Topic Review Award 2 – Student Study Topic 10

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Each enzyme or microorganism has a different effect on each type of wood material, so when the tree is soaked in an enzyme-containing solution, it will have the effect of peeling the bark and layers of the wood more effectively, faster, and at the same time reducing the use of wood. up to 80% energy use. Please explain the scientific basis of this process.

Detailed explanation:

Currently, the method of peeling wood using enzyme preparations is a very effective measure and improves product quality.

Depending on the type of tree, different enzymes are used to weaken the bond between the wood and the bark and degrade the polymers of the phylogenetic layer (cellulose, carbohydrates, pectin, …).

This method not only saves significant other materials, but also saves investment in machinery, tools and 80% of electricity to peel the bark in the traditional way.


When experimenting with enzymes, a student asked the question: “In order to speed up the metabolic reaction, which method should we use effectively?”. Please answer your question and explain why.

Detailed explanation:

If you want to speed up metabolic reactions, people often use two effective methods:

  • Increasing enzyme concentration in the medium: increased enzyme concentration will bind more substrate → increased reaction rate.
  • Add to the reaction medium activators: some groups of enzymes have activators – stimulants that increase enzyme activity (helps enzyme find substrates more easily, …) → reaction rate increases go up.


Most enzymes in the body work best at about 37 degrees Celsius. At low temperatures, they still work, but more slowly. Enzymes in the gut work best at high pH, ​​while enzymes in the stomach work best at low pH because the stomach is acidic. Please indicate the right pH conditions for digestive enzyme preparations to work well in the body.


When it comes to the mechanism of action of enzymes, each enzyme can bind to a suitable substrate. When an enzyme comes into contact with a substrate, it can change to match that substrate. When the substrate is completely locked and in place, catalysis begins. Which of the above statements is true of the “lock and key” model (first introduced in 1894) and true of the induction joint model?

Detailed explanation:

What is true of the “lock and key” model:

  • Each substrate binds to a suitable substrate.
  • When the substrate is completely locked and in place, catalysis begins.

What is true for the inductive joint model:

  • When an enzyme comes into contact with a substrate, it can change to match that substrate.


Pectinase enzyme is a group of pectin hydrolysing enzymes widely used in the beverage industry. The products of pectin hydrolysis are galacturonic acid, galactose, arabinose, methanol, etc. Putting pectinase in the crushing stage will increase efficiency. The juice yield after squeezing is up to 15 – 25%. Pectin in the fruit tissue makes the crushed fruit mass will have a colloidal state, so the juice cannot escape when pressed. Thanks to pectinase, it breaks down the pectin substrates, making the extract in the cell fluid easier to escape, increasing the extraction efficiency. Explain why the juice is transparent, not cloudy, and easier to filter.

Detailed explanation:

Pectin is a polysaccharide in nature. Pectin has two forms: insoluble form, which exists mainly in the cell wall and soluble form, which is abundant in fruit juice.

The enzyme pectinase is applied in the beverage industry thanks to its ability to hydrolyze pectin in both forms:

– Pectin in the hydrolyzed cell wall will make fruit crushing easier because the cell wall is less stable.

– Pectin in hydrolyzed fruit juice will make the juice clearer and more beautiful → bringing high economic efficiency to the beverage industry.

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