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Showing papers in "Planta Medica in 1994"


Journal ArticleDOI
TL;DR: Three garlic preparations and organosulfur compounds found in aged garlic extract showed radical scavenging activity in both chemiluminescence and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays, indicating that these compounds may play an important role in the antioxidative activity of aged garlic Extract.
Abstract: The antioxidant properties of three garlic preparations and organosulfur compounds in garlic have been determined. Aged garlic extract inhibited the emission of low level chemiluminescence and the early formation of thiobarbituric acid-reactive substances (TBA-RS) in liver microsomal fraction initiated by t-butyl hydroperoxide. However, the water extracts of raw and heat-treated garlic enhanced the emission of low level chemiluminescence. Among the variety of organosulfur compounds, S-allylcysteine (SAC) and S-allylmercaptocysteine (SAMC), the major organosulfur compounds found in aged garlic extract, showed radical scavenging activity in both chemiluminescence and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays, indicating that these compounds may play an important role in the antioxidative activity of aged garlic extract.

426 citations


Journal ArticleDOI
TL;DR: It was shown that propolis inhibits bacterial growth by preventing cell division, thus resulting in the formation of pseudo-multicellular streptococci and the mechanism of action of propolis on bacterial cells is complex and a simple analogy cannot be made to the mode of action.
Abstract: Microcalorimetric and electron microscopic studies on the mode of the antibacterial action of propolis were performed on Streptococcus agalactiae. It was shown that propolis inhibits bacterial growth by preventing cell division, thus resulting in the formation of pseudo-multicellular streptococci. In addition, propolis disorganized the cytoplasm, the cytoplasmic membrane, and the cell wall, caused a partial bacteriolysis, and inhibited protein synthesis. It was evident that the mechanism of action of propolis on bacterial cells is complex and a simple analogy cannot be made to the mode of action of any classic antibiotics.

215 citations


Journal ArticleDOI
TL;DR: The unesterified faradiol, not present in the extract, is the most active of the tested compounds and equals indomethacin in activity, whereas the monools psi-taraxasterol, lupeol, taraxastersol, and beta-amyrin are less active than the free diol.
Abstract: By means of a bioassay-oriented fractionation of the CO2 extract of Calendula flowers, the triterpenoids are shown as the most important anti-inflammatory principles of the drug. Among them, the faradiol monoester appears to be the most relevant principle for the activity of the drug, due to its quantitative prevalence. The unesterified faradiol, not present in the extract, is the most active of the tested compounds and equals indomethacin in activity, whereas the monools psi-taraxasterol, lupeol, taraxasterol, and beta-amyrin are less active than the free diol. The anti-inflammatory activity of different CO2 extracts is proportional to their content of faradiol monoester, which can be taken as a suitable parameter for the quality control of Calendula preparations.

192 citations


Journal ArticleDOI
TL;DR: The results allowed us to establish the relationship between the structure and anti-inflammatory activity on the basis of the different patterns of substitution, particularly hydroxylation, unsaturation, and acylation.
Abstract: Twelve iridoid glycosides have been evaluated for their anti-inflammatory activity on two models: the carrageenan-induced mouse paw edema and the TPA-induced mouse ear edema. Loganic acid was the most active (44.4% edema inhibition) on the former test, whereas the catalpol derivative mixture isolated from Scrophularia, aucubin, verbenalin, and loganin, showed the highest activity (from 72.0 to 80.0% edema inhibition) on the latter. The results allowed us to establish the relationship between the structure and anti-inflammatory activity on the basis of the different patterns of substitution, particularly hydroxylation, unsaturation, and acylation.

177 citations


Journal ArticleDOI
TL;DR: In the presence of ascorbic acid, the level of collagen I secretion was higher for each individual component and for the mixture, and a comparison of asiaticoside and as iatic acid shows that the sugar moiety of the molecule does not seem to be necessary for this biological activity.
Abstract: Asiatic acid, madecassic acid, and asiaticoside, terpenoids with an ursane skeleton, were tested separately and in combination on skin human fibroblast collagen I synthesis in vitro. In the absence of ascorbic acid, the mixture as well as each individual component stimulated collagen I synthesis to a similar extent. In the presence of ascorbic acid, the level of collagen I secretion was higher for each individual component and for the mixture. A comparison of asiaticoside and asiatic acid shows that the sugar moiety of the molecule does not seem to be necessary for this biological activity.

156 citations


Journal ArticleDOI
TL;DR: The pharmacokinetic behavior of S-allylcysteine (SAC), one of the biologically active transformation products from garlic, was investigated after oral administration to rats, mice, and dogs and found that SAC was rapidly and easily absorbed in the gastrointestinal tract and distributed mainly in plasma, liver, and kidney.
Abstract: The pharmacokinetic behavior of S-allylcysteine (SAC), one of the biologically active transformation products from garlic, was investigated after oral administration to rats, mice, and dogs. SAC was rapidly and easily absorbed in the gastrointestinal tract and distributed mainly in plasma, liver, and kidney. The bioavailability was 98.2, 103.0, and 87.2% in rats, mice, and dogs, respectively. SAC was mainly excreted into urine in the N-acetyl form in rats; however, mice excreted both SAC and the N-acetyl form. The half-life of SAC was longer in dogs than in rats and mice.

148 citations



Journal ArticleDOI
TL;DR: Artemisinin and quercetagetin 6,7,3,4'-tetramethyl ether showed significant cytotoxicity against P-388, A-549, HT-29, MCF-7, and KB tumor cells as discussed by the authors.
Abstract: The cytotoxic activity of nine terpenoids and flavonoids isolated from Artemisia annua was tested in vitro on several human tumor cell lines. These compounds are artemisinin, deoxyartemisinin, artemisinic acid, arteannuin-B, stigmasterol, friedelin, friedelan-3 beta-ol, artemetin, and quercetagetin 6,7,3',4'-tetramethyl ether. Friedelane-type triterpenoids were isolated for the first time from this plant. Artemisinin and quercetagetin 6,7,3',4'-tetramethyl ether showed significant cytotoxicity against P-388, A-549, HT-29, MCF-7, and KB tumor cells.

142 citations


Journal ArticleDOI
TL;DR: It is concluded that chamazulene, but not matricine, may contribute to the anti-inflammatory activity of chamomile extracts by inhibiting the leukotriene synthesis and additional antioxidative effects.
Abstract: Matricine and its transformation product chamazulene are constituents of chamomile extracts. Both have been demonstrated to exert anti-inflammatory activity in vivo. Since preparations from chamomile are used for the treatment of inflammatory skin and bowel diseases, we studied the effects of these compounds on the leukotriene production in neutrophilic granulocytes. Chamazulene inhibited the formation of leukotriene B4 in intact cells and in the 105,000 x g supernatant fraction in a concentration-dependent manner. The IC50 values were 15 and 10 microM, respectively. Matricine showed no effect up to 200 microM. Chamazulene (IC50: 2 microM), but not matricine, blocked the chemical peroxidation of arachidonic acid. Additionally, matricine (up to 200 microM) had no effects on the cyclooxygenase and 12-lipoxygenase activities in human platelets. Therefore, it is concluded that chamazulene, but not matricine, may contribute to the anti-inflammatory activity of chamomile extracts by inhibiting the leukotriene synthesis and additional antioxidative effects.

137 citations


Journal ArticleDOI
TL;DR: Polyunsaturated alkamides isolated from Achillea species, Echinacea angustifolia DC, Anacyclus pyrethrum (L.) Link, and Aaronsohnia pubescens were shown to possess inhibitory activity in in vitro cyclooxygenase (sheep seminal microsomes) and 5-lipoxygenases (porcine leukocytes) assays.
Abstract: Polyunsaturated alkamides isolated from Achillea species, Echinacea angustifolia DC., Anacyclus pyrethrum (L.) Link, and Aaronsohnia pubescens (Desf.) Bremer & Humphries, (Compositae) were shown to possess inhibitory activity in in vitro cyclooxygenase (sheep seminal microsomes) and 5-lipoxygenase (porcine leukocytes) assays. Activity appeared to depend on the particular structure of the alkamides.

136 citations


Journal ArticleDOI
TL;DR: In a screening for nematicidal activities in cultures of Basidiomycetes, cultures of Pleurotus pulmonarius and Hericium coralloides exhibited toxic effects towards the saprophytic nematode Caenorhabditis elegans, with the most active compounds being 1 and 2 with LD50 values between 5 and 10 ppm.
Abstract: In a screening for nematicidal activities in cultures of Basidiomycetes, cultures of Pleurotus pulmonarius and Hericium coralloides exhibited toxic effects towards the saprophytic nematode Caenorhabditis elegans. Subsequently S-coriolic acid (1), linoleic acid (2), p-anisaldehyde (3), p-anisyl alcohol (4), 1-(4-methoxyphenyl)-1,2-propanediol (5), and 2-hydroxy-(4'-methoxy)-propiophenone (6) were isolated from submerged cultures of P. pulmonarius. All compounds showed nematicidal activities towards C. elegans. The most active compounds were 1 and 2 with LD50 values between 5 and 10 ppm. Compounds 1, 4, and 5 have not been previously isolated from higher fungi, 6 is a new natural product. From cultures of H. coralloides, which exhibited both repellant and nematicidal effects, a nematicidal fatty acid mixture was obtained, containing linoleic acid, oleic acid, and palmitic acid as its main components.


Journal ArticleDOI
TL;DR: Most of the plant-derived compounds tested showed a positive response in both assays, but with detection limits varying by a factor up to tenfold, it is thus advisable to use both tests, as some activities would otherwise go undetected.
Abstract: The detection limits in two bioautographic assays have been determined for a series of antifungal compounds, including clinically used antimycotics, fungicidal agrochemicals, and various classes of secondary plant metabolites. Target organisms were the filamentous fungus Cladosporium cucumerinum and the yeast Candida albicans. For clinical agents and agrochemicals, the detection limits in the two assays reflected to a certain extent their known spectrum of activity. Most of the plant-derived compounds tested showed a positive response in both assays, but with detection limits varying by a factor up to tenfold. For screening purposes, it is thus advisable to use both tests, as some activities would otherwise go undetected. The MIC values of these substances were determined in order to verify a possible correlation with the detection limit in the bioautographic assays.

Journal ArticleDOI
TL;DR: Interesting antioxidant activities of extracts from different vegetative and reproductive organs of Crataegus monogyna harvested at different stages of growth have been determined by the malondialdehyde-thiobarbituric acid (MDA) test.
Abstract: Interesting antioxidant activities of extracts from different vegetative and reproductive organs of Crataegus monogyna harvested at different stages of growth have been determined by the malondialdehyde-thiobarbituric acid (MDA) test on hepatic microsomal preparations and compared to the contents in total phenolics, proanthocyanidins, catechins, flavonoids, and phenolic acids. The best correlations were established with total phenols while activities in leaves seem to be influenced by flavonoids and in flowers and fruits by proanthocyanidins and catechins.

Journal ArticleDOI
TL;DR: Investigating the effect of the butanol extract of Zizyphus spina-christi leaves as well as christinin-A, its principle saponin glycoside, in normal and streptozotocin-diabetic rats found marked improvement in glucose utilization in diabetic rats in both cases.
Abstract: Zizyphus is one of the plants commonly used in Egyptian folk medicine for the treatment of different diseases. The present study aims to investigate the effect of the butanol extract of Zizyphus spina-christi leaves as well as christinin-A, its principle saponin glycoside, in normal and streptozotocin-diabetic rats. In normal rats, treatment in both cases for one and four weeks produced insignificant changes in all studied parameters. However, in diabetic rats, both treatments significantly reduced serum glucose level, liver phosphorylase and glucose-6-phosphatase (G-6-pase) activities, and significantly increased serum pyruvate level and liver glycogen content after 4 weeks treatment. There was also marked improvement in glucose utilization in diabetic rats in both cases. Serum insulin and pancreatic cAMP levels showed significant increases in diabetic rats treated for a period of 4 weeks with the butanol extract.

Journal ArticleDOI
TL;DR: The antitumour effect of tea plant root extract has been evaluated against Ehrlich ascites carcinoma in Balb-C mice and significant increases of survival times of the TRE-treated, tumour-bearing mice have been confirmed repeatedly with respect to the control group.
Abstract: The antitumour effect of tea plant root extract (TRE) has been evaluated against Ehrlich ascites carcinoma (EAC) in Balb-C mice. Significant increases of survival times of the TRE-treated, tumour-bearing mice have been confirmed repeatedly with respect to the control group. TRE inhibited the tumour cell growth and reversed the changes of haematological parameters consequent to tumour inoculation.

Journal ArticleDOI
TL;DR: These phenolic acids were shown to have a pronounced antibacterial effect against Bacillus cereus, Streptococcus pyogenes, and Mycobacterium fortuitum, and a molluscicidal effect against the snail Biomphalaria glabrata, an intermediate host in the schistosome life cycle.
Abstract: Spondias mombin L. (Anacardiaceae), used in traditional medicine because of its antimicrobial properties, was found to contain a series of 6-alkenyl-salicylic acids. They were isolated from the ethanolic extract of leaves and stems of Spondias mombin by a combination of chromatographic methods. Their structure was determined by NMR and MS techniques as (17:3), (17:2) and (17:1) pelandjuaic acid [or 6-(8'Z,11'Z,14'Z-heptadecatrienyl)-salicylic acid, 6-(8'Z,11'Z-heptadecadienyl)-salicylic acid, and 6-(10'Z-heptadecenyl)-salicylic acid, respectively], 6-(12'Z-non-adecenyl)-salicylic acid, and 6-(15'Z-heneicosenyl)-salicylic acid, the two last compounds being new ones. These phenolic acids were shown to have a pronounced antibacterial effect against Bacillus cereus, Streptococcus pyogenes, and Mycobacterium fortuitum (minimal bactericidal concentration in a concentration range of 3-25 micrograms/ml), and a molluscicidal effect against the snail Biomphalaria glabrata, an intermediate host in the schistosome life cycle. Because of their high molluscicidal activity (LC90 down to 1-3 ppm), these long-chain salicylic acid derivatives may be important tools in the prevention of schistosomiasis.

Journal ArticleDOI
TL;DR: Some phenyl-propanoids with allyl side-chains were found to show the same activity and inhibited the emetic action induced by the oral administration of copper sulfate pentahydrate to leopard and ranid frogs.
Abstract: Magnolol and honokiol, biphenyl compounds, were isolated as anti-emetic principles from the methanolic extract of Magnolia obovata bark. [6]-, [8]-, and [10]-shogaols and [6]-, [8]-, and [10]-gingerols were isolated from the methanolic extract of Zingiber officinale rhizome as anti-emetic principles. Some phenyl-propanoids with allyl side-chains were found to show the same activity. They inhibited the emetic action induced by the oral administration of copper sulfate pentahydrate to leopard and ranid frogs.

Journal ArticleDOI
TL;DR: It is discovered that camptothecin accumulates to approximately 0.4% of the dry weight of young leaves of Camptotheca acuminata, which could provide an easily harvested, non-destructive source of this important drug.
Abstract: Camptothecin is an anticancer and anti-viral alkaloid produced by the Chinese tree Camptotheca acuminata (Nyssaceae). Despite previous reports of low levels of anticancer activity in leaves of Camptotheca acuminata, we have discovered that camptothecin accumulates to approximately 0.4% of the dry weight of young leaves. This level is 1.5-fold higher than that of the seeds and 2.5-fold higher than that of the bark, the two currently used sources of the drug. As the leaves mature, the concentration and absolute amount of camptothecin decreases rapidly. The high levels of camptothecin in young leaves could provide an easily harvested, non-destructive source of this important drug.

Journal ArticleDOI
TL;DR: In the BCG/LPS model, tumor necrosis factor (TNF), a major inflammatory mediator, was increased in serum with a peak at 90-120 min, followed by an increase of serum transaminase activities, suggesting that GPS protected against hepatitis by inhibition of TNF.
Abstract: Gentiopicroside (GPS), a main bitter secoiridoid constituent of roots of Gentiana macrophylla Pall., was tested for therapeutic effects on the two hepatic injury models, the CCl4-induced and lipopolysaccharide (LPS)/bacillus Calmette-Guerin (BCG)-induced hepatitides. An increase in serum level of hepatic aminotransferases (GOT: EC 2.6.1.1. and GPT: EC 2.6.1.2.) induced by a p.o. treatment of CCl4 was suppressed by pretreatment with GPS at 30-60 mg/kg/day for 5 consecutive days. An increase of these enzymes triggered by an i.v. treatment with LPS in mice primed with bacillus Calmette-Guerin (BCG) was also inhibited by GPS pretreatment at the same dose of GPS. In the BCG/LPS model, tumor necrosis factor (TNF), a major inflammatory mediator, was increased in serum with a peak at 90-120 min, followed by an increase of serum transaminase activities. GPS treatment significantly suppressed the increase of TNF in serum at the therapeutic doses, suggesting that GPS protected against hepatitis by inhibiting the production of TNF.

Journal ArticleDOI
TL;DR: Seven labdane-type diterpenoids were isolated from the leaves of Cistus incanus subsp.
Abstract: Seven labdane-type diterpenoids were isolated from the leaves of Cistus incanus subsp. creticus; their structures were established by spectroscopic means. All compounds were tested in vitro for their cytotoxicity against three cell line systems: KB, P-388; and NSCLC-N6. Their antibacterial and antifungal activities were tested against Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosae, Enterobacter cloacae, Escherichia coli, Klebsiella pneumonia, Torulopsis glabrata, Saccharomyces cerevisiae, and Candida albicans as well.

Journal ArticleDOI
TL;DR: Bioassay-guided fractionation of the methanolic extract resulted in isolation of suppressive compounds in the PCA test, and 3',4'-Dimethoxycinnamaldehyde and xanthoxylol potently reduced the contractile response of guinea pig ileal strips to LTD4.
Abstract: The methanolic extract of the roots of Asiasarum sieboldi has been evaluated for anti-allergic effects on various experimental models in vitro and in vivo. Bioassay-guided fractionation of the methanolic extract resulted in isolation of suppressive compounds in the PCA test: methyleugenol (1), elemicin (2), gamma-asarone (3), (-)-asarinin (4), and (-)-sesamin (5). Furthermore, elemicin (2) and (2E,4E,8Z,10E)-N-isobutyl-2,4,8,10-dodecatetraenami de (6) were found to exhibit an inhibitory action on 5-lipoxygenase (5-LOX) from RBL-1 cells. 3',4'-Dimethoxycinnamaldehyde (7) and xanthoxylol (8) potently reduced the contractile response of guinea pig ileal strips to LTD4.

Journal ArticleDOI
TL;DR: Fifteen Compounds, isolated from plants reputed as snake venom antidotes, belonging to different classes of natural products, were shown to protect mice to a significant degree against the lethal action of the venom of BOTHROPS JARARACA snakes.
Abstract: Fifteen compounds, isolated from plants reputed as snake venom antidotes, belonging to different classes of natural products, were shown to protect mice to a significant degree against the lethal action of the venom of Bothrops jararaca snakes. Administration was by the oral route, one hour prior to envenomation. The substances are nitrogen-free, low-molecular-weight compounds for which some kind of biodynamic activity has previously been reported. The fact that they are mostly trivial, naturally-occurring compounds should explain why plants used as snake-bite antidotes are so widely distributed over the plant kingdom.

Journal ArticleDOI
TL;DR: The sap has little effect upon the proliferation of endothelial cells, and no single active ingredient was identified, but several simple phenolic compounds and diterpenes showed a potent anti-bacterial activity.
Abstract: Three in-vitro assays have been adopted to examine the cytotoxicity and anti-bacterial activity of the blood-red sap of Croton lechleri from Ecuador, and to examine its effect upon the proliferation of endothelial cells. The sap was found not to be cytotoxic. Several simple phenolic compounds and diterpenes showed a potent anti-bacterial activity. The sap has little effect upon the proliferation of endothelial cells, and no single active ingredient was identified. A mechanism for the wound-healing property of the sap has been proposed.

Journal ArticleDOI
TL;DR: Lignans are described here for the first time in the family Selaginellaceae for their cytotoxic activity against L 929 murine cells accounts for the use of the plant in traditional Chinese medicine as an anticancer agent.
Abstract: Eleven phenolic Compounds have been isolated from the ethanolic extract of SELAGINELLA DOEDERLEINII by a combination of Chromatographic techniques. These are five lignans: (-)-lirioresinol A, (-)-lirioresinol B, (+)-wikstromol, (-)-nortracheloside, (+)-matairesinol ( 1), two phenylpropanones: 3-hydroxy-1-(3-methoxy-4-hydroxyphenyl)-propan-1-one ( 2), 3-hydroxy-1-(3,5 -dimethoxy-4-hydroxyphenyl)-propan-1-one ( 3), and four biflavonoids: amentoflavone, 7,7''-di- O-methylamentoflavone, 7,4',7'',4'''-tetra- O-methylamentoflavone, and heveaflavone ( 4). Compounds 1, 2, and 3 are novel natural secondary metabolites. Their structures were deduced from their spectral data (mainly (1)H-NMR, mass, and CD). Lignans are described here for the first time in the family Selaginellaceae. Their cytotoxic activity against L 929 murine cells accounts for the use of the plant in traditional Chinese medicine as an anticancer agent.

Journal ArticleDOI
TL;DR: Results suggest that some hydrophobic constituents such as steroids in the stinging nettle roots inhibited the membrane Na+,K(+)-ATPase activity of the prostate, which may subsequently suppress prostate-cell metabolism and growth.
Abstract: The effects of organic-solvent extracts of Urtica dioica (Urticaceae) on the Na+,K(+)-ATPase of the tissue of benign prostatic hyperplasia (BPH) were investigated. The membrane Na+,K(+)-ATPase fraction was prepared from a patient with BPH by a differential centrifugation of the tissue homogenate. The enzyme activity was inhibited by 10(-4)-10(-5) M of ouabain. The hexane extract, the ether extract, the ethyl acetate extract, and the butanol extract of the roots caused 27.6-81.5% inhibition of the enzyme activity at 0.1 mg/ml. In addition, a column extraction of stinging nettle roots using benzene as an eluent afforded efficient enzyme inhibiting activity. Steroidal components in stinging nettle roots, such as stigmast-4-en-3-one, stigmasterol, and campesterol inhibited the enzyme activity by 23.0-67.0% at concentrations ranging from 10(-3)-10(-6) M. These results suggest that some hydrophobic constituents such as steroids in the stinging nettle roots inhibited the membrane Na+,K(+)-ATPase activity of the prostate, which may subsequently suppress prostate-cell metabolism and growth.

Journal ArticleDOI
TL;DR: The administration of the decoction from juniper "berries" to streptozotocin-diabetic rats for 24 days results in a significant reduction both in blood glucose levels and in the mortality index, as well as the prevention of the loss of body weight.
Abstract: This work studies the hypoglycemic activity of a decoction from juniper "berries" (Juniperus communis) both in normoglycemic and in streptozotocin-diabetic animals. Juniper decoction decreases glycemic levels in normoglycemic rats at a dose of 250 mg/kg. This effect can be achieved through: a) an increase of peripheral glucose consumption; b) a potentiation of glucose-induced insulin secretion. The administration of the decoction (125 mg total "berries"/kg) to streptozotocin-diabetic rats for 24 days results in a significant reduction both in blood glucose levels and in the mortality index, as well as the prevention of the loss of body weight. This effect seems to be mediated by the peripheral action of juniper.

Journal ArticleDOI
TL;DR: The antifungal activity of triterpenoid saponins, with hederagenin or oleanolic acid as aglycone, was investigated in vitro by the agar dilution method and alpha-Hederin was the most active compound, and Candida glabrata was themost susceptible strain.
Abstract: The antifungal activity of triterpenoid saponins, with hederagenin or oleanolic acid as aglycone, was investigated in vitro by the agar dilution method. Monodesmosidic hederagenin derivatives were shown to exhibit a broad spectrum of activity against yeast as well as dermatophyte species. alpha-Hederin was the most active compound, and Candida glabrata was the most susceptible strain. The structure-activity relationships are discussed.

Journal ArticleDOI
TL;DR: Of the sesquiterpene lactones tested, helenalin, possessing both the reactive alpha-methylene-gamma-lactone moiety and a reactive alpha,beta-unsubstituted cyclopentenone ring, displayed the strongest cytotoxicity.
Abstract: The cytotoxicity of 21 flavonoids and 5 sesquiterpene lactones, as present in Arnica species, was studied in GLC4, a human small cell lung carcinoma cell line, and in COLO 320, a human colorectal cancer cell line, using the microculture tetrazolium (MTT) assay. Following continuous incubation, most flavonoids showed moderate to low cytotoxicity, as compared with the reference compound cisplatin (IC50 = 1.1 microM against GLC4 and 2.9 microM against COLO 320). Their IC50 values varied from 17 to > 200 microM. The most toxic compound was the flavone jaceosidin. Of the sesquiterpene lactones tested, helenalin, possessing both the reactive alpha-methylene-gamma-lactone moiety and a reactive alpha,beta-unsubstituted cyclopentenone ring, displayed the strongest cytotoxicity. For 2 h exposure, its IC50 value was 0.44 microM against GLC4 and 1.0 microM against COLO 320. COLO 320 was more sensitive than GLC4 for many flavonoids (especially for flavones), but more resistant to the cytotoxic effect of the sesquiterpene lactones bearing an exocylic methylene group fused to the lactone function.

Journal ArticleDOI
TL;DR: The data revealed that reversible sterility could be induced in male rats by papaya seeds aqueous extract treatment without adverse effects on libido and toxicological profile.
Abstract: The influence of the crude aqueous extract of Carica papaya L. (Caricaceae) seeds has been studied on semen profile, fertility, body and organ weight response, and toxicology in male albino rats. The extract was administered at the dose regimens of 10 and 50 mg/animal/day orally for 30, 60, and 90 days and 0.1 and 1.0 mg/animal/day intramuscularly for 15 and 30 days. Cauda epididymal sperm motility and count was reduced significantly at low and high dose regimens both in the oral as well as the intramuscular groups. The reduced sperm motility was associated with morphological defects. Testicular sperm counts were also reduced in all the treatment groups except the low dose intramuscular group. Fertility tests showed dose- and duration-dependent reduction and zero fertility was observed at high dose regimens of the oral and intramuscular groups following 60 and 30 days of treatment, respectively. Testicular weight was reduced in all the treatment groups, whereas accessory sex organs showed a variable response. Body weight and toxicological observations did not show any untoward response. Fertility and all other associated changes returned to normal within 45 and 30 days of treatment cessation in the oral and intramuscular groups, respectively. The data revealed that reversible sterility could be induced in male rats by papaya seeds aqueous extract treatment without adverse effects on libido and toxicological profile.