Sustainable Extraction and Chitosan Aerogel Boost the Antibacterial Power of Chinese Hickory Husk Triterpenoids
A recent study led by researchers at Zhejiang University has introduced a sustainable method to extract antibacterial triterpenoids from the husks of Carya cathayensis, commonly known as Chinese hickory. These husks, typically considered agricultural waste, are rich in bioactive compounds with potential health benefits. The research focuses on utilizing these compounds to develop plant-based antimicrobial products, thereby adding value to agricultural by-products.
The extraction process employed a surfactant-mediated, ultrasound-assisted technique optimized through response surface methodology. This method achieved a triterpenoid yield of 33.92 ± 0.52 mg per gram of dry husk. Following extraction, the triterpenoids were purified using AB-8 macroporous resin, resulting in a 4.3-fold increase in purity. To enhance the application potential of these hydrophobic compounds, the purified triterpenoids were embedded into mesoporous chitosan aerogel spheres. These aerogels, characterized by a specific surface area of 97.1 m²/g and an adsorption capacity of 123.5 ± 0.71 mg/g, improved the solubility and stability of the triterpenoids.
Antibacterial assays demonstrated that the combination of chitosan aerogels and triterpenoid extracts exhibited a synergistic effect, significantly inhibiting the growth of Escherichia coli and Staphylococcus aureus. Notably, Staphylococcus aureus showed higher sensitivity to the treatment, likely due to differences in cell wall structures. These findings suggest that the integration of chitosan aerogels with triterpenoid extracts not only enhances compound solubility but also amplifies antibacterial efficacy.
The study underscores the potential of transforming agricultural waste into valuable antimicrobial agents through eco-friendly extraction methods and innovative delivery systems. By scaling up aerogel production and exploring multifunctional loading strategies, this approach could pave the way for sustainable applications in food safety, healthcare, and materials science.
This research was published in the journal Food Innovation and Advances on March 12, 2025, and was funded by the Key Research and Development Program of Zhejiang Province (2023C02042).