20.500.12556/RUL-99150 Ekstrakcija kofeina iz različnih naravnih virov ter njegov učinek na izbrane škodljivce Extraction of caffeine from different natural resources, and its effect on selected pests Eden od pomembnejših sekundarnih metabolitov, ki ga najdemo v kavi, čajih, guarani itn. je kofein. Kofein rastlino ščiti pred herbivori in patogenimi organizmi. Naš namen je bil preveriti kakšne vsebnosti kofeina vsebujejo različni rastlinski viri in ali bi lahko kofein uporabili kot naravno sredstvo za varstvo rastlin pred škodljivci. V našem primeru sta bila to skladiščni škodljivec koruzni žužek (Sitophilus zeamais Motschulsky) in siva breskova uš (Myzus persicae Sulzer). Iz različnih naravnih virov, kot so zeleni in črni čaj, mate čaj, ter Barcaffe kava, instant kava Nescafe in kava Deadwish smo ekstrahirali kofein in fenolne snovi. Največjo vsebnost kofeina je vsebovala instant kava Nescafe, najmanj pa mate čaj. Pri vseh pripravkih je bila največja vsebnost kofeina pri ekstrakciji z vodo, najmanjša pa pri ekstrakciji z metanolom. Vsebnosti kofeina so bile pri vseh pripravkih največje v prvi ekstrakciji. Pri preizkušanju delovanja pripravkov na izbranih škodljivcih se je izkazalo, da kljub temu, da kofein ni imel zelo velikega vpliva na smrtnost tako enih, kakor tudi drugih škodljivcev, je v manjši meri malo zaustavil njihovo razmnoževanje in nadaljnji razvoj potomcev. One of the major secondary metabolite which is found in coffee, tea, guarana, etc. is caffeine. Caffeine has an important role in the plant, because it protects the plant against herbivores and patogens. The purpose of our study was to check, what is the content of caffeine in different plant sources and whether caffeine could be used as a natural pesticide. In our case we chose corn bug (Sitophilus zeamais Motschulsky) and a green peach aphid (Myzus persicae Sulzer). From various natural resources such as green and black tea, mate tea, Barcaffe coffee, instant coffee Nescafe and Deadwish coffee we extracted caffeine and various phenolic substances. The highest caffeine content was in the instant coffee Nescafe, while the lowest content was in mate tea. For all preparations, the highest caffeine content was obtained by extraction with water, and the lowest was obtained by extraction with methanol. The content of caffeine was highest for all preparations in the first extraction. Then we tested the effects of these preparations on selected pests. Results showed that caffeine did not have a high impact on the mortality of both pests but at least it negatively influenced, their reproduction and the further development of offsprings. naravni pripravki ekstrakcija kofein fenoli črni čaj zeleni čaj mate čaj Barcaffe kava Nescafe Deadwish kava siva breskova uš Myzus persicae S. koruzni žužek Sitophilus zeamais natural preparations green tea black tea mate tea Barcaffe coffe Nescaffe Deadwish extraction caffeine phenols aphids Myzus persicae S. Sitophilus zeamais true false false [B. Gačnik] Slovenski jezik Angleški jezik Magistrsko delo/naloga 2017-12-24 07:16:13 2017-12-24 07:16:15 2022-08-16 10:32:58 0000-00-00 00:00:00 2017 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 632.951:547.857.4:632.95.024(043.2) 150664 8895353 1764.pdf 1764.pdf 1 87779ED6DD1BF05A94F052B98FA85020 2ffb64d7c921c61cfe5de105518c87f4f94b2b774b1c2fdead2d4d7ce099ee50 7de66c37-a1b4-11eb-a523-00155dcfd717 20.500.12556/rul/697d7998-741c-45b0-9d11-3db3096e447a https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=108502 Biotehniška fakulteta 0 0 0