Spectrophotometric determination of manganese (II) in Sida spinosa Linn.

Abstract

Manganese  is  of  universal  occurrence  in  plant  and  has  been  identified  as   forming   metallo-enzymes   as superoxide   dismutase   ( mitochondrial),    arginase,    pyruvate    carboxylase    and    glycosyl    transferase.    It    also appears  to  be  directly  involved   in   the   enzymic  machinery   of  carbohydrates   metabolism  with   a  possible   link to  lipid  metabolism.  It  is  also  essential  for  normal   bone   structure,   reproduction  and   the   normal   functioning of central nervous system (Bhagi and Chatwal, 2003). Knowing the biological significance and uses of th is essential ultra trace metal, i t was determined spectrophotometerically  in  the  various  parts  viz;   stems,   roots,   leaves,   seeds   and   flowers   of  the   medicinal plant  Sida   spinosa   Linn.   The   method  used  is  simple,   sensitive,   selective  and  economical   which   is  based  on the oxidation  of  small  amounts  of  manganese  present  in  the  drug  either  by  potassium  peroxide  or ammonium persulphate. The former is  usually  preferred  since  it  gives  a  true  permanganate  colour.  Here manganese  converts  into  potassium  permanganate  in  acidic  solution  and  absorbance  for   the   colour   thus obtained  is  compared  with  the  concentration  absorbance  curve  of  the  various   dilutions   of   the   standard solution,  for  calculating  the   concentration   of   manganese   in   the   various   parts   of   the   plant   understudy (Peach and Tracey,  1939).  The  concentration  of  manganese  in  the  various  parts of  Sida spinosa  thus  calculated is 2.4 ppm in stems, 1.4  ppm in roots, 1.1 ppm in leaves, 3.7 ppm in seeds and 4.6 ppm in flowers.