title: Anti-complementary activity of Crataegus sinaica.
abstract: The 80% and 70% acetone extracts from fruits and leaves of Crataegus sinaica Boiss (Rosaceae) and the ethyl acetate-, butanol-, and water-fractions obtained from these initial extracts as well as the isolated compounds, quercetin (1) (1), hyperoside (quercetin 3-O-galactoside) (2) (2), rutin (quercetin 3-O-rutinoside) (3) (2), vitexin (4) (1), rhamnosylvitexin (5) (3), monoacetylrhamnosylvitexin (6) (3), epicatechin (7) (4), procyanidin B-5 (8) (4), proanthocyanidin A-2 (9) (5), procyanidin B-2 (10) (4), and procyanidin C-1 (11) (4), were tested for their influence on the classical (CP) and alternative (AP) pathways of complement-mediated hemolysis. All extracts and fractions showed a strong anti-complementary effect in a dose-dependent way which was more pronounced on the CP than on the AP. The results indicated that the pure proanthocyanidins were active on the CP. Procyanidin C-1 and proanthocyanidin A-2 were the most active on the CP and also showed activity on AP, whereas the flavonoids isolated were generally less active. However, rutin, showed a strong activity, quercetin and rhamnosylvitexin a moderate activity on the CP. This is the first report on the chemical constituents and complement-modulating activity of C. sinaica and on the occurrence of proanthocyanidin A-2 (9) in hawthorn.
authors.affiliation: Pharmaceutical Sciences Department, NRC, Cairo, Egypt.
authors.forename: A A
authors.initials: AA
authors.lastname: Shahat
authors.forename: F
authors.initials: F
authors.lastname: Hammouda
authors.forename: S I
authors.initials: SI
authors.lastname: Ismail
authors.forename: S A
authors.initials: SA
authors.lastname: Azzam
authors.forename: T
authors.initials: T
authors.lastname: De Bruyne
authors.forename: A
authors.initials: A
authors.lastname: Lasure
authors.forename: B
authors.initials: B
authors.lastname: Van Poel
authors.forename: L
authors.initials: L
authors.lastname: Pieters
authors.forename: A J
authors.initials: AJ
authors.lastname: Vlietinck
mesh_terms: D044946:Biflavonoids; D002392:Catechin; D003169:Complement Inactivator Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D005638:Fruit / Q000737:chemistry*; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry*; D044945:Proanthocyanidins; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013056:Spectrophotometry, Ultraviolet
chemical_list: D044946:Biflavonoids; D003169:Complement Inactivator Proteins; D010936:Plant Extracts; D044945:Proanthocyanidins; C479578:procyanidin B; C479583:procyanidin C; D002392:Catechin