Sains Malaysiana 39(5)(2010): 747–752

Kesan Pengekstrakan Terhadap Kandungan Polifenol, Aktiviti Antipengoksida dan pH Ekstrak Pegaga (Centella asiatica)

 (Effect of Extraction on Polyphenol Content, Antioxidant Activity and pH in Pegaga (Centella asiatica) Extract)

Ong Hooi Yung, Mohamad Yusof Maskat* & Wan Aida Wan Mustapha

Program Sains Makanan, Pusat Pengajian Sains Kimia dan Teknologi Makanan

Fakulti Sains dan Teknologi, Universiti Kebangsaan Malaysia

43600 Bangi, Selangor D.E., Malaysia

Received: 29 July 2008 / Accepted: 23 March 2010

ABSTRAK

Kajian ini telah dijalankan untuk menentukan kesan suhu (50, 70 dan 90 ^oC) dan masa didihan (15, 30 dan 90 minit) semasa pengekstrakan pegaga serta membandingkan kesan pengekstrakan dengan kaedah haba dan tanpa haba. Parameter yang diukur adalah kandungan polifenol jumlah, aktiviti antipengoksida dan pH. Hasil menunjukkan bahawa dengan peningkatan suhu dan masa pendidihan, kandungan jumlah polifenol dan aktiviti antipengoksida meningkat secara ketara melainkan pada suhu pengekstrakan 90 ^oC untuk aktiviti antipengoksida. Kandungan jumlah polifenol dan aktiviti antipengoksida dalam sampel pegaga yang terhasil tanpa haba adalah lebih rendah berbanding sampel yang terhasil dengan melibatkan haba. pH ekstrak pegaga meningkat dengan peningkatan suhu pengekstrakan. Sebaliknya, pH ekstrak pegaga semakin menurun dengan peningkatan masa pengekstrakan.

Kata kunci: Kesan suhu; masa didihan; pegaga; pengekstrakan; tanpa haba

ABSTRACT

This study was carried out to determine the effect of temperature (50, 70 and 90 ^oC) and heating time (15, 30 and 90 minutes) during the extraction of pegaga and also to compare the effect of extraction using heat and non-heat methods. Parameters measured were total polyphenol content, antioxidant activity and pH. Results showed that with an increase in boiling temperature and time, total polyphenol content and antioxidant activity increased significantly except for extraction temperature of 90 ^oC for antioxidant activity. The total polyphenol content and antioxidant activity from samples prepared without heat treatment were significantly lower than extracts prepared using heat treatment. The pH of pegaga extract increased with increase in extraction temperature. However, pH of pegaga extract decreased with the increase in extraction time.

Keywords: Effect of temperature; extraction; heating time; non-heat; pegaga;

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*Corresponding author; email: maskatmy@yahoo.com