College of Agriculture and Environmental Sciences

CEPHT Faculty

Shengmin Sang, Ph.D., associate professor specializing in functional foods, researches dietary exposure markers using metabolomic approaches, with the goal of identifying novel bioactive natural products that can be used in functional foods and dietary supplements to prevent chronic diseases such as cancer and diabetes.

Present areas of research focus on how post-harvest technologies affect the chemical profile, bioavailability and efficacy of the bioactive components in functional foods.

Specific projects in his lab involve:

• Purifying and identifying bioactive components from herbal medicine and functional foods.
• Standardization and quality control of herbal medicine and functional foods;
• Studying the bioavailability and biotransformation of bioactive food components in animals and humans.
• Studying the preventive effects of dietary polyphenols, such as tea catechins and apple polyphenols on the development of diabetic complications focusing on the trapping of reactive dicarbonyl compounds and the formation of Advanced Glycation End Products (AGEs) using in vitro and animal models.
• Developing new chemopreventive agents from dietary sources, such as gingerols and shogaols from ginger, pterostilbene from blueberry, theaflavins from black tea, and wheat bran oil from wheat bran using in vitro and animal models.
• Using a metabolomic approach to study dietary exposure markers.

Sang is a very productive natural product scientist. He has published over 100 peer-reviewed articles in reputable journals and 15 book chapters.

He was co-organizer of the symposium “Challenges in Chemistry and Biology of Herbs” at the American Chemical Society’s National Meeting in 2004, and co-edited a book titled “Herbs: Challenges in Chemistry and Biology” sponsored by ACS. He is organized another symposium titled “Reactive Carbonyl Species: Chemistry and Health Effects” for the ACS National Meeting in 2010.

He has received two U.S. patents titled “Benzotropolone derivatives and modulation of inflammatory response” (United States Patent Number: 7,087,790 B2. August 8, 2006 and 7,288,680. October 30, 2007). Sang’s research has been supported by research grants from NIH Botanical Center, NCI/NIH, U.S. Department of Agriculture, the U.S. Apple Association (USApple) and the Apple Products Research Education Council (APREC), as well as by a private company.

His outstanding research in the area of food and health was recognized with his winning in 2007 the Young Scientist Award of the Agricultural and Food Chemistry Division from the American Chemical Society; and in 2009, the Matthew Suffness Young Investigator Award, which is currently the highest honor for an investigator in the first ten years of his independent research career in the American Society of Pharmacognosy.

Sang obtained his Ph.D. as a natural product chemist from Shanghai Institute of Material Medicine, Chinese Academy of Sciences in 1999. From 1999-2003, he served as a postdoctoral research associate in the Department of Food Science at Rutgers University, and from 2003-2008 as an assistant research professor in the Department of Chemical Biology, School of Pharmacy. From 2008 - 2010, he was assistant professor in the Julius L. Chambers Biomedical/Biotechnology Research Institute at North Carolina Central University. He continues to serve as adjunct faculty in the Department of Chemical Biology, School of Pharmacy at Rutgers University and in the Department of Food, Bioprocessing and Nutritional Sciences at North Carolina State University.

Leonard L. Williams, Ph.D., professor and lead scientist for food safety at the Center for Excellence in Post-Harvest Technologies, specializes in microbiology. Williams examines the incidence of foodborne pathogens in fruits and vegetables, including salad crops, using molecular, immunological and epidemiological approaches, with the goal of identifying new strains and their ability to develop resistance to both natural and synthetically derived agents.

Current areas of research focus on determining the genetic diversity and antimicrobial profile of pathogens isolated from food and animal samples, as well as developing a rapid antimicrobial assay to determine the efficacy of natural and synthetic agents.

Active projects in the laboratory involve:

• Determining the mode of action of selected phytochemicals and bioactive compounds against Methicillin-resistant Staphylococcus aureus, Listeria monocytogenes and enterohemorrhagic E. coli (E. coli O157: H7).
• Use of novel non-thermal processing to inactivate food borne pathogens on the surfaces of produce.
• Developing new in vitro and in vivo animal models to determine the virulence of microorganisms (viral and bacterial) on host immunity.
• Using a molecular and immunological approach to study the role of phytochemicals on cell-mediated cytotoxicity and viability.
• Shelf-life studies involving fresh produce.
• Epidemiological approaches to food safety and food defense.
• Use of non-thermal technologies for the inactivation of food borne pathogens on the surfaces of fruits and vegetables.

Williams obtained his Ph.D. in food science, specializing in microbiology, from Alabama A&M University in 2000. From 2000-2005, he served as assistant professor of food microbiology and immunochemistry in the Department of Food and Animal Sciences, and from 2005-2008 as associate professor in the same department. In addition to his doctorate in food science, Williams also has a M.S. in animal health sciences from N.C. A&T.

Guibing Chen, Ph.D., assistant professor and lead scientist for food processing and engineering, is currently researching functional extruded foods, functional food processing using novel microgel capsules, and active and modified atmosphere packaging of fresh produce.

Prior to joining N.C. A&T’s Center for Excellence in Post-Harvest Technologies, he was a thermal process engineer at ConAgra Foods, working on retort sterilization of canned foods. His previous research involved various aspects of food processing, including mathematical and computer-aided modeling, rheological behavior of semi-solid foods, corn drying, microbial inactivation dynamics, thermal processing of canned foods, food extrusion, and novel gel capsule development.

Chen was the first researcher to develop a control strategy for automatically correcting process temperature deviations in continuous retort sterilization process. This work was awarded the first place in 2006 Charles R. Stumbo Student Paper Competition, organized by the Institute for Thermal Processing Specialists. His research has been published in prestigious food journals, including the Journal of Food Engineering, Food Research International, and the Journal of Cereal Science.

Chen earned his Ph.D. degree in Agricultural and Biological Engineering specializing in Food Processing from Purdue University. He also received M.S. and B.S. degrees in Chemical Engineering from Dalian University of Technology, China. Following his Ph.D. studies, he conducted postdoctoral research at the same University.