Stéphane Desobry

University of Lorraine | UdL · Laboratoire d'Ingénierie des Biomolécules (LlBio)

Cellulose, in the form of cellulose nanocrystals (CNCs), is a promising biomaterial for stabilizing Pickering emulsions (PEs). PEs are commonly formed using low-frequency ultrasound (LFU) treatment and impact CNC properties. The present study investigated the specific effects of LFU treatment on CNCs’ chemical and physical properties. CNCs were cha...

Two types of alginates, AlgLF and AlgP, were used in this study to produce alginate beads by electro-vibratory extrusion. AlgLF and AlgP exhibited different Mannuronate/Guluronate (M/G) ratios and molecular weights as measured by NMR and SEC-MALS. The calcium chloride concentration was found to have the greatest effect on bead size. Higher concentr...

Spray drying (SD) is extensively used to encapsulate lactic acid bacteria in large-scale industrial applications; however, bacteria combat several harms that reduce their viability. In this study, a novel technique called electrostatic spray drying (ESD) was used to explore the benefits and disadvantages of using electrostatic charge and lower temp...

For the first time on food powders, environmental Atomic Force Microscopy (AFM) was used to probe single particle surface properties in real time by variating relative humidity (RH) and temperature. Low, intermediate, and high dextrose equivalent (DE) maltodextrins values were used as a model matrix. Humidity ramps from 20 to 80% at constant temper...

Cellulose is a promising renewable and biocompatible biopolymer for stabilizing Pickering emulsions (PEs). In the present study, PEs were produced by low-frequency ultrasounds with cellulose nanocrystals (CNCs) and caprylic/capric triglycerides. Phase diagrams allowed to understand mechanisms of formation and long-term stabilization of PEs. Emulsio...

The use of bioresourced packaging materials is an interesting solution for ecological issues. This work aimed to develop novel chitosan-based packaging materials reinforced with hemp fibers (HF). For this purpose, chitosan (CH) films were filled with 15%, 30%, and 50% (w/w) of two kinds of HF: Untreated fibers cut to 1 mm (UHF) and steam exploded f...

The state of the art in the use of chitosan (CS) for preparing particulate carriers for drug delivery applications is reviewed. After evidencing the scientific and commercial potentials of CS, the links between targeted controlled activity, the preparation process and the kinetics of release are detailed, focusing on two types of particulate carrie...

Encapsulation is used in various industries to protect active molecules and control the release of the encapsulated materials. One of the structures that can be obtained using coextrusion encapsulation methods is the core–shell capsule. This review focuses on coextrusion encapsulation applications for the preservation of oils and essential oils, pr...

This paper provides an overview of coextrusion methods for encapsulation. Encapsulation involves the coating or entrapment of a core material such as food ingredients, enzymes, cells, or bioactives. Encapsulation can help compounds add to other matrices, stabilize compounds during storage, or enable controlled delivery. This review explores the pri...

In the current study, native and different fatty acid-esterified waxy maize starches (octanoate, myristoate, and stearoate), followed by an OSA-potato starch (as an industrial emulsifier) were used to prepare sunflower oil-in-water (O/W) emulsion. The effect of emulsifier type and concentration were evaluated on properties of emulsions in terms of...

Husk powder was prepared from seven varieties of walnut fruit and their hulling rate, chemical compounds, and total phenolic contents were evaluated. The apolar and polar extracts were prepared, respectively, from hexane and a hydroethanolic solvent, while qualitative and semi-quantitative analyses were performed by GC/MS and UHPLC-PDA-HRMS/MS. The...

Objective: A combined treatment using both low-frequency (20 kHz) and high-frequency ultrasounds (1.63 MHz) is a promising new process to stabilize emulsions with minimalist formulation. In order to optimize process parameters, a Doehlert experimental design was performed with O/W emulsions, presently used for cosmetic products, composed of water,...

Metal-Chelating Peptides (MCPs), obtained from protein hydrolysates, present various applications in the field of nutrition, pharmacy, cosmetic etc. The separation of MCPs from hydrolysates mixture is challenging, yet, techniques based on peptide-metal ion interactions such as Immobilized Metal Ion Affinity Chromatography (IMAC) seem to be efficien...

In the current study, the physicochemical and emulsifying properties of modified waxy maize starch obtained through a new environmentally friendly method of esterification were evaluated. The starch modification was carried out in NaOH solution with different levels of octanoyl, myristoyl, and stearoyl chlorides. Increasing the fatty acid chlorides...

This review is primarily focused on the comparison of three emerging techniques: electrospraying, nano spray drying, and electrostatic spray drying techniques. There are persistent advances to develop efficient drying technique for sensitive bioactives and to overcome their hurdles. These processes involve electrostatic forces as a promising factor...

In this study, a novel approach was investigated to improve the stability of anthocyanin compounds (AC) by encapsulating them in nanoliposomes resulting from rapeseed lecithin alongside chitosan coating. The results indicate that the particle size, electrophoretic mobility, encapsulation efficiency, and membrane fluidity of nanoliposomes containing...

Dripping coextrusion technology was used to produce core-shell capsules (olive oil/alginate). Mathematical models were developed to study isolated, and interactions impacts of calcium chloride concentration (37.5–187.5 g. L⁻¹), alginate and oil total feed rate (40–108 g min⁻¹), and dripping height (7–15 cm) on capsules characteristics. Therefore, c...

Emulsions are multiphasic systems composed of at least two immiscible phases. Emulsion formulation can be made by numerous processes such as low-frequency ultrasounds, high-pressure homogenization, microfluidization, as well as membrane emulsification. These processes often need emulsifiers’ presence to help formulate emulsions and to stabilize the...

Reconstitution kinetics of three maltodextrins powders with different dextrose-equivalent (DE) values (low, intermediate, high DE) were evaluated under the glassy and rubbery states. Reconstitution times were found mostly shear rate of agitation in water and DE dependent in the glassy state, with shorter reconstitution times for high shear rates an...

Oil-alginate capsules were produced by annular jet breaking coextrusion. Effects of alginate flow rate (30-50 mL/min), oil flow rate (4-18 mL/min), applied frequency (80-200 Hz), calcium concentration (1.5-50 g/L) and alginate solution age (24-72 h) and their interactions, on capsules shape and encapsulation payload were studied using response surf...

Reconstitution of six fruit powders, compacted and non-compacted, were studied. It appears that powder reconstitution behavior under sheared conditions was significantly different with regards to the water activity (aw). At low aw, the powders exhibit a glassy state with a stiff surface measured by Atomic Force Microscopy and porous/angular shapes...

Spherification methods to produce particles of millimetric size are detailed in this review, especially for encapsulation purpose and using alginate. Therefore, alginate properties and factors impacting its gelation, counting its structure and experimental conditions such as pH, temperature, crosslinker concentration, residence time and ionic stren...

In the present study, nanoliposomes composed of rapeseed lecithin were used for the encapsulation of anthocyanin compounds (AC). The nanoliposomes were prepared using hydration and ultrasound combined method, and the effect of AC concentration (4.5, 6.75, 9% w/w) on the characteristics of nanoliposomes including particle size, polydispersity index...

Production of iron-chelating peptides from protein hydrolysates requires robust and adequate screening methods to optimize their purification and subsequently valorize their potential antioxidant properties. An original methodology was developed for direct and sensitive screening of iron(II)-chelating peptides based on ion-pair reverse phase liquid...

Minerals are essential to different biological processes in living beings. Likewise, free transition metals such as copper and iron promote the formation of reactive oxygen species (ROSs). However, metal-binding peptides obtained by enzymatic hydrolysis of proteins or synthesized by solid-phase peptide synthesis avoid ROS formation catalyzed by fre...

In this study, preservation of spirulina using the new pressurised cryogenic nitrogen technology (PCN) was compared to classical methods used in laboratories and industry. Spirulina morphology was better preserved by PCN compared to unpressurised cryogeny and classical freezing at −20 °C that led to cells fragmentation. A 25% loss of Phycocyanin‐C...

In the present review, natural and non-toxic particles made of micro/nanocellulose were specifically targeted as stabilizers of emulsions located at dispersed and continuous phases interfaces (called Pickering Emulsions, PEs). PEs are biphasic systems stabilized by solid particles with a recent interest in food and cosmetic domains. PEs have been m...

In this study, the proximate composition and physicochemical analyses were carried out on the larva and extracted oil of Rhynchophorus phoenicis. The results showed that the larva contained 0% moisture, 24% crude protein, 6.3% ash, 68.5% fat and 1.2% carbohydrate. The larvas were found to be good sources of minerals. Sodium (832.59±0.5 mg/100g) was...

Nanoliposomes are widely used as delivery vehicles for active compounds. Nanoliposomes from rapeseed phospholipids were incorporated into interpenetrating polymer network (IPN) hydrogels of gelatin methacryloyl (GelMA) and alginate. The multiscale physicochemical properties of the hydrogels are studied both on the surface and through the thickness...

The PAOT Skin Technology® is a device that measures the total activity oxidizing biological tissues such as skin and plants. PAOT Skin Technology® makes it possible to obtain measurements directly on the surface of the tissue, thanks to contact electrodes (identical to those used in cardiology). The PAOT Technology® Skin is designed to measure the...

The objective of the study is to compare the composition of nutrients on two cultivars of voandzou seeds. The seeds of voandzou we studied come from the locality of Nkamba South of the DR Congo and in the town of Djambala precisely in the North of Congo Brazzaville. Biochemical and physicochemical seeds characteristics were evaluated to determine t...

Curcumin is a natural polyphenol that has strong antioxidant, anti-inflammatory and anti-carcinogenic properties, however, it is sensitive to light, oxygen and heat, and also presents very low solubility in water. Several studies have focused on curcumin preservation and bioavailability due to its health importance, especially by encapsulation. Mil...

We aimed to study the effect of conjugation with gum Arabic (GA) by Maillard reaction in aqueous solution on the structural properties of Canola protein isolate (CPI). First, the grafting of GA to CPI through Maillard reaction was confirmed by examination of the Fourier transform infrared spectra. The results showed that the thermal stability of CP...

Emulsion-based delivery systems have been developed to increase the topical bioavailability of lipophilic active compounds within skin membrane. The aim was to develop nanoemulsion from natural sources (rapeseed oil) with the same sources of pure phospholipids (lecithin) rich on mono and polyunsaturated fatty acids for encapsulation of hydrophobic...

Novel bioactive films were developed from the incorporation of Lactococcus lactis into polysaccharide films. Two different biopolymers were tested: cellulose derivative (hydroxylpropylmethylcellulose (HPMC)) and corn starch. Lactic acid bacteria (LAB) free or previously encapsulated in alginate-pectin composite hydrogel microbeads were added direct...

Protein aggregates can be formed by heating globular proteins above the thermal denaturation of the proteins. These aggregates can be used as delivery systems or to modulate the physicochemical and sensory properties of food products. In this study, the effects of heat treatment (15 min at 80 °C), pH adjustment (between 4 and 9), aging at different...

The aim of this work is the study of the influence of different drying methods (open air, oven) on the kinetics of drying process of cassava (Manihotglaziovii) leaves. Regardless of temperature and the method of drying, the change in mass follows an identical development, the curves of the moisture content based on the time have an identical look....

Transgenic hairy roots of Datura spp. established using strain A4 of Agrobacterium rhizogenes are genetically stable and produce high levels of tropane alkaloids. To increase biomass and tropane alkaloid content of this plant tissue, four Pseudomonas strains, Pseudomonas fluorescens P64, P66, C7R12 and P. putida PP01, were assayed as biotic elicito...

Given the importance of the extracellular medium during tissue formation, it was wise to develop an artificial structure that mimics the extracellular matrix while having improved physico-chemical properties. That is why the choice was focused on gelatin methacryloyl (GelMA), an inexpensive biocompatible hydrogel. Physicochemical and mechanical pro...

This study evaluated the influence of spouted bed drying temperature and maltodextrin dextrose equivalent on the probiotic microbial survival during drying and storage period and on physicochemical properties of fermented probiotic orange juice in powder. Probiotic orange juice was spouted bed dried at 60, 70, 80 and 90. °C using maltodextrin with...

Cette présentation par poster a montré les premiers résultast concernant une méthode de criblage rapide par IMAC-MS de peptides chélateurs de métaux pour leurs propriéties antioxydantes.

Matrix composition plays a crucial role in the controlled release of viable and functional bacteria in the intestine. Imaging tools such as electronic and confocal microscopies were used in this work to investigate the influence of matrix composition on matrix integrity and porosity, bacterial spatial distribution and viability during simulated in...

The aim of this study was to produce covalently attached conjugate between canola protein isolate (CPI) and gum Arabic (GA) in aqueous solutions via the Maillard reaction at 90 °C in a model system consisting of 2% CPI and 1, 2 or 4% GA. Upon decreasing of free amino group content in the glycosylated CPI to 72%, a new band near the loading end of s...

In this research, the improvement of emulsifying properties of chemically modified canola protein isolate (CPI) with gum Arabic (GA) through Maillard reaction under natural pH at 90 °C was investigated. The stability, rheology and morphology of oil-in-water emulsions stabilized by conjugate of two biopolymers were evaluated by determination of drop...

Application of nanobiotechnology to improve the controlled release of drugs or functional agents is widely anticipated to transform the biomedical, pharmaceutical and food safety trends. The purpose of the present study was to evaluate and compare the release rates of fluorescently labeled antimicrobial peptide nisin (lantibiotic/biopreservative) f...

Drying of probiotic fruit juice can be a good alternative for new probiotic foodstuff production since most probiotic foods are dairy-based products, which are not suitable for people with galactosemia, lactose intolerance or allergy to milk protein. Thus, the aim of this study was to evaluate the influence of spray and spouted bed drying and feed...

Enzymatic modification of chitosan particles by the ferulic acid (FA) and ethyl ferulate (EF) oxidation products using Myceliophtora thermophyla laccase in mild conditions (pH 7.5, 30 °C in aqueous medium) was investigated. The chitosan derivatives showed an increase of degree of acetylation (DA), molecular mass (MM) and viscosity in comparison wit...

Abstract Context: Catharanthus roseus (L.) G. Don (Apocynaceae) is still one of the most important sources of terpene indole alkaloids including anticancer and hypertensive drugs as vincristine and vinblastine. These final compounds have complex pathway and many enzymes are involved in their biosynthesis. Indeed, ajmalicine and catharanthine are im...

To enhance physico-chemical properties of alginate liquid-core capsules, shellac was incorporated into the membrane (composite capsules) or as an additional external layer (coated capsules). The influence of pH, coating time, shellac concentration and preparation mechanism (acid or calcium precipitation) were investigated. Results showed that shell...

Hypothesis: To enhance physicochemical properties of alginate aqueous-core capsules, conventional strategies were focused in literature on designing composite and coated capsules. In the present study, own effect of liquid-core composition on mechanical and release properties was investigated. Experiments: Capsules were prepared by dripping a Ca...

Alginate/pectin hydrogel microspheres were prepared by extrusion based on a vibrating technology to encapsulate bacteriocin-producing lactic acid bacteria. Effects of both alginate/pectin (A/P) biopolymers ratio and physiological state of Lactococcus lactis subsp. lactis (exponential phase, stationary phase) were examined for nisin release properti...

In this study, cellulose foams incorporated with surface-modified montmorillonite (SM-MMT) were prepared following NaOH dissolution and regeneration into water and ethanol. According to the SEM images, the type of coagulating agent significantly affected the morphological properties of composite foams. The crystalline parameters were evaluated usin...

Aqueous-core microcapsules with sodium alginate (SA) hydrogel in membrane and xanthan gum (XG) in core were prepared using ionotropic gelation method to encapsulate bacteriocin-producing lactic acid bacteria (LAB). In this study LAB were immobilized in microcapsule membrane. XG was applied to reinforce SA microcapsules. Molecular interaction betwee...

4th TERMIS World Congress, Boston, MA, SEP 08-11, 2015

Emulsifier-free-emulsions developed with new emulsification process by high frequency ultrasound (HFU) was used for CoQ10 vectorization and compared with CoQ10 emulsions containing natural emulsifier (rapeseed lecithin) manufactured with same process and with low frequency ultrasounds coupled with high pressure emulsification (LFU+HPH). Physico-che...

In this work, rheological properties of cellulose solution incorporated with different concentration of surface-modified montmorillonite (SM-MMT) were investigated. Thermal behavior analyses of cellulose solutions were performed using rheological tests; including determination of various factors to estimate the gelation temperature and time. The re...

In the present study, characteristics of seeds and oil extracted by soxhlet with hexane from Manga groundnut (Arachis hypogea) are evaluated. The percentage composition of the Manga groundnut seeds is: lipid content (47.43±1.6%), protein content (32.64±0.26%) and Total carbohydrates (17.56±1.33%), moisture (7.58±0.86) and ash (5.67±0.98). The major...

Some quality characteristics of seed oil extracted from Kumu; (Bombax aquaticum ) or "white peanut" harvest at Nkamba (DR Congo) were investigated. Herein, Kumu was chemically characterized regarding nutritional value, fatty acids, crude fat and chemicals indices. Furthermore, viscosity, absorptivity at 232 and 270 nm, color and DSC profil were eva...