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Alzheimer's dementia is a neurodegenerative disease that affects the elderly population and causes memory impairment and cognitive deficit. Manifestation of this disease is associated to acetylcholine decrease; thus, Cholinesterase inhibition is the main therapeutic strategy for the treatment of Alzheimer's disease. In the present study, a series of aporphinoid alkaloids were tested as potential acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitors in vitro. Alkaloids liriodenine (3) and cassythicine (10) were the best inhibitors of both cholinesterases with IC50 values lower than 10 Î?M. In addition, these alkaloids demonstrated better inhibition of BChE than reference drug galantamine. In addition, some alkaloids showed selective inhibition. Laurotetatine clorhydrate (13) selectively inhibit AChE over BChE. On the contrary, pachyconfine (7) interacted more efficiently with BChE active site. Molecular modelling studies were performed in order to illustrate key interactions between most active compounds and the enzymes and to explain their selectivity. These studies reveal that the benzodioxole moiety exhibits strong interactions due to hydrogen bonds that form with the Glu201 (AChE) and Tyr440 (BChE) residues, which is reflected in the IC50 values. [ABSTRACT FROM AUTHOR]

Native species are recommended for use in landscape restoration because they adapt well to the local pedo-climatic conditions. Despite the high biodiversity in the Mediterranean, the use of native plants is hampered by the limited knowledge of their seed germination. This is particularly true for a number of plants which are appropriate for creating species-rich herbaceous communities. In this study, seeds of 35 species were collected in different roadside and degraded sites in rural and urban areas. Two experiments were carried out to determine the influence of light and thermal conditions on seed germination. In the first experiment, seeds of 17 species were tested at different temperatures (5, 15, and 25°C). At 15°C, seed germination was tested under both dark and light conditions. In the second experiment, the germination of 30 species was tested under alternating temperatures (25/15°C) and dark/light conditions. The responses of the various species differed in relation to thermal levels and light conditions, e.g., Bartsia trixago did not germinate in the dark at constant temperatures (5, 15, and 25°C), while in the light (15°C) and at alternating temperatures (25/15°C) in light and dark conditions, germination was over 60%. In both experiments, Tragopogon porrifolius and Triticum ovatum showed the highest germination rate (=88%). With the sole exception of Medicago orbicularis, all members of the Fabaceae showed no or low germination. The definition of the germination requirements of some Mediterranean species, highlighted in these experiments, provides useful information for the creation of low input green areas and environmental restoration using these species. [ABSTRACT FROM AUTHOR]

Candida antarctica lipase B was immobilized for the first time (at the author's knowledge) onto linear low density polyethylene (LLDPE) films. Polymer films were previously bonded to a commercial aluminum sheet using a simple support preparation method. Biocatalyst performance was evaluated in penthyl oleate synthesis at room temperature. Two different catalyst geometries were tested and compared: one aluminum‐polyethylene 50 mm × 50 mm foil (50CAT) or near 5 mm × 5 mm aluminum‐polyethylene foils (5CAT). The obtained results demonstrate that the biocatalyst obtained with 50 mm × 50 mm aluminum‐polyethylene foil or 50CAT is reusable in up to 7 cycles, easy to separate from reaction products, and economical in comparison with commercial Novozym 435. Novel and economical CALB/LLDPE/Al biocatalyst is an attractive alternative for possible applications in a continuous monolithic reactor and future industrial scaling up. [ABSTRACT FROM AUTHOR]