Tetrahydrobiopterin (BH4) serves as a critical co-factor for the endothelial nitric-oxide synthase (eNOS). A deficiency of BH4 results in eNOS uncoupling, which is associated with increased superoxide and decreased NO* production. BH4 has been suggested to be a target for oxidation by peroxynitrite (ONOO-), and ascorbate has been shown to preserve BH4 levels and enhance endothelial NO* producti...

As a response to high light, plants have evolved non-photochemical quenching (NPQ), mechanisms that lead to the dissipation of excess absorbed light energy as heat, thereby minimizing the formation of dangerous oxygen radicals. One component of NPQ is pH dependent and involves the formation of zeaxanthin from violaxanthin. The enzyme responsible for the conversion of violaxanthin to zeaxanthin ...

is an obligate nutrient for life, due to its key roles in myriad cellular processes. This vital transition metal is also an essential component of haemoglobin in red blood cells [3, 4], of which 200 billion new red cells are produced every day [5, 6]. It is well known that vitamin C (ascorbate) is crucial for collagen formation and the prevention of scurvy [2]. However, an underappreciated fact...

Plant foods were digested in vitro and the proportion of iron which diffused across a semi-permeable membrane was used as an index of Fe availability. The mean (with SEM) Fe diffusibility from a group of eighteen cereals, legumes and nuts was very low, 2.1 (0.25)%, whereas from a group of sixteen fruits and vegetables it was high, 31.7 (1.09)%. The difference between the two food groups was hig...

In an attempt to decrease ascorbate interference on the ion-chromatographic determination of urinary oxalate, we compared the effectiveness of four different methods for ascorbate elimination by analyzing a representative urine pool supplemented with successive ascorbate additions. Two of the methods--treatment with ferric ions or boric acid--have been described elsewhere; treatments with nitri...

2.1. Glutathione 2.1.A. Biological Functions 2.1.B. Biosynthesis 2.1.C. Degradation 2.1.D. Other Thiol-Based Redox Buffers 2.2. Ascorbate 2.2.A. Ascorbate Chemistry 2.2.B. Ascorbate Biosynthesis 2.2.C. Ascorbate Recycling 2.2.D. Ascorbate Transport 2.2.E. Importance of Ascorbate in Stress and Disease 2.3. Other Antioxidants 2.3.A. Lipid-Soluble Antioxidants 2.3.B. Water-Soluble Antioxidants 2.3...

Ascorbate, as a strong and active antioxidant, plays an important role in keeping human health. It helps promote iron absorption, increase antibody concentration and improve human immunity. Ascorbate is used to regenerate a-tocopherol (vitamin E), and remove radicals which could induce cancer and senescence. Ascorbate is beneficial to strengthen blood vessel and decrease cholesterol concentrati...

Background: Anaemia has significant impact on health of the fetus as well that mother. Increased need iron during pregnancy especially after 2nd trimester makes supplementation mandatory. Ferrous ascorbate is known to exist intact inside gastrointestinal tract due stable chelation with ascorbate. This compound does not dissociate any food inhibitors. The aim study effectiveness Ascorbate and su...

Oxidation and uptake of ascorbate show similar time courses in rat liver microsomal vesicles: a rapid burst phase is followed by a slower process. Inhibitors of ascorbate oxidation (proadifen, econazole or quercetin) also effectively decreased the uptake of ascorbate. The results show that dehydroascorbate is the transport form of ascorbate at the membrane of the endoplasmic reticulum.