Comparative Evaluation of Antioxidant and Enzyme Inhibitory (α-Amylase and α-Glucosidase) Activities of Piper betle L. Cultivars from a Single Origin
Somphon Khonphian, Natthaporn Manojai, Tanwat Prasopmoo, Chuthamat Duangkamol, Rapheepraew SodkhomkhumIntroduction:
Medicinal plants have many different types of chemical compounds. Therefore, these chemicals may be affected by various environmental factors when they are used for medicinal purposes in order to determine if there is a correlation between the type of Piper betle L. cultivars and their bioactive compounds.
Method:
In this study, four different cultivars (PB1-PB4) from the same location in Trang Province, Thailand, were investigated. The total phenolic and flavonoid contents of the ethanolic leaf extracts from each cultivar were compared. Furthermore, the free radical scavenging capacity, as well as the α-amylase and α-glucosidase inhibitory activities, were evaluated.
Results:
The PB2 extract exhibits total phenolic and flavonoid levels of (112.031 ± 5.976 mg GAE/g and 932.385 ± 20.093 mg QE/g, respectively. The free radical scavenging activity was found to be prominent against DPPH with an IC50 of 0.083 ± 0.003 mg/ml and against ABTS with an IC50 of 0.027 ± 0.002 mg/ml.
Discussion:
Cultivar PB2 exhibited the highest total phenolic and flavonoid contents, corresponding to the greatest free radical scavenging capacity among all tested cultivars. Furthermore, our in vitro studies demonstrated a highly favorable selective enzyme inhibitory profile for the bioactive compounds in PB1, characterized by potent α -glucosidase inhibition paired with minimal α - amylase activity.
Conclusion:
Overall, this single origin study provides evidence that the bioactivity of P. betle is primarily controlled by genetic variation and highlights cultivars PB1 and PB2 as potential candidates for developing natural therapeutic agents to manage oxidative stress and Type II diabetes.