Alpha-Cyclodextrin

Milano F, et al. Food Bioscience, 2025, 68, 106768.

This study investigates the experimental use of alpha-cyclodextrin (α-CD) as a stabilizing agent for bioactive-rich tomato oil (TO) extracted via supercritical CO₂ (SC-CO₂), a solvent-free, sustainable method. Emulsions were prepared using α-, β-, and γ-cyclodextrins at high oil volume fractions (φ = 60–75%). Notably, only α-CD produced gel-like, stable emulsions at φ ≤ 70%, with φ = 60% yielding optimal characteristics—high viscosity, reduced phase separation, and minimized droplet size and coalescence, as revealed by confocal microscopy. Thermal (50 °C) and UV-C exposure tests were conducted to evaluate the emulsions' ability to preserve carotenoids and tocopherols. Compared to bulk TO, α-CD emulsions significantly enhanced carotenoid stability under heat and extended the photostability of both carotenoids and tocopherols under UV-C exposure for up to 9 hours. Further emulsion systems were recreated using α-CD and synthetic glyceryl trioctanoate (GTO), calibrated to match lycopene and α-tocopherol concentrations in TO.

Chen L, et al. Food Chemistry, 2025, 473, 143135.

Alpha-cyclodextrin (α-CD) was employed to encapsulate chlorine dioxide (ClO₂) gas molecules via a direct inclusion complexation strategy, enabling the formation of ClO₂@α-CD complexes with enhanced stability and sustained-release properties. This formulation significantly improves the safe storage and controlled release of ClO₂, a volatile yet potent antimicrobial agent.

The ClO₂@α-CD inclusion complex was synthesized using a saturated solution coprecipitation method. Specifically, 7.35 g of α-CD was dissolved in 25 mL of high-purity distilled water (18.2 MΩ·cm) and maintained at 40 °C under constant stirring to achieve saturation. Subsequently, 1 g of ClO₂ effervescent tablet powder was introduced into the system under sealed conditions, with the mixture stirred at 500 rpm for 30 minutes. This facilitated the formation of ClO₂ inclusion within the α-CD cavity. The mixture was then subjected to refrigeration at 4 °C for over 12 hours to promote full precipitation. The resulting solid was isolated through vacuum filtration, thoroughly washed with anhydrous ethanol (99.5 wt%) to remove surface impurities, and dried in a dark, moisture-controlled environment at 22 °C for 12 hours. The final ClO₂@α-CD complex was sealed and stored at −18 °C to preserve its integrity.

Lu Y, et al. Journal of Colloid and Interface Science, 2025, 691, 137352.

Alpha-cyclodextrin (α-CD) was employed as a surface modifier in the hydrothermal synthesis of sulfur quantum dots (CD-S dots), which were subsequently utilized as photocatalysts for dehydrogenative cross-coupling of alcohols and amines to generate imines under visible light. The synthesis procedure involved dissolving sublimation sulfur powder (1.4 g) and α-CD (3.0 g) in 50 mL of 2.0 M aqueous NaOH. The mixture was sealed in a 200 mL Teflon-lined autoclave and subjected to hydrothermal treatment at 150 °C for 6 hours. Upon cooling to room temperature, the resulting CD-S dots were collected and stored under refrigerated conditions. These α-CD-modified sulfur quantum dots exhibited high catalytic activity in promoting oxidative coupling reactions, leveraging their visible-light responsiveness.

Czapnik P, et al. Journal of Molecular Structure, 2025, 1320, 139671.

This study demonstrates the use of alpha-cyclodextrin in the synthesis of inclusion complexes with p-aminobenzoic acid (PABA) and nicotinic acid (NIK), emphasizing its role as a host molecule for complexation in aqueous systems. In the preparation of the PABA complex, equimolar quantities of alpha-cyclodextrin (0.1 mmol, 0.0972 g) and PABA (0.1 mmol, 0.0137 g) were independently dissolved in water (4 mL each). The PABA solution was introduced dropwise into the alpha-cyclodextrin solution, followed by continuous stirring at 70 °C for 2 hours. Crystallization occurred upon standing at ambient temperature, yielding colourless inclusion complex crystals.

For the NIK inclusion complex, both alpha-cyclodextrin and NIK were pre-treated via ball milling for 5 minutes to enhance their solubility and reactivity. Alpha-cyclodextrin (0.1 mmol) was subsequently dissolved in water (3 mL), while NIK (0.1 mmol, 0.0123 g) was dissolved in ethanol (3 mL). The NIK solution was then added to the aqueous cyclodextrin solution and stirred for 1 hour at room temperature. Crystallization was achieved by storing the mixture at 2 °C in an ice bath, resulting in the formation of colourless crystals.

Smits M. M., et al. Food Chemistry, 2024, 460, 140759.

Alpha-Cyclodextrin (α-CD) was experimentally evaluated for its ability to stimulate glucagon-like peptide-1 (GLP-1) secretion and improve metabolic parameters across multiple models. In vitro, α-CD was applied to GLUTag enteroendocrine cells, where it dose-dependently enhanced GLP-1 secretion by up to 170%. This effect was mechanistically linked to adenylyl cyclase activation, phospholipase C signaling, and L-type calcium channel influx, indicating a complex intracellular regulatory pathway.

Ex vivo studies utilizing isolated perfused rat colons demonstrated that luminal administration of α-CD led to a 20% increase in GLP-1 secretion, confirming its activity within intestinal tissue. In vivo, lean mice received daily oral doses of α-CD, resulting in significant body weight reduction and attenuated peak glycemia during oral glucose tolerance testing (OGTT), compared to saline controls. In a high-fat diet-induced obese mouse model, dietary inclusion of α-CD induced weight loss comparable to cellulose-treated controls but uniquely reduced food intake, suggesting appetite modulation. Despite these changes, glucose, insulin, and GLP-1 levels during OGTT remained unchanged between groups.