Affiliations: Department of Food Science and Technology, School of
Agricultural Biotechnology and Center for Agricultural Biomaterials, Seoul
National University, Seoul 151-742, Republic of Korea | Division of Food Science, College of Life and
Environmental Sciences, Korea University, Seoul 136-713, Republic of
Korea
Note: [] Address for correspondence: Hyong Joo Lee, Ph.D., Department of
Food Science and Technology, School of Agricultural Biotechnology and Center
for Agricultural Biomaterials, College of Agriculture and Life Sciences, Seoul
National University, San 56-1, Shillim-dong, Gwanak-gu, Seoul 151-742, Republic
of Korea. Tel.: +82 2 880 4853; Fax: +82 2 873 5095; E-mail: leehyjo@snu.ac.kr
Abstract: The utilization of cacao bean husk (CBH), a by-product of chocolate
manufacture, would be both environmentally and economically beneficial. For
this purpose, a process for effectively separating and fractionating CBH
fractions having cancer preventive potential was developed in this study. For
screening the fractions with potent cancer preventive activity, we examined the
effect of extracts and fractions of CBH on the inhibition of gap-junction
intercellular communication (GJIC) and the DNA synthesis of cancer cells, both
of which are characteristics of the promotion and progression stages in
carcinogenesis. The extracts of CBH (especially, the 60% ethanol fraction after
extraction with 50% acetone) containing 43 wt.% polyphenol exerted an excellent
protective effect on H_2O_2-induced
inhibition of GJIC in WB-F344 rat liver epithelial cells as determined by the
scrape-loading/dye transfer assay. The enhancement of GJIC by the extracts of
CBH was approximately 10-fold higher than that of a well-known dietary
chemopreventive component, vitamin C. The extracts of CBH (especially, the 60%
ethanol fraction) also suppressed DNA synthesis in all liver, stomach, and
colon cancer cells as demonstrated by the ^3H-thymidine
incorporation assay, by approximately four-fold higher than that of vitamin C.
These results imply that the polyphenol extracts and fractions of CBH are
effective functional materials to be used in either preventing or inhibiting
cancer.
