Showing papers in "Planta Medica in 1992"
TL;DR: Scavenging of superoxide anions, inhibition of myeloperoxidase release and activity as well as a possible interference with the assembly of active NADPH-oxid enzyme may account for the inhibition of inflammatory process by gallic acid.
Abstract: Gallic acid was found to possess anti-inflammatory activity towards zymosan-induced acute food pad swelling in mice. In vitro studies on the mode of action of gallic acid revealed that this compound interferes with the functioning of polymorphonuclear leukocytes (PMNs). Scavenging of superoxide anions, inhibition of myeloperoxidase release and activity as well as a possible interference with the assembly of active NADPH-oxidase may account for the inhibition of inflammatory process by gallic acid. Structure-activity relationship analysis showed that the o-dihydroxy group of gallic acid is important for the inhibitory activity in vitro
389 citations
TL;DR: Results indicate that virucidal activity and cytotoxicity may have depended upon the viral envelope and cell membrane, respectively.
Abstract: Garlic (Allium sativum) has been shown to have antiviral activity, but the compounds responsible have not been identified. Using direct pre-infection incubation assays, we determined the in vitro virucidal effects of fresh garlic extract, its polar fraction, and the following garlic associated compounds: diallyl thiosulfinate (allicin), allyl methyl thiosulfinate, methyl allyl thiosulfinate, ajoene, alliin, deoxyalliin, diallyl disulfide, and diallyl trisulfide. Activity was determined against selected viruses including, herpes simplex virus type 1, herpes simplex virus type 2, parainfluenza virus type 3, vaccinia virus, vesicular stomatitis virus, and human rhinovirus type 2. The order for virucidal activity generally was: ajoene > allicin > allyl methyl thiosulfinate > methyl allyl thiosulfinate. Ajoene was found in oil-macerates of garlic but not in fresh garlic extracts. No activity was found for the garlic polar fraction, alliin, deoxyalliin, diallyl disulfide, or diallyl trisulfide. Fresh garlic extract, in which thiosulfinates appeared to be the active components, was virucidal to each virus tested. The predominant thiosulfinate in fresh garlic extract was allicin. Lack of reduction in yields of infectious virus indicated undetectable levels of intracellular antiviral activity for either allicin or fresh garlic extract. Furthermore, concentrations that were virucidal were also toxic to HeLa and Vero cells. Virucidal assay results were not influenced by cytotoxicity since the compounds were diluted below toxic levels prior to assaying for infectious virus. These results indicate that virucidal activity and cytotoxicity may have depended upon the viral envelope and cell membrane, respectively. However, activity against non-enveloped virus may have been due to inhibition of viral adsorption or penetration.(ABSTRACT TRUNCATED AT 250 WORDS)
307 citations
TL;DR: The hypoglycemic activity of olive leaf was studied and one of the compounds responsible for this activity was oleuropeoside, which showed activity at a dose of 16 mg/kg, which demonstrated antidiabetic activity in animals with alloxan-induced diabetes.
Abstract: The hypoglycemic activity of olive leaf was studied. Maximum hypoglycemic activity was obtained from samples collected in the winter months, especially in February. One of the compounds responsible for this activity was oleuropeoside, which showed activity at a dose of 16 mg/kg. This compound also demonstrated antidiabetic activity in animals with alloxan-induced diabetes. The hypoglycemic activity of this compound may result from two mechanisms: (a) potentiation of glucose-induced insulin release, and (b) increased peripheral uptake of glucose.
182 citations
TL;DR: The total amount of anthocyanins and polyphenols present in the berries of several cultivars of Ribes, Rubus, and Vaccinium genera is determined and Ribes nigrum extracts exhibit the highest activity, being the richest in both Anthocyanin and Polyphenols.
Abstract: In view of the pharmacological interest in phenolic substances, we have determined the total amount of anthocyanins and polyphenols present in the berries of several cultivars of Ribes, Rubus, and Vaccinium genera. The in vitro antiradical activity of the crude extracts on chemically-generated superoxide radicals as well as the inhibitory activity towards the enzyme xanthine oxidase were studied. All the crude extracts examined showed a remarkably high activity towards chemically-generated superoxide radicals. The activities were greater than those expected on the basis of the quantities of anthocyanins and polyphenols present in the samples. Furthermore, the extracts showed a certain inhibitory activity towards xanthine oxidase. Ribes nigrum extracts exhibit the highest activity, being the richest in both anthocyanins and polyphenols. On the other hand, Ribes rubrum extracts seem to contain more active substances than the other crude extracts.
180 citations
TL;DR: The results demonstrate that there are two alliinase activities in garlic, that a stomach acid-resistant coating on garlic powder tablets is necessary for thiosulfinate release, and that carefully prepared garlic powder can release similar amounts of totalThiosulfinates to whole garlic cloves.
Abstract: The effects of pH, neutralization after acidification, time, and temperature on the yield of dialkyl thiosulfinates released from garlic powder and garlic cloves were determined. All dipropenyl thiosulfinates (allicin, 1-propenyl allyl, and allyl 1-propenyl) were formed at an optimum pH of 4.5-5.0. The methyl propenyl thiosulfinates (allyl methyl + methyl allyl and 1-propenyl methyl + methyl 1-propenyl) and dimethyl thiosulfinate were optimally formed at pH 6.5-7.0 and pH 5.5, respectively. Below pH 3.6 no thiosulfinates were formed. Neutralization of the pH failed to restore thiosulfinate generation from garlic previously incubated at pH 3 or below. Thus, alliinase is completely and irreversibly inhibited by the acidic conditions found in the stomach. The dipropenyl thiosulfinates were completely formed in 0.3 min at 37 degrees C, while the methyl thiosulfinates were not completely formed until 3.5 min. Allyl 1-propenyl thiosulfinate was the most rapidly formed, and the most unstable, thiosulfinate. The stability of the dipropenyl thiosulfinates was improved at pH 4.5 or lower. Drying garlic at 60 degrees C had no effect on alliin or the rate of formation of the dipropenyl thiosulfinates, but decreased trans-1-propenylcysteine sulfoxide (isoalliin) and the rate of formation of the methyl thiosulfinates. The results demonstrate that there are two alliinase activities in garlic, that a stomach acid-resistant coating on garlic powder tablets is necessary for thiosulfinate release, and that carefully prepared garlic powder can release similar amounts of total thiosulfinates to whole garlic cloves.
177 citations
Metz1
TL;DR: The dried aqueous extract of Harpagophytum procumbens and its main iridoid glycoside, harpagoside, have been evaluated for anti-inflammatory and analgesic effects in mice and rats, in order to validate or invalidate the involvement of this compound in such properties.
Abstract: The dried aqueous extract of Harpagophytum procumbens (Pedaliaceae) and its main iridoid glycoside, harpagoside, have been evaluated for anti-inflammatory and analgesic effects in mice and rats, in order to validate or invalidate the involvement of this compound in such properties. This extract exerted significant and dose-dependent anti-inflammatory and analgesic effects, from the dose 100 mg of dried secondary roots/kg, the first being obtained on an acute inflammatory process (carrageenan-induced edema test in rats) and the second being obtained against a chemical stimulus (writhing test in mice). Harpagoside does not appear to be involved in anti-inflammatory properties, since this iridoid glycoside did not protect against carrageenan inflammatory effects when it was used at 5 and 10 mg/kg; 5 mg corresponding to the quantity contained in 400 mg of dried secondary roots. The main iridoid glycoside of H. procumbens appears to be implicated in the peripheral analgesic properties of this species, but other compounds have to be involved, since the dose of 10 mg/kg exerted a significant protective effect. The absence of the activity of H. procumbens after an acid treatment (0.1 N hydrochloric acid), stomach, suggests the use of a suitable galenic preparation in order to protect the active principles from the action of the acid released in the stomach.
157 citations
152 citations
TL;DR: Three monoterpenes induced the detoxifying enzyme glutathione S-transferase in several mouse target tissues and the alpha,beta-unsaturated ketone system in carvone appeared to be critical for the high enzyme-inducing activity.
Abstract: Bioassay-directed fractionation of dill weed oil and caraway oil, respectively, from the plants Anethum graveolens L. and Carum carvi L. (Umbelliferae) has led to the isolation of three monoterpenes, anethofuran (1), carvone (2), and limonene (3). Their structures were determined on the basis of spectral analysis. These compounds induced the detoxifying enzyme glutathione S-transferase in several mouse target tissues. The alpha,beta-unsaturated ketone system in carvone appeared to be critical for the high enzyme-inducing activity.
144 citations
TL;DR: Seven of the lignans isolated from Schisandra chinensis, S. rubriflora, and Kadsura longipedunculata have anti-oxidant activities, and schisanhenol was the most active one.
Abstract: The anti-oxidant activity of nine dibenzocyclooctene lignans isolated from Schisandra chinensis, S. rubriflora, and Kadsura longipedunculata, respectively, was studied. Seven of the 9 lignans (1 mM) inhibited iron/cysteine-induced lipid peroxidation (malondialdehyde, MDA, formation) of rat liver microsomes as well as superoxide anion production in the xanthine/xanthine oxidase system. The actions of the 7 lignans were much more potent than vitamin E at the same concentration of 1 mM. Among the lignans, schisanhenol was the most active one. This compound also prevented the decrease of membrane fluidity of liver microsomes induced by iron/cysteine. The results indicated that seven of the lignans such as schisanhenol have anti-oxidant activities.
143 citations
TL;DR: Both extracts failed to show any spermatotoxic effects and gained in weights of sexual organs and increased sperm motility and sperm counts were observed in both groups of extract-treated male mice, however, these changes were highly significant in the A. galanga-treated group.
Abstract: Acute (24 h) and chronic (90 days) oral toxicity studies on the ethanolic extracts of the rhizomes of Alpinia galanga and Curcuma longa were carried out in mice. Acute dosages were 0.5, 1.0, and 3 g/kg body weight while the chronic dosage was 100 mg/kg/day as the extract. All external morphological, hematological, and spermatogenic changes, in addition to body weight and vital organ weights were recorded. During this investigation no significant mortality as compared to the controls was observed. The weight gain in the A. galanga treated animals was significant as in the control group while the C. longa-treated animals gained no significant weight after chronic treatment. C. longa treatment induced significant changes in heart and lungs weights upon chronic treatment. Hematological studies revealed a significant rise in the RBC level of A. galanga-treated animals and a significant fall in the WBC and RBC levels of the C. longa-treated animals as compared to the controls. The gain in weights of sexual organs and increased sperm motility and sperm counts were observed in both groups of extract-treated male mice, however, these changes were highly significant in the A. galanga-treated group. Both extracts failed to show any spermatotoxic effects.
142 citations
TL;DR: Diallyl disulfide and allyl mercaptan were identified as metabolites of allicin, whereby diallyl Disulfide probably is the metabolic precursor of allyl Mercaptan as shown by perfusion with dially l disulfides alone.
Abstract: The metabolic and kinetic behaviour of different garlic (Allium sativum L., Alliaceae) constituents were investigated in the isolated perfused rat liver, using aqueous extracts of garlic powder as well as isolated allicin, the main product of the enzymatic degradation of alliin. Allicin (allyl thiosulfinate) showed a remarkable first pass effect and passed the liver unmetabolized only at high concentrations which caused considerable cell injuries. Diallyl disulfide and allyl mercaptan were identified as metabolites of allicin, whereby diallyl disulfide probably is the metabolic precursor of allyl mercaptan as shown by perfusion with diallyl disulfide alone. The metabolites diallyl disulfide and allyl mercaptan could be determined in the perfusion medium as well as in the bile and the liver tissue. Other degradation products of garlic were also investigated in this model. Ajoenes and vinyldithiins were detected in perfusion medium after liver passage but no metabolites of them could be identified up to now.
TL;DR: In the 5-LO and CO test the garlic extracts are slightly superior to the wild garlic extracts whereas, in the TA test, no differences could be found, underline the usefulness of wild garlic as a substitute of garlic.
Abstract: Extracts of wild garlic (Allium ursinum) and garlic (A. sativum) with defined chemical compositions were investigated for their in vitro inhibitory potential on 5-lipoxygenase (LO), cyclooxygenase (CO), thrombocyte aggregation (TA), and angiotensin I-converting enzyme (ACE). The inhibition rates as IC50 values of both extracts for 5-LO, CO, and TA showed a good correlation with the %-content of the major S-containing compounds (thiosulfinates and ajoenes) of the various extracts. In the 5-LO and CO test the garlic extracts are slightly superior to the wild garlic extracts whereas, in the TA test, no differences could be found. In the ACE test the water extract of the leaves of wild garlic containing glutamyl-peptides showed the highest inhibitory activity followed by that of the garlic leaf and the bulbs of both drugs. The comparative studies underline the usefulness of wild garlic as a substitute of garlic.
TL;DR: The effects of three compounds, digitolutein, rubiadin 1-methyl ether and damnacanthal, extracted from the stem bark and the roots of Morinda lucida Benth on the growth of Plasmodium falciparum in vitro were investigated.
Abstract: The effects of three compounds, digitolutein (1), rubiadin 1-methyl ether (2) and damnacanthal (3) extracted from the stem bark and the roots of Morinda lucida Benth. on the growth of Plasmodium falciparum in vitro were investigated. The number of parasites (schizonts) decreased significantly in a dose-dependent manner, and 100% of inhibition was obtained with 30 to 40 micrograms of each compound tested. The IC50 values were calculated.
TL;DR: Reinvestigation of the polar fractions from the stem bark of STEMMADENIA MINIMA A. Gentry afforded two known and four new lignan glucosides that were deduced by spectroscopic and chemical methods.
Abstract: Reinvestigation of the polar fractions from the stem bark of STEMMADENIA MINIMA A. Gentry (Apocynaceae) afforded two known and four new lignan glucosides. Their structures were deduced by spectroscopic and chemical methods.
TL;DR: Oral administration of Picroliv resulted in a significant increase in haemagglutinating antibody (HA) titre, plaque forming cells (PFC), and delayed hypersensitivity (DTH) response to SRBC, and induced a high degree of protection in golden hamsters against challenge infection with Leishmania donovani promastigotes.
Abstract: Picroliv, a standardised fraction from root and rhizome of PICRORHIZA KURROA, consisting of iridoid glycosides and shown to be responsible for its hepatoprotective activity, was studied for immunostimulant activity. Oral administration of Picroliv (10 mg/kg x 7 days) in mice prior to immunization with sheep red blood cells (SRBC) resulted in a significant increase in haemagglutinating antibody (HA) titre, plaque forming cells (PFC), and delayed hypersensitivity (DTH) response to SRBC. Picroliv enhanced the non-specific immune response characterized by an increase in macrophage migration index (MMI), [ (14)C]-glucosamine uptake, phagocytosis of [ (14)C]-leucine labelled ESCHERICHIA COLI, chemiluminescence of peritoneal macrophages, and higher uptake of [ (3)H]-thymidine in the lymphocytes of treated mice. It also induced a high degree of protection in golden hamsters against challenge infection with LEISHMANIA DONOVANI promastigotes.
TL;DR: Hyperforin, which is responsible for the oil's therapeutic activity, could, for the first time, be identified and quantitatively determined by TLC and HPLC after solid-phase extraction.
Abstract: Hyperici Oleum (St. John's wort oil) used in wound healing contains no hypericin. By using the sunlight maceration method described in the supplement to DAB 6 (EB 6), lipophilic breakdown products of this compound are obtained which lend the oil its red colour. Hyperforin, which is responsible for the oil's therapeutic activity could, for the first time, be identified and quantitatively determined by TLC and HPLC after solid-phase extraction. The stability of hyperforin is limited; sufficient shelf-life could only be achieved by hot maceration of dried flowers with eutanol G and storage in the absence of air. By gradient HPLC further polar hyperforin analogues were detected in those St. John's wort oils in which hyperforin had decomposed. At the same time flavonoids and xanthones could be identified. A procedure for the quantitative determination of flavonoids in St. John's wort was validated. The action of light during preparation of the oil led to a rise in the content of flavonoids.
TL;DR: It may be concluded that extracts of the leaves of Tinospora cordifolia have an insulin-like action and can significantly reduce the blood glucose but not the total lipid levels in normal rabbits and in alloxan-induced diabetic rabbits.
Abstract: The aqueous, alcoholic, and chloroform extracts of the leaves of Tinospora cordifolia were administered in doses of 50, 100, 150 and 200 mg/kg body weight to normal and alloxan-diabetic rabbits. The blood glucose and total lipid levels were estimated before and 2, 4, 6, and 8 hours after administration of the extract. The extract exerted a significant (P less than 0.5) hypoglycaemic effect in normal as well as in alloxan-treated rabbits. The extracts, however, had no significant (P greater than 0.05) effect on total lipid levels in normal as well as in alloxan-treated diabetic rabbits. The doses used did not show acute toxicity or result in behavioural changes. From this study, it may be concluded that extracts of the leaves of Tinospora cordifolia have an insulin-like action and can significantly reduce the blood glucose but not the total lipid levels in normal rabbits and in alloxan-induced diabetic rabbits.
TL;DR: Andrographolide from the herb Andrographis paniculata (whole plant) per se produces a significant dose dependent choleretic effect as evidenced by increase in bile flow, bile salt, and bile acids in conscious rats and anaesthetized guinea pigs.
Abstract: Andrographolide from the herb Andrographis paniculata (whole plant) per se produces a significant dose (1.5-12 mg/kg) dependent choleretic effect (4.8-73%) as evidenced by increase in bile flow, bile salt, and bile acids in conscious rats and anaesthetized guinea pigs. The paracetamol induced decrease in volume and contents of bile was prevented significantly by andrographolide pretreatment. It was found to be more potent than silymarin, a clinically used hepatoprotective agent.
TL;DR: Bioassay-guided fractionation of IPA resulted in isolation of the antispasmodically acting isoprenoids beta-damascenone and E-phytol, which were found to be in the same range as that of papaverine, a general spasmolytic agent.
Abstract: The crude extract (IPA) of the plant Ipomoea pes-caprae (L.) R. Br. has previously been shown to antagonize smooth muscle contractions induced by several agonists via a non-specific mechanism. Bioassay-guided fractionation of IPA resulted in isolation of the antispasmodically acting isoprenoids beta-damascenone and E-phytol. Their antispasmodic potencies were found to be in the same range as that of papaverine, a general spasmolytic agent. This effect was suggested to play a role in the previously observed anti-inflammatory activity of IPA by interfering with the contraction of endothelial cells. Severe vascular contraction has been shown to be involved in the dermatitis caused by toxic jellyfishes. It is possible that beta-damascenone and E-phytol, by interfering with the contraction of vascular smooth muscle cells, are partly responsible for the previously reported effectiveness of IPA in the treatment of such dermatitis.
TL;DR: The C-glycosylflavones were found to have remarkable anti-hepatotoxic activities against CCl4 and galactosamine cytotoxicity in primary cultured rat hepatocytes and their structures were elucidated on the basis of chemical and spectral data.
Abstract: From the leaves of Allophyllus edulis var. edulis and Allophyllus edulis var. gracilis nine C-glycosylflavones have been isolated and identified as schaftoside (8), vicenin-2 (9), lucenin-2 (10), isovitexin 2"-O-rhamnoside (11), cerarvensin 2"-O-rhamnoside (12), vitexin 2"-O-rhamnoside (13), isoorientin 2"-O-rhamnoside (15), orientin 2"-O-rhamnoside (16) and saponarin (17). In addition, gallic acid (2), the phenol C-glycosides bergenin (3) and 11-O-galloylbergenin (4), three flavonol 3-O-rhamnosides and a new C-glycosylflavone identified as mollupentin 2"-O-rhamnoside (14) were obtained from the leaves of Allophyllus edulis var. edulis. Their structures were elucidated on the basis of chemical and spectral data. For the first time the C-glycosylflavones were found to have remarkable anti-hepatotoxic activities against CCl4 and galactosamine cytotoxicity in primary cultured rat hepatocytes. Structure-activity relationships are discussed.
TL;DR: Three water-soluble polysaccharides have been isolated from flower buds of Hibiscus sabdariffa L. (HIB 1,2,3) and the main acidic fraction was contaminated with lipopolysaccharide, and therefore its shown activity has to be discussed carefully.
Abstract: Three water-soluble polysaccharides have been isolated from flower buds of Hibiscus sabdariffa L. (HIB 1,2,3). The neutral polysaccharides (HIB 1 and 2) are composed of arabinans and arabinogalactans of low relative molecular mass. The major fraction was investigated by methylation analysis, pectinase-treatment, mild acid hydrolysis and NMR studies, and it was shown to be a pectin-like molecule (Mr = 10(5)d). The main chain is composed of alpha-1,4-linked GalA (24% methyl-esterified) and alpha-1,2-linked Rha. Side chains are built of Gal and Ara and are connected to the main chain via C-4 of every third Rha. Its structure seems to be different from polysaccharide structures described in other species of the Hibiscus genus and the Malvaceae family. All fractions were assayed for possible immune-modulating effects. All fractions showed some activity, but the main acidic fraction was contaminated with lipopolysaccharide, and therefore its shown activity has to be discussed carefully.
TL;DR: Four water-soluble constituents, salvianolic acids D, E, ethyl lithospermate, and isoferulic acid were isolated from SALVIA MILTIORRHIZA and their chemical structures were determined by chemical and spectral analysis.
Abstract: Four water-soluble constituents, salvianolic acids D, E, ethyl lithospermate, and isoferulic acid were isolated from SALVIA MILTIORRHIZA. Salvianolic acids D and E are new depsides. Their chemical structures were determined by chemical and spectral analysis. The structure of salvianolic acid D was finally confirmed by comparison with a synthetic product.
TL;DR: These experiments suggest that in the course of metabolism of lignans, firstly a cleavage of the glycosidic bond occurred and then demethylation of the phenolic methoxy group in the alimentary tract followed.
Abstract: Structural transformation of arctiin and tracheloside, major components of seeds of Arctium lappa and Carthamus tinctorius, were investigated using rat gastric juice (pH 1.2-1.5) and rat large intestinal flora in vitro. Quantitative analysis of lignans and their metabolites was carried out by high performance liquid chromatography. Both lignans were stable in rat gastric juice and arctiin was rapidly transformed to arctigenin in rat large intestinal flora, followed by conversion to the major metabolite, 2-(3",4"-dihydroxybenzyl)-3-(3',4'-dimethoxybenzyl)-butyrolactone. On the other hand, tracheloside also decreased dependently with time and was converted to trachelogenin and its major metabolite, 2-(3",4"-dihydroxybenzyl)-3-(3',4'-dimethoxybenzyl)-2-hydroxybutyrola ctone. These experiments suggest that in the course of metabolism of lignans, firstly a cleavage of the glycosidic bond occurred and then demethylation of the phenolic methoxy group in the alimentary tract followed.
TL;DR: Of 13 methanol extracts tested, 5 from Gongronema latifolia, Dorstenia multiradiata, Picralima nitida, Cola attiensis, and Desmodium gangeticum were active at concentrations of 50 micrograms/ml or less against a visceral Leishmania isolate.
Abstract: Extracts of eleven plants used in Nigerian traditional medicine have been evaluated for possible antileishmanial activity using a radiorespirometric microtest technique based on in vitro inhibition of catabolism of 14CO2 from a battery of 14C-substrates by promastigotes. Of 13 methanol extracts tested, 5 from Gongronema latifolia, Dorstenia multiradiata, Picralima nitida, Cola attiensis, and Desmodium gangeticum, were active at concentrations of 50 micrograms/ml or less against a visceral Leishmania isolate.
TL;DR: Coniferaldehyde, scopoletin, sinapaldehyde, and syringaldehyde were isolated from an aqueous extract of Senra incana and all four compounds inhibited prostaglandin synthetase in a dose-dependent way.
Abstract: Coniferaldehyde, scopoletin, sinapaldehyde, and syringaldehyde were isolated from an aqueous extract of Senra incana. All four compounds inhibited prostaglandin synthetase in a dose-dependent way. Compared to aspirin, the potency of coniferaldehyde and scopoletin was about five times higher, whereas syringaldehyde and sinapaldehyde had about half the potency of this reference compound. On topical application, sinapaldehyde and scopoletin dose-dependently inhibited ethyl phenylpropiolate-induced edema of the rat ear. The active dose range was 1-10 micrograms/ear. Higher doses had a lower effect. Syringaldehyde was active in the range 20-100 micrograms/ear, whereas the effect of coniferaldehyde was inconclusive. Coniferaldehyde and sinapaldehyde inhibited electrically induced contractions of the guinea pig ileum in a dose-dependent way. Syringaldehyde showed a weak inhibition at a concentration of 550 microM.
TL;DR: Saikosaponin d, isolated from the roots of Bulpleurum falcatum L. was investigated for both its inactivating effects on some viruses and its antiviral effects against the viruses in vitro.
Abstract: Saikosaponin d, isolated from the roots of Bulpleurum falcatum L was investigated for both its inactivating effects on some viruses and its antiviral effects against the viruses in vitro Saikosaponin d at a concentration of more than 5 microM had direct inactivating effects on both measles virus and herpes simplex virus after incubation of the viruses with the agent for more than 10 min at room temperature In contrast, exposure of poliovirus to even 500 microM of saikosaponin d resulted in no loss of infectivity, while the same concentration of saikosaponin d induced complete loss of infectivity in both measles virus and herpes virus In addition, saikosaponin d was ineffective against the replication of measles virus, herpes virus, and polio virus at a concentration of 01 microM, whereas saikosaponin d did not induce an inhibitory effect on the growth of Vero cells, when Vero cells were treated with saikosaponin d 24 h before the inoculation (pretreatment) and immediately or 24 h after the infection of the viruses (post-treatment)