A comparative investigation on physicochemical properties, chemical composition, and in vitro antioxidant activities of rice bran oils from different japonica rice (Oryza sativa L.) varieties

The main aim of this study is to evaluate and compare the physicochemical properties, chemical composition, and in vitro antioxidant activities of rice bran oil (RBO) from five most popular japonica rice ( Oryza sativa L.) varieties planted in China. It was found that the AV and PV of RBOs were 0.45–1.18 mg KOH/g and 0.72–1.73 mmol/kg, individually. The L *, a *, and b * values of RBOs were 24.18–26.70, 1.84–2.54, and 6.35–9.01, respectively. RBOs were rich in linoleic acid (38.63–43.50%), oleic acid (34.23–41.20%), and palmitic acid (16.26–18.93%). POL + SLL (17.44–19.29%), OLL (16.06–17.67%), OOL (13.79–17.79%), and PLL (11.70–14.79%) were the predominant triacylglycerols of RBOs. RBO from different rice varieties contained abundant bioactive constituents such as tocopherols and tocotrienols (948.59–1461.90 mg/kg), squalene (2055.65–4456.79 mg/kg), γ-oryzanol (19391.15–30024.09 mg/kg), phytosterols (10632.74–13948.17 mg/kg), and polyphenols (127.55–358.84 mg/kg). Pigments such as carotenoids and chlorophylls varied from 6.47 to 14.29 mg/kg and 0.79 to 12.96 mg/kg. The DPPH, ABTS, FRAP, and ORAC value were 837.41–1055.64, 1592.38–2106.47, 244.27–557.13, and 170.16–1776.41 µmol TE/100 g, respectively. This work could provide useful information to consumers for choosing suitable vegetable oils based on their health needs.