Chlorophyll and Cancer

Chlorophyll and Cancer Connection, Nutrients and Therapies

Many studies in the area of cancer research are opening up new possibilities for cures and prevention measures. One area of research is directed at the effects that chlorophyll may have on cancer cells within the human body.

Research is being conducted to investigate whether chlorophyll has important cancer fighting factors that may play a role in the destruction of cancer cells or whether it is an effective preventive agent.

by Angela Sheppard

Chemistry and Education
Intensive research for naturally occurring plant products which reduce genotoxic effects are driven by the increasing exposure of humans to environmental toxins (Sarkar, 1994). Experimental evidence indicates a strong relationship and connection between diet and cancer prevention. One’s food choices have been consistently shown to be a determinant factor of human cancer risk (Arbogast, 1995).

A positive correlation was shown between the chlorophyll content of vegetable extract with the vegetables’ antimutagenic activity (Sarkar, 1994). Chlorophyll is of considerable interest as an anticarcinogenic substance because it is so abundant in the green vegetables that humans consume.

Chlorophyll also has shown no toxic effects to humans (Arbogast, 1995). It is not clear however whether effective uptake of chlorophyll through diet would be enough to protect against certain types of cancers or whether one would need to take supplements along with a balanced diet

(Arbogast, 1995)

Derivatives of chlorophyll may also be an important aid in preventing or managing cancer. Research indicates that foods yielding chlorophyll derivatives may play a major role in cancer prevention. Chlorophyll derivatives have a high affinity for tumor tissue in comparison to normal tissue (Chernomorsky, 1999).

Evidence suggests that individual chlorophyll derivatives as well as commercial derivatives of chlorophyll have cytotoxic and cytostatic activities against tumor cells (Chernomorsky, 1999). Mutagenic action of a number of direct acting carcinogens was reduced by both chlorophyll and chlorophyllin (Sarkar, 1994). The concentrations of chlorophyllin (CHL) used in studies are within the range of chlorophyll found in human foods (Arbogast, 1995).

Daily supplements of the chlorophyll derivative, chlorophyllin (CHL) can provide a way to prevent cancer by reducing DNA damage (Arbogast, 1995). The chlorophyllin copper complex (CHL) is a water-soluble version of chlorophyll and is a semi-synthetic prepared substance. CHL is the most common chlorophyll derivative used for cancer related studies (Chernomorsky, 1999). Most research was done using chlorophyllin because chlorophyll is chemically modified to chlorophyllin in the body during digestion. Chlorophyllin given in amounts to that of chlorophyll were equally effective in the studies (Sarkar, 1994).

CHL can be added to the diet very easily and may be safe and useful for effective prevention of cancer (Arbogast, 1995).

Researchers indicate that chlorophyllin acts as an interceptor molecule in order to block the absorption of aflatoxins (known carcinogens) and other cancer causing constituents in the diet (Arbogast, 1995). When chlorophyllin is administered along with a carcinogen, the chlorophyllin acts as an interceptor molecule forming a reversible complex with the carcinogen. Studies specifically confirm chlorophyllin as an interceptor molecule (Sarkar, 1994).

Research shows that chlorophyll demonstrated an interceptor effect on all carcinogens tested (Chernomorsky, 1999).

Studies show the formation of a complex noncovalent bond between the carcinogen and the chlorophyllin is a possible mechanism for “interceptor” effects of CHL (Chernomorsky, 1999). The stronger the complex formation the lower the amount of chlorophyllin needed to intercept the carcinogen (Sarkar, 1994). The complex formation is possibly due to planar surfaces of the compound binding with the chlorophyllin due to the hydrophobic interactions on the surfaces of the chlorophyllin and the compound (Sarkar, 1994).

Another way to view the intercepting action of chlorophyll and its derivatives is by molecular trapping (Sarkar,1994). This molecular trapping causes carcinogens to become unavailable to target cells. Trapping reduces the availability of the carcinogen to the organism and less of the organism is exposed to the carcinogen (Sarkar, 1994). In one particular study on Salmo gairdneri, Fingerling Rainbow Trout, CHL appeared to work only if the CHL and the carcinogen were present in the diet at the same time (Arbogast, 1995). The mechanism of the interceptor component of the CHL is expected to apply to humans as well (Arbogast, 1995).
Another possible explanation of the mechanism of the chlorophyll derivative activity is that some derivatives of chlorophyll may block enzymatic activation of the carcinogen preventing a potent version of the carcinogen from forming (Chernomorsky, 1999).
Chlorophyll is the green pigment in plants.

Chloroplasts contain several types of chlorophylls, which are specialized light gatherers. Dark leafy green vegetables contain abundant chlorophyll as seen by their dark green color. The structure of all chlorophyll contains a complex porphyrin ring structure and a long hydrophobic hydrocarbon attached to the ring structure. The function of the tail is to anchor the chlorophyll in the membrane (Taiz, 1991). The function of the porphyrin ring in the structure of chlorophyll is to absorb light (Ting, 1982).

The porphyrin ring also gives the chlorophyll its green color (Ross, 1985). Diagrams of chlorophyll a and b can be seen in Appendix A (Ross, 1985). Chlorophyllins are derivatives of chlorophyll that differ in that the central magnesium in the porphyrin ring is replaced by other metals. Other metals may include cobalt, copper, or iron (Sarkar, 1994).
A major process of biological importance involving chlorophyll is photosynthesis because it is the only process that can generate energy. Photosynthesis takes place in the chloroplast and means “synthesis using light”. The chemical reactions of photosynthesis are driven by absorbing sunlight and converting it to energy.

All of the plant pigments that are active in the photosynthesis process are located in the chloroplast and all pigments serve a specific function (Taiz, 1991). The mesophyll of the leaves is the most active photosynthetic tissue in higher structured plants (Taiz, 1991). The pigments located in thylakoid membranes are made mostly of chlorophyll a and chlorophyll b (Ross, 1985).

The goal of research in many canning and freezing industries is to keep the bright green color of the vegetables during the heating process and to better understand the chlorophyll reactions taking place during various processes. The degradation of the green chlorophyll pigments involves a number of reactions all of which are important because of the human dietary intake of vegetables which contain chlorophyll (Cano, 1991). Specific reactions in the degradation of chlorophyll entail the loss of green color during breakdown.

Chemically the degradation involves converting phaeophorbide, an oxygenase (PaO), to a linear product by cutting one of the bonds in the major porphyrin ring (Hortensteiner, 1998). The ring opening reaction is reflected in the yellowing process of the sample or plant (Hortensteiner, 1998). Chlorophyll is not broken down into the raw materials from which it was made (Hortensteiner, 1998).

Because of the importance of chlorophyll content in foods, it is important to look at the daily recommended amount of foods and determine whether these amounts possibly have cancer preventing potential because of the chlorophyll content.

This is interesting because cancer prevention may turn to dietary preventative measures to help combat cancer. The coloring and reactions in dark green foods are especially of interest because of their high chlorophyll content and may play a major role in cancer prevention.

Chlorophyll is abundant, non-toxic, and may be life saving.

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