Antioxidant, Diabetic and Inflammatory Activities of Alpinia calcarata Roscoe Extract

Abstract

AbstractBackground: Alpinia calcarata (AC) Roscoe of Zingiberaceae popularly known as lesser galangal has a widespread occurrence in China, India, Sri‐Lanka, Bangladesh, Malaysia, Indonesia and Thailand. Essential oil (Eoil) was obtained from leaves/rhizomes of AC via hydro‐distillation process. Methods: To identify chemical ingredients in oil from leaves/rhizomes of AC through GC/MS technique for volatile components and their anti‐oxidant, inflammatory/diabetic activities. Results: The 38 and 65 components were found to make up 99.9 and 99.6 %, respectively in total of Eoil composition of AC leaves/rhizomes. Key chemical constituents were eucalyptol (28.7 % in leaves; 25.4 % in rhizomes), camphor (12.8 % in leaves; 4.2 % in rhizomes), and carotol (9.8 % in leaves; 5.6 % in rhizomes) found in oil of AC leaves/rhizomes. Colorimetric assay showed anti‐oxidant activities in leaves and rhizomes are IC50=71.01±0.71 μg/mL and IC50=73.83±0.49 μg/mL, respectively in the Eoils. Eoils had high anti‐oxidant capabilities in IC50‐values of AC‐L‐Eoil=43.09±0.82&AC‐Rh‐Eoil=68.11±0.87 in reducing power in μg/mL was found. Albumin test of rhizome oil had IC50‐values of 15.19±0.25 μg/mL. Concentrations range of 7.81 μg/mL and 250 μg/mL in the Eoils of AC leaves and rhizome, respectively by α‐glucosidase inhibition assay. Conclusion: Our findings demonstrated that leaf oil was slightly more promising results than rhizome oil of AC extract, which was ultimately showed medicinal potential of secondary metabolites with anti‐oxidant, diabetic/inflammatory activities. Further, Eoils of AC have a wide range of pharmacological potential and promising anti‐diabetic effects.