Dr. Xi Wang

Research Assistant Professor
Ph.D. Food Biochemistry
1999, Louisiana State University

Research Interests
Nutragenomics

Office: 220 Jordan Hall
Phone: (864) 656-1291
Email: xiw@clemson.edu

Research Activities

My primary research interest lies in using immunochemical and cell bioassays for the assessment of bioactive compounds, toxins and other biological compounds and evaluating their bioactivities and bioavailabilities. One of my current research projects is on gossypol, that is a polyphenolic aldehyde extracted from cotton plants and has been known with anti-fertility, anti-HIV, and antiproliferative properties on a variety of human cancer cell lines, including breast, prostate, uterus, pancreas and colorectal cell lines. However, little is known about its bioavailability, the molecular mechanism and the identities of genes involved in the gossypol-induced tumor cell death, or the molecular impact of such genes modulation. A two-step research strategy has been executed in my lab. First, my research group has successfully produced anti-gossypol polyclonal and monoclonal antibody and developed antibody-based ELISA methods that have significantly improved the detection limits restricted by conventional HPLC and AOCS spectrophotometric methods. This practical gossypol-ELISA method has attracted interest from cotton growers, breeders and processors, entomologists, and cancer researchers. A patent application based on the anti-gossypol monoclonal antibody was filed in 2005. Second, my lab is now investigating the mechanism(s) on how gossypol inhibits the growth of cancer cells and trypanosomes (causing sleeping sickness). We are using a combination of biochemical techniques to characterize relevant changes in gene expression profiles, which are expected to identify unanticipated molecular alterations resulting from the gossypol treatment. In addition, we are also investigating the gossypol’s functional mechanisms through studying changes of cell membrane lipids, protein and metabolomics upon gossypol treatment by high performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-EIMS) because the effects of gossypol on cells are membrane associated and are likely modulated by lipid signaling systems. Information obtained from these studies will give more insight on gossypol’s multi-facet functions. Since 01/2007, I was funded to start the project “add values to cottonseed products”, which aims to produce biodiesel economically from cottonseed oil, study the impact of inherent antioxidants (i.e. gossypol, carotene, vitamin E etc.) in the biodiesel on the engine performance, and simultaneously utilize the downstream products and the inherent bioactive compounds to improve the financial return to the cottonseed industry.

Natural bioactive compounds have gained increasing attention by nutritionists and medical researchers for their strong evidence-supported health benefits in the prevention of cancer, cardiovascular problems, and degenerative diseases. Many food grade antioxidants can scavenge free radicals in the human body and result in reduction of the free radical damage to biological molecular like lipids and DNA. My current research interest is on studying bioactivities of nutraceuticals and biomedicines via bioassay-oriented techniques and nutragenomics. In detail, my research group focuses on identification of bioactive compounds from natural resources with the aid of modern analytical instruments such as HPLC-MS and GC-MS, and assessment of their bioactivities and bioavailabilities by in vitro and in vivo bioassays, as well as biotechnology to better understand their roles in disease prevention and health promotion.

Moreover, my research group is developing value-added functional foods by integrating GRAS bioactive nutraceuticals to improve human health and performance based on our nutritional and biochemical research and understandings.

Since 2005, our research group has filed following patents:

1. Gossypol and gossypol derivatives as anti-trypanosomal agents. Xi Wang, James Morris, Feng Chen, Thomas Beckham. Utility Patent filed 04/2008. Clemson University.

2. Method of controlling insects in cotton. Xi Wang and Feng Chen. Utility patent filed, 03/2006; PCT application filed, 04/2007 (PCT/US2007/008512), Clemson University, Clemson, SC.

3. Gossypol hybridoma and monoclonal antibody therefrom. Provisional patent filed, 01/2005. Xi Wang, Feng Chen, Leslie C. Plhak. Clemson University, Clemson, SC.

4. Detection of small molecular weight chemicals using nanoparticle-based radioimmunoassay. Feng Chen, Xi Wang. Patent filed, 10/2005 (12/069,136). Clemson University, Clemson, SC.

Recent Publications

Xi Wang*, Thomas Beckham, James Morris, Feng Chen, and David Gangemi. 2008. Bioactivities of gossypol, 6-methoxy gossypol and 6,6’-dimethoxy gossypol. J. Agric. Food Chem. 56, 4393-4398.

Yongxiang Yu, Feng Chen, Xi Wang, Jeff Adelberg, Felix Barron, Yenhui Chen and HauYin Chung. 2008. Evaluation of antioxidant activity of curcumin-free turmeric (Curcuma longa L.) oil and identification of its antioxidant constituents. Submitted to ACS “Functional Foods”. In press.

Emppu Salonen,* Sijie Lin, Michelle L. Reid, Marcus Allegood, Xi Wang, Apparao M. Rao, Ilpo Vattulainen,* and Pu Chun Ke*. 2008. Real-Time Translocation of Fullerene Reveals Cell Contraction. Small (Nano Micro). Online available. Impact factor: 6.024

Huaping Zhang, Xi Wang, Feng Chen, Xiao M. Androulakis and Michael J. Wargovich. 2007. Anticancer activity of limonoid from Khaya senegalensis. Phytotherapy Research. 21, 731-734.

Zhigang Li, Xi Wang*, Feng Chen and Hyun-Jin Kim. 2007. Chemical changes and overexpressed genes in sweet basil (Ocimum basilicum L.) upon methyl jasmonate treatment. J. Agric. Food Chem. 55(3), 706-713.

Additional Publication Resources