Saliva
Using saliva
• gain knowledge
– DNA
– other genetic testing (ABO, etc)
Saliva production
• 3 pairs of glands secrete saliva into ducts
that lead to the mouth
– Sublingual (under the tongue)
– Submandibular (under the tongue)
– Parotid (below and in front of ears)
Saliva production (continued)
• Very limited quantities contributed from
mouth and pharynx
– buccal glands
– mucous glands
• Amylase
Saliva contains:
• alkaline phosphatase
• acid phosphatase
• ABO blood group antigens
• skin cells (buccal)
The Purpose!
• The purpose of saliva is lubrication for
– talking
– chewing
• helps us taste foods
– swallowing
– digestion
• initiates carbohydrate digestion via amylase
Saliva
• 1-2 LITERS of saliva for a normal adult
PER DAY!
• 0.5 ml/ minute up to 4 ml/minute!!!
Amylase
• major component of saliva
• Breaks down starch into small pieces
– As we chew up food
Starch iodine Radial Diffusion
• soluble starch is added to gel
• unknown extracts placed into holes/wells
• allowed to diffuse
Starch iodine (continued)
• If amylase is present
– hydrolyze/chew up starch
• develop by pouring iodine solution over
plates
– starch plus iodine turns BLUE
– no starch, no BLUE!
Starch iodine (continued)
• Hydrolyzed areas on the plate will remain
clear because starch has been chewed
up!
• Size of clear area allows for rough
quantitation
Soluble starch throughout plate media,
samples added to wells
As amylase allowed to “chew,” areas of hydrolyzed starch will be
larger circles around the wells
Add Iodine stain, iodine will bind with starch producing blue color. Areas where
starch has been hydrolyzed will not bind with iodine, and will therefore remain
cleared areas! Negative control/blanks should have NO clearing.
Rinse with water, measure clearing with ruler
Controls
• 1/200 known saliva standard (in water)
• 1/500 known saliva standard (in water)
• Blank
• unknown
Results
• clearing larger than 1/200 or 1/500, saliva
indicated
• smaller than 1/200 or 1/500, low levels of
amylase detected, exam for saliva
inconclusive
• no activity detected, negative for saliva
Thank You!
Thank You!