RESUMO
Nowadays, substituting petroleum-based plastics with biodegradable polymers made from polysaccharides loaded with various reinforcing materials has recently gained attention due to the impact of conventional plastics wastes. In this study, polysaccharidic mucilage from Ethiopian cactus (Opuntia Ficus Indica) was derived using microwave-assisted extraction technique to develop biodegradable polymers that were inexpensive, readily available, simple to make, and ecofriendly. The effect of microwave power 300-800 W, solid-liquid (cactus-sodium hydroxide solution) ratio 1:5-1:25, sodium hydroxide concentration 0.1-0.8 mol/L, and extraction time 2-10 min on mucilage extraction were studied and the maximum yield of mucilage was attained at optimized parameters of 506 W, 1:20, 0.606 mol/L, and 9.5 min, respectively. Biodegradable polymers made with mucilage alone have poor mechanical characteristics and are thermally unstable. Thus, to overcome the stated problems, glycerol as a plasticizer and acid-leached kaolin crosslinked with urea as a reinforcing material were used. Moreover, the effect of acid-leached kaolin and glycerol on the physico-chemical properties of the films was studied, and a maximum tensile strength of 6.74 MPa with 18.45 % elongation at break, thermally improved biodegradability of 26 %, were attained at 10 % acid-leached kaolin and 20 % glycerol crosslinking with 2 % urea. But the maximum degradability of 53.5 % was attained at 30 % glycerol content. The control and reinforced biodegradable films were characterized using TGA, FTIR, SEM, and XRD to determine the thermal, functional group, morphology, and crystallinity of the bioplastics, respectively. These biodegradable plastics may be used for packaging application.
RESUMO
Background: Justicia schimperiana has been used traditionally for the treatment of different diseases, including, diabetes. Yet, no in vivo study was conducted to substantiate these claims. This study aimed to evaluate the effect of Justicia schimperiana roots extract on blood glucose levels and lipid profiles in streptozotocin-induced diabetic mice. Methods: Male Swiss albino mice weighing 25-35 g were induced diabetes with 150 mg/kg of STZ. Animals were randomly grouped into six groups of five each. Group I was a normal control, Group II was a Diabetic control, Group III-V were Diabetic Mice treated with the extract (100, 200, and 400 mg/kg) respectively, and Group VI was standard control. The treatments were followed for 14 days. The FBG measurements were done on 0, 7th, and 14th days of treatment. On the 15th day, the mice were anesthetized with diethyl ether; blood samples were collected for the assessment of serum lipid profiles. The antioxidant and α-amylase inhibitory activities of the extract were also investigated in vitro using the DPPH and DNSA assay methods, respectively. The data were entered into EPI DATA version 4.6, exported to IBM, SPSS version 26.0, and analyzed using a one-way ANOVA followed by Tukey's post hoc test. P < 0.05 was considered statistically significant. Results: The hydromethanolic extract of J. schimperiana roots exhibited no toxicity up to a dose of 2000 mg/kg body weight. In the STZ-induced diabetic mice, the extract reduced blood glucose levels at all tested doses: 100, 200, and 400 mg/kg on the 14th day as compared to diabetic control. The higher dose showed maximum reduction (29.73 %, p < 0.001) on the 14th day of treatment compared to the baseline. There were significant reductions in serum TG, TC, LDL, and a significant increase in body weight and HDL compared to the diabetic control. Besides, good antioxidant and α-amylase inhibitory activity were obtained from the in vitro laboratory tests. Conclusions: Evidence from our study revealed that the root extract of J. schimperiana has antihyperglycemic and antihyperlipidemic effects in STZ-induced diabetic mice.
