Oxalate Content in Fruits of Different Elderberry Genotypes

Bezgi predstavljajo zelo razširjeno skupino rastlinskih vrst. V Evropi je najbolj znan in razširjen črni bezeg (Sambucus nigra L.). Jagode tega bezga uporabljajo v proizvodnji želejev, marmelad, sirupov, sladoledov in različnih pijač. Plodovi namreč vsebujejo veliko koristnih snovi kot so različni sladkorji, organske kisline, vitamini, minerali in polifenoli. Bezgove jagode vsebujejo tudi antinutriente, ki so v človekovi prehrani v prevelikih količinah nezaželeni in škodljivi za zdravje. Med antinutriente spadajo tudi oksalati. Namen diplomske naloge je bil določiti vsebnost celokupnih in vodotopnih oksalatov v jagodah različnih medvrstnih križancev bezga, ki so bile pobrane v različnih stopnjah zrelosti. Celokupne oksalate smo ekstrahirali z 2M HCL, za ekstrakcijo vodotopnih pa smo uporabili vodo. Koncentracije oksalatov smo izmerili s tekočinsko kromatografijo visoke ločljivosti (HPLC) povezano s PDA detektorjem. Najvišjo vsebnost vodotopnih oksalatov (61,7 mg/100 g suhe snovi) smo izmerili pri medvrstnem križancu ((JA × NI) × MIQ) × (CER × NI)), najnižjo pa pri JA×NI (16,3 mg/100 g suhe snovi). Rezultati so pokazali statistično značilne razlike v vsebnosti celokupnih, vodotopnih in netopnih oksalatov med zelenimi in zrelimi jagodami.Elderberries represent a widespread group of plant species in most parts of the world. In Europe, the best known is black elder or black elderberry (Sambucus nigra L.). Elderberries are used in the production of jellies, marmalades, syrups and various beverages. The fruits contain many beneficial substances, such as various sugars, organic acids, vitamins, minerals and polyphenols. Elderberries also contain certain amounts of antinutrients that are undesirable in human diet and can be harmful in excessive quantities. Among such substances are oxalates. The purpose of the presented study was to determine the content of total and soluble oxalates in fruits of various interspecific elderberry hybrids at different stages of maturity. The total oxalates were extracted with 2M HCL, whereas water was used for the extraction of soluble oxalates. The oxalate concentrations were measured by high performance liquid chromatography (HPLC) combined with a PDA detector. The highest content of soluble oxalates (61.7 mg/100 g of dry weight) were determined in interspecific hybrid ((JA × NI) × MIQ) × (CER × NI), while the lowest (16.3 mg/100 g of dry weight) in JA × NI. There were significant differences in the contents of total, soluble and insoluble oxalates in certain stages of maturity