Pectin extraction from lime pomace by cold-active polygalacturonase-assisted method.

Area of Science:

• Biotechnology
• Enzymology
• Food Science

Background:

• Pectin extraction typically requires high temperatures, increasing energy costs and potentially degrading pectin quality.
• Developing cold-active enzymes for industrial applications can lead to more sustainable and efficient bioprocesses.

Purpose of the Study:

• To characterize a polygalacturonase enzyme from Antarctic yeast for pectin extraction.
• To evaluate the feasibility of using this enzyme for pectin isolation from lime pomace at low temperatures.

Main Methods:

• Cultivation of Antarctic yeast (Tausonia pullulans 8E) to produce polygalacturonase.
• Biochemical characterization of the enzyme's activity, optimum temperature, pH, stability, and inhibition.
• Enzymatic-assisted pectin extraction from lime pomace at 20°C.
• Pectin characterization including yield, uronic acid and neutral sugar content, molecular weight, and sugar linkage analysis.

Main Results:

• The yeast extract exhibited polygalacturonase activity with an optimum temperature of 40°C and pH of 5.0, retaining 54% activity at 20°C.
• The enzyme demonstrated good pH-stability and thermostability, with notable inhibition by Hg+2 and Co+2.
• Pectin was successfully extracted from lime pomace at 20°C with a 15% yield in 120 minutes.
• The extracted pectin contained 46% uronic acid, 53% neutral sugars, and had a molecular weight of approximately 100,000 g mol⁻¹.

Conclusions:

• The cold-active polygalacturonase from Tausonia pullulans 8E is effective for pectin extraction at low temperatures.
• This enzymatic approach offers a sustainable alternative for pectin production, enabling the creation of low-calorie gels.