The present study aimed to evaluate the polysaccharides extracted from Toona sinensis seeds using ultrasound-assisted deep eutectic solvent (DES). The extracted polysaccharides (TSRP) were purified and studied for their hypoglycemic and antioxidant activities. The purified polysaccharides (TSRPs-1) were hydrolyzed and derivatized to study their monosaccharide composition. The optimum extraction conditions were DES (choline chloride to oxalic acid) at a molar ratio of 1.473:1, ultrasound time of 50.643 min, and a material-to-liquid ratio of 1:31.838 g/mL. The ultrasound-assisted DES extraction was more effective (56.1%) as compared to the water extraction (35.89%). The inhibition of α-glucosidase by TSRPs-1 was 42.77% at a concentration of 0.8 mg/mL. At 3.2 mg/mL, TSRPs-1 inhibited α-amylase by 34.38%. The clearance of DPPH by TSRPs-1 was 24.36% at 3.2 mg/mL. The IC 50 for ABTS· + clearance by TSRPs-1 was 0.233 mg/mL. It was shown that the monosaccharides of TSRPs-1 were composed of Man, Rha, GlcA, GalA, Glc, Gal, Xyl, and Ara in a molar ratio of 1:563.13:41.81:51.20:21.81:2244.58:3.73:1130.48. In this paper, the process of extracting TSRP with ultrasound-assisted DES was investigated and optimized. TSRPs-1 possesses certain hypoglycemic and antioxidant activities. Therefore, this paper can provide an experimental basis for the establishment of an industrialized production process of polysaccharides and the study of their biological activities.
An edible composite film was developed and applied for ready-to-eat sea cucumber storage to improve the product quality. The PAC film base is first prepared by mixing 0.5 % glycerin (GL) with 4 % polyvinyl alcohol (PVA) and 1 % arginine-modified chitosan (Arg-CTS) in the same volume. After the addition of nano-ZnO (ZnO) and thymol (Thy) to the PAC film base, the mechanical properties and functions were tested. Compared to the PAC film, the PAC-ZnO-ThyH composite film showed a 1.34-fold increase in the DPPH scavenging rate and a 2.19-fold increase in the ABTS scavenging rate. Contrary to the PAC film, the inhibition zone diameter of Escherichia coli and Staphylococcus aureus significantly increased by 2.35 and 4.08 folds in the PAC-Zno-ThyH film, respectively. After applying the PAC-ZnO-ThyH film to store ready-to-eat sea cucumber for 10 days, there was a significant reduction in weight loss, total volatile basic nitrogen (TVB-N), and lipid oxidation levels to 1.47 and 1.26 folds to the Ctrl group. After preservation, the hardness and chewiness of ready-to-eat sea cucumber were maintained at 1079.62 ± 138.86 N and 913.73 ± 175.79 N, respectively. The novel PAC-ZnO-ThyH composite film can be used as an active food packaging for promising seafood applications.
危险品化学品经营许可证（带存储）