Yihai Wang

Antidiabetic and antioxidant effects and phytochemicals of mulberry fruit (Morus alba L.) polyphenol enhanced extract.

The antidiabetic and antioxidant activities of the ethyl acetate-soluble extract (MFE) of mulberry fruit (Morus alba L.) were investigated. In vitro, MFE showed potent α-glucosidase inhibitory activity and radical-scavenging activities against DPPH and superoxide anion radicals. In vivo, MFE could significantly decrease fasting blood glucose (FBG) and glycosylated serum protein (GSP), and increase antioxidant enzymatic activities (SOD, CAT, GSH-Px) in streptozotocin (STZ)-induced diabetic mice. Bioactivity-guided fractionation of the MFE led to the isolation of 25 phenolic compounds, and their structures were identified on the basis of MS and NMR data. All the 25 compounds were isolated from mulberry fruit for the first time. Also, the α-glucosidase inhibitory activity and antioxidant activity of the phenolics were evaluated. Potent α-glucosidase inhibitory and radical-scavenging activities of these phenolics suggested that they may be partially responsible for the antidiabetic and antioxidant activities of mulberry fruit.

Health benefits of wine: Don’t expect resveratrol too much

Moderate consumption of red wine reduces the risk of heart disease and extends lifespan, which these healthy benefits are often attributed to its high antioxidant content. The relative contributions of wine polyphenols in healthy benefits were studied in this study. Among all wine polyphenols, caffeic acid was the richest one, while gallic acid showed the highest free radical scavenging activity. There was no significant difference between the prime red wine and the red wine adding 10-fold resveratrol on neuroprotective effects on SH-SY5Y cell line. The contribution percentage of resveratrol to the antioxidant activity of red wine was less than other tested polyphenols. It suggested that resveratrol may be negligible with respect to healthy benefits of red wine.

Cytotoxic ceramides and glycerides from the roots of Livistona chinensis

A 70% ethanol extract of the roots of Livistona chinensis has been investigated, led to the isolation of 13 compounds, including a new ceramide, (2S,3S,4R,9Z)-2-[(2R)-2-hydroxytricosanoylamino]-9-octadecene-1,3,4-triol (2), a new glycosyl ceramide, 1-O-β-D-glucopyranosyl-(2S,3S,4R,9Z)-2-[(2R)-2-hydroxydocosanoylamino]-9-octadecene-1,3,4-triol (3), three new monoacylglycerols, 1-(34-hydroxytetratriacontanoyl)-sn-glycerol (9), 1-[nonadeca-(9Z,12Z)-dienoyl]-sn-glycerol (10), and 1-[12-hydroxypentatriaconta-(13E,15Z)-dienoyl]-sn-glycerol (11), a new diacylglycerol, 1-(heptadeca-6Z,9Z-dienoyl)-3-(octadeca-6Z,9Z,12Z-trienoyl)-sn-glycerol (12), as well as a new diacylglycerol aminoglycoside, 1-octadecanoyl-2-nonadecanoyl-3-O-(6-amino-6-deoxy)-β-D-glucopyranosyl-sn-glycerol (13). The structures of new compounds were elucidated, based on spectroscopic, zymologic and chemical methods. Among the compounds tested, compounds 3, 4 and 13 showed significantly antiproliferative effects against the human tumor cell lines (K562, HL-60, HepG2, and CNE-1) with the IC₅₀ of 10-65 μM. To our knowledge, this is first report of the occurrence of ceramides and acylglycerols in the genus Livistona.

Neuroprotection of brain-targeted bioactive dietary artoindonesianin O (AIO) from mulberry on rat neurons as a novel intervention for Alzheimer's disease.

The novel effects of artoindonesianin O, a dietary phenolic compound from mulberry, were investigated on oligomer Aβ42-, NMDA- or okadaic-acid-induced neurotoxicity and the restorative effect on the oligomer Aβ42-induced synapses dysfunction using rat hippocampus neuron cells in vitro. The phenolic compound of AIO can exert neuroprotection by blocking oligomer Aβ42- or NMDA-induced neurotoxicity and okadaic-acid-induced tau protein hyperphosphorylation through inhibiting the expression of kinase p-ERK1/2. Meanwhile, it is also beneficial to synaptic plasticity. These interesting results strongly suggest that AIO, which is rich in abundant sources of mulberry and other fruits, is suitable and possible candidate for the development of general food type neuroprotection on AD by protecting against brain damage and memory impairment.