Bioactive Compounds from Glanded and Glandless Cottonseeds

Cottonseeds are classified as glanded or glandless seeds. Due to presence of toxic gossypol in the glanded cotton, the use of cottonseed is limited to feeding cows. To explore the potential use of glandless cottonseed which has only trace amount of gossypol, we investigated the cytotoxicity and gene expression modulation of ethanol extracts from glandless cottonseed along with those from glanded cottonseed and compared directly with gossypol and lipopolysaccharide (LPS) in mammalian cells. Cottonseeds were separated into coat and kernel fractions. Both fractions were homogenized in acetic acid, defatted with chloroform and hexane and extracted with ethanol. The ethanol extracts were reconstituted in DMSO before being added to human cancer cells and mouse macrophages using gossypol and LPS as controls. Cell cytotoxicity and gene expression were determined with MTT and qPCR assays. Ethanol extracts from glanded and glandless cottonseed kernels and gossypol significantly decreased breast cancer cell mitochondrial activity. Ethanol extract from glanded cottonseed kernel and gossypol also significantly decreased pancreas cancer cell mitochondrial activity. These results suggest that ethanol extracts from cottonseeds, like gossypol, contain anticancer activities. No cytotoxicity effect was observed in macrophages treated with extracts from glandless cottonseed coat or kernel, or glanded cottonseed coat, but glanded cottonseed kernel extract inhibited mitochondrial activity by 40%. LPS did not show toxic activity but gossypol inhibited cell viability. Cottonseed extracts and gossypol increased the expression of antiinflammatory tristetraprolin, proinflammatory Tumor necrosis factor, and oil biosynthetic enzyme diacylglycerol acyltransferases in the macrophages. These results suggest that glandless cottonseed extract is harmless towards macrophages but glanded cottonseed extract from its kernel, like gossypol, is harmful to the immunological cells, and that ethanol extracts from cottonseed, especially glandless cottonseed may have health/nutritional benefits for inflammation-related diseases. The overall results suggest that cottonseed extracts contain anticancer activities and can modulate immunological function.