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In order to realize the ultraviolet (UV) protection property and antimicrobial activity simultaneously, as well as the natural dyeing process, oak bark extract was prepared and applied to dye tussah silk fabric. The effects of dyeing pH value, temperature, time and mordant kinds on dyeing properties of tussah silk fabric were analyzed. The results indicated that the optimum direct dyeing conditions were as follows: pH 5.0, temperature 98℃, time 80 min. As for the mordant dyeing process, the K/ S values of the post-mordant dyed samples were higher than those of the pre-mordant dyed samples. The color of the direct, aluminum potassium sulfate, copper sulfate and the ferrous sulfate dyed samples were brown, yellow-brown, dark brown and gray black, respectively. The washing, rubbing and light fastness of the three mordants dyed samples were all good. Moreover, the dyed samples showed an excellent UV protection property and antimicrobial activity. The UV protection factor values of the mordant dyed sample were more than 40; the reduction in bacterial count percent against S. aureus and E. coli reached up to and above 85% and 80%, respectively; and the weight gain rate was more than 6%. Furthermore, the dyed samples had good washing durability of the UV protection function and antimicrobial activity even after 50 consecutive launderings.

In order to reutilise the byproducts of foods and crops to benefit the environment and economise on resources, the natural extracts from chestnut shell and black rice bran were applied in the simultaneous dyeing and multifunctionalisation of silk fabrics. In this work, the influence of pH value on dyeing properties was studied. The effects of the ratio of chestnut shell and black rice bran extracts and the application of mordants (aluminium potassium sulphate and ferrous sulphate) on the dyeing performance as well as antiultraviolet and antioxidant properties of treated silk were also discussed. The results showed that deepcoloured silk fabrics can be obtained when dyed with the two natural extracts as the pH value of the dyebath approached 3. The ratio of the two natural extracts and the use of the mordants have significant effects on colour depth, colour hue, colour fastness, and the functionalities of dyed silk fabrics. Combination dyeing and mordanting are able to enrich the colour hues of dyed fabrics. The washing, rubbing, and light fastness of the dyed fabrics after mordanting can be rated higher than grade 4. Moreover, the silk after combination dyeing has good UV protection performance (UPF > 30) and antioxidant activity. In addition, the functionalities of treated fabrics showed excellent washing fastness. This study reveals that chestnut shell and black rice bran extracts are suitable as natural colourants and multifunctional finishing agents for the preparation of coloured and multifunctional silk materials.

Objective To evaluate the hypoglycemic effect of Picris japonica Thunb (Asteraceae) on KK-Ay mice. Methods The hypoglycemic effect of Picris japonica aqueous extract (PJE) in a spontaneous type 2 diabetic model (KK-Ay mice) was studied in the present research. PJE was administrated at doses of 700 mg/kg and 350 mg/kg (calculated as crude herb) for 14 days and blood glucose, oral glucose tolerance test, plasma insulin level, and blood lipid were evaluated. Meanwhile, Rosiglitazone was used for the positive control. Results It was found the PJE treatment significantly reduced blood glucose level and improved oral glucose tolerance ability (p < 0.01 or p < 0.05) in a dose-dependent manner compared to the control diabetic mice. The blood insulin levels were significantly reduced in PJE-treated mice (700 mg/kg) and Rosiglitazone compared with the diabetic control (p < 0.01). Compared with the control diabetic group, the serum total cholesterol, triglyceride, and low density lipoprotein cholesterol were reduced by PJE (700 mg/kg) and Rosiglitazone (p < 0.05), and the serum high density lipoprotein cholesterol was significantly increased only by Rosiglitazone (p < 0.01). Conclusions The findings demonstrate that Picris japonica has remarkable antidiabetic effect in diabetic KK-Ay mice, which suggests that Picris japonica may be beneficial to the treatment of type 2 diabetes mellitus.