BACKGROUND:Morin, a bioflavonoid with antioxidant properties, shows intestinal anti-inflammatory activity in the acute phase of the trinitrobenzenesulphonic acid model of rat colitis.AIM:To assess the anti-inflammatory activity of morin in the chronic stages of trinitrobenzenesulphonic acid-induced rat colitis.METHODS:Rats were rendered colitic by a single colonic instillation of 30 mg of the hapten trinitrobenzenesulphonic acid dissolved in 0.25 mL of 50% ethanol. A group of colitic animals was given morin orally at doses of 25 mg/kg daily. Animals were sacrificed every week for 4 weeks. Colonic damage was evaluated macroscopically and microscopically. Different biochemical markers of colonic inflammation were also assayed, including myeloperoxidase activity, leukotriene B4 and interleukin-1beta synthesis, glutathione and malonyldialdehyde levels and nitric oxide synthase activity.RESULTS:The administration of morin facilitated tissue recovery during the 4 weeks following colonic insult with trinitrobenzenesulphonic acid, as demonstrated macroscopically and microscopically, as well as biochemically by a reduction in myeloperoxidase activity. The intestinal anti-inflammatory effect of morin was accompanied by a significant reduction in colonic leukotriene B4 and interleukin-1beta levels, improvement in colonic oxidative stress and inhibition of colonic nitric oxide synthase activity.CONCLUSIONS:Morin exerts a beneficial anti-inflammatory effect in the chronic phase of trinitrobenzenesulphonic acid-induced rat colitis through the down-regulation of some of the mediators involved in the intestinal inflammatory response, including free radicals, cytokines, leukotriene B4 and nitric oxide.

The intestinal anti-inflammatory activity of two flavonoids, hesperidin and diosmin, was evaluated in the acute stage of the trinitrobenzenesulfonic acid (TNBS) model of rat colitis. The results obtained showed that pretreatment with diosmin (10 mg/kg) or hesperidin (10 and 25 mg/kg) reduced colonic damage compared to TNBS control rats. This effect was confirmed biochemically by a reduction in colonic myeloperoxidase activity compared to non-treated colitic animals. Colonic glutathione levels in colitic animals were significantly increased after hesperidin or diosmin treatment. Diosmin decreased colonic MDA production and inhibited LTB4 synthesis, whereas hesperidin failed to do so. Conversely, only hesperidin improved colonic fluid absorption, which was impaired in colitic animals. In conclusion, both diosmin and hesperidin were able to prevent colonic inflammation, acting via a mechanism in which protection against oxidative insult may play a role.

The flavonoid morin was tested for anti-inflammatory activity in trinitrobenzenesulfonic acid (TNBS)-induced rat colitis. Rats were pretreated orally with several doses of the flavonoid (5, 10, 25, 100 and 200 mg/kg) 48, 24 and 1 h before and 24 h after colitis induction and examined for colonic damage 48 h after colitis induction. Colonic inflammation was characterized by diffuse hemorrhagic necrosis of the mucosa, bowel wall thickening, impairment of fluid absorption, increase in myeloperoxidase (MPO) activity, enhanced leukotriene B4 (LTB4) synthesis, glutathione depletion and increased levels of malonyldialdehyde (MDA). Morin treatment, at doses ranging from 10 to 200 mg/kg, significantly reduced colonic macroscopic damage. This beneficial effect was also confirmed by inhibition of colonic MPO activity. Several mechanisms may contribute to the protective effect exerted by morin. First, inhibition of colonic LTB4 synthesis is a common feature for all the active doses of the flavonoid. Second, the antioxidant properties of morin, which partially prevented colonic glutathione depletion (at doses of 10 and 25 mg/kg) or inhibited colonic MDA production (at doses of 100 and 200 mg/kg), can collaborate in preventing TNBS-induced inflammation.

Rutoside, a flavonoid with antioxidant properties, was tested for acute and chronic antiinflammatory activity in trinitrobenzenesulfonic acid-induced rat colitis. Pretreatment with 10 or 25 mg/kg of rutoside by the oral route reduced colonic damage at 2 days. Several mechanisms can be involved in this activity, and one of these may be related to its ability in preventing glutathione depletion of colitic animals, and this could result in mucosal protection against oxidative insult. When rutoside was tested for 1 and 2 weeks after colitis induction, it was able to promote colonic healing. The chronic effect of the flavonoid was also related with its ability to increase colonic glutathione levels and thus reduce the tissue damage derived from intestinal oxidative stress which characterizes inflammatory colitis.

Quercitrin, a flavonoid isolated from Euphorbia hirta, shows antidiarrhoeic activity at doses of 50 mg kg-1, against castor oil- and PGE2-induced diarrhoea in mice, but not when magnesium sulphate is used as a cathartic agent. It also delays rat small intestinal transit if this is accelerated with castor oil. However, the flavonoid does not modify the fluid transport across the colonic mucosa when it is administered intraluminally, either in normal conditions or when this transport is altered by PGE2 or sodium picosulphate. However, quercetin, the aglycone of quercitrin, increases the colonic fluid absorption only in the presence of secretagogue compounds. such as PGE2 and sodium picosulphate. It is concluded that the antidiarrhoeic activity of quercitrin is due to its aglycone, quercetin, which is released by the glycoside in the intestine.

The antidiarrhoeal activity of a procyanidin isolated from the bark of Sclerocarya birrea was studied, using four models of experimentally induced diarrhoea in rats. The cathartic agents used were: magnesium sulphate, castor oil, arachidonic acid and prostaglandin E2. At doses of 150 mg/kg, the procyanidin showed antidiarrhoeal activity in all the models of experimentally induced diarrhoea. The procyanidin (2.5 mug/mL-0.64 mg/mL) dose-dependently inhibited the phasic contractions of the isolated guinea-pig ileum spontaneous activity; this inhibition was significantly reduced by hexamethoniUM (10(-4) M). It also modified the dose-response curves to acetylcholine in a non-competitive way, and relaxed, in a dose-dependent manner, the contractions induced by acetylcholine (10(-7) M) and KCI (50 mm), being five times more potent against acetylcholine. The procyanidin modified the biphasic mechanical response evoked by acetylcholine (10(-7) m) in isolated guinea-pig ileum, inhibiting the phasic response more profoundly than the tonic one. It is concluded that the antidiarrhoeal activity of the procyanidin isolated from S. birrea bark is related to an inhibition in intestinal motility. The way in which it produces this inhibition can be related to an interference with the subsequent events evoked after muscarinic stimulation.

The antidiarrhoeic activity of the Euphorbia hirta whole plant was investigated. The lyophilized decoction demonstrated antidiarrhoeic activity in experimental models of diarrhoea induced by castor oil, arachidonic acid, and prostaglandin E2. It showed no activity when magnesium sulphate was used to provoke the diarrhoea. The lyophilized decoction delayed small intestinal transit when this was accelerated by castor oil but not in normal conditions. A flavonoid, quercitrin, with antidiarrhoeic activity was isolated from this crude drug.

The genus Thymus, a member of the family Lamiaceae, comprises approximately 70–80 species of woody plants and low-lying shrubs. These aromatic species are found in all temperate regions of the northern hemisphere, and are especially common in the Mediterranean area. The large number and diversity of species in this genus have led to its subdivision into sections which, since their inception, have undergone considerable modifications, particularly with respect to the assignment of given species to a section. Currently, the most widely accepted classification is that proposed by Morales (1986), based on the criteria set down by Jalas (1970) and Jalas and Kaleva (1970), who in turn based their work on Velenovski (1906).

The antidiarrhoeic activity of the bark of Sclerocarya birrea was investigated. The lyophilized decoction demonstrated antidiarrhoeic activity in experimental models of diarrhoea induced by magnesium sulphate and sodium picosulphate. This antidiarrhoeic activity was related to an inhibition of intestinal transit rather than to inhibition of net secretion of fluid and electrolytes provoked by the laxative agents. A condensed tannin was isolated from the crude drug which produced inhibition in intestinal motility, and the monomer of which was identified as procyanidin.

The in vitro antibacterial activity of the essential oil obtained from the flowering apex of Thymus serpylloides ssp. gadorensis against various micro-organisms is reported. Moreover, the main chemical groups found in this essential oil are described.

THYMUS SERPYLLOIDES ssp. GADORENSIS is endemic in the Betic region (Spain). Gas chromatography and GC/mass spectrometry studies of its essential oil showed its major components to be carvacrol and its biosynthetic precursors (gamma-terpinene and P-cymene).

AbstractThe hypotensive effects of the alcoholic extract of Thymus orospedanus were investigated in both in vivo and in vitro assays. Our results indicate that the extract reduced rat blood pressure and modified the dose–response curve to epinephrine in the rat vas deferens and the rabbit artery, indicative of a competitive antagonism.

AbstractThe spasmolytic activity of Thymus membranaceus essential oil in the duodenum isolated from rat has been investigated. The qualitative and quantitative composition of the essential oil was studied. The essential oil affects the duodenum in two ways, showing a spasmogenic action (due to 1,8‐cineole) and, on the other hand, an antagonistic non‐competitive effect against the contractions by acetylcholine (due to the phenols and hydrocarbons).

The aerial parts of THYMUS HYEMALIS Lange were collected throughout its complete vegetative cycle (April 1981 to March 1982) from the same locality. The yield and composition of essential oil have been determined in eleven samples with special reference to the content of 1,8-cineole, camphor, thymol, and carvacrol. It was found that the yield and composition of the oil changed from month to month. On the basis of the results obtained, July might be proposed as the most suitable month for harvesting T. HYEMALIS, giving the maximum yield in essential oil, which is especially rich in terpenic hydrocarbons at this time. Maximum levels of 1,8-cineole in August, however, might warrent harvesting during this month as well.

The qualitative and quantitative variations in the essential oil of the OXYODON subspecies of SALVIA LAVANDULIFOLIA Vahl were studied - throughout its complete vegetative cycle (March 1983 to February 1984). Spasmolytic activity of the essential oil was selected as a characteristic warrenting more in depth study. Major components of the essential oil were found to be camphor and 1, 8-cineole, whereas only trace quantities of thujones could be detected at any time in the plant's vegetative cycle. Spasmolytic activity was most intense in May (the flowering period) and lowest in July.

ADVERTISEMENT RETURN TO ISSUEPREVArticleComposition of the Essential Oil in Thymus orospedanusM. E. Crespo, J. Cabo, J. Jimenez, C. Navarro, and A. ZarazueloCite this: J. Nat. Prod. 1986, 49, 3, 558–560Publication Date (Print):May 1, 1986Publication History Published online1 July 2004Published inissue 1 May 1986https://pubs.acs.org/doi/10.1021/np50045a046https://doi.org/10.1021/np50045a046research-articleACS PublicationsRequest reuse permissionsArticle Views95Altmetric-Citations5LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts