Millettia dubia De Wild. (Fabaceae): Structural analysis of the oleanane-type glycosides and stimulation of the sweet taste receptors TAS1R2/TAS1R3.

From the root barks of a Central African tree Millettia dubia De Wild. (Fabaceae), ten previously undescribed oleanane-type glycosides were isolated by various chromatographic protocols. Their structures were elucidated by spectroscopic methods, mainly 2D NMR experiments and mass spectrometry, as mono- and bidesmosidic glycosides of mesembryanthemoidigenic acid, hederagenin and oleanolic acid. The stimulation of the sweet taste receptor TAS1R2/TAS1R3 by these glycosides was evaluated, and structure/activity relationships were proposed. Two of them showed an agonist effect on TAS1R2/TAS1R3.

Symplosaponins A-D: New acylated oleanane-type triterpene saponins from Symplocos cochinchinensis and their hepatoprotective effect.

Four new acylated oleanane-type triterpene saponins, symplosaponins A-D (1-4) were successfully isolated from the leaves of Symplocos cochinchinensis (Lour.) S. Moore, alongside with five known compounds (5-9), 2-methoxy-4-prop-1-enylphenyl-1-O-ß-D-apiofuranosyl-(1 â†’ 6)-ß-D-glucopyranoside (5), and 1-[O-ß-d-xylopyranosyl-(1 â†’ 6)-O-ß-d-glucopyranosyl]-2,6-dimethoxy-4-propenyl-phenol (6), 6-O-p-coumaroylsucrose (7), arillatose B (8), and (-)-secoisolariciresinol-O-ß-D-glucopyranoside (9). The structures of these compounds were elucidated through spectroscopic methods, comparison with existing data, and chemical methods. Furthermore, all compounds were assessed for their impact on hepatocellular viability using the Resazurin reduction assay. These investigations aimed to explore the potential hepatoprotective properties of isolated compounds. As a result, 1-[O-ß-d-xylopyranosyl-(1 â†’ 6)-O-ß-d-glucopyranosyl]-2,6-dimethoxy-4-propenyl-phenol (6) and (-)-secoisolariciresinol-O-ß-D-glucopyranoside (9) demonstrated statistically significant hepatoprotective activity in a concentration-dependent manner.

Two new oleanane triterpenes from Maytenus hookeri.

Two new triterpenes mayteneri A (1), mayteneri B (2), and seven known compounds (3-9) were isolated from stems of Maytenus hookeri Loes. The chemical structures of compounds 1 and 2 were established by 1D, 2D NMR, HRESIMS analysis, and calculating electronic circular dichroism (ECD). The structures of known compounds 3-9 were determined by comparison of their spectral with those reported. Compounds 4-7 showed significant inhibitory activity for NLRP3 inflammasome, with the IC50 values of 2.36-3.44 µM.

Pentacyclic triterpenoids as potential ACL inhibitors from the rare medicinal plant Semiliquidambar cathayensis.

An extensive phytochemical investigation on the rare medicinal plant Semiliquidambar cathayensis (family: Hamamelidaceae) led to the isolation of four new (1-4, named semiliquidacids A-D, respectively) and 25 related known pentacyclic triterpenoids. The new structures with absolute configurations were elucidated by spectroscopic methods, electronic circular dichroism (ECD) calculations, and single-crystal X-ray diffraction analysis. Compound 1 represents the first naturally occurring ursane-type triterpenoid featuring an uncommon C-25 formyl group. Compound 4 and oleanolic acid (13) exhibited remarkable inhibitory effects against the ATP-citrate lyase (ACL, an emerging drug target for hyperlipidemia and related metabolic disorders) with IC50 values of 6.5 and 11.9 µM, respectively. The molecular interaction and binding mode between the bioactive triterpenoids and ACL were elaborated by conducting a molecular docking study. Meanwhile, the chemotaxonomic significance of the isolated triterpenoids has been briefly discussed.

Oleanane-Type Triterpene Glycosides from Camellia phanii and Their α-Glucosidase Inhibitory Activity.

Three new oleanane-type triterpene saponins, named camphanosides A-C (1-3), along with five known compounds, chikusetsusaponin IVa (4), spinasaponin A 28-O-glucoside (5), (-)-epicatechin (6), (-)-epicatechin 3-O-gallate (7), and (-)-epigallocatechin 3-O-gallate (8) were isolated from the leaves Camellia phanii Hakoda & Ninh. Their structures were established by 1D and 2D-NMR and mass spectral analysis and chemical methods. Moreover, compounds 1-5 were also evaluated for α-glucosidase inhibitory activity. Compounds 1-3 exhibited moderate α-glucosidase inhibitory activity with IC50 values of 230.7±18.0, 251.4±22.7, and 421.4±25.6 µM, respectively.

Oleanane and 30-noroleanane triterpenoids from the roots of Paeonia lactiflora.

An investigation of EtOAc extract from the roots of Paeonia lactiflora yielded three new 30-noroleanane triterpenoids paeonenoides L-N (1-3) and one new oleanane triterpenoid paeonenoide O (4) together with 7 known compounds (5-11). Extensive spectrographic experiments were applied to identify the structures of 1-4, and their absolute configurations were unambiguously determined by theoretical calculations of ECD spectra, as well as the single-crystal X-ray diffraction analysis. Compounds 8, 9 and 10 were isolated from the Paeonia genus for the first time. Moreover, compounds 8, 9 and 11 showed inhibitory activities against LPS-induced nitric oxide (NO) production in RAW264.7 macrophages with the IC50 values of 72. 17 ± 4.74, 30.02 ± 2.03 and 28.34 ± 1.85 µM, respectively.

Chemometric guided isolation of new triterpenoid saponins as acetylcholinesterase inhibitors from seeds of Achyranthes bidentata Blume.

Achyranthes bidentata Blume (Amaranthaceae) is an annual or perennial herb widely used as ethnomedicine in Traditional Chinese Medicine for treating fever, cold, ulcers, mensural pain, dementia, and osteoporosis. In the current study, UPLC-IM-Q-TOF-MS/MS-based chemometric approach was adopted for the tentative identification of fifty-six compounds in the extract and fractions of A.bidentata seeds. Further, the chemometric-guided isolation led to the isolation of two previously undescribed oleanane-type triterpenoid saponins, named achyranosides A-B (27 and 30), along with three known compounds (31, 44, and 23) from water fraction of A. bidentata seeds. The structures of new compounds were elucidated based on the detailed analysis of NMR, HR-ESI-MS, FT-IR spectral data, and GC-FID techniques. The isolated compounds in vitro acetylcholinesterase inhibitory activity revealed the promising activity of chikusetsusaponin IVa (23) (IC50 = 63.7 µM) with mixed type of AChE inhibition in enzyme kinetic studies. Additionally, in silico binding free energy of isolated compounds disclosed the greater stability of enzyme-ligand complex owing to underlying multiple H-bond interactions. Overall, the study demonstrates the effectiveness of a chemometric-guided approach for the phytochemical exploration and isolation of new oleanane-type triterpenoid saponins from A. bidentata seeds.

A new flavonolignan from milk thistle (Silybum marianum).

A new flavonolignan, sonyamandin (1), along with other known compounds was isolated from the aerial parts and seeds extracts of Silybum marianum (milk thistle) collected from Jordan. The known ones are ursolic acid (2), oleanolic acid (3), maslinic acid (4), oleic acid (5), ß-sitosterol (6), ß-, sitosteryl glucoside (7), apigenin (8), kaempferol-3-O-rhamnoside (9), apigenin-7-O-ß-D-glycoside (10), isosylibin A (11), isosylibin B (12), and silybin B (13). The absolute stereochemistry of 1 was confirmed by 2D NMR and CD analysis.

Effect of bioactive compounds extracted from euphorbious plants on hematological and biochemical parameters of Channa punctatus / Efeito de compostos bioativos extraídos de plantas eufórbicas sobre os parâmetros hematológicos e bioquímicos da Channa punctatus

Channa punctatus was exposed to four different concentrations of Rutin, Taraxerol and Apigenin. Changes in some hematological parameters of Channa punctatus were assessed to determine the influence of these compounds on test fish. Fish were exposed to sublethal concentrations (80 percent of LC50 of 24h) of these compounds for one week. Control fish were also administered for one week. Thereafter, blood samples were obtained from the control and experimental fish. Blood was assayed for selected hematological parameters (hematocrit, hemoglobin, red blood cell count, white blood cell count total plasma protein and plasma glucose concentration). The derived hematological indices of mean corpuscular hemoglobin concentration (MCHC), mean corpuscular hemoglobin (MCH) and mean corpuscular volume (MCV) were calculated. Sublethal concentrations of these compounds caused a dose dependent decrease in hemoglobin values coupled with a decrease in hematocrit values and red blood cell counts are an obvious indication of anemia. The total white blood cell counts and the differential white blood cell counts were decreased except for the lymphocytes, where there was a slight increase. Plasma protein and glucose were also lower in exposed fish when compared with control. The hematological indices MCH, MCHC, MCV were also lowered. The result from this study reveals high mortality rate and deleterious consequences on the health of fish subjected to acute exposure of Rutin, Taraxerol and Apigenin and therefore, should not be used directly in aquaculture without having the proper knowledge.

Channa punctatus foi exposta a quatro diferentes concentrações de Rutina, Taraxerol e Apigenina. Alterações de alguns parâmetros hematológicos da Channa punctatus foram acessados para determinar a influência destes compostos no peixe teste. Peixes foram expostos a concentrações sub-letais (80 por cento 0f LC50 em 24h) destes compostos por uma semana. Os peixes controles foram também expostos durante uma semana. A seguir, amostras de sangue foram obtidas do peixe controle e do experimental. O sangue foi estudado por parâmetros hematológicos selecionados (hematócrito, hemoglobina, contagem de células vermelhas e brancas, proteína plasmática total e concentração de glucose plasmática). Os índices hematológicos derivados da média da concentração corpuscular da hemoglobina (MCHC), a média de hemoglobina corpuscular (MCH) e a média de volume corpuscular (MCV), foram calculados. Concentrações sub-letais destes compostos causaram decréscimo dose-dependente dos valores da hemoglobina unidos a decréscimo de valores de hematócrito e das contagens de células sanguíneas vermelhas o que caracteriza indicação óbvia de anemia. As contagens totais de células brancas e a contagem diferencial destas células estavam diminuídas exceto pelos linfócitos que mostraram leve aumento. A proteína plasmática e a glicose estavam também baixas nos peixes expostos quando comparados com o controle. Os índices hematológicos MCH, MCHC, MCV estavam também diminuídos. Os resultados deste estudo revelam alto percentual de mortalidade e conseqüências deletérias à saúde de peixes submetidos à exposição aguda de Rutina, Talaxerol e Apigenina e portanto eles não devem ser usados diretamente em aquacultura sem conhecimento apropriado.

Studies on the chemical constituents of the roots of Rhododendron molle G. Don / 华中科技大学学报（医学）（英德文版）

The compounds from the root of Rhododendron molle G. Don were isolated, purified by various chromatographic techniques, and their structures were identified according to the physical and chemical features and spectral data. Three compounds were separated from the root of Rhododendron molle G. Don and identified as Rhodojaponin-III, taraxerol, beta-sitosterol for the first time.

Determinación espectrofotometrica de ácido oleanólico y saponinas de quinua (Chenopodium quinoa Willd, variedad Kancolla) / Spectrophotometric determination of oleanolic acid and saponins from quinoa (Chenopodium quinoa Willd, Kancolla variety)

Las saponians de quinua (Chenopodium quinoa Willd., variedad Kancolla) fueron extraídas por reflujo con una mezcla de metanol-agua (4:1). Una vez evaporado el metanol, el residuo remanente fue tratado siguiendo el método de Honerlagen y Tretter con sólo pequeñas modificaciones. Luego, el extracto se sometió a hidrólisis con ácido sulfúrico 12/N en un sistema dioxano-agua (1:1) a 110-C por 15 horas. Las sapogeninas se extrajeron con cloroformo, concentradas, y algunos microlitros (equivalente a 121 mg de quinua) se sembraron contra un estándar de ácido oleanólico sobre placas de silicagel, siendo desarrollado con una mezcla de cloroformo-acetobabenceno (80:20:10; v/v). Las manchas se localizaron con vapores de yodo, y la banda cuyo Rf similar a la del ácido oleanólico, s eseparó e introdujo en una columna de vidrio; eluida con cloroformo, secada y disuelta en 1 ml de ácido acético glacial, fue tratada con 4 ml de una mezcla de ácido sulfúrico - ácido acético glacial (1:1; v/v), calentada en baño maría a 60-C por 25 minutos, enfriada y llevada al espectrofotómetro donde se leyó a 527 mm contra un blanco. Bajo las mismsa condiciones, el ácido oleanólico empleado como estándar mostró una linearidad en el rango de 60 a 480 microgramos. El porcentaje de ácido oleanólico ha sido determinado en quinua (0.269 ñ 0.25) y su contenido de saponinas fue estimado usando un factor de conversión establecido por cromatografía de gas y expresado en la siguiente rlación: % Saponinas = (8.5204) x (% Acido oleanólico). Las sapogneinas estraídas - analizadas por este método - acusaron un error de 10.7% en relación a su determinación por cromatografía de gas