RESUMEN
The Pycnoporus fungi are white-rot basidiomycetes listed as food- and cosmetic-grade microorganisms. Three high redox potential laccases from Pycnoporus coccineus and Pycnoporus sanguineus were tested and compared, with the commercial Suberase® as reference, for their ability to synthesise natural active oligomers from rutin (quercetin-3-rutinoside, one of the best-known naturally occurring flavonoid glycosides). The aim of this work was to develop a process with technical parameters (solvent, temperature, reaction time and raw materials) that were easy to scale up for industrial production and compatible with cosmetic and pharmaceutical formulation guidelines. The aqueous mixture of glycerol/ethanol/buffer described in this study met this requirement and allowed the solubilisation of rutin and its oxidative bioconversion into oligomers. The four flavonoid oligomer mixtures synthesised using laccases as catalysts were analysed by high performance liquid chromatography-diode array detection-negative electrospray ionisation-multistage mass spectrometry. Their chromatographic elution profiles were compared and 16 compounds were characterised and identified as dimers and trimers of rutin. The oligorutins were different in Suberase® and Pycnoporus laccase reaction mixtures. They were evaluated for their antioxidant, anti-inflammatory and anti-ageing activities on specific enzymatic targets such as cyclooxygenase (COX-2) and human matrix metalloproteinase 3 (MMP-3). Expressed in terms of IC(50), the flavonoid oligomers displayed a 2.5- to 3-fold higher superoxide scavenging activity than monomeric rutin. Pycnoporus laccase and Suberase® oligorutins led to an inhibition of COX-2 of about 35% and 70%, respectively, while monomeric rutin showed a near-negligible inhibition effect, less than about 10%. The best results on MMP-3 activity were obtained with rutin oligomers from P. sanguineus IMB W006-2 laccase and Suberase® with about 70-75% inhibition.
Asunto(s)
Proteínas Fúngicas/metabolismo , Lacasa/metabolismo , Pycnoporus/metabolismo , Rutina/metabolismo , Antioxidantes/química , Antioxidantes/metabolismo , Antioxidantes/farmacología , Biotecnología , Biotransformación , Ciclooxigenasa 2/metabolismo , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/farmacología , Humanos , Metaloproteinasa 3 de la Matriz/metabolismo , Inhibidores de la Metaloproteinasa de la Matriz , Estructura Molecular , Pycnoporus/química , Pycnoporus/enzimología , Rutina/química , Rutina/farmacologíaRESUMEN
Xanthones, and more specifically mangiferin, are molecules used in cosmetics for their photoprotective and anti-aging properties. The richness in xanthones of Aphloia theiformis leaves, a common shrub in Madagascar, can reach almost 12% (in relation to dry biomass). Amongst the A. theiformis studied, two major groups of individuals have been determined: those presenting a high proportion of mangiferin (up to 80% of the xanthones) and those presenting a high proportion of polar xanthones (not yet identified). Our study shows that: i) for each subject, the xanthone content remains stable over time (no seasonal variation); ii) the majority of the trees developing in the light belong to the first group (rich in mangiferin), whereas the individuals growing in the undergrowth are richer in polar xanthones; iii) the distribution of the two groups seems not to have any correlation with taxonomy and, moreover, with the known varieties of A. theiformis, although the micrantha variety is richer in mangiferin. Overall, this information indicates that A. theiformis is a reservoir of xanthones and makes it possible to define a framework for its reasoned management.