Perennisosides I-VII, acylated triterpene saponins with antihyperlipidemic activities from the flowers of Bellis perennis

The methanolic extract and its saponin fraction (methanol-eluted fraction) of the flowers of Bellis perennis were found to suppress serum triglyceride elevation in olive oil-treated mice. From the saponin fraction, seven new triterpene saponins, perennisosides I (1), II (2), III (3), IV (4), V (5), VI (6), and VII (7), were isolated together with four known saponins, bellidioside A (8), asterbatanoside D (9), bernardioside B 2 (10), and bellissaponin BS6 (11). The stereostructures of 1- 7 were elucidated on the basis of chemical and spectroscopic evidence. Among these saponins, perennisosides I (1) and II (2) showed inhibitory effects on serum triglyceride elevation at doses of 25-50 mg/kg, po.     

Camelliols A-C, three novel incompletely cyclized triterpene alcohols from sasanqua oil (Camellia sasanqua)

Three novel triterpene alcohols, camelliols A (1), B (3), and C (5), possessing a mono-, bi-, and tricyclic ring system, respectively, have been isolated, along with achilleol A, a known monocyclic triterpene alcohol, from the nonsaponifiable lipids of sasanqua oil (Camellia sasanqua). The structures of these new alcohols were determined on the basis of spectroscopic methods.     

Triterpene saponins with gastroprotective effects from tea seed (the seeds of Camellia sinensis)

Six new triterpene saponins, theasaponins A(1) (1), A(2) (2), A(3) (3), F(1) (4), F(2) (5), and F(3) (6), were isolated from the saponin fraction of the seeds of Camellia sinensis. The stereostructures of 1-6 were elucidated on the basis of chemical and physicochemical evidence. Theasaponin A(2) (2) showed an inhibitory effect on ethanol-induced gastric mucosal lesions in rats at a dose of 5.0 mg/kg, p.o., and its activity was more potent than that of omeplazole. Structure-activity relationships for theasaponins on ethanol-induced gastroprotective activities may be suggested as follows: (1) the 28-acetyl moiety enhances activity; (2) theasaponins having a 23-aldehyde group exhibit more potent activities than those with a 23-hydroxymethyl group or a 23-methoxycarbonyl group.     

Anti-hyperglycemic effect of black tea (Camellia sinensis) in rat

Investigations were carried out to evaluate the effect of the hot water extract of black tea (Camellia sinensis (L.) O. Kuntze (Theaceae) on streptozotocin (STZ)-induced diabetes in rats. The extract significantly reduced the blood glucose level and was found to possess both preventive and curative effects on experimentally produced diabetes in rats. The study reveals that, like green tea, black tea also possesses antidiabetic activity.     

Proconvulsive effect of tea (Camellia sinensis) in mice.

Investigations were carried out to evaluate the effect of acute and chronic administration of both black and green tea on three models of experimentally induced convulsions in mice. Tea extract (both black and green) significantly accelerated the onset of convulsion, increased the duration of convulsion and mortality in mice. Since both the extracts failed to alter the GABA level in brain, based on the earlier report that both black and green tea might act on Ca(2+) channels, it can be suggested that the observed proconvulsive effect of tea is not mediated through GABA but through Ca(2+) channels. Copyright-Copyright 1999 John Wiley & Sons, Ltd.     

Toxicological effects of Camellia sinensis (green tea): A review

Many scientific articles proved that green tea (GT), Camellia sinensis, has a great potential to manage central nervous system, cardiovascular, and metabolic diseases and treat cancer and inflammatory disorders. However, it is important to consider that “natural” is not always “safe.” Some relevant articles reported side effects of GT, detrimental effects on health. The aim of this study is to provide a classified report about the toxicity of GT and its main constituents in acute, subacute, subchronic, and chronic states. Furthermore, it discusses on the cytotoxicity, genotoxicity, mutagenicity, carcinogenicity, and developmental toxicity of GT and its main constituents. The most important side effects have been reported hepatotoxicity and gastrointestinal disorders specially while consumed on an empty stomach. GT and its main components are not major teratogen, mutagen, or carcinogen substances. However, there is limited data in using them during pregnancy, and they should be used with caution in pregnancy, breast‐feeding, and susceptible people. Because GT and its main components have a wide variety of drug interactions, consideration should be taken in coadministration of them with narrow therapeutic indexed drugs. Furthermore, they evoke selective cytotoxicity on cancerous cells that could engage them as an adjuvant substance in cancer therapy.     

Anti-ulcer effect of the hot water extract of black tea (Camellia sinensis)

The effect of the hot water extract of black tea (Camellia sinensis (L.) O. Kuntze, Theaceae) on ulceration induced by various ulcerogens and by cold restraint stress (CRS) was investigated in albino rats. While prior administration of tea extract for 7 days significantly reduced the incidence of ulcer, ulcer number and ulcer index produced by aspirin, indomethacin, ethanol, reserpine and CRS, it failed to inhibit the ulcers induced by serotonin and histamine. Tea extract also favourably altered the changes in acid and peptic activity of gastric secretion induced by aspirin, indomethacin, ethanol, reserpine and CRS. The observations suggest that the hot water extract of black tea possesses anti-ulcer activity, probably mediated through prostaglandins.     

Antidiarrhoeal activity of hot water extract of black tea (Camellia sinensis)

The effect of a hot water extract of black tea (Camellia sinensis (L.) O. Kuntze, Theaceae) on upper gastrointestinal transit and on diarrhoea was investigated employing conventional rodent models of diarrhoea. Black tea extract was found to possess antidiarrhoeal activity in all the models of diarrhoea used. Naloxone (0.5 mg/kg i.p.) significantly inhibited the antidiarrhoeal activity of the extract as well as loperamide, thus indicating a role of the opioid system in the antidiarrhoeal activity of the extract.     

In vitro anti-beta-secretase and dual anti-cholinesterase activities of Camellia sinensis L. (tea) relevant to treatment of dementia

The primary target of licensed drugs for the treatment of Alzheimer's disease is the inhibition of the enzyme acetylcholinesterase, although preventing beta-amyloidosis is a prime target for drugs in development. The in vitro dual anti-cholinesterase and beta-secretase activities of Camellia sinensis L. extract (tea) is reported. Green and black tea inhibited human acetylcholinesterase (AChE) with IC(50) values of 0.03 mg/mL and 0.06 mg/mL respectively, and human butyrylcholinesterase (BuChE) with IC(50) values 0.05 mg/mL. Green tea at a final assay concentration of 0.03 mg/mL inhibited beta-secretase by 38%. These novel findings suggest that tea infusions contain biologically active principles, perhaps acting synergistically, that may be used to retard the progression of the disease assuming that these principles, yet to be identified, reach the brain.     

Cytotoxic acylated triterpene saponins from the husks of Xanthoceras sorbifolia

Four new oleanane-type triterpene saponins, xanifolia-Y0 (1), xanifolia-Y2 (2), xanifolia-Y3 (3), and xanifolia-Y7 (4), were isolated from the husks of Xanthoceras sorbifolia along with two known analogues, xanifolia-Y8 (5) and xanifolia-Y10 (6). The structures of 1-4 were determined by spectroscopic data interpretation and chemical degradation. Compounds 1-6 were evaluated for their cell-growth inhibition activity toward human ovarian cancer cells (OVCAR3) by a MTT assay, and the IC50 values ranged from 4 to 13 microM. On the basis of the results obtained, it is concluded that a C-3 trisaccharide with a galactose and acylation with an angeloyl group at both C-21 and C-22 are important for cell inhibition activity for this class of compounds.     

Oral hypoglycaemic, antihyperglycaemic and antidiabetic activities of Sri Lankan Broken Orange Pekoe Fannings (BOPF) grade black tea (Camellia sinensis L.) in rats

Ethnopharmcological relevance

Sri Lankan traditional practitioners recommend the consumption of black tea infusion (BTI) made from Camellia sinensis L. plant for regulation of glycaemia. However, they do not specify the grade of tea and their origin (i.e., agroclimatic elevation) and as such many prediabetics and milddiabetics use BOPF grade tea.

Aim of the study

This study examines the blood glucose lowering potential of Sri Lankan BOPF grade tea and its potency with respect to agroclimatic elevations.

Materials and methods

Unblended orthodox BOPF grade tea samples were collected from high-, mid- and low-grown agroclimatic elevations in Sri Lanka. Different concentrations of warm BTI (60, 120 and 480 mg/ml), tolbutamide (reference drug: 22.5 mg/kg body weight) and water (control) were orally administered to different groups of rats, and hypoglycaemic and antihyperglycaemic activities were assessed. Antidiabetic activity was determined using streptozotocin induced diabetic rats. Mechanisms of blood glucose lowering actions were investigated using several standards techniques.

Results

BTI exhibited significant (P < 0.05), dose-dependent and marked hypoglycaemic and antihyperglycaemic activities with quick onset. These effects did not differ with respect to agroclimatic elevation, although there were differences in the content of phyto-constituents. BTI also showed marked and quick antidiabetic activity. BTI inhibited intestinal glucose absorption and impaired α-glucosidase and α-amylase activities. BTI possessed insulinomimetic action, ability to improve insulin sensitivity and in vivo antioxidant activity. Notably, BTI was nontoxic.

Conclusions

BTI of Sri Lankan BOPF grade tea has oral hypoglycaemic, antihyperglycaemic and antidiabetic actions which are mediated via multiple mechanisms. This study also indicates that, BOPF grade tea of any agroclimatic elevations in Sri Lanka could be used in the regulation of glycaemia.     

Antiinflammatory and antioxidant property of saponins of tea [Camellia sinensis (L) O. Kuntze] root extract

Two groups of saponins, TS-1 and TS-2, isolated from tea root extract (TRE) were tested for antiinflammatory and in vitro antioxidant activity. Both TS-1 and TS-2 inhibited carrageenan-induced paw oedema in rats. The antioxidant activity of these compounds was evaluated using the xanthine-xanthine oxidase system. The study indicated that the previously observed antitumour activity of TRE might be mediated through scavenging of free radicals by saponins and their antiinflammatory activity.     

The effects of rooibos (Aspalathus linearis), green tea (Camellia sinensis) and commercial rooibos and green tea supplements on epididymal sperm in oxidative stress-induced rats

Reactive oxygen species (ROS) are involved in many physiological functions of mammalian sperm. Numerous endogenous antioxidants belonging to both enzymatic and non‐enzymatic groups can remove excess ROS and prevent oxidative stress (OS). This study compares the modulation of OS by rooibos, Chinese green tea and commercial rooibos and green tea supplements in rat sperm. Male Wistar rats (n = 60) were supplemented with fermented rooibos, ‘green’ rooibos, Chinese green tea, rooibos supplement, green tea supplement or water for 10 weeks while OS was induced during the last 2 weeks. Sperm count and motility were significantly higher for rats consuming fermented rooibos and ‘green’ rooibos when compared with the other groups. Catalase activity was significantly higher in the sperm of rats consuming fermented rooibos, ‘green’ rooibos and both the rooibos and green tea supplements. Superoxide dismutase concentration in the sperm of rats supplemented with fermented rooibos, ‘green’ rooibos and green tea was higher. Sperm glutathione levels of rats consuming the fermented and ‘green’ rooibos were also significantly higher. Rooibos fermented and ‘green’ rooibos showed a tendency to lower the levels of ROS and lipid peroxidation when compared with the control group. In conclusion, both rooibos extracts could offer a measure of protection against induced oxidative damage by increasing the antioxidant defence mechanisms and thereby improving the sperm quality and function. Copyright © 2012 John Wiley & Sons, Ltd.     

Lycopodatines A-C, C(16)N alkaloids from Lycopodium inundatum

Three new alkaloids, lycopodatines A (1), B (2), and C (3), have been isolated from the club moss Lycopodium inundatum, and the structures and absolute configuration were elucidated on the basis of 2D NMR data and chemical transformation.     

Antifertility effect in male rats of oleanolic acid, a triterpene from Eugenia jambolana flowers

The antifertility activity of oleanolic acid (C30H48O3), isolated from the flowers of Eugenia jambolana, was evaluated in male albino rats. The administration of the compound for 60 days decreased the fertilizing capacity of the animals without any significant changes in body weight or reproductive organ weights. The compound produced arrest of spermatogenesis but did not cause any abnormality to spermatogenic cells, Leydig interstitial cells and Sertoli cells. Oleanolic acid may prove to be a promising antifertility agent devoid of undesirable side effects.     

New flavonol oligoglycosides and polyacylated sucroses with inhibitory effects on aldose reductase and platelet aggregation from the flowers of Prunus mume

The methanolic extract from the fresh flowers of Prunus mume exhibited inhibitory effects against aldose reductase and platelet aggregation. From the methanolic extract, two new flavonol oligoglycosides, 2' '-O-acetylrutin and 2' '-O-acetyl-3'-O-methylrutin, and two new polyacylated sucroses, prunoses I and II, were isolated together with 11 known constituents. The structures of 2' '-O-acetylrutin, 2' '-O-acetyl-3'-O-methylrutin, and prunoses I and II were determined on the basis of chemical and physicochemical evidence as quercetin 3-O-alpha-L-rhamnopyranosyl(1-->6)-2' '-O-acetyl-beta-D-glucopyranoside, 3'-O-methylquercetin 3-O-alpha-L-rhamnopyranosyl(1-->6)-2' '-O-acetyl-beta-D-glucopyranoside, 1,4,3',4',6'-penta-O-acetyl-6-O-p-coumaroylsucrose, and 1,3',4',6'-tetra-O-acetyl-6-O-p-coumaroylsucrose, respectively. The flavonol glycosides and prunose I were found to inhibit aldose reductase, while prunoses I and II inhibited platelet aggregation induced by thrombin.     

Safety evaluation of tea (Camellia sinensis (L.) O. Kuntze) flower extract: assessment of mutagenicity, and acute and subchronic toxicity in rats

Ethnopharmacological relevance

Tea (Camellia sinensis (L.) O. Kuntze, Theaceae) flowers possess many physiological functions and have been used in traditional medicines for deodorization, skin care, cough suppressant and expectorant in China. However, there is a little information about its possible toxicity.

Aim of the study

The present investigation was carried out to evaluate the safety of tea flower extract by mutagenicity and acute and subchronic toxicity studies.

Materials and methods

Mutagenicity of tea flower extract was evaluated by the Ames test in Salmonella typhimurium strains TA97, TA98, TA100 and TA102 at concentrations of 0.008, 0.04, 0.2, 1.0, 5.0 mg/plate. In the acute toxicity study, Sprague-Dawley rats were administered a single dose of 12.0 g/kg of body weight by gavage, and were monitored for 14 days. In the subchronic toxicity study, tea flower extract was administered by gavage at doses of 1.0, 2.0 and 4.0 g/kg body weight daily for 13 weeks to Sprague-Dawley rats.

Results

In the Ames test, there was no mutagenic effect of tea flower extract (up to 5.0 mg/plate) towards four tested strains (TA97, TA98, TA100, TA102), with or without metabolic activation (S9). In the acute toxicity study, all animals gained weight and appeared active and normal, so the LD₅₀ value must be >12.0 g/kg body weight. In the subchronic toxicity study, no dose-related effects on survival, growth, hematology, blood chemistry, organ weights, or pathologic lesions were observed.

Conclusion

These results indicate that tea flower extract does not possess mutagenic potential, and that both acute and subchronic toxicity towards animals is very low. A no-observed adverse-effect level (NOAEL) for tea flower extract is 4.0 g/kg bw/day for rats under the conditions of this study.     

Anti-inflammatory, anti-tumor-promoting, and cytotoxic activities of constituents of marigold (Calendula officinalis) flowers

Ten oleanane-type triterpene glycosides, 1-10, including four new compounds, calendulaglycoside A 6'-O-methyl ester (2), calendulaglycoside A 6'-O-n-butyl ester (3), calendulaglycoside B 6'-O-n-butyl ester (5), and calendulaglycoside C 6'-O-n-butyl ester (8), along with five known flavonol glycosides, 11-15, were isolated from the flowers of marigold (Calendula officinalis). Upon evaluation of compounds 1-9 for inhibitory activity against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation (1 microg/ear) in mice, all of the compounds, except for 1, exhibited marked anti-inflammatory activity, with ID50 values of 0.05-0.20 mg per ear. In addition, when 1-15 were evaluated against the Epstein-Barr virus early antigen (EBV-EA) activation induced by TPA, compounds 1-10 exhibited moderate inhibitory effects (IC50 values of 471-487 mol ratio/32 pmol TPA). Furthermore, upon evaluation of the cytotoxic activity against human cancer cell lines in vitro in the NCI Developmental Therapeutics Program, two triterpene glycosides, 9 and 10, exhibited their most potent cytotoxic effects against colon cancer, leukemia, and melanoma cells.     

Gastrointestinal enhancement of MRI with melanin derived from tea leaves (Thea sinensis Linn.).

Melanin was extracted from tea leaves (Thea sinensis Linn.) for the first time. Characterization of melanin proved similarity of the original compound to standard melanin. The Langmuir adsorption isotherms for gadolinium (Gd) binding were obtained using melanin. Melanin-Gd preparation demonstrated low acute toxicity. LD(50) for this preparation was in a range of 1250-1500 mg/kg in mice. Magnetic Resonance Imaging (MRI) properties of melanin itself and melanin-Gd complexes have been estimated. Gd free melanin fractions possess slighter relaxivity compared with its complexes. The relaxivity of lower molecular weight fraction was two times higher than relaxivity of Gd(DTPA) standard. Postcontrast images demonstrate that oral administration of melanin complexes in concentration 0.1 mM provides essential enhancement to longitudinal relaxation times (T(1))-weighted spin echo image. The required contrast and delineation of the stomach wall demonstrated uniform enhancement of MRI with proposed melanin complex.     

Anti-inflammatory activities of the triterpene acids from the resin of Boswellia carteri

Boswellic acids are the main well-known active components of the resin of Boswellia carteri (Burseraceae) and these are still dealing with the ethnomedicinal use for the treatment of rheumatoid arthritis and other inflammatory diseases. Although several studies have already been reported on the pharmacological properties, especially on the anti-inflammatory activity, of Boswellia carteri resin and boswellic acids, the ethnomedicinal importance of Boswellia carteri and its components, boswellic acids, prompted us to undertake detailed investigation on the constituents of the resin and their anti-inflammatory activity. Fifteen triterpene acids, viz., seven of the beta-boswellic acids (ursane-type) (1-7), two of the alpha-boswellic acids (oleanane-type) (8, 9), two of the lupeolic acids (lupane-type) (10, 11), and four of the tirucallane-type (12-14, 16), along with two cembrane-type diterpenes (17, 18), were isolated and identified from the methanol extract of the resin of Boswellia carteri. Upon evaluation of 17 compounds, 1-14 and 16-18, and compound 15, semi-synthesized from 14 by acetylation, for their inhibitory activity against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation (1 microg/ear) in mice, all of the compounds, except for 18, exhibited marked anti-inflammatory activity with a 50% inhibitory dose (ID(50)) of 0.05-0.49 mg/ear.