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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

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.

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.

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; 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.

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.

Background A large amount of wastes and by-products are generated during olive oil production process. Traditionally, these products have been considered as a problem. However, they constitute a great source of high-added value compounds, which have the potential to be used as food additives and/or nutraceuticals. Therefore, valorization of wastes and by-products from food industry kills two birds with one stone and addresses both the use of waste and by-products and societal health, thus greatly contributing for a sustainable food chain from an environmental and economical point of view. Scope and approach In the present review, current and new insights in the recovery of high-added value compounds from wastes and by-products generated during olive oil production process will be discussed. Several conventional (solvent, heat, grinding) and non-conventional methodologies (ultrasounds, microwaves, sub- and supercritical fluid extractions, pressurized liquid extraction, pulsed electric fields and high voltage electrical discharges) have been investigated for the recovery of high-added value compounds (polyphenols, fatty acids, coloring pigments (chlorophylls and carotenoids), tocopherols, phytosterols, squalene, volatile and aromatic compounds) from wastes and by-products generated during olive oil production process. Key findings and conclusions Non-conventional technologies can constitute a promising tool to recover high-added value compounds from olive oil wastes and by-products. However, the content of these valuable compounds can vary greatly depending on the matrix and the efficiency in the recovery of these compounds is highly dependent of the technology used for extraction.

International audience; The aim of this work was to evaluate the efficiency of different cell disruption techniques on oil extraction from Y. lipolytica oleaginous yeast. The techniques tested were mechanical expression (ME), moderate pulsed electric field assisted mechanical expression (MPEF-ME), high pulsed electric fields (HPEF), high voltage electrical discharges (HVED), ultrasound (US), and high-pressure homogenization (HPH). The impact of each cell disruption technique on fatty acid composition was investigated. Results show that the most efficient technique for Y. lipolytica disruption was HPH leading to the obtaining of 83.8 ± 4.8% oil extraction yield, compared to only 19.8 ± 0.5% for the control, without any pre-treatment. In terms of fatty acid composition, HVED induced significant changes in almost all the analyzed fatty acids, while US was the softest technique. HPH, ME, and MPEF-ME induced changes in the content of some fatty acids.