«Frangula alnus». Una especie recuperada para la flora valenciana

Se comunica el estado de conservación de Frangula alnus en la Comunitat Valenciana, con especial atención al análisis del grado de cumplimiento de los objetivos marcados para su descatalogación como especie “En peligro de extinción” en el territorio valenciano según el Catálogo Valenciano de Especies de Flora Amenazadas. En la actualidad el número de plantas en la Comunidad Valenciana es de 897, de las cuales 869 plantas han sido translocadas, distribuidas en 24 poblaciones, de las cuáles 22 han sido creadas mediante translocaciones.

Potential of Frangula alnus to contribute to food safety: antibiofilm effect against Staphylococcus aureus

Contamination by numerous food-borne pathogens is a major challenge facing the food industry daily. Even though there are many strategies in the fight against contamination, pathogens able to attach to different surfaces and form biofilms are the biggest concern. Staphylococcus aureus is a common food-borne pathogen capable of forming biofilms on foods and food contact surfaces. The prevalence of multidrug resistant S. aureus is high in raw products, high-protein foods and processed products. Bearing in mind S. aureus resistance to numerous antibacterial agents, the aim of this study was to investigate antibiofilm activity of an ethyl-acetate extract of the medicinal plant, Frangula alnus, against S. aureus ATCC 25923 and S. aureus ATCC 43300. It was demonstrated that extract reduced survival of both tested strains by up to 67%. Furthermore, quantification of biofilm biomass showed that extract possesses the extraordinary ability to inhibit biofilm formation of both tested strains (up to 91%). On the other hand, the effect on preformed biofilm was less pronounced and measured only for S. aureus ATCC 43300, wherein about 28% of preformed biofilm was eradicated. The results obtained in this study encourage further investigation of F. alnus as a novel antibiofilm agent or preservative in the food industry.

Counter-Intuitive Response to Water Limitation in a Southern European Provenance of Frangula alnus Mill. in a Common Garden Experiment

Climate change will intensify drought periods during the growing season in Western Europe. We mimicked this prediction by withholding water in summer from young rooted cuttings of Frangula alnus Mill., a common shrub species, originating from different latitudes in Europe (Italy, Belgium and Sweden) and growing in a common garden environment in Belgium. We followed the responses to the drought up to two years after the treatment. Counter-intuitively, the Italian provenance displayed earlier symptoms and stronger effects of water limitation than the other two provenances. A putative higher transpiration in this provenance could be suggested based on a relative larger shoot growth, larger leaves and a higher stomatal density. After the post-drought re-watering, the droughted plants of the Italian provenance entered leaf senescence later than the control plants, likely as a compensation mechanism for the lost growing time. Bud burst in the first year after the drought treatment and leaf senescence in the next autumn were both advanced in the drought treated group when compared with the control plants. Bud burst in the second year after the drought treatment did not display any differentiation anymore between control and drought treated plants. Growth traits also displayed legacies of the water limitation. For example, the drought treated plants showed a lower number of reshoots upon pruning in the year after the drought treatment. Our results suggest that assisted migration from southern Europe to western Europe as a climate change adaptation strategy might not always follow the expected patterns.

Polyphenols of Frangula alnus and Peganum harmala Leaves and Associated Biological Activities

Frangula alnus and Peganum harmala populations growing in Saudi Arabia might be rich sources of natural compounds with important biological activities. A high performance liquid chromatography diode array revealed several polyphenols in the leaf extracts for the first time, including p-coumaric acid, rosmarinic acid, chlorogenic acid, ferulic acid, quercitrin, rutoside, quercetin and trifolin in F. alnus; and hydrocaffeic acid, protocatechuic acid, rosmarinic acid, caffeic acid and cynaroside in P. harmala. F. alnus and P. harmala showed strong antioxidant effects attributed to the polyphenolic composition of leaves and reduction of reactive oxygen species (ROS) accumulation. F. alnus and P. harmala leaf extracts showed cytotoxic effects against Jurkat, MCF-7, HeLa, and HT-29 cancer cells using MTT and flow cytometry assays. These activities were attributed to the polyphenolic composition of leaves including quercitrin, trifolin and cymaroside, as well as the activation of caspase family enzymes 2, 6, 8 and 9 in treated cancer cells compared to control. The current findings of this study include a novel comprehensive investigation on the polyphenol composition and anticancer effects of leaf extracts of F. alnus and P. harmala from natural populations in Saudi Arabia.