School of Chemical Engineering, Sichuan University, Chengdu 610065, China.
College of Chemistry and Environment Protection Engineering, Southwest University for Nationalities, Chengdu 610041, China.
Carbohydr Polym. 2017 Oct 15;174:1051-1058. doi: 10.1016/j.carbpol.2017.07.029. Epub 2017 Jul 13.
The oxidized κ-carrageenans with different oxidation levels were prepared through the hydrogen peroxide and copper sulfate redox system. The oxidation level of oxidized κ-carrageenan was successfully controlled by adjusting the dosage of hydrogen peroxide. The results showed that the microtopography of oxidized κ-carrageenan changed from rough granules to smooth flakes, mainly resulting from the easily melting property of oxidized κ-carrageenan induced by introduced carboxyl and aldehyde groups. Especially, the antibacterial activity of oxidized κ-carrageenans against Gram-positive bacteria (Staphylococcus aureus and Listeria monocytogenes) and Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) was systematically investigated. The results showed that the oxidized κ-carrageenan could damage the bacterial cell wall and cytoplasmic membrane and suppress the growth of both Gram-positive and Gram-negative bacteria. The oxidized κ-carrageenan possessed broad-spectrum antibacterial activity, which may be used as a new antibacterial agent.
通过过氧化氢和硫酸铜氧化还原体系制备了不同氧化水平的氧化κ-卡拉胶。通过调整过氧化氢的用量，成功地控制了氧化κ-卡拉胶的氧化水平。结果表明，氧化κ-卡拉胶的微观形貌从粗糙颗粒变为光滑薄片，主要是由于引入的羧基和醛基使氧化κ-卡拉胶的易熔性增强所致。特别是，系统研究了氧化κ-卡拉胶对革兰氏阳性菌（金黄色葡萄球菌和单核细胞增生李斯特菌）和革兰氏阴性菌（大肠杆菌和铜绿假单胞菌）的抗菌活性。结果表明，氧化κ-卡拉胶可以破坏细菌的细胞壁和细胞质膜，并抑制革兰氏阳性菌和革兰氏阴性菌的生长。氧化κ-卡拉胶具有广谱抗菌活性，可作为一种新型抗菌剂。
