Fatty acid profiles of major food sources of howler monkeys (Alouatta palliata) in the neotropics

Wild howler monkeys (Alouatta palliata) get most of their calories from carbohydrates (65%) and fats (18%) of native tropical plants, but little is known about their intake of individual fatty acids. The fatty acid composition of several natural food sources of howler monkeys collected in Panama was determined by gas-liquid chromatography. The predominant fatty acids were palmitic (30%), linoleic (23%), linoleic (23%), -linolenic (16%) and oleic (15%). Fatty acids with less than 16, and more than 18, carbon chains were uncommon (0–7%). Although total saturated fatty acids were high in some specific food sources (22–54% of total fatty acids and 8 energy %), most of the calories from fat in the animals' diets are derived from mono-and polyunsaturated fatty acids (9.75 energy %) All food sources had significant amounts of the -3 fatty acid, -linolenic acid (2.9 energy %). In terms of human diets, the howler monkey's fat consumption would not be considered atherogenic. Unless these animals show a particular adverse susceptibility to dietary fat, it is unlikely that their fat intake is the primary cause of the low, but significant, incidence of atherosclerosis that develops in these animals in the wild state.     

The effect of endotoxin on membrane fatty acid composition in BCG-sensitized mice

The effects of endotoxin on mouse liver phospholipid fatty acid composition have been investigated. Administration of endotoxin from Salmonella abortus equi led to a decrease in the polyunsaturated fatty acid content of livers from mice sensitized with Bacille Calmette Guérin (BCG). The content of arachidonic acid fell significantly in both the phosphatidylcholine and phosphatidylinositol fractions whereas in the phosphatidylethanolamine fraction the linoleic acid content was significantly reduced. The polyunsaturated fatty acids were replaced by increased amounts of oleic acid and palmitic acid, leading to a reduction in the polyunsaturated to saturated fatty acid ratio.     

The effect of endotoxin on membrane fatty acid composition in BCG-sensitized mice

Summary The effects of endotoxin on mouse liver phospholipid fatty acid composition have been investigated. Administration of endotoxin fromSalmonella abortus equi led to a decrease in the polyunsaturated fatty acid content of livers from mice sensitized with Bacille Calmette Guérin (GCG). The content of arachidonic acid fell significantly in both the phosphatidylcholine and phosphatidylinositol fractions whereas in the phosphatidylethanolamine fraction the linoleic acid content was significantly reduced. The polyunsaturated fatty acids were replaced by increased amounts of oleic acid and palmitic acid, leading to a reduction in the polyunsaturated to saturated fatty acid ratio.     

Lipoxygenase activity of wheat seeding chloroplasts]

Chloroplasts have been isolated from Wheat shoots by density gradient centrifugation. When added to a linoleic acid and Tween 20 suspension these chloroplasts induce an oxygen consumption. The hydroperoxides synthesized from linoleic and oxygen have been characterized by spectrophotometry and thin layer chromatography.     

Variation in the fatty acid composition of developing seeds of rapeseed

Summary A study was made of the variation in the fatty acid composition of the oil in the developing seed of the Rafal cultivar of theBrassica napus L. cultivated in central Italy. The oil content reaches its maximum level 60 days after the petals fall. The increase in the percentage of oleic acid is negatively correlated with the palmitic, stearic and linoleic acid content.     

Oyster mushroom (Pleurotus ostreatus) reduces the activity of 3-hydroxy-3-methylglutaryl CoA reductase in rat liver microsomes

The effect of dried oyster mushroom (Pleurotus ostreatus) on cholesterol (C) content in serum, in lipoproteins and in liver, and on the activity of 3-hydroxy-3-methylglutaryl CoA (HMG-CoA) reductase in liver microsomes, was studied in male rats (strain Wistar, initial body weight 75 g) fed on low-cholesterol (9 mg/100 g) and high-cholesterol (0.3%) diets. Addition of 5% oyster mushroom to both diets reduced significantly the C-content in serum (by 30%), in very-low- and low-density lipoproteins (in a 11 ratio to the decrease of total serum C) and in liver (by 50%), as well as the activity of HMG-CoA reductase (by more than 30%).     

Insect tissues,not microorganisms,produce linoleic acid in the house cricket and the American cockroach

Summary Biosynthesis of linoleic acid, 182(n–6), was unambiguously demonstrated to occur in the cockroach,Periplaneta americana, and the cricket,Acheta domesticus. Axenic tissue from both of these insect species was demonstrated by radio-gas-liquid chromatography (radio-GLC) and radio-high-performance liquid chromatography (radio-HPLC) to incorporate [1-¹⁴C]acetate and [1-¹⁴C]oleate into this essential fatty acid.This work was supported by the National Science Foundation under grant DCB-8914417. We would like to thank Coby Schal for his generous gift of American cockroaches and Tania Kellermeyer for her excellent technical assistance.     

Effects of 2-β-D-glucosyl-4-hydroxy-7-methoxy-1,4-benzoxazin-3-one onSchizaphis graminum (rondani) (insecta,aphididae) feeding on artificial diets

Summary 2--Glucosyl-4-hydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA-Glc), the main hydroxamic acid from maize and wheat, and its aglucone, decreased survival ofSchizaphis graminum reared on artificial diets. Both compounds were toxic for aphids and acted as feeding deterrents, at concentrations as low as 1 mM. The natural concentrations of glucosides of hydroxamic acids in wheat leaves reach up to 6 mmoles/kg fresh weight, thus falling within the range in which DIMBOA-Glc causes delecterious effects to diet-fed aphids.To whom correspondence should be addressed. THis work was supported by grants from International Foundation for Science (484), Universidad de Chile (N-1654) and the Agency for International Development.     

Diet influences the colonisation of Campylobacter jejuni and distribution of mucin carbohydrates in the chick intestinal tract

The objectives of this study were to evaluate the effect of diet on the colonisation by Campylobacter jejuni of the chick caeca, and to determine whether the viscosity of the intestinal contents and mucin carbohydrates were altered by the diet. The diets investigated were maize based, wheat-based or wheat-based supplemented with xylanase. The xylanase-supplemented diet reduced the viscosity and lowered the numbers of Camp. jejuni. Feeding the enzyme-supplemented diet increased the amount of neutral and sulphated mucins in the goblet cells of the small and large intestines and caecum. An abundance of sulphated and carboxylated mucins was seen in the surface goblet cells of the large intestine with the maize- and wheat-based diets. Both the diet supplemented with xylanase and the maize diets increased crypt-surface glycosylation of the sialic acid residues. The analysed data from the combined sites showed significant differences in the amount of neutral and acidic mucins when comparing the wheat and the wheat plus xylanase diets. However, no changes were shown in the staining intensity of sulphated mucins between the three diets. Significant differences in the glycosylation of sialic acid and in the N-acetylglucosamine residues were shown between dietary groups. These results provide evidence that the wheat diet supplemented with xylanase leads to greater changes in the mucin composition and carbohydrate expression of goblet cell glycoconjugates, which are associated with a reduction in intestinal viscosity and decreased numbers of Camp. jejuni.     

Activation of the carcinogen N-hydroxy-2-acetylaminofluorene by rat mammary peroxidase

A peroxidase preparation from rat mammary gland parenchymal cells, a target tissue of arylamine carcinogens, was shown to activate the carcinogen N-hydroxy-2-acetylaminofluorene via a nitroxyl free radical intermediate to the more active carcinogens nitrosofluorene and N-acetoxy-2-acetylaminofluorene. Hydrogen peroxide, cumene hydroperoxide, and linoleic acid hydroperoxide were effective as substrates. The antioxidants ascorbate, propyl gallate and reduced glutathione prevented the free radical activation route.     

Fatty acid modulation of antiestrogen action and antiestrogen-binding protein in cultured lymphoid cells

Nonsteroidal antiestrogens reversibly and specifically inhibited the proliferation of two estrogen receptor-negative lymphoid cell lines (EL4 and Raji) in a dose-dependent manner. [3H]Thymidine incorporation of concanavalin A-stimulated primary splenocytes was also inhibited by 10(-6) M clomiphene (1-[4-(2-diethylaminoethoxy)phenyl]-1,2-diphenyl-2-chloroethylene). The antiproliferative effect could be prevented by the simultaneous presence in the growth medium of 10(-5) M linoleic acid or 10(-5) M arachidonic acid but not by 10(-6) M estradiol. Both lymphoid cell lines had high affinity antiestrogen-binding sites whose affinity could be altered by conditions of growth. Growth of EL4 cells in RPMI 1640 medium supplemented with charcoal-pretreated 5% fetal calf serum (charcoal-stripped medium) resulted in significantly higher affinity (Kd 0.54 nM +/- 0.11 nM; n = 6) than growth in medium supplemented with untreated serum (complete medium) (Kd = 1.68 nM +/- 0.48 nM; n = 6) (p less than 0.001). This change in affinity was partly due to removal of fatty acids from the growth medium by charcoal pretreatment, since addition of 10(-5) M linoleic acid or 10(-5) M gamma-linolenic to charcoal-stripped medium decreased the affinity of the antiestrogen-binding protein. In contrast, growth in 10(-5) M stearic acid or 10(-5) M oleic acid did not significantly alter the affinity of the antiestrogen-binding protein, whereas 10(-5) M palmitic acid significantly increased its affinity. The same fatty acids were also tested for their intrinsic effects on EL4 cell proliferation. Oleic, linoleic and gamma-linolenic acids were growth stimulatory while stearic and palmitic acids were not. Thus linoleic and gamma-linolenic acids whose presence in the growth medium was associated with decreased affinity of [3H]tamoxifen (1-[4-(2-dimethylaminoethoxy)phenyl]-1,2-diphenylbut-1(Z)-ene) binding to the intracellular antiestrogen-binding protein were also growth stimulatory. Unsaturated fatty acids have previously been shown to inhibit binding of [3H]tamoxifen to the antiestrogen-binding protein in a cell-free system. The present observations demonstrate that unsaturated fatty acids also modify the affinity of the antiestrogen-binding protein in intact cells.     

Chemie und Stoffwechsel der Polyenfettsäuren

Summary The chemical structure of the polyenoic fatty acids occuring in organ phosphatides and in fish oils is reviewed. The double bonds of all these polyenoic acids are arranged in divinylmethane pattern. Except some of the C₁₆-polyenoic acids of fish oils, these polyenoic acids belong either to the oleic, linoleic or linolenic acid type and have chain lengths C₁₈, C₂₀, and C₂₂. Polyenoic acids of the oleic acid type are present only in small amounts in phosphatides of mammalian origin. Fish oils are lacking in these but predominantly contain polyenoic acids of the linolenic acid type.Metabolic studies have shown that polyenoic acids of linoleic acid type (e.g. arachidonic acid) originate from linoleic acid and those of the linolenic acid type (e.g. C₂₀-pentaenoic and C₂₂-hexaenoic acid) from linolenic acid-both supplemented exogenous-by extension of the carbon chain by acetate on the side of the carboxylic acid group and introduction of additional double bonds in the divinylmethane pattern directed toward the carboxylic acid group. There is some evidence, however, that a total synthesis of the polyenoic acids of the oleic acid type occurs in the animal body.The transformation of linolenic to C₂₂-hexaenoic acid and some intermediate reactans have been investigated more precisely by means of the tracer method. As far as the biosynthesis of the polyenoic fatty acids is concerned there are no fundamental differences in different vertebrates.

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Nach einem Vortrag auf der gemeinsamen Tagung der deutschen, französischen und schweizerischen Biochemiker in Zürich vom 10.–12. Oktober 1960.     

Activation of the carcinogen N-hydroxy-2-acetylaminofluorene by rat mammary peroxidase

Summary A peroxidase preparation from rat mammary gland parenchymal cells, a target tissue of arylamine carcinogens, was shown to activate the carcinogen N-hydroxy-2-acetylaminofluorene via a nitroxyl free radical intermediate to the more active carcinogens nitrosofluorene and N-acetoxy-2-acetylaminofluorene. Hydrogen peroxide, cumene hydroperoxide, and linoleic acid hydroperoxide were effective as substrates. The antioxidants ascorbate, propyl gallate and reduced glutathione prevented the free radical activation route.     

Insect tissues, not microorganisms, produce linoleic acid in the house cricket and the American cockroach

Biosynthesis of linoleic acid, 18:2 (n-6), was unambiguously demonstrated to occur in the cockroach, Periplaneta americana, and the cricket, Acheta domesticus. Axenic tissue from both of these insect species was demonstrated by radio-gas-liquid chromatography (radio-GLC) and radio-high-performance liquid chromatography (radio-HPLC) to incorporate [1-14C]acetate and [1-14C]oleate into this essential fatty acid.     

Lipid accumulation by a cellulolytic strain of Aspergillus niger.

Lipid accumulation by a cellulolytic mold, Aspergillus niger, was studied. The amount of lipid accumulated ranged from 13.6-16.6% on various carbon sources, namely glucose, xylose, avicel (microcrystalline cellulose) and bagasse (a natural lignocellulosic substrate). Neutral lipids, phospholipids and glycolipids of the mycelia varied from 41.0-46.2%, 34.9-38.4% and 18.7-22.6% of total lipids, respectively. Unsaturated fatty acids comprised around 80% of total fatty materials with linoleic and oleic acid predominating. Of the four nitrogen sources tested, NH4Cl was the best source for lipid synthesis from cellulose (bagasse). Optimum temperature range for growth and lipid synthesis was 25-30 degrees C.     

Fatty acid modulation of antiestrogen action and antiestrogen-binding protein in cultured lymphoid cells

Summary Nonsteroidal antiestrogens reversibly and specifically inhibited the proliferation of two estrogen receptornegative lymphoid cell lines (EL4 and Raji) in a dose-dependent manner. [³H]Thymidine incorporation of concanavalin A-stimulated primary splenocytes was also inhibited by 10^–6 M clomiphene (1-[4-(2-diethylaminoethoxy)phenyl]-1,2-diphenyl-2-chloroethylene). The antiproliferative effect could be prevented by the simultaneous presence in the growth medium of 10^–5 M linoleic acid or 10^–5 M arachidonic acid but not by 10^–6 M estradiol. Both lymphoid cell lines had high affinity antiestrogen-binding sites whose affinity could be altered by conditions of growth. Growth of EL4 cells in RPMI 1640 medium supplemented with charcoal-pretreated 5% fetal calf serum (charcoal-stripped medium) resulted in significantly higher affinity (K_d 0.54 nM±0.11 nM; n=6) than growth in medium supplemented with untreated serum (complete medium) (K_d=1.68 nM±0.48 nM; n=6) (p<0.001). This change in affinity was partly due to removal of fatty acids from the growth medium by charcoal pretreatment, since addition of 10^–5 M linoleic acid or 10^–5 M gamma-linolenic to charcoal-stripped medium decreased the affinity of the antiestrogen-binding protein. In contrast, growth in 10^–5 M stearic acid or 10^–5 M oleic acid did not significantly alter the affinity of the antiestrogen-binding protein, whereas 10^–5 M palmitic acid significantly increased its affinity. The same fatty acids were also tested for their intrinsic effects on EL4 cell proliferation. Oleic, linoleic and gamma-linolenic acids were growth stimulatory while stearic and palmitic acids were not. Thus linoleic and gamma-linolenic acids whose presence in the growth medium was associated with decreased affinity of [³H]tamoxifen (1-[4-(2-dimethylaminoethoxy)phenyl]-1,2-diphenylbut-1(Z)-ene) binding to the intracellular antiestrogen-binding protein were also growth stimulatory. Unsaturated fatty acids have previously been shown to inhibit binding of [³H]tamoxifen to the antiestrogen-binding protein in a cell-free system. The present observations demonstrate that unsaturated fatty acids also modify the affinity of the antiestrogen-binding protein in intact cells.     

Plasma and hepatic antioxidant control and vitamin A nutritional status

Twenty-seven rats were divided into three groups and fed on diets containing 0.3, 6 or 60 RE (retinol equivalent) retinyl palmitate/g food. After 7 weeks, hepatic vitamin A uptake was found to be more efficient in vitamin A-deficient rats than in rats given adequate vitamin A. We showed that during the metabolic adaptation of the animals to the level of vitamin A in the diet, extensive modifications occur in the antioxidant defences of the organism. In parallel with the increase in the level of vitamin A, the decrease in the level of -tocopherol in the plasma can bring about a greater susceptibility of the lipoproteins to oxidative stress. Similarly, the decrease in the hepatic -tocopherol level and in glutathione peroxidase activity leads to the weakening of the liver's antioxidant defences.     

Inhibition of lipid peroxidation by diterpenoid fromPodocarpus nagi

A diterpenoid, totarol (1), fromPodocarpus nagi was evaluated as an antioxidant. This diterpenoid inhibited autoxidation of linoleic acid. Mitochondrial and microsomal lipid peroxidation induced by Fe(III)-ADP/NADH or Fe(III)-ADP/NADPH were also inhibited. Nagilactone E (2), a norditerpene lactone isolated from the same source, had no antioxidative activity. Furthermore, totarol protected red cells against oxidative hemolysis. This diterpene was shown to be effective in protecting biological systems against oxidative stresses.