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Lactic acid bacteria (LAB) are ubiquitous bacteria associated with spontaneous lactic fermentation of vegetables, dairy and meat products. They are generally recognized as safe (GRAS), and they are involved in transformation of probiotic lacto-fermented foods, highly desired for their nutraceutical properties. The antifungal activity is one of the exciting properties of LAB, because of its possible application in food bio-preservation, as alternative to chemical preservatives. Many recent research works have been developed on antifungal activity of LAB, and they demonstrate their capacity to produce various antifungal compounds, (i.e. organic acids, PLA, proteinaceous compounds, peptides, cyclic dipeptides, fatty acids, and other compounds), of different properties (hydrophilic, hydrophobic and amphiphilic). The effectiveness of LAB in controlling spoilage and pathogenic fungi, demonstrated in different agricultural and food products, can be due to the synergistic effect between their antifungal compounds of different properties; where the amphiphilic-compounds allow the contact between the target microbial cell (hydrophilic compartment) and antifungal hydrophobic-compounds. Further studies on the interaction between compounds of these three properties are to de be developed, in order to highlight more their mechanism of action, and make LAB more profitable in improving shelf life and nutraceutical properties of foods.

The microwave-assisted extractions (MAE) of Ocimum basilicum L. (basil) seed, Trigonella foenum-graecum (fenugreek) seed, and Plantago ovata Forsk (psyllium) seed husk hydrocolloids (BSH, FSH, and PSH, respectively) were performed at their maximum desirability function (for BSH) or optimum (for FSH and PSH) conditions and compared with conventional heating extraction (CHE). The extraction conditions had been defined based on two responses (Yield % and viscosity, mPa s) after relevant post-screening or optimization experiments based on previous experiments. Higher (17.89, 12.33, 32.60, 30.19, 71.73%) average extraction yields were obtained for BSH extracted by MAE (MAE-BSH), BSH extracted by CHE (CHE-BSH), FSH extracted by MAE (MAE-FSH), FSH extracted by CHE (CHE-FSH), and PSH extracted by MAE (MAE-PSH) in respective order compared with the estimated values (15.03, 9.96, 32, 22, and 65.4). Molecular weight (Mw) measurements were executed and the average Mw was determined to be 3.93 × 106, 2.89 × 106, 6.81 × 106 Da in the heavier fractions of BSH, FSH, and PSH. The FT-IR spectroscopy was performed and the predominant absorbance bands were defined. Dielectric properties of the 2% BSH, FSH, and PSH solutions were found to be comparable with distilled water. The steady flow analysis showed shear-thinning behavior for BSH, FSH, and PSH. The apparent viscosity (η, mPa s) of PSH was the highest followed by BSH and FSH. Dynamic flow measurements showed characteristics of a weak gel for BSH and PSH. Scanning electron microscopy showed morphological variations between the studied hydrocolloids. In addition, the study also indicated that microwave heating has lower destructive effects on the functional properties of the extract as compared to conventional thermal processing and could pave the way for future research. To conclude, MAE was found to be the efficient method for extraction of hydrocolloids with higher yield at a shorter extraction time.

Emulsions, hydrogels and emulgels have attracted a high interest as tools for the delivery of poorly soluble hydrophobic nutraceuticals by enhancing their stability and bioavailability. This review provides an overview of these delivery systems, their unique qualities and their interactions with the human gastrointestinal system. The modulation of the various delivery systems to enhance the bioavailability and modify the release profile of bioactive encapsulates is highlighted. The application of the delivery systems in the delivery of cannabinoids is also discussed. With the recent increase of cannabis legalization across North America, there is much interest in developing cannabis edibles which can provide a consistent dose of cannabinoids per portion with a rapid time of onset. Indeed, the long time of onset of psychoactive effects and varied metabolic responses to these products result in a high risk of severe intoxication due to overconsumption. Sophisticated emulsion or hydrogel-based delivery systems are one potential tool to achieve this goal. To date, there is a lack of evidence linking specific classes of delivery systems with their pharmacokinetic profiles in humans. More research is needed to directly compare different classes of delivery systems for the gastrointestinal delivery of cannabinoids.

This study demonstrated the use of ultrasound-assisted extraction to render aqueous extract polyphenolic compounds from olive leaves. Sodium caseinate-olive leaf extract complexes were produced using different amounts of olive leaf extract (0, 0.5, 1, 1.5, and 2% w/v). Turbidity, solubility, antioxidant activity (DPPH and ABTS assays), foaming capacity and stability and surface hydrophobicity tests were done on each sample. To study the interaction mechanisms and structural changes, fluorescence, and Fourier-transform infrared were performed. Oil-in-water emulsions of the complexes were prepared and analyzed for their emulsifying properties (emulsifying activity index and emulsifying stability index), rheological properties and viscosity. Addition of olive leaf extract at higher amounts (1.5 and 2%) enhanced the turbidity, water solubility, antioxidant activity, and foam capacity/stability of protein-polyphenol complexes. Moreover, it was found that non-covalent interactions mainly hydrogen bonds were the main interaction mechanism of sodium caseinate/ olive leaf extract complexes. Surface hydrophobicity of complexes decreased with increasing amount of olive leaf extract. In terms of emulsion formation, the activity and stability increased with increasing the concentration of olive leaf extract. Addition of olive leaf extract also slightly increased the viscosity and viscoelastic parameters (storage and loss modulus).

The unequivocal economical and social values of bread as a staple food commodity lead to constant interests in optimizing its postproduction quality and extending its shelf life, which is related to the maintenance and enhancement of flavors and textural properties, and finally, to the delay of microbial spoilage. The latter has been the subject of a multitude of studies and reviews, in which the different approaches and views were discussed. However, variations in bread freshness, flavor, and textural quality are still of concerns for the bread making industry, in conjunction with the expectation from consumers for bread products with high-quality attributes and free of synthetic ingredients that satisfy their pleasure and their sustainable lifestyle. This review mainly focuses on the quality profiles of bread, including flavor, rheological, textural, and sensorial aspects; on the modalities to assess them; as well as on the conventional and emerging approaches developed so far over the past decades. The applications of lactic acid bacteria (LAB) and enzymes as bioprotective technologies are examined and discussed, along with active packaging and novel processing technologies for either the maintenance or improvement of bread qualities during storage.

Using cranberry (Vaccinium macrocarpon L.) pomace as a starting material, the microwave-assisted production of extracts and their structural characterization were investigated. Three methods (acidic, alkaline, and sequential acid/alkaline) and two microwave power settings (36 and 72 W/g) were compared in terms of total yield and recovery of oligo/polysaccharides and phenolic compounds. Acid extraction led to the lowest yields of 3.4–4.9% (w/w), while alkaline extraction at 32 W/g resulted in a yield of 12.6% (w/w). Higher microwave power favored the release of high molecular weight polysaccharides (200–700 kDa). As compared to acidic and alkaline extractions, sequential one yielded pectic polysaccharides with the highest arabinan (Ara:Rha, 6.6:1) and galactan branching chains (Gal:Rha, 5.2:1) and the lowest proportion of monosaccharides (Glu, Xyl/Man) from hemicellulosic polysaccharides. Response surface methodology was used to optimize the microwave-assisted sequential extraction as it was identified as the most appropriate method for the production of highly branched pectic polysaccharides. Variables included pomace concentration (3.33–50.00 mg/ml solvent), sodium hydroxide concentration (0–2 M), time (1–6 min), and microwave power (35–80 W/g cell wall material). The sequential extraction conditions for the optimal extract yield (28.65%) were determined to be 0.1 M HCl/1.51 M NaOH, 65 W/g, 16.33 mg pomace/ml, and 4.73 min, at which polyphenols and oligo/polysaccharides recovery of 57.0% and 10.56%, respectively, were obtained. The composition and the molecular weight distribution confirmed the isolation of arabinan-rich RGI (GalA:Rha of 15.8:1; Ara:Rha of 5.7:1) type pectic polysaccharide extracts enriched with polyphenolic compounds.

During processing, cocoa bean shells (CBS) are de-hulled from the bean and discarded as waste. Undermined by its chemical and bioactive composition, CBS is abundant in dietary fiber and phenolic compounds that may serve the valorization purpose of this by-product material into prebiotic and functional ingredients. In addition, the cell-wall components of CBS can be combined through enzymatic feruloylation to obtain feruloylated oligo- and polysaccharides (FOs), further enhancing the techno-functional properties. FOs have attracted scientific attention due to their prebiotic, antimicrobial, anti-inflammatory and antioxidant functions inherent to their structural features. This review covers the chemical and bioactive compositions of CBS as well as their modifications upon cocoa processing. Physical, chemical, and enzymatic approaches to extract and bio-transform bioactive components from the cell wall matrix of CBS were also discussed. Although nonspecific to CBS, studies were compiled to investigate efforts done to extract and produce feruloylated oligo- and polysaccharides from the cell wall materials.

Feruloyl esterase (FAE)-catalyzed esterification reaction is as a potential route for the biosynthesis of feruloylated oligosaccharides as functional ingredients. Immobilization of FAE from Humicola insolens on metal chelate-epoxy supports was investigated. The study of effects of immobilization parameters using response surface methodology revealed the significance of enzyme/support ratio (3.25-29.25 mg/g support), immobilization time (14-38 h), buffer molarity (0.27-1.25 M) and pH (4.0-8.0). The interactions between enzyme-to-support ratio/buffer molarity and enzyme-to-support ratio/pH were found to be critical for the modulation of the immobilization activity yield and the retention of specific activity, respectively. Optimum conditions for FAE-immobilization on metal chelate Sepabeads® EC-EP R were identified to be 22.75 mg FAE/g support, pH of 5.0, 27.7 h and buffer molarity of 0.86 M. At these conditions, an activity yield of 82.4%, a specific activity retention of 143.4%, and an enzyme activity of 395.4 μmol/min. g support were achieved. Further incubation of the immobilized FAE at pH 10.0 improved its thermostability. Increasing the pore size of the epoxy support improved the retention of FAE hydrolytic activity and the esterifying efficiency of the immobilized biocatalyst. Optimally immobilized and stabilized FAE on metal chelate-epoxy support retained up to 92.9% of the free enzyme feruloylation efficiency to xylooligosaccharides..

Potato protein isolate and concentrate, recovered from a waste stream from the starch industry, potato fruit juice, were assessed as added-value ingredients for the enrichment of composite flours composed of wheat and rice flours with varying ratios to improve the quality attributes of reduced-gluten cookies. Bridging the analytical textural properties to the sensory results of a semi-trained panel contributed to the understanding of the quality attributes (textural, color, and sensory) that drive the overall acceptance. Potato protein isolate resulted in cookies, which bent more on first bite and were more texturally desired by a semi-trained panel compared with cookies prepared with potato protein concentrate. The effects of rice flour proportion (14.6–85.4%) and potato protein isolate enrichment (1.9–23.1%) were investigated using a central composite rotatable design. Logistic regression analysis of the sensory results (70 consumers) revealed that liking scores of overall liking, aftertaste, and crispness were the most determinants for the overall acceptance of reduced-gluten cookies enriched with potato protein isolate. Predictive mathematical models of the liking scores of these critical sensory attributes were developed. Based on the models, the level of potato protein isolate enrichment up to 7.2% produced acceptable reduced-gluten cookies, while improving the textural and sensorial characteristics when compared with rice flour alone.

Cranberry pomace obtained from industrial juice production was characterized by proximate composition analysis and monosaccharide profile of the dietary fiber. Extraction of carbohydrates from pomace was investigated using microwave-assisted alkaline method and five commercial biocatalysts (pure endo-galactanase and four multienzyme biocatalysts). The extracts obtained from microwave-assisted approach had average total sugars yield of 21.3% and contained mostly oligosaccharides in the degree of polymerization range of 7 to 10. All multienzyme biocatalysts led to yields similar or higher than microwave-assisted approach (23.4% to 42.0%), but mainly generated shorter oligosaccharides with a degree of polymerization of 2 to 5. Compared to cranberry pomace dietary fiber, microwave-assisted extracts were enriched in pectic oligosaccharides, whereas the enzymatic extracts were enriched in glucans and had less rhamnose and galactose. Pomace ground for 5 min or more by ball mill assumed a powdery consistence. Longer milling did not affect particle size but increased their roughness. Such physical changes had no effect on the efficiency of multienzymatic treatment. PRACTICAL APPLICATION: The increased production of cranberries and cranberry products will continuously generate more pomace, a potentially valuable material for the generation of added-value products. Up to 60% to 70% of cranberry pomace is composed of plant cell wall material. The properties of naturally occurring plant cell wall polysaccharides and their corresponding oligosaccharides have been of a great interest, and many of them find application as functional food ingredients. Despite the fact that the cranberry pomace is rich in plant cell polysaccharides, it has been mainly explored as a source of phenolic antioxidants. This study reveals the efficiency of cranberry pomace as a source of nondigestible oligosaccharides. The use of microwave-assisted extraction and different biocatalysts for the enzymatic extraction led to oligosaccharides with well-defined monosaccharide composition and molecular weight distribution. The study of the effects of these extraction techniques on the yield and the characteristics of generated oligosaccharides would allow the modulation of their properties. As an overall, the findings of this study would contribute to lay the scientific ground for the development of innovative process for the isolation of nondigestible oligosaccharides as functional ingredients from cranberry pomace by products.

Synthesis of carbohydrate fatty acid esters catalyzed by immobilized lipases is a pathway to obtain specific isomers from renewable feedstock, compared to unselective chemical esterification. While the use of low-solvent reaction media (≤ 10 %) offers advantages, the interactive effects of these media with biocatalysts and substrates should be modulated towards high catalytic efficiency and substrate availability. Among the investigated co-solvents, tert-butanol and DMSO in a mixture of lauric acid substrate/co-solvent (90/10; v/v) resulted in high bioconversion yields using either Novozym® 435 or Lipozyme® RM IM, as biocatalysts. Increased hydrophobicity of the Novozym® 435 immobilization support favored bioconversion, while polar substrate surface area enlargement by ball-milling improved productivity through enhancement of fructose availability. A compromise between bioconversion yield (19.7 %) and productivity (9.45 µmol/L min) was obtained in the reactions catalyzed by Novozym® 435 using ball-milled fructose at a concentration of 0.2 mol/L. Combining mechanical ball-milling of the substrates with low-solvent reaction media is expected to enhance and expand enzymatic synthesis of carbohydrate fatty acid esters.

Agriculture is facing many challenges, such as climate change, drought, and salinity, which call for urgent interventions for fast adaptation and crop diversification. The introduction of high-value and stress tolerant crops such as quinoa would be a judicious solution to overcome constraints related to abiotic stress and to increase land productivity and farmers’ incomes. The implementation of quinoa in Morocco has not been supported by a full valorization program to control the quality of quinoa seeds. The novelty of this work is to assess the pearling operation as an efficient method of saponins removal as well as the determination of total residual saponins. This study aimed to evaluate the effects of several pearling durations on nutrient and saponin content of quinoa seeds of three tested varieties (Puno, Titicaca, and ICBA-Q5). Five pearling durations were tested (0, 2, 4, 6, 7, and 8 min) using a locally manufactured pearling machine. The results indicated that a pearling duration of two minutes was enough to reduce total saponin content from 0.49% to 0.09% for Puno variety, from 0.37% to 0.07% for Titicaca variety, and from 0.57% to 0.1% for ICBA-Q5 variety. Our results showed that pearling slightly reduced protein, total fat, and moisture contents for all varieties except for Puno, where total fat content slightly increased with the pearling. Puno variety had the highest seed content in terms of protein and total fat, the ICBA-Q5 variety had the lowest. Titicaca had the highest bran content in terms of protein and total fat, ICBA-Q5 had the highest bran content in terms of ash and the lowest bran content in terms of protein and total fat, and Puno had the lowest bran content in terms of ash. Pearling had no significant effect on macronutrient contents in the processed seed, but it resulted in a very highly significant difference for most of them in the bran except for Mg and S. Regarding seed content in terms of micro-nutrients, statistical analysis showed significant differences between varieties in terms of Zn, Cu, and Mn contents, but no significant difference was recorded for Fe or B. Pearling had no significant effect on seed micronutrient contents. Therefore, to retain maximum nutritional content in the quinoa and maintain quinoa integrity, it is necessary to limit the pearling duration of quinoa to two minutes, which is enough to reduce saponin content below the Codex Standard threshold (0.12%).

The potential of poly- and oligosaccharides as functional ingredients depends on the type and glycosidic linkages of their monosaccharide residues, which determine their techno-functional properties, their digestibility and their fermentability. To isolate the pectic polysaccharides of cranberry, alcohol insoluble solids were first obtained from pomace. A sequential extraction with hot phosphate buffer, chelating agents (CH), diluted (DA) and concentrated sodium hydroxide was then carried out. Pectic polysaccharides present in CH and DA extracts were purified by anion exchange and gel filtration chromatography, then sequentially exposed to commercially available pectin-degrading enzymes (endo-polygalacturonase, pectin lyase and endo-arabinanase/endo-galactanase/both). The composition and linkages of the generated fragments revealed important characteristic features, including the presence of homogalacturonan with varied methyl esterification extent, branched type I arabinogalactan and pectic galactan. The presence of arabinan with galactose branches was suggested upon the analysis of the fragments by LC-MS.

International audience; The aim of this work is to characterize the potential probiotic properties of 14 antifungal Lactobacillus strains isolated from traditional fermenting Moroccan green olives. The molecular identification of strains indicated that they are composed of five Lactobacillus brevis, two Lactobacillus pentosus, and seven Lactobacillus plantarum. In combination with bile (0.3%), all the strains showed survival rates (SRs) of 83.19–56.51% at pH 3, while 10 strains showed SRs of 31.67–64.44% at pH 2.5. All the strains demonstrated high tolerance to phenol (0.6%) and produced exopolysaccharides. The autoaggregation, hydrophobicity, antioxidant activities, and surface tension value ranges of the strains were 10.29–41.34%, 15.07–34.67%, 43.11–52.99%, and 36.23–40.27 mN/m, respectively. Bacterial cultures exhibited high antifungal activity against Penicillium sp. The cell-free supernatant (CFS) of the cultures showed important inhibition zones against Candida pelliculosa (18.2–24.85 mm), as well as an antibacterial effect against some gram-positive and gram-negative bacteria (10.1–14.1 mm). The neutralized cell-free supernatant of the cultures displayed considerable inhibitory activity against C. pelliculosa (11.2–16.4 mm). None of the strains showed acquired or horizontally transferable antibiotic resistance or mucin degradation or DNase, hemolytic, or gelatinase activities. Lactobacillus brevis S82, Lactobacillus pentosus S75, and Lactobacillus plantarum S62 showed aminopeptidase, β-galactosidase, and β-glucosidase activities, while the other enzymes of API-ZYM were not detected. The results obtained revealed that the selected antifungal Lactobacillus strains are considered suitable candidates for use both as probiotic cultures for human consumption and for starters and as biopreservative cultures in agriculture, food, and pharmaceutical industries.

Agricultural production in the Rehamna region, Morocco is limited with various challenges including drought and salinity. Introduction of climate resilient and rustic crops such as quinoa was an optimal solution to increase farmer’s income and improve food security. This study summarizes results obtained from a research project aiming to develop quinoa value chain in Morocco. The study tackled several aspects including agronomic traits (yield and growth), transformation, quality (nutritional and antinutritional traits) and economic analysis and, finally, a strength–weaknesses–opportunities–threats analysis, lessons learned and development perspectives were presented. From an agronomic point of view, introduced new quinoa cultivars showed higher performance than locally cultivated seeds and, furthermore, the use of irrigation and organic amendment has tremendously improved seed yield by double and three times, respectively, compared to rainfed conditions. Nutritional analysis revealed that protein and phosphorus content remained stable after seed pearling while most of the micronutrients content decreased after seed pearling. However, saponins content was reduced by 68% using mechanical pearling compared to 57% using both traditional abrasion and washing. The economic analysis showed that production cost of quinoa seeds could be further decreased using mechanized intensive tools along with irrigation and organic amendment supply. This study revealed several lessons learned from the field experience and proposed several development actions for each value chain component that can be implemented within a national quinoa program.

Cranberries of Stevens variety, mainly used for juice production, were processed into pomace, from which alcohol insoluble solids (AIS) were obtained. The cell wall polysaccharides were sequentially extracted from AIS, and characterized in terms of monosaccharide profile, sugar linkage and molecular weight distribution. Pectic polysaccharides represented more than 90% of the carbohydrates contained in hot buffer (HA), chelating agents (CH) and diluted alkali (DA) extracts. HA extract contained homogalacturonan with 75% being methyl esterified, and pectic arabinan with traces of pectic galactan, type II arabinogalactan and 1,4-β-glucan. CH extract, recovered with the highest yield (11.0% w/w), was composed mainly of homogalacturonan. DA extract included homogalacturonan with 2% methyl esterification, abundant arabinan and galactans and traces of 1,4-β-glucan. Glucomannan, xylan and xyloglucan represented 66% of the carbohydrates present in the last concentrated alkali extract (CA), the rest being pectic arabinan and galactan. High molecular weight polysaccharides (>102 kDa) were identified in all extracts.

The present study illustrates the development of essential oils (EOs) formulation, and boneless chicken thigh samples were treated with the developed EOs formulation and gamma irradiation to increase the shelf life of treated chicken samples. The binary, tertiary, and quaternary combinations of EOs were developed by the broth dilution method and the fractional inhibitory concentration index. The tertiary combinations of EOs, Thyme + Cannelle + Oregano, showed the best result and exhibited additive (AD) effect against S. enterica, S aureus, and E. coli. The shelf life of the chicken sample increased by 3 days and 8 days when treated by Thyme + Cannelle + Oregano EOs and γ-irradiation, respectively. However, when chicken samples were treated with the combinations of EOs formulations and γ-irradiation, the shelf life of the chicken sample increased by 14 days. The results showed that the combination of EOs treatment with a low dose of γ-irradiation could be used to increase the shelf life of treated food.

The efficiency of laccase-catalyzed protein cross-linking can be impacted by substrate protein structure and competing reactions. In this study, chemical grafting of ferulic acid (FA) on protein surface was applied to modulate the cross-linking of two inflexible globular proteins, lysozyme (LZM) and ovalbumin (OVA). The extent of FA-grafting was positively correlated with protein cross-linking extent, and determined the molecular weight profile and structures of the cross-linked product. While laccase-catalyzed reactions (with or without free FA mediator) did not lead to evident cross-linking of the native proteins, oligomeric (up to 16.4%), polymeric (up to 30.6%) FA-LZMs and oligomeric FA-OVA (5.1–31.1%) were obtained upon the enzymatic treatments. The cross-linking on the grafted FA sites occurred mainly through the formation of 8–5′-noncyclic-dehydro-diferulic linkages. The effects of investigated cross-linking approach on the emulsifying, foaming properties and the immunoglobulin E (IgE) binding capacity of LZM and OVA were also evaluated in relation to the structural properties of cross-linked proteins.

This study aimed to examine the influence of two prebiotics, fructo-oligosaccharides (FOS) and xylo-oligosaccharides (XOS), on probiotic properties (resistance to low pH and bile salt, hydrophobicity and auto-aggregation), metabolites production, and antimicrobial activity of probiotic Lactiplantibacillus (L. pentosus S42 and L. plantarum S61) and Levilactobacillus (L. brevis S27) strains isolated from fermented olive. The results demonstrated the ability of strains to ferment XOS more than FOS as a sole carbon source, resulting in pH reduction. The prebiotics (FOS and XOS) significantly increased (p

The bioactive properties and health-promoting effects of two novel yellow (C09052, C05041) and two brown (Calvi, Bastia) hairless canary seed (Phalaris canariensis L.) cultivars were investigated in comparison to two common cereal grains (wheat and oat). The cereal flours were digested using the standardized INFOGEST in vitro human gastrointestinal digestion model. The three-kilo dalton molecular weight cutoff (3 kDa MWCO) permeate of the generated digestates was assessed in vitro for their antioxidant, chelating, antihypertensive and antidiabetic activities. The results showed no significant differences in studied bioactivities between yellow and brown canary seed cultivars, except for antioxidant activity by the DPPH and chelating Fe2+ assays, where brown cultivars had higher activities. Canary seeds had superior or equivalent antioxidant activity than those from oat and wheat. The anti-hypertensive activity (Angiotensin-converting enzyme (ACE) inhibition) in yellow canary seed cultivars was significantly higher than that of oat and wheat, particularly for C09052 and Calvi varieties. Peptides exhibiting the highest antihypertensive activity from the permeate of the C09052 canary seed variety were further fractionated and identified by mass spectrometry. Forty-six peptides were identified belonging to 18 proteins from the Pooideae subfamily. Fourteen of the parent proteins were homologous to barley proteins. Peptides were analyzed in silico to determine potential bioactivity based on their amino acid composition. All 46 peptides had potential anti-hypertensive and anti-diabetic activities and 20 had potential antioxidant activity, thereby validating the in vitro assay data. Canary seed peptides also exhibited potential antiamnestic, antithrombotic, immunostimulating, opioid and neuro-activity, demonstrating important potential for health promoting effects, particularly against cardiovascular disease.

The synthesis of complex oligosaccharides is desired for their potential as prebiotics, and their role in the pharmaceutical and food industry. Levansucrase (LS, EC 2.4.1.10), a fructosyl-transferase, can catalyze the synthesis of these compounds. LS acquires a fructosyl residue from a donor molecule and performs a non-Lenoir transfer to an acceptor molecule, via &beta, (2&rarr, 6)-glycosidic linkages. Genome mining was used to uncover new LS enzymes with increased transfructosylating activity and wider acceptor promiscuity, with an initial screening revealing five LS enzymes. The product profiles and activities of these enzymes were examined after their incubation with sucrose. Alternate acceptor molecules were also incubated with the enzymes to study their consumption. LSs from Gluconobacter oxydans and Novosphingobium aromaticivorans synthesized fructooligosaccharides (FOSs) with up to 13 units in length. Alignment of their amino acid sequences and substrate docking with homology models identified structural elements causing differences in their product spectra. Raffinose, over sucrose, was the preferred donor molecule for the LS from Vibrio natriegens, N. aromaticivorans, and Paraburkolderia graminis. The LSs examined were found to have wide acceptor promiscuity, utilizing monosaccharides, disaccharides, and two alcohols to a high degree.

The current study focused on the investigation of laccase-catalyzed conjugation of potato protein (PPT) with selected pectic polysaccharides (PPS) and modulation of the conjugation in order to obtain desired functional ingredients. PPS, including sugar beet pectin/arabinan, apple/citrus pectin and potato galactan, were evaluated as substrates in the conjugation reaction-catalyzed by laccases (Trametes versicolor-LacTv, Coriolus hirsutus-LacCh). LacCh exhibited a higher catalytic efficiency than LacTv. The reactivity of PPT/PPS and their ratio were determinants for their heteroconjugation. Both laccases exhibited the highest specificity towards the conjugation of PPT/sugar beet pectin. Predictive models were developed for conjugation efficiency and emulsification performance. The conjugation extent was negatively affected by the protein proportion and the protein proportion/enzyme concentration interaction; while the emulsification performance was positively correlated with the protein proportion and the protein proportion/reaction time interaction. This study contributed to the understanding of laccase-catalyzed conjugation reaction for the controlled synthesis of conjugated-PTT as functional ingredients.

Using disk diffusion assay and broth microdilution, we evaluated the antimicrobial activity of 38 commercially available essential oils (EOs) against 24 food pathogens and spoilers. These including E. coli O157: H7 (3 types), Listeria (3 types), Bacillus (2 types), Salmonella enterica (2 types), Staphylococcus aureus (3 types), Clostridium tyrobutiricum, Pseudomonas aeruginosa, Brochotrix thermosphacta, Campylobacter jejuni, Carnobacterium divergens, Aspergillus (2 types), and Penicillium (4 types). Correlation between EOs’ chemical composition and antimicrobial properties was studied using R software. Moreover, statistical models representing the relationship were generated using Design Expert®. The predictive models identified the chemical attributes of EOs that drive their antimicrobial properties while providing an understanding of their interactions. Thyme (Aldrich, Novotaste), cinnamon (Aliksir, BSA), garlic (Novotaste), Mexican garlic blend N & A (Novotaste), and oregano (BSA) were the strongest antimicrobial. The most sensitive pathogens were P. solitum (MIC of 19.53 ppm) and L. monocytogenes (MIC of 39 ppm). The correlation analysis showed that phenols and aldehydes had the strongest positive effects on the antimicrobial properties followed by the sulfur containing compounds and the esters; while the effects of monoterpenes and ketones were negative. Different sensitivity of food pathogens to chemical families was observed. For instance, phenols and aldehydes exhibited a linear inhibitory effect on L. monocytogenes (LM1045, MIC), while sesquiterpene and ester showed a significant effect on S. aureus (ATCC 6538, MIC). The developed predictive models are expected to predict the antimicrobial properties based on the chemical families of essential oils.

The aim of the present study was to evaluate some technological properties and potential probiotic of 14 Lactobacillus strains isolated from brines of natural fermenting Moroccan Picholine green olive. The brine samples, collected from industrial environments, were analyzed for their Physico-chemical and microbiological properties. The Lactobacillus strains were characterized for their technological and physiological properties. The results obtained showed that the olive brines have an average pH of 4.32, an acidity of 0.61% and chloride contents of 6.42%. LAB and yeasts are the most dominant microorganisms in olive brine samples. The selected Lactobacillus (14 strains) showed low resistance to pH 2 and high resistance to bile salts (up to 2%), with values ranges from 1.98%-4.70% and 63.12%-86.48%, respectively. All the Lactobacillus strains displayed high levels of acidification and can produce β-glucosidase, protease, and cellulase in large amounts. The diacetyl production is detected in five Lactobacillus strains.

Fermented green olives process, occurring in extreme environment characterized by low nutrients and high polyphenols and sodium chloride contents, is dominated by lactic acid bacteria (LAB) and yeasts. The probiotic LAB strains, mostly isolated from various fermented Mediterranean olive varieties and different countries, were Lactobacillus plantarum, Lactobacillus pentosus, Lactobacillus paracasei, Lactobacillus rhamnosus, and Lactobacillus coryniformis. Deep studies on probiotic and safety properties of yeasts need to be developed. Probiotic LAB isolated from fermented olives demonstrated, basing in vitro and in vivo tests, various health beneficial effects, mainly the antibacterial, antifungal, and antiadhesive effects against pathogens, the protective effect against virus infections, anticancer, and metals detoxification activities. Autochthonous or nonautochthonous LAB strains improved the fermentation process, the storage conditions, and the functional property of olives and other food products. The optimization of probiotics selection and application conditions may enhance their health-beneficial effects and technological properties.

Protein concentrates were prepared from defatted barley (Hordeum vulgare L.) flour using alkaline and enzymatic treatments. Milder enzymatic treatments included (i) a bi-enzymatic method involving the use of starch-hydrolyzing enzymes, and (ii) a tri-enzymatic method using the former bi-enzymatic treatment followed by digestion with glucanase. The concentrate obtained through alkaline extraction (AI-BP) was comprised mainly of low molecular weight fractions of proteins. Bi-enzymatic treatment produced a protein concentrate with the highest protein content (49.0%), while those obtained by the tri-enzymatic treatment followed by an isoelectric precipitation step (TEI-BP) gave the highest protein recovery yield (78.3%). In both of the latter concentrates, 35 kDa B-hordeins were the major protein fraction. Divergence in secondary/tertiary structure elements (AI-BP; TEI-BP) was obtained and attributed to the difference in the protein profiles. Further characterization of protein concentrates indicated that they exhibit pseudoplastic behavior. Emulsifying capacity of concentrates was comparable to that of whey protein isolate.