Detection of Salivary Amylase Activity (Amylase Test)

Theoretical Background / Context

• Salivary amylase, formerly known as ptyalinis, is a glucose-polymer cleavage enzyme that is produced by the salivary glands, breaking down starch into maltose and isomaltose. 
• Amylase, like other enzymes, works as a catalyst. Enzymes and catalysts both affect the rate of a reaction. 
• In fact, all known enzymes are catalysts, but not all catalysts are enzymes. 
• The difference between catalysts and enzymes is that enzymes are largely organic in nature and are bio-catalysts, while non-enzymatic catalysts can be inorganic compounds. 
• Neither catalysts nor enzymes are consumed in the reactions they catalyze. It comprises a small portion of the total amylase excreted, which is mostly made by the pancreas. 
• Amylases digest starch into smaller molecules, ultimately yielding maltose, which in turn is cleaved into two glucose molecules by maltase. 
• Starch comprises a significant portion of the typical human diet for most nationalities. 
• Given that salivary amylase is such a small portion of total amylase, it is unclear why it exists and whether it conveys an evolutionary advantage when ingesting starch.
• Enzymes are proteinaceous in nature and catalyze chemical reactions in biochemistry. 
• Enzymes are responsible for speeding up reactions and mostly synthesized in living cells. 
• A study of enzymatic hydrolysis of starch through amylase testing will give knowledge about specific reactions of enzymes. 
• There are several factors, like temperature and pH, that affect the reaction in the amylase test.
• At higher temperatures, the enzymes are denatured, while at lower temperatures, the enzymes are deactivated, so it takes more time at low and high temperatures to digest the starch. 
• At optimum temperature (32–37 C), the enzyme is active and therefore consumes less time for starch digestion.

What Does Amylase Test For? This amylase test evaluates the enzyme's ability to break down polysaccharides under various conditions.

Principle of Work

• Optimal activity for most of the enzymes is generally observed between pH 5.0 and 9.0. 
• However, a few enzymes, e.g., pepsin, are active at pH values well outside this range. 
• Above and below this range, the reaction rate reduces as enzymes get desaturated. 
• Amylase is the hydrolytic enzyme that breaks down many polysaccharides like starch, amylose, and dextrins and yields a disaccharide, i.e., maltose, as demonstrated in the amylase test.
• The  amylase substrate in this amylase lab is soluble starch, which gives a blue-black color with I2 solution. 
• The resultant digestion products can cause color changes in the iodine solution.