Search

In this study, we have investigated a series of indole-based compounds for their inhibitory study against pancreatic α-amylase and intestinal α-glucosidase activity. Inhibitors of carbohydrate degrading enzymes appear to have an essential role as antidiabetic drugs. All analogous exhibited good to moderate α-amylase (IC 50  = 3.80 to 47.50 μM), and α-glucosidase inhibitory interactions (IC 50  = 3.10-52.20 μM) in comparison with standard acarbose (IC 50  = 12.28 μM and 11.29 μM). The analogues 4, 11, 12, 15, 14 and 17 had good activity potential both for enzymes inhibitory interactions. Structure activity relationships were deliberated to propose the influence of substituents on the inhibitory potential of analogues. Docking studies revealed the interaction of more potential analogues and enzyme active site. Further, we studied their kinetic study of most active compounds showed that compounds 15, 14, 12, 17 and 11 are competitive for α-amylase and non- competitive for α-glucosidase., (Copyright © 2021 Elsevier B.V. All rights reserved.)

In current study, α-amylase of fungal origin was immobilized using cross-linking strategy. The influence of precipitant (ammonium sulphate) and cross-linker (glutaraldehyde) concentration revealed that 60% (w/v) precipitant and 1.5% (v/v) cross-linker saturation was required to attain optimum activity. Cross-linked amylase aggregates (CLAAs) were characterized and 10-degree shift in optimum temperature (soluble enzyme: 50 °C; cross-linked: 60 °C) and 1-unit shift in pH (soluble enzyme: pH -6; cross-linked: pH -7) was observed after immobilization. The V max for soluble α-amylase and its cross-linked form was 1225 U ml -1 and 3629 U ml -1 , respectively. The CLAAs was more thermostable than its soluble form and retained its 30% activity even after 60 min of incubation at 70 °C. Moreover, cross-linked amylase retained its activity after two months while its soluble counterpart lost its complete activity after 10 and 20 days at 30 °C and 4 °C storage, respectively. Reusability test showed that cross-linked amylase could retain 13% of its residual activity after 10 repeated cycles. Therefore, 10 times more glucose was produced after cross-linking than soluble amylase when it was utilized multiple times. This study indicates that amylase aggregates are highly effective for continuous liquefaction of starch, hence have strong potential to be used for different industrial processes., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Piperazine Sulfonamide analogs (1-19) have been synthesized, characterized by different spectroscopic techniques and evaluated for α-amylase Inhibition. Analogs 1-19 exhibited a varying degree of α-amylase inhibitory activity with IC 50 values ranging in between 1.571 ± 0.05 to 3.98 ± 0.397 μM when compared with the standard acarbose (IC 50  = 1.353 ± 0.232 μM). Compound 1, 2, 3 and 7 showed significant inhibitory effects with IC 50 value 2.348 ± 0.444, 2.064 ± 0.04, 1.571 ± 0.05 and 2.118 ± 0.204 μM, respectively better than the rest of the series. Structure activity relationships were established. Molecular docking studies were performed to understand the binding interaction of the compounds., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Twenty five derivatives of indole carbohydrazide (1-25) had been synthesized. These compounds were characterized using 1 H NMR and EI-MS, and further evaluated for their α-amylase inhibitory potential. The analogs (1-25) showed varying degree of α-amylase inhibitory potential. ranging between 9.28 and 599.0µM when compared with standard acarbose having IC 50 value 8.78±0.16µM. Six analogs, 25 (IC 50 =9.28±0.153µM), 22 (IC 50 =9.79±0.43µM), 4 (IC 50 =11.08±0.357µM), 1 (IC 50 =12.65±0.169µM), 8 (IC 50 =21.37±0.07µM) and 14 (IC 50 =43.21±0.14µM) showed potent α-amylase inhibition as compared to the standard acarbose (IC 50 =8.78±0.16µM). All other analogs displayed good to moderate inhibitory potential. Structure-activity relationship was established through the interaction of the active compounds with enzyme active site with the help of docking studies., (Copyright © 2017 Elsevier Inc. All rights reserved.)