In vitro α-amylase inhibitory effect of TLC isolates of Aloe megalacantha baker and Aloe monticola Reynolds

Abstract

About 425 million adults had diabetes mellitus globally in 2017. Type 2 diabetes accounts for the enormous majority of diabetes cases and it is gradually growing which is predicted to increase by 48% in 2045. Imbalanced cellular carbohydrate and lipid metabolism cause an increase in postprandial blood glucose level which eventually leads to the onset and progression of type 2 diabetes mellitus. The lack of effective and safe carbohydrate hydrolyzing enzyme inhibitors contributes to the increasing prevalence. Thus, this study was targeted to assess the α-amylase inhibitory potential of isolates obtained from Aloe megalacantha Baker and Aloe monticola Reynolds, which are among the commonly used folkloric remedies for the management of diabetes mellitus. The α-amylase inhibitory effect of Aloe megalacantha Baker and Aloe monticola Reynolds were evaluated using the 3,5-dinitro salicylic acid method. 2, 2-Diphenyl-2-picrylhydrazyl free radical scavenging property was also used to test the antioxidant effect of both plants. Results were analysed using GraphPad Prism software version 8. The more polar isolates (AM 1 and AG 1 ) were possessed stronger α-amylase inhibition activity than the leaves latex and the other strains (AM 2 and AG 2 ). Leaf latex of A. megalacantha , AM 1 , AM 2 , leaf latex of A. monticola , AG 1 , and AG 2 were found to have an IC 50 value of 74.76 ± 1.98, 37.83 ± 3.31, 96.75 ± 1.98, 78.10 ± 1.88, 56.95 ± 1.88 and 64.03 ± 3.60 μg/mL, respectively ( P < 0.001 ). The leaf latexes of A. megalacantha and A. monticola showed a significant ( P < 0.001 ) free radical hunting property with an IC 50 value of 890.1 ± 1.73 and 597.5 ± 2.02 μg/mL, respectively. Hence, the outcomes of the present investigation partly justify the acclaimed use of Aloe megalacantha and Aloe monticola for the treatment of diabetes.