title: Thermal and photo stability of phenolic constituents of an Achyrocline satureioides spray-dried powder.
abstract: Thermal and the photo stabilities of an Achyrocline satureioides powder (SDP40) were evaluated in particular concerning the total polyphenol content as well as the main identified constituents quercetin, luteolin, 3-O-methylquercetin and caffeic acid. SDP40 presented good stability for nine months under normal storage conditions of 25 degrees C temperature and 60% relative humidity (RH). In accelerated term testing, 50 degrees C temperature and 90% RH and also in stress testing, 80 degrees C, caffeic acid and a non-identified constituent P3 were the most instable constituents. Luteolin and 3-O-methylquercetin were the most stable constituents. Quercetin presented an unusual behavior, improving its concentration after 1 month at 50 degrees C or 2 days at 80 degrees C exposition, followed by a decrease in its concentration. The hypothesis that this observation is related to the simultaneous decreasing of a non-identified peak P3 or to the hydrolysis of a non-identified precursor as a quercetin heteroside is being investigated. The SDP40 presented good stability against UV-C light when conditioned in amber or transparent containers, but it suffered degradation when stored in open-dishes. In summary, the total polyphenol content remains within acceptable limits of 10% under normal storage conditions for nine months. However, the LC polyphenol analysis demonstrated that the behavior of individual constituents has still to be enlightened.
authors.affiliation: Programa de Pós-graduagdo em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: M H
authors.initials: MH
authors.lastname: Holzschuh
authors.forename: D M
authors.initials: DM
authors.lastname: Silva
authors.forename: E E S
authors.initials: EE
authors.lastname: Schapoval
authors.forename: V L
authors.initials: VL
authors.lastname: Bassani
mesh_terms: D036921:Achyrocline / Q000737:chemistry*; D002853:Chromatography, Liquid; D003116:Color; D003890:Desiccation; D004355:Drug Stability; D005419:Flavonoids / Q000737:chemistry* / Q000528:radiation effects; D006358:Hot Temperature; D008027:Light; D010636:Phenols / Q000737:chemistry* / Q000528:radiation effects; D010777:Photochemistry; D059808:Polyphenols; D011208:Powders; D012015:Reference Standards; D012903:Smell; D013696:Temperature; D013997:Time Factors; D014466:Ultraviolet Rays
chemical_list: D005419:Flavonoids; D010636:Phenols; D059808:Polyphenols; D011208:Powders