Chapter 15: Identification of Saliva

Saliva

is largely water containing small quantities of electrolytes, proteins, antibodies, and enzymes.

**1.0–1.5 L**

The human salivary glands produce **_____** of saliva daily.

Amylases

Are enzymes that cleave polysaccharides such as starches, which are composed of D-glucose units connected by α1→4 linkages.

Amylose

consists of long, linear chains of glucose residues connected by α1→4 linkages.

Amylopectin

is highly branched and consists of linear chains of glucose residues connected by α1→4 linkages with the branch points connected by α1→6 linkages.

β-Amylases

found in plant and bacterial sources cleave only at the terminal reducing end of a polysaccharide chain.

Human α-amylases

cleave at α1→4 linkages randomly along the polysaccharide chain.

Human salivary α-amylase (HSA)

Encoded by the Amy1 locus, synthesized at the salivary glands and secreted into the oral cavity.

Human pancreatic α-amylase (HPA)

Encoded by the Amy2 locus, is synthesized by the pancreas and secreted into the duodenum through the pancreatic duct.

Iodine

is used to test for the presence of starch.

Colorimetric Assays

Dye-labeled amylase substrates such as dye-conjugated amylose or amylopectin are utilized. These substrates are not soluble in water.

buccal epithelial cells

Microscopic examination with proper histological staining can also be performed to identify the ________, indicating the presence of a saliva stain.

dark blue

The amylose in starch reacts strongly with iodine to form a _____ complex, while amylopectin develops a reddish-purple color.

reddish-purple

The amylose in starch reacts strongly with iodine to form a dark blue complex, while amylopectin develops a _____ color.

Dye-labeled amylase substrates

These substrates are not soluble in water.

RSID®-Saliva kit

Immunochromatographic Assays for Saliva

Antibody—Antigen—Antibody Sandwich

Enzyme-Linked Immunosorbent Assay (ELISA) for saliva