Trophotometrically at 450 nm. Inside the presence of an enzymatic antioxidant, the reduction of WST-1 could be inhibited by neutralizing O- . Hence, the SOD activity may be quanti2 fied by measuring the decrease inside the color development at 450 nm. The outcomes in Table 4 show that the ethyl acetate fraction exhibited the highest superoxide anion scavenging ability with inhibition rate of 51.74 ?four.9 amongst all extracts and fractions. This can be followed by hexane fraction (32.21 ?6.five ), methanol extract (29.32 ?four.5 ) and water fraction (18.06 ?four.six ). In summary, the crude and fractionated extracts of rhizomes of Alpinia pahangensis showed varying antioxidant properties inside the whole in vitro antioxidant assays. The ethyl acetate fraction showed the greatest free radical quenching activity and superoxide anion scavenging activity associated with the highest volume of phenolic content material. Thus, this shows that the phenolicTable three Antioxidant activity ( ) of crude and fractionated extracts at several concentrations assayed by -carotene bleaching assayConcentrations (mg/ml) four eight 16 20 Antioxidant activity of crude methanol extract and its fractions Methanol extract 66.06 ?.63 74.73 ?.dw cxHexane fraction 23.92 ?.aw axEthyl acetate fraction 59.64 ?1.44 72.35 ?2.cw cxWater fraction 50.03 ?2.67 57.54 ?1.bw bxBHA 81.51 ?0.67ew 84.50 ?0.21dx 89.54 ?0.27dy 92.92 ?0.23dz42.17 ?three.77.84 ?.41cy 81.21 ?.cz52.62 ?2.21ay 56.80 ?two.ay72.87 ?1.73bx 74.51 ?0.Desmosterol Formula bx71.74 ?1.80by 74.79 ?1.byValues expressed are imply ?regular deviation of triplicate measurements.101623-68-1 Chemical name For precisely the same extract or standard with diverse concentrations, signifies inside the identical column with distinct letters (w-z) had been significantly distinct (p 0.05, ANOVA). For different extracts using the same concentration, indicates within the identical row with various letters (a-e) were considerably diverse (p 0.05, ANOVA). BHA was made use of because the normal.Phang et al. BMC Complementary and Option Medicine 2013, 13:243 http://biomedcentral/1472-6882/13/Page 7 ofTable four Inhibiton price (SOD activity) on the crude and fractionated extractsExtract/fractions Methanol Hexane Ethyl acetate Water BHA Inhibiton price ( ) 29.32 ?4.5 32.21 ?six.five 51.74 ?4.9 18.06 ?four.6 70.19 ?two.b b c a dIn vitro neutral red cytotoxicity assayEach value is expressed as imply ?regular deviation of triplicate measurements. Indicates with different letters (a-d) inside the same column are significantly diverse (p 0.PMID:23453497 05). Data are expressed as percentage of inhibition of superoxide radicals.content was positively correlated with DPPH radical scavenging activity and superoxide anion scavenging activity. As phenolic compounds have redox properties, this result is hardly surprising. The radical scavenging activity is normally related to the presence of hydroxyl substituents in aromatic rings, which contribute to their hydrogen donating activity [46]. Hence, the radical scavenging efficiency with the ethyl acetate extracts from Alpinia pahangensis may well happen to be contributed by the phenolic constituents. However, the crude methanol extract possessed the strongest decreasing activity against ferric ions and the highest antioxidant activity within the carotene bleaching assay. Lipid-soluble components are present within the crude methanol extract for the antioxidant activity shown in these two assays. It was also observed that use of polar solvents like aqueous methanol and ethyl acetate resulted in the extraction of elements displaying good antioxidant activity whereas extracts obtained from.