1. Research and Development Department of Nutrafur-Furfural Español S.A., Camino Viejo de Pliego s/n, 80320 Alcantarilla, Murcia, Spain, Plant Biology Department, Faculty of Biology, University of Murcia, 30100 Espinardo, Murcia, Spain, and Research and Development Department of Flavex Naturextrakte GmbH, Nordstrasse 7, D-66780 Rehlingen-Siersburg, Germany