Essential oils from oregano (Origanum vulgare L.), mint (Mentha piperita L.), fennel (Foeniculum vulgare Mill.), and pine (Abies alba Mill.) needles and cones, and their active substances thymol, ...carvacrol, menthol, and anisaldehyde were tested for antifungal activity against Penicillium verrucosum. The lowest minimal inhibitory concentrations (MICs) were achieved for essential oil of oregano, followed by carvacrol, thymol, and menthol. These antifungal components were further investigated, as the main aim of our study was to elucidate the effect of natural antifungals on ochratoxin A production. During 21 days of exposure, the growth of P. verrucosum, and subsequently the production of ochratoxin A, was fully inhibited by thymol at ½ MIC (0.0625 mg mL
), but menthol at ¼ and ½ MIC (0.1875 and 3750 mg mL
) showed no growth inhibition. After 21 days of incubation, the greatest inhibitory effect on ochratoxin production (inhibition was 96.9 %) was also achieved with thymol at ¼ MIC (0.0313 mg mL
). Essential oil of oregano (¼ MIC, 0.2930 μL mL
) and carvacrol (½ MIC, 0.1953 μL mL
) stimulate production of ochratoxin A at 13.9 % to 28.8 %, respectively. The observed antifungal effects depended on the agent, the concentration used, and the time of interaction between the agent and P. verrucosum. Our results indicate the possibility of using oregano essential oil as a substitute for artificial preservatives in certain foods, but further research is needed.
Eterična olja origana (Origanum vulgare L.), mete (Mentha piperita L.), janeža (Foeniculum vulgare Mill.), in borovih (Abies alba Mill.) iglic in storžev, ter njihove sestavine timol, karvakrol, mentol in anisaldehid smo testirali kot snovi z protiglivno aktivnostjo proti plesnim vrste Penicillium verrucosum. Najnižje minimalne inhibitorne koncentracije (MICs) smo določili eteričnemu olju origana, ter karvakrolu, timolu, in mentolu. Rast plesni vrste P. verrucosum je bila popolnoma inhibirana po 21 dneh inkubacije v prisotnosti ½ MIC timola (0,0625 mg mL-1), medtem ko so eterično olje origana (½ MIC, ¼ MIC), timol (¼ MIC) in karvakrol (½ MIC, ¼ MIC) inhibirali rast plesni od 8,3 % do 70.8 %. Dodatek mentola v koncentracijah ¼ MIC in ½ MIC (0.1875 mg mL
in 0.3750 mg mL
) pa ni imel inhibitornega vpliva na rast plesni vrste P. verrucosum. Popolno inhibicijo tvorbe ohratoksina A smo določili le v primeru, ko je bila tudi rast teh plesni popolnoma inhibirana (pri ½ MIC timola). Največjo inhibicijo tvorbe ohratoksina A (96,9 %) po 21 dnevih inkubacije smo določili pri ¼ MIC timola (0.0313 mg mL
). Pospešeno tvorbo ohratoksina A (od 13,9 % do 28,8 %) pa smo določili pri ¼ MIC eteričnega olja origana (0.2930 mg mL
) in ½ MIC karvakrola (0.1953 mg mL
). Protiglivni vplivi so bili odvisni od testirane snovi, njene koncentracije ter časa interakcij med protiglivno snovjo in plesnimi vrste P. verrucosum. Rezultati nakazujejo možnosti uporabe eteričnega olja origana v živilih namesto kemijskih konzervansov. Ker pa so živila kompleksna okolja v katerih je potrebno upoštevati več dejavnikov, so potrebne nadaljnje raziskave.
Influence of some commercially available types of microcrystalline cellulose (MCC) on the stability of certain active pharmaceutical ingredients (APIs), when in contact, has been investigated. Two ...structurally similar APIs, perindopril erbumine (PER) and enalapril maleate (EM), both well-known angiotensin-converting enzyme inhibitors were used. The main properties of an MCC that could determine the stability for each API were measured and correlated to the stability of these two APIs in binary mixtures. The stability of these APIs differed when in contact with different types of MCC. The dominant properties of MCC from one manufacturer were surface features that influenced the stability of PER and acidity that influenced the stability of EM. In the case of MCC from other manufacturers, unbound water was stability determining for both substances.
V raziskavi smo proučevali vpliv nekaterih tipov komercialno dostopne mikrokristalne celuloze (MCC) na stabilnost izbranih zdravilnih učinkovin, kadar sta učinkovina in pomožna snov v stiku. Uporabili smo dve strukturno sorodni učinkovini, znana zaviralca angiotenzin-konvertaze, erbuminijev perindoprilat in enalaprilijev maleat. Izmerili smo najpomembnejše lastnosti mikrokristalne celuloze, ki bi lahko vplivale na stabilnost posamezne zdravilne učinkovine in določili povezavo med temi lastnostmi pomožne snovi in stabilnostjo zdravilnih učinkovin v binarnih zmeseh. Stabilnost obeh učinkovin se je razlikovala pri posameznih eksperimentih in je bila odvisna od tipa uporabljene mikrokristalne celuloze. Na stabilnost erbuminijevega perindoprilata so najbolj vplivale površinske značilnosti enega izmed proizvajalcev mikrokristalne celuloze, na stabilnost enalaprilijevega maleata pa njene šibko kisle lastnosti. V primeru ostalih dveh proizvajalcev mikrokristalne celuloze je na stabilnost obeh zdravilnih učinkovin najbolj vplivala nevezana voda.
The changing dynamics of organic acids, sugars, phenolics and antioxidant potential in apples from technological to edible maturity was studied. During the time of storage, the content of citric and ...malic acids generally decreased. The content of sucrose, fructose and glucose decreased significantly in some varieties, while it increased in others. The content of total sugars changed only slightly over the storage period. In the apple pulp, the content level of single phenolics generally changed to a minor extent during storage. In the peel, the content levels of the rutin and quercetin-3-rhamnoside flavonoids remained generally constant during storage, while the level of p-coumaric acid increased slightly; on the other hand, the content levels of epicatechin and catechin decreased. In the pulp of most cultivars, there was no significant decrease in total phenolics at edible maturity. In contrast, the apple peel usually has a higher content level of total phenolics at edible maturity than at the time of technological maturity. Therefore, the antioxidant activity of the peel increased from technological to edible maturity.
Proučevali smo dinamiko spreminjanja organskih kislin, sladkorjev, fenolnih spojin in antioksidativnega potenciala jabolk od tehnološke do užitne zrelosti. Vsebnost citronske in jabolčne kisline se je med skladiščenjem na splošno zmanjševala. Vsebnost saharoze, fruktoze in glukoze se je v času skladiščenja pri nekaterih sortah značilno zmanjšala, pri drugih pa povečala. Vsebnost skupnih sladkorjev se je med skladiščenjem le malo spreminjala. Na splošno se je vsebnost posameznih fenolov v pulpi jabolk v času skladiščenja le malo spreminjala. V kožici je ostala vsebnost flavonoidov rutina in kvercetin-3-ramnozida v obdobju skladiščenja približno enaka, vsebnost p-kumarne kisline se je malo povečala, medtem ko se je količina epikatehina in katehina zmanjšala. Pri večini sort je opaziti v pulpi neznačilno zmanjšanje skupnih fenolov v užitni zrelosti. Nasprotno je kožica jabolk pri večini sort v užitni zrelosti imela večjo vsebnost skupnih fenolov kot v tehnološki zrelosti. Iz tega tudi izhaja, da se je antioksidativna aktivnost kožice od tehnološke do užitne zrelosti povečala.
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