Planta Med 2010; 76 - P136
DOI: 10.1055/s-0030-1264434

Correlation of cytotoxicity, antioxidant activities, gamma-Oryzanol content and extraction methods of Hommali 105 rice bran (Oryza sativa)

S Uttama 1, I Sakpakdeejaroen 2, A Itharat 2
  • 1Student in Doctor of Philosophy Program, Faculty of Medicine, Thammasart University, Faculty of Medicine, Thammasart University, Klong Luang, 12120 Pathumtani, Thailand
  • 2Division of Applied Thai Traditional Medicine, Faculty of Medicine, Thammasart University, Division of Applied Thai Traditional Medicine, Faculty of Medicine, Klong luang, 12120 Pathumtani, Thailand

The objectives of this research are the investigation for the correlations of cytotoxicity against cancer cells, antioxidant activity, gamma oryzanol and extraction methods of Homali 105 rice bran (Oryza sativa) extracts. Sulphorhodamine (SRB) assay [1] was used to test cytotoxic activity against four human cancer cell lines: lung (CORL23), cervical (Hela), prostate (PC3) and breast (MCF-7) cancer cell lines and one normal human cell line (MRC5)[1,2]. DPPH assay [3] was carried out for antioxidant activity and gamma oryzenol content was determined by HPLC [4]. The methods of extraction were maceration by ethanol 95% (ME) supercritical fluid extraction (SFE), boiling in water and dry by freeze dry (BF), expression method (EX) and soxhlet extraction method by using different solvent as hexane, chloroform and methanol (SXH, SXC and SXM respectively). The results found that BF showed the highest percentage of yield (21.73%). SXC showed the highest percentage of selective cytotoxicity against only human cancer cells dependent on hormone at a concentration of 100µg/ml such as PC3, followed by Hela and MCF-7 (46.9, 29.6 and 21.58 respectively) but it had no cytotoxic activity against both COR-L23 and MRC5. ME method gave the highest gamma oryzenol content followed by EX and SXH (31.64, 27.90 and 25.88mg/g of extracts, respectively). There were no correlations between gamma oryzanol content and cytotoxicity, antioxidant activities and the methods of extraction. However, these results are very useful for the selection of the extraction method of rice bran hommali 105 extracts for treatment of cancer patients especially with types of cancer dependent on hormones.

Keywords: Hommali 105 rice bran, Oryza sativa, the extraction, cytotoxicity, SRB, Gamma Oryzanol, HPLC.

Acknowledgements: Faculty of medicine, Thammasart University and National Research Council of Thailand for financial support

References: 1. Itharat, A. et al. (2004)J. of Ethnopharmacology: 90:33–38.

2. Skehan P et al.(1990)J Natl Cancer Inst 1990: 82(13): 1107–12.

3. Yamazaki K, et al (1994) Chem Pharm Bull 1994; 42:1663–5.

4. Chotimakorn, C et al. (2008). Food Chemistry, 111, 636–641.