1. Basic Properties
Product Name: Natamycin  
CAS Number: 7681-93-8  
Molecular Formula: C33H47NO13  
Molecular Weight: 665.73  
EINECS Number: 231-683-5  
Category: Polyene Macrolide  
2. Physical Properties
·Appearance: Natamycin is a near-white or cream-yellow crystalline powder, odorless and tasteless.  
·Solubility: It is practically insoluble in water, slightly soluble in methanol, and soluble in glacial acetic acid and dimethyl sulfoxide (DMSO). Its solubility increases at pH values higher than 9 or lower than 3.  
·Stability: Natamycin is relatively stable in dry form and can withstand short-term high temperatures (up to 100°C). However, due to its cyclic chemical structure, it is sensitive to ultraviolet light and should not be exposed to sunlight. Additionally, natamycin is highly sensitive to oxidizing agents.
3. Chemical Properties  
·Natamycin has a polyene planar macrolide structure. The conjugated double bonds interact through van der Waals forces with ergosterol or other sterol groups in fungi, forming a natamycin-ergosterol complex. This interaction causes distortion in the fungal cell membrane, altering its permeability and leading to leakage of essential intracellular substances, such as amino acids, ultimately resulting in cell death.
4. Performance Characteristics
·Broad-Spectrum Antifungal Activity: Natamycin has antifungal activity against nearly all yeast and mold species, effectively inhibiting the growth of various molds and yeasts and preventing the production of mycotoxins.  
·Low Toxicity: Natamycin is harmless to humans and is poorly absorbed by the digestive tract, making it highly safe for use.  
·Low Resistance Development: Microorganisms rarely develop resistance to natamycin, maintaining its antimicrobial effectiveness even with prolonged use.
5. Applications
·Food Preservation: Natamycin is used as a preservative in the food industry to extend shelf life. It can prevent mold and spoilage in products such as cheese, sausages, mooncakes, and baked goods, without affecting the taste or flavor of the food.  
·Pharmaceutical Treatment: Natamycin is used in the medical field to treat and prevent various fungal infections, such as skin fungal infections (e.g., athlete’s foot, ringworm), ocular fungal infections (e.g., corneal fungal infections), as well as fungal infections in livestock and pets.  
·Other Applications: Natamycin is also used in animal feed and cosmetics as a preservative and antimicrobial agent.
Natamycin is a widely used natural antifungal compound, and its unique chemical structure and performance characteristics make it an important agent in food preservation, medical treatments, and other industries.