Monoacylglycerol Form of Omega-3s Improves Its Bioavailability in Humans Compared to Other Forms.

Numerous benefits are attributed to omega-3 fatty acids (OM3) especially in cardiovascular health. However, bioavailability and clinical efficacy depend on numerous factors, including OM3 form, food matrix effects (especially the lipid content of the diet), and metabolic capacity. Here, we show in humans that a "pre-digested" OM3-sn-1(3)-monoacylglycerol lipid structure (OM3-MAG) has a significantly greater absorption at high therapeutic doses (2.9 g/day) than the most commonly OM3-ethyl ester (3.1 g/day) form (used for the treatment of hypertriglyceridemia), and a comparable profile to other pre-digested OM3 free fatty acids (OM3-FFA) structure (3.2 g/day). Nutritional supplement doses of MAG resulted in similar increases in OM3 blood level, compared to OM3 triacylglycerols (OM3-TAG) supplements in obese subjects (1.2 g/day) under low fat diet, and in children with cystic fibrosis (1.0 g/day). These results suggest that both forms of pre-digested OM3-MAG and OM3-FFA are effectively absorbed and re-incorporated effectively into triacylglycerols inside the enterocytes, before being exported into the chylomicrons lipid transport system. The pre-digested OM3-MAG might provide a more effective therapy in severe cardiovascular conditions where high doses of OM3 are required and a low-fat diet is indicated, which limited digestive lipase activity.

Effects of dietary glycerol monolaurate on productive performance, egg quality, serum biochemical indices, and intestinal morphology of laying hens.

Glycerol monolaurate (GML) has been widely used as an effective antibacterial emulsifier in the food industry. A total of 360 44-week-old Hy-Line brown laying hens were randomly distributed into four groups each with six replicates of 15 birds, and fed with corn-soybean-meal-based diets supplemented with 0, 0.15, 0.30, and 0.45 g/kg GML, respectively. Our results showed that 0.15, 0.30, and 0.45 g/kg GML treatments significantly decreased feed conversion ratios (FCRs) by 2.65%, 7.08%, and 3.54%, respectively, and significantly increased the laying rates and average egg weights. For egg quality, GML drastically increased albumen height and Haugh units, and enhanced yolk color. Notably, GML increased the concentrations of polyunsaturated and monounsaturated fatty acids and reduced the concentration of total saturated fatty acids in the yolk. The albumen composition was also significantly modified, with an increase of 1.02% in total protein content, and increased contents of His (4.55%) and Glu (2.02%) under the 0.30 g/kg GML treatment. Additionally, GML treatments had positive effects on the lipid metabolism of laying hens, including lowering the serum triglyceride and total cholesterol levels and reducing fat deposition in abdominal adipose tissue. Intestinal morphology was also improved by GML treatment, with increased villus length and villus height to crypt depth ratio. Our data demonstrated that GML supplementation of laying hens could have beneficial effects on both their productivity and physiological properties, which indicates the potential application of GML as a functional feed additive and gives us a new insight into this traditional food additive.

Glycerol-Monolaurate-Mediated Attenuation of Metabolic Syndrome is Associated with the Modulation of Gut Microbiota in High-Fat-Diet-Fed Mice.

SCOPE: The gut microbiota plays an important role in the development of diet-induced obesity and metabolic syndrome. Glycerol monolaurate (GML), a widely consumed food emulsifier, is reported to promote metabolic disorder and gut microbiota dysbiosis in low-dose supplementation upon low-fat-diet feeding. However, little is known about whether GML produce the same effects in mice fed a high-fat diet (HFD). METHODS AND RESULTS: C57BL/6 mice are fed a HFD with or without GML supplementation (150, 300, and 450 mg kg-1 ) for 10 weeks. The results demonstrated that higher GML treatment (450 mg kg-1 ) ameliorates HFD-induced metabolic disorders, supported by prevented visceral fat deposition, improved hyperlipidemia, modulated hepatic lipid metabolism, and reduced serum proinflammatory cytokine, TNF-α. Additionally, all doses of GML attenuated circulating lipopolysaccharide load and insulin resistance. Notably, GML ameliorates HFD-induced gut microbiota dysbiosis, with increases in Bacteroides uniformis, Akkermansia, Bifidobacterium, and Lactobacillus and decreases in Escherichia coli, Lactococcus, and Flexispira. Spearman's correlation analysis indicates that these enriched specific genera are significantly associated with the metabolic improvements of GML. CONCLUSION: The findings identify the links between gut microbiota and GML-induced metabolic improvements, suggesting that the attenuation of HFD-induced metabolic disorders by higher GML supplementation may occur through targeting gut microbiota.

Effects of dietary glycerol monolaurate on productive performance, egg quality, serum biochemical indices, and intestinal morphology of laying hens / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Glycerol monolaurate (GML) has been widely used as an effective antibacterial emulsifier in the food industry. A total of 360 44-week-old Hy-Line brown laying hens were randomly distributed into four groups each with six replicates of 15 birds, and fed with corn-soybean-meal-based diets supplemented with 0, 0.15, 0.30, and 0.45 g/kg GML, respectively. Our results showed that 0.15, 0.30, and 0.45 g/kg GML treatments significantly decreased feed conversion ratios (FCRs) by 2.65%, 7.08%, and 3.54%, respectively, and significantly increased the laying rates and average egg weights. For egg quality, GML drastically increased albumen height and Haugh units, and enhanced yolk color. Notably, GML increased the concentrations of polyunsaturated and monounsaturated fatty acids and reduced the concentration of total saturated fatty acids in the yolk. The albumen composition was also significantly modified, with an increase of 1.02% in total protein content, and increased contents of His (4.55%) and Glu (2.02%) under the 0.30 g/kg GML treatment. Additionally, GML treatments had positive effects on the lipid metabolism of laying hens, including lowering the serum triglyceride and total cholesterol levels and reducing fat deposition in abdominal adipose tissue. Intestinal morphology was also improved by GML treatment, with increased villus length and villus height to crypt depth ratio. Our data demonstrated that GML supplementation of laying hens could have beneficial effects on both their productivity and physiological properties, which indicates the potential application of GML as a functional feed additive and gives us a new insight into this traditional food additive.

Comparison of the Incorporation of DHA in Circulatory and Neural Tissue When Provided as Triacylglycerol (TAG), Monoacylglycerol (MAG) or Phospholipids (PL) Provides New Insight into Fatty Acid Bioavailability.

Phospholipids (PL) or partial acylglycerols such as sn-1(3)-monoacylglycerol (MAG) are potent dietary carriers of long-chain polyunsaturated fatty acids (LC-PUFA) and have been reported to provide superior bioavailability when compared to conventional triacylglycerol (TAG). The main objective of the present study was to compare the incorporation of docosahexaenoic acid (DHA) in plasma, erythrocytes, retina and brain tissues in adult rats when provided as PL (PL-DHA) and MAG (MAG-DHA). Conventional dietary DHA oil containing TAG (TAG-DHA) as well as control chow diet were used to evaluate the potency of the two alternative DHA carriers over a 60-day feeding period. Fatty acid profiles were determined in erythrocytes and plasma lipids at time 0, 7, 14, 28, 35 and 49 days of the experimental period and in retina, cortex, hypothalamus, and hippocampus at 60 days. The assessment of the longitudinal evolution of DHA in erythrocyte and plasma lipids suggest that PL-DHA and MAG-DHA are efficient carriers of dietary DHA when compared to conventional DHA oil (TAG-DHA). Under these experimental conditions, both PL-DHA and MAG-DHA led to higher incorporations of DHA erythrocytes lipids compared to TAG-DHA group. After 60 days of supplementation, statistically significant increase in DHA level incorporated in neural tissues analyzed were observed in the DHA groups compared with the control. The mechanism explaining hypothetically the difference observed in circulatory lipids is discussed.

Development of self-microemulsifying drug delivery system for oral delivery of poorly water-soluble nutraceuticals.

The objective of the study was to develop a self-microemulsifying drug delivery system (SMEDDS), also known as microemulsion preconcentrate, for oral delivery of five poorly water-soluble nutraceuticals or bioactive agents, namely, vitamin A, vitamin K2, coenzyme Q10, quercetin and trans-resveratrol. The SMEDDS contained a 1:1 mixture (w/w) of Capmul MCM NF (a medium chain monoglyceride) and Captex 355 EP/NF (a medium chain triglyceride) as the hydrophobic lipid and Tween 80 (polysorbate 80) as the hydrophilic surfactant. The lipid and surfactant were mixed at 50:50 w/w ratio. All three of the SMEDDS components have GRAS or safe food additive status. The solubility of nutraceuticals was determined in Capmul MCM, Captex 355, Tween 80, and the SMEDDS (microemulsion preconcentrate mixture). The solubility values of vitamin A palmitate, vitamin K2, coenzyme Q10, quercetin, and trans-resveratrol per g of SMEDDS were, respectively, 500, 12, 8, 56, and 87 mg. Appropriate formulations of nutraceuticals were prepared and filled into hard gelatin capsules. They were then subjected to in vitro dispersion testing using 250 mL of 0.01 N HCl in USP dissolution apparatus II. The dispersion test showed that all SMEDDS containing nutraceuticals dispersed spontaneously to form microemulsions after disintegration of capsule shells with globule size in the range of 25 to 200 nm. From all formulations, except that of vitamin K2, >80-90% nutraceuticals dispersed in 5-10 min and there was no precipitation of compounds during the test period of 120 min. Some variation in dispersion of vitamin K2 was observed due to the nature of the material used (vitamin K2 pre-adsorbed onto calcium phosphate). The present report provides a simple and organic cosolvent-free lipid-based SMEDDS for the oral delivery of poorly water-soluble nutraceuticals. Although a 50:50 w/w mixture of lipid to surfactant was used, the lipid content may be increased to 70:30 without compromising the formation of microemulsion.

Effect of the supplementation with a blend containing short and medium chain fatty acid monoglycerides in milk replacer on rumen papillae development in weaning calves.

Feeding of neonates with artificial milk formulas is a popular trend toward early weaning of newborn dairy calves. These milk replacers (MR) should accelerate the rumen development, determining early solid feed intake and leading to better performances in cattle. Previous research demonstrated that sodium butyrate supplementation in MR can affect both small intestine and rumen development. Also acetate and propionate showed similar properties, while only a few studies indicate some potential benefit of monoglycerides on gut functions. The present study is aimed to determine the effect of the supplementation of a blend containing short and medium chain fatty acids monoglycerides (SMCFA) in milk replacer on rumen papillae development and growth performances in weaning calves. Twenty bull calves (about 2 weeks old, weighing around 43kg) were randomly allocated into two groups: control (C) and treated (T). Besides MR and starter diet, the latter offered at libitum, T calves received 0.2% SMCFA in MR. Animals were slaughtered after 56 days from the beginning of the trial. No difference was found between groups either in growth performances or in mean number of papillae/cm(2) of mucosa, total surface of papillae (mm(2))/cm(2) of mucosa or papillary size. In both groups, the morphology of the rumen epithelium was typical of parakeratosis. The cells of the stratum spinosum were directly transformed into swollen, ovoid, still nucleated keratinocytes, particularly at the papillary tip, probably as a result of unphysiological osmolarities caused by high concentrate intake. Degenerated squamous horn cells covered the "balloon like" cells forming several layers, particularly in the places of the rumen mucosa more protected from an abrasive action of solid feed. This was more evident in C animals. The squamous cells covering the papillary tip showed cytoplasmic protrusion, representing remains of the attachment sites of desmosomes, which increased the total absorptive surface and were more numerous and higher in T compared to C animals. It might be hypothesized that SMCFA supplementation in MR could better regulate epithelial cell proliferation and probably have an "emollient effect" leading to an easier "peeling" that might increase efficiency for nutrient transport across the epithelium.

MAG-EPA reduces severity of DSS-induced colitis in rats.

Ulcerative colitis (UC) is a chronic disease characterized by diffuse inflammation of the intestinal mucosa of the large bowel. Omega-3 (ω3) fatty acid supplementation has been associated with a decreased production of inflammatory cytokines involved in UC pathogenesis. The aim of this study was to determine the preventive and therapeutic potential of eicosapentaenoic acid monoglyceride (MAG-EPA) in an in vivo rats model of UC induced by dextran sulfate sodium (DSS). DSS rats were untreated or treated per os with MAG-EPA. Morphological, histological, and biochemical analyses were performed following MAG-EPA administrations. Morphological and histological analyses revealed that MAG-EPA pretreatment (12 days pre-DSS) and treatment (6 days post-DSS) exhibited strong activity in reducing severity of disease in DSS rats. Following MAG-EPA administrations, tissue levels of the proinflammatory cytokines TNF-α, IL-1ß, and IL-6 were markedly lower compared with rats treated only with DSS. MAG-EPA per os administration decrease neutrophil infiltration in colon tissues, as depicted by myelohyperoxidase activity. Results also revealed a reduced activation of NF-κB pathways correlated with a decreased expression of COX-2 in colon homogenates derived from MAG-EPA-pretreated and treated rats. Tension measurements performed on colon tissues revealed that contractile responses to methacholine and relaxing effect induced by sodium nitroprusside were largely increased following MAG-EPA treatment. The combined treatment of MAG-EPA and vitamin E displayed an antagonistic effect on anti-inflammatory properties of MAG-EPA in DSS rats.

A controlled trial on the effect of feeding dietary chestnut extract and glycerol monolaurate on liver function in newborn calves.

Beginning in the fall of 2010, an increasing and alarming number of cases of calves suffering from liver dystrophy were reported in the south of Germany. An epidemiological investigation was carried out by the authors between November 2010 and July 2011, leading to the implication of a commercial dietary supplement as the potential cause for this outbreak. The components of this product were first tested in a cell culture model and two of them (dietary chestnut extract and glycerol monolaurate) showed a cytotoxic effect. The objective of this study was therefore to evaluate the effect of supplemental feeding of both components alone or in combination on liver function in newborn calves on a commercial dairy farm. Ten calves were enrolled in each of the three treatment groups and the control group (group O) following a blocked design. Treatment consisted of supplementation with chestnut extract at 0.02% of birth body mass (BM) (group C), supplementation with glycerol monolaurate at 0.006% of BM (group G) or a combined treatment (group CG) for five consecutive days. The effect of treatments on liver function was evaluated clinically and by measurement of glutamate dehydrogenase (GLDH) and aspartate aminotransferase (AST) activities as well as the determination of the concentrations of glucose, L-lactate and total bilirubin in serum. There was a significant increase in GLDH and AST activities and a significant decrease in glucose concentration in treatment groups C and CG compared with the control group (p ≤ 0.035), whereas no difference was shown for group G. Survival was significantly decreased in groups C (p = 0.029) and CG (p = 0.001) compared with both group G and the control group. These results suggest that dietary chestnut extract in an amount of 0.02% of BM alone or in combination has a toxic effect on liver function in newborn calves.

MAG-EPA resolves lung inflammation in an allergic model of asthma.

BACKGROUND: Asthma is a chronic disease characterized by airways hyperresponsiveness, inflammation and airways remodelling involving reversible bronchial obstruction. Omega-3 fatty acids and their derivatives are known to reduce inflammation in several tissues including lung. OBJECTIVES: The effects of eicosapentaenoic acid monoacylglyceride (MAG-EPA), a newly synthesized EPA derivative, were determined on the resolution of lung inflammation and airway hyperresponsiveness in an in vivo model of allergic asthma. METHODS: Ovalbumin (OVA)-sensitized guinea-pigs were treated or not with MAG-EPA administered per os. Isometric tension measurements, histological analyses, homogenate preparation for Western blot experiments or total RNA extraction for RT-PCR were performed to assess the effect of MAG-EPA treatments. RESULTS: Mechanical tension measurements revealed that oral MAG-EPA treatments reduced methacholine (MCh)-induced bronchial hyperresponsiveness in OVA-sensitized guinea-pigs. Moreover, MAG-EPA treatments also decreased Ca(2+) hypersensitivity of bronchial smooth muscle. Histological analyses and leucocyte counts in bronchoalveolar lavages revealed that oral MAG-EPA treatments led to less inflammatory cell recruitment in the lung of OVA-sensitized guinea-pigs when compared with lungs from control animals. Results also revealed a reduction in mucin production and MUC5AC expression level in OVA-sensitized animals treated with MAG-EPA. Following MAG-EPA treatments, the transcript levels of pro-inflammatory markers such as IL-5, eotaxin, IL-13 and IL-4 were markedly reduced. Moreover, per os MAG-EPA administrations reduced COX2 over-expression in OVA-sensitized animals. CONCLUSION AND CLINICAL RELEVANCE: We demonstrate that MAG-EPA reduces airway hyperresponsiveness and lung inflammation in OVA-sensitized animals, a finding consistent with a decrease in IL-4, IL-5, IL-13, COX-2 and MUC5AC expression levels in the lung. The present data suggest that MAG-EPA represents a new potential therapeutic strategy for resolving inflammation in allergic asthma.

Activity of virgin coconut oil, lauric acid or monolaurin in combination with lactic acid against Staphylococcus aureus.

The objective of this study was to investigate the in vitro activities of virgin coconut oil, lauric acid and monolaurin in combination with lactic acid against two strains of Staphylococcus aureus, ATCC 25923 and an isolate from a pig carcass, by determination of Fractional Bactericidal Concentration Index (FBCI), time-kill method, as well as scanning and transmission electron microscopy. Minimum bactericidal concentrations (MBC) of lauric acid, monolaurin and lactic acid were 3.2 mg/ml, 0.1 mg/ml and 0.4% (v/v), respectively. The effects of lauric acid + lactic acid and monolaurin + lactic acid combinations were synergistic against both strains, exhibiting FBCIs of 0.25 and 0.63, respectively. In time-kill studies, lauric acid and monolaurin + lactic acid combinations added at their minimum inhibitory concentrations produced a bactericidal effect. The induction of stress in non-stressed cells was dependent on the type and concentration of antimicrobial. This resulted in a loss and change of the cytoplasm and membrane in cells of the bacterium. In contrast, virgin coconut oil (10%) was not active against S. aureus. The bacterial counts found in pork loin treated with lauric acid and monolaurin alone were significantly higher (p <0.05) than those treated with both lipids in combination with lactic acid at sub-inhibitory concentrations. The color, odor and overall acceptability of the pork loins were adversely affected by treatment with the three lipids and lactic acid alone but when combinations of the agents were used the sensory quality was acceptable.

Monoglycerides and fatty acids from Ibervillea sonorae root: isolation and hypoglycemic activity.

Eleven monoglycerides (MG), 1-monopalmitin (1), glyceryl 1-monomargarate (2), 1-monostearin (3), glyceryl 1-monononadecylate ( 4), glyceryl 1-monoarachidate (5), glyceryl 1-monobehenate (6), glyceryl 1-monotricosanoate (7), glyceryl 1-monotetracosanoate (8), glyceryl 1-monopentacosanoate (9), glyceryl 1-monohexacosanoate (10) and glyceryl 1-monooctacosanoate (11), together with five fatty acids (FA), lauric acid (12), myristic acid (13), pentadecanoic acid (14), palmitic acid (15) and stearic acid (16) were isolated of the root of IBERVILLEA SONORAE Greene (Cucurbitaceae). Their structures were determined by spectroscopic and chemical methods as well as GC-MS analysis. The hypoglycemic activity of the dichloromethane (DCM) extract, of fractions (F1-F10 and SF1-SF5), of monoglycerides (MG) and of fatty acids (FA) mixtures obtained of the root from I. SONORAE was evaluated in normoglycemic and alloxan-induced diabetic mice. The results showed that by intraperitoneal administration the DCM extract (300 mg/kg), F9 (300 mg/kg) and SF1 (150 mg/kg) significantly reduced glucose levels in both models. For fraction SF1, the hypoglycemic activity was more pronounced than that of tolbutamide (150 mg/kg) used as control. However, neither MG (75 mg/kg) nor FA (75 mg/kg) mixtures isolated from SF1 exhibited a significant hypoglycemic effect. However, when MG and FA were combined in equal proportions (75 mg: 75 mg/kg), their effect was comparable to that of SF1. The observed activity for the DCM extract, F9, SF1 and the MG-FA mixture provides additional support for the popular use of this plant in the treatment of diabetes mellitus in Mexican traditional medicine.