Page 77 - journal-6-2-S-Full

˜ˆ «“√ “√°“√·æ∑¬å·ºπ‰∑¬·≈–°“√·æ∑¬å∑“߇≈◊Õ° ªï∑’Ë ˆ©∫—∫∑’Ë Ú æƒ…¿“§¡- ‘ßÀ“§¡ (©∫—∫‡ √‘¡) ÚııÒ

OR-36

Phenolic contents and antioxidant activity of Acanthopanax trifoliatus

Pongtip Sithisarn, Siripen Jarikasem, Sarinthip Muensaen, Juree Tungrithaiwanich,
Taweesak Suntorntanasat

Pharmaceutical and Natural Products Department, Thailand Institute of Scientific and Technological Research, Technopolis,
35 M.3, Klong 5, Klong Luang, Pathumthani 12120, Thailand.

Rationale: Acanthopanax trifoliatus (L.) Voss is a plant in Araliaceae family that has been traditionally used for
ginseng-like purposes. Since oxidative stress is believed to cause many diseases including age-related disorders.
Total phenolic and total flavonoid contents and antioxidant activity of extracts from various parts of A. trifoliatus
were investigated to confirm ethnomedical uses.

Objective: To investigate total phenolic and total flavonoid contents by spectroscopic techniques and to investi-
gate antioxidant activity using 1,1-diphenyl-2-picryl-hydrazyl (DPPH) scavenging assay and thiobarbituric acid
reactive substances (TBARS) method.

Methodology: The leaves, stems, stem barks, roots and root barks of A. trifoliatus were collected from Chiang
Mai province in April 2007. Plant samples were extracts by decoction and investigated for total flavonoid and total
phenolic contents using aluminum chloride and Folin-Ciocalteu reagents, respectively. All extracts were also tested

for free radical scavenging activity using DPPH assay and inhibitory effect to lipid peroxidation of rat brain
homogenate by TBARS method.

Results: Young leaf and root bark extracts showed strong DPPH scavenging activity with EC50 of 14.50 ± 1.04
and 34.24 ± 5.01 µg/ml, respectively while the root, young and mature leaf extracts exhibited high efficiency to
inhibit lipid peroxidation of rat brain homogenate tested by TBARS method with EC of 11.18 ± 2.6, 16.11 ± 0.29
50
and 18.99 ± 2.51 µg/ml, respectively. Total phenolic and total flavonoid contents of the extracts ranged from 9.97
to 19.78 g% chlorogenic acid equivalent (g% CAE) and 0.42 to 1.49 g% rutin equivalent (g% RE), respectively.

Conclusion: Extracts from various parts of A. trifoliatus showed free radical scavenging activity tested by DPPH
scavenging assay and inhibitory effect to lipid peroxidation of rat brain homogenate tested by TBARS method. The
root bark and young leaf extracts exhibited strong antioxidant activity determined by both methods and contained

the highest total phenolic and total flavonoid contents about 19.78 ± 0.44 g% CAE and 1.49 ± 0.03 g% RE and
16.26 g% CAE and 1.31 ± 0.01 g% RE, respectively. It was found that extracts with higher amount of phenolic
and flavonoid compounds showed stronger antioxidant activities. However, phenolic and flavonoid contents have
more correlation to DPPH scavenging activity than inhibitory effect to lipid peroxidation of rat brain homogenate

tested by TBARS method.