Gamma-cyclodextrin production using cyclodextrin glycosyltransferase from Bacillus clarkii 7364

Area of Science:

• Biotechnology
• Enzymology
• Carbohydrate Chemistry

Background:

• Cyclodextrins (CDs) are cyclic oligosaccharides with diverse applications.
• Cyclodextrin glycosyltransferase (CGTase) is crucial for CD production.
• Optimizing CGTase activity and product selectivity is key for industrial applications.

Purpose of the Study:

• To investigate the production of cyclodextrins (CDs) using CGTase from Bacillus clarkii 7364.
• To enhance the conversion rate and selectivity towards gamma-cyclodextrin (γ-CD).
• To explore the feasibility of industrial-scale γ-CD production.

Main Methods:

• Enzymatic reaction using CGTase from Bacillus clarkii 7364.
• Utilized soluble starch as a substrate in a specific buffer (0.025 M sodium phosphate-NaOH, pH 12).
• Optimized reaction parameters including enzyme concentration (5 U/g starch), substrate concentration (15% w/v), temperature (55 °C), and the presence of glycyrrhizic acid (2% w/v).

Main Results:

• Achieved a 47% (w/w) conversion rate to γ-CD.
• Obtained a high γ:β-CD ratio of 89:11, with minimal α-CD formation.
• Demonstrated a significant increase in overall CD production and marked selectivity for γ-CD.

Conclusions:

• The optimized enzymatic process significantly enhances γ-CD production and selectivity.
• The use of Bacillus clarkii 7364 CGTase with glycyrrhizic acid offers a commercially attractive method for industrial γ-CD synthesis.
• The findings provide a scalable and efficient approach for producing high-purity γ-CDs.