Page 263 - Pharmacognosy 2 PG303
P. 263

Pharmacognosy-2 (PG303)                              Level 2                Clinical Pharmacy-Pharm D

                         2- Starch granules.                    7- A single sclereid with
                                                                associated thin-walled
                                                                 parenchyma.
                        3- Fibrous sclereid from the            8- Part of a group of
                         stem base.                              sclereids.
                         4- Thick-walled parenchyma.            9- A single sclereid with
                                                                associated thickened
                                                                 walled parenchyma.
                        5- Fragments of bordered
                         pitted vessels.


              Constituents
                     Aconite root contain 3 closely allied alkaloids, aconitine, picraconitine and
              aconine. There are also very small amount of 5 other alkaloids viz., mesaconitine,
              hypaconitine, neopelline, napelline and nealine. Other constituents are starch and
              aconitic acid. The total amount of alkaloids present is 0.2-1.5%, and as much as
              2.9%. the ether soluble alkaloids, mainly aconitine, usually varies from 0.3-0.6%.
              aconitine  is  acetyl-benzoylaconine  and  is  crystalline  and  easily  soluble  in  ether.
              Picraconitine is benzoylaconine. Both picraconitine and aconine are amorphous and
              insoluble in ether and they are both much less toxic than aconitine.















































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