Philipp W. Simon, Ph.D.

Room 203B Horticulture
1575 Linden Drive
Madison, WI 53706
608-262-1248
psimon@wisc.edu

Emphasis Group:
Human Nutrition

Principal Research Interest:
Biochemical genetics and breeding of carrots, alliums, potatoes and cucumber; genetic improvement of vegetable culinary and nutritional value

Research Summary:
The research emphasis of this laboratory is to understand the genetic influence upon nutritional quality and flavor of carrots, onions, garlic, and cucumbers. Carrots are the major sources of provitamin A carotenoids from vegetables and fruits in the U.S. We have developed carrot genetic stocks with 300 to 800 ppm carotenoids, in contrast to typical U.S. carrots that contain 70 to 100 ppm carotenoids. The usefulness of high-carotene carrots in helping alleviate vitamin A deficiency in developing areas of the world is being examined in international trials. In addition, carotene biosynthesis and genetics in carrot plants and tissue cultures are being examined. Deployment and evaluation of high-carotene carrots in vitamin A-deficient parts of the world is underway.

The contributions of volatile terpenoids and sugar to harsh flavor and sweetness, respectively, in carrot have been examined, and major genes controlling the type and amount of monoterpenoids, sesquiterpenoids, sucrose, and reducing sugars have been identified. The biochemical genetics of sucrose to reducing sugar ratios have proven particularly interesting since one gene, Rs, controls the balance of these sugars and these are the major storage carbohydrates of carrot roots.

Onion and garlic research is directed to determining the biochemical genetics of pungent flavor development. Genetic components of carbohydrate accumulation in potato tubers and acrylamide formation in potato chips are under study. Carotene levels in orange-fleshed cucumbers are also being investigated.

Representative Publications:

Kurilich  A.C., B.A. Clevidence, S.J. Britz, P.W. Simon, and J.A. Novotny.  Plasma and urine responses are lower for acylated vs. nonacylated anthocyanins from raw and cooked purple carrots.  J. Agric. Food Chem. 53: 6537 -6542. 2005.  

Santos, C.A.F.,  and P.W. Simon.  Heritabilites and miminimum gene number estimates of carrot carotneoids.  Euphytica 151: 79-86. 2006

Porter Dosti, M.  J. P. Mills, P.W. Simon, and S. A.Tanumihardjo,  Bioavailability of beta-carotene (betaC) from purple carrots is the same as typical orange carrots while high-betaC carrots increase betaC stores in Mongolian gerbils (Meriones unguiculatus) Brit. J. Nutrit. 96: 260-9.  2006

B.J. Just, C.A.F. Santos, M.E.N. Fonseca, L.S. Boiteux, B.B. Oloizia, and P.W. Simon. Carotenoid biosynthesis structural genes in carrot (Daucus carota): Isolation, sequence-characterization, single nucleotide polymorphism (SNP) markers and genome mapping. Theor. Appl. Genet.114: 693-704. 2007.

Cavagnaro, P.F. , A. Camargo, C. R. Galmarini and P. W. Simon. Effect of cooking on garlic (Allium sativum) antiplatelet activity and thiosulfinates content. J. Agric. Food Chem. 55:1280-1288. 2007.