Effect of Flavonoid-Rich Extract of Glycyrrhiza glabra on Gut-Friendly Microorganisms, Commercial Probiotic Preparations, and Digestive Enzymes.

Flavonoid-rich extract prepared from Glycyrrhiza glabra has been found to be beneficial in patients with functional dyspepsia and was reported to possess some gut health-promoting properties such as antioxidant, anti-inflammatory and anti-Helicobacter pylori activities. In the present study, the flavonoid-rich extract of Glycyrrhiza glabra was evaluated for its compatibility with probiotic strains (Lactobacillus casei, Lactobacillus fermentum, Lactobacillus plantarum, and Streptococcus thermophilus), commercial probiotic drinks, and digestive enzymes (pancreatic α-amylase, α-glucosidase, phytase, xylanase, and pancreatic lipase). Results of this study indicated that the flavonoid-rich extract of Glycyrrhiza glabra is compatible with the tested probiotic strains, probiotic drinks and digestive enzymes.

'Bacoside B'--the need remains for establishing identity.

Bacopa monnieri is fast gaining popularity for its beneficial effects on cognition and memory. The active constituents of the plant were putatively identified as 'bacosides A and B' in older publications. Subsequently 'bacoside A' was identified as a mixture of four saponins [bacoside A3 (1), bacopaside II (2), bacopasaponin C (3) and the jujobogenin isomer of the latter (4)] and was considered as part of major constituents of the herb along with bacopaside I (5). These major saponins now form part of analytical monographs in many Pharmacopoeia. However identity of 'bacoside B' still appears controversial with seemingly contradictory information available in the scientific literature. At the same time quality of many extracts and herbal products derived from the plant is still being determined based on the content of 'bacosides A and B'. We have elaborated these issues in this article along with our recommendations to move forward towards achieving scientific clarity on the subject.

In vitro anti-Helicobacter pylori activity of a flavonoid rich extract of Glycyrrhiza glabra and its probable mechanisms of action.

ETHNOPHARMACOLOGICAL RELEVANCE: Glycyrrhiza glabra Linn. is regarded useful for peptic ulcer in traditional systems of medicine in India and Helicobacter pylori has been considered as one of the causative factors for peptic ulcer. Aim of the present study is to evaluate the anti-Helicobacter pylori action of GutGard(®), a flavonoid rich extract of Glycyrrhiza glabra and further to elucidate the possible mechanisms of its anti-Helicobacter pylori action. MATERIALS AND METHODS: Agar dilution and microbroth dilution methods were used to determine the minimum inhibitory concentration of GutGard(®) against Helicobacter pylori. Protein synthesis, DNA gyrase, dihydrofolate reductase assays and anti-adhesion assay in human gastric mucosal cell line were performed to understand the mechanisms of anti-Helicobacter pylori activity of GutGard(®). RESULTS: GutGard(®) exhibited anti-Helicobacter pylori activity in both agar dilution and microbroth dilution methods. Glabridin, the major flavonoid present in GutGard(®) exhibited superior activity against Helicobacter pylori while glycyrrhizin did not show activity even at 250 µg/ml concentration. In protein synthesis assay, GutGard(®) showed a significant time dependent inhibition as witnessed by the reduction in (35)S methionine incorporation into Helicobacter pylori ATCC 700392 strain. Additionally, GutGard(®) showed a potent inhibitory effect on DNA gyrase and dihydrofolate reductase with IC(50) value of 4.40 µg/ml and 3.33 µg/ml respectively. However, the extract did not show significant inhibition on the adhesion of Helicobacter pylori to human gastric mucosal cell line at the tested concentrations. CONCLUSION: The present study shows that, GutGard(®) acts against Helicobacter pylori possibly by inhibiting protein synthesis, DNA gyrase and dihydrofolate reductase.

Bioactive caffeic acid esters from Glycyrrhiza glabra.

Thin layer chromatography bioautography (using DPPH spray reagent) guided fractionation of Glycyrrhiza glabra led to the isolation of two caffeic acid derivative esters, viz. eicosanyl caffeate (1) and docosyl caffeate (2). The two compounds exhibited potent elastase inhibitory activity, with IC(50) values of 0.99 microg mL(-1) and 1.4 microg mL(-1) for 1 and 2, respectively. The compounds also showed moderate antioxidant activity in DPPH and ABTS scavenging assays. The results indicate a possible role of caffeic acid derivatives, in addition to flavonoids in the anti-ulcer properties of G. glabra.

Flavonoids and phenol glycosides from Boerhavia diffusa.

Four new compounds were isolated from Boerhavia diffusa namely eupalitin 3-O-beta-D-galactopyranosyl-(1''' --> 2'')-O-beta-D-galactopyranoside (1), 3,3',5-trihydroxy-7-methoxyflavone (4), 4',7-dihydroxy-3'-methylflavone (5) and 3,4-dimethoxyphenyl-1-O-beta-D-apiofuranosyl-(1'' --> 3')-O-beta-D-glucopyranoside (7) along with eight known compounds. The structures were elucidated by analysis of their spectroscopic data.

Constituents of Pterocarpus marsupium: an ayurvedic crude drug.

Five new flavonoid C-glucosides, 6-hydroxy-2-(4-hydroxybenzyl)-benzofuran-7-C-beta-d-glucopyranoside (1), 3-(alpha-methoxy-4-hydroxybenzylidene)-6-hydroxybenzo-2(3H)-furanone-7-C-beta-d-glucopyranoside (2), 2-hydroxy-2-p-hydroxybenzyl-3(2H)-6-hydroxybenzofuranone-7-C-beta-d-glucopyranoside (4), 8-(C-beta-d-glucopyranosyl)-7,3',4'-trihydroxyflavone (5) and 1,2-bis(2,4-dihydroxy,3-C-glucopyranosyl)-ethanedione (6) and two known compounds C-beta-d-glucopyranosyl-2,6-dihydroxyl benzene (7) and sesquiterpene (8), were isolated from an aqueous extract of the heartwood of Pterocarpus marsupium. The structure has been established using spectroscopic data.

Trypsin inhibitory effect of wedelolactone and demethylwedelolactone.

Wedelolactone (WL) and demethylwedelolactone (DWL) isolated from Eclipta alba were tested in the trypsin inhibition bioassay (in vitro). Both compounds showed potent activity. IC(50) values of WL and DWL were found to be 2.9 and 3.0 microg/mL respectively.

Brine shrimp lethality assay of Bacopa monnieri.

Successive petroleum ether, chloroform, ethanol and water extracts, a saponin rich fraction (SRF) and bacoside A isolated from Bacopa monnieri were tested for brine shrimp lethality. Successive ethanol extracts and SRF showed potent activity. Bacoside A showed the maximum activity with a LC(50) of 38.3 microg/mL. The results confirmed the previous reports of an anticancer effect of Bacopa monnieri and suggest bacoside A as the active constituent.