Medicinal foodstuffs. XIX. Absolute stereostructures of canavalioside, a new Ent-kaurane-type diterpene glycoside, and gladiatosides A1, A2, A3, B1, B2, B3, C1, and C2, new acylated flavonol glycosides, from sword bean, the seeds of Canavalia gladiata

Transcriptome and metabolome changes induced by bitter melon (Momordica charantia)- intake in a high-fat diet induced obesity model

Background and aim

Metabolic syndrome (MetS) is a complex disease of physiological imbalances interrelated to abnormal metabolic conditions, such as abdominal obesity, type II diabetes, dyslipidemia and hypertension. In the present pilot study, we investigated the nutraceutical bitter melon (Momordica charantia L) -intake induced transcriptome and metabolome changes and the converging metabolic signaling networks underpinning its inhibitory effects against MetS-associated risk factors.

Experimental procedure

Metabolic effects of lyophilized bitter melon juice (BMJ) extract (oral gavage 200 mg/kg/body weight-daily for 40 days) intake were evaluated in diet-induced obese C57BL/6J male mice [fed-high fat diet (HFD), 60 kcal% fat]. Changes in a) serum levels of biochemical parameters, b) gene expression in the hepatic transcriptome (microarray analysis using Affymetrix Mouse Exon 1.0 ST arrays), and c) metabolite abundance levels in lipid-phase plasma [liquid chromatography mass spectrometry (LC-MS)-based metabolomics] after BMJ intervention were assessed.

Results and conclusion

BMJ-mediated changes showed a positive trend towards enhanced glucose homeostasis, vitamin D metabolism and suppression of glycerophospholipid metabolism. In the liver, nuclear peroxisome proliferator-activated receptor (PPAR) and circadian rhythm signaling, as well as bile acid biosynthesis and glycogen metabolism targets were modulated by BMJ (p < 0.05). Thus, our in-depth transcriptomics and metabolomics analysis suggests that BMJ-intake lowers susceptibility to the onset of high-fat diet associated MetS risk factors partly through modulation of PPAR signaling and its downstream targets in circadian rhythm processes to prevent excessive lipogenesis, maintain glucose homeostasis and modify immune responses signaling.

Roasting and Cryogenic Grinding Enhance the Antioxidant Property of Sword Beans (Canavalia gladiata)

The objective of this study was to optimize the conditions for enhancing the antioxidant properties of sword bean (Canavalia gladiata) as a coffee substitute in two processing methods, roasting and grinding. The optimum conditions for removing off-flavor of the bean and maximizing functionality and efficiency were light roasting and cryogenic grinding (< 53 μm). In these conditions, extraction yield was 16.75%, total phenolic content (TPC) was 69.82 ± 0.35 mg gallic acid equivalents/g, and total flavonoid content (TFC) was 168.81 ± 1.64 mg quercetin equivalents/100 g. The antioxidant properties were 77.58 ± 0.27% for DPPH radical scavenging activity and 58.02 ± 0.76 mg Trolox equivalents/g for ABTS radical scavenging activity. The values for TFC and ABTS radical scavenging activity were significantly higher (p < 0.05) than in other conditions, and TPC and DPPH radical scavenging activity were second highest in lightly roasted beans, following raw beans. HS-SPME/GCMS analysis confirmed that the amino acids and carbohydrates, which are the main components of sword bean, were condensed into other volatile flavor compounds, such as derivatives of furan, pyrazine, and pyrrole during roasting. Roasted and cryogenically ground (cryo-ground) sword beans showed higher functionality in terms of TFC, DPPH, and ABTS radical scavenging activities compared to those of coffee. Overall results showed that light roasting and cryogenic grinding are the most suitable processing conditions for enhancing the bioactivity of sword beans.

New caryophyllene-type sesquiterpene and flavonol tetraglycoside with sixteen known compounds from sword bean (Canavalia gladiata)

Eighteen compounds including new caryophyllene-type sesquiterpene and flavonol tetraglycoside were purified and isolated from sword beans (Canavalia gladiata). Two new compounds, (Z,1R,7S,9S)-7-hydroxy-11,11-dimethyl-8-methylenebicyclo[7.2.0]undec-4-ene-4-carboxylic acid (2) and kaempferol-7-O-α-l-dirhamnopyranosyl(1 → 2;1 → 6)-O-β-d-glucopyranosyl(1 → 2)-O-α-l-rhamnopyranoside (9), were identified. Other known compounds including methyl gallate (1), (2S,3S,4E,8E)-2-aminooctadeca-4,8-diene-1,3-diol 1-O-β-d-glucopyranoside (3), (2S,3S,4E,8Z)-2-aminooctadeca-4,8-diene-1,3-diol 1-O-β-d-glucopyranoside (4), lupeol (5), trilinolein (6), 1,6-di-O-galloyl β-d-glucopyranoside (7), N-(2-methoxybenzoyl)homoserine (8), dihydrophaseic acid (10), dillenetin (11), kaempferol-7-O-[2-O-β-d-glucopyranosyl-6-O-α-l-rhamnopyranosyl]-α-l-rhamnopyranoside (12), canavalioside (13), kaempferol-3-O-[2-O-β-d-glucopyranosyl-6-O-α-l-rhamnopyranosyl]-β-d-glucopyranoside (14), kaempferol-3-O-(2,6-O-α-l-dirhamnopyranosyl)-β-d-glucopyranoside (15), kaempferol-3-O-rutinoside (16), gladiatoside A₁ (17), and gladiatoside B₁ (18) were identified. The chemical structures of these compounds were determined by ESI-MS and NMR analyses.

Edible Sword Bean Extract Induces Apoptosis in Cancer Cells In Vitro and Inhibits Ascites and Solid Tumor Development In Vivo

Antitumor potential of edible sword bean (Canavalia gladiata (L.)) extract has been evaluated against Daltons lymphoma ascites (DLA) using in vitro and in vivo studies. Methanolic extraction was carried out and in vitro studies were performed against both DLA and A549, lung cancer cell lines. The results revealed that sword bean extract inhibited cell growth and induced apoptosis as evidenced by cytotoxic assay, Hoechst 33342 staining and acridine orange/ethidium bromide dual staining. In vivo studies performed on DLA induced solid as well as ascitic tumors models showed administration of sword bean extract (10 mg/kg B.wt.) could significantly inhibit ascitic and solid tumor development in mice. Therefore, our overall results revealed that C. gladiata treatment could significantly inhibit tumor development and induce apoptosis in tumor cells.

Identification and Characterization of a-Glucosidase Inhibition Flavonol Glycosides from Jack Bean (Canavalia ensiformis (L.) DC

Although the intake of jack bean (Canavalia ensiformis (L.) DC.), an underutilized tropical legume, can potentially decrease the risk of several chronic diseases, not much effort has been directed at profiling the polyphenolics contained therein. Hence, this work aimed to identify and quantify the dominant jack bean polyphenolics, which are believed to have antioxidant and other bioactivities. Four major compounds were detected and identified as kaempferol glycosides with three or four glycoside units. Their structures were established based on UV-visible, 1D, 2D NMR, and HR-ESI-MS analyses. Specifically, kaempferol 3-O-α-l-rhamnopyranosyl (1→6)- β-d-glucopyranosyl (1→2)-β-d-galactopyranosyl-7-O-[3-O-o-anisoyl]-α-l-rhamnopyranoside was detected for the first time, while the other three compounds have already been described in plants other than jack bean. This new compound was found to have a higher α-glucosidase inhibition activity compared to acarbose.

New Diterpenes from Arenga pinnata (Wurmb.) Merr. Fruits

Three new ent-kauran-type diterpenes (1⁻3), named arenterpenoids A⁻C, and five known ones (4⁻8) were isolated and identified from Arenga pinnata (Wurmb.) Merr. Fruits. The structures of these compounds were established by 1D and 2D NMR spectra and HR-ESI-MS. To the best of our knowledge, this is the first scientific report of diterpenes from Arenga genus.

Hippophins C-F, four new flavonoids, acylated with one monoterpenic acid from the seed residue of Hippophae rhamnoides subsp. sinensis

Four new flavonol glycosides (1-4), hippophins C-F, together with one known flavonoid (5), were isolated from the seed residue of Hippophae rhamnoides subsp. sinensis. The chemical structures of these compounds were characterized by 1D and 2D NMR, and HR-ESI-MS data. This report is a continuous research work on the systematic chemical investigation of plants of the genus Hippophae in our laboratory.

Three new flavonoids from the seeds of Hippophae rhamnoides subsp. sinensis

To study the chemical constituents of the seeds of Hippophae rhamnoides subsp. sinensis, three new flavonoids acylated with one monoterpenic acid, named 3-O-β-D-glucosyl-kaempferol-7-O-{2-O-[2(E)-2,6-dimethyl-6-hydroxy-2,7-octadienoyl]}-α-L-rhamnoside (3), 3-O-β-D-sophorosyl-kaempferol-7-O-{3-O-[2(E)-2,6-dimethyl-6-hydroxy-2,7-octadienoyl]}-α-L-rhamnoside (4), and 3-O-β-D-sophorosyl-kaempferol-7-O-{2-O-[2(E)-2,6-dimethyl-6-hydroxy-2,7-octadienoyl]}-α-L-rhamnoside (5), together with four known compounds, were isolated from the seeds of H. rhamnoides subsp. sinensis. Compounds 1 and 2 are reported for the first time from this genus. Their structures were elucidated on the basis of chemical and spectral analysis, including 1D and 2D NMR and HR-MS, and by comparison with literature data.

Bioactive constituents from chinese natural medicines. XXIV. Hypoglycemic effects of Sinocrassula indica in sugar-loaded rats and genetically diabetic KK-A(y) mice and structures of new acylated flavonol glycosides, sinocrassosides A(1), A(2), B(1), and B(2)

The methanolic extract from the whole plant of Sinocrassula indica (Crassulaceae) was found to inhibit the increase in serum glucose levels in oral administration of sucrose and glucose in rats at a dose of 250 mg/kg (p.o.). However, the extract did not inhibit the increase in serum glucose levels after intraperitoneal administration of glucose in these animals but did partly inhibit the gastric emptying. On the other hand, this extract significantly inhibited the increase in serum glucose levels after administration for 2 weeks in KK-A(y) mice, a genetically type II diabetic mice, at a dose of 250 mg/kg/d (p.o.) without significant changes of the weights of body, liver, and visceral fat. From the extract, four new acylated flavonol glycosides, sinocrassosides A(1), A(2), B(1), and B(2), were isolated together with 11 flavonoids and 2 megastigmanes. The absolute stereostructures of the four new compounds were elucidated on the basis of chemical and physicochemical evidence.

Tricalysiosides H-O: Ent-kaurane glucosides from the leaves of Tricalysia dubia

Eight ent-kaurane glucosides, named tricalysiosides H-O, were isolated from Tricalysia dubia. Tricalysioside H possessed a hydroxyl group at the 1-position, to which the glucose moiety was attached. The structure was first elucidated by means of spectroscopic data analysis and finally confirmed by X-ray crystallography. Since acid hydrolysis of 1 gave D-glucose, the aglycone was proved to have an enantio-kaurane type skeleton. The structures of tricalysiosides I-O were mainly elucidated from analysis of spectroscopic evidence.

Medicinal foodstuffs. XXVIII. Inhibitors of nitric oxide production and new sesquiterpenes, zedoarofuran, 4-epicurcumenol, neocurcumenol, gajutsulactones A and B, and zedoarolides A and B, from Zedoariae Rhizoma

A new eudesmane-type sesquiterpene, zedoarofuran, and six new guaiane- or seco-guaiane-type sesquiterpenes, 4-epicurcumenol, neocurcumenol, gajutsulactones A and B, and zedoarolides A and B, were isolated from aqueous acetone extract of Zedoariae Rhizoma together with 36 known sesquiterpenes and two diarylheptanoids. Their stereostructures were elucidated on the basis of chemical and physicochemical evidence. The effects of isolated components on nitric oxide production in lipopolysaccharide-activated mouse peritoneal macrophages were examined and 16 sesquiterpenes including gajutsulactones A and B, and bis(4-hydroxycinnamoyl)methane were found to show inhibitory activity.

Bioactive saponins and glycosides. XIX. Notoginseng (3): immunological adjuvant activity of notoginsenosides and related saponins: structures of notoginsenosides-L, -M, and -N from the roots of Panax notoginseng (Burk.) F. H. Chen

New dammarane-type triterpene saponins, notoginsenosides-L, -M, and -N, were isolated from the glycosidic fraction of the dried roots of Panax notoginseng (Burk.) F. H. Chen. Their structures were elucidated on the basis of chemical and physicochemical evidence. Immunological adjuvant activities of the principal notoginsenosides and related dammarane-type triterpene saponins were examined and notoginsenosides-D, -G, -H, and -K were found to increase the serum IgG level in mice sensitized with ovalbumin.

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 foodstuffs. XXV. Hepatoprotective principle and structures of ionone glucoside, phenethyl glycoside, and flavonol oligoglycosides from young seedpods of garden peas, Pisum sativum L

A new ionone glucoside, pisumionoside, a phenethyl glycoside, sayaendoside, and two acylated flavonol oligoglycosides, pisumflavonosides I and II, were isolated from the young seedpods of garden peas, Pisum sativum L., together with quercetin and kaempferol 3-O-(6-O-trans-p-coumaroyl)-beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosides and quercetin and kaempferol 3-sophorotriosides. The structures of pisumionoside, sayaendoside, and pisumflavonosides I and II were determined on the basis of chemical and physicochemical evidence, respectively. Quercetin 3-sophorotrioside, a principle component, was found to show protective effects on liver injury induced by D-galactosamine and lipopolysaccharide and by carbon tetrachloride in mice.

Bioactive saponins and glycosides. XVIII. Nortriterpene and triterpene oligoglycosides from the fresh leaves of Euptelea polyandra Sieb. et Zucc. (2): Structures of eupteleasaponins VI, VI acetate, VII, VIII, IX, X, XI, and XII

Following the elucidation of eupteleasaponins I, II, III, IV, V, and V acetate, eupteleasaponins VI, VI acetate, VII, VIII, IX, X, XI, and XII were isolated from the fresh leaves of Euptelea polyandra Sieb. et Zucc. The structures of eupteleasaponins VI-XII were determined 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.

Hepatoprotective constituents from Zedoariae Rhizoma: absolute stereostructures of three new carabrane-type sesquiterpenes, curcumenolactones A, B, and C

New carabrane-type sesquiterpene lactones, curcumenolactones A, B, and C, were isolated from the 80% aqueous acetone extract of Zedoariae Rhizoma (Zingiberaceae), together with 41 sesquiterpenes and two diarylheptanoids. The absolute stereostructures of curcumenolactones A, B, and C were determined on the basis of physicochemical evidence, which included nuclear Overhauser effect (NOE) and circular dichroic (CD) spectroscopic analyses. Curcumenone, a principal carabrane-type sesquiterpene from Zedoariae Rhizoma, was found to show potent protective effect on D-galactosamine/lipopolysaccharide-induced acute liver injury in mice. In addition, curcumenolactones A and B and the other constituents showed protective effect on D-galactosamine-induced cytotoxicity in primary cultured rat hepatocytes.

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.