Chemical constituents from a Gynostemma laxum and their antioxidant and neuroprotective activities

Chinese Medicine

Table 1 TOSC values of quercetin and quercetin analogues against peroxyl radicals

Compound	Concentration (μM)	TOSC value	sTOSC value (TOSC/μM)	rTOSC value
2	0.625	3.2	11.76 ± 1.27^a	4.08
	1.25	11.5	(R² = 0.9772)
	2.5	28.4
	5	41.7
	10	71.8
	20	94.4
3	2.5	7.7	3.39 ± 0.34^c	1.18
	5	27.3	(R² = 0.9717)
	10	38.1
	20	68.6
	40	92.0
4	1.25	8.0	5.54 ± 0.40^b	1.92
	2.5	12.1	(R² = 0.9894)
	5	28.2
	10	72.0
	20	93.6
	40	97.4
5	10	−0.8	0.44 ± 0.05^d	0.15
	20	7.1	(R² = 0.9781)
	40	12.9
	80	35.4
6	5	4.2	1.04 ± 0.03^d	0.36
	10	11.5	(R² = 0.9977)
	20	21.2
	40	41.2
	80	69.8
7	10	0.5	0.12 ± 0.02^d	0.04
	20	−0.1	(R² = 0.9268)
	40	2.8
	80	9.0
8	1.25	0.4	3.22 ± 0.15^c	1.12
	2.5	8.3	(R² = 0.9957)
	5	14.5
	10	32.5
	20	54.5
	40	88.6
	80	95.8
9	5	4.4	0.53 ± 0.07^d	0.18
	10	6.65	(R² = 0.9686)
	20	11
	40	13.2
	80	27.2

The TOSC values of each concentration are mean from three independent measurements. The sTOSC values were obtained from the slope of the linear regression line for the TOSC curves, and the rTOSC values were determined by dividing the sTOSC value of the sample by that of Trolox. The specific TOSC values of Trolox against peroxyl radicals were 2.88 ± 0.14 TOSC/μM. Values with different letters are significantly different from each other (ANOVA followed by Newman–Keuls multiple range test, p < 0.05)

ISSN: 1749-8546