CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China.
School of Food Science and Technology, Southwest Minzu University, Chengdu 610225, China.
Int J Biol Macromol. 2024 Aug;275(Pt 1):134086. doi: 10.1016/j.ijbiomac.2024.134086. Epub 2024 Jul 31.
Iturin A (IA) encapsulated in chitosan (CS) microcapsules (IA/CS) underwent thorough physicochemical characterization using thermogravimetric analysis (TGA), Fourier-transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). SEM confirmed the smooth, spherical morphology of the IA/CS microcapsules, while FTIR revealed complex intermolecular interactions between IA and CS. TGA demonstrated thermal stability within the 0-100 °C range, while particle size analysis revealed an average diameter of 553.4 nm. To evaluate IA/CS efficacy in post-harvest grape preservation, grapes were treated with sterile water (CK), 10 g/L CS, 0.1 g/L IA/CS, and 0.1 g/L chitosan empty microcapsules (CKM), then stored at 25 °C for 16 days. IA/CS significantly reduced decay and respiration intensity by 52.3 % and 23.8 %, respectively, compared to CK. IA/CS treatment also inhibited abscission rate, weight loss, firmness reduction, total soluble solids consumption, titratable acidity consumption, polyphenol oxidase, and peroxidase activities on par with CS treatment (p > 0.05), but performed better than CK (reductions of 26.9 %, 41.2 %, 25.8 %, 27.2 %, 24.2 %, 19.4 %, and 17.4 %, respectively) and CKM (p < 0.05). Sensory evaluation confirmed that IA/CS effectively suppressed decay, slowed post-harvest metabolic activity, and maintained grape quality. Therefore, IA/CS microcapsules offer a promising method for extending grape shelf life and preserving quality.
将鱼精蛋白（IA）封装在壳聚糖（CS）微胶囊（IA/CS）中，通过热重分析（TGA）、傅里叶变换红外（FTIR）光谱和扫描电子显微镜（SEM）进行了全面的物理化学特性分析。SEM 证实了 IA/CS 微胶囊的光滑、球形形态，而 FTIR 则揭示了 IA 和 CS 之间复杂的分子间相互作用。TGA 表明在 0-100°C 范围内具有热稳定性，而粒度分析则显示平均直径为 553.4nm。为了评估 IA/CS 在采后葡萄保鲜中的功效，将无菌水（CK）、10g/L CS、0.1g/L IA/CS 和 0.1g/L 壳聚糖空微胶囊（CKM）处理过的葡萄进行处理，然后在 25°C 下贮藏 16 天。与 CK 相比，IA/CS 分别将腐烂率和呼吸强度降低了 52.3%和 23.8%。IA/CS 处理还抑制了脱落率、失重、硬度降低、总可溶性固形物消耗、可滴定酸度消耗、多酚氧化酶和过氧化物酶的活性，与 CS 处理相当（p>0.05），但比 CK（分别降低 26.9%、41.2%、25.8%、27.2%、24.2%、19.4%和 17.4%）和 CKM（p<0.05）更好。感官评价证实，IA/CS 有效抑制了腐烂，减缓了采后代谢活性，保持了葡萄的品质。因此，IA/CS 微胶囊为延长葡萄货架期和保持品质提供了一种有前途的方法。
