Glucosinolate profile of horseradish (Armoracia rusticana). Conventional vs. microwave assisted isolation of volatiles : bachelor thesis

Glukozinolati su sekundarni metaboliti koji se sintetiziraju iz aminokiselina. Pronađeni su u 16 porodica reda Brassicales, od kojih je najznačajnija porodica Brassicaceae (kupusnjača) u koju se ubrajaju brojne biljke svakodnevno korištene u prehrani, kao što su kupus, brokula, cvjetača i druge. Po kemijskoj strukturi glukozinolati su β- tioglukozidni-N-hidroksisulfatis varijabilnim bočnim lancem. Glukozinolati su kemijski i biološki neaktivni spojevi, a njihovom razgradnjom nastaju hlapljivi sumporovi spojevi koji imaju niz ljekovitih djelovanja. Oni se razgrađuju enzimskim, termičkim i kemijskim putem. U ovom radu primijenjene su različite metode razgradnje uključujući hidrodestilaciju u modificiranoj aparaturi po Clevengeru (100 °C, 150 min), mikrovalnu destilaciju i ekstrakciju (500 W, 98 °C, 15 - 30 min) koji su primjer termičke razgradnje te autoliza, nakon koje je uslijedila ekstrakcija s diklormetanom, koja je primjer enzimske razgradnje. Cilj rada bio je izolirati i identificirati sumporove spojeve iz hrena (Armoracia rusticana P. Gaertn., B. Mey. et Scherb.). Korijen i lišće hrena sakupljeno je u samoniklom nasadu u Konavlima (u blizini Dubrovnika, Hrvatska) u ožujku 2019. godine. Za identifikaciju spojeva korištene su GC-MS i HPLC-DAD tehnika. Analizom hlapljivih spojeva identificiran je alil-izotiocijanat, kao glavni produkt razgradnje glukozinolata koji potječe od sinigrina, zajedno s feniletil-izotiocijanatom i benzenpropanonitrilom, koji potječu od glukozinolata glukonasturcina. U listu hrena prisutan je samo sinigrin, dok je u korijenu uz sinigrin prisutan i glukonasturcin. Kasnije je potvrđeno HPLC-DAD tehnikom preko desulfatiziranih (desulfoglukozinolata) produkata.Glucosinolates are secondary metabolites that are synthesized from amino acid. They were found in 16 families of Brassicales, among the most important Brassicaceae family, which includes well-known plants of everyday nutrition such as cabbage, broccoli, cauliflower and others. Chemically these are β-thioglucoside-N-hydroxysulfates with a variable side chain. Glucosinolates are chemically and bioloyically inactice compounds, and with their degradation occur volatile sulfur compound which have a number of medicinal effects. They can be broken down by enzymatic, thermal and chemical ways. In our study we used different methods of degradation which includes hydrodistillation in a modified apparatus by Clevenger (100 °C, 150 min), microwave assisted distillation and extraction (500 W, 98 °C, 15 - 30 min), which are an example of thermal degradation, and autolysis followed by extraction with dichloromethane which is an example of enzymatic degradation. The aim of this study was to isolate and identify sulfur compounds from the horseradish (Armoracia rusticana P. Gaertn., B. Mey. et Scherb.). The roots and the leaves of horseradish were collected from the wild-growing population in Konavle (near Dubrovnik, Croatia) in March 2019. GC-MS and HPLC-DAD techniques were used to identify compounds. Analysis of the volatile compounds hasidentified the presence of allyl isothiocyanate, as the main glucosinolate degradation product originating form sinigrin, along with phenylethyl isothiocyanate and benzenpropanonitrile, originating from glucosinolate gluconasturtiin. Only sinigrin was present in the leaf of horseradish, while at the root, along with sinigrin, the presence of gluconasturtiin was also confirmed. It was later confirmed with HPLC-DAD technique acros desulfated (desulfoglucosinolates) products