title: Determination of new immunoadjuvant saponin named QB-90, and analysis of its organ-specific distribution in Quillaja brasiliensis by HPLC.
abstract: An LC method was developed and validated in order to quantify the saponin purified fraction named QB-90 obtained from the aqueous extracts of Quillaja brasiliensis leaves. Previously, QB-90 was shown to be active as adjuvant in an experimental vaccine for herpesvirus bovine type 1 in mice. The analysis was performed using an RP-8 column with acetonitrile:water isocratic elution at 214 nm. The standard curve for QB-90 was linear over the range of 0.8-10 µg mL(-1) (r = 0.9996). The aqueous extract showed linear response in the range of 50-1000 µg mL(-1) (r = 0.9996). The proposed method showed adequate repeatability and intermediary precision. The limits of detection (LOD) and quantification (LOQ) were 0.074 and 0.248 µg mL(-1), respectively. This method was applied successfully to analyse QB-90 organ-specific distribution in field stands of Q. brasiliensis and in laboratory-grown seedlings. Leaves from young plants accumulated higher QB-90 amounts than leaves from adult trees.
authors.affiliation: Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Ipiranga, 2752, 90610-000 Porto Alegre, RS, Brazil.
authors.forename: Juliane D
authors.initials: JD
authors.lastname: Fleck
authors.forename: Fernanda
authors.initials: F
authors.lastname: de Costa
authors.forename: Anna C A
authors.initials: AC
authors.lastname: Yendo
authors.forename: Jéferson
authors.initials: J
authors.lastname: Segalin
authors.forename: Teresa C T
authors.initials: TC
authors.lastname: Dalla Costa
authors.forename: Arthur G
authors.initials: AG
authors.lastname: Fett-Neto
authors.forename: Grace
authors.initials: G
authors.lastname: Gosmann
mesh_terms: D000276:Adjuvants, Immunologic / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D018515:Plant Leaves / Q000737:chemistry; D031990:Quillaja / Q000737:chemistry*; D012503:Saponins / Q000737:chemistry*
chemical_list: D000276:Adjuvants, Immunologic; D012503:Saponins