Heating Bromelain produces many changes in its structure and activity. Pure Bromelain Powder is a natural protease derived from the pineapple plant. It is found mainly in the fruit, stem, and leaves of pineapple. Bromelain is mainly composed of a variety of proteases with the ability to hydrolyze large protein molecules. It is widely used in food processing, pharmaceutical, health care, and cosmetic industries. Its main catalytic effect is to induce protein degradation by cutting the protein molecular chain at the active site of specific amino acid residues. Specific changes can be described in terms of thermal stability, catalytic ability, structural damage, and other aspects of proteases.
Structure
The structure of bromelain is relatively complex, consisting of multiple subunits, of which the main active site is usually located in the structural core of its enzyme. The enzymatic activity of pineapple protease is closely related to its three-dimensional structure, and any change that damages its structure will harm the enzymatic activity. Bromelain contains several catalytic sites. Its activity is closely related to the spatial arrangement of amino acid residues, hydrogen bonding and hydrophobic interactions within the enzyme molecule.
Effect of heating on protease
The effects of heating on pineapple protease are mainly reflected in the following aspects.
• Denaturation of protein
Heating leads to the disruption of hydrogen bonding and hydrophobic interactions within the protein molecule. This leads to a change in the protein from its natural three-dimensional structure to an irregular linear or partially folded state. This process is called denaturation. Bromelain may undergo denaturation during heating due to more non-covalent bonds in its structure. This leads to a change in its active center and hence loss of catalytic activity.
• Effect of temperature on enzyme activity
In general, enzyme activity is closely related to temperature. At lower temperatures, enzyme activity is lower. However, when heated to a certain temperature, the catalytic reaction of the enzyme speeds up. However, the stability of protease gradually decreases with increasing temperature. Once the temperature exceeds its thermal stability threshold, the protease will begin to lose its catalytic activity. Bromelain protease has a relatively low thermal stability, usually between 45°C and 50°C. Its activity gradually decreases and when the temperature exceeds 65°C, the activity of bromelain is almost completely lost.
• Loss of enzyme activity after thermal denaturation
When heated beyond the thermal limit of Pure Bromelain Powder, the three-dimensional structure of the enzyme undergoes severe denaturation. This results in the loss of its catalytic site or a significant reduction in its activity. This denaturation may be irreversible and the enzyme cannot return to its original active state even after the temperature is lowered.
Mechanism of enzyme inactivation
The main mechanisms of inactivation of bromelain include the following:
- Structural damage:
High temperature destroys the non-covalent bonds such as hydrogen bonds and hydrophobic interactions of the protein. This loses the original spatial structure.
- Alteration of the catalytic site:
Conformational changes in the active center of the enzyme prevent the substrate from binding to the active site, which in turn leads to loss of enzyme activity.
- Exposure of hydrophobic regions:
High temperatures expose the hydrophobic regions within the protease to the solution. This can lead to self-aggregation or precipitation of the enzyme molecules, further exacerbating its inactivation.
Effect of heating at different temperatures
The thermal stability of bromelain enzyme powder depends on the temperature and time of heating. The following are the effects of heating at different temperatures.
• Low-temperature heating (40°C-50°C)
In this temperature range, the enzyme activity of bromelain decreases gradually but still maintains some activity. The structural change of the enzyme is small in this temperature range and the main reason for the gradual decrease in activity is the slight loss of folding of the amino acid residues in the enzyme molecule.
• Medium temperature heating (50℃-70℃)
In this temperature range, the activity of pure bromelain powder decreases sharply. At temperatures above 50°C, the denaturation of the protease is accelerated and the spatial structure of the catalytic center changes considerably. Although in some cases the denaturation is reversible. However, in most cases, too high a temperature leads to irreversible inactivation of the enzyme.
• Heating at high temperatures (over 70°C)
When the temperature exceeds 70°C, bromelain undergoes severe thermal denaturation, and the enzyme activity is almost completely lost. In this case, the structural damage within the enzyme molecule is irreversible. This may occur with aggregation and precipitation of the enzyme molecules.
Factors affecting the thermal denaturation of bromelain enzyme
When heated, the thermal stability of bromelain is affected not only by temperature but also by the following factors.
• pH value
The thermal stability of bromelain varies under different pH conditions. Usually, in the weakly acidic to neutral pH range, the thermal stability of bromelain is better. While under extreme acidic or alkaline conditions, the enzyme is less stable and prone to denaturation during heating.
• Lonic Strength
Changes in ionic strength can also affect the thermal stability of pure bromelain powder. Higher salt concentrations may alter the structure of the enzyme. This affects its stability to heat.
• Source of protease
Different sources of pineapple protease have different thermal stability. For example, pineapple proteases derived from pineapple stems are usually more heat resistant. Bromelain from pineapple fruit is relatively less heat resistant. Guanjie Biotech's bromelain is derived from pineapple stems. Our product is heat resistant.
Applications
• Impact on the food industry
Bromelain is mainly used in the food industry as a natural meat tenderizer. Since heat causes loss of enzyme activity, it is necessary to control the temperature when using pineapple protease for meat tenderisation and to avoid excessive temperatures. A temperature range of 30-50°C is usually recommended to ensure maximum activity of bromelain.
• Impact on the pharmaceutical sector
Bromelain powder bulk is also widely used in the pharmaceutical, especially in anti-inflammatory and anti-tumor treatments. Inactivation of the enzyme during heating may affect its pharmacological activity. Therefore, when preparing the drug, the heating conditions need to be controlled to ensure its biological activity.
• Effects in cosmetics
Bromelain bulk powder is used in cosmetics mainly in exfoliating and anti-aging products. The effect of heating on the enzyme also needs to be considered, as too high temperatures may cause the enzyme to fail, thus affecting the effectiveness of the product.
The effects of heating on bromelain are mainly in the denaturation and inactivation of the enzyme as well as structural changes. To maintain its activity in practical applications, the heating temperature and time need to be precisely controlled to avoid irreversible damage caused by excessive temperatures.
Guanjie Biotech specializes in supplying high-quality bulk Bromelain powder. Our Bromelain enzyme powder features a light gray appearance and achieves 98% purity, ensuring exceptional quality. The powder is finely processed to pass through an 80-mesh sieve, guaranteeing uniform particle size and consistency. To ensure precise and reliable results, we utilize the GDU method for testing its enzymatic activity. If you are seeking pure bromelain powder for your production or research needs, Guanjie Biotech is your trusted partner. We take pride in delivering products that meet rigorous standards for purity and effectiveness. For more information or inquiries, please feel free to contact us at info@gybiotech.com.
