Multifunctional Chitosan/Mn(II) Complexes: Preparation, Catalytic Activity in Imine Synthesis and Aldol Reaction, and
Roman A Golubev1,2, Andrey A Nikolaev1, Daria I Semenkova1,2
1Department of Human Ecology and Bioelementology, RUDN University, 6 Miklukho-Maklaya St., Moscow 117198, Russia.
Molecules (Basel, Switzerland)
|December 11, 2025
Summary
Chitosan-manganese(II) nanoparticles show high catalytic activity for organic reactions and accelerate milk fermentation. The optimal 1:2 ratio enhances fermentation and extends shelf life by inhibiting post-acidification.
Area of Science:
- Materials Science
- Catalysis
- Food Science
Background:
- Chitosan-manganese(II) complexes offer potential as catalysts.
- Developing efficient and reusable catalysts is crucial for sustainable chemistry.
- Optimizing nanoparticle synthesis for specific applications is an ongoing challenge.
Purpose of the Study:
- To synthesize and characterize chitosan-manganese(II) nanoparticles.
- To evaluate their catalytic activity in organic synthesis and food applications.
- To determine the optimal molar ratio for desired functionalities.
Main Methods:
- Synthesis of chitosan-manganese(II) nanoparticles in various molar ratios (1:2, 1:1, 2:1).
- Characterization using dynamic light scattering, electrophoretic light scattering, X-ray diffraction, SEM, FTIR, and thermal analysis.
- Assessment of catalytic activity in benzylamine oxidative coupling and aldol reactions, and in accelerating milk fermentation by Streptococcus thermophilus.
Main Results:
- Chitosan-manganese(II) nanoparticles (1:1 ratio) exhibited high catalytic activity in green solvents for imine formation and aldol reactions.
- The catalyst demonstrated reusability over ten cycles without significant loss of activity.
- The 1:2 ratio of chitosan-manganese(II) complexes effectively accelerated milk fermentation and extended shelf life by inhibiting post-acidification.
Conclusions:
- Chitosan-manganese(II) nanoparticles are effective heterogeneous catalysts for organic synthesis and food processing.
- The 1:2 molar ratio is optimal for enhancing milk fermentation and product shelf life.
- These nanoparticles present a sustainable and efficient solution for both chemical catalysis and food preservation.
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