Granulation by roller compaction and enteric coated tablet formulation of the extract of the seeds of Glinus lotoides loaded on Aeroperl 300 Pharma.

The purpose of this research was to improve the hygroscopicity and poor flow properties of the crude dry extract of the seeds of Glinus lotoides and improve the disintegration time of the core-tablets for enteric coated formulation thereof. The liquid crude extract of the plant was adsorbed on granulated colloidal silicon dioxide (Aeroperl 300 Pharma) at 30% w/w and the dry extract preparation (DEP) was dry-granulated with roller-compaction using Micro-Pactor. Hygroscopicity, flow property and disintegration time were improved significantly due to the adsorption and granulation processes. Moreover, the DEP does not become mucilaginous even at higher relative humidity levels (above 65%). Oblong tablets (20 x 8.25 mm) containing 947 mg of the granulated DEP (equivalent to the traditional dose), 363 mg of Avicel PH101 and 90 mg of Ac-di-Sol as disintegrant were formulated using an instrumented eccentric tablet machine at 20 kN. The tablets showed a crushing strength of 195 N, a friability of 0.4% and disintegrated within 9 min. The tablets were then enteric coated using polymethacrylate co-polymers (Eudragit L 100-55 and Kollicoat MAE 100P). The coated tablets resisted disintegration or softening in simulated gastric fluid for a minimum of 2 h and disintegrated within 15 min in intestine simulated fluid at pH 6.8. In addition to controlling the release of the active agents, the enteric coating improved the strength and decreased friability of the core-tablets.

Quantitative determination of the group of flavonoids and saponins from the extracts of the seeds of Glinus lotoides and tablet formulation thereof by high-performance liquid chromatography.

The total flavonoids and saponins of the seeds of Glinus lotoides in the crude extracts and tablet formulation thereof were quantified by reversed-phase high-performance liquid chromatographic (RP-HPLC) methods with UV detection. The saponins were analyzed after acid hydrolysis in 3 M HCI at 100 degrees C for 1 h. Vicenin-2 and mollugogenol B were isolated and used as reference substances for the quantification of total flavonoids and saponins, respectively. The identity and purity (> 97%) of the standards were confirmed by spectroscopic (UV, MS, and NMR) and chromatographic (HPLC) methods. The flavonoids and saponins of the crude extract of the seeds and tablet formulation were separated by RP-HPLC (Nucleosil RP-18 column, 250 mm x 4.6 mm) using linear gradient elution systems of acetonitrile-water-0.1 M H3PO4 for flavonoids and methanol-water for saponins. Satisfactory separation of the compounds was obtained in less than 30 and 25 min, for the flavonoids and saponins, respectively. The methods were validated for linearity, repeatability, limits of detection (LOD) and limits of quantification (LOQ). Repeatability (inter- and intra-day, n = 6 and 9, respectively) showed less than 2% relative standard deviation (RSD). The LOD and LOQ were found to be 0.075 and 0.225 mg/mL, respectively, for vicenin-2 and 0.027 and 0.082 mg/100 mL, respectively, for mollugogenol B. The content of flavonoids and saponins of six single tablets was between 95 and 103% for flavonoids and 94-98% for saponins. The validated HPLC methods were employed to standardize a fingerprint of a laboratory produced purified extract, which could be used as a secondary standard for the routine quality control. Accordingly, the purified extract was found to contain 21.3% flavonoids (vicenin-2, 10%) and 25.4% saponins (glinuside G, 14.2%).

In vitro availability of kaempferol glycosides from cream formulations of methanolic extract of the leaves of Melilotus elegans.

In Ethiopian traditional medicine, Melilotus elegans Salzm. ex Ser. (Leguminosae) is used for the treatment of haemorrhoids and lacerated wounds. In view of its wide spread use and proven anti-inflammatory activity, 80% methanolic extract of the leaves was formulated into creams. HPLC/UV and MS studies revealed the presence of flavonoids, of which kaempferol was the major aglycone. Quantitative estimation of kaempferol in the hydrolyzed extract as determined by HPLC/UV was found to be 16.3+/-0.93 microg/mg (n=6, range) of extract. The in vitro release profiles of kaempferol glycosides (quantified as kaempferol equivalent) from the cream formulations in a multilayer membrane system indicated that a lipophilic cream of the extract provides higher release of kaempferol glycosides than hydrophilic and amphiphilic ones. Over a study period of 4h, the lipophilic cream released 66+/-5.70% of kaempferol glycosides, while the hydrophilic and amphiphilic creams resulted in 55+/-2.77 and 38+/-2.30% release, respectively.

Hopane-type saponins from the seeds of Glinus lotoides.

Four new hopane-type saponins, glinusides F, G, H, and I (1-4), and the known succulentoside B (5), as well as the two known flavones 5,7,4'-trihydroxyflavone-6,8-di-C-glucoside (vicenin-2) and 5,7,4'-trihydroxyflavone-8-C-sophoroside (vitexin-2' '-O-glucoside), were isolated from the seeds of Glinus lotoides growing in Ethiopia. On the basis of the spectroscopic data analysis, including 2D NMR and HRESIMS, the new structures were characterized as 3beta-O-beta-D-xylopyranosyl-6alpha-O-beta-D-xylopyranosyl-16beta-O-beta-D-xylopyranosyl-22-hydroxyhopane (1), 3beta-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl-6alpha,16beta-dihydroxy-22-O-alpha-L-rhamnopyranosylhopane (2), 3beta-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl-6alpha-O-beta-D-xylopyranosyl-16beta-hydroxy-22-O-alpha-L-rhamnopyranosylhopane (3), and 3beta-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-d-xylopyranosyl-6alpha-O-beta-D-xylopyranosyl-16beta-O-beta-D-xylopyranosyl-22-hopane (4).