Formulating healthy food rich in omega 3 fatty acids requires prior knowledge of the parameters influencing their bioavailability and their metabolic fate. In this context, we studied the effects of various emulsifiers widely used in the food industry, on the gastrointestinal lipolysis of flaxseed oil emulsions in an in vitro model and on the intestinal absorption and lymphatic secretion of alpha-linolenic acid (ALA) in rats. In vitro data showed that the emulsification of flaxseed oil with soya lecithin improved the gastric lipolysis of the oil (+30%), while the presence of Tween 80 or of sodium caseinate decreased it (−80% and −40%, respectively). The in vivo data demonstrated that the intestinal absorption and the lymphatic secretion of ALA were improved with soya lecithin (C_max = 24 mg mL⁻¹) and reduced in the presence of sodium caseinate (C_max = 7 mg mL⁻¹) compared to unemulsified flaxseed oil (C_max = 16 mg mL⁻¹); Tween 80 had no effect. In addition, the synthesized chylomicrons were notably larger and more numerous with soya lecithin whereas they were smaller in the presence of sodium caseinate (p < 0.05). This study shows that the intestinal bioavailability of ALA was increased by the emulsification of flaxseed oil with soya lecithin via an improved lipolysis, favouring the intestinal absorption of ALA and the secretion of many large chylomicrons in lymph.

The present study aims at clarifying the impact of oxidative stress on type B trichothecene production. The responses to hydrogen peroxide (H2O2) of

The bioavailability of α-linolenic acid (ALA) from flaxseed oil in an emulsified formv.a non-emulsified form was investigated by using two complementary approaches: the first one dealt with the characterisation of the flaxseed oil emulsion inin vitrogastrointestinal-like conditions; the second one compared the intestinal absorption of ALA in rats fed the two forms of the oil. Thein vitrostudy on emulsified flaxseed oil showed that decreasing the pH from 7·3 to 1·5 at the physiological temperature (37°C) induced instantaneous oil globule coalescence. Some phase separation was observed under acidic conditions that vanished after further neutralisation. The lecithin used to stabilise the emulsions inhibited TAG hydrolysis by pancreatic lipase. In contrast, lipid solubilisation by bile salts (after lipase and phospholipase hydrolysis) was favoured by preliminary oil emulsification. Thein vivoabsorption of ALA in thoracic lymph duct-cannulated rats fed flaxseed oil, emulsified or non-emulsified, was quantified. Oil emulsification significantly favoured the rate and extent of ALA recovery as measured by the maximum ALA concentration in the lymph (C_max = 14 mg/ml at 3 h in the emulsion groupv.9 mg/ml at 5 h in the oil group;P < 0·05). Likewise, the area under the curve of the kinetics was significantly higher in the emulsion group (48 mg × h/ml for rats fed emulsionv.26 mg × h/ml for rats fed oil;P < 0·05). On the whole, ALA bioavailability was improved with flaxseed oil ingested in an emulsified state. Data obtained from thein vitrostudies helped to partly interpret the physiological results.

Long-chain polyunsaturated fatty acids (LC-PUFAs) are important for newborn neurosensory development. Supplementation of breastfeeding mothers’ diets with omega-3 PUFAs, such as alpha-linolenic acid (ALA), may increase their concentration in human milk. This study aimed to assess human milk composition after 15-day supplementation regimens containing either omega-3 PUFAs or olive oil, which does not provide ALA. A multicenter factorial randomized trial was conducted with four groups of breastfeeding women, with each group containing 19 to 22 women. After a 15-day ALA washout period, three groups received supplementation with omega-3 precursors for 15 days: an enriched margarine (M), a rapeseed oil (R), and a margarine and rapeseed oil (MR). The fourth was unexposed to omega-3 precursors (olive oil control diet, O). After 15 days, blind determination of human milk fatty acid (FA) composition was assessed by gas chromatography, and the FA composition was compared among groups using variance analyses. Alpha-linolenic acid content, expressed as the mean (standard deviation) total human milk FA percentage, was significantly higher after diet supplementation with omega-3 PUFAs, with values of 2.2% (0.7%) (MR), 1.3% (0.5%) (R), 1.1% (0.4%) (M), and 0.8% (0.3%) (O at D30) (p < .003 for each comparison). The lowest LA–ALA ratio (5.5) was found in the MR group (p < .001). Docosahexaenoic acid and trans FA concentrations did not differ among groups. In lactating women, omega-3 supplementation via the combination of enriched margarine and rapeseed oil increased the ALA content of human milk and generated the most favorable LA–ALA ratio for LC-PUFA synthesis.

Little is known about the ability of α-linolenic acid (Ln) to remain in the sn-2 position of TG during the absorption process. The goal of this study