Chemical Constituents of Cyperus esculentus Leaves and the Protective Effect against Agricultural Fungicide-Induced Hepatotoxicity.

Cyperus esculentus is cultivated as a crop plant due to its edible and oily tubers (tiger nut). However, little is known about the phytochemicals and bioeffects of the leaves. This study was conducted to identify and quantify the chemical constituents of C. esculentus leaves and evaluate their bioactivities. By liquid chromatography-mass spectrometry, 30 compounds including flavan-3-ols, caffeic acid derivatives, and flavones, were identified from the leaves. The quantitative analysis revealed that gallocatechin (8), procyanidin B1 (15), catechin (16), chlorogenic acid (19), orientin (30), and luteolin 7-O-glucuronide (31) are the major chemical constituents of C. esculentus leaves. The contents of these six chemical constituents in the leaves collected in September in Hohhot, China, reached to 1460.85±7.66, 10178.77±302.65, 1048.35±17.37, 1722.15±26.13, 5318.62±277.16, and 1526.54±11.95 µg, respectively, in one gram of the dried leaves. The leaf extract (CELE) showed strong antioxidant activity in vitro, with compounds 8, 15, and 19 contributing the most. CELE showed significant protection against the agricultural fungicide tebuconazole-induced developmental toxicity and hepatotoxicity in zebrafish.

Flavan-3-ol-cysteine and acetylcysteine conjugates from edible reagents and the stems of Cynomorium songaricum as potent antioxidants.

Flavan-3-ol derivatives, including 3 cysteine conjugates and 3 acetylcysteine conjugates, were prepared using Cynomorium songaricum and edible reagents. The structures were determined, based on NMR and MS spectra. All compounds had stronger radical-scavenging activity than catechin and epicatechin. Moreover, the cysteine conjugates were active against α-glucosidase, whereas catechin and epicatechin were not. Two acetylcysteine flavan-3-ol conjugates, 4ß-(L-acetylcysteinyl)-epicatechin 3-O-gallate and 4ß-(L-acetylcysteinyl)-epiafzelechin, are novel compounds with better logP values than their cysteine counterparts. These conjugates can be prepared from purified flavan-3-ol polymers or directly from herbal material.

Chemical constituents and pharmacologic actions of Cynomorium plants.

The stem of Cynomorium songaricum is a traditional Chinese medicine reputed to have tonic effects. C. coccineum growing in northern Africa and the Mediterranean region is regarded in Arabian medical practice as the "treasure of drugs". The major constituents of Cynomorium plants have been revealed to be phenolic compounds, steroids, triterpenes, etc. Pharmacologic studies showed that the Cynomorium plants had antioxidant, immunity-improving, anti-diabetic, neuroprotective, and other bioactivities. Some chemical constituents in Cynomorium plants are unstable, implying that the chemical components of the herbal medicines produced under different conditions may be variable. This review covers the literature published until December, 2011 and describes the pharmacologic effects and secondary metabolites of Cynomorium species.