Figure 1Antioxidant activities of different solvent fractions from the methanol extract of M. buxifolia at different concentrations. Each value represents a mean ± SE (n = 3): (A) DPPH radical scavenging activity, (B) ABTS radical scavenging activity, (C) total antioxidant capacity, (D) superoxide scavenging activity. ASA = ascorbic acid; MFA = aqueous fraction of M. buxifolia; MFB = butanol fraction of M. buxifolia; MFE = ethyl acetate fraction of M. buxifolia; MFH = n-hexane fraction of M. buxifolia; MFM = methanol fraction of M. buxifolia; Rt. = rutin.
Figure 2Reducing power of different solvent fractions from the methanol extract of M. buxifolia fruits at varying concentrations. Each value represents a mean ± SE (n = 3). ASA = ascorbic acid; MFA = aqueous fraction of M. buxifolia; MFB = butanol fraction of M. buxifolia; MFE = ethyl acetate fraction of M. buxifolia; MFH = n-hexane fraction of M. buxifolia; MFM = methanol fraction of M. buxifolia.
Table 1Total phenolic and flavonoid content and extraction yield of M. buxifolia fractions
Plant fractions |
Total phenolics (mg GAE/g) |
Total flavonoids (mg rutin equivalent/g) |
Extraction yield (%) |
Methanol extract |
48.54 ± 2.9 |
42.045 ± 3.1 |
24.18 ± 3.2 |
n-Hexane fraction |
16.66 ± 1.3 |
4.110 ± 0.51 |
8.85 ± 1.1 |
Ethyl acetate fraction |
31.48 ± 2.4 |
28.89 ± 2.1 |
6.74 ± 0.7 |
Butanol fraction |
59.13 ± 2.6 |
36.51 ± 2.2 |
10.83 ± 0.9 |
Aqueous fraction |
42.91 ± 2.3 |
48.68 ± 2.8 |
4.56 ± 1.2 |
Table 2Antioxidant effect (EC50) on DPPH radicals, superoxide radicals, total antioxidant capacity and hydroxyl radicals of methanol extract and soluble fractions of M. buxifolia fruit
Plant extracts |
EC50
|
Scavenging ability on DPPH radicals |
Scavenging ability on superoxide radicals |
Phosphomolybdate assay |
Scavenging ability on hydroxyl radicals |
Scavenging ability on hydrogen peroxide radicals |
Scavenging ability on ABTS radicals |
Methanol fraction |
42.7 ± 1.62 |
53.2 ± 2.19 |
56.4 ± 2.06 |
103 ± 2.96 |
123.5 ± 2.17 |
186 ± 2.87 |
n-Hexane fraction |
>300 |
242.6 ± 3.61 |
203.2 ± 4.11 |
109 ± 3.21 |
>300 |
177 ± 3.26 |
Ethyl acetate fraction |
178.5 ± 3.25 |
88.5 ± 2.73 |
99.1 ± 2.36 |
260 ± 3.68 |
125.7 ± 2.83 |
179 ± 3.43 |
Butanol fraction |
24.1 ± 1.02 |
24.4 ± 0.89 |
58.2 ± 1.74 |
64.1 ± 3.15 |
89.3 ± 1.91 |
52.2 ± 2.57 |
Aqueous fraction |
56.5 ± 3.82 |
22.3 ± 1.35 |
45.2 ± 2.53 |
159.6 ± 2.55 |
69.2 ± 1.29 |
73.1 ± 3.26 |
Ascorbic acid |
20.4 ± 0.62 |
21.1 ± 0.86 |
24.8 ± 1.07 |
33.3 ± 1.34 |
24.8 ± 1.16 |
34.7 ± 1.51 |
Rutin |
19.5 ± 1.33 |
– |
– |
– |
28.2 ± 0.93 |
33.3 ± 1.08 |
Table 3Correlations between the EC50 values of antioxidant activities and phenolic and flavonoid content of M. buxifolia fruit
|
Correlation R²
|
EC50
|
Phenolics |
Flavonoids |
EC50 of scavenging ability on DPPH radicals |
0.9295∗
|
0.8554∗
|
EC50 of scavenging ability on superoxide |
0.7947†
|
0.9202∗
|
EC50 of phosphomolybdate assay |
0.7732†
|
0.9648∗
|
EC50 of scavenging ability on hydroxyl radicals |
0.1661 |
0.004 |
EC50 of scavenging ability on hydrogen peroxide radicals |
0.6779†
|
0.8995∗
|
EC50 of scavenging ability on ABTS radicals |
0.3992 |
0.2406 |