Antioxidant Activities and Polyphenolic Constituents of Bitter Bean Parkia Speciosa

Figures & data

Table 1  IC₅₀ values of antioxidant activities of P. speciosa empty pods

	IC50 (μg/mL)^§
	DPPH	ALP	SOD	ABTS	Metal chelation	Reducing power
PH	74.0 ± 4.99^a	7.72 ± 0.88^b	7.61 ± 0.13^c	80.7 ± 1.37^a	349 ± 18.2^a	379 ± 13.2^a
PE	64.2 ± 3.46^b	5.02 ± 1.06^c	12.9 ± 1.76^b	19.6 ± 0.44^c	319 ± 26.3^a	274 ± 16.1^b
Trolox	5.87 ± 0.16^c	19.6 ± 0.71^a	15.5 ± 0.85^a	29.0 ± 0.08^b	−	94.4 ± 5.40^c
EDTA	−	−	−	−	156 ± 9.10^b	−

Values are presented as mean ± SD (n = 3);

^§the IC₅₀ values were obtained from dose-effect curves by linear regression, indicating the concentration of test extracts or positive controls that inhibit or scavenge the radical formation by 50%.

Means within the same column with the different superscript letters are significantly different at P < 0.05 as analyzed by Duncan’s multiple range tests.

PH: aqueous extract; PE: ethanol extract; DPPH: 2,2-diphenyl-1-picrylhydrazyl radical scavenging; ALP: anti-lipid peroxidation; SOD: superoxide radical scavenging ; ABTS: 2,2’-azino-bis[3-ethylbenthiazoline-6-sulfonic acid] radical scavenging.

Figure 1  Antioxidant activities of P. speciosa empty pods. PH and PE were the aqueous and ethanol extracts, respectively. (a) Anti-lipid peroxidation activity; (b) SOD: Superoxide radical scavenging activity; (c) DPPH: 2,2-Diphenyl-1-picrylhydrazyl radical scavenging activity; (d) ABTS: 2,2’-azino-bis[3-ethylbenthiazoline-6-sulfonic acid] radical scavenging activity; (e) Metal chelating activity; (f) Reducing power. Data are presented as mean ± SD (n = 3); values with the different superscript letters are significantly different at P < 0.05 as analyzed by Duncan’s multiple range tests.

Figure 2  Total flavonoid and total phenolic contents of P. speciosa empty pods. PH and PE were the aqueous and ethanol extracts, respectively. Data are presented as mean ± SD (n = 3). *Indicates a significant difference (P < 0.05) between PH and PE as analyzed by Student’s paired t-test.

Figure 3  The content of polyphenolic constituents in P. speciosa empty pods. PH and PE were the aqueous and ethanol extracts, respectively. Data are presented as mean ± SD (n = 3). *Indicates a significant difference (P < 0.05) between PH and PE as analyzed by Student’s paired t-test.