20.500.12556/RUL-173931 Vpliv mlečnokislinske fermentacije na biorazpoložljivost železa in cinka v izbranih mokah Impact of lactic acid fermentation on iron and zinc bioaccessibility from selected flours Rastlinska živila, zlasti žita in psevdožita, so pomemben vir mineralov v človeški prehrani, vendar je njihova biorazpoložljivost, predvsem železa in cinka, pogosto omejena zaradi prisotnosti antinutritivnih snovi, kot so fitati, oksalati, polifenoli in prehranske vlaknine. Med obetavnimi biotehnološkimi pristopi za izboljšanje prehranske vrednosti izstopa mlečnokislinska fermentacija, saj mikrobni encimi lahko razgradijo minerale vezane v kompleksne spojine in s tem povečajo njihovo dostopnost za absorpcijo. V naši raziskavi smo preučili vpliv mlečnokislinske fermentacije na biorazpoložljivost železa in cinka v treh vrstah mok: pšenični, proseni in ajdovi. Substrate smo inokulirali s tremi vrstami mlečnokislinskih bakterij (Lactiplantibacillus plantarum, Levilactobacillus brevis in Limosilactobacillus fermentum). Določili smo celokupno vsebnost železa in cinka v mokah pred in po fermentaciji z metodo masne spektrometrije z induktivno sklopljeno plazmo ter jo primerjali z biorazpoložljivostjo, izmerjeno po standardizirani metodi INFOGEST. Koncentracije fitinske kisline, oksalne kisline in fosfatov smo določili z ionsko-izmenjevalno kromatografijo. Rezultati so pokazali, da fermentacija z izbranimi mlečnokislinskimi bakterijami učinkovito zmanjšuje vsebnost fitata in povečuje koncentracijo prostega fosfata, kar je lahko povezano z izboljšano biorazpoložljivostjo železa in cinka. Najizrazitejše izboljšanje smo zaznali pri proseni moki, medtem ko sta bila učinka pri pšenični in ajdovi moki manj izrazita, verjetno zaradi obdelave zrn in prisotnosti drugih antinutritivnih snovi. Sklepno lahko povzamemo, da mlečnokislinska fermentacija predstavlja učinkovit in naraven pristop za izboljšanje hranilne vrednosti rastlinskih mok, s potencialom za razvoj funkcionalnih izdelkov z večjo vsebnostjo biorazpoložljivega železa in cinka. Vendar pa kaže, da je mlečnokislinska fermentacija morda preveč odvisna od substrata, vrste bakterij in tarčnega minerala, da bi bila vsesplošna rešitev za težavo pomanjkanja železa in cinka v naši prehrani. Plant-based foods, particularly cereals and pseudocereals, are important sources of minerals in the human diet. However, their bioavailability—especially of iron and zinc—is often limited by the presence of antinutritional factors such as phytates, oxalates, polyphenols, and dietary fiber. Among the promising biotechnological approaches to improving the nutritional value of plant-based products, lactic acid fermentation stands out, as microbial enzymes can break down minerals bound in complex compounds, thereby increasing their availability for absorption. In this study, we investigated the effect of lactic acid fermentation on the bioavailability of iron and zinc in three types of flour: wheat, millet, and buckwheat. The substrates were inoculated with three species of lactic acid bacteria (Lactiplantibacillus plantarum, Levilactobacillus brevis and Limosilactobacillus fermentum). The total iron and zinc content in the flours before and after fermentation was determined using inductively coupled plasma mass spectrometry and compared with their bioavailability, measured using the standardized INFOGEST method. Concentrations of phytic acid, oxalic acid, and phosphates were determined by ion-exchange chromatography. The results showed that fermentation with the selected lactic acid bacteria effectively reduced phytate content and increased free phosphate concentration, which may be associated with improved bioavailability of iron and zinc. The most pronounced improvement was observed in millet flour, while the effects in wheat and buckwheat flours were less evident, likely due to grain processing and the presence of other antinutritional compounds. In conclusion, lactic acid fermentation represents an effective and natural approach to enhancing the nutritional value of plant-based flours, with potential for developing functional products with higher contents of bioavailable iron and zinc. However, the effects of this process appear to be highly dependent on the type of substrate, bacterial strain, and target mineral, suggesting that lactic acid fermentation may not be a universal solution to the problem of iron and zinc deficiencies in the diet. moka prehranska vrednost železo cink fitinska kislina biorazpoložljivost mlečnokislinska fermentacija flour nutritional value iron zinc phytic acid bioavailability lactic acid fermentation true false false [M. Ravnikar] Slovenski jezik Angleški jezik Magistrsko delo/naloga 2025-09-25 08:16:43 2025-09-25 08:16:48 2025-11-15 03:54:19 0000-00-00 00:00:00 2025 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 641.1:664.641:602.42:577.152.3 266212 250328835 53344.pdf 53344.pdf 1 EAFFE5693268CCA16605CC25C24BCBEE e227398bef5be3e210aa61759a7734ae43b42429cec7505529d61fa8320b00f5 07a8d546-99d7-11f0-9328-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=218635 Biotehniška fakulteta 0 0 0