Green Synthesis of Silver Nanoparticles Using Catharanthus roseus Flower Extracts and the Determination of Their Antioxidant, Antimicrobial, and Photocatalytic Activity

Table 1

Methodology of the phytochemical analysis [20].

Phytochemical	Methodology	Expected positive color result
Carbohydrates	2 ml of extract was treated with 1 mL of Molisch’s reagent and a few drops of concentrated H2SO4 were added	Formation of purple or reddish color ring
Tannins	1 mL of extract was added to 2 mL of 5% FeCl3	Formation of dark blue or greenish-black color
Saponins	2 mL of extract and distilled water was added and shaken in a graduated cylinder for 15 minutes	Formation of 1 cm layer of foam
Terpenoids	0.5 mL of the extract was treated with 2 mL of chloroform and concentrated H2SO4	Formation of red-brown color at the interface
Anthraquinones	Few drops of 10% NH4OH were added to 1 mL of extract	Formation of a pink color precipitate
Steroids	To 1 mL of extract, an equal volume of chloroform was added and a few drops of concentrated H2SO4	Formation of a brown color ring
Proteins	To 1 mL of extract, a few drops of CuSO4 and 1 mL of 10% NaOH were added	Formation of purple or mauve color