Composition and variability of the branched-chain fatty acid fraction in the milk of goats and cows

Enzymatic synthesis of branched chain fatty acid-enriched structured triacylglycerols via esterification with glycerol

While branched-chain fatty acids (BCFA)-enriched triacylglycerols (TAG) has various health benefits, its preparation has not been reported. This study aimed to synthesize high-purity BCFA-enriched structured TAG. First, BCFA was enriched from lanolin through saponification, calcification, and urea complexation. Next, BCFA-enriched TAG was synthesized by enzymatic esterification of BCFA and glycerol. Then, lipases were screened by molecular docking and practical experiments, which suggested that Lipozyme 435 was the best lipase for esterification since it had the lowest binding energy. Structured TAG containing 92.23% BCFA was synthesized under conditions optimized by single-factor experiments. Furthermore, molecular distillation was adapted to remove excess fatty acids and small molecule impurities. Finally, high-purity BCFA-enriched structured lipid containing 70.26% TAG was obtained. Overall, this study successfully developed a method for synthesizing BCFA-enriched structured TAG, which holds great promise for applications in value-added foods.

Characterization of fecal branched-chain fatty acid profiles and their associations with fecal microbiota in diarrheic and healthy dairy calves

Branched-chain fatty acids (BCFA) have recently been reported to play a role in human gut health during early life. However, little information is available on the fecal BCFA profiles in young ruminants and whether they are associated with the development of neonatal calf diarrhea. The objectives of this study were to (1) characterize BCFA profiles in feces collected from young calves, (2) compare the fecal BCFA composition between diarrheic and nondiarrheic dairy calves, and (3) explore the potential relationships between BCFA and microbiota in the feces. A total of 32 male Holstein dairy calves (13 ± 3 d old) with the same diet management were grouped as diarrheic (n = 16) or healthy (n = 16) based on fecal score (determined by liquid fecal consistency with some solid particles); diarrhea cases were defined as fecal score ≥2 for at least 2 d. Fecal samples were collected on the seventh day after calf arrival, and the fecal BCFA and microbial profiles were assessed using gas chromatograph and amplicon sequencing, respectively. In total, 7 BCFA were detected in the feces of all dairy calves; however, the concentrations of fecal BCFA differed between diarrheic and nondiarrheic calves. Specifically, the concentrations of iso-C16:0, iso-C17:0, anteiso-C17:0, and total even-chain BCFA were significantly higher in the feces of diarrheic calves. When the associations between BCFA and bacteria were studied, the relative abundance of Eggerthella was positively correlated with the concentrations of iso-C16:0 (ρ = 0.67), iso-17:0 (ρ = 0.77), anteiso-C17:0 (ρ = 0.73), and iso-C18:0 (ρ = 0.65), whereas the relative abundance of Subdoligranulum was positively correlated with the concentrations of iso-C14:0 (ρ = 0.62), iso-C15:0 (ρ = 0.78), and anteiso-C15:0 (ρ = 0.63). Use of random forest algorithm showed that BCFA such as anteiso-C15:0, iso-C16:0, iso-C17:0, iso-C18:0, and total even-chain BCFA could be used as biomarkers to differentiate diarrheic calves from healthy ones. Our findings generated fundamental knowledge on the potential roles of BCFA in neonatal calf gut health. Follow-up studies with larger animal populations are warranted to validate the feasibility of using BCFA as indicators of health status in neonatal calves.

Very Long-Chain Branched-Chain Fatty Acids in Chia Seeds: Implications for Human Use

Dairy and fermented foods are common sources of dietary branched-chain fatty acids (BCFA) of chain lengths C13-C18 serving a putative prebiotic role and a component of human integument. Few studies have reported on nonfermented plant-derived BCFA in human diets or cosmetics. A three-ion monitoring method was adapted to confirm branch position of ultratrace (<0.01%, w/w) BCFA. We identified chia as a new source of BCFA with C15-C35 chain lengths. Surprisingly, even-numbered very long-chain BCFA (VLC BCFA), anteiso-22:0, anteiso-24:0, and anteiso-26:0 were unequivocally identified in natural products for the first time. Plant-derived BCFA are predominantly anteiso, in contrast with similar iso and anteiso levels in ruminant and fermented foods. Chia seeds contain 0.4% BCFA, w/w of total fatty acids, or 32 mg BCFA in a food serving, surpassing other plant oils. Topical administration of chia seed oil containing VLC BCFA may have a role in skin and hair functionality.

Effect of Rearing System on the Straight and Branched Fatty Acids of Goat Milk and Meat of Suckling Kids

Goat meat is considered healthy because it has fewer calories and fat than meat from other traditional meat species. It is also rich in branched chain fatty acids that have health advantages when consumed. We studied the effects of maternal milk and milk replacers fed to suckling kids of four breeds on the straight and branched fatty acid compositions of their muscle. In addition, the proximal and fatty acid compositions of colostrum and milk were studied. Goat colostrum had more protein and fat and less lactose than milk. Goat milk is an important source of healthy fatty acids such as C18:1 c9 and C18:2 n–6. Suckling kid meat was also an important source of C18:1c9. Dairy goat breeds had higher percentages of trans monounsaturated fatty acids (MUFAs) and most of the C18:1 isomers but lower amounts of total MUFAs than meat breeds. However, these dairy kids had meat with a lower percentage of conjugated linoleic acid (CLA) than meat kids. The meat of kids fed natural milk had higher amounts of CLA and branched chain fatty acids (BCFAs) and lower amounts of n–6 fatty acids than kids fed milk replacers. Both milk and meat are a source of linoleic, α-linolenic, docosahexaenoic, eicosapentaenoic and arachidonic fatty acids, which are essential fatty acids and healthy long-chain fatty acids.

High levels of branched chain fatty acids in nātto and other Asian fermented foods

The mean intake (500 mg/day) of branched chain fatty acids (BCFA) in western countries is from dairy products and beef. We hypothesized that Asian countries with low dairy consumption have an alternative source of BCFA and report the characterization of nātto and selected fermented foods for BCFA content. Nātto BCFA averaged 0.6 (range 0.21-1.43) mg BCFA per g natto (wet weight) and was highly variable. Nātto major BCFA are C14-17 iso- and anteiso-BCFA similar to fluid milk. BCFA concentrations were 1.00 ± 0.64%, 1.63 ± 0.72% and 0.65 ± 0.07%, of total fatty acids in nātto, shrimp paste and fish sauce, respectively. In contrast, saturates, monounsaturates, and major polyunsaturates were more constant (coefficient of variation = 21%, 26% and 4% compared to 64% for nātto BCFA). Detection of fatty acid ethyl esters were confirmed in miso and found in homemade kimchi. Habitual nātto and/or fermented seafood consumption could support BCFA intakes similar to dairy consumption.

Sea Lions Develop Human-like Vernix Caseosa Delivering Branched Fats and Squalene to the GI Tract

Vernix caseosa, the white waxy coating found on newborn human skin, is thought to be a uniquely human substance. Its signature characteristic is exceptional richness in saturated branched chain fatty acids (BCFA) and squalene. Vernix particles sloughed from the skin suspended in amniotic fluid are swallowed by the human fetus, depositing BCFA/squalene throughout the gastrointestinal (GI) tract, thereby establishing a unique microbial niche that influences development of nascent microbiota. Here we show that late-term California sea lion (Zalophus californianus) fetuses have true vernix caseosa, delivering BCFA and squalene to the fetal GI tract thereby recapitulating the human fetal gut microbial niche. These are the first data demonstrating the production of true vernix caseosa in a species other than Homo sapiens. Its presence in a marine mammal supports the hypothesis of an aquatic habituation period in the evolution of modern humans.

Combined urea-thin layer chromatography and silver nitrate-thin layer chromatography for micro separation and determination of hard-to-detect branched chain fatty acids in natural lipids

A simple, fast and efficient procedure was developed for micro separation and enrichment of branched chain fatty acids (BCFA) from natural products using successive thin layer chromatography (TLC) technique coupling novel urea-TLC with AgNO3-TLC, which rely on the formation of urea adduction and AgNO3 bonding in methanol. These natural lipids contain a significant amount of straight chain fatty acids (FA). Fresh and fast urea-TLC and AgNO3-TLC plate making techniques were developed with more even coating and less coating material contamination before being utilized for separation. Goat milk fat was used as a model. Various experimental parameters that affect urea-TLC and AgNO3-TLC separation of BCFA were investigated and optimized, including coating of urea, concentration of original oil sample, mobile phase and sample application format. High efficiency of removal of straight chain FA was achieved with a low amount of sample in an easy and fast way. A total BCFA mix with much higher purity than previous studies was successfully achieved. The developed method has also been applied for the concentration and analysis of BCFA in cow milk fat and Anchovy oil.

anteiso-Fatty Acids in Brussels Sprouts (Brassica oleracea var. gemmifera L.): Quantities, Enantioselectivities, and Stable Carbon Isotope Ratios

anteiso-Fatty acids (aFAs) are a class of branched-chain fatty acids that are characterized by one methyl branch on the antepenultimate carbon of the straight acyl chain. aFAs are mainly produced by bacteria, and sources in vegetables are scarce. This study reports the concentrations of odd-numbered aFAs (a15:0-a21:0) in Brussels sprout buds. Selective enrichment followed by enantioselective gas chromatography with mass spectrometry in the selected ion monitoring mode revealed that both a15:0 and a17:0 were (S)-enantiopure in Brussels sprout samples. δ(13)C values (‰) of a17:0 in Brussels sprouts were comparable with those of palmitic acid, indicating no different source for both fatty acids.

High enantiomeric excess of the flavor relevant 4-alkyl-branched Fatty acids in milk fat and subcutaneous adipose tissue of sheep and goat

Volatile 4-alkyl-branched fatty acids are characteristic flavor compounds of sheep and goat. Due to the methyl branch, the carbon C-4 represents a stereogenic center with the possible presence of one or both enantiomers in the respective samples. In this study, we used enantioselective gas chromatography to study the enantiomeric composition of 4-methyloctanoic acid (4-Me-8:0) and 4-ethyloctanoic acid (4-Et-8:0) in milk and dairy products from sheep and goat as well as in goat subcutaneous tissue. Different columns coated with modified cyclodextrins were tested to resolve racemic 4-alkyl-branched fatty acid methyl ester standards. The best enantiomer resolution was obtained on 25% octakis(2,3,6-tri-O-ethyl)-γ-cyclodextrin (γ-TECD) diluted in OV-1701. For analysis of the food samples, the lipids were extracted and fatty acids in the extracts were converted into fatty acid methyl esters. Non-aqueous reversed-phase high-performance liquid chromatography was used to fractionate the samples in order to gain one solution enriched in 4-Me-8:0 methyl ester and one solution enriched with 4-Et-8:0 methyl ester. Subsequent analysis by enantioselective gas chromatography with mass spectrometry allowed only the detection of one enantiomer of 4-Me-8:0 and 4-Et-8:0 in the samples. By means of a non-racemic standard of 4-Me-8:0, it was found that the predominant enantiomer was (R)-4-Me-8:0.

Fatty acid composition of water buffalo meat

The fatty acid composition of intramuscular lipids of Longissimus dorsi (LD), Psoas major (PM), Biceps femoris (BF), Semitendinosus (ST) muscles and liver of water buffalo male calves was determined by capillary gas-liquid chromatography. The content of total lipids in the LD muscle was found to be maximum, followed by PM, BF and ST in decreasing order (1·03, 0·99, 0·66 and 0·55g/100g of fresh muscle). Liver contained 2·65 g of total lipids per 100 g of fresh tissue. Following the anatomical location, intramuscular lipids contained 44-55% of saturated fatty acids, of which the major components were stearic and palmitic acids. Mono-unsaturated fatty acids (31-40%) composed mainly oleic acid (90%). The PUFA contents in PM, LD, ST and BF were, respectively, 11%, 12%, 13% and 16%. The predominant PUFA were linoleic (66%) and arachidonic (25%). The significance of difference of PUFA content between muscles is discussed. Liver contained 48%, 27% and 22% saturated, monosaturated and PUFA, respectively. The PUFA in liver were linoleic (36%), C20 (47%) and C22 (9%).

Branched chain fatty acid content of United States retail cow's milk and implications for dietary intake

Branched chain fatty acids (BCFA) have recently been shown to be a major component of the normal human newborn gastrointestinal tract and have long been known to be a component of human milk. Ruminant food products are major sources of fat in the American diet, but there are no studies of milkfat BCFA content in retail milk. We report here the profile and concentrations of BCFA in a representative sampling of retail milk in the 48 contiguous United States (US), and their estimated intake in the American diet. Conventionally produced whole fluid milk samples were obtained from 56 processing plants across the contiguous 48 states. Retail milk samples contain exclusively iso- and anteiso-BCFA with 14-18 carbons. BCFA were 2.05 ± 0.14%, w/w of milkfat fatty acids (mean ± SD), and anteiso-BCFA comprised more than half this total. Based on these data and USDA food availability data, the average per capita BCFA intake of Americans is estimated to be about 220 mg/d from dairy; if current dietary recommendations were followed, BCFA intake would be about 400 mg/d. Adding intake from beef consumption, these estimates rise to approximately 400 and 575 mg/d, respectively. These results indicate that BCFA intake is a substantial fraction of daily fat intake, in amounts exceeding those of many bioactive fatty acids.

Stable carbon isotope ratios of methyl-branched fatty acids are different to those of straight-chain fatty acids in dairy products

Methyl-branched fatty acids (MBFAs) are the dominant form of fatty acid found in many bacteria. They are also found at low levels in a range of foodstuffs, where their presence has been linked to bacterial sources. In this study we evaluated the potential of compound-specific isotope analysis to obtain insights into the stable carbon isotope ratios (delta(13)C values in per thousand) of individual MBFAs and to compare them to the stable carbon isotope ratios of straight-chain fatty acids in food. Due to their low abundance in foodstuffs, the MBFAs were enriched prior to gas chromatography coupled to isotope ratio mass spectrometric (GC-IRMS) analysis. After transesterification, urea complexation was used to suppress the 16:0 and 18:0 methyl esters that were dominant in the samples. Following that, silver-ion high performance liquid chromatography was used to separate the saturated from the unsaturated fatty acids. The resulting solutions of saturated fatty acids obtained from suet, goat's milk, butter, and human milk were studied by GC-IRMS. The delta(13)C values of fatty acids with 12-17 carbons ranged from -25.4 per thousand to -37.6 per thousand. In all samples, MBFAs were most depleted in carbon-13, followed by the odd-chain fatty acids 15:0 and 17:0. 14:0 and 16:0 contained the highest proportions of carbon-13. The results from this study illustrate that MBFAs have distinctive delta(13)C values and must originate from other sources and/or from very different substrates. These measurements support the initial hypothesis that delta(13)C values can be used to attribute MBFAs to particular sources.

The composition of bovine milk lipids: January 1995 to December 2000

Data from recent publications on bovine milk lipids are presented and discussed. This includes extraction of lipids, triacylglycerols, phospholipids, other complex lipids, sterols, isoflavones, and fatty acids. Improved gas-liquid and high performance liquid chromatography were used. Data on the trans and cis isomers of fatty acid and of conjugated linoleic acids are given, and the analyses are described. Papers about the lipids in milks and dairy products from the United States are few; where with the exception of trans-fatty acid isomers and conjugated linoleic acids, almost no research has been reported.

Bovine milk gangliosides: changes in ceramide moiety with stage of lactation

The stage of lactation is one of the most important factors that influence milk composition. Changes in fatty acids from triacylglycerols and phospholipids have already been reported. In this study, we looked for a lactational change in the ganglioside lipid moiety since ganglioside contents and patterns vary strongly with stage of lactation. Individual gangliosides from four stages were isolated, methanolized to cleave the bonds between individual constituents, and derivatized for gas-liquid chromatography and gas chromatography/mass spectrometry analyses. Ceramide components, both fatty acids (as methyl esters derivatives) and long-chain bases, were identified and quantified. The results pointed to a marked change in ceramide from colostrum to milk that was characterized by a dramatic decrease in saturated and the longest-chain fatty acids as well as an increase in 18:1 and 18:2. The major long-chain base along lactation was a recently described structure, 3-ethoxy-15:0 sphinganine. Other new long-chain base structures appeared in these gangliosides. All these changes suggest differences in the fluidity of the fat globule membrane, reflecting physiological variations in cows with respect to milk production.

Fatty acid composition of caprine milk: major, branched-chain, and trans fatty acids

The fatty acid composition of caprine milk fat was studied using capillary gas chromatography. Milk was obtained from five goat herds belonging to different breeders in the Murcia region (Spain) and collected monthly (from November to May). The results showed significant differences among herds mainly in long-chain fatty acids (C16:0, C18:0, and C18:2). There were five branched-chain fatty acids (iso- and anteiso-C15:0, iso- and anteiso-C17:0, and iso-C16:0) with > 0.1% of the total fatty acid methyl esters and another 31 (the most monomethylated) with < 0.1%, including 4-ethyloctanoate, which is implicated in goat-like flavors. To study the content of trans unsaturated fatty acids, the fatty acid methyl esters were previously fractionated by AgNO3-thin layer chromatography. The mean contents of trans-C16:1 and trans-C18:1 were 0.16 and 2.12%, respectively. The distribution profile of trans-C18:1 was also studied.

Antimutagenicity of yogurt

Yogurt is milk fermented by a mixture of two bacteria: Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus salivarius ssp. thermophilus. Epidemiological studies have correlated a reduced risk of colon cancer with yogurt consumption. Independent studies have established that yogurt and extracts thereof are antimutagenic. Although multiple explanations can account for yogurt's putative anticarcinogenicity, we are interested in testing the hypothesis that antimutagenic compounds produced during fermentation are responsible. We recently reported on the antimutagenicity of an acetone extract of yogurt against the experimental carcinogens N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and 3.2'dimethyl-4-aminobiphenyl (DMAB) (Mutation Res. (1995) 334, 213-224). We are now aware that palmitic acid is an active ingredient against MNNG.

Composition of molecular species of triacylglycerols in bovine milk fat

Triacylglycerols from bovine milk fat were fractionated by reversed-phase liquid chromatography. The fatty acid and triacylglycerol compositions of each fraction were determined by capillary gas chromatography. These data were used to determine the accurate proportions of 223 individual molecular species of even-numbered triacylglycerols, accounting for 80% of total triacylglycerols (all percentages are expressed as moles per 100 mol). The three major triacylglycerols were butyroylpalmitoylacylglycerols, namely butyroylpalmitoyloleoylglycerol (4.2%), butyroyldipalmitoylglycerol (3.2%), and butyroylmyristoylpalmitoylglycerol (3.1%). Twenty-two triacylglycerols (> 1%) contained at least two of the four major long-chain fatty acids (C14:0, C16:0, C18:0, and C18:1). Among them were eight butyroyldiacylglycerols, the proportions of which reached 19% in total but only 12% when calculated on the basis of a random distribution of the fatty acids in the triacylglycerol molecules. More generally, most of the triacylglycerols that are composed of a short-chain fatty acid (C4:0 or C6:0) and two fatty acids in the range of C12 to C18 are preferentially synthesized by the mammary gland; their proportions (36% in total) were higher than the corresponding random values (24% in total). Conversely, the total amounts of simple (.4%) and mixed (2.9%) saturated long-chain (C14:0 to C18:0) triacylglycerols were much lower than those expected from random calculation (1.9 and 6.1%, respectively).

Low molecular weight branched-chain and n-chain fatty acids in caprine and bovine colostrum

Colostrum from French-Alpine and Anglo-Nubian goats and Holstein cows was collected and analyzed for both total and FFA of 12 and fewer carbon atoms. Short-chain VFA were separated from long-chain fatty acids using simultaneous distillation extraction. The n-butyl esters of fatty acids were quantified by gas chromatography, and their identity was confirmed by gas chromatography-mass spectrometry. The concentration of decanoic acid was 33 and 83% less in Holstein colostrum than in colostrum from Alpine and Nubian goats, respectively. Colostrum from Nubian goats had twice as much decanoic acid as colostrum from Alpine goats. The FFA in colostrum that differed between species but not between goat breeds were octanoic and decanoic acids. These respective fatty acids were approximately two and three times greater in colostrum from goats than in colostrum from Holsteins. The quantity of decanoic acid was different between goat breeds and between animal species. The ratio of total fatty acid concentration to free-state concentration for hexanoic acid appeared to be useful for differentiating between Nubian and Alpine goat colostrum as well as between Nubian and Holstein colostrums.

Determination of bovine butterfat triacylglycerols by reversed-phase liquid chromatography and gas chromatography

Triacylglycerols (TGs) from a sample of summer butterfat (bovine milk) were analysed and fractionated by reversed-phase liquid chromatography (RPLC). Fatty acid and TG composition of eac of the 47 RPLC fractions ranging from 0.1 to 6.9% were determined by capillary gas chromatography. The data were used together to determine the quantitative composition of the molecular species of TGs. A large number of TG species, accounting for 80% of the total, could be unequivocally identified and individually determined. The combination of the chromatographic methods used proved to be a powerful and accurate approach for the determination of molecular species of TGs in a complex fat, but also a difficult and time-consuming task.

Metabolism of leucine by the isolated perfused goat udder

Seven lactating goat mammary glands from 6 goats were perfused for several hours in the presence of [U-14C]L-leucine (4 experiments) or [2-3H; 1-14C]DL-leucine (3 experiments) and received adequate quantities of glucose, acetate and amino acids. Radioactivity in casein was mainly recovered in leucine and 90% of casein leucine was derived from free plasma leucine. About 64% of the leucine molecules were used for casein synthesis. Up to 12% of the molecules were channelled into lipid synthesis, while the remaining (up to 24%) were metabolized to CO2. From the 3H/14C ratio of casein and casein leucine, it was calculated that 70-80% of the leucine molecules were reversibly transaminated before their incorporation into milk protein. However, only 4-8% of the plasma leucine molecules were transaminated during passage through the udder. Different pools for oxidation and for protein synthesis may be present in the goat mammary gland.

Propionate for fatty acid synthesis by the mammary gland of the lactating goat

Isolated mammary glands of lactating goats were perfused with heparinized and oxygenated blood for 8 to 15 h. Adequate quantities of glucose, acetate, and amino acid were added to the perfusate. After addition of propionate to the perfusion blood, concentrations of odd-numbered and of monomethyl-substituted fatty acids other than those with iso and anteiso configuration increased in the milk fat. These acids seem to be synthesized de novo in the mammary gland. The increase of C17:0 concentration was weak and problematic. We suggest that propionate is acting as a precursor for monomethyl-substituted fatty acids by way of methylmalonyl-CoA. The activating effect of propionate administration upon milk fatty acid production was largest for odd-numbered followed by monomethyl-substituted fatty acids. No increase of iso acids was observed in milk fat in the propionate-infused glands whereas the increase of anteiso acids was extremely small. This agrees with the conception that iso and anteiso fatty acids are synthesized by rumen bacteria.