Mammalian Arginase Inhibitory Activity of Methanolic Extracts and Isolated Compounds from Species.

Polyphenolic enriched extracts from two species of , and , possess mammalian arginase inhibitory capacities, with the percentage inhibition ranging from 80% to 95% at 100 µg/mL and 40% to 64% at 10 µg/mL. Phytochemical investigation of these species led to the isolation and identification of two new natural stilbene oligomers named thunbergin A-B (-), together with three other stilbenes, -resveratrol (), -scirpusin A (), -cyperusphenol A (), and two flavonoids, aureusidin () and luteolin (), which were isolated for the first time from and . Structures were established on the basis of the spectroscopic data from MS and NMR experiments.

Arginase inhibitory properties of flavonoid compounds from the leaves of Mulberry (Morus alba, Moraceae).

Objectives: We aimed to isolate and identify bioactive molecules from Morus alba (Moraceae) leaves having arginase inhibitory activity towards the combat of clinical outcomes related to endothelial dysfunction.

Method: Extraction and isolation were carried out by successive macerations, prepurification by using a Solid Phase Extraction (SPE) and separation using preparative PLC. The structures of the isolated components were established and confirmed by spectroscopic analyses, including the ESI-HRMS and NMR spectroscopic investigations.

Cyperaceae Species Are Potential Sources of Natural Mammalian Arginase Inhibitors with Positive Effects on Vascular Function.

The inhibition of arginase is of substantial interest for the treatment of various diseases of public health interest including cardiovascular diseases. Using an ex vivo experiment on rat aortic rings and an in vitro assay with liver bovine purified arginase, it was demonstrated that several polyphenolic extracts from Cyperus and Carex species possess vasorelaxant properties and mammalian arginase inhibitory capacities. Phytochemical studies performed on these species led to the identification of eight compounds, including monomers, dimers, trimers, and tetramers of resveratrol.

Bioactive stilbenes from Vitis vinifera grapevine shoots extracts.

Background: Viticultural residues from commercial viticultural activities represent a potentially important source of bioactive stilbenes such as resveratrol. The main aim of the present study was therefore to isolate, identify and perform biological assays against amyloid-β peptide aggregation of original stilbenes from Vitis vinifera shoots.

Results: A new resveratrol oligomer, (Z)-cis-miyabenol C (3), was isolated from Vitis vinifera grapevine shoots together with two newly reported oligostilbenes from Vitis vinifera shoots, vitisinol C (1) and (E)-cis-miyabenol C (2), and six known compounds: piceatannol, resveratrol, (E)-ε-viniferin (trans-ε-viniferin), ω-viniferin, vitisinol C and (E)-miyabenol C.