Spices May Prevent Human Cancers

Abstract

Industrial and domestic use of fossil fuel (coal, gasoline, natural gas), wood burning (for heating, cooking, forest wild fire), and tobacco smoking releases harmful chemicals to human environment. Air pollutants include a mixture of noxious gases such as carbon monoxide, carbon dioxide, nitrous oxide, polycyclic aromatic hydrocarbons (PAHs). PAHs are cancer causing agents are highly toxic and mutagenic/genotoxic. Spices are widely used on a daily basis around the world. Some of the major spices/active principles used in large quantities are turmeric (curcumins), ginger (gingerol, shaogol, zingerone), betel leaf (hydroxy chavicol) and catechu (catechin).With short-term mutagenic assay, these spices extract and their active principles are nonmutagenic. We have tested these compounds against well-known mutagenic/carcinogenic PAHs, benzo(a)pyrene (BaP) and dimethyl(a)benzanthracene (DMBA). Nontoxic doses of extracts of spices/principles, turmeric/curcumins, ginger/gingerol, shaogol, zingerone, betel leaf/hydroxy chavicol and catechu/catechin dose dependently decreased the mutagenicity of BaP and DMBA. The protective activities of these compounds were also confirmed by animal tumor models. Nitrite is a water pollutant that is a precursor of mutagenic/carcinogenic nitrosamines and nitrosoamides. Amines/amides are present in vegetables and cured meat. Human stomach maintains acidic conditions, favors the chemical reaction of nitrite with amines/amides to form mutagenic/carcinogenic nitrosamines/amides. We mimic these conditions and have shown that turmeric and ginger their active principles dose dependently block the formation of nitrosamines/amides. Further the human efficacy of turmeric extract and its principle curcumin was confirmed in cigarette and bidi smokers. Consuming turmeric and curcumin reduced excretion of mutagens in human smokers. Large quantity of active principle are present in these spices, turmeric - curcumin 2%-2.5%, ginger - gingerol, shaogoal, zingerone - 2%-2.5%, betel leaf - hydroxychavicol 5%-10% and catechu - catechu 40%-50%. Human consumption of these spices may play an important role reducing the harmful effects of environmental toxicants, thus reducing cancer and other age related human chronic degenerative diseases.