A new alkaloid from Helianthemum ordosicum

Chemical Constituents From Endiandra kingiana (Lauraceae) as Potential Inhibitors for Dengue Type 2 NS2B/NS3 Serine Protease and its Molecular Docking

A phytochemical study on the bark of Endiandra kingiana Gamble (Lauraceae) led to the isolation of a new benzofuranone, 4-hydroxy-6-(9,13,17-trimethyldodeca-8,12,16-trienyl)-2(3 H)-benzofuranone (1), together with 6 known compounds. Their structures were established on the basis of detailed spectroscopic analysis, including one- and two-dimensional nuclear magnetic resonance (NMR) and electrospray Ionisation mass spectrometry techniques. Compounds 1-3 showed moderate inhibition against dengue virus type 2 NS2B/NS3 protease with percentage inhibitions of 61.23 ± 6.96, 69.92 ± 3.34, and 62.02 ± 6.19, respectively. Molecular docking was performed to predict the binding mode of all protease inhibitor models and the results revealed that most of the essential amino acid residues such as Asp129, Ser135, Tyr161, Asn152, and His51 significantly interact with the ligands.

Synthesis and characterization of a (+)-catechin and L-(+)-ascorbic acid cocrystal as a new functional ingredient for tea drinks

Tea (Camellia Sinensis) is one of the most popular drink, consumed as infusion or bottled ready to drink beverages. Although tea leaves contain many antioxidants compounds, after processing they can drastically decrease, sometimes up to a full degradation, as in the case of catechin, a very healthy flavan-3-ol. In this context, the synthesis of a cocrystal between (+)-catechin and L-(+)-ascorbic acid, was proved to be a useful strategy to make a new ingredient able to ameliorate the antioxidant profile of both infusions and bottled teas. The obtained cocrystal showed a three-fold higher solubility than (+)catechin and its formation was elucidated unambiguously by FT-IR, thermal (DSC) and diffraction (PXRD) analyses. Antioxidant characteristics of the samples were evaluated by colorimetric assays. As expected, infusions showed much better antioxidant features than ready-to-use lemon and peach teas. The same trend was confirmed after the addition of the cocrystal at two concentration levels. In particular, supplementation at concentration of 2 mg mL-1 improved the bottled tea antioxidant values to the level showed by the not-added infusion tea.