The root-bark of the mulberry tree has been used as a medicine with antitussive, antiphlogistic, diuretic etc. in Korea. Among many kinds of mulberry trees, Morus Lhou has been widely cultivated in our country. In this experiment, three substances were obtained from the root-bark of Morus Lhou removed its cork layer by column chromatography of methanol extract. One of the substances was supposed as ${\alpha}$-amyrin acetate, another was alyceride, the other was confirmed as ${\beta}$-sistosterol by chemical and physical methods.

The five fractions from the barks of Zanthoxylum coreanum in Je-ju Island are examined in detail chromatographically in this paper. 37 compounds are detected in all of the fractions, and the compounds from each of fractions are found to be presumed that this plant is classified into the same group as that of the temperate Zanthoxylum taxa but is different from the tropical zanthoxylum taxa by its chemical components.

${\beta}-Sitosteryl-3-O-{\beta}-D-glucopyranoside$ was isolated from the seeds of Plantago asiatica (Plantaginaceae). The assignments of $^{13}C$ NMR spectra of ${\beta}-sitosterol$ and ${\beta}-sitosteryl-3-O-{\beta}-D-glucopyranoside$ were made by comparing with $^{13}C$ NMR spectra of cholesterol and $cholesteryl-3-O-{\beta}-D-glucopyranoside$. Our data indicate that the revision of previous $^{13}C$ NMR spectral assignment is needed.

In continuation of the previous papers, the presence of alkaloid, flavonoid, iridoid, terpenoid, steroid and saponin were screened with the usual test methods in another 53 species of Korean medicinal plants. The result is presented in the Table I.

93 species of medicinal plants in Korea were examined for the presence of iridoid. By using Trim-Hill reagent, the presence of iridoid was identified in 34 plant samples.

Methanol extracts of the roots of Atractylodes japonica (alba) (Compositae) and Gentiana scabra (Gentianaceae) were further fractionated with n-butanol, chloroform, n-hexane and water. Then each fraction was p.o. administered to an animal model of hepatitis caused by $CCl_4$ intoxication. Measurements of sleeping time of mice induced by hexobarbital administration indicated that n-butanol and chloroform fractions of Atractylodes japonica (alba), and chloroform and n-hexane fractions of Gentiana scabra showed significant liver protective activities. Measurements of the activities of serum transaminase, S-GOT and S-GPT appeared to support these results.

The antioxidant activities of the root of Panax ginseng and the root bark of Acanthopanax senticosus were compared by in vitro and in vivo experiments. The results of in vitro experiments showed no significant difference between the antioxidant activities of both crude drugs. However, the results of in vivo experiments showed much higher antioxidant activities in Panax ginseng than Acanthopanax senticosus, showing about 80 times greater activity.

In order to determine the effect of Oryeongsan reputed to have diuretic action since Han Dynasty and possible synergetic action of Dianthi Semen, Polygonum avicularis Herba, Kochiae Fructus and Akebiae Lignum, herbs with similar reputation, when added to the above prescription, their decoction powders were solved into distilled water and injected into rabbits through the ear vein. Upon the treatment, the excretion of sodium, potassium and chloride ion together with urine volume was kinetically determined. At the same time the clearance of plasma creatinine and sodium ion was determined and the following results were obtained. Every experimental group demonstrated diuretic action, though feable, of relatively long duration. The diuretic mechanism in the case of Oryeongsan made up by mixing the seperate extracts of individual components and Oryeongsan(A) plus Dianthi Semen was found to be inhibitory effect of renal tubular reabsorption in contrast to the case of Oryeongsan(A) plus Polygonum avicularis Herba, Kochiae Fructus or Akebiae Lignum in which case the diuretic mechanism was found to be glomerular vascular dilatation. The urinary excretion of potassium ion was increased in the case of Oryeongsan(A) plus Dianthi Semen, Kochiae Fructus of Akebiae Lignum whereas in the other cases no similar change was registered. The diuretic action was most remarkable in the case of Oryeongsan(A) plus Polygonum avicularis Herba followed by Oryeongsan(A) plus Kochiae Fructus, Oryeongsan(A) plus Dianthi Semen, extract mixture of individual component of Oryeongsan, Oryeongsan(A) and Oryeongsan(A) plus Akebiae Lignum decreasing order. The duration of diuretic action was found to be 90 minutes in the case of Oryeongsan and mixture of individual component of Oryeongsan, and 60 minutes in the case of Oryeongsan(A) plus Dianthi Semen, Kochiae Fructus or Akebiae Lignum in contrast to the case of Oryeongsan(A) plus Polygonum avicularis Herba which lasted up to 120 minutes.

The results of the comparison among the effects of decoction, extract powder and Gamiyoungsunjetongeum are as follows: In the experiment of analgesic effect in rats, having pain caused by Acetic acid, decoction showed a considerable reduction; extract powder did not show any notability and the effect of added decoction was conspicuous. The Anti-inflammatory effect of decoction was notable during $90{\sim}240minutes$, but extract powder also did not show any notability and added decoction showed a remarkable effect. In the experiment of inhibition on heat denaturation of serum rats, decoction and extract powder showed the inhibiting effects of 18.2%, 17.9% and the added decoction was even more remarkable(28.3%).

Twenty-seven medicinal plants were selected on the basis of folkloric reputation for the treatment of hypertension or related deseases. Two solvent fractions were prepared from methanol extract of each plant and tested for their effects on angiotensin converting enzyme (ACE) activities. Six solvent fractions showed more than 50% inhibition and four showed $40{\sim}50%$ inhibition at the conditions tested.

Six medicinal plants described in Dong-Ee-Bo-Gam as to be useful for hypertension treatment were evaluated their antihypertensive activity against Okamoto-SHR, an animal model of spontaneous hypertension. Ethanol extracts of plant samples were prepared and were p.o. administered once daily for 20 days. Average blood pressures of rats were measured during two weeks periods before drug administration. Then blood pressure of each rat was measured every three days during drug administration period. As a positive control, propranolol, ${\beta}-blocker$ was used and the blood pressures of test group rats were compared with those of negative and positive control group rats. Among 6 plant extracts, Acanthopanax sessiliflorum and Atractylodes japonica (alba) extracts appeared to exhibit antihypertensive activity.