<p>Fresh tomatoes have a short shelf life of 4–8 days due to dehydration, aging and microbial infection, resulting in serious decay and waste. In this study, an edible chitosan (CS)-based coating was prepared by incorporating nano zinc oxide (nano-ZnO) biosynthesized using <i>Cinnamomum camphora</i> (L.) leaf extract, known for their antimicrobial and antioxidant properties. Structural characterization revealed that hydrogen bonding formed between CS and nano-ZnO significantly enhanced the mechanical and barrier properties of the composite film, especially 40 mg·L<sup>− 1</sup> nano-ZnO (CTS-40). Compared with pure chitosan, CTS-40 exhibited a 1.61- and 14.46-fold increase in tensile strength and elongation at break, respectively. Meanwhile, water vapor transmittance, light transmittance, and water solubility decreased by 25.98%, 8.35%, and 29.47%, respectively. Furthermore, in vitro test showed the CTS-40 film inhibited the mycelial growth of <i>Alternaria alternata</i> by 99.02%. After 7 days of storage, CTS-40-coated tomatoes exhibited significantly reduced disease incidence and lesion diameter accompanied by increased the activities of antioxidant enzymes and accumulation of total phenols, flavonoids and anthocyanins. Overall, nano-ZnO/chitosan coating film can serve as a promising, efficient, environmentally friendly and easy to operate alternative to pesticides for the preservation of tomatoes and other fresh fruits.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Preparation of chitosan-based coating enriched with zinc oxide nanoparticles for inhibiting Alternaria alternata on tomato fruits

  • Mingsi Tong,
  • Wenjia Zhu,
  • Yanfang Ren,
  • Ke Li,
  • Boya Yang,
  • Runan Zhang,
  • Junyu He

摘要

Fresh tomatoes have a short shelf life of 4–8 days due to dehydration, aging and microbial infection, resulting in serious decay and waste. In this study, an edible chitosan (CS)-based coating was prepared by incorporating nano zinc oxide (nano-ZnO) biosynthesized using Cinnamomum camphora (L.) leaf extract, known for their antimicrobial and antioxidant properties. Structural characterization revealed that hydrogen bonding formed between CS and nano-ZnO significantly enhanced the mechanical and barrier properties of the composite film, especially 40 mg·L− 1 nano-ZnO (CTS-40). Compared with pure chitosan, CTS-40 exhibited a 1.61- and 14.46-fold increase in tensile strength and elongation at break, respectively. Meanwhile, water vapor transmittance, light transmittance, and water solubility decreased by 25.98%, 8.35%, and 29.47%, respectively. Furthermore, in vitro test showed the CTS-40 film inhibited the mycelial growth of Alternaria alternata by 99.02%. After 7 days of storage, CTS-40-coated tomatoes exhibited significantly reduced disease incidence and lesion diameter accompanied by increased the activities of antioxidant enzymes and accumulation of total phenols, flavonoids and anthocyanins. Overall, nano-ZnO/chitosan coating film can serve as a promising, efficient, environmentally friendly and easy to operate alternative to pesticides for the preservation of tomatoes and other fresh fruits.