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Clinical pharmacy PharmD program                     Third level                          Phytochemistry-1 (PG-504)


              •  Sweetness:

                Sucrose can be considered as the base of measuring the sweetness of different

                sugars and other materials:



                            Substance   Degree of sweetness   Remarks

                             Sucrose                 100                Standard

                             D-Glucose               74.3               Less sweet

                             D-Fructose             173.3              The sweetest

                             Invert                  123                sweeter          than
                         sugar                                       sucrose

                             Lactose                   16               Very less sweet



              •  The sweetest of the natural monosaccharide is fructose

              •  It can be fermented by invertase.


              •  It  is  a  non-reducing;  i.e.,  cannot  reduce  Fehling’s  reagent,  cannot  form  an

                osazone.

              Fermentation:


              •  Sucrose  and  maltose  can  be  fermented  when  yeast  is  added  because  yeast

                contains the enzymes:  invertase and maltase.

              •  Lactose will not ferment because yeast does not contain lactase.

              Chemical tests:



                1) It gives permanent violet color with solution of cobalt nitrate in presence
                   of sodium hydroxide.


                2) It gives red color with resorcinol in presence of HCl.
              Uses:



                1) Preparation of syrups.

                2) Nutrient and demulcent.

                3) In high concentration, as preservative.

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