title: Anti-inflammatory activity and QSAR studies of compounds isolated from Hyacinthaceae species and Tachiadenus longiflorus Griseb. (Gentianaceae).
abstract: Twenty-two homoisoflavanones and structurally related compounds isolated from plants were screened for anti-inflammatory activity. Seventeen compounds were isolated from southern African Hyacinthaceae species, one from the Madagascan gentian Tachiadenus longiflorus Griseb. and four were of synthetic origin. Inhibition of prostaglandin synthesis in cell microsomal fractions was first evaluated, followed by screening for specific inhibition of isolated cyclooxygenase enzymes (COX-1 and COX-2). Six homoisoflavanone and structurally related compounds showed significantly high levels of anti-inflammatory activity in the microsomal fraction assay. Only one compound exhibited a high level of anti-inflammatory activity in the COX-1 enzyme assay and no significant activity was detected in the COX-2 enzyme assay. Biological screening was followed by a computer-based quantitative structure-activity relationship (QSAR) study. The physicochemical descriptors: strain energy, heat of formation, volume, surface area, aqueous phase energy, dipole moment, enthalpy, entropy, molar refractivity, parachor, density, refractive index, surface tension, polarizability, logP, Van der Waals interaction energy, Coulombic interaction energy and nonbonded interaction energy were used to characterize the structures of the homoisoflavanones and structurally related compounds. This study produced three equations with significant prediction values for the anti-inflammatory activity of the compounds investigated. The derived models also provided valuable parameter guidelines for those properties influencing the anti-inflammatory activity of the studied compounds.
authors.affiliation: Natural Products Research Group, School of Chemistry, University of KwaZulu-Natal, Durban 4041, South Africa.
authors.forename: Karen
authors.initials: K
authors.lastname: du Toit
authors.forename: Esameldin E
authors.initials: EE
authors.lastname: Elgorashi
authors.forename: Sarel F
authors.initials: SF
authors.lastname: Malan
authors.forename: Siegfried E
authors.initials: SE
authors.lastname: Drewes
authors.forename: Johannes
authors.initials: J
authors.lastname: van Staden
authors.forename: Neil R
authors.initials: NR
authors.lastname: Crouch
authors.forename: Dulcie A
authors.initials: DA
authors.lastname: Mulholland
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000302:isolation & purification* / Q000494:pharmacology; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D004791:Enzyme Inhibitors / Q000302:isolation & purification* / Q000494:pharmacology; D029965:Gentianaceae / Q000737:chemistry*; D006801:Humans; D019668:Liliaceae / Q000737:chemistry*; D008565:Membrane Proteins; D015394:Molecular Structure; D011451:Prostaglandin-Endoperoxide Synthases / Q000187:drug effects; D021281:Quantitative Structure-Activity Relationship
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D004791:Enzyme Inhibitors; D008565:Membrane Proteins; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; C496511:PTGS1 protein, human; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases