Antiinflammatory and antibacterial activities of C-methylflavonols fromPiliostigma thonningii

Abstract

Newly described C‐methylflavonols, 6,8‐di‐C‐methylquercetin 3‐methyl ether, 6‐C‐methylquercetin 3,7‐dimethyl ether, 6,8‐di‐C‐methylquercetin 3,7‐dimethyl ether together with the known compounds quercetin, quercitrin, 6‐C‐methylquercetin 3‐methyl ether, 6‐C‐methylquercetin 3,7,3′‐trimethyl ether, 6,8‐di‐C‐methyl‐ kaempferol 3‐methyl ether and 6,8‐di‐C‐methylkaempferol 3,7‐dimethyl ether isolated from the leaves of Piliostigma thonningii, were tested for their ability to inhibit prostaglandin synthesis in vitro and antibacterial activity against Staph. aureus. The influence of the B ring 3′,4′ diol group on the activity of C‐methylflavonols in the inhibition of prostaglandin synthesis differ from that observed for a series of flavonoids without C‐methyl groups. The antibacterial activity in the series mirror those of methylated antimicrobial flavonoids. The traditional uses of the plant in infections and inflammatory conditions were rationalized on the basis of the activities of these compounds. © 1997 John Wiley & Sons, Ltd.

Medicinal plants used in the management of chronic joint pains in Machakos and Makueni counties, Kenya

“…In vivo anti-inflammatory and antibacterial activity; C-methylflavonols (Ibewuike et al, 1997;Olakunle, 2011). Antibacterial activity; antihelmintic activity (Akinpelu and Obuotor, 2000) Leaves chewed to cure stomach pains in East Africa (Kokwaro, 1993).…”

Flavonols and an oxychromonol from Piliostigma reticulatum

“…Ethnomedically, the bark, root, pod, young stem or leaves have been used for treating leprosy, smallpox, coughs, ulcer, heart pain, gingivitis, snake bite, dysentery, fever, wounds and a variety of closely related disease conditions (Irvine, 1961;Asuzu and Onu, 1994;Bombardelli et al, 1973Bombardelli et al, , 1992Bombardelli et al, , 1994Dalziel, 1937;Watt and Breyer-Brandwijk, 1962;McGaw et al, 1997;Okwute et al, 1986). Previously isolated constituents include flavonoids and proanthocyanidins (Snatzke and Wolff, 1989;Lamikanra et al, 1990;Komiya et al, 1975), labdane derivatives (Hashidoko et al, 1991;Huang et al, 1993), a kaurane diterpene (Roitman and James, 1985;Martin et al, 1997), C-methylflavonols (Breitmeier and Voelter, 1990;Harborne et al, 1994;Rabesa and Voirin, 1985;Voirin, 1983;Aderogba et al, 2003;Rasamoelisendra et al, 1989) and phenoxychromones (Ibewuike et al, 1996(Ibewuike et al, , 1997, while broad phytochemical analysis showed the presence of other classes of constituents such as saponins, tannins and polyphenols (Irvine, 1961;Bombardelli et al, 1994).…”

“…Among quercetins some have been shown to exhibit strong lipid peroxidation inhibitory effects and cytotoxicity (Cos et al, 2001) when tested against oral microorganisms. Thus, the present findings on the antimicrobial activities of the C-methylated flavonols and the oxychromonol isolated from P. reticulatum (Ibewuike et al, 1997) lend support to the well founded effectiveness of flavonoids and closely related structures against microbial infections, and hence provide justification for the usage of this plant in folk medicine for the treatment of viral infections, oral sores and inflammations (Iinuma et al, 1994;Kirtikar et al, 1993;Yusuf et al, 1994;Liu et al, 1990).…”

In vitro Bioactivity and Antimicrobial Activity of Picea abies and Larix decidua Wood and Bark Extracts

“…Most antibacterial activity data concerns aglycones, and only small amounts of data on glycosides can be found (Metsämuuronen and Siren 2014). Out of all these flavonoids, aglycones, quercetin (RiceEvans et al 1996;Ibewuike et al 1997;Puupponen-Pimiä et al 2001), kaempferol (Rauha et al 2000), and myricetin (Puupponen-Pimiä et al 2001) have already been recognized to possess antibacterial activity. However, quercetin-3-glucoside (quercitrin) (PuupponenPimiä et al 2001) has actually been found to be inactive.…”