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ABSTRACT: Purpose – The main purpose of this paper is to determine the content of amino acids, fatty acids and minerals in seven indigenous leafy vegetables (ILVs) in Ghana. Design/methodology/approach – Leaves from plants growing near Kumasi were milled to a fine powder, dried to constant weight in a vacuum desiccator, and analyzed for their content of the afore-mentioned nutrients. The plants were: Hibiscus sabdarifa, Hibiscus cannabinus, Amaranthus cruentus, Corchorus oliforius, Solanum macrocarpon, Xanthomosa sagittifolium and Vigna unguiculatus. Findings – All seven ILVs contained a large amount of protein (15.5-22.8 percent), which compared favorably to the essential amino acid pattern of a WHO standard. They all contained nutritionally useful amounts of a-linolenic acid and had an omega-6/omega-3 ratio of 0.1-0.9. The seven ILVs contained quantities of calcium, copper, iron, magnesium, manganese, molybdenum and zinc that could contribute significantly to satisfying an individual's need for these elements. Research limitations/implications – The presence of relatively large amounts of various nutritionally essential macro- and micronutrients in these seven ILVs does not necessarily mean these nutrients are bioavailable. Future research is required to determine the amounts of anti-nutrients (e.g. protease inhibitors, chelators) in these vegetables, and the extent to which their protein, lipid and mineral constituents are digested and/or absorbed. Originality/value – Since malnutrition (e.g. iron-deficiency anemia, rickets, zinc deficiency, protein-calorie malnutrition) is common in sub-Saharan Africa, the information which is provided should increase awareness among agricultural and public health officials of the nutritional value of seven underappreciated and underutilized ILVs that are indigenous to Ghana and many other parts of Africa.
British Food Journal 09/2010; 112(10):1102-1114. · 0.70 Impact Factor
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ABSTRACT: Dried seeds and nuts are widely consumed by indigenous populations of the western Sahel, especially those who inhabit rural areas. In light of the need for quantitative information regarding the content of particular nutrients in these plant foods, we collected dried pumpkin (Cucurbita spp) seeds and nuts of Cyperus esculentus in the Republic of Niger and analyzed them for their content of essential amino acids, minerals and trace elements, and fatty acids. On a dry weight basis, pumpkin seed contained 58.8% protein and 29.8% fat. However, the lysine score of the protein was only 65% relative to the FAO/WHO protein standard. The pumpkin seed contained useful amounts of linoleic (92 microg/g dry weight) and the following elements (on a microg per g dry weight basis): potassium (5,790), magnesium (5,690), manganese (49.3), zinc (113), selenium (1.29), copper (15.4), chromium (2.84), and molybdenum (0.81), but low amounts of calcium and iron. Except for potassium (5,573 microg/g dry weight) and chromium (2.88 microg/g dry weight), the C. esculentis nuts contained much less of these same nutrients compared to pumpkin seeds. In conclusion, pumpkin seeds represent a useful source of many nutrients essential to humans. The data in this report should of practical value to public health officials in rural areas of sub-Saharan Africa.
Materiae Vegetabiles 07/2006; 61(2):51-6. · 2.51 Impact Factor
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ABSTRACT: Dried seeds and nuts are widely consumed by indigenous populations of the western Sahel, especially those who inhabit rural areas. In light of the need for quantitative information regarding the content of particular nutrients in these plant foods, we collected dried pumpkin (Cucurbita spp) seeds and nuts of Cyperus esculentus in the Republic of Niger and analyzed them for their content of essential amino acids, minerals and trace elements, and fatty acids.On a dry weight basis, pumpkin seed contained 58.8% protein and 29.8% fat. However, the lysine score of the protein was only 65% relative to the FAO/WHO protein standard. The pumpkin seed contained useful amounts of linoleic (92μg/g dry weight) and the following elements (on a μg per g dry weight basis): potassium (5,790), magnesium (5,690), manganese (49.3), zinc (113), selenium (1.29), copper (15.4), chromium (2.84), and molybdenum (0.81), but low amounts of calcium and iron. Except for potassium (5,573μg/g dry weight) and chromium (2.88μg/g dry weight), the C. esculentis nuts contained much less of these same nutrients compared to pumpkin seeds.In conclusion, pumpkin seeds represent a useful source of many nutrients essential to humans. The data in this report should of practical value to public health officials in rural areas of sub-Saharan Africa.
Materiae Vegetabiles 05/2006; 61(2):49-54. · 2.51 Impact Factor
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ABSTRACT: Non-cereal plant foods in the Western Sahel of Africa contribute significantly to the diets of local residents, especially during periods of grain shortages. In this paper, we analyze four such plant foods including diyan kwakwa (nut of coconut palm, Cocos nucifera L.), muricin giginya (young shoot of Borassus aethiopum), tsamiya biri (fruit of the tree, Tamarindus indica), and yari (a mixture of lichens, mainly Rimelia reticulate) that grows on ebony trees (Diospyros mespiliformis). They were analyzed for their content of amino acids, fatty acids, and minerals. Although diyan kwakwa contained the highest protein content (27.1%), its protein quality fell below the WHO standard in 3 of 8 essential amino acid categories. Yari and muricin giginya contained moderate levels of good quality protein. Only diyan kwakwa contained calorically significant amount of total fatty acid (24.7%); however, none of the plants contained useful amounts of the essential fatty acids, linoleic acid, or alpha-linolenic acid. All four plants contained useful amounts of zinc (> 12 microg/g dry weight), while yari contained the most calcium (14.7 mg/g dry weight) and iron (1.41 mg/g), and diyan kwakwa the most copper. All the four plant foods contained lesser amounts of magnesium, molybdenum, or selenium. These data indicate that the four plants contain useful amounts of various essential nutrients that could supplement the diets of populations inhabiting the Western Sahel.
Materiae Vegetabiles 12/2005; 60(4):187-93. · 2.51 Impact Factor
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ABSTRACT: The date plum persimmon fruit (Diospyros lotus L., fam: Ebenaceae) is cultivated throughout northern of Turkey for its edible fruits. Sugars and organic acids were measured during fruit maturation and ripening using HPLC. The analyses showed that fructose and glucose were the main sugars accumulated in the fruit pulp. Fructose and glucose increased up to 43,552.8mg.100g–1fw and 35,450.8mg.100g–1fw respectively during fruit ripening. Sucrose content remained relatively low and decreased during ripening. The major organic acids found in date plum fruit were citric and malic acids, which increased through the immature and midripe maturity, and then the levels decreased in the overripe fruit. Palmitic acid (16:0), palmitoleic acid (16:1), stearic acid (18:0), oleic acid (18:1) and linolenic acid (18:3) were among the major fatty acids determined by GC throughout the maturation and ripening of the fruits. The levels of these fatty acids were found to be significantly different (P=0.05) between the three maturity stages. The fruits displayed the level of linoleic acid (0.7%) in low and -linolenic acid (17.8%) in higher quantities, and the combined levels of linoleic and -linolenic acid comprised 19% (120.1g.g–1 dw) of the total fatty acid content in the over ripened fruit. These results show that naturally parthenocarpic date plum fruits have high levels of sugars and organic acids and moderate levels of fatty acids that significantly changed during maturation and ripening. This information can be used by nutritionalists and food technologists to improve the nutrition of local people and develop food products that would be beneficial to human health.
European Food Research and Technology 01/2005; 221(1):113-118. · 1.57 Impact Factor
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ABSTRACT: The semi-nomadic cattle Fulani of northern Nigeria consume a diet rich in saturated fatty acids. Since the quality of an individual's dietary fat can influence the fatty acid composition of their membrane phospholipids (PL), we investigated the effect consumption of relatively large amounts of saturated fat might have on the fatty acid composition and fluidity of the serum PL of the Fulani. We obtained blood serum from 112 Fulani pastoralists (38 males, 74 females) 15-77 years of age and determined the serum fatty acid composition of the total PL fraction of each specimen. Our results indicate that the PL of the Fulani were enriched for saturated fatty acids. The unsaturated/saturated fatty acid ratio was 1.02 for the Fulani PL compared to 1.22-2.08 for seven other reference groups drawn from published reports. In addition, the mean melting point (MMP) of the fatty acyl chains of the serum PL of the Fulani was considerably higher than that of the reference populations (MMP, 30.6 degrees C versus 21.3-26.1 degrees C, respectively). The double bond index (DBI) of the serum PL of the Fulani was much lower than that of the PL of the groups against which comparisons were made (DBI, 0.98 versus 1.24-1.43, respectively). Since serum PL and tissue PL are in dynamic equilibrium, these findings suggest that the tissue PL of the Fulani we studied has considerably less fluid character than those of other populations. Since a variety of membrane functions depend on the fluid property of the acyl chains of their constituent PL, it is conceivable that certain critical membrane-dependent systems, including receptor-ligand interactions, solute transport, enzyme activity and lateral movement of macromolecules, are affected in the Fulani.
Prostaglandins Leukotrienes and Essential Fatty Acids 11/2003; 69(4):245-52. · 3.37 Impact Factor
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ABSTRACT: Fructose, glucose, and sucrose as the major soluble sugars, and citric, malic, and ascorbic acids as the major organic acids were determined by HPLC, and palmitic acid (16:0) and stearic acid (18:0), oleic acid (18:1), linoleic acid (18:2n-6) and linolenic acid (18:3n-3) as the major fatty acids were determined by GC in medlar (Mespilus germanica 'Dutch') fruit. The compositional changes of these constituents were monitored during the post harvest period of commercially sold Dutch form throughout its rapid ripening (fruit softening-darkening). Sucrose was highest at 1 WAH (228.4 mg/100 g fresh wt) and then decreased, remaining very low at 4 WAH (1.4 mg/100 g fresh wt). As for the levels of fructose and glucose, their levels shifted up to 2230.8 and 845.2 mg/100 g fresh wt at 2 and 3 WAHs, then the levels lessened to their lowest concentration. The levels of the three acids were high at the beginning, except malic acid level at 2 WAH, all acids leveled off through the latter weeks of post harvest period. In the fruit studied, the levels of saturated palmitic acid (16:0) and stearic acid (18:0), and unsaturated oleic acid (18:1), linoleic acid (18:2n-6) and linolenic acid (18:3n-3) were most abundant fatty acids detected throughout medlar ripening (pulp softening and darkening). The level of palmitic and stearic acids as well as the level of linoleic and linolenic acids were the highest at 1 WAH and then suddenly decreased as the medlar soften and the pulp becomes slightly (2 WAH) and fully (3 WAH) brown through 2 and 4 WAHs. In addition to these prominent fatty acids, a remarkable decrease was also obtained in the content of some other fatty acids (C10-15, C16:1, C20-24).
European Food Research and Technology 04/2003; 216(5):390-394. · 1.57 Impact Factor
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M G Paoletti,
E Buscardo,
D J VanderJagt,
A Pastuszyn,
L Pizzoferrato,
Y-S Huang, L-T Chuang,
M Millson,
H Cerda,
F Torres,
R H Glew
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ABSTRACT: For the Makiritare (Ye'Kuana) native people of the Alto Orinoco (Venezuela), earthworms (Anellida: Glossoscolecidae) are an important component of the diet. Two species in particular are widely consumed: 'kuru' (Andiorrhinus kuru n. sp.) and 'motto' (Andiorrhinus motto). We analysed eviscerated kuru body proper, and whole and smoked preparations of motto for their content of protein and amino acids, fatty acids and 20 minerals and trace elements. The samples contained large amounts of protein (64.5-72.9% of dry weight), essential amino acids, calcium and iron together with notable quantities of other important elements, indicating that these earthworms contain potentially useful quantities of many nutrients that are critical to the health of the humans who consume them.
Proceedings of the Royal Society B: Biological Sciences 03/2003; 270(1512):249-57. · 5.41 Impact Factor
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Ecology of Food and Nutrition 03/2003; 42(2):177-191. · 0.76 Impact Factor
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ABSTRACT: In a previous study conducted in Nigeria, we found that children with sickle cell disease (SCD) had exceedingly low total serum cholesterol levels (mean=100-102mg/dl). The fact that significant reductions in the levels of certain polyunsaturated fatty acids (PUFA) have been documented in the serum phospholipids of these same SCD subjects led us to inquire as to the fatty acid composition of the cholesteryl esters (CE) in their serum. Lecithin:cholesterol acyl transferase (LCAT), the enzyme in blood that catalyzes the reaction in which tissue cholesterol is acylated prior to its removal from cell membranes, is relatively specific for certain PUFA. CE in blood serum from 43 male and 42 female children with SCD, ages 4-18 years, and equal numbers of age- and gender-matched controls were analyzed for their fatty acid composition. Relative to the non-SCD controls, the CE of the SCD subjects contained 9% less linoleic acid, 16% less arachidonic acid, 40% less alpha-linolenic acid, 50% less eicosapentaenoic acid, and 36% less docosahexaenoic acid, but 15% more palmitic acid and 10% more oleic acid. Overall, the acyl chains of the CE of the SCD subjects were less fluid than those of the controls, as determined by comparison of their mean melting points (MMP) and double bond indices (DBI). MMP and DBI were both estimated from the individual constituent fatty acids comprising the CE acyl chains. The strongest correlations between MMP and fatty acid mole percent were seen with palmitic acid and linoleic acid. These results show that the fatty acid composition of the serum CE of children with SCD is abnormal relative to controls who do not have this hematologic disorder. We speculate that suboptimal fatty acid nutrition in Nigerian children with SCD compromises their ability to remove cholesterol from their tissues due to preference of the LCAT enzyme for PUFA, thereby accounting, in part at least, for the low total serum cholesterol levels one finds in children with SCD.
Prostaglandins Leukotrienes and Essential Fatty Acids 02/2003; 68(1):61-8. · 3.37 Impact Factor
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ABSTRACT: The purpose of this study was to determine the fatty acid composition of the serum phospholipids of children with sickle cell disease (SCD) in Nigeria and to compare the relative fluidity of the acyl chains of the serum phospholipids of controls versus the subjects with SCD. It is widely accepted that the fatty acid composition of an individual's serum phospholipids reflects that of their tissue phospholipids. An alteration in the fatty acid composition of membrane phospholipids could affect critical membrane-dependent enzymes and processes (e.g., ion and solute transport, hormone-receptor interactions, signal transduction pathways). We found a significant reduction in the content of polyunsaturated n-3 fatty acids in the phospholipids of subjects with SCD which could result in a reduction of the fluidity of their tissue membranes. Specifically, there was a 40-50% reduction in the proportion of total n-3 fatty acids in subjects with SCD. On the basis of calculated melting points and double bond indices of the acyl chains of the serum phospholipids, the phospholipids of the children with SCD are less fluid relative to those of their healthy counterparts. In addition, we determined that linoleic acid, arachidonic acid, and stearic acid were the major determinants of the fluidity of the acyl chains of the serum phospholipids of the healthy controls and children with SCD.
Prostaglandins Leukotrienes and Essential Fatty Acids 11/2002; 67(4):217-22. · 3.37 Impact Factor
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ABSTRACT: Phase angle, an impedance parameter used for nutritional assessment, is reflective of the capacitance properties of cell membranes. We have shown a significant correlation between the proportions of specific n-3 polyunsaturated fatty acids in the serum phospholipids of Nigerian children with sickle cell disease and their phase angles determined by bioelectrical impedance analysis.
Archives of Disease in Childhood 10/2002; 87(3):252-4. · 2.88 Impact Factor
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ABSTRACT: The fatty acid composition of medlar ( Mespilus germanica L. ) varied significantly among the ripening stages sampled at 157, 172 and 187 DAFs (days after full bloom). Twenty-one different fatty acids were detected in preclimacteric fruit and 17 when the climacteric began. Principal fatty acids, determined in medlar fruit harvested from October (157 and 172 DAFs) to November (187 DAF) were mainly palmitic acid (16:0), linoleic acid (18:2n-6), and a-linolenic acid (18:3n-3). While the content of saturated fatty acids [palmitic acid (16:0) and stearic acid (18:0)] increased, the content of the essential polyunsaturated fatty acids [linoleic acid (18:2n-6) and linolenic acid (18:3n-3)] decreased through ripening, in parallel with pulp darkening. The percentage of linoleic acid and a-linolenic acid in ripe, hard fruits was 60.0 and 13.5 % of dry wt at 157 DAF which decreased throughout ripening, remaining at 28.7 and 5.6 % of dry wt, respectively, in the fully softened and darkened pulp. A marked decreases in the double bond index, percentage of unsaturation and the ratio of unsaturation/saturation were also seen throughout the medlar ripening. The contribution of unsaturated fatty acid to the total fatty acid content decreased markedly as the medlar fruit became progressively softer and darkened.
La composición en ácidos grasos del níspero ( Mespilus germanica L. ) varió significativamente entre los estados de maduración muestreados a los 157, 172 y 187 DAFs (días después de la floración). Veinte y un ácidos grasos diferentes fueron detectados en el fruto preclimatérico y 17 cuando comenzó el climaterio. Los ácidos grasos principales encontrados en nísperos, recolectados desde Octubre (157 y 172 DAFs) hasta Noviembre (187 DAF), fueron principalmente ácido palmítico (16:0), ácido linoléico (18:2n-6), y ácido a-linolénico (18:3n-3). En tanto que el contenido en ácidos grasos saturados (ácido palmítico (16:0) y ácido esteárico (18:0)) aumentó, el contenido en ácidos grasos esenciales (ácido linoleico (18:2n-6) y ácido linolénico (18:3n-6)) disminuyó durante la maduración, en paralelo con el oscurecimiento de la pulpa. El porcentaje de ácido linoleico y de ácido a-linolénico en frutos maduros sin reblandecer fue de 60.0 y 13.5 % del peso seco a 157 DAF, disminuyendo durante la maduración, y permaneciendo a 28.7 y 56 % del peso seco, respectivamente, en la pulpa completamente blanda y oscura. También se observó durante la maduración del níspero una marcada disminución en el número de dobles enlaces, en el tanto por ciento de instauración y en la relación instauración / saturación. La contribución de los ácidos grasos insaturados al contenido de ácidos grasos totales disminuyó marcadamente cuando el níspero comenzó progresivamente a reblandecerse y oscurecerse.
Grasas y Aceites. 01/2002;
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ABSTRACT: Conjugated linoleic acid (CLA; 18:2) refers to a group of positional and geometric isomers derived from linoleic acid (LA; delta9,12-18:2). Using a growing baker's yeast (Saccharomyces cerevisiae) transformed with human elongase gene, we examined the inhibitory effect of CLA at various concentrations (10, 25, 50, and 100 microM) on elongation of LA (25 microM) to eicosadienoic acid (EDA; delta11,14-20:2). Among four available individual CLA isomers, only c9,t11- and t10,c12-isomers inhibited elongation of LA to EDA. The extent of inhibition (ranging from 20 to 60%) was related to the concentration of CLA added to the medium. In the meantime, only these two isomers, when added at 50 microM to the media, were elongated to conjugated FDA (c11,t13- and t12,c14-20:2) by the same recombinant elongase at the rate of 28 and 24%, respectively. The inhibitory effect of CLA on LA elongation is possibly due to competition between CLA isomers and LA for the recombinant elongase. Thus, results from this study and a previous study suggest that the biological effect of CLA is exerted through its inhibitory effect on delta6-desaturation as well as elongation of LA which results in a decrease in long-chain n-6 fatty acids and consequently the eicosanoid synthesis.
Lipids 11/2001; 36(10):1099-103. · 2.13 Impact Factor
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ABSTRACT: Milk was collected from 36 Nepalese women, 15 to 32 years of age, in order to investigate relationships between the proportions of intermediate chain-length (C10-C14) fatty acids and critical n-3 and n-6 polyunsaturated fatty acids in the milk lipids they were producing. Serum was also obtained from these lactating women and the fatty acid composition of their serum phospholipid fraction was determined and compared with that of the corresponding milk lipid fraction. Compared to women in technologically advanced parts of the world, the serum phospholipids of the Nepalese women contained nutritionally adequate proportions of linoleic acid (LA) (16.8%), alpha-linolenic acid (ALA) (0.53%), arachidonic acid (AA) (5.69%), and docosahexaenoic acid (DHA) (1.42%). However, although the milk lipids contained adequate proportions of ALA (1.81%), AA (0.43%), and DHA (0.23%), the lipids contained low to moderate percentages of LA (mean, 9.05%). Positive correlations were observed between the proportions of AA (P=0.001, r=0.50) and ALA (P=0.03, r=0.36) in the serum phospholipids and milk lipids of the women. As the proportion of C10-Cl4 fatty acids in the milk lipids increased from 10% to 40%, there was preferential retention of three critical n-3 and n-6 fatty acids (ALA, AA, and DHA) at the expense of two relatively abundant nonessential fatty acids, namely stearic acid and oleic acid. In addition, using fatty acid melting point data and the mol fraction of the 9 most abundant fatty acids in the milk, we estimated the mean melting point (MMP) of the milk lipids of the Nepalese women. The MMPs ranged from 29.3 to 40.5 degrees C (median, 35.5 degrees C). These results indicate that: 1) the levels of AA and ALA in the blood of lactating mothers influence the levels of these fatty acids in the milk they produce; 2) when the mammary gland produces a milk that is rich in C10-Cl4 fatty acids, it somehow regulates triglyceride synthesis in such a way as to ensure that the milk will provide the exclusively breast-fed infant with the amounts of the critical n-3 and n-6 fatty acids it requires for normal growth and development; and 3) the melting point of the milk lipid fraction is determined mainly by the mol % of the intermediate chain-length (C10-C14) fatty acids, oleic acid, linoleic acid, and alpha-linolenic acid.
Prostaglandins Leukotrienes and Essential Fatty Acids 10/2001; 65(3):147-56. · 3.37 Impact Factor
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ABSTRACT: Long-chain polyunsaturated fatty acids (LC-PUFA) are important components of cellular structure and function. Most of LC-PUFA are derived from linoleic acid and alpha-linolenic acid. In plants and fungi, these two acids can be synthesized from oleic acid via the action of two enzymes, delta12 and delta15-desaturases. Due to lack of these enzymatic activities and the ability to synthesize these two essential fatty acids, animals must obtain them from the diet. In this report, we demonstrated the expression of a fungal delta12-desaturase gene in mouse L cells incubated in serum-free medium. The results showed a significant increase in the amount of linoleic acid with a concomitant decrease of oleic acid in cellular lipids. Most of the newly formed linoleic acid was incorporated into cellular phospholipids, particularly phosphatidylcholine. The increase of linoleic acid provided the substrate for the endogenous synthesis of (n-6) LC-PUFA, such as eicosadienoic acid (EDA), dihomo-gamma-linoleic acid (DGLA) and arachidonic acid (AA). Prolonged incubation further increased the levels of linoleic acid derived from oleic acid by the action of delta12-desaturase, and the levels of 20:2n-6 produced from linoleic acid by the action of the endogenous elongase. However, prolonged incubation suppressed significantly the formation of DGLA and AA. In a separate study, a fungal delta6-desaturase gene has also been expressed in the mouse L cells incubated in serum-containing medium. The result shows a significant increase in levels of 20:3n-6 and 20:4n-6. These findings demonstrate that through genetic modification, it is possible to (1) generate cell lines which no longer require dietary 'essential' fatty acids and (2) alter the endogenous fatty acid metabolism to enhance the production of LC-PUFA and their derivatives.
Molecular and Cellular Biochemistry 04/2001; 219(1-2):7-11. · 2.06 Impact Factor
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ABSTRACT: Conjugated linoleic acid (CLA; 18:2), a group of positional and geometric isomers of linoleic acid (LA; 18:2n-6), has been shown to modulate immune function through its effect on eicosanoid synthesis. This effect has been attributed to a reduced production of n-6 polyunsaturated fatty acid (PUFA), the precursor of eicosanoids. Since delta6-desaturase is the rate-limiting enzyme of the n-6 PUFA production, it is our hypothesis that CLA, which has similar chemical structure to LA, interacts directly with delta6-desaturase. A unique and simple model, i.e., baker's yeast (Saccharomyces cerevisiae) transformed with fungal delta6-desaturase gene, previously established, was used to investigate the direct effect of CLA on delta6-desaturase. This model allows LA to be converted to y-linolenic acid (GLA; 18:3n-6) but not GLA to its metabolite(s). No metabolites of CLA were found in the lipids of the yeast transformed with delta6-desaturase. The inability to convert CLA to conjugated GLA was not due to the failure of yeast cells to take up the CLA isomers. CLA mixture and individual isomers significantly inhibited the activity of delta6-desaturase of the transformed yeast in vivo. Even though its uptake by the yeast was low, CLA c9,t11 isomer was found to be the most potent inhibitor of the four isomers tested, owing to its high inhibitory effect on delta6-desaturase. Since CLA did not cause significant changes in the level of delta6-desaturase mRNA, the inhibition of GLA production could not be attributed to suppression of delta6-desaturase gene expression at the transcriptional level.
Lipids 03/2001; 36(2):139-43. · 2.13 Impact Factor
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ABSTRACT: Incorporation of exogenous cholesterol was compared in human adenocarcinoma colon cells (Caco-2) after incubation with 100 microM of either linoleic acid (LA, 18:2n-6), gamma-linolenic acid (GLA, 18:3n-6), arachidonic acid (AA, 20:4n-6) or adrenic acid (or n-6 docosatetraenoic acid, DTA, 22:4n-6). In both cells 7 days after seeding and 14 days after confluency, incubation with LA significantly raised the proportion of 18:2n-6 but not its long-chain metabolites in cellular phospholipid. Incubation with GLA increased the levels of 18:3n-6, 20:3n-6, and 20:4n-6. Incubation with AA increased the levels of 20:4n-6 and 22:4n-6, and incubation with DTA increased the levels of 22:4n-6 as well as its retro-conversion metabolite, 20:4n-6. A subsequent addition of cholesterol (180 microM) to the medium significantly raised the cellular cholesterol level but less so in the cells 7 days after seeding incubated with GLA. The increase in cellular cholesterol level was generally greater in the cells of 7 days after seeding, particularly those incubated with long-chain highly unsaturated n-6 fatty acids, than in those of 14 days after confluency. These findings suggest that the cell growth and the extent of unsaturation in cell membrane phospholipid fatty acids modulate the incorporation of the exogenous cholesterol into the Caco-2 cells.
Bioscience Biotechnology and Biochemistry 01/2001; 64(12):2538-42. · 1.28 Impact Factor
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ABSTRACT: We previously reported that, relative to milk of women elsewhere in the world, the lipid fraction of milk of Fulani women in northern Nigeria contained relatively low proportions of alpha-linolenic acid and docosahexaenoic acid (DHA). This led us to question the essential fatty acid status of Fulani infants and the relation between the proportion of critical n-3 and n-6 fatty acids in the serum phospholipids of the mothers, their milk, and the serum phospholipids of their exclusively breast-fed infants. We were also interested in the effect de novo intermediate chain length-fatty acids (C10-C14) had on the proportions of critical and non-essential fatty acids in milk. Capillary gas-liquid chromatography was used to analyze the fatty acid content of the total milk lipids of 34 Fulani women, as well as the fatty acid content of serum phospholipids of the women and their breast-fed infants during the first 6 months of life. The proportions of critical n-3 and n-6 fatty acids in the milk of the Fulani women were adequate, but the proportions of these same fatty acids were low in their exclusively breast-fed infants. The serum phospholipids of the infants contained 18.8% linoleic acid, 0.13% alpha-linolenic acid, 12.8% arachidonic acid, and 3.40% DHA, whereas, the mean percentages of linoleic, alpha-linolenic, arachidonic and DHA in the serum phospholipids of the Fulani mothers' were 21.4, 0.20, 9.79, and 1.97, respectively. There was a strong positive correlation between fatty acid content of serum phospholipids of Fulani women and the fatty acid content of their milk lipids. As the proportion of C10-C14 fatty acids in the milk lipids increased, the proportions of critical n-3 and n-6 fatty acids in milk remained relatively constant; however, proportions of three non-essential fatty acids decreased dramatically. C10-C14 fatty acids do not appear to displace critical n-3 and n-6 fatty acids in milk.
Early Human Development 01/2001; 60(2):73-87. · 2.05 Impact Factor
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ABSTRACT: The milk of 89 women in northern Nigeria was analyzed for the fatty acid composition of the total milk lipids, and assessed for the effect nutritional status has on the conservation of essential and non-essential fatty acids when the proportions of C(10)-C(14)fatty acids are increased. The women were stratified on the basis of their body mass index, and calculations were made to estimate the effects of a 3.3-fold increase in the proportion of C(10)-C(14)fatty acids on the proportion of alpha-linolenic acid, docosahexaenoic acid, linoleic acid and arachidonic in total milk lipids. In the well-nourished group (group III, body mass index >23 kg/m(2)), the critical n-3 and n-6 fatty acids were not conserved, while in poorly nourished women (group I, body mass index <19 kg/m(2)), marked conservation of alpha-linolenic acid, docosahexaenoic acid, arachidonic acid, and palmitic acid was seen. Poor nutritional status of the mother appears to promote selective retention of critical essential and non-essential fatty acids in the milk lipid fraction.
Prostaglandins Leukotrienes and Essential Fatty Acids 11/2000; 63(4):195-202. · 3.37 Impact Factor
