dio proizvodnog programa adheziva zasniva na sintetskim polimernim materijalima koji se dobivaju iz neobnovljivog izvora - nafte. Današnji pravci istraživanja bioadheziva usmjereni su na pronalaženje novih izvora polimernih materijala na osnovi prirodnih sirovina, koji mogu udovoljiti odgovarajuće zahtjeve kvalitete koja se postiže formulacijama adheziva na bazi sintetskih polimera. Vrlo važan kriterij okolišne održivosti je što manji sadržaj hlapljivih organskih spojeva u adhezivu. Provedena je analiza elemenata štetnosti pojedinih otapala koja su još uvijek dosta zastupljena u formulacijama adheziva, posebno u Hrvatskoj. U svijetu je vidljiv trend porasta udjela adheziva na bazi vode do kojeg je došlo upravo iz razloga prihvatljivosti za okoliš te obvezujućih zakonskih regulativa. Stoga se i u Hrvatskoj može očekivati sve veći porast proizvodnje održivih adheziva na bazi vode., The most important factors that influence the sustainability of the adhesive technology are the sources of raw materials, energy consumption in the production process, and impact on environmental pollution. The usual formulation of the adhesive contains base polymer component derived mostly from non-renewable sources of oil and various other additives, and in some types of adhesives the liquid media are organic solvents or water. The environmental sustainability of the adhesive technology depends on the justification of the choice of raw material and additives, and especially today, the decreasing fraction of organic solvents in the formulations. This paper presents an analysis of production and shares of certain types of adhesives, depending on the polymer component in Western Europe in comparison with the production program of Croatian small-medium manufacturer Metakem d. o. o., Ludbreg. From the comparison of the presented data for the factory Metakem and the Western European market (Fig. 1), it is evident that Metakem’s manufacturing program includes products for almost all major market segments that use adhesives. Differences in the percentage share reflects Metakem production capability, but also the demand for some types of glue on the local market. From the data presented, it is evident that adhesives have a very wide application and occupy an important position in many other industries. Hence, the sustainability of the adhesive technology is extremely important. Considering the origin of raw polymer materials in Metakem production program, as well as in the Western European market (Fig. 2), the analysis has revealed that most of the adhesives product range is based on synthetic polymeric materials obtained from non-renewable sources of oil. Thus, today’s bioadhesives research topics are focused on finding new sources of polymer materials based on natural raw materials, which can meet the appropriate quality requirements compared with those achieved by adhesive formulations based on synthetic polymers. An important criterion of environmental sustainability is the lower content of volatile organic compounds in the adhesive. Compared to the Western European market, it is evident that solvent- based adhesives are still an essential part of Metakem’s production program (Fig. 3). Based on the characteristics of the solvents used in adhesive formulations at Metakem (Table 1) it can be concluded that they are not harmful to the environment in terms of negative impact on the ozone layer or bioaccumulation. However, all the solvents in high concentrations or prolonged inhalation may seriously endanger human health, and therefore special attention is required when these solvents are used in adhesive formulations. Generally, there is an increasing trend in production of water-based adhesives in the world because of environmental acceptability and mandatory legal regulations.

Prema novijim istraživanjima izloženost organskim otapalima na radnom mjestu je mogući neovisni čimbenik rizika za razvoj nealkoholne bolesti masne jetre (NAFLD), posebno ako izloženost prelazi zakonski propisane granične vrijednosti. Kod kliničke procjene oštećenja jetre zbog izloženosti otapalima valja uzeti u obzir sinergizam prvenstveno s metaboličkim, ali i drugim čimbenicima rizika, kao što su lijekovi, alkohol, virusi, životna dob i prehrana. U uvjetima izloženosti dopuštenim koncentracijama organskih otapala NAFLD se može razviti kao bolest vezana uz rad. U izloženoj radnoj populaciji potrebna je redovita zdravstvena kontrola funkcije jetre, te pravovremen odabir posebno rizičnih osoba i njihovo isključivanje iz daljnje izloženosti otapalima kako bi se spriječila moguća trajna oštećenja., Recent epidemiological studies indicate that occupational exposure to organic solvents may be an independent risk factor for the development of nonalcoholic fatty liver disease (NAFLD), particularly if occupational exposure limits are exceeded. Clinical assessment of hepatotoxicity of industrial solvents must take into account synergism with metabolic risk factors, but also other factors like medications, alcohol, viruses, age and nutrition. If occupational exposure to solvents remains within the permissible limits NAFLD may still develop as a work-related disease. It is essential that liver function testing is included in the periodic medical assessment of solvent-exposed workers, and that high risk individuals are identified and excluded from further exposure in order to prevent the development of irreversible liver damage.

Kognitivni evocirani potencijali VEP P300 procjenjivani su u 49 tiskarskih radnika izloženih profesionalno niskim koncentracijama toluena prosječno 20 godina i u 59 kontrolnih osoba. Ispitivane skupine nisu se razlikovale po dobi, godinama radnog staža i naobrazbi. Među skupinama nije bilo razlika u navikama pijenja alkoholnih pića i pušenja cigareta, u uzimanju specifičnih lijekova (analgetika i sedativa), u broju podvrgavanja općoj anesteziji zbog operativnog zahvata, kao ni u broju ozljeda glave i vrata ili broju gubitaka svijesti. Svi ovi pokazatelji mogu utjecati na rezultate mjerenja evociranih potencijala i njihovo je procjenjivanje nužno u ispitivanju učinaka specifičnih onečišćivača kakav je toluen. Razina izloženosti toluenu procijenjena je u slučajno izabranih podskupina od 32 izložena radnika i 27 kontrolnih ispitanika. Izmjerene koncentracije toluena u perifernoj krvi i hipurne kiseline u mokraći ujutro u sredini tjedna (u srijedu) prije negoli su radnici ušli u radni prostor i koncentracije hipurne kiseline u mokraći nakon radne smjene istoga dana bile su značajno više u izloženoj skupini. Medu ispitivanim izloženim radnicima nađen je značajno veći broj onih koji su imali kognitivni val VEP P300R niže amplitude i duže latencije u usporedbi sa spontanim valom VEP P300F., Cognitive evoked potentials VEP P300 were examined in 49 workers at printing press occupationally exposed to low concentrations of toluene for averagely 20 years, and in 59 control subjects. The exposure level ot toluene was evaluated in randomly selected subgroups comprising 36 exposed and 27 control subjects. The concentrations of toluene were measured in peripheral blood on wednesday morning before entering the work area, while the hippuric acid in urine was measured before and after entering the work area. The results show that the absolute number of exposed subjects displaying lower amplitude of cognitive wave VEP P300R and prolonged latency of the accompanying spontaneous wave VEP P300F was significantly greater than that of the controls.

Organska otapala čine brojnu i heterogenu skupinu kemnijskih spojeva i smjesa, uglavnom iz reda hlapljivih ugljikovodika, široko primjenjivanu u najrazličitijim granama industrije. Dugotrajna izloženost otapalima kao mogući uzrok oštećenja središnjeg živčanog sustava, godinama je predmet epidemioloških i kliničkih istraživanja, osobito u skandinavskim zemljama, rezultati kojih su još uvijek djelomično suprotstavljeni. Danas prihvaćeni kriteriji za procjenu neurotoksičnih učinaka organskih otapala osnivaju se uglavnom na stavovima radne grupe Svjetske zdravstvene organizacije iz 1985. godine. Vrlo značajna uloga koja se pridaje neuropsibologijskim ispitivanjima te rezultati novijih istraživanja toksičnosti organskih otapala predmetom su ovog prikaza., Organic solvents comprise a large and heterogenous group of chemical compounds and mixtures, largely belonging to volatile hydrocarbons. They are widely used in various industries. Long-term exposure to orsanic solvents as a cause of the central nervous system impairment has been subject of extensive eptderniological and clinical studies for years, especially in Scandinavia, but often with inconsistent results. In 1985 the World Health Organization published the criteria for the evaluation of neurotoxic effects of solvents that are now commonly accepted. The present paper provides a short review of the current state of knowledge in the field emphasizing the role of neuropsychological methods in assessing solvent toxicity.