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With the increasing emphasis on sustainability and eco-friendliness, a novel biodegradable packaging materials has received unprecedented attention. Nanocellulose, owing to its high crystallinity, degradability, minimal toxicity, and outstanding biocompatibility, has gained considerable interest in the field of sustainable packaging. This review provided a comprehensive perspective about the recent advances and future development of cellulose nanocrystals (CNCs) and cellulose nanofibers (CNFs). We first introduced the utilization of agricultural waste for nanocellulose production, such as straw, bagasse, fruit byproducts, and shells. Next, we discussed the preparation process of nanocellulose from various agricultural wastes and expounded the advantages and shortcomings of different methods. Subsequently, this review offered an in-depth investigation on the application of nanocellulose in food packaging, especially the function and packaged form of nanocellulose on food preservation. Finally, the safety evaluation of nanocellulose in food packaging is conducted to enlighten and promote the perfection of relevant regulatory documents. In short, this review provided valuable insights for potential research on the biobased materials utilized in future food packaging.

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Sustainable agriculture involves adopting best practices in food production to promote environmental and economic sustainability. Its implementation primarily aims to utilise organic residues to increase yield, diversify production, and reduce costs. In this context, the objective of this study was to investigate different substrates for Hypsizygus ulmarius production and, from its residual substrate, to develop formulations for lettuce seedling growth and subsequent greenhouse cultivation. For mushroom production, substrates were prepared from sawdust with the addition of wheat bran, rice bran, soybean meal, and calcite, resulting in four distinct substrate formulations. The spent mushroom substrate (SMS), obtained at the end of cultivation, was used for lettuce seedling production along with the commercial substrate Carolina Soil® and the soil conditioner BacSol®. The top five formulations were selected for transplanting in the greenhouse. Regarding mushroom production, substrates with higher carbon/nitrogen ratios, around 66: 1, resulted in higher yields. For seedling production, SMS showed lower efficiency compared to the commercial substrate Carolina Soil®, which also benefited from the addition of the soil conditioner BacSol®. However, after transplanting lettuce seedlings, the formulation containing SMS showed superior results in almost all evaluated parameters. Therefore, we concluded that despite the inefficiency of using H.ulmarius SMS for lettuce seedling production, it favours the establishment of seedlings in greenhouse cultivation environments.

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In this study, the peels of the yellow passion fruit (Passiflora edulis f. flavicarpa) were used to develop a flour that was evaluated in terms of its physicochemical, microscopic, colorimetric, and granulometric characteristics, its total phenolic compound and carotenoid contents, and its antioxidant capacity. Fourier Transform Infrared (FTIR) spectroscopy measurements were employed to investigate the constituent functional groups, compounds' chemical profiles were assessed by Paper Spray Mass Spectrometry (PS-MS), and the compound's chemical profiles were evaluated by Ultra-Performance Liquid Chromatography (UPLC). This flour presented a light color, heterogeneous granulometry, high carbohydrate, carotenoid, and total phenolic compound contents with high antioxidant capacity. Scanning Electron Microscopy (SEM) showed a particulate flour, which is supposed to contribute to its compactness. FTIR demonstrated the presence of functional groups corresponding to cellulose, hemicellulose, and lignin, constituents of insoluble dietary fiber. The PS-MS analysis suggested the presence of 22 substances, covering diverse component classes such as organic, fatty, and phenolic acids, flavonoids, sugars, quinones, phenylpropanoid glycerides terpenes, and amino acids. This research demonstrated the potential of using Passion Fruit Peel Flour (PFPF) as an ingredient for food products. The advantages of using PFPF comprise the reduction of agro-industrial waste, contribution to the development of a sustainable food system, and increment of food products' functional profile. Moreover, its high content of several bioactive compounds can benefit consumers' health.

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The Brazil nut shell was used as a precursor material for preparing activated carbon by chemical activation with potassium hydroxide. The obtained material (BNSAC) was characterized, and the adsorptive features of phenol were investigated. The characterization showed that the activated carbon presented several rounded cavities along the surface, with a specific surface area of 332 m2 g-1. Concerning phenol adsorption, it was favored using an adsorbent dosage of 0.75 g L-1 and pH 6. The kinetic investigation revealed that the system approached the equilibrium in around 180 min, and the Elovich model represented the kinetic curves. The Sips model well represented the equilibrium isotherms. In addition, the increase in temperature from 25 to 55 °C favored the phenol adsorption, increasing the maximum adsorption capacity value (qs) from 83 to 99 mg g-1. According to the estimated thermodynamic parameters, the adsorption was spontaneous, favorable, endothermic, and governed by physical interactions. Therefore, the Brazil nut shell proved a good precursor material for preparing efficient activated carbon for phenol removal.

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Promoting the use of renewable energy sources has become an important policy strategy for mitigating climate change and for providing better energy security and financial sustainability. To overcome the problems generated by non-renewable energy sources, it is essential to use new energy sources. A literature review was conducted to investigate and understand the opportunities for implementing new renewable energy sources. Agricultural residues have great potential to receive significant consideration worldwide as an alternative, sustainable, and green energy source. The use of agricultural residues for bioenergy generation is a broad and favourable scenario for exploration. This review identified potential and almost unexplored research approaches with the aim of contributing and promoting researchers to deliver technological solutions for the society and industrial sectors. For example, a potentially promising technological solution would be for industries that produce machinery and agricultural implements to adapt their harvesters for different grain crops, to collect these agricultural residues simultaneously during harvest and readily perform granulation, compaction (pressing), pelletizing or briquetting directly on the property. Further studies are required to investigate the use of agricultural residues for bioenergy generation, which can contribute to the diversification of the energy matrix. Accordingly, in this review, several challenges and future research perspectives have been presented, such as suggestions for future research on how to collect, transport, process, market and use these agricultural residues to generate bioenergy, aiming at reducing the dependence on fossil fuels.

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The removal of copper ions, from synthetic solutions, using walnut shell and olive pomace waste as biosorbents was studied. Synthetic copper solutions were used, and the contact time, initial pH, biosorbent dose, and initial concentration of copper ions were evaluated. The used particle size of both biosorbents was inferior to 600 µm. In the elimination of copper ions, the walnut shell reached 88% (30 min), and the olive pomace 86.5% (40 min). The maximum removal of copper ions was at pH 5 with both biosorbents. The elimination of copper ions was constant with increasing doses of bio-sorbent; however, a decrease close to 90% in the biosorption capacity was determined, when the dose of biosorbent increased from 1 to 10 g/L. The effect of the biosorption capacity increased proportionally with the initial concentration of copper ions; achieving biosorption of 8.3 and 12.9 mg of Cu+2/g of biosorbent, with walnut shell and olive pomace, respectively. Both biosorbent allowed copper ions removal close to 90%; however, to the olive pomace was not necessary a size reduction and had a higher copper ions biosorption capacity than the walnut shell.

RESUMEN: Se estudió la remoción de iones cobre desde solución sintética, usando cáscara de nuez y orujo de oliva como biosorbentes; se evaluó el tiempo de contacto, pH inicial, dosis de biosorbente y concentración inicial de iones cobre. El tamaño de partícula usado de ambos biosorbentes fue inferior a 600 µm. En la eliminación de iones cobre, la cáscara de nuez alcanzó 88 % (30 min) y el orujo de oliva 86,5 % (40 min). La máxima remoción de iones cobre fue a pH 5 con ambos biosorbentes. La eliminación de iones cobre fue constante con dosis crecientes de biosorbente; pero, se determinó una disminución cercana al 90 % en la capacidad de biosorción, cuando la dosis de biosorbente incrementó de 1 a 10 g/L. El efecto de la capacidad de biosorción aumentó proporcionalmente con la concentración inicial de iones cobre; obteniéndose biosorción de 8,3 y 12,9 mg de Cu+2/g de biosorbente, con cáscara de nuez y orujo de oliva, respectivamente. Ambos biosorbentes permitieron una remoción de iones cobre cercana al 90%; sin embargo, el orujo de oliva no necesitó reducción de tamaño y tuvo mejor capacidad de biosorción de iones cobre que la cáscara de nuez.

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Paper and plastic bags have been mainly used in fruit bagging of pineapple production. However, they are often discarded as agricultural wastes after harvest of pineapple fruit and threaten environment. In this study, effects of white non-woven fabric bag, expandable polyethylene bag, black plastic bag and kraft paper bag on fruit quality of pineapple cv. 'MD-2' were investigated. Results showed that fruits with fruit bagging showed no sunburn. When expandable polyethylene bag was used, fruits of pineapple cv. 'MD-2' showed better external qualities, nutrition qualities and texture properties. Expandable polyethylene bag made of degradable and recyclable materials could be recommended as a promising practice to reduce agricultural waste in pineapple production.

Sacos de papel e plástico têm sido usados principalmente no ensacamento de frutas na produção de abacaxi. No entanto, eles são frequentemente descartados como resíduos agrícolas, após a colheita da fruta do abacaxi, e ameaçam o meio ambiente. Neste estudo, os efeitos da sacola de tecido, não tecido branco, sacola de polietileno expansível, sacola plástica preta e sacola de papel artesanal na qualidade do fruto do abacaxi cv. 'MD-2' foram investigados. Os resultados mostraram que as frutas ensacadas não apresentaram queimaduras solares. Quando foi utilizada a bolsa de polietileno expansível, as frutas de abacaxi cv. 'MD-2' mostraram melhores qualidades externas, qualidades nutricionais e propriedades de textura. O saco de polietileno expansível feito de materiais degradáveis e recicláveis pode ser recomendado como uma prática promissora para reduzir o desperdício agrícola na produção de abacaxi.

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ABSTRACT: Paper and plastic bags have been mainly used in fruit bagging of pineapple production. However, they are often discarded as agricultural wastes after harvest of pineapple fruit and threaten environment. In this study, effects of white non-woven fabric bag, expandable polyethylene bag, black plastic bag and kraft paper bag on fruit quality of pineapple cv. 'MD-2' were investigated. Results showed that fruits with fruit bagging showed no sunburn. When expandable polyethylene bag was used, fruits of pineapple cv. 'MD-2' showed better external qualities, nutrition qualities and texture properties. Expandable polyethylene bag made of degradable and recyclable materials could be recommended as a promising practice to reduce agricultural waste in pineapple production.

RESUMO: Sacos de papel e plástico têm sido usados principalmente no ensacamento de frutas na produção de abacaxi. No entanto, eles são frequentemente descartados como resíduos agrícolas, após a colheita da fruta do abacaxi, e ameaçam o meio ambiente. Neste estudo, os efeitos da sacola de tecido, não tecido branco, sacola de polietileno expansível, sacola plástica preta e sacola de papel artesanal na qualidade do fruto do abacaxi cv. 'MD-2' foram investigados. Os resultados mostraram que as frutas ensacadas não apresentaram queimaduras solares. Quando foi utilizada a bolsa de polietileno expansível, as frutas de abacaxi cv. 'MD-2' mostraram melhores qualidades externas, qualidades nutricionais e propriedades de textura. O saco de polietileno expansível feito de materiais degradáveis e recicláveis pode ser recomendado como uma prática promissora para reduzir o desperdício agrícola na produção de abacaxi.

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The main purpose of this work was to use pineapple crowns as substrate for optimizing laccase production by Trametes versicolor in lab-scale experiments. One-factor-at-the-time analysis and response surface methodology were used to optimize production. A single laccase with molecular weight of 45 kDa was the main protein produced. A maximal laccase activity of 60.73 ± 1.01 U/g was obtained in 7-day cultures, representing a 6.7-fold increase compared to non-optimized conditions. The optimized conditions were temperature: 28 °C; initial moisture: 90%; glucose: 8.38%; yeast extract: 2.86%. Combining activity and stability, the best conditions for using this laccase during the long periods required by large-scale processes are pH 4.0-5.0 and temperature of 40-50 °C. Under these conditions, the crude laccase was efficient in detoxifying the dye malachite green with a KM of 14.33 ± 1.94 µM and a Vmax of 0.482 ± 0.029 µM/min with 0.1 units/mL. It can be concluded that pineapple crown leaves can be effectively used as substrate by T. versicolor for producing laccase under solid-state culture conditions. Laccase is an industrially relevant enzyme and its production with concomitant valorization of pineapple crowns as substrate offers highly interesting perspectives.

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The peel of jabuticaba, a small fruit native to Brazil, has been shown to be a potential source of antioxidants and soluble dietary fibers. In this study, flours prepared from these peels were evaluated as a source of pectin. Different extraction methods were employed: ultrasound (US) extraction followed by low temperature heating (40 °C); in a microwave (MW) without (method 1) or with cellulase (method 2) or hemicellulase (method 3); or in a water bath (method 4). Pectin yields ranged from approximately 18% for methods 1 and 4 up to 22% for enzyme-assisted extractions (methods 2 and 3). Methods that did not employ enzymes resulted in low amounts of methoxyl pectins, as opposed to high amounts of methoxyl pectins obtained after enzyme treatment. Cyanidin-3-O-glucoside (C3G) and ellagic acid were the main phenolic compounds found in jabuticaba peel pectins, with higher C3G levels obtained with enzyme-free extraction (methods 1 and 4). All pectins from jabuticaba peel presented a reddish tone, good emulsifying properties and high swelling capacity. The pectin extracted using US+MW+cellulase (method 2) presented better emulsifying performance (higher values of emulsifying activity and emulsion stability), more effective than commercially available citrus pectin.

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The valorization of agri-food by-products is essential from both economic and sustainability perspectives. The large quantity of such materials causes problems for the environment; however, they can also generate new valuable ingredients and products which promote beneficial effects on human health. It is estimated that soybean production, the major oilseed crop worldwide, will leave about 597 million metric tons of branches, leaves, pods, and roots on the ground post-harvesting in 2020/21. An alternative for the use of soy-related by-products arises from the several bioactive compounds found in this plant. Metabolomics studies have already identified isoflavonoids, saponins, and organic and fatty acids, among other metabolites, in all soy organs. The present review aims to show the application of metabolomics for identifying high-added-value compounds in underused parts of the soy plant, listing the main bioactive metabolites identified up to now, as well as the factors affecting their production.

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Cocoa pod husks are a waste generated during the processing of cocoa beans. We aimed to explore the enzymatic extraction of pectin using cellulases. The extraction process was optimized using a central composite design (CCD) and analyzed by response surface methodology (RSM). The parameters optimized were feedstock concentration (%), enzyme dosage (µL/g), and time (h). Three dependent variables were studied: pectin yield (g/100 g dry husk) (R2 = 97.02), galacturonic acid content (g/100 g pectin) (R2 = 96.90), and galacturonic acid yield (g/100 g feedstock) (R2 = 95.35). The optimal parameters were 6.0% feedstock concentration, 40 µL g-1 of enzyme, and 18.54 h, conditions that produced experimentally a pectin yield of 10.20 g/100 g feedstock, 52.06 g galacturonic acid/100 g pectin, and a yield 5.31 g galacturonic acid/100 g feedstock. Using the chemical extraction method, a yield of 8.08 g pectin/100 g feedstock and a galacturonic acid content of 60.97 g/100 g pectin were obtained. Using assisted sonication, a pectin yield of 8.28 g/100 g feedstock and a galacturonic acid content of 42.77 g/100 g pectin were obtained. Enzymatically optimized pectin has rheological and physicochemical features typical of this biomaterial, which provides an interesting alternative for the valorization of cocoa husks.

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BACKGROUND: The production of agricultural wastes still growing as a consequence of the population growing. However, the majority of these residues are under-utilized due their chemical composition, which is mainly composed by cellulose. Actually, the search of cellulases with high efficiency to degrade this carbohydrate remains as the challenge. In the present experiment, two genes encoding an endoglucanase (EC 3.2.1.4) and ß-glucosidase (EC 3.2.1.21) were overexpressed in Escherichia coli and their recombinant enzymes (egl-FZYE and cel-FZYE, respectively) characterized. Those genes were found in Trabulsiella odontermitis which was isolated from the gut of termite Heterotermes sp. Additionally, the capability to release sugars from agricultural wastes was evaluated in both enzymes, alone and in combination. RESULTS: The results have shown that optimal pH was 6.0 and 6.5, reaching an activity of 1051.65 ± 47.78 and 607.80 ± 10.19 U/mg at 39 °C, for egl-FZYE and cel-FZYE, respectively. The Km and Vmax for egl-FZYE using CMC as substrate were 11.25 mg/mL and 3921.57 U/mg, respectively, whereas using Avicel were 15.39 mg/mL and 2314.81 U/mg, respectively. The Km and Vmax for cel-FZYE using Avicel as substrate were 11.49 mg/mL and 2105.26 U/mg, respectively, whereas using CMC the enzyme did not had activity. Both enzymes had effect on agricultural wastes, and their effect was improved when they were combined reaching an activity of 955.1 ± 116.1, 4016.8 ± 332 and 1124.2 ± 241 U/mg on corn stover, sorghum stover and pine sawdust, respectively. CONCLUSIONS: Both enzymes were capable of degrading agricultural wastes, and their effectiveness was improved up to 60% of glucose released when combined. In summary, the results of the study demonstrate that the recombinant enzymes exhibit characteristics that indicate their value as potential feed additives and that the enzymes could be used to enhance the degradation of cellulose in the poor-quality forage generally used in ruminant feedstuffs.

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The bioactive compounds of pequi peel flours were characterized. Flavonoid contents ranged from 19.67 to 87.61 mg/100 g, high in comparison to many vegetables described in the literature. Gallic acid (11.52-418.67 mg/100 g), gallate ethyl (2026.75 - 5205.90 mg/100 g), ellagic acid (509.47 - 1630.66 mg/100 g), lutein (0.17-1.36 mg/100 g), ß-carotene (0.82 - 1.49 mg/100 g), and ß-cryptoxanthin (0.07 - 0.11 mg/100 g) were identified by HPLC, contributing to a greater valorization of the pequi peel flours. Phytochemical tests indicated the presence of hydrolyzable tannins and saponins. The detection of these compounds makes the product commercially attractive, in addition to generating value for an agro-industrial residue. The results obtained in this study confirm the multifunctional potential of pequi peel flour as a functional ingredient.

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Herein, the biosorption of Cr(VI) by magnetized coconut fibres obtained from agricultural waste has been described. Magnetization was achieved by incorporating magnetite nanoparticles into the fibres by a coprecipitation reaction in alkaline media. The biosorption capacity of the fibres was evaluated by two series of experiments. In the first series, 500 mg L-1 of the biosorbent was added to a 50 mg L-1 K2Cr2O7 solution at 28 °C and stirred at 200 rpm and the pH was varied from 1 to 13 to determine the optimum pH value. The second series of experiments evaluated the sorption capacity of the fibres at the optimum pH, under the same agitation speed and temperature but with an adsorbate concentration of 100 mg L-1. The biosorbents were characterized using Fourier transform-infrared spectroscopy, inductively coupled plasma-atomic emission spectroscopy, scanning electron microscopy, dispersive X-ray fluorescence, and X-ray powder diffraction. The biosorption experiments demonstrated that the magnetization process increased the biosorption capacity of the material. Optimum biosorption occurred at pH 2, and at optimal conditions, the best adsorptive efficiency exceeded 90%, reaching a biosorption capacity of 87.38 mg g-1 for the magnetized fibre and 23.87 mg g-1 for the natural fibre, with an equilibrium time of less than 20 min.

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Energy-driven biorefineries can be designed considering biotechnological and thermochemical conversion pathways. Nevertheless, energy and environmental comparisons are necessary to establish the best way to upgrade lignocellulosic biomass and set the requirements of these processes in different scenarios. This paper aims to evaluate experimentally a biorefinery producing energy vectors using coffee-cut stems (CCS) as feedstock. The obtained yields were the basis for energy and environmental analysis, in two different biorefinery scenarios: (i) production of bioethanol and biogas and (ii) production of syngas and electricity. The energy results indicated that the overall energy efficiency calculated in the first scenario was only 9.15%. Meanwhile, the second biorefinery configuration based on thermochemical routes presented an energy efficiency value of 70.89%. This difference was attributed to the higher consumption of utilities in the biorefinery based on biotechnological routes. The environmental results showed that the impact category of climate change for the first biorefinery (i.e., 0.0193 kg CO2 eq./MJ) had a lower value than that of the second process (i.e., 0.2377 kg CO2 eq./MJ). Thus, the biorefinery based on the biotechnological route presented a better environmental performance. Additionally, the results for both biorefineries allowed concluding that the inclusion of by-products and co-products in the calculation of the environmental analysis can dramatically affect the results.

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Biosorption is a technique widely used in the remediation of contaminated effluents, and its main advantages are its easy applicability, high efficiency rate, versatility, and its economic viability. Associated with nanotechnology, this work proposes the use of nanocomposites of sugarcane bagasse (SB) and ferromagnetic nanoparticles (Fe3O4) in the removal of metallic ions present in contaminated water. SB is a promising adsorbent material since it is an abundant agricultural residue, easily accessed. By using the coprecipitation method, two nanocomposites were obtained from in natura (SB-NP) or acid-treated (MSB-NP) sugarcane bagasse. These materials were synthetized by impregnation of Fe3O4 to gain paramagnetic properties and to facilitate the removal of the contaminant-containing adsorbent. The characterization of the nanocomposites was performed using pHPCZ, FTIR, XRD, and SEM/EDS techniques, to evaluate the synthesis efficiency and investigate the morphology of the materials. The efficiency of magnetite impregnation on the SB was assessed by SEM/EDS and XRD, while the main functional groups (carbonyl, carboxyl, hydroxyl, amine, amide, and nitrate) responsible for adsorption were found by FTIR. In the surface charge characterization by pHPCZ sorption of dyes, it was found that negative charges are predominant. The pHPCZ for SB-NP and MSB-NP was 5.95 and 5.59, respectively, and the chosen Cu(II) adsorption pH was 6.2 ± 0.1. The adsorption equilibrium was reached between 10 and 60 min of contact time. The maximum experimental sorption capacity (SCexp) was 2.53 ± 0.09 (SB-NP) and 2.61 ± 0.01 mg/g (MSB-NP). The isotherm models applied to the experimental data were Langmuir, Freundlich, Sips, Temkin, and Dubinin-Radushkevich, and Temkin best described the adsorption phenomena for Cu(II) by SB-NP (r2 = 0.9976 and χ2 = 3.965) and MSB-NP (r2 = 0.9990 and χ2 = 1.816). Reuse cycles of the nanocomposites were also performed employing ten cycles of sorption using 50 mg/L Cu(II) solutions, after which the materials showed SCexp = 7.47 ± 0.04 mg/g (SB-NP) and 7.82 ± 0.04 mg/g (MSB-NP). Therefore, the investigated materials exhibited promising results to be used as biosorbents in the remediation of effluents contaminated with toxic metal ions, such as copper.

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From an environmental perspective, searching for useful compounds in agri-food by-products by employing inefficient and polluting analytical procedures is paradoxical. This work aimed to develop a green, simplified, and highly efficient experimental setup for extracting and tentatively identifying the broadest range of metabolites in sugarcane solid by-products collected directly within the industrial mills. Nine different extraction approaches were investigated side-by-side, including three reference methods. Based on the extraction and environmental performances assessed by two complementary metrics called Analytical-Eco Scale and the Analytical Greenness Calculator, it was possible to reach two highly efficient two liquid-phase extractions while avoiding harmful solvents and traditional time, energy, and solvent consuming sample preparation steps, such as solvent evaporation, metabolite concentration, re-suspension, and derivatization. The simultaneously produced hydroethanolic and n-heptane extracts were directly analyzed by ultra-high-performance liquid chromatography and gas chromatography, both coupled to mass spectrometry, respectively, leading to the annotation of a large dynamic range of compounds from information rich spectral data. Up to 111 metabolites were identified in a single matrix, from highly polar sucrose to nonpolar wax ester C53 in a single extraction. Orientin, apigenin-6-C-glucosylrhamnoside, 1-octacosanol, octacosanal, and other bioactive compounds were identified in these abundantly available by-products, which are currently just burned to produce energy. The best two methods developed here (Two-Liquid-Phase Ultrasound-Assisted Extraction with Probe and Two-Liquid-Phase Dynamic Maceration) appeared as a green, simplified, and highly efficient procedures to qualitatively profile metabolites in complex solid matrices.

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About 0.5 ton of coffee pulp is generated for each ton of coffee cherry processed. In the present study, this waste was investigated as a source of pectin. Coffea arabica L. pulp was dried, treated with ethanol and the pectin extracted with 0.1 M HNO3 (14.6 % yield). Chromatographic, colorimetric and spectroscopic methods were used for pectin characterization. It had 79.5 % galacturonic acid, high methoxyl content (63.2 %), low levels of acetylation, protein and phenolics and Mw of 3.921 × 105 g/mol. The pectin from coffee pulp was able to form gels with high concentration of sucrose or xylitol and low pH. The effect of pH (1.5-3.0), concentrations of pectin (0.5-2.5 %), sucrose (55-65 %) and xylitol (55-60 %) on the viscoelastic properties was investigated. Gels prepared with xylitol diplayed similar viscoelastic behavior to the gels prepared with sucrose. The results demonstrated that coffee pulp is a potential source of commercial pectin with gelling properties.

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Asphalt self-healing by encapsulated rejuvenating agents is considered a revolutionary technology for the autonomic crack-healing of aged asphalt pavements. This paper aims to explore the use of Bio-Oil (BO) obtained from liquefied agricultural biomass waste as a bio-based encapsulated rejuvenating agent for self-healing of bituminous materials. Novel BO capsules were synthesized using two simple dripping methods through dropping funnel and syringe pump devices, where the BO agent was microencapsulated by external ionic gelation in a biopolymer matrix of sodium alginate. Size, surface aspect, and elemental composition of the BO capsules were characterized by optical and scanning electron microscopy and energy-dispersive X-ray spectroscopy. Thermal stability and chemical properties of BO capsules and their components were assessed through thermogravimetric analysis (TGA-DTG) and Fourier-Transform Infrared spectroscopy (FTIR-ATR). The mechanical behavior of the capsules was evaluated by compressive and low-load micro-indentation tests. The self-healing efficiency over time of BO as a rejuvenating agent in cracked bitumen samples was quantified by fluorescence microscopy. Main results showed that the BO capsules presented an adequate morphology for the asphalt self-healing application, with good thermal stability and physical-chemical properties. It was also proven that the BO can diffuse in the bitumen reducing the viscosity and consequently self-healing the open microcracks.