What is saliva composed of?

Question

Like water and............?

Answer 1

Best Answer - Chosen by Voters

Saliva is 98% water, but it contains many important substances, including electrolytes, mucus, antibacterial compounds and various enzymes.

It is a fluid containing:

Water
Electrolytes:
2-21 mmol/L sodium (lower than blood plasma)
10-36 mmol/L potassium (higher than plasma)
1.2-2.8 mmol/L calcium
0.08-0.5 mmol/L magnesium
5-40 mmol/L chloride (lower than plasma)
25 mmol/L bicarbonate (higher than plasma)
1.4-39 mmol/L phosphate
Mucus. Mucus in saliva mainly consists of mucopolysaccharides and glycoproteins;
Antibacterial compounds (thiocyanate, hydrogen peroxide, and secretory immunoglobulin A)
Various enzymes. There are three major enzymes found in saliva.
α-amylase. Amylase starts the digestion of starch and lipase fat before the food is even swallowed. It has a pH optima of 7.4.

lysozyme. Lysozyme acts to lyse bacteria.

lingual lipase. Lingual lipase has a pH optimum ~4.0 so it is not activated till entering an acidic environment.

Minor enzymes include salivary acid phosphatases A+B, N-acetylmuramyl-L-alanine amidase, NAD(P)H dehydrogenase-quinone, salivary lactoperoxidase, superoxide dismutase, glutathione transferase, class 3 aldehyde dehydrogenase, glucose-6-phosphate isomerase, and tissue kallikrein.
Cells: Possibly as much as 8 million human and 500 million bacterial cells per mL. The presence of bacterial products (small organic acids, amines, and thiols) causes saliva to sometimes exhibit foul odor.
Opiorphin, a newly researched pain-killing substance found in human saliva.

Source(s):

wikipedia

Answer 2

Salivase, a digestive enzyme which breaks sugars (carbohydrates) down on their way to the stomach.

Salive also has a higher than 7 ph so it is alkaline, helping to fight the acid produced by plaque which causes cavities.

Answer 3

"like water..." well, that's certainly most of it 98% or so. The Wikipedia article looks pretty good to me: http://en.wikipedia.org/wiki/Saliva

Answer 4

Saliva is 98% water, but it contains many important substances, including electrolytes, mucus, antibacterial compounds and various enzymes.
Hear is a list of substances found in saliva:
* Water
* Electrolytes:
o 2-21 mmol/L sodium (lower than blood plasma)
o 10-36 mmol/L potassium (higher than plasma)
o 1.2-2.8 mmol/L calcium
o 0.08-0.5 mmol/L magnesium
o 5-40 mmol/L chloride (lower than plasma)
o 25 mmol/L bicarbonate (higher than plasma)
o 1.4-39 mmol/L phosphate
* Lubricating Mucus. Mucus in saliva mainly consists of mucopolysaccharides and glycoproteins;
* Antibacterial compounds (thiocyanate, hydrogen peroxide, and secretory immunoglobulin A)
* Various enzymes. There are three major enzymes found in saliva.
o α-amylase (EC3.2.1.1). Amylase starts the digestion of starch and lipase fat before the food is even swallowed. It has a pH optima of 7.4.
o lysozyme (EC3.2.1.17). Lysozyme acts to lyse bacteria.
o lingual lipase (EC3.1.1.3). Lingual lipase has a pH optimum ~4.0 so it is not activated till entering an acidic environment.
o Minor enzymes include salivary acid phosphatases A+B (EC3.1.3.2), N-acetylmuramyl-L-alanine amidase (EC3.5.1.28), NAD(P)H dehydrogenase-quinone (EC1.6.99.2), salivary lactoperoxidase (EC1.11.1.7), superoxide dismutase (EC1.15.1.1), glutathione transferase (EC2.5.1.18), class 3 aldehyde dehydrogenase (EC1.2.1.3), glucose-6-phosphate isomerase (EC5.3.1.9), and tissue kallikrein (EC3.4.21.35).
* Cells: Possibly as much as 8 million human and 500 million bacterial cells per mL. The presence of bacterial products (small organic acids, amines, and thiols) causes saliva to sometimes exhibit foul odor.
* Opiorphin, a newly researched pain-killing substance found in human saliva.

Source(s):

Radan MD, PhD