Antioxidant Content Of Four Leafy Vegetables From Montenegro

Ljubica IVANOVIC, Centre of Excellence in Bioinformatics , BIO-ICT , Montenegro
MILASEVIC I. 1 , DJUROVIC D. 1 , TOPALOVIC A. 2 , KNEZEVIC M. 2 , MUGOSA B. 1

1 Institute of Public Health of Montenegro, Center of excellence in bioinformatics , Podgorica, Montenegro
2 Biotechnical Faculty, Center of excellence in bioinformatics , Podgorica, Montenegro

It has been suggested that daily intakeof leafy vegetables have a positive effect in preventions of chronic human disease such as cancer,due to the presence of antioxidants. Antioxidant compounds,phenolic compounds, flavonoids and some minerals (Cu, Fe, Zn and Mn) have been reported as chemicals that contribute to the antioxidant potential. The aim of this paper was to determine the antioxidant potential of selected leafy vegetables from Montenegro (swiss chard, spinach, collard green and parsley), measuring total phenol and flavonoid content as well as mineral (Fe, Zn, Cu and Mn).
The leaves of selected vegetables wereair-dry at room temperature and grounded to fine powder. Dried samples were extracted with boiling water and every sample was analyzed for total phenol and flavonoid content by the Folin-Ciocalteau and colorimetric aluminium chloride methods respectively using spectrophotometric technique.Total concentration of Cu, Zn, Fe and Mn was prepared using microwave digestion (ETHOS1) with HNO3 and H2O2 and measured by ICP-OES instrument.
Total phenolic content of extracts ranged from 227,2mg of galic acid equivalent (GAE) /g of dry sample (parsley) to 432,7mg (GAE)/g of dry sample (spinach). Flavonoid content is highly positively correlated with phenolic content(R2=0,998448) and consequently the highest value was in spinach 135 mg of quercetin equivalent/g of dry samples and the lowest in parsley 43,52mg of QE/g of dry samples. All analyzed minerals showed the highest value in spinach (Zn=104,7mg/kg of dry samples, Cu=137mg/kg, Mn= 130,7mg/kg and Fe=154,2mg/kg) and the lowest in parsley (Zn=28,55mg/kg of dry samples, Cu=15,97mg/kg, Mn= 49,75mg/kg and Fe=74,5mg/kg).
The tested vegetablesshowedthe high phenolic, flavonoid and mineral content and should be included in daily consumption for diseases prevention.
This work has been supported by the Ministry of Science of Montenegro and the HERIC project through the BIO-ICT Centre of Excellence (Contract No. 01-1001).