Study Physicochemical Characteristics of Spring Honeys from Yunnan with the Application of HPLC-RI and FAAS.

Many special honeys are produced in Yunnan province due to abundant nectar plants and minerals resources provided by the unique natural environment in this area. In this work, the physicochemical property of three honeys (Viciacracca honey, Hevea brasiliensis honey and Punica granatum honey) from Yunnan was studied. The results showed that in different honeys the moisture content, electrical conductivity and dynamic viscosity were different. The sugar contents of each honey were determined with HPLC-RI. The results showed that P. granatum honey had the most abundant glucose [35.62 g·(100 g)-1], and H. brasiliensis honey had the most abundant fructose [41.03 g·(100 g)-1]. Thirteen different mineral elements in three honey species were determined with FAAS. It was found that the mineral level was from 167.24 mg·kg-1 in P. granatum honey to 437.34 mg·kg-1 in H. brasiliensis. Based on the mineral content the three honey species were classified following the principal component analysis (PCA) method. The result showed that Cu, Zn and Na could act as the elemental markers for V. cracca honey, while Mg, K, Ca, As and Cd act as the elemental markers for H. brasiliensis honey, and Fe, Mn, Ni, and Cr act as the elemental markers for P. granatum honey. This study reported the physicochemical property of three special Yunnan honeys, which could help the further study and utilization of these honeys.

Structural characterization and immunosuppressive activity of a new pregnane glycoside from Epigynum cochinchinensis.

Phytochemical investigation on the ethyl acetate fraction of the leaves of Epigynum cochinchinensis led to the isolation of a new C21 pregnane glycoside, epigycoside B (1), together with three known analogues. Their structures were elucidated on the basis of extensive spectroscopic techniques, including UV, MS, and NMR experiments, as well as the chemical methods. Compound 1 displayed in vitro immunosuppressive activity against concanavalin A (Con A)/Lipopolysaccharides (LPS)-stimulated proliferation of mice splenocyte. The activity was significant as compared with control group at 50 µM concentration.

Novel immunosuppressive pregnane glycosides from the leaves of Epigynum auritum.

Phytochemical investigation on the leaves of Epigynum auritum led to the isolation of three novel C21 pregnane glycosides, epigynosides, E-G (1-3), together with two known pregnane glycosides, epigynosides A (4) and C (5). Their structures were elucidated based on extensive spectroscopic data (MS, IR, 1D and 2D NMR) analysis, as well as comparison with the reported data. The immunological activities of the new compounds was evaluated against concanavalin A (Con A)-stimulated proliferation of mice splenocyte in vitro. Compounds 1-3 displayed significant immunosuppressive activities, close to the efficacy of the positive control (dexamethasone) at the concentration of 50µM.

Seco-pregnane glycosides from the stems of Epigynum auritum.

Chemical investigation of the stems of Epigynum auritum led to the isolation and identification of a novel 16,17-seco pregnane glycoside, epigynoside D, along with other three known compounds (2-4). The structure of compound 1 was elucidated by means of spectroscopic analysis, including HRESIMS, 1D and 2D NMR experiments. All isolated compounds were tested for their in vitro cytotoxic, immunological and anti-acetylcholinesterase activities.

A new immunosuppressive pregnane glycoside from aqueous fraction of Epigynum cochinchinensis.

Chemical investigation on the aqueous fraction of the stems of Epigynum cochinchinensis led to the isolation of a new pregnane glycoside named as epigycoside A (1) along with three known analogues (2-4). The structure of compound 1 was elucidated by means of spectroscopic techniques, including HRESIMS, and 1D and 2D NMR experiments. The immunosuppressive activity of 1 was evaluated by an in vitro model of concanavalin A-induced mice splenocytes proliferation. Compound 1 showed significant inhibitory activity in a dose-dependent manner, closer to the efficacy of positive control, dexamethasone, at a concentration of 50 µM.