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Cyclopropane fatty acids (CPFAs), such as dihydrosterculic acid (DHSA), are secondary fatty acids of microbial origin recently identified in foods and human plasma. Their plasmatic concentration is suggested to be affected by consumption of CPFA-rich foods, especially dairy products. However, very little is known about the occurrence of CPFAs in human tissues and their nutritional value. This preliminary screening aims to investigate the presence of CPFAs in breastmilk obtained from lactating Spanish women following a free-living diet by performing the GC–MS method previously applied for CPFA determination in dairy products. For the first time, DHSA was detected in human breast milk fat (at about 0.4 mg/ 100 mL breastmilk), supporting the importance of better understanding its occurrence in vivo that may be related to the dietary habits followed by the lactating mother. Future studies are needed to determine its biological role both in adults and infants, who would be exposed to this CPFA during the breastfeeding., Pilar Gómez-Cortés gratefully acknowledges the Spanish Ministry of Science and Innovation for the Ramón y Cajal research contract (RYC2019-027933-I).

Angiopoietin-like proteins (ANGPTL) 3, -4 and -8 regulate lipid metabolism by altering lipoprotein lipase activity, but it is not known how cottonseed oil (CSO) differentially affects postprandial responses of ANGPTL’s in humans. We compared the effect of a diet rich in either CSO or olive oil (OO) on fasting and postprandial ANGPTL’s. Fifteen males completed two feeding trials in random order: 1) a CSO-rich diet and 2) an OO-rich diet with fasting and postprandial blood samples collected pre-diet at visit 1 (v1) followed by a 5-day feeding trial and a post-diet visit (v2) identical to v1 and a 2–4-week washout period. Fasting ANGPTL4 and ANGPTL8 decreased from v1 to v2 after the CSO diet and increased with the OO diet. Postprandial ANGPTL3, -4, and -8 were lower following the CSO meal. The lipid-lowering effects of CSO may be mediated by reduced fasting and postprandial ANGPTL3, -4 and -8 responses.

Cotton GHB811 was developed to confer tolerance to glyphosate and HPPD inhibitor herbicides. The molecular characterisation data and bioinformatic analyses do not identify issues requiring food/feed safety assessment. None of the identified differences in the agronomic/phenotypic and compositional characteristics tested between cotton GHB811 and its conventional counterpart needs further assessment, except for % lint, lint length and dihydrosterculic acid, which do not raise nutritional and safety concerns. The GMO Panel does not identify safety concerns regarding the toxicity and allergenicity of the 2mEPSPS and HPPD W336 proteins as expressed in cotton GHB811 and finds no evidence that the genetic modification would change the overall allergenicity of cotton GHB811. In the context of this application, the consumption of food and feed from cotton GHB811 does not represent a nutritional concern in humans and animals. The GMO Panel concludes that cotton GHB811 is as safe as the conventional counterpart and non-GM cotton reference varieties tested, and no post-market monitoring of food/feed is considered necessary. In the case of accidental release of viable cotton GHB811 seeds into the environment, this would not raise environmental safety concerns. The post-market environmental monitoring plan and reporting intervals are in line with the intended uses of cotton GHB811. The GMO Panel concludes that cotton GHB811 is as safe as its conventional counterpart and the tested non-GM cotton reference varieties with respect to potential effects on human and animal health and the environment., European Commission. EFSA-Q-2018-00808

This work describes the discovery, biosynthesis, and chemical synthesis of a previously unknown class of lipids, trehalose phospholipids, in pathogenic Salmonella species. Trehalose phospholipids stimulate the innate immune receptor Mincle, the receptor for the strong adjuvant mycobacterial cord factor., Salmonella species are among the world’s most prevalent pathogens. Because the cell wall interfaces with the host, we designed a lipidomics approach to reveal pathogen-specific cell wall compounds. Among the molecules differentially expressed between Salmonella Paratyphi and S. Typhi, we focused on lipids that are enriched in S. Typhi, because it causes typhoid fever. We discovered a previously unknown family of trehalose phospholipids, 6,6′-diphosphatidyltrehalose (diPT) and 6-phosphatidyltrehalose (PT). Cardiolipin synthase B (ClsB) is essential for PT and diPT but not for cardiolipin biosynthesis. Chemotyping outperformed clsB homology analysis in evaluating synthesis of diPT. DiPT is restricted to a subset of Gram-negative bacteria: large amounts are produced by S. Typhi, lower amounts by other pathogens, and variable amounts by Escherichia coli strains. DiPT activates Mincle, a macrophage activating receptor that also recognizes mycobacterial cord factor (6,6′-trehalose dimycolate). Thus, Gram-negative bacteria show convergent function with mycobacteria. Overall, we discovered a previously unknown immunostimulant that is selectively expressed among medically important bacterial species.

A survey was conducted to determine the content of cyclopropane fatty acids (CPFAs) and &omega, cyclohexyl fatty acids (CHFAs) by using gas chromatography- mass spectrometry (GC-MS) and proton nuclear magnetic resonance (1H NMR) techniques in various meat samples from different species, including commercial samples and complex and thermally processed products (i.e., Bolognese sauce). The CPFAs concentration (as the sum of two isomers, namely dihydrosterculic acid and lactobacillic acid) in bovine meat fat (ranging between 70 and 465 mg/kg fat) was positively related to a silage-based diet, and therefore, they are potential biomarkers for monitoring the feeding system of cattle. CHFAs, such as 11-cyclohexylundecanoic and 13-cyclohexyltridecanoic acids, were only found in lipid profiles from ruminant species, and a linear trend was observed in their content, together with iso-branched fatty acids (iso-BCFAs) deriving from ruminal fermentation, as a function of bovine meat percentage in both raw and cooked minced meat. Thus, CHFAs are potential biomarkers for the assurance of the meat species and, combined with iso-BCFAs, of the beef/pork ratio even in complex meat matrices. The proposed approaches are valuable novel tools for meat authentication, which is pivotal in the management of meat quality, safety, and traceability.

Cyclopropane fatty acids (CPFAs) are an investigated class of secondary fatty acids of microbial origin recently identified in foods. Even though the dietary daily intake of this class of compounds it has been recently estimated as not negligible, to date, no studies specifically have investigated their presence in human plasma after consumption of CPFA-rich sources. Therefore, the aims of this study were (i) to test CPFAs concentration in human plasma, thus demonstrating their in vivo bioaccessibility and potential bioavailability, (ii) to investigate a dose-response relationship between medium term chronic intake of CPFAs-rich foods and both CPFAs and plasma total fatty acid profiles in healthy subjects. Ten healthy normal weight adults were enrolled for conducting an in vivo study. Participants were asked to follow a CPFA-controlled diet for 3 weeks, consuming 50 g of Grana Padano cheese (GP) and 250 mL of whole cow milk, which correspond to a total of 22.1 mg of CPFAs. Fasting CPFAs concentration were monitored for eight timepoints during the whole study and plasma total fatty acids composition was determined by GC-MS. CPFAs, mainly dihydrosterculic acid (DHSA), were identified in plasma total fatty acids profile at the beginning of the study and after dietary treatment. A significant (p &lt, 0.05) increase of CPFAs mean plasma concentration (n = 10) were observed at the end of the dietary intervention. Contrarily, the total fatty acids composition of the general plasma fatty acids profile did not significantly change (p &ge, 0.05) during the dietary intervention period. This is the first investigation demonstrating that CPFAs are bioaccessible in vivo and, as expected, their plasmatic concentration may be affected by consumption of CPFAs-rich foods. This research will open the door to further detailed research, which may better elucidate the role of these compounds in human health.

Saturated mid-chain branched fatty acids (SMCBFAs) are widely used in the petrochemical industry for their high oxidative stability and low melting temperature. Dihydrosterculic acid (DHSA) is a cyclopropane fatty acid (CPA) that can be converted to SMCBFA via hydrogenation, and therefore oils rich in DHSA are a potential feedstock for SMCBFA. Recent attempts to produce DHSA in seed oil by recombinant expression of cyclopropane fatty acid synthases (CPFASes) resulted in decreased oil content and poor germination or low DHSA accumulation. Here we explored the potential for plant vegetative tissue to produce DHSA by transiently expressing CPFAS enzymes in leaf. When CPFASes from plant and bacterial origin were transiently expressed in Nicotiana benthamiana leaf, it accumulated up to 1 and 3.7% DHSA in total fatty acid methyl ester (FAME), respectively, which increased up to 4.8 and 11.8%, respectively, when the N. benthamiana endogenous oleoyl desaturase was silenced using RNA interference (RNAi). Bacterial CPFAS expression produced a novel fatty acid with a cyclopropane ring and two carbon-carbon double bonds, which was not seen with plant CPFAS expression. We also observed a small but significant additive effect on DHSA accumulation when both plant and bacterial CPFASes were co-expressed, possibly due to activity upon different oleoyl substrates within the plant cell. Lipidomics analyses found that CPFAS expression increased triacylglycerol (TAG) accumulation relative to controls and that DHSA was distributed across a range of lipid species, including diacylglycerol and galactolipids. DHSA and the novel CPA were present in phosphatidylethanolamine when bacterial CPFAS was expressed in leaf. Finally, when plant diacylglycerol acyltransferase was coexpressed with the CPFASes DHSA accumulated up to 15% in TAG. This study shows that leaves can readily produce and accumulate DHSA in leaf oil. Our findings are discussed in line with current knowledge in leaf oil production for a possible route to DHSA production in vegetative tissue.

A survey was carried out to determine the presence of cyclopropane fatty acids (CPFA) in various dairy products. CPFA such as lactobacillic acid and dihydrosterculic acid are components of bacterial membranes and have been recently detected in milk from cows fed with maize silage. In this paper about 200 dairy samples comprising cow, sheep, and goat milk, cheese, yogurt/fermented milk, and butter were analyzed. Results showed that cow milks were generally positive to CPFA (0.014-0.105% of total fatty acids), while goat, yak, and sheep milks were negative. Experimental yogurt and fermented milks showed the same CPFA content of the starting milk. Positive to CPFA were also the majority of samples of commercial butter and cheeses, except some PDO cheeses as Parmigiano-Reggiano and Fontina, cheeses from mountain regions, and goat and sheep cheeses. These data suggest that the presence of CPFA in dairy products could be used as a marker of silage feeding.

(9 R ,10 S )-Dihydrosterculic acid has been prepared from ( S S , S S )-1,1-bis( p -tolylsulfinyl)methane in a sequence involving an asymmetric Corey–Chaykovsky cyclopropanation and two sulfoxide/lithium exchange reactions. In most steps, the reaction conditions had to be optimized for the unbranched alkyl substituents, which were prone to Evans–Mislow rearrangements and subsequent degradation.

Cyclopropane fatty acids (CPFA), as lactobacillic acid and dihydrosterculic acid, are components of bacterial membranes and have been recently detected in milk and in dairy products from cows fed with corn silage. In this paper, a specific quantitative gas chromatography-mass spectrometry (GC-MS) method for the detection of CPFA in cheeses was developed, and the quality parameters of the method (limit of detection, limit of quantitation, and intralaboratory precision) were assessed. Limit of detection and quantitation of CPFA were, respectively, 60 and 200 mg/kg of cheese fat, and the intralaboratory precision, determined on three concentration levels, satisfied the Horwitz equation. This method was applied to 304 samples of PDO cheeses of certified origin, including Parmigiano Reggiano (Italy), Grana Padano (Italy), Fontina (Italy), Comte (France), and Gruyere (Switzerland). Results showed that CPFA were absent in all of the cheeses whose Production Specification Rules expressly forbid the use of silages (Parmigiano Reggiano, Fontina, Comte, and Gruyere). CPFA were instead present in variable concentrations (300-830 mg/kg of fat) in all of the samples of Grana Padano cheese (silages admitted). A mix of grated Parmigiano Reggiano and Grana Padano was also prepared, showing that the method is able to detect the counterfeiting of Parmigiano Reggiano with other cheeses up to 10-20% Grana Padano content. These results support the hypothesis that CPFA can be used as a marker of silage feedings for cheeses, and the data reported can be considered a first attempt to create a database for CPFA presence in PDO cheeses.

Semisynthetic cyclopropanoic fatty acids (CPFA), cis-9,10-methyleneheradecanoic acid, cis-7,8-methylenehexadecanoic acid, and dihydrosterculic acid, were obtained from the corresponding olefinic acids. Their chromatographic equivalent chain lengths on two liquid phases, together with the mass spectral data of the methoxy derivatives, were compared to the CPFA methoxy derivatives isolated from the lipid content of litchi seeds. The fatty acid composition of the litchi seed lipids included palmitic acid, oleic acid, linoleic acid, and CPFA

The percentage contents of oil and protein in the seeds of 17 species belonging to 9 genera of the Sterculiaceae family, growing in Madagascar, were determined. The major fatty acids were palmitic (11.6-27.5%), oleic (8.3-32.6%), linoleic (4.2-45.8% ), malvalic (tr-53.7961, and sterculic (1.3-24.876) acids. Heritiera littoralis seed oil was characterized by a high content of malvalic (53.7 %) and sterculic acids (12.4 % ). Cyclopropene fatty acids were identified and determined by using a combination of gas chromatographic and 'H and 13C NMR analyses. Dihydrosterculic acid was also detected in all samples at a low concentration.

The proportions of the cyclopropenoid fatty acids (CPA) esters, malvalate and sterculate, varied little in lipids from individual cottonseeds. Coefficients of variation were 10% and 20% for seeds from a lock and 13 varieities, respectively. Within the seed, variations in CPA concentrations were very large. Cyclopropenoid fatty acid concentration in the lipids decreased from 28% in the root tip to 2% in the top of the axis, and to 0.02% in the portion of the cotyledons nearest to the hull. The axial portion was only ca. 5% of the kernel, yet it contained 75% of the CPA. Distribution of dihydrosterculic acid, the precursor of CPA, was similar to that of CPA. High concentrations of CPA were found in immature seeds, root tip and radicle of germinated seeds, and root tips of cotton plants.

The aril and seeds of the fruit Durian (Durio zibethinus, Murr.) were examined for their protein content and fatty acid composition by gas liquid chromatography (GLC). The values (area percentage) for fatty acids as methyl esters were: aril=14∶0 (0.91%); 16∶0 (34.13%); 16∶1 (7.10%); 18∶0 (1.21%); 18∶1 (42.14%); 18∶2 (7.85%) and 18∶3 plus 20∶0 (5.69%), Seeds=14∶0 (0.12%); 16∶0 (12.20%); 16∶1 (1.15%); 18∶0 (1.42%); 18∶1 (8.42%); 18∶2 (6.50%); dihydrosterculic acid (2.52%); 18∶3 plus 20∶0 (11.30%); malvalic acid (15.72%); sterculic acid (38.53%) and 22∶0 (1.21%). The germ oil contained the highest amount of sterculic acid. The cooking temperatures employed reduced the malvalic and sterculic acid contents in seeds only by ca. 22% and 19%, respectively.

Analysis of Hibiscus sabdariffa seed oil from different seed collections (or cultivars), representing different growing areas, showed differences in the fatty acid pattern, especially with respect to linoleic (30.1-37.45%) and epoxyoleic (trace to 5.3%). The results showed different values from those previously reported for the cyclopropenoid fatty acid, found to be malvalic acid (0.4-2.0%), responsible for the positive Halphen response of the oil. It is now also established that the oil contains dihydrosterculic acid (1.0-1.6%) which has been reported previously in other species of the genus Hibiscus. The results of the rest of fatty acids showed ranges for myristic 0.2-0.5%, palmitic 17.4-22.6%, stearic 3.9-5.2% and oleic acid 34.6-39.8%.

Lipids were extracted with chloroform-methanol from Ceiba pentandra seeds at different stages of maturity, separated by TLC and tested for the Halphen response. Cyclopropene fatty acids (CFA) were absent from mono- and diglycerides and phospholipids. Free fatty acids, diglycerides and phospholipids were maximum on the 23rd, 65th and 65th day respectively and minimum on the 96th day (mature) after flowering. The fatty acid compositions were determined by GLC. Dihydromalvalic acid reached a maximum value on the 81st day, while malvalic acid remained almost constant from the 38th day and sterculic acid steadily increased. Dihydrosterculic acid was noticed only in the free fatty acids and phospholipids. The positional distribution in the triglycerides was determined by lipolysis. Since CFA inhibited lipolysis partially the triglycerides were dissolved in chloroform and treated with methanolic silver nitrate prior to lipolysis. CFA were found in the 2-position, though to a lesser extent than in the primary positions, indicating rearrangement of glycerides during maturation.

Evidence is provided that sterculic and malvalic acids occur together in seed oils ofSterculia foetida, Hibiscus syriacus, andLavatera trimestris. Sterculia foetida oil contains 54.5% sterculic and 6.7% malvalic acids;Hibiscus syriacus oil contains 16.3% malvalic and 3.4% sterculic; andLavatera trimestris oil contains 7.7% malvalic and 0.6% sterculic acids.Hibiscus syriacus oil also contains 1.5% dihydrosterculic acid. The cyclopropenoid acids were characterized by hydrogenation in conjunction with gas-liquid chromatography and by oxidation to β-dioxo acids with subsequent cleavage with peracetic acid. Acetolysis of epoxides in the presence of cyclopropenes was effected by room temperature treatment with acetic acid-10% sulfuric acid (5∶2).

The total fatty acids isolated from the phospholipids of Salmonella typhimurium contained C 17 (16%) and C 19 (4%) components which were identified by gas chromatography as fatty acids with a cyclopropane-ring structure. The C 19 component was a mixture of cis -9,10-methylene octadecanoic acid (dihydrosterculic acid) and cis -11,12-methylene octadecanoic acid (lactobacillic acid). The lactobacillic acid accounted for approx. 80% of the C 19 acids.

10-Thiastearic acid is a specific inhibitor of the biosynthesis of dihydrosterculic acid (9,10-methyleneoctadecanoic acid) in the trypanosomatid protozoan Crithidia fasciculata. A 50% inhibition of the biosynthesis of dihydrosterculate is observed in the presence of 4 microM 10-thiastearate in the protozoan growth medium, but little effect is seen on the distribution of the other fatty acids. In addition, the growth of the protozoa is slowed by the presence of 10-thiastearate, with 50% growth inhibition produced at about 10 microM. A possible mechanism of this inhibition and the implication of this result with regard to the design of antiprotozoal agents are discussed.

The seed oil ofEuphoria longana, Sapindaceae, contains 17.4% of 9,10-methyleneoctadecanoic (dihydrosterculic) acid. This identification is based on information from thin layer chromatography, infrared analysis, gas liquid chromatography, nuclear magnetic resonance and mass spectroscopy. Since GLC of the oil showed components that emerged between the usual triglycerides, the cyclopropanoid acid is apparently a triglyceride constituent. The presence of smaller amounts, less than 1%, of cyclopropanoid fatty acids of different chain lengths is indicated by GLC and TLC analyses of the methyl esters. The other major fatty acids in this oil are: 16∶0 (19%), 18∶0 (7%), 18∶1 (36%), 18∶2 (6%), 18∶3 (5%) and 20∶0 (4%).Euphoria oil contains considerably larger amounts of cyclopropanoid fatty acids than previously reported in other seed oils.

Hay milk is a traditional dairy product recently launched on the market. It is protected as “traditional specialty guaranteed” (TSG) and subjected to strict regulations. One of the most important restrictions is that the cow’s feed ration must be free from silage. There is the need for analytical methods that can discriminate milk obtained from a feeding regime including silage. This study proposes two analytical approaches to assess the authenticity of hay milk. Hay milk and milk from cows fed either with maize or grass silage were analyzed by targeted GC-MS for cyclopropane fatty acid (dihydrosterculic acid, DHSA) detection, since this fatty acid is strictly related to the bacterial strains found in silage, and by HPLC-HRMS. The presence of DHSA was correlated to the presence of maize silage in the feed, whereas it was ambiguous with grass silage. HPLC-HRMS analysis resulted in the identification of 14 triacylglycerol biomarkers in milk. With the use of these biomarkers and multivariate statistical analysis, we were able to predict the use of maize and grass silage in the cow’s diet with 100% recognition. Our findings suggest that the use of analytical approaches based on HRMS is a viable authentication method for hay milk.

The aerial parts of BLUMEA AMPLECTENS var. ARENARIA afforded taraxasteryl acetate, dihydrosterculic acid, the sesquiterpene ferutinin, and the acetylenic thiophene diol, 3,4-dihydroxy-8-[5'-methylthiophen-2'-yl]-1, 5-octadien-7-yne, named as amplectol. Thestructures were elucidated by spectroscopic methods. A biogenetic pathway for the formation of amplectol in the plant is also suggested.

Lychee seed oil (Litchi sinensis, Fam. Sapindaceae) contains 41% of dihydrosterculic acid (cis-9,10-methyleneoctadecanoic acid), and 8% of cis-9,10-methylenehexadecanoic acid, the highest concentration of cyclopropanoid acids ever recorded in a seed oil.