Low-density lipoprotein-antioxidant flavonoids and a phenolic ester from Plectranthus hadiensis var. tomentosus

Applied Biological Chemistry

Table 5 Antioxidant activity of 30%, 50%, 70%, and 95% ethanol extracts from freeze-dried and air-dried leaves and stems of PHT

Extracts	LDL oxidation inhibition (%) at 5 µg/mL	DPPH radical scavenging (%) at 100 µg/mL
Leaf
30FDL	NI	31.5 ± 0.1^c
50FDL	33.0 ± 0.0^c	82.2 ± 1.7^b
70FDL	43.7 ± 0.4^b	86.9 ± 1.6^a
95FDL	66.4 ± 1.4^a	80.6 ± 1.4^b
30ADL	NI	23.9 ± 1.1^e
50ADL	5.5 ± 0.0^e	27.6 ± 0.3^d
70ADL	4.7 ± 1.3^e	25.2 ± 0.7^e
95ADL	11.1 ± 1.7^d	21.2 ± 0.5^f
Stem
30FDS	NI	31.4 ± 0.4^e
50FDS	5.8 ± 0.7^e	47.3 ± 1.2^c
70FDS	82.6 ± 1.4^b	91.2 ± 0.9^b
95FDS	91.9 ± 0.3^a	98.6 ± 0.3^a
30ADS	4.3 ± 0.9^d	32.0 ± 0.0^f
50ADS	16.5 ± 3.5^c	41.9 ± 1.6^e
70ADS	15.7 ± 0.9^d	39.0 ± 2.2^e
95ADS	23.9 ± 1.6^b	39.0 ± 1.6^e

Values indicate mean ± SD (n = 3). NI: not inhibited
FDL freeze-dried leaves, FDS freeze-dried stems, ADL air-dried leaves, ADS air-dried stems
^a–fMeans not sharing a common letter within a column indicate that extracts from the same parts of PHT are significantly different (p < 0.05) by one-way ANOVA