Capillary zone electrophoretic determination of the four vitamin C esters L-ascorbyl-2-phosphate, L-ascorbyl-2-sulfate, L-ascorbyl-2-diphosphate and L-ascorbyl-2-triphosphate in fish feed, plasma and tissue.

A new and fast method for the determination of L-ascorbyl-2-phosphate, the 2-diphosphate, 2-triphosphate and the 2-sulfate ester in feed, fish plasma and tissue samples by capillary zone electrophoresis is described. The substances were extracted with a 200 mM potassium phosphate buffer pH 4.0. Separation was achieved using a 50 microm uncoated fused-silica bubble capillary of 40 cm length to the detector, which was set at 254 nm, and a 80 mM tricine buffer at pH 9.2. Repeatability checked on a trout feed sample revealed a migration time variation of 1.2% (n=24) and an area calculation variation of 2.8% (n=24). Detector response for L-ascorbyl-2-phosphate was linear up to at least 100 microg ml(-1). After administration of a high dose of L-ascorbyl-2-phosphate to rainbow trout, the compound was found in the stomach and intestine but not in plasma, proving a fast conversion to vitamin C.

Delaying colostrum intake by one day impairs plasma lipid, essential fatty acid, carotene, retinol and alpha-tocopherol status in neonatal calves.

To study whether a delayed start of colostrum feeding in calves affects plasma lipids, fatty acids and fat-soluble vitamins, one group was fed colostrum (milkings 1-4) on d 1 and 2, then mature milk up to d 7, whereas two other groups were fed glucose or water on d 1, colostrum (milkings 1-4) on d 2 and 3 and then mature milk up to d 7. In calves fed colostrum on d 1, starting 5-7 h after birth, plasma concentrations of triglycerides, phospholipids, total cholesterol and of essential and nonessential fatty acids in triglyceride, phospholipid and cholesterol ester fractions as well as of carotene, retinol and alpha-tocopherol up to d 7 were significantly higher than in calves in which colostrum feeding started after >24 h of life. On the other hand, plasma concentrations of vitamin B-6, vitamin B-12 and folic acid were not influenced. Results indicated reduced efficiency of absorption of colostral fatty acids and of fat-soluble vitamins, but not of (selected) water-soluble vitamins, if colostrum is not fed on d 1 of life. In conclusion, colostrum intake within the first 24 h of life is required for an adequate plasma lipid, essential fatty acid, carotene, retinol and alpha-tocopherol status in the first week of life of calves.

Serum antioxidants and myocardial infarction. Are low levels of carotenoids and alpha-tocopherol risk factors for myocardial infarction?

BACKGROUND: In vitro, animal and epidemiological studies suggest that lipoprotein oxidation may play an important role in atherosclerosis. Antioxidants may protect against lipoprotein oxidation and in that way inhibit atherosclerosis and its clinical sequelae. To investigate this possibility, we examined the association between levels of several antioxidants and myocardial infarction using serum specimens collected 7 to 14 years before the onset of myocardial infarction. METHODS AND RESULTS: A nested case-control design was used. Cases and control subjects were selected from the 25,802 persons who had donated 15 mL of blood in 1974 for a serum bank. Cases comprised 123 persons with a subsequent first diagnosis of myocardial infarction who ranged from 23 through 58 years of age in 1974 and who had had their first diagnosis of myocardial infarction during 1981 to 1988. Two groups of control subjects matched to the cases for sex and age were selected from donors to the serum bank, one from those with hospital admissions during the same period and the other from the total group of donors. Sera were assayed for four carotenoids (beta-carotene, lycopene, lutein, and zeaxanthin), alpha-tocopherol, and cholesterol. Because associations with these serum nutrients showed similar trends whether based on hospital or community controls, the two control groups were combined. There was a significantly increasing risk for subsequent myocardial infarction with decreasing levels of beta-carotene in 1974 (P value for trend, .02) and a suggestive trend with decreasing levels of lutein (P = .09). When the results were stratified by smoking status, the excess risk of myocardial infarction associated with low serum levels of carotenoids was limited to smokers. A protective association with higher levels of alpha-tocopherol was suggested only among persons with high levels of serum cholesterol. CONCLUSIONS: Low serum levels of carotenoids were associated with an increased risk of subsequent myocardial infarction among smokers.

[Relationship between plasmatic lipids and fat soluble vitamins in Guatemalan periurban elderly]. / Relación entre lípidos plasmáticos y vitaminas liposolubles en anciano peri-urbanos de Guatemala.

The levels of plasmatic lipids and fat liposoluble vitamins were measured in 107 elderlies (29% males, 71% females) who were residents of a poor periurban neighborhood of Guatemala City. The age ranged between 60-103 years (means +/- sd 69 +/- 8). The mean and sd for the plasmatic levels of lipids and vitamins were (ranges in parenthesis): cholesterol 220 +/- 42 mg/dl (128 to 428); triglycerides: 189 +/- 92 mg/dl (54 to 513); retinol 50 +/- 16 ug/dl (4.5 to 103); beta-carotene 17 +/- 12 ug/dl (12 to 60), tocopherol 1.32 +/- 0.36 mg/dl (0.54 to 2.46). A significant correlation was found in both sexes between cholesterol and retinol (r = 0.3, p < 0.05) and cholesterol and tocopherol (r = 0.4, p < 0.05), triglycerides and retinol (r = 0.3, p < 0.05). Cholesterol and beta-carotene was also significant in women (r = 0.5, p < 0.05). The correlation between triglycerides and beta-carotene by gender was not significant.

Relación entre lípidos plasmáticos y vitaminas liposolubles en anciano peri-urbanos de Guatemala / Relationship between plasma lipids and fat soluble vitamins levels among Guatemalan periurban elderly

Se investigó el nivel de lípidos y vitaminas liposolubles así como su correlación en el plasma de 107 ancianos (29 por ciento de sexo masculino y 71 por ciento femenino) procedentes de "Guajitos", comunidad periurbana de Guatemala. Las edades oscilaron entre 60 a 103 años (promedio:69 ñ 8). Los promedios de niveles plasmáticos fueron: colesterol: 220 ñ42(128 a 428) mg/dl; trigliceridos: 189 ñ92 54 a 513) mg/dl; retinol 50 ñ 16 (4.5 a 103) mg/dl, B-carotenos: 17 ñ 12 (12-60) µg/dl, y tocoferol: 1.32 ñ 36 (0.54 a 2.46) mg/dl. Se encontró correlación significativa entre colesterol y retinol, colesterol y tocoferol, triglicéridos y retinol, triglicéridos y tocoferol en ambos sexos, así como entre colesterol y ß-carotenos en las mujeres. No se encontró correlación entre colesterol y ß-carotenos en hombres, ni entre triglicéridos y ß-carotenos en ambos sexos

Determination of vitamins A and E in liver tissue.

A simple, efficient and robust method for the simultaneous determination of the two vitamins A and E in liver tissue has been developed and evaluated. The assay consists of a saponification step followed by a single extraction of the resulting solution with a mixture of n-hexane/toluene. The vitamins are quantified in the extract using two separate HPLC lines running on straight phase mode. The eluted compounds were detected with a fluorescence detector. Recoveries of spiked samples were found to be 92.4% for vitamin A and 95.2% for alpha-tocopherol. The coefficient of variation was found to be +/- 4.27% for retinol and +/- 4.64% for alpha-tocopherol. The described analytical method has proven to be very effective and fast, enabling the processing of a large number of samples within a short period of time. It is highly specific and sensitive covering a wide range of different concentrations in the samples. It may be applied therefore in routine assays of samples with great variability concerning the vitamin concentrations in the tissue.

Simultaneous determination of retinol, tocopherols, carotenes and lycopene in plasma by means of high-performance liquid chromatography on reversed phase.

The determination of the vitamins A and E as well as of carotenes and lycopene is important for studies of cardiovascular diseases and cancer. A method for laboratory routine is reported to separate simultaneously retinol, tocopherols, alpha- and beta-carotene, lycopene and beta-cryptoxanthin in human plasma or serum by HPLC on reversed phase starting from one extract. Two detectors with programmable wavelength are used sequentially, a spectrophotometer for the detection of the carotenoids in the visible region and a fluorometer for the assay of retinol and the tocopherols.

Measurement of ascorbic acid and erythorbic acid in processed meat by HPLC.

A simple and efficient HPLC method is described to measure both ascorbic and erythorbic acid separately in processed meat products. The system used consisted of a reversed-phase column, a mobile phase containing an ion-pairing agent and ultraviolet detection. The procedure, which was checked on a variety of samples, was found to give reproducible and reliable results.

Production of a novel red pigment, rubrolone, by Streptomyces echinoruber sp. nov. I. Taxonomy, fermentation and partial purification.

A taxonomic study of Streptomyces X-14077 (NRRL 8144), which produces a water-soluble purple-red pigment complex, revealed it to be a new species which has been named Streptomyces echinoruber sp. nov. The pigment complex was produced in deep culture fermentation and isolated by solvent extraction and concentration. The major pigment component, rubrolone, has low toxicity and may have potential as a food coloring agent. It appears to be devoid of antibiotic activity.

Production of a novel red pigment, rubrolone, by Streptomyces echinoruber Sp. Nov. II. Chemistry and structure elucidation.

Streptomyces echinoruber sp. nov. produces several red pigments. The major component, rubrolone, has been identified as 8(R),9(R),10(S),10a(R)-tetrahydro-9,10,10a,11-tetrahydroxy-3,8-dimethyl-1-propyl-6aH(S)-pyrano[2",3":5',4]furo[2',3':5,6]azuleno[2,3-c]pyridine-5,13-dione (1) by single crystal X-ray analysis of a suitable derivative. A second pigment, B, is probably structurally closely related.