Nutrition Research


Table of Contents


Vitamin D has long been recognized as a required prohormone responsible for intestinal absorption of dietary calcium and phosphorus. At one time an image of a child with bowing femurs was a reminder of the vitamin D deficiency epidemic in starving populations of developing nations. In recent years, a cancer epidemiology graph is the new hallmark of vitamin D deficiency. Epidemiological studies dating back to 1941 report observations that people living in northern latitudes of the United States were more susceptible to death from cancer than people living in the lower latitudes. There has been increased interest in vitamin D and its relationship to cancer since 1980, when researchers proposed metabolites of sunlight derived vitamin D, through their influence on calcium metabolism, as protective factors against colon cancer based on the decreasing gradient of colon cancer mortality rates from northern to southern United States.
Recent mainstream media attention regarding the evidence of vitamin D and its role in cancer prevention is encouraging the medical community to define recommended guidelines on circulating vitamin D levels from sunlight, fortified food, or supplemental sources. The synthesis, function, and role of vitamin D in disease prevention is explained in Vitamin D Deficiency and Prevention of Human Disease, while a complementary research article provides genomic evidence specifically documenting vitamin D as an environmental factor that influences the risk of multiple sclerosis, Expression of the Multiple Sclerosis-Associated MHC Class II Allele HLA-DRB1*1501 is Regulated by Vitamin D.
Sigma is committed to supporting your nutrition research with our large portfolio of vitamins, vitamin derivatives, and antibodies for investigating vitamin-related function and vitamin-binding proteins (see Vitamins and Related Products), as well as a large collection of supporting reagents, solvents, adsorbants, and Labware for Plant Bioactive Extraction and Isolation.
Visit the Nutrition Research Web Resource at This resource contains the Bioactive Nutrient Explorer, Plant Profiler monographs, and nutrition research products including biochemicals commonly found in plants, as well as kits for food analysis and stable isotopes for metabolomic studies. Sign up for the Nutrition Research community at and receive nutrition-related literature and e-mail updates.

Plant Bioactive Extraction and isolation

The extraction of plant material and isolation of plant constituents typically require tedious protocols that are essential to isolating biologically active compounds and understanding their role in disease prevention and treatment. Bioactives isolated from leaf, stem, root, bark, flower, fruit, seed, or other plant materials are often identified using a bioassay-guided approach. This type of approach is useful for the investigation of alkaloids, antioxidants, bioflavonoids, terpenoids, and other compounds as promising therapeutics from an immense pool of plant biodiversity. Sigma-Aldrich® offers many products for bioactive extraction, isolation, and purification:
  • Tissue grinders, homogenizers and microcentrifuges for preparing plant material
  • Acids, bases, and solvents for polar and nonpolar extraction Plant Bioactive Extraction and Isolation
  • Glassware for extraction, distillation, and fractionation methods
  • TLC plates for qualitative compound identification and isolation
  • Adsorbants and desalting columns for purification
The following tables and listings contain a small selection of Sigma-Aldrich products for sample preparation and isolation. For a complete listing of Labware, reagents, solvents, columns, and adsorbants, please visit our online product directory at