ARS | Publication request: Phenolic and Glycoalkaloid Levels of S. Jamesii Accessions and their Anti-Proliferative Effect on Human Prostate and Colon Cancer Cells In Vitro

Submitted to: Potato Association of America Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: April 15, 2008
Publication Date: April 1, 2009
Citation: Nzaramba, M.N., Reddivari, L., Bamberg, J.B., Miller, J.C. 2009. Phenolic and Glycoalkaloid Levels of S. Jamesii Accessions and their Anti-Proliferative Effect on Human Prostate and Colon Cancer Cells In Vitro [abstract]. Potato Association of America Proceedings. 86:154.

Technical Abstract: Some tuber-bearing wild potato species are higher in antioxidant activity (AOA), phenolics (TP) and glycoalkaloids (TGA >200 mg/kg) than the potato of commerce. Hence, use of wild species as parental material in breeding for high AOA and TP might result in progenies with high TGA, if the traits are positively correlated. Also, potato tuber extracts can reduce proliferation of prostate cancer cells. The objective of this study was to screen 92 S. jamesii accessions in the US Potato Genebank for AOA, TP, TGA, and determine their correlations, as well as antiproliferative and cytotoxic effects of 15 S. jamesii accession extracts (5 and 10 µg/ml) on human prostate (LNCaP) and colon (HT-29) cancer cells in vitro. TP was estimated using the Folin-Ciocalteau assay, and glycoalkaloids were analyzed with HPLC. Cell proliferation and cytotoxicity were measured with WST and LDH assays, respectively. Alpha-solanine and a-chaconine were the major glycoalkaloids observed. Most accessions were higher in the above traits than Atlantic, Red LaSoda, and Yukon Gold. More than 90% of S. jamesii accessions had TGA levels < 200 mg/kg, and TP was not significantly correlated (r = 0.132) with TGA. All accessions significantly reduced proliferation of HT-29 (5 & 10µg/ml) and LNCaP (10µg/ml) cells compared to the control (DMSO), but were not toxic. Therefore, since TP is not correlated with TGA, using wild accessions in breeding for increased health promoting compounds would not necessarily increase glycoalkaloids in newly developed potato cultivars. Also, S. jamesii accessions reduced colon and prostate cancer cell proliferation, and are not necessarily toxic to human cells in vitro.