Ziba  Gholamhosseinpour, Khodayar  Hemati, Hamidreza  Dorodian, Zeinolabedin  Bashiri-Sadr, 
    Effect of Nitrogen Fertilizer on Yield and Amount of Alkaloids in Periwinkle and Determination of Vinblastine and Vincristine by HPLC and TLC,
    Plant Sciences Research,
    Volume 3,Issue 2,
    2011,
    Pages 4-9,
    ISSN 1995-476x,
    psres.2011.4.9,
    (https://makhillpublications.co/view-article.php?doi=psres.2011.4.9)
    Abstract: Periwinkle (<I>Catharanthus roseus</I> L.) is a most important 
  medicinal plant which is a rich source of bioactive compounds such as alkaloids. 
  The purpose of the present study was to investigate the effect of various concentrations 
  of nitrogen on content and yield of alkaloids in periwinkle. This study showed 
  that there were significant differences among various concentrations of nitrogen 
  in all measured parameters except the fresh and dry weight of shoot tips. The 
  results indicated that the fresh and dry weight of total foliage of periwinkle 
  increased with increasing the amount of nitrogen fertilization from 0-100 kg 
  N ha<SUP>-1</SUP> and then decreased at 150 kg N ha<SUP>-1</SUP>. The alkaloids 
  of vinblastine and vincristine were measured by HPLC and TLC assays. The highest 
  content and yield of vinblastine was observed in 150 kg N ha<SUP>-1</SUP> while 
  the lowest content and yield of vincristine was found in 150 kg N ha<SUP>-1</SUP> 
  by both methods of assessment. The results also showed that the content and 
  yield of vinblastine and vincristine quantified with HPLC assay was higher than 
  the samples determined by TLC method. The results provided important information 
  of nitrogen effect on yield and alkaloid content of plant for commercial production 
  of periwinkle.
    Keywords: HPLC;alkaloid;nutrient element;Periwinkle;TLC;Iran