Showing papers in "Planta Medica in 1989"

Polysaccharides in pharmacy: current applications and future concepts.

Abstract: Polysaccharides constitute a structurally diverse class of biological macromolecules with a wide range of physicochemical properties, which are the basis for the different applications in the broad field of pharmacy and medicine. Besides the classical applications of these biopolymers in industry and pharmaceutical practice, the relatively new field of the physiologically active polymers will be discussed. Some examples will be given for the so-called immune-modulating antitumor polysaccharides which have been shown to be prominent candidates for an adjuvant tumor therapy.

Ellagitannins as active constituents of medicinal plants.

Abstract: Isolation and structure determination, accompanied by measurement of various biological activities of each isolated tannin, particularly of ellagitannins, have brought about a marked change in the concept of tannins as active constituents of medicinal plants. Their biological activities should now be discussed on the basis of the structural differences among each tannin, in a way similar to that of the other types of natural organic compounds. The anti-tumor activity exclusively exhibited by several oligomeric ellagitannins, and their anti-HIV activities are examples of such biological activities. The inhibitory activity against lipid peroxidation, which is different in the strength among tannins of various structures, is exhibited in general more strongly by ellagitannins than by the other types of tannins of similar structures. The radical-scavenging activities of tannins as the mechanism of their inhibition, which is regarded to participate in several biological activities of tannins, have been supported by the ESR spectral measurements. Other biological activities, i.e., inhibition of mutagenicity of carcinogens, inhibition of tumor promotion, etc., have been found for tannins including ellagitannins.

Silybin Dihemisuccinate Protects Against Glutathione Depletion and Lipid Peroxidation Induced by Acetaminophen on Rat Liver

Abstract: Acetaminophen hepatotoxicity is characterized by glutathione depletion, cellular necrosis, and, in some instances, by the induction of lipid peroxidation. Silybin dihemisuccinate, a soluble form of the flavonoid silymarin, protects rats against liver glutathione depletion and lipid peroxidation induced by acute acetaminophen intoxication. Other biochemical parameters such as serum transaminases did not show the drastic increase observed under acetaminophen intoxication when animals were treated with the flavonoid. Preliminary results suggest that silybin dihemisuccinate may be another antidote against acetaminophen hepatotoxicity.

TLC and HPLC Analysis of Alkamides in Echinacea Drugs1,2.

Abstract: HPLC and TLC methods are presented for the analysis of the alkamides in ECHINACEA PURPUREA, E. ANGUSTIFOLIA, and E. PALLIDA. The roots of E. PURPUREA and E. ANGUSTIFOLIA contain different structural types of alkamides, while the roots of E. PALLIDA were almost void of amides. In contrast, the aerial parts of the three ECHINACEA species yielded very similar alkamide patterns. The methods are suitable for the analytical characterization and standardization of the three species.

Selectivity of silymarin on the increase of the glutathione content in different tissues of the rat.

Abstract: Silymarin, a flavonoid extracted from the seeds of the milk thistle, Silybum marianum, increases the redox state and the total glutathione content of the liver, intestine, and stomach of the rat The same treatment does not affect the levels of the tripeptides in the kidney, lung, and spleen This selective effect of the flavonoid on the digestive organs is ascribed to its pharmacokinetics on the digestive track, where the biliary concentration of silymarin is increased and maintained via the entero-hepatic circulation

Traditional herbal medicines--the role of polyphenols.

Abstract: The polyphenol composition of some traditional herbal remedies is reviewed. Polyphenols probably act in such remedies by virtue of their astringent action and current views on the molecular basis of this property are outlined and discussed.

Quantitative Determination of Allicin and Alliin from Garlic by HPLC

Abstract: The procedure for allicin synthesis could be improved. The time for HPLC analysis of allicin was shortened by the application of different isocratic elution systems. Calibration was performed by use of an allicin/silica gel adsorbate as external standard and its allicin content could be confirmed by different methods. L-(+)-Alliin was synthesized and applied as external standard for the quantitative determination of alliin by HPLC. Diastereoisomers had been separated by repeated recrystallization. Fresh Allium sativum bulbs from different origins were analyzed with respect to allicin content after complete enzymatic conversion of alliin; allicin contents found were in the range of 0.4%. The corresponding alliin contents were in the range of 0.9%. For a comparative evaluation of the alliin- and the allicin-HPLC determination methods, commercially available garlic preparations were analyzed, demonstrating that both methods are appropriate. However, the application of the HPLC system for allicin determination, in addition to providing information on the alliin-dependent allicin-generating capacity, enables the simultaneous quantification of allicin transformation products, such as ajoenes, dithiins, and alkyl sulfides. It was found that, for quantitative GLC analysis of allicin, allicin has to be used as an external standard.

Mechanisms of hypoglycemic activity of ganoderan B: a glycan of Ganoderma lucidum fruit bodies

Abstract: Ganoderan B increased the plasma insulin level in normal and glucose-loaded mice but elicited no effect on insulin binding to isolated adipocytes. Administration of ganoderan B elicited significant increases of the activities of hepatic glucokinase, phosphofructokinase and glucose-6-phosphate dehydrogenase, decreased the hepatic glucose-6-phosphate and glycogen synthetase activities and did not affect the activities of hexokinase and glycogen phosphorylase. Ganoderan B reduced the glycogen content in the liver but had no influence on total cholesterol and triglyceride levels in the plasma and liver.

Search for new plant constituents with potential antiphlogistic and antiallergic activity.

Abstract: Structure-activity relationships obtained from in vitro screening results obviously indicate that the highest inhibition effects on cyclooxygenase and 5-lipoxygenase are found amongst the class of phenolic compounds (flavonoids, polyphenols, coumestans, phenol carboxylic acids) and arachidonic acid analogous (alkylamides, retinoids, arylheptanoids, thiosulfinates, sulfinyl disulfides). The antiinflammatory activities of some triterpenenic acids, sesquiterpene lactones, and polysaccharides may be due to their immunomodulating activities on the complement and/or T-lymphocyte populations, respectively. In the search for potential antiallergic and antiasthmatic compounds, the thiosulfinates of onion were found to be active principles of the drug. The mechanism of action of some other antiallergic plant drugs (i.e. Tylophora asthmatica, Adhatoda vasica, etc.) has not yet been clarified.

Taspine is the cicatrizant principle in Sangre de Grado extracted from Croton lechleri.

Abstract: Activite cicatrisante et non carcinogene de la taspine et du «Sangre de Grado» extraits du «Croton lechleri», arbre peruvien

The antiviral action of lignans.

Abstract: A total of 18 purified lignans was evaluated for antiviral activity against murine cytomegalovirus (CMV) and Sindbis virus, by means of different treatment regimens. Podophyllotoxin and alpha-peltatin were the most potent compounds, and they apparently inhibited murine CMV at an essential early step in the replication cycle after the adsorption of virus to the cells. On the other hand, justicidin B and the diphyllin derivatives were much more effective against Sindbis virus, and 12 of the lignans had no demonstrable effect at all, despite their known activities in other bioassays.

New cucurbitacin glycosides from Picrorhiza kurrooa.

Abstract: From the roots of Picrorhiza kurrooa Royle and Benth., seven cucurbitacin glycosides have been isolated and structurally elucidated mainly by NMR and mass spectroscopy. Four of them (4, 5, 6, 7) are new and two, the 2-O-glycoside of cucurbitacin B (25-acetoxy-2-beta-glucosyloxy-16,20-dihydroxy-9-methyl-19-norl anosta-5, 23-diene-3,11,22-trione) and the 2-O-glucoside of 23,24 didydrocucurbitacin B (25-acetoxy-2-beta-glucosyloxy-16,20-dihydroxy-9-methyl-19-norl anost-5-ene-3, 11-22-trione) were so far not reported as constituents of this plant. The four new cucurbitacins could be identified as 2-beta-glucosyloxy-3,16,20,25-tetrahydroxy-9-methyl-19-norlanos ta-5, 23-diene-22-one, 2-beta-glucosyloxy-3,16,20,25-tetrahydroxy-9-methyl-19-norlanos t-5-ene-22-one, the 2-O-glucoside of cucurbitacin Q (25-acetoxy-2-beta-glucosyloxy-3,16,20-trihydroxy-9-methyl-19-n orlanosta-5, 23-diene-11,22-dione), and the 2-O-glucoside of deacetoxycucurbitacin B (2-beta-glucosyloxy-16,20-dihydroxy-9-methyl-19-norlanosta-5 , 24-diene-3,11,22-trione).

Possible active components of tan-shen (Salvia miltiorrhiza) for protection of the myocardium against ischemia-induced derangements.

Abstract: Extract of Tan-Shen (Salvia miltiorrhiza, Labiatae), a Chinese traditional crude drug, was reported to show beneficial activity for heart disease. Chemical examination on the extract was performed on the basis of screening for protective action on the ischemic myocardium. Isolated hearts were subjected to hypoxic perfusion for 20 min, followed by 45 min reoxygenation, and the recovery of cardiac contractile force and changes in UV absorbance of the perfusate were examined. Among the components isolated, tanshinone I, cryptotanshinone, and tanshinone VI elicited a significant enhanced recovery of the contractile force upon reoxygenation. This was associated with a decrease in the increase in UV absorbance of the perfusate, suggesting the preservation of ATP metabolites in the myocardium. This, in turn, may enhance the restoration of ATP upon oxygen-replenishment. The results suggest that tanshinone I, cryptotanshinone, and tanshinone VI can protect the myocardium against ischemia-induced derangements.

An ethnopharmacognostic approach to the search for immunomodulators of plant origin.

Abstract: The search for immunomodulating plant constituents through basic and field inquiries into the literature and practices of traditional Indian medicine is treated. The strategy of data collecting proceeds through aspects of an ethnobotanical, an ethnopharmaceutical, an ethnopharmacological, and an ethnomedical nature. In the experimental immunopharmacognostic phase, immunomodulatory compounds are isolated and purified through action-guided fractionation procedures. The results described here refer to activities found on human complement activation and on PMN leucocytes activation. The immunomodulating plant compounds included in this report were isolated from Azadirachta indica bark, Woodfordia fructicosa flowers, Picrorhiza kurroa roots, and Jatropha multifida latex.

Protection of liver microsomal membranes from lipid peroxidation by garlic extract.

Abstract: Garlic extract, the ethanol-soluble fraction of garlic, prevented formation of thiobarbituric-acid-reactive substances and fluorescent substances during lipid peroxidation of rat liver microsomes. Lipid peroxidation increased the fluorescence anisotropy of 1,6-diphenyl-1,3,5-hexatriene labelled to the microsomes while this increase was prevented by the garlic extract. It thus seems probable that the garlic extract serves to maintain membrane fluidity. These effects were dependent on its concentration and particularly prominent on exceeding a certain concentration of garlic extract. These results suggest its possible role of protecting the membranes from lipid peroxidation.

New antihepatotoxic naphtho-pyrone glycosides from the seeds of Cassia tora.

Abstract: Two new naphtho-pyrone glycosides, 9-[(beta-D-glucopyranosyl-(1----6)-O-beta-D-glucopyranosyl)oxy]-10- hydroxy-7-methoxy-3-methyl-1H-naphtho[2,3-c]pyran-1 -one (5) and 6-[(alpha-apiofuranosyl-(1----6)-O-beta-D-glucopyranosyl)oxy]- rubrofusarin (6), together with cassiaside (3) and rubrofusarin-6-beta-gentiobioside (4) were isolated from the seeds of Cassia tora L. Their structures were elucidated on the basis of chemical and spectral data. The naphtho-gamma-pyrone glycosides (3, 4, and 6) were found to have significant hepato-protective effects against galactosamine damage, which were higher than that of silybin from Silybum marianum.

HPLC of S-Alk(en)yl-L-cysteine Derivatives in Garlic including Quantitative Determination of (+)-S-Allyl-L-cysteine Sulfoxide (Alliin).

Abstract: Methods developed for the separation of S-alk(en)yl- L-cysteines and their corresponding (+/-)-sulfoxide isomers by reversed-phase HPLC were applied to the analysis of various garlic samples including fresh garlic, dried extracts, and garlic preparations. Extracts were chromatographed following extraction with 50:50 methanol/water, sample clean-up using Bond Elut C18 or SCX cartridges, and pre-column derivatization with O-phthaldialdehyde/ TERT.-butylthiol.(+)- S-Methyl- L-cysteine sulfoxide and (+)- S-allyl- L-cysteine sulfoxide (alliin) were the only compounds which were identified with certainty. Other sulfur amino acids reported to occur in garlic were absent or were below detection limits under standard chromatographic conditions. Assays for alliin, which is an antibiotic precursor and may be used for standardization of garlic preparations, resulted in great variation between samples: alliin contents were found to range from < 0.1% to 1.15% fresh weight. The accuracy and precision of the assay method, including external calibration of alliin, were evaluated.

An anti-complementary polysaccharide with immunological adjuvant activity from the leaf parenchyma gel of Aloe vera.

Abstract: The aim of the study is to develop new substances with immunomodulatory activity. To this end, extracts from plants used in traditional medicine are used as starting material. This study deals with the mucilagenous leaf-gel of Aloe vera which is well reputed for its therapeutical effect on inflammatory-based disorders. The purification of an aqueous gel-extract guided by inhibition of complement activity in HPS is described. Using anion-exchange and gel permeation chromatography a highly active polysaccharide fraction was isolated, that is present in the gel in various chain lengths. The polysaccharides consist of several monosaccharides of which mannose is dominant. The inhibition is based on alternative pathway activation, resulting in consumption of C3. With respect to their biological activity the polysaccharides inhibit the opsonization of zymosan in HPS and display adjuvant activity on specific antibody production and the induction of delayed type hypersensitivity in mice.

Ergosterol peroxide, an active compound from Inonotus radiatus

Abstract: The anti-tumour activity ofisolated ergosterol peroxide was investigated against Walker 256 carcinosarcoma and MCF-7 breast cancer cell lines in vitro

Flavonol glycosides from Calendula officinalis flowers.

Abstract: Seven flavonol 3- O-glycosides were isolated from the flowers of CALENDULA OFFICINALIS L. Their structures were elucidated as isorhamnetin 3- O-glucoside, rutinoside, neohesperidoside, 2 (G)-rhamnosylrutinoside, quercetin glucoside, neohesperidoside, and 2 (G)-rhamnosylrutinoside by paper and thin layer chromatography, UV, (13)C-NMR, and mass spectroscopy. The interglycosidic linkages of isorhamnetin 3- O-neohesperidoside, 2 (G)-rhamnosylrutinoside, quercetin 3- O-neohesperidoside and structural determination of quercetin 2 (G)-rhamnosylrutinoside are described for the first time in CALENDULA OFFICINALIS.

Antifertility principle of Ruta graveolens.

Abstract: Chloroform extracts of the root, stem and leaf of Ruta graveolens L. showed significant anti-fertility activity in rats when administered intragastrically on days 1-10 post-coitum. Fractionation of the extracts led to the isolation of chalepensin as the active component with some toxicity. Time-dosing experiments demonstrated that chalepensin acts at the early stages of pregnancy. It is not clear at this stage if the anti-fertility effect is a direct manifestation of chalepensin toxicity.

Immunosuppressive Principles of Rehmannia glutinosa var. hueichingensis1.

Abstract: Separation of the immunosuppressive principles from Rehmanniae radix was done by monitoring hemolytic plaque-forming cells (HPFC) inhibitory activity to give two new phenethyl alcohol glycosides: jionosides A1 (4) and B1 (5), along with six known compounds: acetoside, isoacteoside, purpureaside C, echinacoside, and cistanosides A and F.

Proanthocyanidins from Krameria triandra root.

Abstract: Oligomeric proanthocyanidins were isolated from rhatany root (Krameria triandra) and characterised by acid hydrolysis, thiolytic degradation, and spectroscopic methods. They consisted of 2-14 flavanol units with mainly 2,3-cis configuration and with a propelagonidin:procyanidin ratio of 65:35. The predominant interflavan linkage was [4,8]. [4,6]-Bonds were present in the higher oligomers, presumably forming branched chain units. The astringency of the drug was mainly due to proanthocyanidins with degrees of polymerization from 5-10, and these were also the astringent compounds of rhatany tea and tincture. A pharmacological screening of the extract revealed a significant antimicrobial effect.

Chemical properties and anti-complementary activities of polysaccharide fractions from roots and leaves of Panax ginseng.

Abstract: Water-soluble and alkaline-soluble polysaccharide fractions, prepared from roots and leaves of PANAX GINSENG C.A. Meyer, were fractionated into strongly acidic, weakly acidic, and neutral polysaccharide fractions by cetyltrimethyammonium bromide, respectively. The roots contained a larger amount of crude polysaccharides than the leaves. These polysaccharide fractions showed different chemical properties, and it was suggested that the roots mainly contained pectins and glucans whereas the leaves mainly contained pectins and heteroglycans. The three water-soluble polysaccharide fractions from the leaves showed higher anti-complementary activity than all corresponding fractions from the roots. However, the three alkaline-soluble polysaccharide fractions from the leaves showed weak activity. Strongly acidic polysaccharide fractions from either roots or leaves decreased the activity after the treatment with periodate indicating the carbohydrate moiety may contribute to the activity.

Minor iridoid and phenol glycosides of Picrorhiza kurrooa

Abstract: From the roots of PICRORHIZA KURROOA a new iridoid glycoside, 6-feruloylcatalpol has been isolated, along with veronicoside and minecoside and two phenol glucosides, picein and androsin.

Characterization of an Alliin Lyase Preparation from Garlic (Allium sativum).

Abstract: An alliin lyase (EC 4.4.1.4) preparation from garlic, ALLIUM SATIVUM L., has been purified to apparent homogeneity. The purification procedure involved liquid chromatography steps on hydroxylapatite, on an anion exchanger, and on a chromatofocussing medium. The enzyme protein was characterized by a relative molecular mass of 108,000, and was found to consist of two equal subunits. Its isoelectric point was determined to be 4.9. The enzyme appeared rather thermolabile. Simulated gastric-intestinal passage by a modified "half change test" revealed a high acid lability of the active alliinase protein. K (m)-values for different substrates were in the mM range, and activating energies for the cleavage of different substrates could be determined. A maximal specific activity for synthetic alliin in the range of 490 micromoles per min and mg protein could be achieved at 33 degrees C. There are some significant differences in the characterization of the purified protein compared to results previously reported by others on this enzyme.

Effect of Leaf Position and Age on the Essential Oil Quantity and Quality in Lemongrass (Cymbopogon flexuosus)1.

Abstract: The amount and composition of the essential oil of CYMBOPOGON FLEXUOSUS (lemongrass) leaves at different positions in the tiller and at different developmental stages were investigated. The results showed that only young leaves are biogenetically active, and that the leafage and leaf position are important factors for the amount and composition of the essential oil. The results obtained also indicated possible interconversions of the essential oil constituents IN VIVO.

The production of secondary metabolites by plant cells cultivated in bioreactors1.

Abstract: Plant cell cultures are a potential source of pharmaceutically important plant metabolites. In the past few years a lot of success has been achieved in the field of the cultivation of plant cells on a large scale. Special bioreactor systems, such as airlift or drum-type fermentors have been devised for the mass cultivation of plant cells. Classical stirred-tank bioreactors (up to 75000 l volume) have also been used for the cultivation of plant cells and the production of important plant metabolites. Plant cells proliferate much slower than microbial cells. In consequence, the time taken to grow a plant cell suspension from the shake-flask level (300 ml) to the production scale (20,000 l) takes about 3 to 6 weeks. Nevertheless, the cost analyses available show that the production of valuable chemicals by a suitable plant cell culture process could be commercially viable. Plant cells have been grown in batch and repeated batch culture, and single- stage as well as two-stage processes have been developed for the production of secondary metabolites by fermentor-cultured plant cells. There are, however, only few cell culture processes that have attracted industrial attention as yet. Biological rather than technological problems are the main obstacles to a more common use of fermentor-cultured plant cells in industry.

Alkaloid Production by Transformed Root Cultures of Cinchona ledgeriana.

Abstract: Transformed root cultures of CINCHONA LEDGERIANA have been generated by infecting shoots cultured IN VITRO with AGROBACTERIUM RHIZOGENES LBA9402 These root cultures grow axenically in the absence of antibiotics or exogenous plant growth regulators in media containing Gamborg B5 salts at half or full strength with 3% (w/v) sucrose as the carbon source They show a 6- to 8-fold increase in fresh weight in 28 days Transformation has been confirmed by Southern blotting using [ (32)P]-labelled fragments from both the T (L)- and T (R)-DNA of the Ri plasmid The cultures are shown to synthesise a range of quinoline alkaloids, of which quinine, cinchonidine, and quinidine are the major components The level of these alkaloids changes with the age of the cultures, reaching a maximum at about 50 microg/g fresh weight after 45 days In addition, the roots contain quinamine and a number of other, unidentified, indole alkaloids, one of which is the major alkaloid present Only about 1% of the total alkaloid present is released to the medium

Anti-inflammatory activity of 5,7-dimethoxyflavone.

Abstract: The anti-inflammatory activity of 5,7-dimethoxyflavone (5,7-DMF) has been assessed. It was found to possess a comparable effect to aspirin on the rat paw edema model, and it showed no inhibition on cotton pellet-induced granuloma formation. On the rat pleurisy model, 5,7-DMF exhibited an antiexudative effect, interfered with leukocyte migration, and markedly inhibited prostaglandin biosynthesis. In addition, 5,7-DMF caused marked lowering of the rectal temperature of rats. The results obtained from Hippocratic screening revealed that 5,7-DMF possessed a weak CNS depressant activity.