台灣產野甘草( Scoparia dulcis L. )之生藥學研究

Abstract

The genus Scoparia (Scrophulariaceae) is distributed in low altitude area of tropics and subtropics and has about 20 species in Americas tropic area, but only has one species in Taiwan. This species is Scoparia dulcis L.. According to the reports, It has effects of heat- clearing, clearing away toxin, inducing diuretic and subduing swelling. Modern pharmacological studies provides evidence that it can be used to anti-virus, anti-tumor, anti-hypertension and anti- hyperglycemia. Because it was often misused, it is a necessary to build up a method to determine its origin. We appraise the morphology (flowers, fruit ,seed and pollen) and histological anatomy (leaves and stems). This result can provide an useful method to identify Scoparia plants. The methanolic extract of dry entire plant of S. dulcis was partitioned and separated by chromatographic methods. Four known compounds were isolated, included glutinol (H-1), friedelin (H-2), betulinic acid (C-3), and 6-Methoxybenzoxazolinone (C-4). We set up a quantitative method of HPLC to determine the quantity of luteolin . This method has a high degree of sensitivity, reproducibility, precision and recovery rate. The result shows that the luteolin content of S.dulcis is 0.00197 ~ 0.00563 % and is the highest in the fruits than other parts. Analyse the peak height of S. dulcis described above by HPLC method. We discovered that the peak height ratio of the chosen 10 peaks, it can distinguish S. dulcis successfully. The entire internal transcribed spacer（ITS）region between 18S and 26S ribosomal DNA of S. dulcis is amplified by polymerase chain reaction（PCR）. The length of PCR product was 821 bp. Comparing the obtained sequence with the sequence of ITS from other higher plant species showed that the cloned sequence contained 66 bp of 26S rDNA, ITS region, and 142 bp of 18S rDNA. The length of ITS region was 613 bp, including 196 bp of ITS1,164 bp of 5.8S rDNA, and 253 bp of ITS2. The G+C contents of ITS1, 5.8S rDNA and ITS2 regions were 56 %, 62 % and 65 %, respectively. It can provide a clear and definite evidence to identify Scoparia species.