Figure 1 Elution curve of fractionation of SPE with Sephadex LH-20.

Ten mL per fraction was collected. Each fraction was monitored at 280, 360, and 520 nm, and each fraction was also detected at 765 nm after reacted with Folin-Ciocaltaeu reagent. Fractions were combined according to their absorbance. Peaks at the line of wavelength of 280 and 765 nm represented phenolics compounds such as phenolic acids, flavonioids, or condensed tannins, peaks at 360 nm represented flavonoids, and peaks at 520 nm represented anthocyanins.

Figure 2 Free radical scavenging activity of extracts and fractions from small red bean.

Free radical scavenging activity against DPPH and ABTS was measured by the colorimetric methods as described in the Materials and methods. Results were expressed as means ± standard deviation (n = 3). (A) DPPH, and (B) ABTS.

Table 1:The yield, TPC, TFC, MAC, and CTC of extracts and fractions from small red bean.

Yield

TPC

TFC

MAC

CTC

(%)

(mg GAE/g)

(mg CE/g)

(mg CGE/g)

(mg CE/g)

CE

10.9 #

51.0 ± 1.8 d

24.8 ± 1.6 d

0.9 ± 0.1 d

31.8 ± 1.9 d

SPE

6.2 $

238.7 ± 18.9 c

154.8 ± 23.8 b

7.1 ± 0.2 b

169.5 ± 7.8 b

Fr I

43.8 *

11.6 ± 0.4 e

1.9 ± 0.2 e

nd

nd

Fr II

14.9 *

63.8 ± 2.2 d

21.4 ± 0.9 d

nd

nd

Fr III

11.5 *

394.6 ± 21.9 b

194.1 ± 6.7 a

43.9 ± 0.9 a

82.5 ± 7.0 c

Fr IV

10.4 *

434.5 ± 20.9 b

167.9 ± 9.4 a b

4.9 ± 0.7 c

139.4 ± 16.2 b

Fr V

16.8 *

536.4 ± 30.6 a

101.8 ± 12.4 c

0.1 ± 0.0 e

591.6 ± 34.1 a










# based on small red bean powders, $ based on CE, * based on SPE. GAE, gallic acid equivalents; CE, catechin equivalents; CGE,cyanidin 3-glucoside equivalents.nd: not detectable. Results were expressed as means ± standard deviation (n = 3), values with different letters within a column were significantly different (p< 0.05).

 

IC50 (mg/mL)

 

Antioxidant activity

 

DPPH

ABTS

 

FRAP (mmolFe2+  equivalents/100g)

ORAC (molTrolox equivalents/g)

CE

1.444 ± 0.034 b

0.603 ± 0.006 c

 

49.6 ± 0.3 d

2064.1 ± 127.4 d

 

SPE

0.279 ± 0.008 c d

0.106 ± 0.001 d e

 

261.1 ± 1.5 c

11659.6 ± 1674.4 c

 

Fr I

> 5

4.228 ± 0.123 a

 

6.7 ± 0.3 e

311.3 ± 7.6 e

 

Fr II

4.700 ± 0.243 a

0.942 ± 0.052 b

 

42.3 ± 0.3 d

3103.6 ± 253.3 d

 

Fr III

0.373 ± 0.008 c

0.064 ± 0.001 d e

 

339.0 ± 7.1 b

26085.9 ± 1896.5 a

 

Fr IV

0.376 ± 0.019 c

0.090 ± 0.000 d e

 

269.1 ± 8.6 c

14255.2 ± 789.8 b c

 

Fr V

0.128 ± 0.009 d e

0.036 ± 0.001 e

 

632.0 ± 24.1 a

16890.7 ± 141.0 b

 

Ascorbic acid

0.086 ± 0.006 e

0.062 ± 0.001 d e

 

 

 

-Tocopherol

0.158 ± 0.003 d e

0.124 ± 0.024 d

 

 

 

Trolox

0.164 ± 0.003 d e

0.092 ± 0.002 c

 

 

 

IC50 (mg/mL) against DPPH and ABTS free radicals and antioxidant activity of extracts and fractions from small red bean.

Results were expressed as means ± standard deviation (n = 3), values with different letters within a column were significantly different (p< 0.05).

 

cell lines

 

SK-OV-3

SW480

CAL 27

Hep G2

CE

0.897 ± 0.062 a

1.404 ± 0.110 a

1.070 ± 0.122 a

0.268 ± 0.021 a

SPE

0.113 ± 0.005 c

0.378 ± 0.030 b

0.176 ± 0.014 d

0.035 ± 0.002 c

Fr I

nd

1.212 ± 0.058 a

nd

nd

Fr II

nd

nd

0.863 ± 0.053 b

nd

Fr III

0.206 ± 0.010 b

1.035 ± 0.056 a

0.562 ± 0.063 c

0.155 ± 0.004 b

Fr IV

0.238 ± 0.012 b

0.307 ± 0.003 b

0.150 ± 0.011 d

0.038 ± 0.001 c

Fr V

0.03 5± 0.005 d

0.111 ± 0.005 c

0.035 ± 0.002 e

0.008 ± 0.000 d

IC50 (mg/mL) of extracts and fractions from small red bean against human cancer cells.

Results were expressed as means ± standard deviation (n = 3), values with different letters within a column were significantly different (p< 0.05).