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1.
J Chromatogr Sci ; 44(5): 239-43, 2006.
Article in English | MEDLINE | ID: mdl-16774707

ABSTRACT

High-performance liquid chromatography (HPLC) with diode array detection interfaced to electrospray ionization (ESI) mass spectrometry (MS) is applied to identify the two epimers of a novel and minor constituent, podophyllotoxin-4-O-(D)-6-acetylglucopyraniside from high-altitude Podophyllum hexandrum for the first time. This is done by matching the structural information from the tandem MS data with the reported lignan markers. The results show that LC-MS-MS is the method of choice for fast detection and detailed chemical analysis of mixtures in the crude extracts of Podophyllum. The method can be employed in the absence of reference standards for the markers and is particularly useful in view of the scarcity of these rare chemical standards.


Subject(s)
Chromatography, Liquid/methods , Glucosides/chemistry , Podophyllotoxin/analogs & derivatives , Podophyllum/chemistry , Spectrometry, Mass, Electrospray Ionization/methods , Tandem Mass Spectrometry/methods , Podophyllotoxin/chemistry
2.
J Chromatogr Sci ; 44(4): 177-80, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16620514

ABSTRACT

St. John's Wort (Hypericum perforatum), a perennial flowering plant, has been used medicinally for thousands of years and has most recently been identified as an effective treatment for mild to moderate depression and neuralgic disorders. This work presents a procedure for the isolation of naphthodianthrones from St. John's Wort by an accelerated extraction and separation of marker compounds by preparative high-performance liquid chromatography (HPLC) with photodiode array detection. The accelerated extraction method minimizes the extraction time and increases the yield, and the marker compounds obtained by preparative HPLC are of 98% purity. The compounds are characterized by liquid chromatography-mass spectrometry (electrospray ionization) and NMR spectra.


Subject(s)
Anthracenes/isolation & purification , Chromatography, High Pressure Liquid/methods , Hypericum/chemistry , Magnetic Resonance Spectroscopy
3.
J Chromatogr Sci ; 43(7): 348-50, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16176645

ABSTRACT

The present work describes the isolation of camptothecin and 9-methoxycamptothecin from the aerial parts of Nothapodytes foetida by semipreparative high-performance liquid chromatography because the separation of compounds by conventional procedures is tedious and cumbersome. The purity of the isolates is determined by physicochemical data and liquid chromatography-mass spectrometry.


Subject(s)
Camptothecin/analogs & derivatives , Camptothecin/isolation & purification , Chromatography, High Pressure Liquid/methods , Magnoliopsida/chemistry , Chromatography, Liquid/methods , Mass Spectrometry/methods
4.
J Chromatogr Sci ; 43(10): 530-1, 2005.
Article in English | MEDLINE | ID: mdl-16438794

ABSTRACT

Three methods commonly used for the extraction of bioactive molecules from natural plant material are compared. Dried Hypericum perforatum L. plant material is subjected to Soxhlet extraction, extraction by ultrasonication, and accelerated solvent extraction. The percentage of two bioactive compounds, hyperforin and hypericin, in the extracts is used as a parameter for comparison of the extraction procedure.


Subject(s)
Hypericum/chemistry , Chromatography, High Pressure Liquid/methods , Spectrophotometry, Ultraviolet
5.
J Chromatogr Sci ; 41(8): 444-6, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14558939

ABSTRACT

The present work describes isolation of bioactive lipophilic constituent [namely, hyperforin from St. John's wort (Hypericum perforatum L.)], of approximately 98% purity by semipreparative high-performance liquid chromatography (LC). The extraction, isolation, and analysis of the collected compound is performed without the use of antioxidants and inert gas atmospheres at all the stages. Hyperforin, separated isocratically on a 12microm semiprep column, is obtained in high purity, lyophilized after the removal of the organic phase, and preserved at a low temperature. The purity of the collected marker compound is estimated by the use of LC-mass spectrometry and spectroscopic techniques.


Subject(s)
Chromatography, High Pressure Liquid/methods , Hypericum/chemistry , Plant Extracts/chemistry , Terpenes/isolation & purification , Bridged Bicyclo Compounds , Mass Spectrometry , Phloroglucinol/analogs & derivatives , Reproducibility of Results
6.
Neurol India ; 49(1): 84-6, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11303250

ABSTRACT

A 37 year old male presented with left hemiplegia, left below knee amputation, right partial foot amputation and claudication pain. The limitations in the rehabilitation management in such a high-risk patient are multiplied. The appreciable benefits from supervised rehabilitation and judicious goal setting can help in improving the functional status and retard the disease progression in such patients. This study highlights that coexisting cerebrovascular, coronary and peripheral vascular diseases can pose a real challenge and can result in multiple disabilities.


Subject(s)
Coronary Disease/rehabilitation , Hemiplegia/rehabilitation , Infarction, Middle Cerebral Artery/rehabilitation , Peripheral Vascular Diseases/rehabilitation , Adult , Amputation, Surgical , Humans , Male , Peripheral Vascular Diseases/surgery
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