Medicinal flowers. III. Marigold. (1): hypoglycemic, gastric emptying inhibitory, and gastroprotective principles and new oleanane-type triterpene oligoglycosides, calendasaponins A, B, C, and D, from Egyptian Calendula officinalis.

The methanolic extract and its 1-butanol-soluble fraction from the flowers of Calendula officinalis were found to show a hypoglycemic effect, inhibitory activity of gastric emptying, and gastroprotective effect. From the 1-butanol-soluble fraction, four new triterpene oligoglycosides, calendasaponins A, B, C, and D, were isolated, together with eight known saponins, seven known flavonol glycosides, and a known sesquiterpene glucoside. Their structures were elucidated on the basis of chemical and physicochemical evidence. The principal saponin constituents, glycosides A, B, C, D, and F, exhibited potent inhibitory effects on an increase in serum glucose levels in glucose-loaded rats, gastric emptying in mice, and ethanol- and indomethacin-induced gastric lesions in rats. Some structure-activity relationships are discussed.     

Medicinal flowers. XVI. New dammarane-type triterpene tetraglycosides and gastroprotective principles from flower buds of Panax ginseng

The oligoglycoside fraction from the flower buds of Panax ginseng C. A. MEYER (Araliaceae) was found to show protective effects on ethanol-induced gastric mucosal lesions in rats. From the oligoglycoside fraction, new dammarane-type triterpene tetraglycosides, floralginsenosides M, N, O, and P, were isolated together with the major oligoglycosides ginsenoside Rd and Re. The structures of the new floralginsenosides were elucidated on the basis of chemical and physicochemical evidence. Ginsenoside Rd (protopanaxadiol 3,20-O-bisdesmoside) exhibited inhibitory effects on ethanol- and indomethacin-induced gastric mucosal lesions in rats.     

Bioactive saponins and glycosides. XXIII. Triterpene saponins with gastroprotective effect from the seeds of Camellia sinensis--theasaponins E3, E4, E5, E6, and E7

The saponin fraction from the seeds of the tea plant [Camellia sinensis (L.) O. KUNTZE (Theaceae)] was found to exhibit potent protective effects on ethanol- and indomethacin-induced gastric mucosal lesions in rats. Five new triterpene saponins, theasaponins E3 (1), E4 (2), E5 (3), E6 (4), and E7 (5), were isolated together with 11 known saponins from the saponin fraction. The chemical structures of 1-5 were elucidated on the basis of chemical and physicochemical evidence. Among the isolated saponins, theasaponins E1 (6), E2 (7), and E5 (3) and assamsaponin C (10) showed an inhibitory effect on ethanol-induced gastric mucosal lesions at a dose of 5.0 mg/kg, p.o. and their activities were stronger than that of omeplazole. With regard to the structure-activity relationships of theasaponins, the following structural requirements for a protective effect on ethanol-induced gastric lesions were suggested; 1) the 21- and/or 22-acyl groups are essential for the activity, 2) acetylation of the 16-hydroxyl group reduce the activity.     

Bioactive saponins and glycosides. XV. Saponin constituents with gastroprotective effect from the seeds of tea plant, Camellia sinensis L. var. assamica Pierre, cultivated in Sri Lanka: structures of assamsaponins A, B, C, D, and E

The saponin fraction from the seeds of the tea plant, Camellia sinensis L. var. assamica Pierre cultivated in Sri Lanka, was found to show a potent protective effect on gastric mucosal lesions induced by ethanol in rats. Nine new acylated polyhydroxyoleanene-type triterpene oligoglycosides called assamsaponins A-I were isolated from the active saponin fraction together with three known saponins, theasaponin E1 and E2 and camelliasaponin B1. The structures of assamsaponins A-E were elucidated on the basis of chemical and physicochemical evidence. Theasaponin E1 exhibited potent gastroprotective activity.     

Medicinal flowers. XIV. New acylated oleanane-type triterpene oligoglycosides with antiallergic activity from flower buds of chinese tea plant (Camellia sinensis)

The methanolic extract from the flower buds of Chinese tea plant (Camellia sinensis (L.) O. KUNTZE) was found to inhibit release of beta-hexosaminidase from RBL-2H3 cells. From the methanolic extract, six new acylated oleanane-type triterpene oligoglycosides, floratheasaponins D-I, were isolated together with 21 known compounds including floratheasaponins A-C. The chemical structures of floratheasaponins D-I were elucidated on the basis of chemical and physicochemical evidence. The principal constituents, floratheasaponins A-F, were found to show the inhibitory activity on the release of beta-hexosaminidase from RBL-2H3 cells.     

Medicinal flowers. XXXVI.1) Acylated oleanane-type triterpene saponins with inhibitory effects on melanogenesis from the flower buds of Chinese Camellia japonica

Four acylated oleanane-type triterpene oligoglycosides, sanchakasaponins E-H, were isolated from the flower buds of Camellia japonica cultivated in Yunnan province, China, together with four known triterpene oligoglycosides. The chemical structures of the new triterpene oligoglycosides were elucidated on the basis of chemical and physicochemical evidence. The inhibitory effects of the triterpene oligoglycoside constituents on melanogenesis in theophylline-stimulated B16 melanoma 4A5 cells were investigated.     

Medicinal Flowers. XXXII. Structures of oleanane-type triterpene saponins, perennisosides VIII, IX, X, XI, and XII, from the flowers of Bellis perennis

Five new triterpene saponins perennisosides VIII (1), IX (2), X (3), XI (4), and XII (5) were isolated from the MeOH-eluated fraction of the methanolic extract from the flowers of Bellis perennis. The MeOH-eluted fraction of the methanolic extract from the flowers of B. perennis was found to inhibit gastric emptying in olive oil-loaded mice at a dose of 200 mg/kg, per os (p.o.). The stereostructures of 1-5 were elucidated on the basis of chemical and spectroscopic evidence.     

Bioactive saponins and glycosides. XXVII. Structures of new cucurbitane-type triterpene glycosides and antiallergic constituents from Citrullus colocynthis

The methanolic extract from the fruit of Citrullus colocynthis showed an inhibitory effect on ear passive cutaneous anaphylaxis reactions as a type I allergic model in mice. From the methanolic extract, two new cucurbitane-type triterpene glycosides, colocynthosides A and B, were isolated together with 17 known constituents. The structures of colocynthosides A and B were elucidated on the basis of chemical and physicochemical evidence. In addition, the principal cucurbitane-type triterpene glycoside, cucurbitacin E 2-O-beta-D-glucopyranoside, and its aglycon, cucurbitacin E, exhibited the antiallergic activity at a dose of 100 and 1.25 mg/kg, p.o., respectively.     

Gastroprotective potentials of the ethanolic extract of Mukia maderaspatana against indomethacin-induced gastric ulcer in rats

This study investigated the protective effects of the ethanolic extract of Mukia maderaspatana against indomethacin-induced gastric ulcer in rats. Gastric ulceration was induced by single intraperitoneal injection of indomethacin (30 mg/kg b.wt.). M. maderaspatana extract produced significant reduction in gastric mucosal lesions, malondialdehyde and serum tumour necrosis factor-α associated with a significant increase in gastric juice mucin content and gastric mucosal catalase, nitric oxide and prostaglandin E2 levels. The volume and acidity of the gastric juice decreased in pretreated rats. The plant extract was evaluated in the gastric juice of rats, untreated has showed near normal levels in pretreated rats. The M. maderaspatana was able to decrease acidity and increase the mucosal defence in the gastric area, therefore justifying its use as an antiulcerogenic agent. Ranitidine significantly increased pH value and decreased pepsin activity and gastric juice free and total acidity. The anti-ulcer effect was further confirmed histologically.     

Medicinal flowers. XI. Structures of new dammarane-type triterpene diglycosides with hydroperoxide group from flower buds of Panax ginseng

Six new dammarane-type triterpene diglycosides with a hydroperoxide group, floralginsenosides A, B, C, D, E, and F, were isolated from ginseng flower, the flower buds of Panax ginseng C. A. MEYER, together with seven known dammarane-type triterpene oligoglycosides. The structures of new floralginsenosides were elucidated on the basis of chemical and physicochemical evidence.     

Medicinal foodstuffs. XXIII. Structures of new oleanane-type triterpene oligoglycosides, basellasaponins A, B, C, and D, from the fresh aerial parts of Basella rubra L.

Basellasaponins A, B, C, and D, oleanane-type triterpene oligoglycosides having the dioxolane-type substituent, were isolated from the fresh aerial parts of Basella rubra L. together with betavulgaroside I, spinacoside C, and momordins IIb and IIc. The chemical structures of basellasaponins A, B, C, and D were determined from chemical and physicochemical evidence.     

Antidiabetic principles of natural medicines. IV. Aldose reductase and qlpha-glucosidase inhibitors from the roots of Salacia oblonga Wall. (Celastraceae): structure of a new friedelane-type triterpene, kotalagenin 16-acetate

The aqueous methanolic extract of an Indian natural medicine, the roots of Salacia oblonga Wall. (Celastraceae), was found to show inhibitory activity on the increase in serum glucose level in sucrose- and maltose-loaded rats. The water-soluble and ethyl acetate-soluble portions from the aqueous methanolic extract showed inhibitory activities on alpha-glucosidase and aldose reductase, respectively. From the water-soluble portion, potent alpha-glucosidase inhibitors, salacinol and kotalanol, were isolated, together with nine sugar related components, while a new friedelane-type triterpene, kotalagenin 16-acetate, was isolated from the ethyl acetate-soluble portion along with known diterpenes and triterpenes. The structure of kotalagenin 16-acetate was elucidated on the basis of physicochemical evidence. Principal components from this natural medicine were examined in terms of inhibitory activity on aldose reductase, and the diterpene and triterpene constituents, including the new kotalagenin 16-acetate, were found to be responsible components for the inhibitory activity on aldose reductase.     

Medicinal flowers. XXI. Structures of perennisaponins A, B, C, D, E, and F, acylated oleanane-type triterpene oligoglycosides, from the flowers of Bellis perennis

Six new acylated oleanane-type triterpene oligoglycosides, perennisaponins A (1), B (2), C (3), D (4), E (5), and F (6), were isolated from the flowers of Bellis perennis (Daisy flower) together with 14 saponins, nine flavonoids, and two glycosides. The structures of 1-6 were elucidated on the basis of chemical and physicochemical evidence.     

Medicinal Flowers. XXXV. Nor-oleanane-type and acylated oleanane-type triterpene saponins from the flower buds of Chinese Camellia japonica and their inhibitory effects on melanogenesis(1))

The methanolic extract and its 1-butanol-soluble fraction from the flower buds of Camellia japonica, cultivated in Yunnan Province, China, showed inhibitory effects on melanogenesis in theophylline-stimulated B16 melanoma 4A5 cells. From the 1-butanol-soluble fraction, a new 28-nor-oleanane-type and three new oleanane-type triterpene saponins, sanchakasaponins A-D, were isolated together with four known triterpene saponins. Their chemical structures were elucidated on the basis of chemical and physicochemical evidence. The inhibitory effects on melanogenesis in theophylline-stimulated B16 melanoma 4A5 cells and structure-activity relationships of the saponins were investigated.     

Effects of Pithecellobium jiringa ethanol extract against ethanol-induced gastric mucosal injuries in Sprague-Dawley rats

Current anti-gastric ulcer agents have side effects, despite the progression and expansion of advances in treatment. This study aimed to investigate the gastroprotective mechanisms of Pithecellobium jiringa ethanol extract against ethanol-induced gastric mucosal ulcers in rats. For this purpose, Sprague Dawley rats were randomly divided into five groups: Group 1 (normal control) rats were orally administered with vehicle (carboxymethyl cellulose), Group 2 (ulcer control) rats were also orally administered with vehicle. Group 3 (positive control) rats were orally administered with 20 mg/kg omeprazole, Groups 4 and 5 (experimental groups) received ethanol extract of Pithecellobium jiringa ethanol extract at a concentration of 250 and 500 mg/kg, respectively. Sixty minutes later, vehicle was given orally to the normal control group, and absolute ethanol was given orally to the ulcer control, positive control and experimental groups to generate gastric mucosal injury. The rats were sacrificed an hour later. The effect of oral administration of plant extract on ethanol-induced gastric mucosal injury was studied grossly and histology. The level of lipid peroxidation (malondialdehyde-MDA), superoxide dismutase (SOD) and gastric wall mucus were measured from gastric mucosal homogenate. The ulcer control group exhibited severe gastric mucosal injury, and this finding was also confirmed by histology of gastric mucosa which showed severe damage to the gastric mucosa with edema and leucocyte infiltration of the submucosal layer. Pre-treatment with plant extract significantly reduced the formation of ethanol-induced gastric lesions, and gastric wall mucus was significantly preserved. The study also indicated a significant increase in SOD activity in gastric mucosal homogenate, whereas a significant decrease in MDA was observed. Acute toxicity tests did not show any signs of toxicity and mortality up to 5 g/kg. The ulcer protective effect of this plant may possibly be due to its preservation of gastric wall mucus along with increased SOD activity and reduction of oxidative stress (MDA). The extract is non-toxic, even at relatively high concentrations.     

Medicinal foodstuffs. XXII. Structures of oleanane-type triterpene oligoglycosides, pisumsaponins I and II, and kaurane-type diterpene oligoglycosides, pisumosides A and B, from green peas, the immature seeds of Pisum sativum L

Two new oleanane-type triterpene oligoglycosides, pisumsaponins I and II, and two new kaurane-type diterpene oligoglycosides, pisumosides A and B, were isolated from the immature seeds (green peas) of Pisum sativum L. together with soyasaponin I, bersimoside I, dehydrosoyasaponin I, and their 6'-methyl esters. The structures of pisumsaponins and pisumosides were determined on the basis of chemical and physicochemical evidence as 22-O-malonylsoyasapogenol B 3-O-alpha-L-rhamnopyranosyl(1-->2)-beta-D-galactopyranosyl(1-->2)-beta-D-glucopyranosiduronic acid (22-O-malonylsoyasaponin I), sandosapogenol 3-O-alpha-L-rhamnopyranosyl(1-->2)-beta-D-galactopyranosyl(1-->2)-beta-D-glucopyranosiduronic acid, 17-O-beta-D-glucopyranosyl-6beta,7beta,13gamma,17-tetrahydroxy-19-kauranoic acid 19-O-beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranoside, and 6beta,7beta,13beta,17-tetrahydroxy-19-kauranoic acid 19-O-beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranoside, respectively.     

Medicinal flowers. IV. Marigold. (2): Structures of new ionone and sesquiterpene glycosides from Egyptian Calendula officinalis

Following the characterization of hypoglycemic, gastric emptying inhibitory, and gastroprotective principles and the structure elucidation of calendasaponins A, B, C, and D, two new ionone glucosides (officinosides A and B), and two sesquiterpene oligoglycosides (officinosides C and D), were isolated from the flowers of Egyptian Calendula officinalis. The structures of the officinosides were elucidated on the basis of chemical and physicochemical evidence.     

Medicinal plants of Thailand. I structures of rheedeiosides A-D and cis-entadamide A β-D-glucopyranoside from the seed kernels of Entada rheedei

Four new oleanane-type triterpene oligoglycosides, named rheedeiosides A, B, C and D, and one new thioamide glycoside, cis-entadamide A β-D-glucopyranoside, were isolated from the seed kernels of a Thai medicinal plant, Entada rheedei SPRENGEL. The rheedeiosides were found to contain N-acetylglucosamine as a sugar component. Their structures were elucidated based on spectral and chemical evidence.     

Medicinal foodstuffs. XXVII. Saponin constituents of gotu kola (2): structures of new ursane- and oleanane-type triterpene oligoglycosides, centellasaponins B, C, and D, from Centella asiatica cultivated in Sri Lanka

Ursane- and oleanane-type triterpene oligoglycosides, centellasaponins B, C, and D, were isolated from the aerial parts of Centella asiatica (L.) Urban cultivated in Sri Lanka together with madecassoside, asiaticoside, asiaticoside B, and sceffoleoside A. The chemical structures of centellasaponins B, C, and D were determined on the basis of chemical and physicochemical evidence to be madecassic acid 28-O-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranoside, madasiatic acid 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranoside, and 3beta,6beta,23-trihydroxyolean-12-en-28-oic acid 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranoside, respectively.     

Medicinal flowers. XXII. Structures of chakasaponins V and VI, chakanoside I, and chakaflavonoside A from flower buds of Chinese tea plant (Camellia sinensis)

Two acylated oleanane-type triterpene oligoglycosides, chakasaponins V and VI, an aromatic glycoside, chakanoside I, and an acylated flavonol oligoglycoside, chakaflavonoside A, were isolated from the flower buds of Chinese tea plant [Camellia sinensis (L.) O. KUNTZE]. The chemical structures of those new glycosides were elucidated on the basis of chemical and physicochemical evidence.