A new flavonostilbene glycoside from roots of Polygonum multiflorum / 中国中药杂志

Polygonflavanol B(1), a new flavonostilbene glycoside, was isolated from the roots of Polygonum multiforum(Polygonaceae) by various column chromatography methods including macroporous resin HP-20, silica gel, Sephadex LH-20, and preparative HPLC. The structure with absolute configuration of the new compound was identified by its physicochemical properties, spectroscopic data, ECD calculation, and chemical method.

Antibacterial activity of 3, 3', 4'-Trihydroxyflavone from Justicia wynaadensis against diabetic wound and urinary tract infection

ABSTRACT The present investigation was designed to study the effect of an active compound isolated from Justicia wynaadensis against multi drug resistant organisms (MDRO's) associated with diabetic patients. The drug resistant pathogens implicated in wound and urinary tract infection of diabetic patients were isolated and identified by molecular sequencing. Solvent-solvent fractionation of crude methanol extract produced hexane, chloroform, ethyl acetate and methanol-water fraction, among which chloroform fraction was found to be potent when compared with other three fractions. Further, chloroform fraction was subjected to preparatory HPLC (High-Performance Liquid Chromatography), that produced four sub-fractions; chloroform HPLC fraction 1 (CHF1) through CHF4. Among the sub-fractions, CHF1 inhibited the pathogens effectively in comparison to other three sub-fractions. The purity of CHF1 was found to be >95%. Therefore, CHF1 was further characterized by NMR and FTIR analysis and based on the structure elucidated, the compound was found to be 3,3',4'-Trihydroxyflavone. The effective dose of this bioactive compound ranged from 32 µg/mL to 1.2 mg/mL. Thus, the present study shows that 3,3',4'-Trihydroxyflavone isolated from J. wynaadensis is an interesting biopharmaceutical agent and could be considered as a source of antimicrobial agent for the treatment of various infections and used as a template molecule for future drug development.

Lipophilicity and antibacterial activity of flavonols: antibacterial activity of resinous exudates of Haplopappus litoralis, H. chrysantemifolius and H. scrobiculatus / Lipofilia y actividad antibacteriana de flavonoles: actividad antibacteriana de los exudados resinosos de Haplopappus litoralis, H. chrysantemifolius y H. scrobiculatus

The antibacterial properties of the resinous exudates from Haplopappus litoralis, H. chrysantemifolius and H. scrobiculatus from Central Chile were assessed against Gram negative and Gram-positive bacteria, and proved active against the latter. The results show that the antibacterial activities of the resinous exudates are independent from the flavonols isolated from each extract that proved to be inactive. The estimated lipophilicity of the flavonols isolated from the Haplopappus resinous exudates were compared with the lipophilicity of known antibacterial flavonols. This analysis showed that lipophilicity is an important variable to predict the antibacterial activity of flavonols.

La actividad antibacteriana de los exudados resinosos de Haplopappus litoralis, H. chrysantemifolius y H. scrobiculatus de la Zona Central de Chile fueron evaluadas frente a bacterias Gram-negativas y Gram-positivas, y resultaron activos frente a estas últimas. Los resultados mostraron que la actividad antibacteriana de los exudados resinosos es independiente de los flavonoles aisladas de cada extracto que no mostraron actividad antibacteriana. La lipofilia estimada de los flavonoles aislados de los exudados resinosos de Haplopappus se comparó con la lipofilia de conocidos flavonoles antibacterianos. Este análisis mostró que la lipofilia es una variable importante para predecir la actividad antibacteriana de los flavonoles.

Inhibition of peroxidase activity and scavenging of reactive oxygen species by astilbin isolated from Dimorphandra mollis (Fabaceae, Caesalpinioideae)

Astilbin (5,7,3’,4’-tetrahydroxy-2,3-dihydroflavonol-3-ß-o-rhamnoside), a flavonoid with a large range of biological activities, was isolated from Dimorphandra mollis, a shrub common to the Brazilian Cerrado. The purpose of this study is to verify the effects of astilbin on myeloperoxidase (MPO) and horseradish peroxidase (HRP), and its antioxidant activity against hypochlorous acid (HOCl) and total antioxidant activity (TAC) by the 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS•+). Astilbin inhibited MPO and HRP activities in a concentration-dependent relationship and effectively scavenged HOCl. The TAC by ABTS•+ of astilbin (IC50 ~ 20 mM) was higher than that of uric acid, which was used as a positive control. These data demonstrate that astilbin is a potent antioxidant and that it inhibits MPO and HRP activities efficiently.

Phytochemical and some pharmacological properties of certain plants belonging to Asteraceae family

The aerial parts of three plants belonging to Family Asteraceae: Inula crithmoides, Iphiona scarab and Jasonia montana were investigated. Phytochemicals isolated from Inula crithmoides were identified as: isopimpinellin [I], scoparone [II], psoralene [III], kaempferol-3-O-alpha-L-rhamnopyranoside [IV], kaempferol -3, 7- di-O-alpha-L-rhamnopyranoside [V], kaempferol-3-O-beta- D-glucopyranoside-7-O-alpha-L-rhamnopyranoside [VI] and isorhamnetin-3-O-beta-D-glucopyranoside-7-O-alpha-L-rhamnopyranoside [VII]. From Iphiona scarba umbelliferone [VIII], xanthotoxol [IX], marmesin [X], alpha-amyrin [XI], stigmasterol [XII] and beta-sitosterol [XIII] were isolated. Moreover, Jasonia montana was found to contain 7-hydroxy-3, 5, 6, 3',. 4'-pentamethoxy flavone [XIV], 5, 7-dihydroxy- 3, 6, 3', 4' -tetramethoxy flavone [XV] and 5, 7-dihydroxy-3, 3', 4' -trimethoxy flavone [XVI], in addition to ferulic acid, caffeic acid, chrorogenic acid, alpha-amyrin, stigmasterol and beta-sitosterol. Inula crithmoides aqueous methanolic extract showed significant inhibitory effect on mouse lymphoma [Cell line L1210] in vitro study in concentration dependant manner starting from 12.5 up to 250 microg/ml [20 - 100% inhibition], respectively. In vivo study, the results indicated that Inula crithmoides methanolic extract had significant antioxidant effect against mycotoxin [Ochratoxin A]-induced oxidative stress in rat. Iphiona scabra and Jasonia montana ethanolic extracts showed potent acute anti-inflammatory, anticoagulant and hypotenssive activities comparing to the standard drugs [indomethacine]

new flavonol glucoside from the growing buds of Allium cepa L. [red onion]

Phytochemical study of the butanol extract of the growing buds of the bulbs of red onion [Allium cepa L.] has been resulted in the isolation of four flavonoidal compounds, quercetin 1, quercetin-3'-omi-beta-D-glucopyranoside 2, quercetin-7, 3'-omi-beta-D-diglucopyranoside 3 and a new compound named as Alluceposide 4. Identity of these compounds was established on the basis of their physical and spectral data. The antioxidant activity was carried out for the total butanol extract and the isolated compounds and a significant result was obtained