Bernadete Pereira da Silva

An anti-inflammatory and immunomodulatory polysaccharide from Orbignya phalerata.

A polysaccharide, a glucan with mean M(r) of 1.0 x 10(6) (MP1), was isolated from the mesocarp of fruits of Orbignya phalerata. Chemical and spectroscopic studies indicated that MP1 has a highly branched glucan type structure composed of alpha-(1-->4) linked D-glucopyranose residues with (3-->4), (4-->6), and with (3-->6) branching points. MP1 enhanced phagocytosis in vivo and exhibited anti-inflammatory activity.

Flavonol glycosides from Costus spicatus.

Two flavonol diglycosides, tamarixetin 3-O-neohesperidoside, kaempferide 3-O-neohesperidoside and the known quercetin 3-O-neohesperidoside, together with six other known flavonoids were isolated from the leaves of Costus spicatus and their structures were elucidated by a combination of spectroscopic and chemical methods. The flavonol diglycosides were evaluated for inhibitory activity of nitric oxide production by activated macrophages (Fig. 1).

Anti-inflammatory and immunologically active polysaccharides of Periandra mediterranea.

Three polysaccharides, glucans with mean M(r)s of 1.5 x 10(5), 3.6 x 10(4) and 2.1 x 10(4), were isolated from dried roots of Periandra mediterranea by fractionation on Sephacryl S-300 HR and Sephadex G-25. Chemical and spectroscopic studies indicated that they have a highly branched glucan type structure composed of alpha-(1-->4) linked D-glucopyranose residues with both (3-->4) and (4-->6) branching points. The polysaccharides enhance phagocytosis in vivo, and exhibit anti-inflammatory activity.

A new steroidal saponin with antiinflammatory and antiulcerogenic properties from the bulbs of Allium ampeloprasum var. porrum.

A new steroidal saponin was isolated from the bulbs of Allium ampeloprasum var. porrumL. On the basis of chemical evidence, comprehensive spectroscopic analyses and comparison of known compounds, its structure was established as (3β,5α,6β,25R)-6-[(β-D-glucopyranosyl)oxy]-spirostan-3-yl O-β-D-glucopyranosyl-(1→2)-O-[β-D-glucopyranosyl-(1→3)]-β-D-galactopyranoside. Results of the present study indicated that the steroidal saponin showed haemolytic effects in the in vitro assays and demonstrated antiinflammatory activity and gastroprotective property using in vivo models.

Bioactive polysaccharides from Costus spicatus

Abstract Three polysaccharides, glucans with mean M r s of 7.50×10 5 , 4.25×10 5 and 2.15×10 5 , were isolated from fresh stems of Costus spicatus by fractionation on Sephacryl S-300 HR and Sephadex G-25. Chemical and spectroscopic studies indicated that they have a highly branched glucan type structure composed of α-(1→4) linked d -glucopyranose residues with (1→3), (1→6) branching points, and a small amount of (1→6) branching to α-(1→3) linked d -glucopyranose residues. The polysaccharides inhibit capillary permeability and demonstrate phagocytosis stimulating properties.

Odoratin 7-O-β-D-glucopyranoside from Bowdichia virgilioides

An isoflavonoid glucoside, odoratin 7-O-β-D-glucopyranoside, was isolated from the roots of Bowdichia virgilioides and its structure was established by spectroscopic and chemical methods. In vitro tests showed that this compound inhibited both T-lymphocyte and B-lymphocyte proliferation.

A furostanol glycoside from rhizomes of Costus spicatus

A new furostanol glycoside was isolated from the rhizomes of Costus spicatus. Its structure was established as (3 beta,22 alpha,25R)-26-(beta -D-glucopyranosyloxy)-22-methoxyfurost-5-en-3-yl O-D-apio-beta-D-furanosyl-(1-->2)-O-[6-deoxy-alpha-L-mannopyranosy l-(1-->4)]- beta-D-glucopyranoside. The structural identification was performed using detailed analysis of 1H and 13C NMR spectra including 2D NMR spectroscopic techniques (COSY, HETCOR and COLOC) and chemical conversions.

Modulation of sodium pumps by steroidal saponins

Costus spicatus, used in Brazilian traditional medicine to expel kidney stones, contains steroidal saponins with different chemical characteristics. In spite of its popular utilization as potent diuretic, no scientific reports correlate this activity with the chemical constituents of the extract. Therefore, two steroidal saponins (3β,22a,25R)-26-(β-ᴅ-glucopyranosyloxy)-2-methoxyfurost-5-en-3-yl O-ᴅ-apio-β-ᴅ-furanosyl-(1→2)-O-[6-deoxy-α-ʟ-mannopyranosyl- (1→4)]-β-ᴅ-glucopyranoside (1) and (3β,22α,25R)-spirostan-3-yl O-ᴅ-apio-β-ᴅ-furanosyl- (1→2)-O-[6-deoxy-α-ʟ-mannopyranosyl-(1→4)]-β-ᴅ-glucopyranoside (la), were isolated from the rhizomes of this plant and their effects on the Na+-ATPase and (Na++K+)-ATPase activities of the proximal tubule from pig kidney were evaluated. It was observed that 1 and la inhibit specifically the Na+-ATPase activity.

Haemolytic activity and immunological adjuvant effect of a new steroidal saponin from Allium ampeloprasum var. porrum.

A new steroidal saponin was isolated from the bulbs of Allium ampeloprasum L. var. porrum. On the basis of chemical evidence, comprehensive spectroscopic analyses, and comparison with known compounds, its structure was established as (3β,5α,6β,25R)‐3‐{(O‐β‐D‐glucopyranosyl‐(1→3)‐β‐D‐glucopyranosyl‐(1→2)‐O‐[O‐β‐D‐glucopyranosyl‐(1→3)]‐O‐β‐D‐glucopyranosyl‐(1→4)‐β‐D‐galactopyranosyl)oxy}‐6‐hydroxyspirostan‐2‐one (1). Results of the present study indicated that 1 exhibited haemolytic activity in the in vitro assays, and immunological adjuvant activity on the cellular immune response against ovalbumin antigen.

Immunologically active polysaccharides from Centrosema pubescens.

Two polysaccharides with mean M(r)s of 2.0 x 10(6) and 3.75 x 10(5), were isolated from powdered seeds of Centrosema pubescens by fractionation on Sephacryl S-300 HR. Chemical and spectroscopic studies indicated that they have a backbone chain composed of beta-(1-->4)-linked D-galactopyranose residues having branches composed of alpha-(1-->5)-linked L-arabinofuranose residues at position 6 of D-galactose of the backbone chain. The polysaccharides showed reticuloendothelial system-potentiating activity in a carbon clearance test.