Malays. Appl. Biol. (1998) 27(1 & 2): 63-67
OPTIMIZATION OF CYTOTOXICITY ASSAY FOR ESTIMATING CD50 VALUES OF PLANT EXTRACTS AND ORGANOMETALLIC COMPOUNDS
A.M. MARINI1, I.E. AHMAD1*, M.D. YAHYA1 and B. M. YAMIN2
1 Department of Microbiology, Faculty of Life Sciences 2 Department of Chemistry, Faculty of Physical and Applied Sciences, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia
ABSTRACT
A study was conducted to optimize the parameters of an in vitro cytotoxicity assay based on absorbance values of solubilized sosin as the indicator of adherent cells. Cells used in this study were HeLa, HEp-2, RD, MRC-5, BHK-21, MDBK, BGM and Vero cells. The cells were treated with methanolic extracts of Cymbopogon nardus (L.) Rendle, Ancistrocladm tectorius Merr., Phaenthus crassipetalu and "jadam"; emetine hydrochloride and sodium chloride were used as controls. Fhe optimum parameters for the assay were: 2.5x105 cells/ml initial cell concentration, 2 days incubation with the tesl substance, 2 hours drying at 40°C, 2% eosin treatment of adherent cells, addition of 5 mM NaOH solution for redissolving 5osin, and absorbance measurement at 540 nm. Similar patterns of response to various test compounds were observed, with ;metine hydrochloride being the most toxic (CD50 < 0.27 ug/ml) and commercially available antiviral compounds being the least toxic (CD50 > 208 ug/ml). However, some variation in CD50 values were observed between different cell lines when tested with similar compounds.
ABSTRAK
Satu kajian telah dijalankan untuk mengoptimumkan parameter asai sitotoksisiti in vitro berdasarkan nilai serapan eosin :erlarut sebagai petunjuk kepada bilangan sel melekat. Warisan sel yang digunakan adalah HeLa, HEp-2, RD, MRC-5, BHK-21, MDBK, BGM dan Vero cells. Sel-sel tersebut diperlakukan dengan ekstrak Cymbopogon nardus (L.) Rendle, Ancistrocladus tectorius Merr., Phaenthus crassipetalus dan "jadam"; emetina hidroklorida dan natrium klorida digunakan >ebagai kawalan. Parameter-parameter optimum yang digunakan adalah: 2.5x105 sel/ml bagi kepekatan permulaan sel, 2 nan pengeraman dengan bahan ujian, 2 jam pengeringan pada 40°C, perlakuan 2% eosin terhadap sel-sel melekat, penambahan arutan 5 mM NaOH untuk melarutkan semula eosin, dan pengukuran serapan pada 540 nm. Ragam respon yang sama :erhadap sebatian-sebatian ujian dicerap dengan emetina hidroklorida sebagai yang paling toksik (CD50 < 0.27 ug/ml) dan sebatian-sebatian antivirus komersial sebagai yang paling rendah ketoksikan (CD50 > 208 ug/ml). Bagaimanapun, beberapa Derbezaan dalam nilai CD50 telah dicerap apabila sel-sel yang berlainan diperlakukan dengan bahan yang sama.
Key words: Cytotoxicity, organometallic compounds, plant extract
REFERRENCES
Adams, R.L.P. 1980. Cell Culture for Biochemists. Elsevier North-Holland Biomedical Press NewYork. pp: 20.
Ahmad, I.E. and Marini, A.M. 1993. The application of in vitro cytotoxicity assay foi determination of the LC5() value of sweet lemon grass extract. Proceedings Malaysian Microbiology Symposium, 28-19th October. 1993. pp: 114-115.
Ahmad, I.E. and Marini, A.M. 1994. Optical absorbance method for assay of cytotoxicity and antiviral activity of plant extracts. Proceeding JO"' Annual Seminar and UNESCO Regional Workshop on the Bioassay Guided Isolation of Natural Products, 18-23lxi October, 1993. pp: 13-21.
Anderson, M.M., O'Neil, M.J., Phillipson, J.O. and Warhurst, D.C. 1991 In vitro cytotoxicity of a series of quassinoids from Brucea javanica fruits against KB cells. Planta Medica, 57: 62-64.
Dombrowski, K.E., Baldwin, W. and Shearts, I.E. 1986. Metallocenes in biochemistry, microbiology and medicine. J. Organometallic Chemistry, 302: 281-306.
Kopf, H. and Kopf-Maeir, P. 1983. Tumor inhibition by metallocene dihalides of early transition metals. Chemical and biological aspects. ACS Symposium Series, 209: 315-333.
Nurmawati. 1981. Kajian Aktiviti Biologi Pokok Serai Wangi (Cymbopogon nardus (L.) Rendel). Tesis Sarjana, Jabatan Mikrobiologi, Fakulti Sains Hayat, UKM, Bangi. (Malay).
Schwobel, W., Streissel, G. and Kiefer, G. 1979. Attempts to standardize the screening for antiviral drugs by in vitro test. Chemotherapy, 25: 268-278.
Yamin, B.M., Hashim, N., Mohammed, R., Arof, K. and Zain, N.M. 1997. Structures and some properties of ferrocenium-antimonyl trichloride salts. Chimla, 517: 398.
