ANTI-NUTRITIONAL CONSTITUENT OF COLOCASIA ESCULENTA ...

C.1.3
Cl.3.!
replaces some of the cholesterol in the cell membrane, which ultimately triggers the
relaying ofan instruction to the cells not to divide (Awad et al., 2000).
Thus, dietary plant sterols also have possible anti-cancer effects. Beta-sitosterol may
offer protection against breast cancer by stimulating apoptosis and by inhibiting tumor
growth in cancer tissue (Awad and Fink, 2000). Epidemiological studies have shown
positive association between higher dietary phytosterol intake and populations at lower
risk for colonic cancer (Hirai et al., 1986). Experimental studies by Raicht et al., (1980)
have shown that rats fed a diet containing 0.3 percent beta-sitosterol had a significantly
lower incidence of tumours when given methylnitrosourea (MNU), a chemical
carcinogen, than those on diets without beta-sitosterol supplement.
The toxic potential of a test article may be considerably affected by several factors such as
administration route, dosing form and the experimental conditions (Dain and Jaffe, 1988;
Dethloffet aI., 1996; Kim et aI., 2001). With regard to toxicity, no obvious side effects of
phytosterols have been observed in studies to date, except in individual with
phytosterolemia, an inherited lipid disorder (Ling and Jones, 1995). Beta-sitosterol has
been fed to rats in dosages ofbetween 0.5 and 5 mg kg- 1 (Young et al., 2004; Malini and
Vanithakumari, 1990, 1992). Kim et al (2002) investigated subchronic toxicity of plant
sterol ester by administering 1000, 3000 and 9000 mg kg- 1 day-l to rats . Based on their
results, 9000 mg kg- l day-l was considered to be the toxic dose since it resulted in the
suppression ofbody weight gain in both sexes and male cardiomyopathy.
Digestive enzymes
Disaccharidases
The nutritional building blocks derived from digestion are used by metabolic enzymes in
every cell, tissue and organ of the body to restore damage and decay, to combat and
overcome disease, to repair wounds and to maintain overall health and well-being.
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