HPTLC Densitometric Analysis of Orthosiphon stamineus. Leaf Extracts and Inhibitory Effect on Xanthine Oxidase Activity

Figures & data

Figure 1 Chemical structures of markers.

Figure 2 HPTLC profiles of methanol extracts of Orthosiphon stamineus.. (A) Two-dimensional chromatogram and; (B) Three-dimensional chromatogram. Eluent: chloroform:ethyl acetate (6:4, v/v); detection: 365 nm.

Table 1 Methanol-soluble solids, total flavonoid content, and content of polyphenol markers in Orthosiphon stamineus. leaf samples collected from different locations of Malaysia between 20 September 2002 and 25 July 2003.

				Concentration (% of dry weight)
Site	Location	MeOH-soluble solids (%)	Total flavonoids (mg quercetin equivalent/g dry wt)^†	TMF	SEN
I	Bohor Temak	18.20^a	4.65^b	0.05^d	0.10^e
II	Kepala Batas	9.00^de	4.70^b	0.10^a	0.23^c
III	Bota Kanan	10.09^d	4.60^b	0.05^c,d	0.10^e
IV	Kuala Nerang	16.50^b	4.62^b	0.08^b	0.28^b
V	Kuching	11.29^d	4.85^b	0.03^d	0.20^c
VI	Rawang	13.40^c	3.95^c	0.02^e	0.16^d
VII	Semonggok	15.26^b	4.60^b	0.04^d,e	0.09^e
VIII	Jengka	14.07^c	3.80^c	0.08^b	0.36^a
IX	Gua Musang	8.30^e	4.52^b	0.07^b,c	0.31^c
X	Parit	8.60^e	4.84^b	0.04^d,e	0.18^c
XI	Pasir Puteh	7.10^f	3.76^c	0.02^e	0.17^c,d
XII	Bumbung Lima	10.60^d	5.10^a	0.08^b	0.19^c

TMF, 3′-hydroxy-5,6,7,4′-tetramethoxyflavone; SEN, sinensetin.

*Means within column with different letters indicate significantly different values (p < 0.05). The experiments were performed in August 2003 using the HPTLC densitometric method. Leaves from white-flowered plants with similar fresh and dry weight (p > 0.05) were used for this experiment.

^†Flavonoid contents were determined by AlCl₃ coloration.

Figure 3 (A) Xanthine oxidase inhibitory activity of methanol extracts of Orthosiphon stamineus. leaf; (B) Dose-dependent activity of the extract from site II, Kepala Batas. Values are the means±SD (n = 3).

Figure 4 (A) Superoxide anion (NBT/X/XO system) scavenging activity of methanol extracts of Orthosiphon stamineus. leaf; (B) Dose-dependent activity of the extract from site II, Kepala Batas. Values are the means±SD (n = 3).