Plant sterols (PS) have many beneficial functions, like LDL-cholesterol reduction upon other effects on lipid parameters. PS are prone to oxidation and can give rise to plant sterol oxidation products (POPs), which have been suggested to be cytotoxic. The aim was to evaluate the bioaccesibility of phytosterols and their oxides in fruit and/or milk based beverages enriched with PS after a simulated gastrointestinal digestion. Four PS-fortified beverages were analyzed (fruit beverages without milk (Fb), with milk (Fb’M), with β-cryptoxanthin (FbM) and only milk (M)) and their corresponding bioaccessible fractions (BF). PS source was the same (0.7 g/100 g) for all the samples. The applied in vitro digestion method was according to Granado et al. (2007) to obtain the BF (soluble fraction). The extraction and purification of PS and POPs was achieved by lipid extraction (for the beverages), followed by saponification, unsaponificable extraction and silica SPE purification (only for POPs). They were determined by GC-FID (PS) and GC-MS (POPs). Total contents of PS in the analyzed beverages ranged between 607.08 and 743.05 mg/100 g beverage. The concentration order of PS was β-sitosterol > sitostanol > campesterol > stigmasterol > campestanol. A statistically significative (p <0.05) decrease in the PS content among beverages and the BAF (22.23-44.98 mg/100 g beverage) was observed, even though the relative percentages of the different PS were similar before and after digestion process. Total POP contents in the beverages ranged between 47.64 and 68.97 μg/100 g sample and 31.05-44.31 μg/100 g sample in the beverages and the BF, respectively. In all cases, β-sitosterol oxides (α/β-hydroxy, triol and 7-keto) were the only POPs detected. In the beverages, the most abundant oxide was 7-keto, whereas in the BF triol was the main one. The profile of POPs depended on the beverage or BF considered. Bioaccessibility (%) of PS and POPs were 2.99–7.41 and 34.17–93.01, respectively. The effect of simulated gastrointestinal digestion applied to PS and POPs studied, resulted to be different, showing that POPs bioaccessibility is much more higher than that of PS.
Bioaccesibility of plant sterols and their oxides in enriched fruit and/or milk-based beverages / L. Alemany; J. M. Laparra; G. García-Llatas; M.T. Rodriguez-Estrada; R. Barberá; A. Alegría. - STAMPA. - (2012), pp. 61-61. (Intervento presentato al convegno 1st International Conference on Food Digestion tenutosi a Cesena (Italia) nel March 19-21, 2012).
Bioaccesibility of plant sterols and their oxides in enriched fruit and/or milk-based beverages
RODRIGUEZ ESTRADA, MARIA TERESA;
2012
Abstract
Plant sterols (PS) have many beneficial functions, like LDL-cholesterol reduction upon other effects on lipid parameters. PS are prone to oxidation and can give rise to plant sterol oxidation products (POPs), which have been suggested to be cytotoxic. The aim was to evaluate the bioaccesibility of phytosterols and their oxides in fruit and/or milk based beverages enriched with PS after a simulated gastrointestinal digestion. Four PS-fortified beverages were analyzed (fruit beverages without milk (Fb), with milk (Fb’M), with β-cryptoxanthin (FbM) and only milk (M)) and their corresponding bioaccessible fractions (BF). PS source was the same (0.7 g/100 g) for all the samples. The applied in vitro digestion method was according to Granado et al. (2007) to obtain the BF (soluble fraction). The extraction and purification of PS and POPs was achieved by lipid extraction (for the beverages), followed by saponification, unsaponificable extraction and silica SPE purification (only for POPs). They were determined by GC-FID (PS) and GC-MS (POPs). Total contents of PS in the analyzed beverages ranged between 607.08 and 743.05 mg/100 g beverage. The concentration order of PS was β-sitosterol > sitostanol > campesterol > stigmasterol > campestanol. A statistically significative (p <0.05) decrease in the PS content among beverages and the BAF (22.23-44.98 mg/100 g beverage) was observed, even though the relative percentages of the different PS were similar before and after digestion process. Total POP contents in the beverages ranged between 47.64 and 68.97 μg/100 g sample and 31.05-44.31 μg/100 g sample in the beverages and the BF, respectively. In all cases, β-sitosterol oxides (α/β-hydroxy, triol and 7-keto) were the only POPs detected. In the beverages, the most abundant oxide was 7-keto, whereas in the BF triol was the main one. The profile of POPs depended on the beverage or BF considered. Bioaccessibility (%) of PS and POPs were 2.99–7.41 and 34.17–93.01, respectively. The effect of simulated gastrointestinal digestion applied to PS and POPs studied, resulted to be different, showing that POPs bioaccessibility is much more higher than that of PS.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
