Iristectorin A

Ultrafiltration-LC-MS combined with semi-preparative HPLC for the simultaneous screening and isolation of lactate dehydrogenase inhibitors from Belamcanda chinensis.[Pubmed:27734585]

J Sep Sci. 2016 Dec;39(23):4533-4543.

Stroke represents the fourth leading cause of death in the USA and the second leading cause of death worldwide. Lactate dehydrogenase inhibitors are widely used in the treatment of ischemic stroke and natural products are considered a promising source of novel lactate dehydrogenase inhibitors. In this study, we used PC12 cells to determine the protective effect of extracts from the herb Belamcanda chinensis following toxic challenge. Using ultrafiltration high-performance liquid chromatography coupled with photo-diode array detection and electrospray ionization mass spectrometry, we screened and identified isoflavonoids from Belamcanda chinensis extracts. Semi-preparative high-performance liquid chromatography was then applied to separate and isolate the active constituents. Using these methods, we identified six major compounds in Belamcanda chinensis as lactate dehydrogenase inhibitors: tectoridin, Iristectorin A, iridin, tectorigenin, irigenin, and irisflorentin, which were then isolated to >92% purity. This is the first report that Belamcanda chinensis extracts contain potent lactate dehydrogenase inhibitors. Our results demonstrate that the systematic isolation of bioactive components from Belamcanda chinensis guided by ultrafiltration high-performance liquid chromatography coupled with photo-diode array detection and electrospray ionization mass spectrometry represents a feasible and efficient technique that could be extended for the identification and isolation of other enzyme inhibitors.

Ionic liquid based ultrasonic assisted extraction of isoflavones from Iris tectorum Maxim and subsequently separation and purification by high-speed counter-current chromatography.[Pubmed:21444254]

J Chromatogr B Analyt Technol Biomed Life Sci. 2011 Apr 15;879(13-14):975-80.

We developed an ionic liquid based ultrasonic assisted extraction (ILUAE) method for the extraction of the three isoflavones, namely tectoridin, iristectorin B and Iristectorin A from Iris tectorum Maxim of the Iridaceae family. Three kinds of 1-alkyl-3-methylimidazolium ionic liquids with different alkyl chain and anion were investigated. The results indicated that ionic liquids (ILs) showed remarkable effects on the extraction yield of isoflavones. In addition, the ILUAE, including several ultrasonic parameters, such as the concentration, extraction time and solvent to solid ratio have been optimized. Under these optimal conditions (e.g., with 30 min extraction time and the solvent to solid ratio of 30 ml/g), this approach gained the highest extraction yields of tectoridin (37.45 mg/g), iristectorin B (2.88 mg/g) and Iristectorin A (5.28 mg/g). Meanwhile, tectoridin, iristectorin B and Iristectorin A in the ILUAE extract were separated and purified successfully through the high-speed counter-current chromatography (HSCCC) with a two-phase solvent system consisting of n-butanol-water (1:1, v/v). The additional advantage of this approach is that 60.21 mg tectoridin, 4.33 mg iristectorin B and 8.24 mg Iristectorin A with more than 95.0% purities have been obtained from 400 mg ILUAE extract of I. tectorum within 5 h and one-step elution under the most optimized conditions (e.g., a flow rate of 2.0 ml/min, 900 rpm and the wavelengh of 280 nm). The obtained fractions were successfully analyzed by HPLC and identified by (1)H-NMR and (13)C-NMR.

Characterization and determination of the major constituents in Belamcandae Rhizoma by HPLC-DAD-ESI-MS(n).[Pubmed:21715119]

J Pharm Biomed Anal. 2011 Sep 10;56(2):304-14.

Belamcandae Rhizoma, derived from the rhizome of Belamcanda chinensis (L.) DC., has been used as traditional Chinese medicine for the treatment of coughing and pharyngitis. However, there have been few studies dealing with the systematic analysis of the bioactive constituents in Belamcandae Rhizoma. In this work, high performance liquid chromatography-diode array detection-electrospray ionization multiple-stage mass spectrometry (HPLC-DAD-ESI-MS(n)) combined with liquid chromatography-time of flight-mass spectrometry (HPLC-TOF/MS) was established for profiling and characterization of multi-constituent in Belamcandae Rhizoma. The ESI-MS(n) fragmentation behaviors of the authentic references were proposed for aiding the structural identification of components in the extract. Thirty-five flavonoids, including 30 isoflavones and five xanthones, were identified or tentatively identified by comparing their retention times, UV and MS spectra with those of authentic compounds or literature data. Twelve of the identified compounds (neomangiferin, mangiferin, tectoridin, iristectorin B, Iristectorin A, iridin, tectorigenin, iristectorigenin A, irigenin, irisflorentin, irilone and dichtomitin) were determined by HPLC-DAD using a C(18) column. The results indicated that the developed analysis method could be employed as a rapid, effective technique for structural characterization of chemical constituents in herbal medicine. This work is expected to provide comprehensive information for the quality evaluation of Belamcandae Rhizoma, which would be a valuable reference for the further study and development of this herb and related medicinal products.