Nadri Muhammad Helmi, Salim Yushatika, Basar Norazah, Yahya Azli, Zulkifli Razauden Mohamed
Department of Bioscience and Health Sciences, Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia (UTM), 81310 Skudai, Johor, Malaysia.
Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia (UTM), 81310 Skudai, Johor, Malaysia.
Afr J Tradit Complement Altern Med. 2014 Apr 3;11(3):107-11. doi: 10.4314/ajtcam.v11i3.16. eCollection 2014.
The ethyl acetate and chloroform extracts of stems, leaves and fruits of Phaleria macrocarpa were screened for their antioxidant capacity and tyrosinase inhibition properties.
The total phenolic content (TPC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and ferric-ion reducing power (FRAP) were used to evaluate their antioxidant capacity. Tyrosinase inhibition effect was measured using mushroom tyrosinase inhibition assay.
Ethyl acetate extract of P. macrocarpa's stem exhibited highest total phenolic content, DPPH free radical scavenging and ferric reducing power. Meanwhile, chloroform extracts of leaves and fruits demonstrated potent anti-tyrosinase activities as compared to a well-known tyrosinase inhibitor, kojic acid.
Since chloroform extracts of leaves and fruits have low antioxidant capacities, the tyrosinase inhibition effect observed are antioxidant independent. This study suggests direct tyrosinase inhibition by chloroform extracts of Phaleria macrocarpa.
对大果木竹子茎、叶和果实的乙酸乙酯和氯仿提取物进行了抗氧化能力和酪氨酸酶抑制特性筛选。
采用总酚含量（TPC）、1,1-二苯基-2-苦基肼（DPPH）自由基清除能力和铁离子还原能力（FRAP）来评估其抗氧化能力。使用蘑菇酪氨酸酶抑制试验测定酪氨酸酶抑制效果。
大果木竹子茎的乙酸乙酯提取物表现出最高的总酚含量、DPPH自由基清除能力和铁还原能力。同时，与著名的酪氨酸酶抑制剂曲酸相比，叶和果实的氯仿提取物表现出较强的抗酪氨酸酶活性。
由于叶和果实的氯仿提取物抗氧化能力较低，观察到的酪氨酸酶抑制作用与抗氧化作用无关。本研究表明大果木竹子氯仿提取物可直接抑制酪氨酸酶。
