**Part 1**

**The Role of Folic Acid and Prevention of Neural Tube Disease** 

**1** 

**The Role of Folic Acid** 

*2Department of Biochemistry* 

*Puerto Rico* 

*1University of Puerto Rico, School of Medicine, Department of Pediatrics, Neonatology Section* 

 **in the Prevention of Neural Tube Defects** 

Lourdes García-Fragoso1, Inés García-García1 and Carmen L. Cadilla2

Folate is a water-soluble B vitamin that occurs naturally in food. Folic acid is the synthetic form of folate that is found in supplements and added to fortified foods. Folate gets its name from the Latin word "folium" for leaf. A key observation of researcher Lucy Wills nearly 70 years ago led to the identification of folate as the nutrient needed to prevent the anemia of pregnancy. Dr. Wills demonstrated that the anemia could be corrected by a yeast extract. Folate was identified as the corrective substance in yeast extract in the late 1930s, and was extracted from spinach leaves in 1941. Folate helps produce and maintain new cells. This is especially important during periods of rapid cell division and growth such as infancy and pregnancy. Folate is needed to make DNA and RNA, the building blocks of cells. It also helps prevent changes to DNA that may lead to cancer. Both adults and children need folate to make normal red blood cells and prevent anemia. Folate is also essential for the metabolism of

Folic acid (pteroylmonoglutamic acid), which is the most oxidized and stable form of folate, occurs rarely in food but is the form used in vitamin supplements and in fortified food products. Folic acid consists of a *p*-aminobenzoic acid molecule linked at one end to a pteridine ring and at the other end to one glutamic acid molecule. Most naturally occurring folates, called *food folate* in some reports, are pteroylpolyglutamates, which contain one to six additional glutamate molecules joined in a peptide linkage to the γ-carboxyl of glutamate (IOM, 1998). Mammals are able to synthesize the pteridine ring but are unable to couple it to other compounds and are thus dependent on either dietary intake or bacterial synthesis

Dietary folates are a complex mixture of pteroylglutamates of various chain lengths and with a variety of substitutions on the pteridine ring. More than 90% of dietary folates exist as pteroylpolyglutamates, while the remaining is pteroymonoglutamate. The process of folate absorption requires a process involving hydrolysis to convert it to the monoglutamate form in the gut before absorption. An intestinal brush border pteroylpolyglutamate

homocysteine, and helps maintain normal levels of this amino acid (NIH, n.d).

**1. Introduction** 

**1.1 What is folic acid?** 

within the intestine (Birn, 2006).
