Profiling and characterization antioxidant activities in Anoectochilus formosanus hayata

Area of Science:

• Phytochemistry
• Pharmacology
• Natural Product Chemistry

Background:

• Anoectochilus formosanus is recognized for its medicinal properties.
• Understanding its phytochemical profile and antioxidant capacity is crucial for therapeutic applications.
• Oxidative stress is implicated in various chronic diseases.

Purpose of the Study:

• To evaluate the phytochemical characteristics and antioxidant activities of Anoectochilus formosanus extracts.
• To investigate the impact of acid hydrolysis on the antioxidant potential of a butanol fraction.
• To identify novel compounds with antioxidant properties.

Main Methods:

• Extraction and fractionation of Anoectochilus formosanus.
• Acid hydrolysis treatment of the butanol fraction.
• Antioxidant assays including DPPH radical scavenging and superoxide anion scavenging.
• DNA protection assay against H(2)O(2)-induced cleavage.
• Metabolite profiling using chromatography and spectroscopy.
• Cellular antioxidant activity assessment in HL-60 cells.

Main Results:

• Acid hydrolysis of the butanol fraction (BuOH) yielded an acid-hydrolyzed BuOH fraction with significantly enhanced antioxidant activity.
• The IC(50) for DPPH radical scavenging decreased from 0.521 mg/mL (BuOH) to 0.021 mg/mL (acid-hydrolyzed BuOH).
• The acid-hydrolyzed BuOH fraction demonstrated superior superoxide anion scavenging activity compared to catechin and protected DNA from oxidative damage.
• Metabolite analysis confirmed the conversion of flavonoid glycosides to aglycones post-hydrolysis, correlating with increased antioxidant capacity.
• One new diarylpentanoid (kinsenone) and three known flavonoid glycosides were identified, exhibiting potent antioxidant properties.

Conclusions:

• Acid hydrolysis is an effective method to enhance the antioxidant properties of Anoectochilus formosanus extracts.
• The enhanced activity is attributed to the release of aglycones from flavonoid glycosides.
• The identified compounds, including kinsenone, possess significant antioxidant potential, warranting further investigation for pharmaceutical development.