Linear Dextrin as Potential Insulin Delivery System: Effect of Degree of Polymerization on the Physicochemical Properties of Linear Dextrin–Insulin Inclusion Complexes

In the current study, linear dextrin (LD) was prepared using waxy potato starch debranched with pullulanase, which has attracted immense interest in the food, pharmaceutical, and cosmetic industries as a versatile ingredient. Various LDs were separated on the basis of their differential solubility in aqueous/ethanol solutions of different volumetric ratios. Three LD products—LD Fabrications with 40% ethanol (F-40); LD Fabrications with 50% ethanol (F-50); and LD Fabrications with 60%, 70%, and 80% ethanol (F-M)—were obtained with an average degree of polymerization (DP) values of 31.44, 21.84, and 16.10, respectively. The results of Fourier transform infrared spectroscopy (FT-IR) analysis revealed that the reaction mainly involved hydrogen bonding and a hydrophobic interaction between LD and insulin in the process of inclusion complex formation. X-ray diffraction (XRD) results indicated that insulin was encapsulated in LD. The results of circular dichroism (CD) showed that the changes in the secondary structure of insulin were negligible during the release from the inclusion complexes. The order of encapsulation capacity is as follows: the complex composed of F-M and insulin (F-M-INS) > the complex composed of LD and insulin (LD-INS) > the complex composed of F-50 and insulin (F-50-INS) > and the complex composed of F-40 and insulin (F-40-INS). F-M-INS inclusion complexes showed a better effect on reducing the release of insulin in gastric juice and promoting the release of insulin in intestinal juice and blood plasma than LD-INS.

Antimicrobial activity of Punica grantum leaves

Natural phytochemicals isolated from medicinal plants acts as inhibitors for pathogenic microorganisms which causes contagious diseases to human beings. The present study was done to explore the antimicrobial activity of aqueous and aqueous-ethanol extract of Punica grantum leaves. The phytochemical analysis of both the extracts revealed the presence of total phenolics & flavonoids at varied concentration. The antimicrobial activity of the extracts was carried out by disc diffusion method. Both the aqueous and aqueous-ethanol extract showed the antimicrobial activity against S. aureus, Shi. dysentriae & Shi. flexineri. The antimicrobial activity of the Punica grantum leaves extracts could be attributed by the presence of phenolics and flavonoids.

Three-dimensional simulation analysis of the effect of hydrous ethanol and exhaust gas recirculation on gasoline direct injection engine combustion and emissions

To analyze the influence of hydrous ethanol on the performance of the direct injection engine, the three-dimensional simulation is carried out by using CONVERGE software coupled with the combustion mechanism of hydrous ethanol gasoline and the soot model. The combustion and soot generation characteristics of a direct injection gasoline engine burning aqueous ethanol gasoline using exhaust gas recirculation (EGR) technology were investigated. It was found that the increase of the blending ratio of the hydrous ethanol can accelerate the flame propagation speed, shorten the combustion duration, and improve the combustion isovolume. The nucleation and growth of soot are jointly controlled by PAHs and the small molecular components such as C2H2. The oxygen content properties and high reactive OH of the aqueous ethanol-containing gasoline inhibit soot formation. Compared with pure gasoline, the carbon soot precursor mass was reduced by 60%, 54.5%, 73.3% and 52.4% for 20% anhydrous ethanol blended with gasoline, A1, A2, A3 and A4, respectively, and the carbon soot mass was reduced by 63.6% and the carbon soot volume density was reduced by 40%. The introduction of EGR exhaust reduces the burning rate and leads to an increase in the production of Carbon monoxide, hydrocarbon, and soot. However, the combination of EGR with aqueous ethanol gasoline can significantly improve the engine combustion environment, significantly reducing soot and PAHs concentrations. The impact of EGR also includes the ability to reduce combustion chamber temperatures and reduce NOx emissions from aqueous ethanol gasoline by 75%.