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Dietary modifications including plant stanol ester consumption are recommended measures to control serum and low-density lipoprotein (LDL)-cholesterol concentrations, but obesity can affect their responses. We investigated whether body mass index (BMI) affects serum cholesterol levels during plant stanol (mainly sitostanol) ester consumption. This ad hoc analysis was based on earlier results of a cross-over, randomized controlled trial of postmenopausal women consuming rapeseed oil-based margarine without or with plant stanol ester (3 g plant stanols/day) for seven weeks. We classified the subjects as normal-weight (BMI ≤ 25 kg/m2, n = 9, mean 22.6 kg/m2) or overweight/obese (BMI > 25 kg/m2, n = 11, mean 28.4 kg/m2), and recalculated the results, focusing on cholesterol absorption, cholesterol synthesis, and fecal steroid outputs. Serum cholesterol levels were similar in the groups during the control diet. Plant stanol ester reduced serum cholesterol by 0.63 ± 0.19 mmol/L (11%) in normal-weight and by 0.75 ± 0.13 mmol/L (12%) in overweight/obese subjects (p < 0.05 for both), and cholesterol absorption was reduced in both groups. However, relative and dietary cholesterol absorption were more effectively reduced in normal-weight subjects. In conclusion, overweight/obesity did not interfere with the serum cholesterol response to plant stanol ester consumption despite substantial differences in cholesterol metabolism between the groups.

A cascade process for the sequential recovery of proteins and feruloylated arabinoxylan from wheat bran is proposed, involving a protein isolation step, enzymatic destarching and subcritical water extraction. The protein isolation step combining lactic acid fermentation and cold alkaline extraction reduced the recalcitrance of wheat bran, thus improving the total yields of the subsequent subcritical water extraction. The time evolution of subcritical water extraction of feruloylated arabinoxylan was compared at two temperatures (160 °C and 180 °C). Longer residence times enhanced the purity of target feruloylated arabinoxylans, whereas higher temperatures resulted in faster extraction at the expense of significant molar mass reduction. The radical scavenging activity of the extracted feruloylated arabinoxylans was preserved after the initial protein isolation step. This study opens new possibilities for the cascade valorization of wheat bran into enriched protein and non-starch polysaccharide fractions, which show potential to be used as functional food ingredients.

The effect of three combinations of bioprocessing methods by lactic acid fermentation, cell wall hydrolyzing enzymes and phytase on the biochemical (protein, fat, carbohydrate composition) and technofunctional properties (protein solubility, emulsifying and foaming properties) of wheat bran protein isolates were evaluated. The bioprocessing increased the protein (up to 80%) and fat content (up to 22.8%) in the isolates due to the degradation of starch and soluble pentosans. Additional proteins, globulin 3A and 3C, chitinase, beta-amylase and LMW glutenins, were identified from the electrophoretic pattern of the protein isolate bioprocessed with added enzymes. Generally, the bioprocessed protein isolate had lower protein solubility and stronger net charge in pH below 7, when compared to the protein isolate made without bioprocessing. The emulsifying properties of the protein isolates were not affected by bioprocessing. However, the foaming stability of the protein isolates was nearly doubled by bioprocessing with cell wall hydrolyzing enzymes and phytase.

Besides providing dietary fiber, wheat bran is a recognized source of protein and is considered a very valuable substitute for other protein-rich sources in the food and feed industry. Nonetheless, several factors affect protein bioavailability, including bran's layered structure. This study showed the influence on the release and protein modification of wheat bran of different bioprocessing methods involving the activation of endogenous enzymes of bran, the addition of an enzyme mixture having carbohydrase activity, and microbial fermentation. Bioprocessing in acidic conditions significantly enhanced the solubilization of protein from wheat bran, reaching the highest value in the treatment where the sole endogenous protease activity was activated. Bioprocessing through controlled fermentation allowed a more intense proteolysis and strongly impacted the in vitro digestibility of proteins. The combined use of starter cultures and cell-wall-degrading enzymes was characterized by the highest increase of phytase activity and total phenols.

Wheat bran contains good quality protein, but given its location inside aleurone cells, this protein has restricted digestibility. The aim of this work was to liberate and solubilize wheat bran proteins via cell wall degradation by using carbohydrate-hydrolyzing and proteolytic enzymes without causing extensive protein hydrolysis. Bran incubated with water (without added enzymes) for 16 h increased the solubilized organic nitrogen content from 14.0 to 42.8%. Enzymes with solely carbohydrate-hydrolyzing activity increased the water-soluble pentosan and reducing sugar contents but did not significantly increase protein solubilization or protein release from the aleurone cells. Enzymes with proteolytic activity significantly increased the solubilization of protein to 58.2% already at 4 h. Significant protein hydrolysis was detected with a high dosage of protease. However, based on light microscopy, the enzymatic treatment mainly modified the proteins in the subaleurone layer, and it was less effective on proteins inside the aleurone cells. With optimized protease treatment (3 h, 35°C, and 550 nkat/g), effective protein solubilization (>48%) without extensive protein hydrolysis (free amino nitrogen content