Physico-chemical Parameters and Antioxidant Activity of Romanian Sea Buckthorn Berries

Abstract

Physico-chemical parameters of Romanian sea buckthorn fresh or dried berries, including titratable acidity (2.28±0.06 g malic acid/100 g FM), pH (2.60±0.08), contents of moisture (75.94±2.14 g/100 g FM), ash (2.83±0.11 g/100 g DM), ascorbic acid (1337.6±37.2 mg/100 g FM), oil (3.82±0.16 g/100 g FM), and macro elements, mainly K (11654 mg/kg DM), Mg (668 mg/kg DM), Ca (645 mg/kg DM), Na (401 mg/kg DM), and P (271 mg/kg DM), were evaluated in this paper. The most abundant volatile compounds found in the volatile fraction of berries were isopentyl isovalerate (30.8%), heptanal (11.7%), ethyl hexanoate (10.5%), ethyl isovalerate (8.1%), hexanal (7.5%), and ethyl 2-methylbutyrate (6.3%). Total phenolic content, total flavonoids content, and antioxidant activity (expressed as DPPH free radical scavenging activity by inhibition of DPPH) of extract solutions obtained from dried berries by MAE using ethanol/water mixture as a solvent were estimated at different ratios of solvent volume/vegetal material mass (15-30 mL/g) and ethanol/water (50/50, 60/40, 70/30, and 80/20 v/v). Inhibition of DPPH (22.61-48.60%) was well correlated with total phenolic content (4.42-10.04 mg caffeic acid equivalents/g DM) and total flavonoids content (5.37-11.14 mg quercetin equivalents/g DM). Keywords: Sea buckthorn, ascorbic acid, titratable acidity, oil, volatiles, minerals, total phenols, total flavonoids, antioxidant activity