What is the Difference Between Liver Bile and Gallbladder Bile

The main difference between liver bile and gallbladder bile is that the pH of liver bile is 8-8.6, whereas the pH of gallbladder bile is 7-7.6.

Liver bile and gallbladder bile are two bile types. They vary by their location. Importantly, the liver produces bile and secretes through the hepatic duct to the gallbladder.

Key Areas Covered

1. What is Liver Bile
– Definition, Facts, Features
2. What is Gallbladder Bile
– Definition, Facts, Features
3. Similarities Between Liver Bile and Gallbladder Bile
– Outline of Common Features
4. Difference Between Liver Bile and Gallbladder Bile
– Comparison of Key Differences
5. FAQ: Liver Bile and Gallbladder Bile
– Answers to frequently asked questions

Key Terms  

Gallbladder Bile, Liver Bile

What is Liver Bile

Liver bile is a secretion of the liver. It is a dark green to yellowish-brown color fluid. The liver produces bile continuously, which flows out through the left and right hepatic ducts to the common bile duct. However, the release of this bile to the small intestine only occurs after eating. When food is unavailable in the digestive system, hepatic bile travels into the gallbladder for storage.

Figure 1: Liver Bile

Furthermore, bile is responsible for the emulsification of lipids, which aids digestion. Hence, it serves as a surfactant. Bile salts are responsible for this, and the anions of bile salts have both hydrophilic and hydrophobic ends. Thus, they aggregate around the lipid droplets, forming micelles. This increases the surface area for the enzymatic action of pancreatic lipase on lipids.

In addition to the action in digestion, bile serves as a route of excretion for the endogenous and exogenous substances from the blood and liver, including bilirubin, a by-product of the destruction of red blood cells. On the other hand, the bile in the common bile duct is alkaline (pH 7.50-8.05), and it neutralizes the acidic pH of the chyme. In addition, bile salts are bacteriocides that destroy microorganisms in the food. 

What is Gallbladder Bile

Gallbladder bile is the storage form of the hepatic bile. The main function of the gallbladder is to store, concentrate, and acidify the hepatic bile. It releases bile to the common bile duct when food is available in the digestive system. After eating, the gallbladder releases bile to the common bile duct through the cystic duct.

Figure 2: Gallbladder

When hepatic bile enters the gallbladder, it is concentrated and acidified. The gallbladder bile contains 97% water, 0.7% bile salts, 0.2% bilirubin, 0.51% fats (cholesterol, fatty acids, and lecithin), and 200 mEq/l inorganic salts. The pH of the gallbladder bile is 6.80-7.65.  

Similarities Between Liver Bile and Gallbladder Bile

• Liver bile and gallbladder bile are two bile types produced by the body.
• They are aqueous solutions.
• Bile salts, cholesterol, phospholipids, conjugated bilirubin, electrolytes, and water are the main components of bile.  

Difference Between Liver Bile and Gallbladder Bile

Definition

Liver bile refers to a fluid that is made and released by the liver and stored in the gallbladder. Meanwhile, gallbladder bile refers to the bile stored in the gallbladder.  

pH of the Bile

The pH of liver bile is 8-8.6, while the pH of gallbladder bile is 7-7.6.

Specific Gravity

The specific gravity of liver bile is 1010-1011, while the specific gravity of gallbladder bile is 1026-1032. 

Water Content

The water content of liver bile is 97.6%, while the water content of gallbladder bile is 89%.

Solids

Solids are 2.4% in liver bile, while solids are 11% in gallbladder bile.

Bile salts and Bile Pigments

Bile salt content is 0.5 g/dl, and bile pigment content is 0.05g/dl in liver bile, while bile salt content is 6.0g/dl and bile pigment content is 0.3g/dl in gallbladder bile. 

FAQ: Liver Bile and Gallbladder Bile

What is the difference between the liver and gallbladder? 

The liver produces bile, the solution responsible for the digestion of fat. In comparison, the gallbladder is the organ that stores bile. It squeezes bile into the small intestine through the bile duct after entering fatty food.  

What does the liver and gallbladder bile do? 

Bile has two functions in the body. It facilitates lipid absorption and digestion. Also, it helps to eliminate waste products from the body.

What are the two types of bile? 

Cholic acid and chenodeoxycholic acid (CDCA) are the two bile salts. Cholic acid is a trihydroxylated bile, while chenodeoxycholic acid is a dihydroxy bile salt.

Conclusion

In brief, liver bile and gallbladder bile are two bile types produced by the liver. Water, bile salts, cholesterol, phospholipids, conjugated bilirubin, and electrolytes are the main components of the bile. The pH of liver bile is 8-8.6. In contrast, the pH of gallbladder bile is 7-7.6. Therefore, the main difference between liver bile and gallbladder bile is pH. 

References:

1. Hundt M, Basit H, John S. Physiology, Bile Secretion. [Updated 2022 Sep 26]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-.

Image Courtesy:

1. “GallbladderAnatomy-en” By GallbladderAnatomy.png – Own Work (CC-BY SA 3.0) via Commons Wikimedia
2. “Diagram showing the position of the liver and the gallbladder CRUK 351” By Cancer Research UK – Own Work (CC-BY SA 4.0) via Commons Wikimedia