Oxidized β-cyclodextrins with different oxidation levels were prepared using hydrogen peroxide as the oxidant and copper sulfate as the catalyst. The physicochemical, antimicrobial and antifungal properties of oxidized β-cyclodextrin were systematically studied. The results showed that the oxidation level of oxidized β-cyclodextrin was successfully controlled by adjusting the dosage of hydrogen peroxide. The aqueous solubility of oxidized β-cyclodextrin was highly improved as expected. However, oxidation changed the morphology and partly reduced the crystallinity of oxidized β-cyclodextrin due to the introduced carbonyl and carboxyl groups. It is interesting that oxidized β-cyclodextrin presented a broad-spectrum antimicrobial activity, which was efficiently improved with the increasing oxidation level. Growth of A. niger spores was efficiently inhibited in the presence of oxidized β-cyclodextrin. Moreover, oxidized β-cyclodextrin could effectively extend the storage time of apple. In summary, oxidized β-cyclodextrin shows potential as antimicrobial and antifungal agents in food industry.

中文翻译：

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高水溶性和广谱抗菌活性的氧化β-环糊精的合成

以过氧化氢为氧化剂，硫酸铜为催化剂，制备了氧化程度不同的氧化β-环糊精。对氧化的β-环糊精的理化，抗微生物和抗真菌性能进行了系统的研究。结果表明，通过调节过氧化氢的用量可以成功地控制氧化的β-环糊精的氧化水平。氧化的β-环糊精的水溶性大大提高。然而，由于引入了羰基和羧基，氧化改变了形态并部分降低了氧化的β-环糊精的结晶度。有趣的是，氧化的β-环糊精具有广谱抗菌活性，随着氧化水平的提高，这种活性得到了有效改善。黑曲霉的生长在氧化的β-环糊精存在下，孢子被有效抑制。此外，氧化的β-环糊精可以有效地延长苹果的贮藏时间。总之，氧化的β-环糊精在食品工业中显示出作为抗菌剂和抗真菌剂的潜力。