Isolation, structural elucidation of flavonoid constituents fromLeptadenia pyrotechnicaand evaluation of their toxicity and antitumor activity

Abstract

An investigation of Leptadenia pyrotechnica (Forsk.) Decne (Asclepiadaceace) chemical constituents led to the isolation of six flavonoids, kaempferol-3-O-α-l-rhamnopyranosyl (1999→699)-O-β-d-glucopyranoside (E-I.1), kaempferol-3-O-β-d-rhamnopyranosyl (1999→699)-O-β-d-glucopyranoside (E-I.2), texasin-7-O-β-dglucopyranoside E-II.2, kaempferol-3-O-β-d-glucopyranoside (E-III.1), kaempferol (E-IV.1) and kaempferide-3-O-α-l-rhamnopyranosyl (1999→699)-O-β-d-glucopyranoside (E-I.1a). The isolation of these compounds was carried out using Sephadex LH-20 low pressure liquid chromatography (LPLC), preparative paper chromatography (PC), and high performance liquid chromatography (HPLC). The chemical structures of the isolated compounds were established by mass spectrometry (FAB-and EI-techniques), nuclear magnetic resonance NMR (1 H-, 13 C-and COSY) spectral data and ultraviolet (UV) spectroscopic techniques. The acute toxicity of total alcoholic and total flavonoid extracts were examined by brine shrimp. The LC 50 values were 11.89 and 84.14 ppm for the total alcoholic and total flavonoid extracts, respectively. The mortality rates of the isolated flavonoid fractions of E-I, E-I.1, E-I.2 represent the higher percentages of mortality compared with the rest of the flavonoid fractions. The plant exhibited activity as an antitumor agent in the initial potato disc screen.

Antioxidant, Anti-Glycation and Anti-Inflammatory Activities of Phenolic Constituents from Cordia sinensis

“…Further pharmacological screening of this fraction revealed potent antioxidant activity. In this paper we report the isolation of nine known compounds isolated for the first time from this plant: protocatechuic acid ( 1 ) [9], trans -caffeic acid ( 2 ) [10], methyl rosmarinate ( 3 ) [11], rosmarinic acid ( 4 ) [11], kaempferide-3- O - β -D-glucopyranoside ( 5 ) [12], kaempferol-3- O - β -D-glucopyranoside ( 6 ) [13], quercetin-3- O - β -D-glucopyranoside ( 7 ) [14], kaempferide-3- O -α-L-rhamnopyranosyl (1→6)- β -D-glucopyranoside ( 8 ) [13] and kaempferol-3- O -α-L-rhamnopyranosyl (1→6)- β -D-glucopyranoside ( 9 ) [13] (Figure 1). This study was undertaken to investigate the antioxidant potential of these compounds using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity assay.…”

Sephadex® LH-20, Isolation, and Purification of Flavonoids from Plant Species: A Comprehensive Review

“…Three other flavones have also been isolated by SLH: texasin 7- O -β- d -glucopyranoside ( 90 ) from ethyl acetate extract of Leptadenia pyrotechnica aerial part [ 67 ], tilianin ( 91 ) from hydroethanolic (95%) extract of Avena sativa bran (eluent: methanol) [ 64 ], and 5-hydroxy-6,7,3′,4′-tetramethoxyflavone ( 92 ) from flower chloroform extract of Citrus aurantium (eluent: chloroform‒methanol 1:1) [ 68 ].…”

“…This valuable compound has been isolated from 11 different plant species by employing SLH as the last chromatographic step. Ethyl acetate extracts might be considered as the richest fractions in kaempferol ( 130 ) content: from Fragaria ananassa calyx (eluent: acetone‒water 2:1) [ 74 ], Gynura divaricate leaf (eluent: chloroform‒methanol 1:1) [ 75 ], Gingko biloba leaf (eluent: methanol) [ 36 ], Chionanthus retusus flower (eluent: methanol‒water 7:3) [ 24 ], Populus davidiana wood (methanol‒water 3:1, 1:1, 1:3) [ 15 ], and Leptadenia pyrotechnica aerial parts [ 67 ]. Kaempferol ( 130 ) has been furtherly isolated from hydro-methanolic (70%) extracts of Albizia amara leaf [ 83 ] and Allium porrum aerial part [ 84 ] eluting with methanol and methanol‒water (8:2), respectively.…”

Floristic Account of the Asclepiadaceous Species from the Flora of Dera Ismail Khan District, KPK, Pakistan

“…Distribution: India, Pakistan, Arabia and Egypt. Uses: The leaves and bark of the plant are used in folk medicine to prepare antispasmodic, anti-inflammatory, antihistaminic, anti-bacterial diuretic, urolith expulsion, expectorant, gout, and rheumatism remedies [12]. Latxe of branches to is applied tumours and swellings.…”