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From 98 Lactobacillus strains, isolated from Algerian homemade cheeses, 14 (B1-B14) were selected based on their anti-Escherichia coli and anti-Staphylococcus aureus activities. These strains were also tested towards Listeria monocytogenes 161 and Salmonella Typhimurium LT2 and further investigated for their resistance to simulated gastrointestinal digestion, cell surface properties, ability to adhere to HT-29 cells, cholesterol lowering, antioxidant activity, and technological traits. Five isolates (B9, B13, B18, B19, and B38) were active against L. monocytogenes and Salmonella. From them, three isolates, identified as Lactobacillus brevis (B9, B13, and B38) by MALDI-TOF spectrometry and 16S rDNA sequencing, exhibited high tolerance to pancreatic juice, bile salts and acidic juices, high percentages of hydrophobicity (87, 92, and 81%, respectively), auto-aggregation (61, 68, and 72%, respectively), and adherence to HT-29 cells (79, 84, and 74%, respectively), which testify on their potential of colonization of the human intestine. On the other way, the strains B9 and B13 manifested the most relevant antioxidant activity and cholesterol-lowering ability, respectively. L. brevis strains showed low acidifying and good proteolytic activities with noticeable heat tolerance. The results gathered in this study highlighted the richness of Algerian artisanal cheeses on new lactobacilli strains with an excellent probiotic potential and demonstrated that L. brevis, largely used as nonstarter in cheese manufacture, could be exploited also as a probiotic for human use. [ABSTRACT FROM AUTHOR]

In this study, proteins were extracted from tomato seeds, the main by-product of tomato processing. The incubation for 138.62 min coupled with 3% alcalase was observed to be optimum to produce a tomato seed protein hydrolysate (TSPH) with the highest antioxidant properties. Under these conditions, predicted TSPH activities were 62.99% scavenging of DPPH radicals and 54.81% reduction of phosphomolybdate. Separation of TSPH by ultrafiltration provided three fractions (UF1-UF3) of which, UF3 (< 3 kDa) showed the strongest activity (73.15% DPPH scavenging and 60.1% phosphomolybdate reduction). UF3 was further separated by RP-HPLC into sub-fractions F1-F6. Biological testing found that F2 and F4 were the most active in scavenging DPPH radicals (60.36 and 21.23%) and reducing phosphomolybdate (57.3 and 48.0%). LC-ESI-MS/MS analysis showed that the higher activity of F2 might be explained by the presence of more peptides that contained tyrosine and histidine, known to enhance antioxidant activity through hydrogen or electron transfer. In the simulated gastrointestinal digestion test, peptides in F2 were more resistant compared to those in F4. These findings indicate that peptide fraction F2 might be more useful in the formulation of functional foods because of its greater antioxidant activity and resistance to digestion. [ABSTRACT FROM AUTHOR]

Optimization conditions for alkylresorcinols (ARs) extraction from triticale bran were determined using response surface methodology. A central composite design was used to determine the effects of extraction temperature (degrees Celsius) and solid-to-solvent ratio (weight per volume) on yield of saturated, unsaturated and total ARs. Extraction of ARs was affected significantly ( p value ≤ 0.05) by temperature and solid-to-solvent ratio on the yield of saturated, unsaturated and total ARs. The highest quantity of total ARs from triticale bran was extracted at 24 °C between 16 and 24 h at a solid-to-solvent ratio (weight per volume) of 1:40 and ranged from 278 to 308 mg/100 g, while saturated and unsaturated ARs were 163 to 225 mg/100 g and 22 to 29 mg/100 g, respectively. The ARs identified by high-performance liquid chromatography included: C15:0, C17:0, C19:0, C21:0, C23:0 and C25:0. Also some unsaturated analogues (12.4% to 14.0%) were found including C17:1, C19:1, C21:1 and C23:1. Analysis of variance ( p value = 0.05) indicated that the response surface methodology (RSM) developed for saturated, unsaturated and total ARs were adequate and explained most of the variability (85% to 89%) with high coefficient of multiple determination ( R = 0.89). The main effect of the response variable was quadratic rather than a linear function. Our results showed that RSM is a tool that is useful to optimise experimental conditions for the extraction of ARs. [ABSTRACT FROM AUTHOR]

The objectives of this study were to: i) define the optimum concentration of triticale bran (TB) that can be incorporated in yogurt, ii) evaluate the prebiotic effects of TB on microbial viability, pH and total titratable acidity (TTA) in yogurt across 28 days of cold storage, and iii) measure the oxygen radical absorbance capacity (ORAC) of water-extractable polysaccharides (WEP) in TB. Lactobacillus bulgaricus and Streptococcus thermophilus were used as starter cultures. Lactobacillus acidophilus and Bifidobacterium lactis were used as probiotics. A concentration of 4% TB in yogurt was determined to be the maximum amount that could be added without causing synersis. By day 7, the number of bacteria greatly increased in yogurt samples containing TB and maintained higher viable bacteria counts at the end of the cold storage period, in comparison to controls ( P ≤ 0.05). Confirming this data was the lower pH levels and higher TTA values of TB yogurt samples exhibited throughout 28 days ( P ≤ 0.05). Polysaccharide extracts of TB exhibited strong antioxidant activity with an ORAC value of 33.86 ± 2.30 μmol trolox equivalents (TE)/g of bran. Results of this study suggest that TB may serve as a new prebiotic and antioxidant source for functional foods and nutraceutical applications. [ABSTRACT FROM AUTHOR]