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This study highlights the possibility of using brewers’ grains (BSGs) for the successive extraction of the main lignocellulosic biopolymers, namely, cellulose, hemicelluloses and lignin. An exhaustive chemical characterisation revealed a variability of composition in distinct batches of BSGs, depending on their origin and the brewing process used. In particular, the protein content can vary from 13wt% to 23wt%, which is accompanied by a change in the hemicelluloses content from 9% to 23% (in the samples of our study). By applying a two-step aqueous treatment, involving an acid (1.25% v/v aq. H2SO4) and a base (3% w/v aq. NaOH) at a temperature of 120°C and fixed reaction time of a few tens of minutes (15–90 minutes), more than 80% of hemicelluloses could be recovered. Cellulose could be isolated at more than 68%, while a high purity lignin could be recovered from a lignin-rich fraction (70wt%). Our work also suggests that the variability of the chemical composition of these BSGs is a hindrance to achieving process standardisation and large-scale exploitation. The pooling of various materials is therefore not a recommended option, and the preliminary chemical analysis of the composition is therefore a prerequisite for an efficient extraction process.

In the present study, leaves from 13 sweet potato cultivars were collected as raw materials. The nutritional and functional composition, antioxidant activity, and sunscreen activity of different sweet potato leaf samples were determined, and the comprehensive nutritional quality was calculated by gray relational analysis. Results showed that the nutritional and functional components are significantly different between different cultivars. Tainong71 showed the highest comprehensive nutritional quality, followed by Fu22, Ningcai, Fu23, Ecai10, Zhecai726, Ecai1, Fu18, Pushu53, Guangcai5, Shulv1, Guangcai2, and Zhecai1. The antioxidant activity varied from 3.94 to 16.75 g Trolox equivalent/100 g dry weight. Pushu53 showed the highest sunscreen activity, with the sun protection factor 24.65. There was a positive correlation between antioxidant activity and sunscreen activity (r = .737, p = .004). In conclusion, sweet potato leaves possess high nutritional and functional properties, and have the huge potential to be used as green leafy vegetables and sunscreen agent.

Lignin is the primary contributor to the high cost of biofuel-production from lignocellulosic biomass. In order to study lignin removal and the release of aromatic monomers, we applied hydrocracking and ionic liquid pretreatments on Arabidopsis thaliana biomass from both wild type (WT) and a mutant (CAD cxd) defective in two cinnamyl alcohol dehydrogenase genes involved in the lignin biosynthetic pathway. For Arabidopsis WT, our results highlight that pretreatments reduce average molecular weight of lignin by about 65% and decrease the content of β-O-4 linkages between lignin monomers. For Arabidopsis CAD mutant, an opposite effect is evidenced. Fewer differences were observed on depolymerization and molecular structure of lignin, which indicates that (8-O-4), (8-5), and (8-8) linkages observed in CAD mutant make lignin more resilient to pretreatment than wild-type lignin. Finally, our study shows the potential of hydrocracking pretreatment technology for extracting valuable aldehyde monomers such as vanillin and syringaldehyde from biomass.

Smart films were produced with ulvan extracted from the green seaweed Ulva. lactuca at different extraction conditions, by varying the glycerol or sorbitol in specific plasticizer concentration. Chemical composition and molecular weight characteristics of ulvans were carried out by GLC and HPSEC analysis, respectively. Regardless of the extraction procedure, the investigation revealed that ulvans were selected as reproducible and suitable materials of stimuli-responsive due to its peculiar chemical composition and self-aggregation molecular behavior. When using the terminology of stimuli-responsive system, we declare that the physico-chemical, barrier, optical, and mechanical characteristics of ulvan films system are strongly responsive to extraction conditions and to plasticizer type and concentration. As plasticizer concentration increased, thickness, moisture content (MC), water solubility, water vapor permeability (WVP), transparency, elongation at break (EAB), usually UV and visible light protection of ulvan films increased, while, their tensile strength (TS) decreased significantly. The films prepared with glycerol exhibited better solubility, transparency and mechanical properties, than those with sorbitol. However, the films formed with sorbitol had the greatest moisture resistance and more effective vapor, visible and UV light barrier as well as the lowest solubility. The FTIR spectra evidenced the expected outcome of the chemical interaction and miscibility kind between polysaccharides and plasticizers.

Quinoa is an excellent source of nutritional and bioactive components. Protein is considered a key nutritional advantage of quinoa grain, and many studies have highlighted the nutritional and physicochemical properties of quinoa protein. In addition, quinoa protein is a good precursor of bioactive peptides. This review focused on the biological properties of quinoa protein hydrolysate and peptides, and gave a summary of the preparation and functional test of quinoa protein hydrolysate and peptides. A combination of milling fractionation and solvent extraction is recommended for the efficient production of quinoa protein. The biological functionalities of quinoa protein hydrolysate, including antidiabetic, antihypertensive, anti-inflammatory, antioxidant activities, and so on, have been extensively investigated based on in vitro studies and limited animal models. Additionally, bioinformatics analysis, including proteolysis simulation, virtual screening, and molecular docking, provides an alternative or assistive approach for exploring the potential bioactivity of quinoa protein and peptides. Nevertheless, further research is required for industrial production of bioactive quinoa peptides, verification of health benefits in humans, and mechanism interpretation of observed effects.

This study deals with the comprehension of lignin partition in biphasic systems constituted of an alkaline aqueous phase containing dissolved lignin and a non-miscible alcohol phase. The main parameters studied are the botanical origin of lignins (softwood/hardwood/herbaceous), the solvent (n-butanol/n-pentanol/n-octanol) and the pH (12, 9.5, 7, 3.5). Lignin concentration is measured by UV spectroscopy to calculate partition coefficients. Lignin migration is driven by the protonation of hydroxyl phenolates at pH 12–9.5 and of carboxylates at pH 7–3.5. FTIR spectra revealed various functional groups in migrated fractions as well as their change in conformation. Notably, hydrogen bonding capacity within its chemical groups and with neighboring fragments and solvents are discussed. NMR results suggest a possibility to adjust separation conditions to tune the lignin composition including the G/S ratio and the content in specific structures (resinol, ferulate, and carbohydrate). GPC highlights a wide diversity of polymers of low molecular weight migrating at basic pH whereas increasing high molecular weight is correlated with aqueous phase acidification. The lignins seem to migrate according to similar structural features whatever the botanical origin, leading to very similar polymer distributions under given conditions. In general, butanol appears to be less selective and is able to solubilize a wide range of lignin polymers independent of the origin. This work provides valuable information regarding the separation of homogeneous lignin fractions enabling standardization of the chemical and physical properties of the lignins to increase their value and the numerous potential applications as a sustainable material.

The inclusion of fibre-rich ingredients in diets is one possible strategy to enhance intestinal fermentation and positively impact gut ecology, barrier and immunity. Nowadays, inulin-type fructans are used as prebiotics in the feed of piglets to manipulate gut ecology for health purposes. Likewise, some by-products could be considered as sustainable and inexpensive ingredients to reduce gut disorders at weaning. In the present study, chicory root and pulp, citrus pulp, rye bran and soya hulls were tested in a three-stepin vitromodel of the piglet’s gastro-intestinal tract combining a pepsin-pancreatin hydrolysis (digestion), a dialysis step using cellulose membranes (absorption) and a colonic batch fermentation (fermentation). The fermentation kinetics, SCFA and microbiota profiles in the fermentation broth were assessed as indicators of prebiotic activity and compared with the ones of inulin. The immunomodulatory effects of fermentation supernatant (FS) were investigated in cultured intestinal porcine epithelial cells (IPEC-J2) by high-throughput quantitative PCR. Chicory root displayed a rapid and extensive fermentation and induced the second highest butyrate ratio after inulin. Citrus pulp demonstrated high acetate ratios and induced elevatedClostridiumclusters IV and XIVa levels. Chicory root and pulp FS promoted the intestinal barrier integrity with up-regulated tight and adherens junction gene expressions in comparison with inulin FS. Chicory pulp FS exerted anti-inflammatory effects in cultured IPEC-J2. The novel approach combining anin vitrofermentation model with IPEC-J2 cells highlighted that both chicory root and pulp appear to be promising ingredients and should be considered to promote intestinal health at weaning.

The structural modification and gelation properties of sweet potato protein (SPP) affected by sulfur-containing amino acids (L-cysteine or L-cystine) and high hydrostatic pressure (HHP) were investigated. Additives altered the denaturation temperature and reduced the denaturation enthalpy of SPP. Higher α-helical contents were observed in untreated or HHP-treated SPP with L-cysteine or L-cystine, while β-sheet and random coil structure unit were decreased. FTIR spectra showed a weak absorbance in HHP-treated SPP with L-cysteine and L-cystine. Storage modulus (G′) of untreated or HHP-treated SPP was enhanced by L-cysteine and L-cystine. Textural properties of SPP gels were improved by sulfur-containing amino acids and HHP, especially for L-cysteine. Decrease in T2b relaxation time and increase in A21 proportion peak area by low-field NMR suggested that water bound more closely to SPP molecules in the presence of L-cysteine and L-cystine, and more immobilized water fraction was trapped in SPP gel matrix.

Active films were produced with sulphated polysaccharides “ulvan”, extracted from the green seaweed Ulva lactuca with different extraction procedures, by varying the glycerol or sorbitol plasticizer concentration at 1% and 2% (w/v). The surface charge and glass transition temperature (Tg) of ulvans were carried out by zeta (ζ)-potential and DSC analysis, respectively. The investigation revealed that ulvans were anionic stable polymers and they had great Tg values. Regardless of the extraction procedure, ulvans can give successful films formulations. However, the optical, thermal, structural and antioxidant characteristics of ulvan films were strongly affected by extraction conditions and by the variation of the type and concentration of plasticizer. In general, as plasticizer concentration increased, ferrous chelating activity and compact structure increased as well, while, Tg, lightness and DPPH radical-scavenging activity decreased. Interestingly, the films plasticized with glycerol exhibited better compact structure, more negative temperature of transition, and greater free radical scavenging ability than with sorbitol. However, the films prepared with sorbitol had the highest L* values and chelating ability. The current study revealed a high correlation between zeta (ζ)-potential of ulvans and their Tg (R2 = 0.98), as well as with scavenging activity of ulvan films (R2 = 0.8–0.99).

Background Dietary strategies such as the inclusion of prebiotics have been suggested for modulating intestinal microbiota. In piglets, this strategy could result in a reduction of post-weaning-associated disorders and the use of antibiotics. To date, mainly purified fractions have been tested for their prebiotic effects at weaning while trials of potential health-promoting effects of products and corresponding by-products remain rare. In this study, fructan- and pectin-based ingredients have been tested in a two-step in vitro model for their fermentation kinetics as well as for their short-chain fatty acid production and microbiota profiles in fermentation broth as indicators for their prebiotic activity. Results Chicory root, in contrast to chicory pulp, exhibited an extensive and rapid fermentation similar to inulin and oligofructose, although butyrate levels of root and pulp did not reach those of the purified fractions. Chicory pulp showed higher relative levels of Lactobacillus spp., Bifidobacterium spp., Clostridium cluster IV and butyryl-CoA:acetate-CoA transferase gene abundance compared to chicory root. Sugar beet pulp, orange and citrus by-products displayed extensive gas fermentation patterns, equivalent to those of purified pectin, and revealed an elevated butyrate production compared to purified pectin. Moreover, several orange and citrus by-products displayed significantly higher relative levels of Bifidobacterium spp. in comparison to purified pectin. Conclusions Chicory root and pulp as well as orange and citrus by-products appear to be promising ingredients for piglet diets for modulating intestinal fermentation for health purposes. © 2019 Society of Chemical Industry.

Bio-composites elaboration is limited by poor interfaces between cellulose and polymer matrices and the cellulose degradation. Achieving cellulose grafting with ferulic acid should enhance those resulting bio-composites mechanical properties. Therefore, a cellulose suspension was modified with ferulic acid using laccase under reaction conditions set at 60 °C, acetate buffer pH 5 for 24 h. Grafted cellulose fibrils were extruded in polypropylene-grafted maleic acid (PPgMA) for mechanical properties studies. Even if ferulic acid interacted with cellulose without any enzyme presence, the acid resilience was only detected for cellulose fibres modified with ferulic acid proving the surface grafting. Cellulose fibrillary lengths were unaffected by the enzymatic treatment suggesting a tiny coating. The resulting bio-composites had a Young modulus reduction of 12%. The elongation at maximal stress had 23% improvement, corresponding to a material mechanical resistance. This result was also confirmed by bio-composite elaboration with natural fibres under the same conditions. Ferulic acid and cellulose blends have improved the hardness properties of the resulting bio-composites with PP-PPgMA.

An organosolv pretreatment consisting of an H2SO4/n-butanol biphasic system was designed to separate lignocellulosic biomass in three distinct phases: a cellulose-rich solid residue, hydrolyzed hem...

Two organosolv methods involving Formic acid/Acetic (FA) acid and Sulphuric acid/Ethanol (SE) solvent mixtures were investigated for lignin extraction from banana rachis biomass residues. Different heating methods were also applied during each extraction process, respectively direct conduction heating and microwave heating. The chemical composition and structural features of the extracted lignin fractions were further analyzed by ATR-FTIR, TGA, elemental analysis and 13C NMR methods. SE extraction method showed a higher extraction yield (58.7%) and allowed also to obtain a lignin fraction with higher purity (76.5% Vs 71.0% for FA lignin). In addition, SE extraction method allowed a higher pulp yield which meant a better selectivity for lignin extraction thanks to the microwave heating method. SE lignin also showed a higher thermal stability due to its higher purity and higher density. The higher molecular weight found for FA lignin residues (7622.7g/mol Vs 5957.7g/mol for SEL) was suspected to be due to co-extracted carbohydrate residues bounded to extracted lignin macromolecules. These results allowed us to establish the SE extraction method (Sulphuric acid/Ethanol/water solvent with microwave heating) as effective for lignin extraction from banana rachis straw.

Sterols are a group of molecules found in plants and animals, which have a number of valuable applications. The deodorization residue, referred to as “deodistillate”, was previously considered as a waste but its economical value nowadays increased due to the presence of high concentrations of sterols, tocopherols and other secondary metabolites attractive for the cosmetic, pharmaceutical or food industry. Sterols can be extracted from vegetable oil deodistillate through a variety of physical and chemical separation processes or their combination. Recently, the use of lipase enzymes has been demonstrated to separate sterols more selectively in higher yields and in milder conditions. This article reviews these lipase-assisted sterol extractions and their main advantages and drawbacks in economic and environmental terms.

Steam explosion (SE) is a versatile tool for the pretreatment of lignocellulosic plant 27 materials and the further separation of their main constitutive components, i.e. cellulose, 28 hemicellulose, lignin, etc. In this study, we propose to evaluate the effects of SE 29 treatment on the recovery of secondary metabolites. As a case study, the well-known 30 grape pomace phenolic compounds were considered. Our results demonstrate that the 31 efficiency of the steam explosion in term of yield (900 mg polyphenols per kg of dry 32 grape pomace) was relatively similar to conventional maceration methods in alcoholic 33 media (800 mg/kg). Advantages of SE compared to maceration were highlighted: the 34 process is organic solvent free, destabilize the biomass structure and release insoluble 35 bound phenolic compounds. In addition, it offers the possibility to modulate distinct 36 polyphenols profiles by modifying the process conditions.

Chondroitin sulfate (CS)-calcium complex (CSCa) was fabricated, and the structural characteristics of CSCa and its proliferative bioactivity to the chondrocyte were investigated in vitro. Results suggested calcium ions could bind CS chains forming polysaccharide-metal complex, and the maximum calcium holding capacity of CSCa reached 4.23 %. Characterization of CSCa was performed by EDS, AFM, FTIR, UV, XRD and 1H-NMR. It was found that calcium ions were integrated with CS by binding the sulfate or carboxyl groups. The thermal properties analysis indicated CSCa had a good thermal stability by TGA and DSC. CSCa could interact the calcium-sensing receptor increasing the intracellular calcium ions and influence the cell cycle. The TGF-β1 secretion induced by CSCa could activate the TGF-β/Smads pathway and change the genes associated proliferation expression ultimately leading to the chondrocyte proliferation. This research probably has an important implication for understanding the effect of CSCa on bone care as food supplements.

The conversion of abundant hexoses (e.g. glucose, mannose and galactose) and pentoses (e.g. xylose and arabinose) to 5-hydroxymethylfurfural (5-HMF) and 2-furfural (2-F) is subject to intensive research in the hope of achieving competitive production of diverse materials from renewable resources. However, the abundance of literature on this topic as well as the limited number of studies systematically comparing numerous monosaccharides hinder progress tracking. Herein, we compare and rationalize reactivities of different ketoses and aldoses. Dehydration mechanisms of both monosaccharide types are reviewed regarding the existing experimental evidence. Ketose transformation to furan derivatives likely proceeds through cyclic intermediates and is hindered by side-reactions such as isomerization, retro-aldol reactions and polymerization. Different strategies can improve furan derivative synthesis from ketoses: limiting the presence of water, improving the dehydration rate, protecting 5-HMF and 2-F reactive moieties with derivatization or solvent interactions and extracting 5-HMF and 2-F from the reaction medium. In contrast to ketoses, aldose conversion to furan derivatives is not favored compared to polymerization reactions because it involves their isomerization or a ring contraction. Enhancing aldose isomerization is possible with metal catalysts (e.g. CrCl3) promoting a hydride shift mechanism or with boric/boronic acids promoting an enediol mechanism. This catalysis is however far more challenging than ketose dehydration because catalyst activity depends on numerous factors: Bronsted acidity of the medium, catalyst ligands, catalyst affinity for monosaccharides and their accessibility to several chemical species simultaneously. Those aspects are methodically addressed to support the design of new monosaccharide dehydration systems.

The integration of easily available and under-exploited biomasses is considered a sustainable strategy in biorefining approaches. Mediterranean countries, especially Algeria, Morocco, and Tunisia, offer such under-exploited waste of different origins. This study revealed the chemical composition and phytochemical characteristics of various agri-food side-products, marine residues, and wild grasses collected in the Maghreb region. Results showed that these wastes contained variable proportions of polysaccharides, lignin, constitute molecules (proteins, lipids, and inorganic molecules) and, various secondary metabolites, mainly flavonoids and condensed tannins. Based on this, the Mediterranean waste was divided into three categories. The first category included waste with high lignin content (40 wt%). The second category contained waste with lignin content below 10 wt% and structural carbohydrate content below 50 wt%. Additionally, the waste in this category comprised noticeable amounts of flavonoids and condensed tannins, particularly from thistle, speedwell, and spurge. Finally, the third category included waste with lignin content above 15 wt% and carbohydrate content in the range of 45–55 wt%. The results also showed that the waste in the third category has a chemical composition similar to that of raw materials envisioned for use in European or North American commercial biorefineries. The findings of this study indicate that the biomass waste employed in this study can be used to develop marketable bioproducts and may be a potential raw material for a biorefinery facility.

Microwave-assisted hydrolysis has been widely studied for cellulose fiber isolation, but the influence of reaction conditions and the microwave non-thermal effect are not well clarified. In this study, a series of well-designed experiments were carried out to measure the effects of reaction conditions including temperature, duration and alkali concentration. Compared to the other parameters, temperature was more relevant to the cellulose content in fiber. It could reach the maximum purity of 90.66 % when the temperature was up to 140 °C. Moreover, the existence of non-thermal effect of microwave has been confirmed through extensive determination and characterization of the fibers obtained from parallel controlled experiments conducted with or without microwave assistance. Approximately 50 %–75 % reduction in reaction time or 67 % of that in chemical costs would be realized under microwave with respect to traditional heating hydrolysis. Therefore, this work provides both deep insight and efficiency strategy into the microwave-assisted cellulose isolation.

During the conversion of lignocellulose, phenolic wastewaters are generated. Therefore, researchers have investigated wastewater valorization processes in which these pollutants are converted to chemicals, i.e., lipids. However, wastewaters are lean feedstocks, so these valorization processes in research typically require the addition of large quantities of sugars and sterilization, which increase costs. This paper investigates a repeated batch fermentation strategy with Rhodotorula kratochvilovae EXF7516 and Cutaneotrichosporon oleaginosum ATCC 20509, without these requirements. The pollutant removal and its conversion to microbial oil were evaluated. Because of the presence of non-monomeric substrates, the ligninolytic enzyme activity was also investigated. The repeated batch fermentation strategy was successful, as more lipids accumulated every cycle, up to a total of 5.4 g/L (23% cell dry weight). In addition, the yeasts consumed up to 87% of monomeric substrates, i.e., sugars, aromatics, and organics acids, and up to 23% of non-monomeric substrates, i.e., partially degraded xylan, lignin, cellulose. Interestingly, lipid production was only observed during the harvest phase of each cycle, as the cells experienced stress, possibly due to oxygen limitation. This work presents the first results on the feasibility of valorizing non-sterilized lignocellulosic wastewater with R. kratochvilovae and C. oleaginosum using a cost-effective repeated batch strategy.

Three-dimensional (3D) printing technology is innovatively used in creating customized healthy food for different population groups. This study provided two appropriate food-ink systems with common bean protein extract (CBPE) for the syringe-based 3D food printer (0.5 g of sodium alginate, 6 g of gelatin, and 40 g of CBPE in 100 mL of water) and the gear-based 3D food printer (3.5 g of agar, 0.05 g of xanthan, and 12 g of CBPE in 100 mL of water), respectively. Superfine grinding significantly (p

Banana production in tropical countries generates significant quantity of waste. Biorefinery of food waste biomass into cellulose, hemicellulose, lignin or pectin macromolecules have grown interest in recent scientific literature. In this paper, hemicellulose from banana rachis (Musa cavendish) was extracted by steam explosion at three severity levels (2.97, 3.57 and 3.78) and was further fractionated by graded ethanol precipitation method (15%, 60% and 80%). The recovered hemicelluloses sub-fractions (H1, H2 and H3) were characterized for their chemical composition and structural features by HPSEC, TGA/DTG, FTIR, 1H and 2D NMR techniques. The hemicellulose extraction yield increased with the severity level and treatment duration. The average molecular weight of the extracted hemicellulose macromolecules decreased from H1-60% ethanol hemicellulose sub-fraction with 143 790 g/mol, followed by H3-60% ethanol hemicellulose sub-fraction with 110 841 g/mol and finally H2-60% ethanol hemicellulose sub-fraction with 61 404 g/mol. The H1-60% ethanol hemicellulose sub-fraction extracted during the steam explosion at the lowest severity level showed the largest molecular weight and exhibited rather a high arabinose/xylose ratio and uronic acid content. Structural analysis revealed that hemicellulose from the 60%-ethanol hemicellulose sub-fractions were mainly arabino-glucuronoxylan (AGX). However, chemical analysis also revealed significant contents of co-extracted residual lignin. Although the ethanol fractionation helped at lowering the lignin content in the 60%-ethanol hemicellulose sub-fractions (20.1% in H2-60%, 24.0% in H1-60% and 28.0 in H3-60%) relatively to 80%-ethanol hemicellulose sub-fractions, additional purification step was still required to improve the quality of the extracted hemicellulose sub-fractions (purity and coloration). Nevertheless these results proved that steam explosion was an effective technique for the extraction of high molecular mass AGX hemicellulose macromolecules from banana rachis residues.

Because of their excellent tensile properties, low density, and natural abundance, cellulose-based plant fibers are a sustainable and biodegradable alternative for synthetic fibers in fiber-reinforced composite materials. However, the extraction of plant fibers can be costly and difficult to control because the fibers are enmeshed in a complex network of biopolymers (principally lignin, pectin, and hemicellulose), which serve both to strengthen the fibers and to bind them to their parent organism. It is necessary to extract or degrade these biopolymers to produce fine plant fibers without adversely altering the fibers themselves in the process. In particular, it is important that both the molecular weight and the degree of crystallinity of the cellulose in the fibers be kept as high as possible. This article reviews chemical treatments, which have been used to extract and refine fibers both from purpose-grown fiber crops, such as hemp and flax, and agricultural waste such as coconut husks and pineapple leaves. The treatments are discussed in terms of changes in the mechanical properties and surface chemistry of the fibers.

Due to its variable botanical origin, functionality, reactivity, and heterogeneity, using lignin in industrial application is not an easy task. In the present study, we investigate the effect of lignin fractionation as a simple way for reducing the variability in its properties. Kraft lignin was separated by ultrafiltration membranes in two fractions with a specific molecular weight and the properties of each fraction were characterized through FTIR, XPS, TGA and cone calorimeter test. Lignin fractions display different thermal and combustion behaviors. Thus, the two fractions have been evaluated as flame retardant additives for polylactide (PLA). PLA composites, containing well dispersed lignin (20 wt%), were produced by melt blending in an internal mixer. The thermo-degradant effect of each fraction on PLA during melt processing was investigated by rheological analysis and size exclusion chromatography while the composites thermal stability and fire properties were evaluated using TGA and cone calorimeter test. Results showed that using appropriate lignin fraction enables for obtaining PLA composites presenting enhanced properties

The effects of monovalent (NaCl) and divalent (CaCl2 and MgCl2) salts combined with high hydrostatic pressure (HHP) on structure and gelation properties of sweet potato protein (SPP) were investigated. Surface hydrophobicity and zeta potential of SPP significantly decreased as salts concentration increased. The total amount of sulfhydryl (-SH-) groups in SPP decreased with addition of NaCl, CaCl2 and MgCl2 under HHP, whereas the disulfide bonds (-S-S-) increased from 0.59 to 0.80 and 0.74 μmol/g with addition of 0.1 and 0.2 moL/L of CaCl2 combined with HHP, respectively. The α-helical content of SPP was increased by all three salts, but decreased as salts combined with HHP, while β-sheet content was increased at high ionic strength with HHP, especially in presence of CaCl2 and MgCl2, being increased from 30.40 to 33.45 and 33.55 g/100 g, respectively. The storage modulus (G′) of SPP was enhanced by salts and HHP, even though it decreased at high ionic strength. Textural properties and water holding capacity of SPP gels were improved with salt ions by HHP, being attributed to more bound water.

Sweet potato is one of cheap sources for starch industries worldwide, and exploiting starch wastewater as an alternative protein source is mainly environmental and economic concerns. In this study, the effects of high hydrostatic pressure (HHP; 250, 400, and 550 MPa) on chemical forces, structure, and gelation properties of sweet potato protein (SPP) at pH 3.0, 6.0, and 9.0 were investigated. The values of surface hydrophobicity (Ho) and absolute value of zeta potential of SPP significantly increased from 250 to 550 MPa (p 180 kDa) were observed in SPP after HHP at pH 6.0 and 9.0 by SDS-PAGE. Regarding elastic rheological behaviors, storage modulus (G′) values of SPP were significantly strengthened after HHP treatment. In addition, textural properties and water-holding capacity of gels made from SPP after 250 and 400 MPa at pH 9.0 were significantly improved, and the gels showed a compact and uniform gel network with the contribution of immobilized water fractions. The gel properties exhibited by SPP after HHP treatment at different pH levels, in particular after 400 MPa at pH 9.0, suggested that it could be potential protein resources as new gelling reagent in the food system.

A new enzymatic methodology is herein proposed to measure free asparagine content in wheat grains and to predict their potential for Maillard reaction products. Our model estimates the acrylamide levels generated during the industrial heat treatment of whole-grain wheat based on free asparagine and glucose measurements. We selected fifteen wheat varieties currently grown in Belgium as benchmark for the present study. While conventional chromatographic methods require a long and tedious multi-step sample preparation, the proposed method takes advantage of being simple and quick. Statistical analysis of free asparagine content indicates that selected wheat varieties can be classified into seven content levels from 0.0149% to 0.0216% of the dry matter. Based on our analysis, the varieties KWS Ozon, Benchmark and Pionier appears to be the most suitable for thermal processing (i.e. cooking applications).

The catalytic performances of two different classes of catalysts containing nickel or/and ruthenium as the active sites were studied in the depolymerisation of lignin isolated from Miscanthus × gig ...

Although chondroitin sulfate calcium complex (CSCa) was claimed to have the bioactivity for bone care in vitro, its anti-osteoporosis bioactivity was little reported in vivo. Here, the effects of CSCa on osteoporosis rats were investigated. Results showed that, compared with the osteoporosis rats, CSCa could improve the bone mineral density and microstructure of femur, and change the bone turnover markers level in serum. 16S rRNA sequencing and metabolomics analysis indicated CSCa intervention altered the composition of gut microbiota along with metabolite profiles in ovariectomized rat faeces. The correlation analysis showed some gut microbiota taxa were significantly correlated with osteoporosis phenotypes and the enriched metabolites. Taken together, dietary CSCa intervention has the potential to alleviate the osteoporosis and related symptoms probably involving gut microbiota or the metabolite profiles as demonstrated in rats. This study provides some scientific evidence for the potential effects of CSCa as the food supplement on the osteoporosis.

This study used hawthorn as object to investigate the relation of structural conversion of pectin fractions during heat processing to the ability of inhibiting lipid digestion. Pectin fractions including water-soluble pectin (WSP), chelator-soluble pectin (CSP), and Na2CO3-soluble pectin (NSP) were isolated from hawthorn tissue after heat processing with different time, as well as the dissolved pectin (DSP) in the heating aqueous phase. The structural features of pectin fractions were characterized by degree of methoxylation, neutral sugar composition, and molecular weight (MW) distribution. After 30-min heat processing, the amount of WSP increased from 78 to 111 mg/g dry basis, while those of CSP and NSP decreased, meanwhile certain amount of DSP (68 mg/g dry basis) was generated. During heat processing, a dynamic alteration of pectin fractions involving solubilization and depolymerization occurred. The solubilization mainly happened in CSP and NSP, inducing a shift from water-insoluble pectin to WSP. The depolymerization occurred in homogalacturonan region of WSP, resulting in a formation of DSP. With the increasing heat time, a more pronounced depolymerization appeared in DSP, which resulted in forming a large amount of pectic polysaccharide fragments with small MW. The WSP showed a good rheological behavior and an ability to inhibit lipid digestion, which was higher than those of DSP. The inhibition rate of WSP (0.1% (w/w)) on lipid digestion decreased from 48.5% to 11.2% after 30-min heat processing. The results can provide novel knowledge to better understand the relation between structure and function of pectin in heat processing.

A combined dry and wet fractionation process is proposed to extract faba bean proteins with lower environmental impact. This fractionation process allowed to recover 87% of the total seeds proteins (92% of dehulled seeds proteins). This is achieved through the production of two protein concentrates (54 and 61% protein content w/w DM). After dry fractionation, wet extraction was performed on the protein-depleted fraction. The presented process consumed less energy and 5.5 times less water per kg extracted proteins, compared to traditional one-step wet extractions. Some anti-nutritional factors contents were also evaluated. Equivalent levels of phytic acid (about 11 mg/g), trypsin inhibitor activity (about 13 trypsin inhibition unit/g) and polyphenols (about 6 mg gallic acid equivalent/g) were observed in the 2 protein-rich fractions. These levels are mainly equivalent to those found after usual dry and wet one-step extractions. Significant differences of calcium, iron and zinc contents were observed between the 2 protein-rich fractions, causing a 30 to 50% difference between those fractions in terms of phytic acid/minerals ratio. Antinutritional factors content in the protein-rich fractions are equivalent to levels found in traditional legumes but still higher than existing recommendations.

The present work aims to evaluate the effect of an acid extraction as well as a combined enzymatic-chemical extraction on structural, thermal and antioxidant properties of the sulphated polysaccharide 'ulvan' from the green seaweed Ulva lactuca. Structural characterization by FTIR and NMR spectroscopies showed the typical peaks of ulvan, namely, uronic acids, rhamnose and sulphate. FTIR analysis revealed that the extraction procedures were able to maintain ulvan structure. Despite differences in the extraction procedures, 13C NMR spectra were globally similar, proving a comparable chemical structure of ulvans. A major difference has been observed in signal intensity which reflected the resonance of glucose or xylose. Thermal characterization proved that ulvans were thermally stable until approximately 180°C. Antioxidant properties of ulvans were evaluated in vitro through different antioxidant assays. Ulvan, which is extracted at pH 1.5 and 90°C, exhibited the greatest scavenging activity (IC50=13.56μg/ml) towards DPPH radical. Result indicated that Mw has influenced inhibitory effect on DPPH radical of ulvan. The current study revealed also a high correlation between sulphate contents of ulvans and their reducing power (R2=-0.89) and their metal scavenging activity (R2=0.97). Overall, ulvans have peculiar structural, thermal and antioxidant properties which promote their use in food or pharmaceutical products as natural ingredient.

High-purity cellulose nanofibers were isolated from wheat straw through an environmentally friendly, multistep treatment process that combined steam explosion, microwave-assisted hydrolysis, and microfluidization. The cellulose content of the processed nanofibers increased from 44.81% to 94.23%, whereas the hemicellulose and lignin contents significantly decreased. Scanning electron microscopy revealed the effects of the isolation treatments on fiber morphology and width. Atomic force microscopy was used to observe the changes in the components, surface roughness, and crystallinity of the fibers. Transmission electron microscopy showed long, loose nanofiber bundles that were 10–40 nm wide with an average individual diameter of 5.42 nm. Fourier transform infrared spectroscopy showed that noncellulosic components were effectively removed. X-ray diffraction analysis revealed the improved crystallinity of the processed fibers, as well as the partial crystalline transformation of cellulose I to cellulose II. T...

Tall fescue, a grass currently grown as forage, presents a good potential as a feedstock in the development of biorefining. In this study, combination of steam explosion and an acetic/formic acid “organosolv” pretreatments are applied on raw fescue to optimize lignin extraction yields and obtain specific products. In a first step, fescue is pretreated by steam explosion under severity factors from 1.4 to 4.2. These treatments allow hemicelluloses solubilization and open the lignocellulosic structure. Steam exploded solid residues are then treated with an acetic acid (50%)/formic acid (30%)/water (20%) mixture. Extracted lignins are precipitated and characterized by size exclusion chromatography (SEC), 31P NMR and HSQC NMR. Results show that acetic and formic acids extracted lignins present G, H and S units with ferulate and p-coumarate. Lignin typical linkages identified are of β-O-4 and spirodienone substructures. Combination of steam explosion and acetic and formic acid pretreatments increases extraction yields from 30% to 100%. Moreover, an increase of the steam explosion treatment intensity induces chemical modifications in lignin structure such β-O-4 and spirodienone substructure degradations, increase of free COOH and phenolic OH bonds, decrease of aliphatic OH ferulate and p-coumarate bonds and changes in G/H/S units proportions. Steam explosion intensity affects also lignin molecular weights.

Two fractions of carob galactomannans (GM25 and GM80) were extracted at respectively 25 °C and 80 °C from crude locust bean gum. Those fractions having slightly different chemical structures, previously characterized, were studied for their viscosity properties over a wide range of concentrations: diluted solution, unperturbed state and gel state. For each of the physical properties, links to the chemical fine structure could be established, expanding knowledge on the topic: in dilute solution, GM25 is more soluble in water while GM80 seems to tend to self-association due to its structure as highlighted by intrinsic viscosity measurements ([ η ] GM25 = 9.96 dL g −1 and [ η ] GM80 = 4.04 dL g −1 ). In unperturbed state, initial viscosities η 0 were more important for GM80 fractions at 1% and 2% due to greater hyperentanglements ( η 0(GM80,1%) = 9.9 Pas; η 0(GM80,2%) = 832.0; Pa.s η 0(GM25,1%) = 3.1 Pas; η 0(GM25,2%) = 45.1 Pas). In gel state, hydrogels obtained from GM80 were also stronger (hardness GM80 (2%) = 0.51 N and hardness GM25 (2%) = 0.11 N), suggesting a much more important number of junction areas within the gel network. The findings discussed herein demonstrate the potential for new applications.

Alterations of the gut microbiome have been associated with obesity and metabolic disorders. The gut microbiota can be influenced by the intake of dietary fibres with prebiotic properties, such as inulin-type fructans. The present study tested the hypothesis that obese individuals subjected for 12 weeks to an inulin-enriched v. inulin-poor diet have differential faecal fermentation patterns. The fermentation of cellulose and inulin hydrolysates of six different inulin-rich and inulin-poor vegetables of both groups was analysed in vitro on faecal inocula. The results showed that the microbiota from obese patients who received a fructan-rich diet for 3 weeks produces more gas and total SCFA compared with the microbiota taken from the same individuals before the treatment. Obese individuals fed with a low-fructan diet produce less gas and less SCFA compared with the treated group. The present study highlighted profound changes in microbiota fermentation capacity obtained by prebiotic intervention in obese individuals, which favours the production of specific bioactive metabolites.

Almonds harvesting, along with precleaning, hulling, shelling, and sorting, generate recoverable co-products such as double, malformed, or damaged almonds. The common way that generates more benefit is the extraction of almond oil for food and cosmetic uses. The aim of this study is to compare composition and nutritional value of almond meals of the main varieties from eastern Morocco, Marcona (M), Fournat de Breznaud (FNB), FerragnesandFerraduel (FF) and Beldi a local ecotype (B), during three consecutive crop years (2016-2018). Significant differences were observed, which mainly concern the residual oil in almond cakes and especially their fibres, sugars, and proteins. Differences depend on the quality of the raw material and the effects of the crop year on the variety. Besides, from a nutritional point of view, analysed almond meals still contain significant amounts of residual oil and the major constituents of almond seeds (sugars, fibres, and proteins). The amino acid profile presents eight essential amino acids (Cysteine, Methionine, Isoleucine, Leucine, Phenylalanine, Tyrosine, and Lysine Valine) and the Protein Digestibility Corrected Amino Acid Score (PDCAAS) ranges between 24.78% for (M) and 62.17% for (FF). We conclude the analysed almond meals present interesting nutritional values as a specific ingredient for gluten-free culinary preparations and light foodstuffs.

Bast flax fibers were treated, with or without ultrasound assistance, using a low melting mixture (LMM) composed of lactic acid, d-glucose and water. This LMM treatment affected both lignin and hemicelluloses contents and modified the fibers properties identified as crucial parameters in an industrial context, i.e. coloration, wettability, crystallinity, fibers diameter and chemical composition. Surface chemistry of the fibers were investigated through fluorescent tagged carbohydrates binding modules revealing macromolecular rearrangements responsible of both a fibers crystallinity enhancement and an unexpected hydrophobicity. It has been found that LMM treatments bleach fibers, which is considered a beneficial effect independent of the treatments.

Quinoa protein has been paid more and more attention because of its nutritional properties and beneficial effects. With the development of bioinformatics, bioactive peptide database and computer‐assisted simulation provide an efficient and time‐saving method for the theoretical estimation of potential bioactivities of protein. Therefore, the potential of quinoa protein sequences for releasing bioactive peptides was evaluated using the BIOPEP database, which revealed that quinoa protein, especially globulin, is a potential source of peptides with dipeptidyl peptidase‐IV (DPP‐IV) and angiotensin‐I‐converting enzyme (ACE) inhibitory activities. Three plant proteases, namely papain, ficin, and stem bromelain, were employed for the in silico proteolysis of quinoa protein. Furthermore, four tripeptides (MAF, NMF, HPF, and MCG) were screened as novel promising bioactive peptides by PeptideRanker. The bioactivities of selected peptides were confirmed using chemical synthesis and in vitro assay. The present work suggests that quinoa protein can serve as a good source of bioactive peptides, and in silico approach can provide theoretical assistance for investigation and production of functional peptides., Quinoa protein, especially globulin, is a potential source of bioactive peptides. In silico analysis makes a contribution to the exploration of novel bioactive peptide.

Co-production of chondroitin sulfate (CS) and peptides was realized from the liquid fraction of chicken sternal cartilage subjected to hot-pressure (HP) by membrane combination separation technology. Cartilage was liquefied via the HP treatment at 110 °C (0.07 MPa) and 120 °C (0.1 MPa) for 0.5 − 2.5 h, respectively. The optimized co-production procedure was as follows: enzymolysis temperature, 61.2 °C; the enzyme ratio of trypsin and papain, 1.3:1 (W/W); enzymolysis time ratio, 2:2 (h/h), under which the highest yields of CS and peptides were 18.85% and 67.99%, and the recoveries were 93.63% and 92.69%. The average molecular weight of CS sample was 67.79 kDa. CS sample was confirmed using agarose-gel electrophoresis, and the structure was analyzed by Fourier transform infrared spectroscopy, chromatography and nuclear magnetic resonance. Taken together, HP can be as a pretreatment method to liquefy cartilage for the industrial co-production of CS and peptides with eco-friendly.

In this study, cattle bone collagen peptides (CPs) were applied to prepare peptides-calcium chelate (CPs-Ca), and the physicochemical, structural properties, and stability of the CPs-Ca were characterized. The optimized preparation conditions were determined by single factor test, and the maximum calcium-chelating capacity was 42.70 ± 1.09 μg/mg. Physicochemical analysis indicated that CPs-Ca was a new substance compared with CPs. Structural analysis demonstrated that calcium ions chelated CPs via the sites of carboxyl oxygen, hydroxyl oxygen and amino nitrogen atom. Morphology analysis showed that CPs-Ca aggregated to large particles due to the crosslinking of calcium ions. According to the stability analysis, CPs-Ca was stable in thermal processing and gastrointestinal digestion. The acid environment was the major factor of CPs-Ca dissociation. The findings put forward a scientific basis for preparing a novel calcium supplement and high-value utilization of cattle bone.

Four kinds of water-soluble pectin (WSP) extracted from hawthorn (HWSP), apple (AWSP), peach (PWSP), and carrot (CWSP) were mixed with oil-in-water emulsion to investigate pectin characteristics on lipid digestion under simulated gastrointestinal conditions. All WSPs were comprehensively characterized by the degree of methoxylation, neutral sugar composition, molecular weight and conformational parameters, intrinsic viscosity, the degree of linearity and branching, as well as molecular morphology observation by atomic force microscopy. The results demonstrated these WSPs possessed different structural characteristics. The molecules of HWSP were of small size with extended short and linear main chain, forming a certain amount of aggregations in the solution, while the molecules of PWSP were of large size with long and branched chains, forming intensive network structure. The molecular chains of AWSP and CWSP were both of medium size and tended to be flexible random coils in solution forming extensive entangled structures. The apparent viscosity of HWSP and PWSP solutions were both higher than those of AWSP and CWSP due to the aggregations or network structure. And the solution of PWSP showed better anti-shear ability than that of HWSP due to the strong cross-linking between molecule chains. The inhibitory effect of WSPs on lipid digestion decreased with the following order: PWSP, HWSP, CWSP, AWSP, which can be well related with their rheological property. The pectin with large molecular weight and highly branched chains that resulted in strong intermolecular interaction will possess good inhibitory effect on lipid digestion.

The effect of extraction procedures on chemical composition, structural, antitumor and anticoagulant properties of the sulphated polysaccharide 'ulvan' from the green seaweed Ulva lactuca were investigated. The structural features of ulvans were carried out by FTIR and by one- and two- dimensional 1H and 13C NMR spectroscopic. The ulvans were mainly composed of rhamnose, xylose, and uronic acid. Chemical and spectroscopic analyses demonstrated that ulvans were constituted of (1→4)-β-glucuronic acid, (1→3,4)-α-L-rhamnose-3-sulphate and (1→4)-α-xylose. The extraction procedures effect were observed in chemical structure, Mw and biological activities. Cytotoxic activity of enzymatic-chemical extract on cervical cancer cells (HeLa) (IC50 = 1000 μg/mL) was higher than on normal peripheral blood lymphocytes cells (PBL). Acid extracts promoted to reduce HeLa cells and to grow PBL cells. At high concentrations, acid extracts showed the highest APTT and TT clotting time. Antitumoral and anticoagulant activities of ulvans from Ulva lactuca promote their use as effective therapeutic agent.