Safaei Maryam, Roosta Azad Reza
Department of Chemical and Petroleum Engineering, Sharif University of Technology, Azadi Ave., Tehran, P.O. Box 11155-9465, Iran.
J Food Sci Technol. 2020 Apr;57(4):1242-1250. doi: 10.1007/s13197-019-04156-z. Epub 2019 Nov 15.
In this study, active poly lactic acid (PLA) films containing 0, 10, 20 and 40% w/w propolis extract (PE), as active agent, were developed. A high amount of phenolic content (PC) was measured in PE. The antioxidant effect of active PLA films was determined by measuring the PC of sausage slices after 0, 2 and 4 days storage at refrigerator. Results showed that phenolic compounds of PE were released from PLA films in quantities proportional to PE concentration. Disc diffusion test indicated that PE showed an inhibitory effect against and bacterial species but was more effective against gram-positive species. PE containing PLA films had antimicrobial effect on while in the case of , PLA/PE films needed polyethylene glycol (PEG)/CaCO content to show inhibitory effect. Addition of PE changed the tensile strength, elongation at break and elastic modulus of PLA films negatively. However, addition of PEG/CaCO improved the film mechanical properties and antimicrobial effect of films.
在本研究中，制备了含有0%、10%、20%和40%（w/w）蜂胶提取物（PE）作为活性剂的活性聚乳酸（PLA）薄膜。在PE中测得大量的酚类物质（PC）。通过测量香肠片在冰箱中储存0天、2天和4天后的PC来确定活性PLA薄膜的抗氧化效果。结果表明，PE中的酚类化合物从PLA薄膜中释放的量与PE浓度成正比。纸片扩散试验表明，PE对 和 细菌种类有抑制作用，但对革兰氏阳性菌更有效。含PE的PLA薄膜对 有抗菌作用，而对于 ，PLA/PE薄膜需要聚乙二醇（PEG）/碳酸钙含量才能显示出抑制作用。PE的添加对PLA薄膜的拉伸强度、断裂伸长率和弹性模量有负面影响。然而，PEG/碳酸钙的添加改善了薄膜的机械性能和抗菌效果。
