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Polylactic acid (PLA), although has many interesting physicochemical characteristics, the strong hydrophobicity and a lack of antibacterial activity restricting its widespread application in the medical sector. In a view of addressing some of the limitations of PLA, the current study aimed to test the antibacterial efficacy of active metal-doped bioceramic/PLA composite formed by the fused deposition manufacturing (FDM) technique. For the testing, we prepared polyvinyl alcohol (PVA) bound silver-hydroxyapatite (Ag-HAp) composite and further applied as a low-temperature coating onto the PLA scaffold designed for the appropriate cell development, differentiation, and bio-mineral establishment. From the analysis, we revealed that the larger surface area of three-dimensional (3D) printed composite material having the matrix porosity makes it a perfect biocompatible material with no loss to its mechanical potency. The HAp/PLA and Ag-HAp/PLA composites were tested for the hemocompatibility, and antibacterial activity (gram-positive and gram-negative bacteria). Further, the mechanical property of the Ag-HAp/PLA scaffold was tested. The results demonstrated that the Ag-HAp/PLA composite offers the biocompatibility and antibacterial ability and therefore can serve as the potential bone implant material. (C) 2020 The Author(s). Published by Elsevier B.V.

Botrytis cinerea is a necrotrophic fungus that affects various plant species. Chemical control is a necessity and as much as possible, eco-friendly conditions and bioresources to obtain these chemicals should be used. In this context, a series of products was obtained from salicylaldehyde using zinc as a powerful reagent and tested for antifungal activity against Botrytis cinerea

Given a graph, a geodetic set (resp. edge geodetic set) is a subset of its vertices such that every vertex (resp. edge) of the graph is on a shortest path between two vertices of the subset. A strong geodetic set is a subset S of vertices and a choice of a shortest path for every pair of vertices of S such that every vertex is on one of these shortest paths. The geodetic number (resp. edge geodetic number) of a graph is the minimum size of a geodetic set (resp. edge geodetic set) and the strong geodetic number is the minimum size of a strong geodetic set. We first prove that, given a subset of vertices, it is \(\mathcal {NP}\)-hard to determine whether it is a strong geodesic set. Therefore, it seems natural to study the problem of maximizing the number of covered vertices by a choice of a shortest path for every pair of a provided subset of vertices. We provide a tight 2-approximation algorithm to solve this problem. Then, we show that there is no Open image in new window polynomial-time approximation algorithm for edge geodetic number and strong geodetic number on subcubic bipartite graphs with arbitrarily high girth. We also prove that geodetic number and edge geodetic number are both LOG-\(\mathcal {APX}\)-hard, even on subcubic bipartite graphs with arbitrarily high girth. Finally, we disprove a conjecture of Irsis and Konvalinka by proving that the strong geodetic number can be computed in polynomial time in complete multipartite graphs.

The stability of cosmetic products in terms of microbial safety or oxidation is a major challenge when faced with consumer's expectations for less controversial compounds used in their formulation. In this context, we present new vanillin derivatives synthesized in a two steps one-pot process. The synthesis was based on the reductive amination reaction between vanillin and a selected panel of amines with different structural units such as alkyl chains, halogens and aromatics. The different molecules were designed to bring a better understanding of the structure-preservative activity relationships in vanillin-based molecules. Most compounds exhibited strong antioxidant activities in DPPH, ABTS and FRAP assays. The antibacterial and antifungal properties were evaluated on several strains known to be responsible for the contamination of cosmetic products. Some of these vanillin compounds derived with a p-ethylaniline (2c), with a p-butylaniline (2d), with a p-hexylaniline (2e) and a p-iodoaniline (3b) showed a promising level of antibacterial activity against Bacillus subtilis and Micrococcus luteus. In particular, 2d was very active against most of the tested bacterial and fungal strains and showed very promising antibacterial and antifungal capabilities while displaying among the highest antioxidant capacity and no cytotoxic effect on human fibroblasts. We investigated if a correlation between the hydrophobicity and biological activities of the compounds could be established and we highlighted that the presence of aliphatic chains grafted on the aromatic amine ring is associated to the highest antimicrobial activities. The structure-activity relationships highlighted in this study allow paving the way for future applications of these compounds in cosmetics as alternative to controversial molecules.

International audience; Azobenzenes are photochromic molecules that possess a large range of applications. Their syntheses are usually simple and fast, and their purifications can be easy to perform. Oligosaccharide is also a wide family of biopolymer constituted of linear chain of saccharides. It can be extracted from biomass, as for cellulose, being the principal constituent of plant cell wall, or it can be enzymatically produced as for cyclodextrins, having properties not far from cellulose. Combining these two materials families can afford interesting applications such as controlled drug-release systems, photochromic liquid crystals, photoresponsive films or even fluorescent indicators. This review will compile the different syntheses of azo-dyes-grafted oligosaccharides, and will show their various applications.

Among the photochromes superfamily, azobenzene subgroup is the most extensively produced and used scaffold for many applications. However, the emergence of MDR (multi-drug resistant) bacterial strains brought to light the urgent need of efficient antimicrobial molecules. In that context, this review aims to compile the different approaches coupling azobenzene and antimicrobial activity. Thus, this paper will focus on mono-azo, bis-azo and tetra-azo dyes, surfactant-azo molecules, organometallic azo dyes and photochromic azo materials with antimicrobial activities.

International audience; We introduce a new variable selection method, called SgenoLasso, that handles extreme data. Our method relies on the construction of a specific statistical test, a transformation of the data and by the knowledge of the correlation between regressors. It is appropriate in genomics since once the genetic map has been built, the correlation is perfectly known. This new technique is inspired by stochastic processes arising from statistical genetics. We prove that the signal to noise ratio is largely increased by considering the extremes. Our approach and existing methods are compared on simulated and real data, and the results point to the validity of our approach.; . Nous introduisons une nouvelle méthode de selection de variables, nommée SgenoLasso, qui prend en compte les données extrêmes. Notre méthode est basée sur la construction d'un test statistique spécifique, une transformation des données et par la connaissance de la corrélation entre régresseurs. Cela s'avère approprié en génomique car une fois la carte génétique construite, cette corrélation est parfaitement connue. Cette nouvelle technique est inspirée des processus stochastiques en provenance de la statistique génétique. Nous prouvons que le rapport signal bruit est largement augmenté en considérant les extrêmes. Notre approche ainsi que les méthodes existantes sont comparées sur données simulées et réelles. Ceci valide notre nouvelle approche.

International audience; The production of pigments using single cell microorganisms is gaining traction as a sustainable alternative to conventional syntheses, which rely, in no negligible proportions, on petrochemicals. In addition to depending on petroleum, these syntheses involved the use of toxic organic solvents, which may be inadequately disposed of across a range of industries, thus compounding the deleterious effects of fossil fuel exploitation. Literature suggests that notable research efforts in the area of sustainable pigment production using single cell microorganisms are focused on the production of pigments coveted for their interesting qualities, which transcend their mere capacity to dye various fabrics both natural and synthetic. As interest in sustainable pigment biosynthesis grows, the need to devise effective and efficient cell disruption processes becomes more pressing given that the viability of pigment biosynthesis is not only dependent on microorganisms’ yield in terms of production, but also on researchers’ ability to recover them. This review chiefly reports findings as to mechanical cell disruption methods, used individually or in various combinations, and their aptitude to recover biosynthetic pigments.

Steviol glycosides are natural sweeteners extracted from Stevia rebaudiana Bertoni leaves. Conventional extraction processes are currently used for the industrial production of these molecules, which involve the application of chemical and physical treatments that consume a significant amount of energy. Increasing the extraction yield and purity of the product, along with reducing the environmental impact of the solvents used and the energy consumed, require the development of novel extraction processes. Emerging technologies such as electrotechnologies (e.g., pulsed electric fields, high-voltage electrical discharges), ultrasound-assisted extraction, microwave-assisted extraction, and pressurized fluids, have shown great potential in replacing the conventional processes for the recovery of steviol glycosides from S. rebaudiona leaves. These technologies are presented in this chapter and their efficiency in ensuring a more cost-effective availability of steviol glycosides is discussed.

Pyrolysis of pine wood sawdust was carried out using microwave-heating technology in the presence of activated carbon (AC). Experimental conditions were of 20 min processing time, 10 wt.% of AC, and a microwave power varying from 100 to 800 W. The results obtained showed that the microwave absorber allowed increasing the bio-oil yield up to 2 folds by reducing the charcoal fraction. The maximum temperature reached was 505 &deg, C at 800 W. The higher heating values (HHV) of the solid residues ranged from 17.6 to 30.3 MJ/kg. The highest HHV was obtained for the sample heated at 800 W with 10 wt.% of AC, which was 33% higher than the non-charged sample heated at the same power. Furthermore, the addition of AC allowed showing the probable catalytic effect of the AC in the charged sample pyrolysis bio-oils.

International audience; Lactic acid bacteria (LAB) have a long history of applications in the food industry for fermentation and preservation. This feature is due to their metabolic products that can improve the nutritional and sensory characteristics of foods as well as their antimicrobial compounds that contribute to extend the shelf life of food products. Some emerging technologies including pulsed electric fields (PEF), power ultrasound (US), high-pressure processing (HPP), ultraviolet (UV), and microwave (MW) have attracted great attention for their implementation in the food industry as mild processing technologies. They have the advantage of efficiently inactivating the microorganisms, along with maintaining the fresh attributes of the food products. When applied at a sub-lethal level, these technologies present the potential to enhance several processes, such as improved microbial growth and fermentation conditions, as well as modified metabolic properties of LAB. This review covers the characteristics of LAB and their applications in the food industry. It discusses the impacts of emerging technologies on these microorganisms, with a special focus on microbial inactivation, growth stimulation, and improvement of the beneficial features of LAB by emerging technologies.

The aim of this work was to investigate the effect of pulsed electric fields (PEF) on the growth and acidification kinetics of Lactobacillus delbrueckii subsp. bulgaricus CFL1 during fermentation. The PEF treatments were applied during the fermentation process using a recirculation pump and a PEF treatment chamber coupled with a PEF generator. The medium flow rate through the chamber was first optimized to obtain the same growth and acidification kinetics than the control fermentation without medium recirculation. Different PEF intensities (60&ndash, 428 V cm&minus, 1) were then applied to the culture medium to study the impact of PEF on the cells&rsquo, behavior. The growth and acidification kinetics were recorded during the fermentation and the specific growth rates &micro, pH, and acidification rate (dpH/dt) were assessed. The results obtained showed a biphasic growth by applying high PEF intensities (beyond 285 V cm&minus, 1) with the presence of two maximal specific growth rates and a decrease in the acidification activities. It was demonstrated that the cells were stressed during the PEF treatment, but presented an accelerated growth after stopping it, leading thereby to similar absorbance and pH at the end of the fermentation. These results show the great potential of PEF technology to be applied to generate low acidified products by performing PEF-assisted fermentations.

International audience; Fermented apple beverages are produced all over the world with diverse characteristics associated with each country. Despite the diversifications, cider producers are confronted with similar issues and risks. The nature of the raw material, also known as the fermentation medium, plays a key role in fermentation. A well-defined composition of apples is, therefore, required to produce cider with good quality. In addition, ferment and its metabolism are important factors in the fermentation process. The producers of cider and other alcoholic beverages are looking in general for novel yeast strains or for the use of native strains to produce “authentic” and diversified beverages that are distinct from each other, and that attract more and more consumers. Research articles on cider production are infrequent compared to wine production, especially on the impact of the chemical composition and microbial diversity of apples on fermentation. Even though the processing of fermented beverages is close in terms of microbial interactions and production, the study of the specific properties of apples and the production challenges of cider production is advantageous and meaningful for cider producers. This review summarizes the current knowledge on apple composition and the impact of the must composition on fermentation and yeast growth. In addition, the microbial diversity of cider, activities, and its influence on fermentation are reviewed.

The aim of this work was to investigate the effect of date seed water-soluble polysaccharides (DSP) and hemicellulose (DSH) as dietary fiber sources in enhancing the wheat bread&rsquo, s quality. DSP and DSH were extracted from the three date seed varieties Deglet Nour, Ghars Souf, and Allig. The extraction yields ranged from 3.8% to 6.14% and from 13.29% to 18.8%, for DSP and DSH, respectively. DSP and DSH showed interesting functional properties and were incorporated at 0.5% and 0.75% (w/w) in wheat flour with low bread-making quality (FLBM). The results showed that the addition of 0.75% DSH significantly improved the alveograph profile of the dough, and in a more efficient way than that of DSP. Furthermore, bread evaluation revealed that the addition of DSH considerably improved the volume (by 24.22%) and the texture profile of bread (decrease of the hardness and chewiness by 41.54% and 33.81%, respectively), compared to control bread (prepared with FLBM). A sensory analysis showed that the better overall acceptability was found for bread supplemented with DSH. Results in this work demonstrate that hemicellulose fraction extracted from date seeds (DSH) and added with a level of 0.75% to FLBM represents the component that improved bread quality the best.

The present work studied the fermentative potential and carbon metabolism of an indigenous yeast isolated from Lebanese apples for cider production. The indigenous yeast strain was isolated from a spontaneous fermented juice of the Lebanese apple variety ‘Ace spur’. The sequencing of the Internal Transcribed Spacer (ITS) domain of rRNA identified the isolated yeast strain as a member of the Hanseniaspora genus. These results suggest an intragenomic ITS sequence heterogeneity in the isolated yeast strain specifically in its ITS1 domain. The different investigations on the yeast carbon metabolism revealed that the isolated yeast is ‘Crabtree positive’ and can produce and accumulate ethanol from the first hours of fermentation. Thus, our findings highlight the possibility of using the isolated indigenous Hanseniaspora strain as a sole fermentative agent during cider production.

In this study, the physicochemical characterization, functional properties, and antioxidant activity of polysaccharides extracted from Ephedra alata (EAP) were investigated. EAP were extracted in water during 3 h with a liquid/solid ratio of 5 in a water bath at 90 &deg, C. The structure of the extracted EAP was examined by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and gas chromatography-mass spectrometry (GC-MS). The functional properties and biochemical activities of EAP were determined. The chemical analysis revealed that the contents of carbohydrates, uronic acid, and proteins were 73.24% &plusmn, 1.24%, 6.82% &plusmn, 0.57%, and 6.56% &plusmn, 0.36%, respectively. The results showed that the extracted EAP essentially contain three functional groups: C=O, C-H, and O-H. SEM images showed that EAP present numerous high porosity particles. The monosaccharide composition revealed a polymer composed of glucose (43.1%), galactose (36.4%), mannose (14.9%), arabinose (3.7%), and gluconic acid (1.7%). EAP showed interesting functional properties (solubility, oil holding capacity, foaming and emulsion properties). Finally, the results revealed that EAP displayed excellent antihypertensive and antioxidant activities. Overall, EAP present a promising natural source of food additives, antioxidants, and antihypertensive agents.

International audience; Single cell oils have been considered as potential replacers of plant and animal oils, and are mainly produced by yeasts, molds, and algae. Oleaginous yeasts have taken special attention due to the similarity of their metabolism with that of higher plants, and the numerous genetic tools available for their modification. However, a special need has been reported for efficient cell disruption technology due to the rigidity of their cell wall compared to other biological ones. This makes the conventional maceration for oil recovery usually incomplete. Several mechanical and non-mechanical cell disruption technologies have been reported in the literature and are summarized in this review. A special focus is given for bead milling, high-pressure homogenization, ultrasound-, and microwave-assisted extraction. Their advantages and limitations, as well as the future potential strategies for oil recovery from oleaginous yeasts, are discussed.

Four new amphiphilic long chain amidoamine derivatives displaying different structure variations are synthesized and tested in 27 liquids and compared to the study of two similar molecules already reported in the literature. In many cases, these compounds can act as low molecular weight gelators to form a three-dimensional network in organic liquids or water, which can be confirmed by FE-SEM observations and rheology measurements. For each sample, XRD diffraction of the corresponding xerogel and FT-IR analysis of native supramolecular gels reveal that they can self-assemble into lamellar-like aggregates or in pseudo-cubic structures, depending on the alkyl chain length and the steric hindrance of the polar head. The number of amide bonds and their positions inside gelator structures are determinant for the nature of the packing. For each gelator, we perform a series of gelation tests in each of the solvents and show that Hansen parameters, which are known characteristics of each liquid, can be used to successfully predict their gelation properties via machine learning in the vast majority of liquids at a concentration of 4 wt%.

International audience; This work aims to investigate the efficiency of bead milling combined or not with high-pressure homogenization on the cell disruption and lipid recovery from Yarrowia lipolytica oleaginous yeast. First, a simulation study involving the use of the Hansen solubility parameters’ approach was performed in order to identify, among 41 conventional and “green” solvents, the most promising ones that are able to replace n-hexane for lipid recovery from Y. lipolytica biomass. The results obtained showed that the pre-treatment involving both high-pressure homogenization and bead milling applied sequentially was more performant than that involving bead milling alone. In addition, bead-milling parameters were optimized showing an optimal bead size of 4.9 mm and a processing time of 30 s. Among the tested solvents, isoamyl acetate was selected as the most appropriate “green” solvent, maximizing the lipid extraction, compared to n-hexane. Despite the better performance of the dry route compared to the wet one, promising results were obtained towards 1) minimizing the energy consumed and 2) replacing n-hexane by “green” solvents for lipid recovery from Y. lipolytica yeast.

International audience; In this study, the optimization of ultrasound‐assisted aqueous extraction of polyphenols from pomegranate peels and seeds was conducted. A 10‐min sonication (tu ) pre‐treatment (≈60 W) accelerated the extraction kinetics and intensified the polyphenol recovery from peels and seeds. Ultrasound pre‐treatment permitted the selective recovery of polyphenols from peels by maintaining a constant concentration of the total soluble matter (°Brix) before and after sonication. Two different near‐linear correlations were found between soluble matter and polyphenol extraction for the peels’ and the seeds’ extracts. Luminescence emission spectra showed significant differences between peels and seeds extracts (tu = 10 min then diffusion for 200 min) below 450 nm and above 600 nm. Ultrasound pre‐treatment enhanced the quantity of the extracted molecules from peels and seeds without affecting their diversity. The optimal ultrasound pre‐treatment duration was 10 min, since it ameliorated the polyphenol extraction compared to 5 min, and gave the same yield as 20 min.

International audience; Edible seaweeds are a good source of antioxidants, dietary fibers, essential amino acids, vitamins, phytochemicals, polyunsaturated fatty acids, and minerals. Many studies have evaluated the gelling, thickening and therapeutic properties of seaweeds when they are used individually. This review gives an overview on the nutritional, textural, sensorial, and health-related properties of food products enriched with seaweeds and seaweed extracts. The effect of seaweed incorporation on properties of meat, fish, bakery, and other food products were highlighted in depth. Moreover, the positive effects of foods enriched with seaweeds and seaweed extracts on different lifestyle diseases such as obesity, dyslipidemia, hypertension, and diabetes were also discussed. The results of the studies demonstrated that the addition of seaweeds, in powder or extract form, can improve the nutritional and textural properties of food products. Additionally, low-fat products with less calories and less saturated fatty acids can be prepared using seaweeds. Moreover, the addition of seaweeds also affected the health properties of food products. The results of these studies demonstrated that the health value, shelf-life and overall quality of foods can be improved through the addition of either seaweeds or seaweed extracts.

Background In recent years, both food researchers and food industry have shown growing interest in Opuntia fruits, as they constitute a good source of phytochemicals such as phenolics, vitamin C, vitamin E, polysaccharides and betalains. Many of these compounds have shown antioxidant, anti-cancer, antiatherosclerotic and/or hepatoprotective properties. Moreover, the fruit is also a source of dietary fibers, which promote bowel transit, thus preventing constipation. Scope and approach Due to these properties, Opuntia fruits are considered as functional products offering numerous health benefits when are consumed as fresh or processed product. However, these compounds can lose their properties and could be transformed into antinutrients depending on processing conditions. Therefore, there is a dire need for investigating the effect of processing on bioactive compounds of Opuntia Spp. On the other hand, during Opuntia fruit processing, a large amount of waste and by-products are generated including peel, pulp and seed, which are a great source of high-added value compounds. Nowadays, extraction of valuable compounds from Opuntia by-products is drawing more and more attention, making it on the verge of commercialization. Key findings and conclusions The processing and preservation techniques strongly influence the stability of phytochemicals present in Opuntia fruits and their derived products. The available reports suggest that, along with conventional methods, novel non-thermal technologies are efficient to recover high-added value compounds from Opuntia fruit by-products/waste. Overall, high pressure processing and pulsed electric field technology have emerged as promising methods to extend Opuntia beverages shelf-life, and supercritical CO2 extraction as an effective tool to extract oils.

The aim of this work was to investigate the effects of Ohmic heating-assisted hydrodistillation (OAHD), applied at different voltages (100, 150, and 200) V, on the qualitative and quantitative characteristics of extracted essential oil from oregano herb ( Origanum vulgare subsp. viride ), compared to a conventional hydrodistillation (HD) procedure. The compositions of the extracted essential oils (using OAHD and HD) were assessed using gas chromatography - mass spectrometry (GC–MS). A 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH) method was applied in order to evaluate antioxidant activity. The antimicrobial activity as well as the minimum inhibitory concentration (MIC) values of the samples against Bacillus cereus, Escherichia coli O157:H7, Salmonella Typhimurium, Pseudomonas aeruginosa , and Staphylococcus aureus were determined. Among 50 identified compounds; thymol and 4-terpineol were the most abundant components independently of the technique used (OAHD or HD). No significant differences were observed between HD and OAHD (all voltages) methods in terms of extraction yields, and between HD and OAHD (at 100 V) in terms of antioxidant activity (the half inhibition concentration values (IC 50 ) were 33.4 μg/mL and 31.2 μg/mL, respectively). However, the extraction time was significantly reduced when OAHD extraction was used compared to HD. For the antimicrobial activity, the MIC values indicated higher inhibitory activities against S. aureus and B. cereus (with similar MIC values of 6.25 μg/mL) than P. aeruginosa (25 μg/mL). However, no significant influence was observed between the different applied voltages and the two extraction methods. OAHD could thus be used as “green” extraction method compared to HD. Industrial relevance The production of essential oils at industrial scale is mainly performed using conventional hydrodistillation method. However, the increasing need in applying more efficient and sustainable extraction processes has led researchers to evaluate new alternative non-conventional methods in order to replace the existing ones. Among non-conventional technologies applied to extract essential oils from plant materials, Ohmic-assisted hydrodistillation is of great potential. It allows reducing the extraction time compared to conventional hydrodistillation, which reduces significantly the energy consumption. The implementation of Ohmic-assisted hydrodistillation technology in essential oil producing industries is therefore of great importance.

International audience; Context: Nitraria retusa (Forssk.) Asch. (Nitrariaceae) is a medicinal plant which produces edible fruits whose antioxidant activity has been demonstrated.Objective: The current study elucidates the potential protective effect of N. retusa fruit aqueous extract against nephrotoxicity induced by penconazole, a triazole fungicide, in the kidney of adult rats.Materials and methods: Adult Wistar rats were exposed either to penconazole (67 mg/kg body weight), or to N. retusa extract (300 mg/kg body weight) or to their combination. Penconazole was administered by intra-peritoneal injection every 2 days from day 7 until day 15, the sacrifice day, while N. retusa extract was administered daily by gavage during 15 days. Oxidative stress parameters, kidney biomarkers and histopathological examination were determined.Results: Nitraria retusa extract administration to penconazole treated rats decreased kidney levels of malondialdehyde (-10%), hydrogen peroxide (-12%), protein carbonyls (PCOs, -11%) and advanced oxidation protein products (AOPP, -16%); antioxidant enzyme activities: catalase (-13%), superoxide dismutase (-8%) and glutathione peroxidase (GPx, -14%), and the levels of non-enzymatic antioxidants: non-protein thiols (-9%), glutathione (-7%) and metallothionein (-12%). Furthermore, this plant extract prevented kidney biomarker changes by reducing plasma levels of creatinine, urea, uric acid and LDH and increasing those of ALP and GGT. Histopathological alterations induced by penconazole (glomeruli fragmentation, Bowman's space enlargement, tubular epithelial cells necrosis and infiltration of inflammatory leucocytes) were attenuated following N. retusa administration.Discussion and conclusion: Our results indicated that N. retusa fruit extract had protective effects against penconazole-induced kidney injury, which could be attributed to its phenolic compounds.

International audience; Electrospinning is considered a promising technology for fabricating ultrafine fibers via the application of electrostatic repulsive forces. Electrospun nanofibers produced via emulsion electrospinning are widely used as delivery systems to encapsulate bioactive compounds and drugs in food and pharmaceuticals, respectively. Emulsion electrospinning has also gained significant interest for the production of vehicles for sustained and controlled release. There are several parameters affecting the properties of fabricated fibers including the type of emulsion, emulsion composition, electric field strength, conductivity of solution, surface tension, electrode configuration, solution cooling time, dissolution temperature, and solution flow rate; therefore, all these parameters should be precisely controlled to obtain optimum results. Some of the advantages of these fibers are the protection of encapsulated materials from environmental conditions, room temperature processes, release rate control and high loading efficiency. This study presents an overview of the emulsion electrospinning method, its mechanism of action and its applications in both the food and pharmaceutical fields.

The present work explored a catalytic transfer hydrogenation process with several supported noble metal on carbon as catalysts for the production of γ-valerolactone (GVL) from methyl levulinates (ML) in iso-propanol (2-PrOH) and the performance of the commercial 5%Ru/C in continuous flow were investigated, GVL yields up to 83% at 150 °C (40 bar) using a high load (0.4 M ML) feed at 0.8 mL/min flow rate. The catalyst productivity (Pr) equal to 0.99 mol g−1 h−1. Methyl 4-hydroxypentanoate (MHP) were produced as major side product in lower amounts in continuous flow mode. Long-term (9 h) catalyst stability experiment showed good stability under optimum condition. The yield of GVL obtained from ethyl levulinate, butanol levuliante and levulinate acid were ca.21%, 54% and 26% less than ML in 2-PrOH and Pr were 0.43, 0.73 and 0.48 less respectively. There is no obvious hydrogenation process when changed 2-PrOH to ethanol and 1-butanol.

International audience; The present work studies the impact of low-intensity ultrasound (US) on Hanseniaspora sp. yeast fermentations. The effect of pulse duration and growth phase on US application was first evaluated using a synthetic medium. The optimal conditions were then applied to apple juice US-assisted fermentation. An US treatment chamber was first designed to allow the recycling of the culture medium. The optimal US pulse duration on the yeast growth rate was of 0.5 s followed by 6 s rest period, and during 6 h of both Lag and Log phases. These US parameters led to a faster consumption of glucose in the medium during the fermentation, compared to the untreated culture. The impact of US was also depending on the growth phase, showing higher sensitivity of the yeast to US during the Lag phase rather than the Log phase. US-assisted fermentation of apple juice showed a significant increase in biomass growth and glucose consumption, along with a significant decrease in the ethanol yield. The fastest growth kinetic (by 52%), and the highest ethanol reduction (by 0.55% (v, v)) were obtained for the treatment during the first 12 h of fermentation, thereby, the stationary phase was reached faster, and the maximum biomass growth rate was 10 folds higher compared to the untreated culture. The results obtained in this study demonstrated the promising efficiency of US-assisted fermentation in stimulating the biomass growth and reducing the ethanol content in alcoholic beverages.

With the emergence of multi-drug resistant bacteria and hospital-acquired infections, there is an urgent need to develop new antibiotics. Here, we report the synthesis, physico-chemical characterizations, and antimicrobial activity assays of four Azo compounds that differ in their alkyl chain length. The molecular mechanism of their antibacterial activity was investigated by complementary in vitro and in silico biophysical studies. The compounds with alkyl chain lengths of four or six carbons showed a low MIC50 against Escherichia coli and Bacillus subtilis. Our investigations into the mechanism of their action revealed that phosphatidylethanolamine in the bacterial plasma membrane plays an important role in their antibacterial activity.

Microwave-assisted extraction (MAE) at atmospheric pressure has been demonstrated as an efficient technology for the extraction of polymeric hemicelluloses from spruce sawdust. This technology was shown to be more efficient than conventional extraction. MAE leads to a high solubilization of wood and a selective extraction of hemicellulose polymers with high molecular weights. To optimize MAE, different treatment powers (125–573 W) of presoaked spruce sawdust in water and 1 M sodium hydroxide solution for a period of 60 min were tested. The yield of hemicellulose extraction increased with the microwave power in both mediums, but with a clear advantage for presoaked samples in basic medium. The characterization of extracted hemicelluloses has shown high extraction selectivity depending on the medium of impregnation of sawdust before MAE: High-molecular-mass acetylated galactoglucomannans (Mw ∼ 41 kDa) were isolated after presoaking in water and higher molecular mass arabinoglucoronoxylans (Mw ∼ 66 kDa) in basic medium.

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Deep eutectic solvents (DESs), especially those made of choline chloride and urea mixtures are a different type of ionic liquids recognized for their ability to solubilize metal chlorides. In this work, a well-known long alkyl aminoamide gelator was added to a metal salt solution in DES to obtain a more viscous solution or a more robust gel when introduced at the higher concentrations. These supramolecular gels could be employed as template for the generation of small noble metal nanoparticles of narrow distribution such as AuNPs or CoNPs without need of seed or reducing agent addition, immobilized in the gel matrix and also homogeneous in shape and size. All gel samples were studied by FE-SEM observation, XRD, FT-IR spectroscopy, rheology measurement and DSC. When formed, the isolated nanoparticles were evaluated by UV–vis spectroscopy and TEM observation. Once formed, their average diameters were 15 nm.

Nine new dithiocarbamic esters derived from bio-based acrylic acid were synthesized and evaluated for their in vitro antifungal activity against the phytopathogenic fungus Fusarium solani and fungi-like oomycete Phytophthora infestans. Among these nine dithiocarbamic derivatives, compound 6 (tert-butyl 3-(N,N-diethyldithiocarbamoyl)-propanoate) showed interesting antifungal efficacy at low concentration compared to the other tested dithiocarbamates. The structure–antifungal activity relationship of these designed dithiocarbamic esters is discussed.

International audience

International audience; Thermal treatment is one of the main unit operations applied to improve the microbiological quality of food products. It utilizes the lethal effects of heat against thermosensitive microorganisms, both pathogens and spoilage organisms; however, at the same time it induces degradation of the organoleptic and nutritional properties of foods due to non-enzymatic Maillard reactions. These reactions occur between amino compounds and reducing sugars, and are intensified with the increase of temperature. Some research studies have investigated the potential use of emerging technologies such as pulsed electric fields, ohmic heating and high hydrostatic pressure to reduce the occurrence of non-enzymatic browning in foods during processing. Despite of the numerous advantages of emerging technologies over conventional ones, their impact on Maillard reactions is complex and not well understood with both positive and negative impacts. This chapter reviews the impact of emerging technologies on Maillard reactions in foods.

International audience; This text comprehensively covers novel, innovative technologies used in the food and beverage industries in order to provide safe and healthy foods for consumers. The research provided in these chapters aims to show that the traditional pasteurization and commercial sterilization of foods result in unacceptable quality and nutrient retention, creating an important need for alternative methods used to minimize undesirable reactions such as thermal decomposition or degradation. Emerging processing methods to minimize heat induced alterations in foods and their applications are covered in-depth, demonstrating that these methods are useful not only for the inactivation of microorganisms and enzymes but also for improving the yield and development of ingredients and marketable foods with higher quality and better nutritional characteristics. Effect of Emerging Processing Methods on the Food Quality: Advantages and Challenges not only covers the advantages of using innovative processing methods, but also the disadvantages and challenges of using these techniques on food quality. Each chapter focuses on a different emerging processing technique, breaking down the sensory, textural and nutritional aspects for different food products in addition to the advantages and challenges for each method. New technologies and advanced theories are a major focus, pointing to innovative new paths for the quality and safety assurance in food products. From pulsed electric fields to ultrasounds, this work covers all aspects of emerging processing techniques for fruits and vegetables, foods and dairy products.

The synthesis of semiconductor metal/metal oxide nanoparticles (NP) via the green synthesis routes is desirable due to its effectiveness, economical, and eco-friendly nature of the products. The present study aims to synthesize the titanium dioxide (TiO2) NP via the green synthesis route, using Myristica fragrans plant extract as the reducing agent, where the photocatalytic activity was evaluated. The physicochemical and morphological properties of TiO2 NP have been analyzed using spectroscopic and electron microscopic techniques. From the analysis, the powdered X-ray diffraction (XRD) indicated the formation of very well crystalline TiO2 particles in the anatase phase, while the Fourier transform infrared (FTIR) spectroscopy confirmed the presence of Ti O bonds, and UV–Vis spectroscopy proofed the optical properties. The field emission scanning electron microscopy (FESEM) analysis provided the surface morphological characteristics and the formation of spherical shape particles; and the electron diffraction X-ray analysis (EDX) indicated the elemental composition. The photocatalytic activity of the TiO2 NP was evaluated based on the degradation rate of two aqueous dye solutions, i.e. methylene blue (MB) and congo red (Con-R) using the 8 W Xenon lamp as the light source for the visible irradiation. The degradation activity of the Con-R dye is slightly higher (99% degradation in 45 min) than that of the MB dye (97% degradation in 60 min). Both degradations activity followed the first-order kinetic model. The high activity of TiO2 NP on both dyes was supported by the increased absorption of light, associated charge separation efficiency, and specific surface area as provided by the UV–Vis DRS analysis. The plant extract mediated the synthesis of TiO2 which formed stable particles without losing the semiconducting and photocatalytic properties, where the holes (h+) and superoxide radicals ( O2−) contributed to the enhanced degradation of dye. The antibacterial activity of the TiO2 NP (50 and 100 µg/mL; 6 h) synthesized was evaluated by testing against two different bacterial cultures of K. pneumoniae and S. aureus. The results proved that the particles became active only in the presence of UV light exposed and no significant differences in bacterial inhibition efficiency between the two cell types (79% and 72%) as observed. The antibacterial activity of the TiO2 NP was proven by the epifluorescence microscopic analysis, total viable count (TVC), and zone of inhibition (ZOI).

New materials that mimic natural bone properties, matching functional, mechanical, and biological properties have been continuously developed to rehabilitate bone defects. Desirably, ‘tissue engineering’ has been a multidisciplinary ground that uses the principles of life sciences and engineering for the biological replacements that restore or replace the tissue function or a whole organ. Nevertheless, the bone grafting treatment has numerous restrictions, counting the major hazards of morbidity from the sites where donor bone grafts are removed, the likelihood for an immune rejection or bacterial transport from the donor site (in case of allogeneic grafting), and the inadequate availability of donor bone grafts that can meet the current demands. Since the proper growth of synthetic materials for implantable bones encourages the reconstruction of bone tissues by providing strong structural support without any damages to the interferences of biological tissue. To serve for such behavior, the biodegradable matrices provide temporary scaffolds within which the bone tissues can be regenerated. Typically, the thermoplastic aliphatic polyesters are found to serve this purpose. The great significance of this field lies in the in vitro growth of precise cells on porous matrices (scaffolds) to generate three-dimensional (3D) tissues that can be entrenched into the location of tissue/bone damage. Numerous gifts have been gifted by our nature to advance and preserve the well-being of all living things either directly or indirectly. This review focuses on the recent advances in polymer-based hydroxyapatite scaffolds including their properties and applications.

International audience; The aim of this work was to investigate the effect of almond gum as dietary fibre source in enhancing the wheat bread quality. Different amounts of almond gum (2%, 5% and 10% (w/w)) were used in bread formulation. The volume, texture, crust and crumb colour, as well as the sensorial properties, were evaluated and compared to control (without almond gum). The obtained results showed that almond gum addition enhanced significantly the volume of bread. The highest volume was obtained using 2% almond gum concentration with 23.6% increase, compared to control. Using almond gum in bread formulation improved considerably its texture with a notable decrease in hardness by 61.7% and 42.5% when using 2% and 5% almond gum, respectively. The sensory analysis scores showed that the better overall acceptability was found for breads supplemented with 2% almond gum, as compared to control and breads supplemented with 5% or 10% almond gum.

Background Negative pressure cavitation (NPC) extraction is a novel effective and eco-friendly technology. In this method, cavitation is generated by negative pressure and continuously introduced into the liquid-solid system to enhance the turbulence, collision and mass transfer between the extracting solvent and solid matrix. This technique was found to be efficient for improving the substrate and enzyme mixing, increasing the enzymatic hydrolysis of the plant cell wall components and improving the intracellular contents release into the extraction solvent. Scope and approach So far, several studies evaluated the feasibility of using this system alone or in combination with other extraction methods (e.g. enzyme, homogenization, microwave, ionic liquid solvents and deep eutectic solvents) for extraction of food active compounds (e.g. flavonoids, isoflavonoids, saponins, stilbenes, polyphenols and alkaloids) from plant materials. This review gives an overview of the principle of NPC method and its application alone or in combination with other extraction techniques for extraction of active compounds from plant materials. Key findings and conclusions The outcome of the studies using NPC demonstrated that this technique is a simpler procedure, requiring low cost, and provides high efficiency. It is eco-friendly, and possesses a remarkable potential application in the industrial production compared to other extraction techniques. Moreover, since this method is performed at room temperature, it can reduce or prevent the degradation of thermosensitive compounds.

International audience; In recent years, great interest has been devoted to the development of new applications for natural gums. These molecules were used for a variety of purposes since they are chemically inert, non-toxic, less expensive, biodegradable and widely available. They represent one of the most abundant raw materials used not only in commercial food products, but also in cosmetic and pharmaceutical products. Plant gums take their advantages compared to other gums (e.g., from animal and microbial sources) mainly because of their acceptance by consumers. Despite of the well description given in literature for the features of plant gum exudates, there is a lack distinguishing the different families that are producing gums, and their potential applications. Among these gums, the ones produced by Rosaceae family (e.g., almond, apricot, cherry, peach, and plum plants) have been taking special attention. Thus, the aim of this review is to report the recent advances in Rosaceae gum exudates. An emphasis is given for the formation mechanisms of these gums, their chemical composition, functional properties and structures, beneficial properties, as well as their food/non-food applications.

Background Wine production represents one of the major agricultural activities worldwide. This production is accompanied with the generation of tremendous amounts of wastes and by-products exceptionally rich in bioactive compounds (especially phenolics). Recovering these molecules constitutes a key point for the valorization of the wine-processed materials, making them on the verge of commercialization. Regarding the health related benefits of these molecules; they could be used as additives for food and cosmetic products. Scope and approach The current review is revising the potential of alternative extraction methodologies for the recovery of antioxidant bioactive compounds from winery wastes and by-products. Conventional (solid liquid extraction, heating, grinding, etc) and non-conventional (pulsed electric fields, high voltage electrical discharges, pulsed ohmic heating, ultrasounds, microwave-assisted extractions, sub- and supercritical fluid extractions, as well as pressurized liquid extraction) methods have been applied for the extraction of high-added value compounds from winery-processed materials. Key findings and conclusions Non-conventional technologies represent a promising tool to recover high-added value compounds from winery wastes and by-products. However, several parameters are influencing the choice of technology used to recover these compounds, such as the matrix being processed, the selectivity, the energy consumption, the equipment cost, and the value of the extract.

International audience; The aim of this work was to investigate the impact of almond gum as coating agent to decrease the oil absorption and to increase the moisture content of fried potato chips meaning a Box–Behnken design. The studied parameters were: almond gum concentration (0–20 g/L), frying time (30–120 s) and frying temperature (160–190 °C). Results showed that the increase of almond gum concentration up to 20 g/L decreased the oil uptake of potato chips by 34% and increased the moisture by 29.5%. Optimal coating and frying conditions found with RSM were thus achieved with 20 g/L aqueous almond gum, 75 s frying time at 160 °C frying temperature. Additionally, the study of sensorial analysis (color, appearance, crispiness, taste, odor, appetence) showed that the chips coated with almond gum have an overall acceptability better than the uncoated potato chips, and the ones coated with arabic gum. The textural analysis of potato chips showed that the hardness (rigidity) decreased significantly by coating either with almond gum or arabic gum. The results obtained through this work showed that coating with almond gum improves the sensorial and nutritional qualities of potato chips.

International audience; C-H activation with transition metal catalysis has become an important tool in organic synthesis for the functionalization of low reactive bonds and the preparation of complex molecules. The choice of the directing group (DG) proves to be crucial for the selectivity in this type of reaction, and several different functional groups have been used efficiently. This review describes recent advances in C-H functionalization of aromatic rings directed by a N-tosylcarboxamide group. Results regarding alkenylation, alkoxylation, halogenation, and arylation of C-H in the ortho position to the tosylcarboxamide are presented. Moreover, the advantage of this particular directing group is that it can undergo further transformation and act as CO or CON fragment reservoir to produce, in sequential fashion or one-pot sequence, various interesting (hetero)cycles such as phenanthridinones, dihydroisoquinolinones, fluorenones, or isoindolinones.

International audience; Two-step procedure with the initial aqueous extraction from raw microalgae Nannochloropsis oculata and secondary organic solvent extraction from vacuum dried (VD) microalgae were applied for selective recovery of bio-molecules. The effects of preliminary aqueous washing and high voltage electrical discharges (HVED, 40 kV/cm, 4 ms pulses) were tested. The positive effects of HVED treatment and washing on selectivity of aqueous extraction of ionics and other water-soluble compounds (carbohydrates, proteins and pigments) were observed. Moreover, the HVED treatment allowed improving the kinetic of vacuum drying, and significant effects of HVED treatment on organic solvent extraction of chlorophylls, carotenoids and lipids were determined. The proposed two-step procedure combining the preliminary washing, HVED treatment and aqueous/organic solvents extraction steps are useful for selective extraction of different bio-molecules from microalgae biomass.

In the present research work, the physicochemical and fermentative properties of the “Ace spur” apple variety, obtained from a Lebanese farm, and the “Kermerrien” variety, obtained from a French cider industry, were investigated. The pomological properties were first determined for both varieties showing significant differences in the shapes and sizes. Sugar content, titratable acidity, soluble solids, and pH values were then determined. The potential of the “Ace spur” apple juice was then evaluated using the yeast strain Hanseniaspora sp., a major yeast found during the spontaneous fermentation of apples. “Ace spur” apples contained more sugars while the “Kermerrien” cultivar had a highest malic acid and polyphenol concentrations. After 100 h of fermentation, the ethanol percentage (v/v) was around 4% in both ciders. Results obtained in this work revealed the chemical potential of the Lebanese apple juice to produce cider.

This article focuses on the state-of-the-art advancements on the production of isosorbide, a furanic diol exclusively produced via a two-steps dehydrocyclisation of sorbitol; polyol acquired from the catalytic reduction of glucose. Generally, the compound is formed admixed with various types of monocyclic ethers called sorbitans. During the past half century, many researchers tried to explore the underlying mechanistic and kinetic aspects of the reactions involved in its formation with the main objective to increase the selectivity thus avoiding the formation of 2,5-sorbitan by-product. In the intervening years, new energy-saving and environmental-friendly methods have been developed, especially those that involve heterogeneous catalysts or acidic ionic liquids. In order to improve the catalytic activities of catalysts, it is imperative to measure the impact of their intrinsic acidity strength, porosity and surface hydrophobicity on each stage of the formation of bicyclic furanic compound. Additionally, comparative advantageous features of simple protocols involving acidic deep eutectic solvent employed as catalyst in solvent-free microwave-assisted reaction, are highlighted.

International audience; Reverse engineering is when a real part is analysed in detail in order to create a numerical or virtual model. Reverse engineering allows for multiple redesign possibilities, including changes in the material, the shape and the parameters of the part. Reverse engineering is mostly a manual activity for companies and is thus time consuming. Indeed, measurements must be done in scanned files in order to fit sketches on a mesh and to finally rebuild the computer-aided design/bill of material. This manual process is acceptable when reverse engineering is exceptional. But it is considered as a non-value task when reverse engineering is routine. This non-value task could be automated, at least partially. To make it possible, a capitalization of the company’s part catalogue is a necessary step to proceed. The use of this capitalization can then drive the reverse engineering tasks to enable faster redesign possibilities. The aim of this contribution is thus to propose a knowledge model to support reverse engineering activities in order to integrate the reversed parts quickly into the new product’s detailed design. An extended knowledge framework based on the core product model is proposed, and a use case is shown to validate the feasibility of the proposal of the reverse engineering methodology called PHENIX

International audience; Various food‐grade emulsion‐based delivery systems have been developed for the encapsulation of functional food ingredients. This is because many food components (e.g. minerals, oil‐ and water‐soluble pigments, vitamins, phenolic compounds, proteins and amino acids, oils, and micro‐organisms) are sensitive to extreme conditions such as pH, ionic strength, light, temperature, oxygen, and gastrointestinal conditions. Moreover, undesired reactions could occur when these functional components are incorporated in certain food matrices. Multiple emulsions have great potential to be used as edible delivery systems to encapsulate, protect, and control release, target delivery, and inhibit unfavorable chemical reactions of different food ingredients. This chapter provides an overview of work done on multiple emulsions for food applications covering different aspects, including their fabrication, composition, characterization, and digestion as well as their application as carriers for the delivery of food active compounds.