Publications by authors named "Hanitra Rabesona"

9 Publications

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digestion of food grade TiO (E171) and TiO nanoparticles: physicochemical characterization and impact on the activity of digestive enzymes.

Food Funct 2021 Jul;12(13):5975-5988

INRAE, UR1268 Biopolymères Interactions Assemblages, 44300 Nantes, France.

Titanium dioxide is a food additive that has raised some concerns for humans due to the presence of nanoparticles. We were interested in knowing the fate of TiO2 particles in the gastro-intestinal tract and their potential effect on digestive enzymes. For this purpose, we analysed the behaviour of two different food grade TiO2 samples (E171) and one nano-sized TiO2 sample (P25) through a standardized static in vitro digestion protocol simulating the oral, gastric and intestinal phases with appropriate juices including enzymes. Both E171 and P25 TiO2 particles remained intact in the digestive fluids but formed large agglomerates, and especially in the intestinal fluid where up to 500 μm sized particles have been identified. The formation of these agglomerates is mediated by the adsorption of mainly α-amylase and divalent cations. Pepsin was also identified to adsorb onto TiO2 particles but only in the case of silica-covered E171. In the salivary conditions, TiO2 exerted an inhibitory action on the enzymatic activity of α-amylase. The activity was reduced by a factor dependent on enzyme concentrations (up to 34% at 1 mg mL-1) but this inhibitory effect was reduced to hardly 10% in the intestinal fluid. In the gastric phase, pepsin was not affected by any form of TiO2. Our results hint that food grade TiO2 has a limited impact on the global digestion of carbohydrates and proteins. However, the reduced activity specifically observed in the oral phase deserves deeper investigation to prevent any adverse health effects related to the slowdown of carbohydrate metabolism.
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http://dx.doi.org/10.1039/d1fo00499aDOI Listing
July 2021

Role of the bolus degree of structure on the protein digestibility during in vitro digestion of a pea protein-fortified sponge cake chewed by elderly.

J Texture Stud 2020 02 3;51(1):134-143. Epub 2019 Nov 3.

Centre des Sciences du Goût et de l'Alimentation, AgroSup Dijon, CNRS, INRA, Université Bourgogne Franche-Comté, Dijon, France.

This study investigated the digestibility of proteins in a pea protein-fortified sponge cake, as well as the impact of the degree of structure of the bolus produced by elderly subjects on the digestibility of proteins by combining ex vivo and in vitro approaches via the standardized protocol INFOGEST. The sponge cakes were consumed by a group of 20 elderly subjects with contrasting physiology, their boli were recovered just before swallowing, and their apparent viscosity was measured to delineate the bolus degree of structure. According to this criterion, two pools were formed with boli from subjects selected at the extremes: low viscosity and high viscosity, with apparent viscosity values (at 120 s ) of 124 ± 18 and 208 ± 19 Pa s, respectively. The sponge cakes and the two pools underwent in vitro digestion. Protein hydrolysis kinetics was followed by measuring the released primary amino groups (NH ) and by sodium-dodecyl-sulfate polyacrylamide gel electrophoresis at different time points. For all samples, the representative bands of pea proteins disappear gradually during digestion, accompanied by the appearance of bands indicating the presence of proteins with M  < 15 kDa. In addition, the NH concentrations increase over time and do not differ between sponge cake and pea protein isolate. Moreover, the degree of structure of the food bolus has no significant effect on the concentration of NH released. These results showed that pea proteins in a fortified sponge cake are bioaccessible under standardized conditions and that the degree of structure of the bolus did not influence protein digestibility for these foods.
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http://dx.doi.org/10.1111/jtxs.12486DOI Listing
February 2020

Combined microwave processing and enzymatic proteolysis of bovine whey proteins: the impact on bovine β-lactoglobulin allergenicity.

J Food Sci Technol 2019 Jan 8;56(1):177-186. Epub 2018 Nov 8.

UR 1268 Biopolymères Interactions Assemblages, Équipe Fonctions et Interactions des Protéines, INRA, 44316 Nantes Cedex 03, France.

The main aim of this study was to develop a continuous microwave treatment system of whey proteins and then apply this process at 37 °C, 50 °C, 65 °C and 70 °C to achieve pepsinolysis and produce extensively hydrolysed bovine whey protein hydrolysates with low allergenic properties. The microwave process was compared to a conventional thermal treatment with similar temperature set points. Both processes were deeply analysed in terms of the thermal kinetics and operating conditions. The pepsin hydrolysates obtained by the continuous microwave treatment and conventional heating were characterized by SDS-PAGE and RP-HPLC. The allergenicity of the whey protein hydrolysates was explored using a human IgE sensitized rat basophil leukaemia cell assay. The results indicate that extensively hydrolysed whey protein hydrolysates were obtained by microwave only at 65 °C and in a shorter time compared with the conventional thermal treatment. In the same temperature conditions under conventional heating, β-lactoglobulin was resistant to pepsinolysis, and 37% of it remained intact. As demonstrated by an in vitro degranulation assay using specific human IgE-sensitized rat basophils, the extensively hydrolysed whey protein obtained by microwave showed maximum degranulation values of 6.53% compared to those of the native whey protein isolate (45.97%) and hence elicited no more allergenic reactions in basophils. This work emphasizes the potential industrial use of microwave heating specific to milk protein processing to reduce their allergenicity and improve their end-use properties.
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http://dx.doi.org/10.1007/s13197-018-3471-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6342792PMC
January 2019

Inhibition of Staphylococcus aureus in vitro by bacteriocinogenic Lactococcus lactis KTH0-1S isolated from Thai fermented shrimp (Kung-som) and safety evaluation.

Arch Microbiol 2017 May 5;199(4):551-562. Epub 2017 Jan 5.

UR 1268 Biopolymères Interactions Assemblages, Équipe Fonctions et Interactions des Protéines, INRA, 44316, Nantes Cedex 03, France.

Lactococcus lactis KTH0-1S isolated from Thai traditional fermented shrimp (Kung-som) is able to produce heat-stable bacteriocin and inhibits food spoilage bacteria and food-borne pathogens. The inhibitory effect of bacteriocin remained intact after treatment with different pHs and after heating, but was sensitive to some proteolytic enzymes. Addition of bacteriocin KTH0-1S to Staphylococcus aureus cultures decreased viable cell counts by 2.8 log CFU/ml, demonstrating a bactericidal mode of action. Furthermore, the growth of S. aureus decreased significantly after 12-h co-cultivation with bacteriocinogenic strain. The molecular mass of bacteriocin KTH0-1S was found to be 3.346 kDa after ammonium sulfate precipitation, reversed phase (C Sep-Pak), cation-exchange chromatography, RP-HPLC on C column and mass spectrometry (MS/MS) analysis. Bacteriocin KTH0-1S was identified as nisin Z using PCR amplification and sequencing. The majority of tested virulence factors were absent, confirming the safety. Evidenced inhibitory effect of this strain, the absence of virulence factors creates the possibility for its application as protective culture to inhibit pathogenic bacteria in the several fermented seafood products.
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http://dx.doi.org/10.1007/s00203-016-1324-3DOI Listing
May 2017

Interactions of β-lactoglobulin variants A and B with Vitamin A. Competitive binding of retinoids and carotenoids.

J Agric Food Chem 2013 May 19;61(17):4114-9. Epub 2013 Apr 19.

UR 1268, INRA Biopolymères Interactions Assemblages-équipe Fonctions et Interactions des Protéines, rue de la Géraudière, B.P. 71627, 44316 Nantes Cedex 03, France.

β-Lactoglobulin (β-Lg) is the major whey protein of bovine milk present at a concentration of 2-3 g L(-1). Its biological role is still not well-known. However, many studies have suggested that β-Lg may play either nutritional or specific transporter role. The high affinity of β-Lg for retinol and other retinoids was reported. The results of interaction studies of β-Lg with carotenoids, that is, β-carotene, β-cryptoxanthin, and α-carotene, which display similar structures are reported in this study. The affinities of β-Lg for binding of retinoids and carotenoids were compared, providing more information about the binding site(s) of these molecules by β-Lg. Interactions were followed by the measurements of quenching of β-Lg tryptophan fluorescence and retinol fluorescence. The obtained results indicate that carotenoids are bound by β-Lg with high affinity of the order of 10(-8) M. Measurement of retinol competition with carotenoids for binding by β-Lg suggests that the binding of these two ligands occurs at two different sites of β-Lg.
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http://dx.doi.org/10.1021/jf400711dDOI Listing
May 2013

Antimicrobial and antifungal activities of Lactobacillus curvatus strain isolated from homemade Azerbaijani cheese.

Anaerobe 2013 Apr 26;20:42-9. Epub 2013 Jan 26.

UR 1268, INRA Biopolymères Interactions Assemblages - Equipe FIP, B.P. 71627, 44316 Nantes Cedex 03, France.

The aims of this study were to characterize inhibitory activity spectra, some probiotic properties and safety of Lactobacillus curvatus A61 for its future application in production of fermented foods. The studied strain was isolated from traditional homemade cheese manufactured in Azerbaijan. The cell-free supernatant of culture of Lb. curvatus A61 inhibited the growth of tested LAB, as well as of Listeria monocytogenes and Bacillus cereus strains. The strain presented antifungal activity and inhibited the growth of Cladosporium and Fusarium ssp. during co-cultivation on agar media. PCR amplification with specific primers revealed the presence of curvacin A encoding gene in Lb. curvatus A61. Bacteriocin produced by the studied strain was heat stable and active in a broad pH range, and in the presence of Triton X-20, Triton X-80, Triton X-100, β-mercaptoethanol, Na-EDTA, SDS and NaCl. The mode of action of bacteriocin against selected indicator strains was found to be bacteriostatic. Lb. curvatus A61 was resistant to physiological concentrations of bile salts and showed high auto-aggregation ability, as well as co-aggregation ability with pathogenic L. monocytogenes strains. It was sensitive to chloramphenicol, penicillin, tetracycline, ciprofloxacin and vancomycin, but resistant to ampicillin and gentamicin.
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http://dx.doi.org/10.1016/j.anaerobe.2013.01.003DOI Listing
April 2013

Proteolytic action of Lactobacillus delbrueckii subsp. bulgaricus CRL 656 reduces antigenic response to bovine β-lactoglobulin.

Food Chem 2011 Jul 9;127(2):487-92. Epub 2011 Jan 9.

Centro de Referencia para Lactobacilos (CERELA)-CONICET, Chacabuco 145, 4000 San Miguel de Tucumán, Argentina.

The whey protein β-lactoglobulin (BLG) is highly allergenic. Lactic acid bacteria can degrade milk proteins. The capacity of Lactobacillus delbrueckii subsp. bulgaricus CRL 656 to hydrolyse the major BLG epitopes (V41-K60; Y102-R124; L149-I162) and decrease their recognition by IgE of allergic patients was evaluated. The intensity of BLG degradation was analysed by Tricine SDS-PAGE and RP-HPLC. Peptides released were identified by LC-MS/MS and the hydrolysates were tested for their capacity to inhibit IgE binding by ELISA test. L. delbrueckii subsp. bulgaricus CRL 656 degraded BLG (35%, 8h). The sequence analysis of the released peptides indicated that this strain degraded three main BLG epitopes. BLG-positive sera (3-5year old children) were used for testing IgE binding inhibition of BLG hydrolysates from the Lactobacillus strain. The hydrolysates were less immuno-reactive (32%) than the heated BLG. L. delbrueckii subsp. bulgaricus CRL 656 could be used for developing hypoallergenic dairy products.
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http://dx.doi.org/10.1016/j.foodchem.2011.01.029DOI Listing
July 2011

Proteolysis by Lactobacillus fermentum IFO3956 isolated from Egyptian milk products decreases immuno-reactivity of αS1-casein.

J Dairy Res 2011 May 9;78(2):203-10. Epub 2011 Mar 9.

UR 1268 Biopolymères Interactions Assemblages, INRA, F-44300 Nantes.

Proteinase activity of Lactobacillus fermentum IFO3956 cells was higher when they were grown on milk-based media than on 10% reconstituted skim milk. The lowest protease activity was observed when cells were grown on milk-free media. The extraction of milk-induced cell-bound proteases from Lb. fermentum IFO3956 was most efficient using 1% Tween 80 while the use of 1% SDS inhibited all proteolytic activity. Two bands of ∼35 and >100 kDa were observed by zymogram, indicating that proteolytic activity corresponded to the presence of at least two types of enzymes or two molecular forms of one enzyme. Mass spectrometry analyses of αS1-casein hydrolysates detected 24 peptides with sizes ranging from 5 to 36 amino acids, including 9 phosphorylated peptides, resulting from the fermentation of Lb. fermentum IFO3956 of αS1-casein. Most of the identified peptides originated from the N-terminal portion of αS1-casein. The studied bacterial strain could hydrolyze αS1-casein in many sites including the epitopes triggering the allergic reactions against αS1-casein e.g. at the positions 23, 30, 41, 71, 91, 98, 126, 179. After hydrolysis of αS1-casein with Lb. fermentum IFO3956 the recognition and the binding of this casein to IgE from the pooled sera of 18 patients with cow's milk allergy was significantly reduced.
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http://dx.doi.org/10.1017/S0022029911000100DOI Listing
May 2011

Effects of heating and glycation of beta-lactoglobulin on its recognition by IgE of sera from cow milk allergy patients.

J Agric Food Chem 2009 Jun;57(11):4974-82

UR 1268 Biopolymeres Interactions Assemblages, INRA, Nantes, France.

beta-Lactoglobulin (beta-LG) is one of the cow's major milk proteins and the most abundant whey protein. This globular protein of about 18 kDa is folded, forming a beta-barrel (or calyx) structure. This structure is stabilized by two disulfide bonds and can be altered by heating above 65 degrees C. beta-LG is also one of the major allergens in milk. Heating is one of the most common technologic treatments applied during many milk transformations. During heating in the presence of reducing sugars, beta-LG is also submitted to the Maillard reaction, which at the first stage consists of the covalent fixation of sugars on the epsilon-amino groups of lysyl residues. The following steps are condensation and polymerization reactions leading to the formation of melanoidins (brown pigments). Despite the frequency of use of heating during milk transformation, the effects of heat-induced denaturation and of glycation of beta-LG on its recognition by IgE from cow's milk allergy (CMA) patients are not fully understood. The objectives of our work were to evaluate the effect of heat-induced denaturation of bovine beta-LG on binding of IgE from CMA patients and to determine the effect of moderate glycation on the degree of recognition by IgE. We showed that heat-induced denaturation (loss of tertiary and secondary structures) of beta-LG is associated with weaker binding of IgE from CMA patients. It was also shown that moderate glycation of beta-LG in early stages of Maillard reaction has only a small effect on its recognition by IgE, whereas a high degree of glycation has a clear "masking" effect on the recognition of epitopes. This demonstrates the importance of epsilon-amino groups of lysines in the definition of epitopes recognized by IgE.
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http://dx.doi.org/10.1021/jf804038tDOI Listing
June 2009
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