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Background: This study investigated the amino acids, phenolic compounds and volatile compounds in Maazoun melon seeds. The functional properties of melon seed flour, such as bulk density, swelling capacity, emulsifying capacity, and foaming capacity were also determined.; Results: The findings proved that the functional properties of melon seeds make them useful for incorporation into different food formulations to improve their functionality. The determination of the amino acid composition of melon seeds showed that glutamic acid (205.23 g kg-1 ), arginine (130.44 g kg-1 ), and tryptophan (129.91 g kg-1 ) were the major amino acids of the protein fraction. Chromatographic analysis indicated that phenolic acids (47.78%) constituted the main phenolic class, followed by flavonoids (27.15%). Naringenin-7-O-glycoside and gallic acid were the most abundant phenolic compounds. Gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) analyses of the volatile compounds demonstrated that esters and terpenoids were the main volatile groups. The study of histological structures showed that melon seeds consist of three distinguishable parts: tegument, endosperm cells, and almond.; Conclusion: The results obtained revealed that melon (Cucumis melo L.) seeds may be a potential source of bioactive compounds and natural substances with nutritive value and functional properties of interest to industrial applications. © 2018 Society of Chemical Industry.; © 2018 Society of Chemical Industry.

In this work, the effect of Detente Instantanee Controlee (DIC) (French for instant controlled pressure drop) on the total polyphenol, flavonoids, α-tocopherol contents, and antioxidant activities of olive leaves was studied. Olive leaf extracts were pre-treated at one cycle DIC under 0.1 MPa pressure for 11 s and followed by an extraction with 95% ethanol at 55 °C during 3 h. The phenolic compounds, flavonoids, oleuropein, and α-tocopherol contents were determined, showing 66.63 mg gallic acid equivalent (GAE)/g db, 12 mg catechin equivalent (CE)/g db, 43.9 mg/g db, and 0.15 mg/g db for the untreated leaves against 239.37 mg GAE/g db, 28 mg CE/g db, 70.3 mg/g db, and 0.59 mg/g db for DIC-treated leaves, respectively. Therefore, DIC allows more availability of bioactive compounds contributing to a high antiradical activity (DPPH) compared to a synthetic antioxidant butylated hydroxytoluene (BHT). Both extracts showed a total antioxidant capacity (method of phosphomolybdenum) greater than that of the standard BHT. Likewise, both extracts have a reducing power (FRAP test) significant concentration-dependent. The DIC-treated leaves showed a higher antioxidant capacity compared to that of untreated leaves. Thus, DIC could be an effective treatment to promote the extraction of bioactive molecules of high antioxidant activities from olive leaves.

The present study is conducted to investigate the effect(s) of ultrasonic pretreatment on the extraction of essential oils from dried leaves of lemongrass (Cymbopogon flexuosus) by hydro-distillation. The drying process was carried out within a forced convective dryer at 50 °C and a drying air velocity of 1 m/s. Using a response surface methodology (RSM) based on central composite design with the face centered, the obtained optimum conditions were as follows: an ultrasound pretreatment for 25 min within a power of 250 W, at 50 °C. Modeling showed that all factors (time, power and temperature) were found to be highly significant in the extraction process (p

Studies were conducted on the chemical composition of melon (Cucumis melo L.) seeds, Maazoun variety. Melon seeds were found to contain (on a dry weight basis): moisture (7.16%), oil (30.65%), protein (27.41%), ash (4.83%), carbohydrate (29.96%), fibers (25.32%) and considerable amounts of antioxidant substances as phenolic compounds. The major mineral elements were: potassium, magnesium and calcium. The chemical composition of oil extracted from melon seeds was investigated. The main fatty acids of melon seed oil were linoleic acid and oleic acid. The chromatographic analysis of phenolic compounds showed that flavonoids were the most important group with predominance of amentoflavone (32.80 μg/g). Besides, melon seed oil presented considerable amounts of phytosterols in which β-sitosterol was the major sterol accounting for 206.42 mg/100 g. The seed oil was also found to be rich in tocopherols with a predominance of β+γ-tocopherol fraction. The obtained results revealed that melon seeds presented an alternative source of plant oil which may serve as raw material for food applications.

This study aimed to evaluate the characteristic features, phenolic compounds and thermal analysis of melon seed oil (Maazoun variety), in order to determine its potential applications in food or pharmaceutical industries. The physicochemical properties of the seed oil revealed a high degree of unsaturation. The average contents of carotenoid and chlorophyll were 2.43 mg/kg and 5.70 mg/kg, respectively. The main fatty acids of melon seed oil were linoleic acid (68.98%) and oleic acid (15.84%), which makes this oil nutritionally valuable. Furthermore, trilinolein (LLL), accounted for 28.99% and constitutes the most abundant triacylglycerol. A chromatographic analysis showed that amentoflavone and luteolin-7-glycoside were the major phenolic compounds. A thermal analysis of melon seed oil was performed by differential scanning calorimetery (DSC). The results of sensorial properties indicated that melon seed oil is appreciated by tasters. The findings suggested that because of its composition, melon seed oil could be used successfully as an alternative source in the food and nutraceutical industries as a functional ingredient. El objetivo de este estudio fue la caracterización, evaluación de compuestos fenólicos y el análisis térmico del aceite de semillas de melón (variedad Maazoun), con el fin de conocer sus potenciales aplicaciones en la industria alimentaria o farmacéutica. Las propiedades fisicoquímicas del aceite de semilla mostraron un alto grado de insaturación. El contenido promedio de carotenoides y clorofila fue de 2,43 mg/kg y 5,70 mg/kg, respectivamente. Los principales ácidos grasos del aceite de semilla de melón fueron el linoleico (68,98%) y oleico (15,84%), lo que hace que este aceite sea nutricionalmente valioso. Además, la trilinoleína (LLL) que representó el 28,99% constituye el triacilglicerol más abundante. El análisis cromatográfico mostró que amentoflavona y luteolin-7-glucósido eran los principales compuestos fenólicos. El análisis térmico del aceite de semilla de melón se realizó mediante calorimetría diferencial de barrido (DSC). Los resultados de las propiedades sensoriales indicaron que los catadores aprecian el aceite de semilla de melón. Los hallazgos sugieren que, debido a su composición, el aceite de semilla de melón podría utilizarse con éxito como una fuente alternativa en la industria alimentaria y nutracéutica como ingrediente funcional.

Background Proteases are hydrolytic enzymes that catalyze peptide linkage cleavage reactions at the level of proteins and peptides with different degrees of specificity. This group draws the attention of industry. More than one protease in three is a serine protease. Classically, they are active at neutral to alkaline pH. The serine proteases are researched for industrial uses, especially detergents. They are the most commercially available enzyme group in the world market. Overall, fungi produced extracellular proteases, easily separated from mycelium by filtration. Results A new basidiomycete fungus CTM10057, a hyperproducer of a novel protease (10,500 U/mL), was identified as Pleurotus sajor-caju (oyster mushroom). The enzyme, called SPPS, was purified to homogeneity by heat-treatment (80 °C for 20 min) followed by ammonium sulfate precipitation (35–55%)-dialysis, then UNO Q-6 FPLC ion-exchange chromatography and finally HPLC-ZORBAX PSM 300 HPSEC gel filtration chromatography, and submitted to biochemical characterization assays. The molecular mass was estimated to be 65 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), Native-PAGE, casein-zymography, and size exclusion by HPLC. A high homology with mushroom proteases was displayed by the first 26 amino-acid residues of the NH2-terminal aminoacid sequence. Phenylmethanesulfonyl fluoride (PMSF) and diiodopropyl fluorophosphates (DFP) strongly inhibit SPPS, revealing that it is a member of the serine-proteases family. The pH and temperature optima were 9.5 and 70 °C, respectively. Interestingly, SPPS possesses the most elevated hydrolysis level and catalytic efficiency in comparison with SPTC, Flavourzyme® 500 L, and Thermolysin type X proteases. More remarkably, a high tolerance towards organic solvent tolerance was exhibited by SPPS, together with considerable detergent stability compared to the commercial proteases Thermolysin type X and Flavourzyme® 500 L, respectively. Conclusions This proves the excellent proprieties characterizing SPPS, making it a potential candidate for industrial applications especially detergent formulations.

The hyperlipidemia is a serious health problem that increases the risk of many complications including cardiovascular disease. This study aims to evaluate the possible antihyperlipidemic effects of the feather protein hydrolysate (FPH) in a mice fed with a high‐fat diet (HFD)‐fed mice during 5 weeks. The FPH administration improved dose‐dependent lipid profile, as well as the liver and renal dysfunction indices in hyperlipidemic mice. The FPH also restored the antioxidant status in liver, kidney, and heart by lowering the lipid peroxidation and enhancing the antioxidant enzymes (catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase [SOD]). Moreover, the histological studies proved that FPH administration prevents hepatic steatosis, glomerular hyperfiltration risk, and cardiac muscle hypertrophy. Accordingly, the FPH is a promising novel medicinal ingredient for possible use in the hyperlipidemic treatment and related complications.

Biological silages were prepared from shrimp head and octopus viscera by-products recuperated from the Tunisian seafood industry. Physical and biochemical changes and microbiological profiles were determined for raw materials during fermentation and on end products. Results showed that biological silage significantly affected (P

The aim of this investigation is to study the impact of the technology of instant controlled pressure drop: “DIC” on the kinetics extraction of olive leaf ( Olea europaea L.) polyphenols. The conditions of extraction were: ethanol 95%, temperature: 55 °C and ratio r = 40 g g −1 dry basis for 3 h. The extraction kinetics of total polyphenols content (TPC) of DIC-treated and untreated leaves were performed according to the method of Folin–Ciocalteau. The ultra-performance liquid chromatography (UPLC) was used to study the extraction kinetics of seven phenolic compounds of olive leaves: apigenin-7-glucoside, hydroxytyrosol, luteolin-7-glucoside, oleuropein, tyrosol, vanillic acid, and verbascoside. DIC-assisted solvent extraction allowed reducing the extraction time from 120 to 15 min while increasing the extracted yields. Phenomenological analysis of extraction kinetics was determined through the two-stage Coupled Washing/Diffusion CWD kinetic model. DIC texturing could, in favorable cases, increase the starting accessibility and systematically the internal effective diffusivity for phenolic compounds.

To explore the efficiency of xylitol chewing gum enriched or not with remineralizing agents to protect tooth against cariogenic biofilm formation and demineralization. Six groups of chewing gums were prepared; Group 1: isomalt (1.8%), Group 2: casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) (3%) + isomalt (1.8%), Group 3: hydroxyapatite (HAP) (2.5%) + isomalt (1.8%), Group 4: xylitol (1.8%), Group 5: CPP-ACP (3%) + xylitol (1.8%) and Group 6: HAP (2.5%) + xylitol (1.8%). The antibiofilm properties of different chewing gum extracts using seven oral bacterial species including Streptococcus mutans, Streptococcus constellatus, Streptococcus Salivarius and Streptococcus oralis were explored via the crystal violet staining assay. The remineralizing effects of those products were assessed on thirty human permanent teeth, half-protected with varnish before chemical erosion and thermocycling process with chewing gum. Remineralization was evaluated using scanning electron microscopy and microscopic measurements on polarized light microscopy. The ratio R comparing the thickness between unvarnished and varnished sides was evaluated. While the minimum biofilm inhibitory concentration (MBIC50) was low for xylitol alone compared to isomalt, it was inconsistent when enriched with remineralizing agents. The minimum biofilm eradication concentration (MBEC50) was low for xylitol groups compared to isomalt, for all the studied strains. R was significantly lower in Group 1 and Group 2, while Group 6 showed the highest ratio. Xylitol chewing gums confirmed good antibiofilm properties and showed remineralized potential on eroded teeth. When xylitol is associated to CPP-ACP or HAP, antibiofilm activity decreased while remineralization of eroded teeth increased.

In this work, the process of “Detente Instantanee Controlee”: DIC (French for Instant controlled pressure drop) assisted to ethanol solvent extraction of phenolic compounds of olive ( Olea europaea ) leaves was studied. Response surface methodology (RSM) was used to optimize the conditions of solvent extraction carried out on the raw material, as well as the operating parameters DIC texturing taking place as pretreatment; both for getting the highest extraction yields of total phenolic compounds (TPC). The studied parameters were the ethanol concentration in the aqueous solution ( S ), the temperature ( T ) and the liquid/solid ratio ( r ). The maximum yield was 49.84 mg GAE per g of dry raw material, and the optimal conditions were: 95.6% EtOH, 55 °C and 40 ml g −1 dm. Under these optimal solvent extraction conditions of the polyphenols extraction, RSM was also used for optimizing DIC treatment. The total phenolic compounds yield of dry DIC-textured material was higher than that of untreated material with an optimized value of 248.6 mg GAE g −1 at the following conditions: saturated steam pressure: P = 0.1 MPa, number of cycles C = 1 and thermal treatment time t = 11 s. Ultra Performance Liquid Chromatography analysis (UPLC) of the treated and untreated olive leaf extracts revealed that the principal polyphenols were oleuropein, verbascoside, luteolin-7-glucoside and smaller amounts of hydroxytyrosol, apigenin-7-glucoside, tyrosol, vanillic acid and vanillin. Scanning electron microscopy (SEM) showed that, after DIC treatment, there is a change in the structure of olive leaves cells with a destruction of cell walls in comparison with untreated leaves.

The present work examined the effect of air drying conditions on drying kinetics of cactus/brewer's grains mixture fermented with Lactobacillus plantarum HG328248. The drying kinetics was performed in a convective dryer for three air temperatures (40, 50 and 60 °C) and three air velocities (0.7, 1.0 and 1.3 m/s). Four mathematical models were tested to fit the drying curves. The Page model seemed the most appropriate to describe experimental data. The experimental drying curves showed two periods: that at constant rate and that of falling rate. The air temperature was the main factor in controlling the drying rate. The characteristic drying curve equation was determined. The influence of air drying conditions on color, water activity and microbiological quality of the fermented product was also studied. The temperature affected these parameters more significantly than air velocity. All dehydrated products had a satisfactory microbiological quality and consequently could be introduced in ruminant feed.

The aim of this work is to investigate the phytochemical composition and functional properties of the melon peels, considered as a by-product. Melon peels (maazoun cultivar) are rich in nutritional ingredients such as carbohydrates (69.77%) and ash (3.67%). They contain significant amounts of total dietary fibers (41.69%) and antioxidants as polyphenols and flavonoids (332mg/100g extract and 95.46mg/100g extract, respectively). The identification and the quantification of the phenolic compounds of melon peels were performed by high performance liquid chromatography apparatus. The obtained results indicate that hydroxybenzoic acids and flavones constitute their main phenolic classes. 3-Hydroxybenzoic acid is the major phenolic compound in the melon peels by 33.45mg/100g, followed by apigenin-7-glycoside (29.34mg/100g). Determination of the functional properties (water and oil retention capacities) and color shows that melon peels have properties that may be useful in industrial applications.

In this study, olive leaves, which are known for their therapeutic and antioxidant properties, were used to assess the effect of solar drying conditions (temperature and flow rate) on the drying time and quality parameters of olive leaves. Samples were dried at three drying temperatures (40, 50 and 60 °C) and at two drying air flow rates (1.62 and 3.3 m 3 min ―1 ) in a convective laboratory solar dryer. From the experimental results, it was noted that the drying time required to reduce the moisture content to 0.10 kg kg ―1 d.b. depends mainly on the drying temperature. The quality attributes of the dehydrated olive leaf samples were investigated in term of colour, total phenols and radical scavenging activity. The effect of solar drying on L* , a * b * parameters was significant (P < 0.05) for all the studied olive leaves. Besides, the total phenols of olive leaves were significantly (P < 0.05) influenced by drying air conditions and tended to decrease with increased drying time. The DPPH radical scavenging activity was higher in fresh [EC 50 39.40 (ZR)-39.95 (CH)] than in dried leaves. However, the radical scavenging activity was also high in leaves dried at 60 °C, 3.3 m 3 min ―1 [EC 50 54.21 (ZR)―68.79 (CL)].

The objectives of this work are to study the effect of salting time, salt concentration and temperature on moisture and salt transfers within Sardinella aurita fillets. Temperature rise as well as brine concentration increase (from 5 to 20 °C and from 15 to 26.5% NaCl, respectively) accelerated water exudation and salt diffusion in the sardine fillets. Salt and moisture apparent diffusivities evolution as a function of concentration were determined by a mathematical treatment without fixing any mathematical relationship between values of diffusivity and concentration. Moisture apparent diffusivity increased from 2.40 × 10−10 to 1.90 × 10−8 m2/s with fillets moisture content increase (from 0.35 to 3.00 g/g db, i.e. 25.9–75% w/w). For a salt content range from 0.16 to 12.80 g NaCl/100 g water, salt apparent diffusivity was relatively constant. Hence, sardine fillets water diffusivity is more related to moisture content than salt diffusivity to brine concentration.

Desorption isotherms of sardine muscles were determined at three temperatures (25, 35 and 50 °C) for a water activity range varying from 0.10 to 0.75. Gravimetric static methods using saturated salt solutions were used (continuous and discontinuous measurements). Six models were taken from the literature to describe experimental desorption isotherms. The OSWIN model shows the best fit of the experimental data. The net isosteric heat of desorption and the isosteric heat of desorption were determined by using the CLAUSIUS–CLAPEYRON equation. The isosteric heat of desorption decreases continuously with the increase of the equilibrium moisture content. A mathematical correlation was established between the isosteric heat of desorption and equilibrium moisture content.

Moisture sorption isotherms are valuable tool for prediction of the stability and shelf-life of agricultural products. The aims of this work were to determine sorption isotherms of four varieties of olive leaves and to compare the experimental and calculated results by using models available in the literature. The equilibrium moisture contents of olive leaves were measured using the static gravimetric method, at water activities and temperatures ranging from 0.058 to 0.898 and from 30 to 50 °C, respectively. Seven models were applied for analysing the experimental data: Guggenheim-Anderson-de Boer, modified Oswin, Henderson-Thompson, White and Eiring, Peleg, Smith and Caurie models. The desorption and adsorption data were best fitted by the Peleg model. Thus, this model can be used for the estimation of the equilibrium moisture contents of olive leaves in the investigated ranges of temperature and water activity. The net isosteric heats of desorption and adsorption of olive leaves were calculated by applying the Clausius–Clapeyron equation to the sorption isotherms and an expression for predicting these thermodynamic properties was developed.

Experimental drying curves of sardine muscles ( Sardinella aurita ) in parallelepiped form were performed under different drying air conditions (three air temperatures: 35, 40 and 50 °C ± 1 °C, two air velocities: 1 and 2.5 m s −1 , and at atmosphere humidity). A diffusive three-dimensional model was established to describe drying of sardine sample in parallelepiped form. The calculated drying curves was compared to the experimental ones in order to determine apparent moisture diffusivity. An empirical equation describing the apparent moisture diffusivity within the sardine muscles was suggested versus temperature and local moisture content of the product. A good agreement was found between experimental and calculated drying kinetics.

Dry salting and wet salting in 21% brine solution of sardine ( Sardinella aurita ) were carried out at 20 °C. Drying of salted fish were run at 40 °C, 15% RH and 1.5 m/s. Salting method affected salt uptake and water loss during salting. Drying experiments showed two falling drying periods; no constant rate period was observed. Drying rate during the first falling period was affected by salting method. Models for salting and drying processes were tested.

Drying of lightly salted sardine (Sardinella aurita) was accomplished using three air temperatures (35°C, 40°C, 50°C) and three air velocities (0.5 m/s, 1.5 m/s, 2 m/s); the effects of drying conditions on drying kinetics were studied. As for all biological products, air temperature is the main factor influencing the drying kinetics. However, over a given temperature which seems to correspond to protein modification (50°C), and at a high air flow rate (2 m/s and 2.5 m/s) a crust formation on the surface of the fish, due to the combined effect of heat and salt was observed. This phenomenon inhibited the drying rate. From the drying curves, two falling rate periods were observed. The dimensionless drying rate versus a dimensionless moisture content data were regressed by the Marquardt Levenberg non-linear optimization method to obtain an empirical equation describing the salted sardine characteristic drying curve.

The paper deals with sorption isotherms and drying kinetics of Eucalyptus globulus. The sorption isotherms have been determined using a static gravimetric method and then fitted by GAB equation at T = 30, 40, and 50°C over a range of relative humidity from 0.05 to 0.9. The drying kinetics in a solar dryer with an auxiliary heating system are determined. The results show with good reproducibility that temperature is the main factor in controlling the drying rate. The drying rate equation is determined empirically from the characteristic curve of drying.

This work presents a chemical (the minerals, chlorophyll contents and fatty acids) and thermophysical investigation (DSC profile) of four varieties of olive leaves grown in Tunisia. The total chlorophy1l contents of olive leaves ranged from 1132.33 to 1795.93 ppm. The results showed that linolenic acid (C 18:3 ) is the major fatty acid in olive leaves (from 30.02 to 42.16%), followed by oleic acid (C 18:1 ) and palmitic acid (C 16:0 ). The thermal profiles of olive leaf extracts determined by their DSC melting curves revealed simple thermograms with a single peak after melting. The hexane extract of the Chemchali variety, which contained relatively high unsaturated fatty acids and low saturated fatty acid levels, exhibited the lowest peak temperature value (54.59 °C) and required the smallest amount of energy for melting (31.57 J·g −1 ). This study showed that olive leaves possessed physicochemical properties and a fatty acid composition that may become interesting for industrial applications.