Abstract
Baicalin, an active flavonoid ingredient of Scutellaria baicalensis Georgi, was extracted by heat reflux extraction and showed the same significance UV absorption property with standard baicalin. Active films were prepared from polyvinyl alcohol (PVA) containing baicalin extract by casting method. The effect of baicalin extracts on the UV-blocking, optical, antioxidant property, water vapor permeability, swelling and mechanical properties of the films were studied. UV–vis transmittance spectra showed that PVA films incorporated with baicalin extract blocked ultraviolet light range from 280–400 nm even with low concentration of baicalin (0.5 wt%) and maintain the high transparency in visible spectrum. The outstanding UV-blocking properties of PVA films incorporated with baicalin extract were also confirmed by Rhodamine B degradation. Baicalin conferred antioxidant properties to PVA films as determined by DPPH radical scavenging activity. Due to the interaction between hydroxy groups of baicalin and PVA molecule, water vapor permeability, swelling and elongation at break of the films were decreased accompanied with the increasing in tensile strength and Young’s modulus. FTIR reveal that the interaction between PVA molecules was significant changed by the introduction of baicalin. These results suggest that PVA film incorporated with baicalin extract can be used for the development of functional protective film.
Funding source: Education Department of Shaanxi Province
Award Identifier / Grant number: 19JK0362
Funding source: China National Textile and Apparel Council
Award Identifier / Grant number: 2019040
Funding source: Xi’an Polytechnic University
Award Identifier / Grant number: BS1721
Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: This work was supported by the Natural Science Foundation of Shaanxi Provincial Department of Education (grant no. 19JK0362), Science and Technology Guidance Project of China National Textile and Apparel Council (grant no. 2019040], and the PhD Research Funds of Xi’an Polytechnic University (grant no. BS1721).
Conflict of interest statement: The authors declare no potential conflicts of interest with respect to the research, authorship and/or publication of this article.
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