Radical Scavenging Activity of Methanol Leaf Extracts of Orthosiphon stamineus.

Figures & data

Table 1.. Radical scavenging activity, total phenolic and soluble solid contents of methanolic extracts of Orthosiphon stamineus. leaf.^a.

				Antioxidant activity (%)
Location	State	Collection date^b.	Total phenolics (mg g^−1dry wt)	DPPH	NADH/PMS
Bohor Temak	Perlis	08/01/02	9.46	92.34 a	68.90 d
Kepala Batas	Pulau Pinang	26/05/02	7.61	88.68 b	72.81 bc
Bota Kanan	Perak	15/01/02	9.28	87.38 b	62.50 f
Kuala Nerang	Kedah	30/01/02	9.65	91.96 a	73.68 b
Kuching	Sarawak	20/09/01	9.59	83.75 d	71.27 c
Rawang	Selangor	26/12/02	8.86	88.49 bc	74.56 ab
Semonggok	Sarawak	05/03/02	9.77	90.31 b	72.80 b
Jengka	Pahang	09/04/02	7.36	62.82 e	72.59 b
Gua Musang	Kelantan	25/10/01	9.71	90.21 b	53.95 h
Parit	Perak	04/04/02	10.20	86.27 c	53.29 h
Pasir Puteh	Kelantan	25/07/02	6.69	88.83 bc	58.11 g
Bumbung Lima	Pulau Pinang	24/01/02	10.05	91.26 a	75.88 a
Quercetin				91.50 a	73.44 b
BHT				66.43 e	66.11 e

^a.The experiments were performed in January–February 2003. Leaves from white-flowered cultivars with similar fresh and dry weight (p > 0.05) were used for this experiment.

^b.Day/month/year.

Means within column with different letters indicate significantly different values (p < 0.05).

Figure 1. Chemical structures of markers.

Figure 2. UV spectra of methanolic leaf extracts of Orthosiphon stamineus. from different locations in Malaysia.

Figure 3. (a) HPLC chromatogram of reference markers, rosmarinic acid (RA), 3′-hydroxy-5,6,7,4′-tetramethoxyflavone (TMF), eupatorin (EUP), sinensetin (SEN). (b) HPLC fingerprint of methanol extract of Orthosiphon stamineus. leaf. Isocratic elution, methanol-water (pH 3)-tetrahydrofuran (4.5:5:0.5); flow rate, 1 ml/min; UV; 340 nm; temperature; 25°C; column; LiChrosorb RP-18.

Figure 4. Methanol-soluble solid of Orthosiphon stamineus. leaf.