RESUMEN
This study explores microplastic and cellulosic microparticle occurrences in the NE Atlantic, focusing on the Porcupine Bank Canyon and Porcupine Seabight. Water samples from depths ranging between 605 and 2126 m and Lophelia pertusa coral samples from 950 m depth were analysed. Microparticles were detected in deep-water habitats, with concentrations varying from 2.33 to 9.67 particles L-1 in the Porcupine Bank Canyon, notably lower at greater depths. This challenges the assumption of deeper habitats solely acting as microplastic sinks. We also found evidence of microparticle adsorption and ingestion by L. pertusa. The presence of microparticles in cold-water corals underscores their vulnerability to pollutants. Furthermore, the dominance of rayon microparticles in both water and coral samples raises questions about marine pollution sources, potentially linked to terrestrial origins. This research emphasises the critical need for comprehensive exploration and conservation efforts in deep-sea environments, especially to protect vital ecosystems like L. pertusa reefs.
Asunto(s)
Antozoos , Monitoreo del Ambiente , Microplásticos , Contaminantes Químicos del Agua , Animales , Microplásticos/análisis , Contaminantes Químicos del Agua/análisis , Océano Atlántico , Ecosistema , Celulosa/análisis , Arrecifes de CoralRESUMEN
Efforts are ongoing to utilise agricultural waste to achieve a full resource use approach. Bambara groundnut is an important crop widely grown in the sub-Saharan Africa with potential future importance because of its resilience to thrive under heightened weather uncertainty and widespread droughts that have challenged food security. After harvesting, the edible nuts are separated from the shells which are discarded as waste. Therefore, this research is aimed at characterising the chemical composition and the structural properties of Bambara groundnut shells (BGS) in view of their potential application as a biomass for different bio-products. The chemical composition of BGS was found to be 42.4% cellulose, 27.8% hemicellulose, 13% lignin and 16.8% extractives. Proximate analysis showed a high amount of volatile matter (69.1%) and low moisture (4.4%). XRD analysis confirmed crystallinity of cellulose I polymer and FTIR analysis observed functional groups of lignocellulosic compounds. Thermal stability, maximum degradation temperature and activation energy were found to be 178.5 °C, 305.7 °C and 49.4 kJ/mol, respectively. Compared to other nutshells, BGS were found to have a relatively high amount of cellulose and crystallinity that may result in biocomposites with improved mechanical properties.
Asunto(s)
Biomasa , Vigna , Vigna/química , Lignina/química , Lignina/análisis , Celulosa/química , Celulosa/análisis , Residuos/análisis , Nueces/química , Biocombustibles , PolisacáridosRESUMEN
Food safety and authenticity analysis play a pivotal role in guaranteeing food quality, safeguarding public health, and upholding consumer trust. In recent years, significant social progress has presented fresh challenges in the realm of food analysis, underscoring the imperative requirement to devise innovative and expedient approaches for conducting on-site assessments. Consequently, cellulose paper-based devices (PADs) have come into the spotlight due to their characteristics of microchannels and inherent capillary action. This review summarizes the recent advances in cellulose PADs in various food products, comprising various fabrication strategies, detection methods such as mass spectrometry and multi-mode detection, sampling and processing considerations, as well as applications in screening food safety factors and assessing food authenticity developed in the past 3 years. According to the above studies, cellulose PADs face challenges such as limited sample processing, inadequate multiplexing capabilities, and the requirement for workflow integration, while emerging innovations, comprising the use of simplified sample pretreatment techniques, the integration of advanced nanomaterials, and advanced instruments such as portable mass spectrometer and the innovation of multimodal detection methods, offer potential solutions and are highlighted as promising directions. This review underscores the significant potential of cellulose PADs in facilitating decentralized, cost-effective, and simplified testing methodologies to maintain food safety standards. With the progression of interdisciplinary research, cellulose PADs are expected to become essential platforms for on-site food safety and authentication analysis, thereby significantly enhancing global food safety for consumers.
Asunto(s)
Celulosa , Análisis de los Alimentos , Inocuidad de los Alimentos , Papel , Inocuidad de los Alimentos/métodos , Celulosa/química , Celulosa/análisis , Análisis de los Alimentos/métodos , Contaminación de Alimentos/análisis , Espectrometría de Masas/métodosRESUMEN
Non-centrifugal raw cane sugar (NRCS) is a minimally processed product from sugarcane (Saccharum officinarum L). This product contains phytochemical and nutritional compounds that benefit human health. Despite these advantages, NRCS commercialization is hindered by a lack of knowledge about its composition and, consequently, the absence of quality standards. Studies associating the nutritional composition of sugarcane varieties and their genuine products have not yet been found in the literature, and understanding this relationship can help establish quality standards for this product. Therefore, this study evaluated the mineral nutritional composition of genuine derivative NRCS produced from two sugarcane varieties obtained under different agronomic conditions at two stages of maturation to verify the relationships between raw material and the product. The obtained sugarcanes, juices, and bagasse, as well as the produced sugars, were analyzed for mineral content, such as calcium, magnesium, potassium, phosphorus, sulfur, iron, manganese, copper, and zinc, using inductively coupled plasma optical emission spectrometry. Most mineral constituents of sugarcane are in the juice in direct proportions to those in raw sugarcane. Thus, minimally processed food derivatives have nutritional characteristics equivalent to the raw materials. Consumption of NRCS contributes to meeting daily requirements for essential nutrients such as magnesium, copper, potassium, and manganese. For manganese, 25 g of NRCS, like the one produced in this study, can fulfill 22 to 76 % of an adult male's daily mineral requirements. The variation observed in the four NRCS samples, obtained from the same sugarcane variety under different maturation and agronomic conditions, was 250 %. This variation makes establishing quality parameters for mineral or ash content difficult. Therefore, setting mineral content levels for NRCS is inappropriate, as this parameter naturally depends on the raw material.
Asunto(s)
Minerales , Valor Nutritivo , Saccharum , Saccharum/química , Minerales/análisis , Celulosa/análisis , Celulosa/química , Manipulación de Alimentos/métodosRESUMEN
A non-invasive capacitance instrument was embedded in the base of a vacuum-drying tray to monitor continuously the residual amount of solvent left in a pharmaceutical powder. Proof of concept was validated with Microcrystalline Cellulose laced with water, as well as water/acetone mixtures absorbed in a spray-dried Copovidone powder. To illustrate the role of impermeability of the base, we derive a model of vapor sorption that reveals the existence of a kinetic limit when solids are thinly spread, and a diffusion limit with greatly diminished effective diffusivity at large powder thickness. By monitoring the residual solvent content of powders, this new in situ technique offers advantages over indirect methods like mass spectrometry of vapor effluents, but without complications associated with probe fouling. To prescribe design guidelines and interpret signals, we model the electric field shed by the probe when a powder holds variable solvent mass fraction in the vertical direction.
Asunto(s)
Celulosa , Polvos , Solventes , Solventes/química , Vacio , Celulosa/química , Celulosa/análisis , Pirrolidinas/química , Pirrolidinas/análisis , Compuestos de Vinilo/química , Agua/química , Desecación/métodos , Acetona/análisis , Acetona/química , Difusión , CinéticaRESUMEN
To investigate the correlation between carbon and oxygen isotope compositions of plant cellulose and climatic factors as well as plant physiological indices on the southeastern margin of the Qinghai-Tibet Plateau, we examined plant species in eight sampling sites with similar latitudes and different longitudes in this region. Through the characteristics of δ13C and δ18O values, fractionation values (Δ13C and Δ18O) in leaf cellulose, we discussed water use efficiency (WUE) and the environmental factors, the variation of carbon and oxygen isotopes in the southeastern margin of the Qinghai-Tibet Plateau with elevation and longitude, and revealed the indication degrees of isotopic signals to different environments and vegetation physiology. By using the semi-quantitative model of carbon and oxygen dual isotopes, we investigated the physiological adaptation mechanisms of plants to varying environmental conditions. The results demonstrated that both Δ13C and Δ18O of cellulose decreased with increasing elevation and longitude, and Δ13C was more influenced by longitude, while Δ18O was more susceptible to elevation variation. Additionally, Δ13C and Δ18O were significantly and positively correlated with temperature (TEM), precipitation (PRE), potential evapotranspiration (PET), and relative humidity (RH). PRE was the dominant meteorological factor driving the variation of Δ13C, while RH was the dominant meteorological factor influencing Δ18O variation. In contrast to Δ13C, WUE showed a stronger correlation with elevation than with longitude, which increased as elevation and longitude increased. According to the carbon-oxygen model, plant stomatal conductance (gs) and photosynthetic capacity (Amax) decreased with increasing precipitation and relative humidity, while the values increased with increasing elevation and longitude. The combined analysis of carbon and oxygen isotopes of organic matters would yield additional environmental and gas exchange information for studies on climate tracing and vegetation physiology studies on the southeastern margin of the Qinghai-Tibet Plateau.
Asunto(s)
Isótopos de Carbono , Ecosistema , Isótopos de Oxígeno , Isótopos de Oxígeno/análisis , China , Isótopos de Carbono/análisis , Clima , Altitud , Plantas/metabolismo , Plantas/clasificación , Fenómenos Fisiológicos de las Plantas , Tibet , Celulosa/metabolismo , Celulosa/análisisRESUMEN
Diverse methodologies exist to determine the chemical composition, proximate analysis, and calorific value of biomass. Researchers select and apply a specific methodology according to the lignocellulosic material they study and the budgetary resources available. In this project, we determined the primary chemical constitution and proximate analysis of Prosopis laevigata (Humb. & Bonpl.) Jonhst wood using a traditional chemical method and a novel procedure based on the deconvolution of the DTG signal produced by TGA. The highest calorific value was verified using a calorimetric pump based on mathematical models. We also conducted elemental analysis and a microanalysis of ash, and applied Fourier transform infrared spectroscopic analysis (FT-IR). The means of the results obtained by the chemical method and TGA-DTG, respectively, were: hemicelluloses 7.36%-(8.72%), cellulose 48.28%-(46.08%), lignin 30.57%-(32.44%), extractables 13.53%-(12.72%), moisture 2.03%-(4.96%), ash 1.77%-(1.90%), volatile matter 75.16%-(74.14%), and fixed carbon 23.05%-(18.93%). The procedure with the calorimetric pump generated a calorific value above 20.16 MJ/kg. The range generated by the various models was 18.23-21.07 MJ/kg. The results of the elemental analysis were: carbon 46.4%, hydrogen 6.79%, oxygen 46.43%, nitrogen 0.3%, and sulfur 0.5%. The microanalysis of ash identified 18 elements. The most abundant ones were potassium Ë calcium Ë sodium. Based on the infrared spectrum (FT-IR) of Prosopis laevigata wood, we detected the following functional groups: OH, C-H, C=O, CH2, CH3, C-O-C, C-OH, and C4-OH. Our conclusion is that the TGA-DTG method made it possible to obtain results in less time with no need for the numerous reagents that chemical procedures require. The calorific value of P. laevigata wood is higher than the standards. Finally, according to our results, proximate analysis provides the best model for calculating calorific value.
Asunto(s)
Lignina , Prosopis , Termogravimetría , Madera , Madera/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Prosopis/química , Lignina/química , Lignina/análisis , Biomasa , Celulosa/química , Celulosa/análisis , PolisacáridosRESUMEN
This investigation explored the presence of microplastics (MPs) and artificial cellulosic particles (ACPs) in commercial water marketed in single use 1.5 L poly(ethylene terephthalate) bottles. In this work we determined a mass concentration of 1.61 (1.10-2.88) µg/L and 1.04 (0.43-1.82) µg/L for MPs and ACPs respectively in five top-selling brands from the Spanish bottled water market. Most MPs consisted of white and transparent polyester and polyethylene particles, while most ACPs were cellulosic fibers likely originating from textiles. The median size of MPs and ACPs was 93 µm (interquartile range 76-130 µm) and 77 µm (interquartile range 60-96 µm), respectively. Particle mass size distributions were fitted to a logistic function, enabling comparisons with other studies. The estimated daily intake of MPs due to the consumption of bottled water falls within the 4-18 ng kg-1 day-1 range, meaning that exposure to plastics through bottled water probably represents a negligible risk to human health. However, it's worth noting that the concentration of plastic found was much higher than that recorded for tap water, which supports the argument in favour of municipal drinking water.
Asunto(s)
Agua Potable , Microplásticos , Contaminantes Químicos del Agua , Microplásticos/análisis , Agua Potable/química , Agua Potable/análisis , España , Contaminantes Químicos del Agua/análisis , Celulosa/química , Celulosa/análisis , Humanos , Tamaño de la Partícula , Tereftalatos Polietilenos/química , Tereftalatos Polietilenos/análisisRESUMEN
Since the ingestion of both natural and anthropogenic microfibers produces a deleterious effect on aquatic organisms, it is crucial to explore the emission of these pollutants by WWTPs into the receiving water bodies, such as rivers. Cellulose- and petroleum-based microfibers, as well as microplastic particles, were collected from the effluent of a municipal WWTP operating with activated sludge technology in Budapest, Hungary. During two sampling campaigns organized in February and April of 2023 on different working days and at different times of the day, 123-145 L of effluent was sieved and filtered. The organic matter was removed by hydrogen-peroxide treatment. All fibers and particles larger than 10 µm were counted, and using a fluorescence microscope, the fibers were geometrically characterized in terms of length and diameter. Each fiber was individually identified by transflection-FT-IR method. The fiber concentration varied in the range of 1.88-2.84 and 4.25-6.79 items/L during the 7th and the 16th week of 2023, respectively. In February and April, the proportion of microfibers in the solid particles was 78.3 and 94.7%, respectively. In the effluent the cellulose-based microfibers were dominant (53-91%), while among the petroleum-based microfibers, polyester occurred most often. The median length of cellulose-based fibers was considerably higher in April than in February (650 vs. 1250 µm), and simultaneously the median diameter also increased from 21 to 29 µm. This behaviour was also seen, albeit to a lesser extent, in connection to microfibers derived from petroleum. The treated wastewater's daily microfiber transport to the Danube River varied between 0.44 - 0.69 and 0.94-1.53 billion in February and April 2023, respectively.
Asunto(s)
Aguas Residuales , Hungría , Aguas Residuales/química , Celulosa/análisis , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Purificación del Agua/métodos , Microplásticos/análisis , Eliminación de Residuos Líquidos/métodos , Petróleo/análisis , Aguas del Alcantarillado/análisisRESUMEN
Portable near-infrared (NIR) spectrophotometers have emerged as valuable tools for identifying substandard and falsified pharmaceuticals (SFPs). Integration of these devices with chemometric and machine learning models enhances their ability to provide quantitative chemical insights. However, different NIR spectrophotometer models vary in resolution, sensitivity, and responses to environmental factors such as temperature and humidity, necessitating instrument-specific libraries that hinder the wider adoption of NIR technology. This study addresses these challenges and seeks to establish a robust approach to promote the use of NIR technology in post-market pharmaceutical analysis. We developed support vector machine and partial least squares regression models based on binary mixtures of lab-made ciprofloxacin and microcrystalline cellulose, then applied the models to ciprofloxacin dosage forms that were assayed with high performance liquid chromatography (HPLC). A receiver operating characteristic (ROC) analysis was performed to set spectrophotometer independent NIR metrics to evaluate ciprofloxacin dosage forms as "meets standard," "needs HPLC assay," or "fails standard." Over 200 ciprofloxacin tablets representing 50 different brands were evaluated using spectra acquired from three types of NIR spectrophotometer with 85% of the prediction agreeing with HPLC testing. This study shows that non-brand-specific predictive models can be applied across multiple spectrophotometers for rapid screening of the conformity of pharmaceutical active ingredients to regulatory standard.
Asunto(s)
Ciprofloxacina , Espectroscopía Infrarroja Corta , Comprimidos , Ciprofloxacina/análisis , Ciprofloxacina/química , Comprimidos/análisis , Espectroscopía Infrarroja Corta/métodos , Espectroscopía Infrarroja Corta/normas , Cromatografía Líquida de Alta Presión/métodos , Calibración , Análisis de los Mínimos Cuadrados , Máquina de Vectores de Soporte , Celulosa/química , Celulosa/análisis , Medicamentos Falsificados/análisisRESUMEN
Taro (Colocasia esculenta) flour is a viable carbohydrate alternative and a functional additive for food formulation; however, different taro varieties may possess distinct characteristics that may influence their suitability for food production. This study evaluated the nutritional, physicochemical, and functional properties of flours from five Hawaiian taro varieties: Bun-Long, Mana Ulu, Moi, Kaua'i Lehua, and Tahitian. Tahitian, Bun-long, and Moi had high total starch contents of 40.8, 38.9, and 34.1 g/100 g, respectively. Additionally, Moi had the highest neutral detergent fiber (25.5 g/100 g), lignin (1.39 g/100 g), and cellulose (5.31 g/100 g). In terms of physicochemical properties, Tahitian showed the highest water solubility index (33.3 g/100 g), while Tahitian and Moi exhibited the two highest water absorption indices (5.81 g/g and 5.68 g/g, respectively). Regarding functional properties, Tahitian had the highest water absorption capacity (3.48 g/g), and Tahitian and Moi had the two highest oil absorption capacities (3.15 g/g and 2.68 g/g, respectively). Therefore, the flours from these Hawaiian taro varieties possess promising characteristics that could enhance food quality when used as alternative additives in food processing.
Asunto(s)
Colocasia , Fibras de la Dieta , Harina , Valor Nutritivo , Almidón , Colocasia/química , Harina/análisis , Hawaii , Almidón/análisis , Almidón/química , Fibras de la Dieta/análisis , Solubilidad , Celulosa/química , Celulosa/análisis , Lignina/química , Lignina/análisis , AguaRESUMEN
In response to the prevalent issue of thiram as a common pesticide residue on the surface of fruits and vegetables, our research team employed an acidic hydrated metal salt low co-fusion solvent to dissolve cellulose lysis slurry. Subsequently, a regenerated cellulose membrane (RCM) was successfully prepared via sol-gel method. Uniformly sized Ag nanoparticles (NPs) were deposited on RCM utilizing the continuous ion layer adsorption and reaction (SILAR) technique. The resulting Ag NPs/RCM flexible surface-enhanced Raman spectroscopy (SERS) substrates exhibited a minimum detection limit of 5 × 10-9 M for Rhodamine 6G (R6G), demonstrating good uniformity (RSD = 4.86 %) and reproducibility (RSD = 3.07 %). Moreover, the substrate displayed a remarkable sensitivity of 10-10 M toward thiram standard solution. Given its inherent flexibility, the substrate proves advantageous for the detection of three-dimensional environments such as fruit and vegetable surfaces, and its practicality has been confirmed in the detection of thiram residue on apples, tomatoes, pears, and other fruits and vegetables.
Asunto(s)
Nanopartículas del Metal , Tiram , Tiram/análisis , Verduras/química , Frutas/química , Nanopartículas del Metal/química , Reproducibilidad de los Resultados , Plata/química , Espectrometría Raman/métodos , Celulosa/análisisRESUMEN
Plant-based hamburger patties (PHPs) with reduced fat content made using fat replacers will meet the consumption goals of individuals who consume meat alternative products for health. In this study, we developed a dual-alternative food model by analysing the applicability of bacterial cellulose paste (BCP) as a fat replacer and supplementing it in PHPs. BCPs were prepared with solid contents of (w/w; 1.0%, 1.5%, 2.0%, 2.5%, and 3.0%) and compared and analyzed with three types of conventional vegetable [coconut oil, margarine, and shortening (SH)] and animal fats (beef tallow, butter, and lard) for various characteristics (appearance, dimensional stability, hardness level, and rheological properties). According to the results, BCP with a solid content of 3.0% (w/w) had the most similar characteristics to SH. Therefore, using SH as a control fat, PHPs in which 0%, 25%, 50%, 75%, and 100% (w/w) SH were replaced by 3.0% (w/w) BCP were prepared. Analysis of the appearance, instrumental color, diameter reduction, thickness, cooking loss, and texture profile of the PHPs, confirmed that replacement of 25%-50% (w/w) SH with 3.0% (w/w) BCP in the preparation of PHP resulted in i) redder color, ii) better dimensional stability, iii) lower cooking loss, and iv) higher chewiness of the final products. The results of the sensory evaluation showed that the PHPs, with 25%-50% (w/w) SH replaced with 3.0% (w/w) BCP, exhibited no significant differences (p < 0.05) in overall preference scores compared to the full-SH sample. In conclusion, this study demonstrated the potential of BCP as a fat substitute for the production of PHPs.
Asunto(s)
Sustitutos de Grasa , Productos de la Carne , Humanos , Animales , Bovinos , Celulosa/análisis , Dieta con Restricción de Grasas , Culinaria , Productos de la Carne/análisisRESUMEN
The stem support for fresh-cut flowers exerts a profound influence on the display of their blossoms. During vase insertion, bending stems significantly affect the ornamental value, but much remains unclear about the underlying reasons. In this study, six pairs of ornamental plants were screened for the contrast of bending and straight stems. The bending stems have weakened mechanical force and biomass recalcitrance compared with the straight ones. Meanwhile, cells in the bending stems became more loosely packed, along with a decrease in cell wall thickness and cellulose levels. Furthermore, wall properties characterizations show bending stems have decreased lignocellulosic CrI and cellulose DP, and enhanced the branching ratio of hemicellulose which is trapped in the cellulose. Given the distinct cell wall factors in different species, all data are grouped in standardized to eliminate the variations among plant species. The principal composition analysis and correlation analysis of the processed dataset strongly suggest that cellulose association factors determine the stem mechanical force and recalcitrance. Based on our results, we propose a model for how branches of confined hemicellulose interacted with cellulose to modulate stem strength support for the straight or bending phenotype in cut flowers.
Asunto(s)
Celulosa , Xilanos , Celulosa/análisis , Xilanos/análisis , Plantas , Pared Celular/química , Flores , Tallos de la PlantaRESUMEN
Solid-state nuclear magnetic resonance (ssNMR) measurements of intact cell walls and cellular samples often generate spectra that are difficult to interpret due to the presence of many coexisting glycans and the structural polymorphism observed in native conditions. To overcome this analytical challenge, we present a statistical approach for analyzing carbohydrate signals using high-resolution ssNMR data indexed in a carbohydrate database. We generate simulated spectra to demonstrate the chemical shift dispersion and compare this with experimental data to facilitate the identification of important fungal and plant polysaccharides, such as chitin and glucans in fungi and cellulose, hemicellulose, and pectic polymers in plants. We also demonstrate that chemically distinct carbohydrates from different organisms may produce almost identical signals, highlighting the need for high-resolution spectra and validation of resonance assignments. Our study provides a means to differentiate the characteristic signals of major carbohydrates and allows us to summarize currently undetected polysaccharides in plants and fungi, which may inspire future investigations.
Asunto(s)
Celulosa , Polisacáridos , Polisacáridos/análisis , Polisacáridos/química , Espectroscopía de Resonancia Magnética , Celulosa/análisis , Celulosa/química , Pectinas/análisis , Pectinas/química , Imagen por Resonancia Magnética , Pared Celular/químicaRESUMEN
Pesticide residues in agri-foods have risk to human health and one solution is to develop simple and accurate methods for rapid detection. We developed a SERS sensor composed of gold nanoparticles (AuNPs) and bacterial cellulose nanocrystal (BCNC) to detect thiram in fruit juice. BCNC-SO3H was used as a stabilizer to support AuNPs via electrostatic repulsion, fabricating a BCNC-AuNPs SERS substrate with uniformly distributed AuNPs. This BCNC-AuNPs SERS substrate was applied to determine thiram residues in peach juice, apple juice, and grape juice with the limits of detection of 0.036 ppm, 0.044 ppm, and 0.044 ppm, respectively. The whole test took 12 min including sample preparation and analysis. The detection limits meet the maximum residue levels of thiram in fruit juices required by China, Europe and North America, indicating that this BCNC-based substrate could serve as a satisfactory SERS sensor for pesticide residue monitoring in the food supply chain.
Asunto(s)
Nanopartículas del Metal , Tiram , Humanos , Tiram/análisis , Jugos de Frutas y Vegetales/análisis , Celulosa/análisis , Oro/química , Nanopartículas del Metal/química , Frutas/química , Espectrometría Raman/métodosRESUMEN
BACKGROUND: Kenaf seeds are underutilized kenaf plant by-products, containing essential nutrients including dietary fiber (DF), which can be potentially utilized as food ingredients. The present study aimed to evaluate the physicochemical characteristics of kenaf seed fiber fractions extracted from kenaf seed. RESULTS: Defatted kenaf seed powder yielded four DF fractions: alkali-soluble hemicellulose (146.4 g kg-1 ), calcium-bound pectin (10.3 g kg-1 ) and acid-soluble pectin (25.4 g kg-1 ) made up the soluble fibre fraction, whereas cellulose (202.2 g kg-1 ) comprised the insoluble fraction. All fractions were evaluated for their physicochemical properties. The DF fractions contained glucose, mannose, xylose and arabinose, and a small amount of uronic acid (1.2-2.7 g kg-1 ). The isolated pectin fractions had a low degree of esterification (14-30%). All the isolated DF fractions had high average molecular weights ranging from 0.3 to 4.3 × 106 g mol-1 . X-ray diffractogram analysis revealed that the fractions consisted mainly of an amorphous structure with a relative crystallinity ranging from 31.6% to 44.1%. The Fourier-transform infrared spectroscopy spectrum of kenaf seed and its DF fractions showed typical absorption of polysaccharides, with the presence of hydroxyl, carboxyl, acetyl and methyl groups. Scanning electron microscopy analysis demonstrated that the raw material with the rigid structure resulted in soluble and insoluble DF fractions with more fragile and fibrous appearances, respectively. The soluble DF demonstrated greater flowability and compressibility than the insoluble fractions. CONCLUSION: These findings provide novel information on the DF fractions of kenaf seeds, which could be used as a potential new DF for the food industry. © 2023 Society of Chemical Industry.
Asunto(s)
Hibiscus , Hibiscus/química , Fibras de la Dieta/análisis , Pectinas/análisis , Celulosa/análisis , Semillas/químicaRESUMEN
This study assesses the viability of an accelerated solvent extraction technique employing environmentally friendly solvents to extract ellagitannins while producing cellulose-rich fibers from rambutan peel. Two sequential extraction protocols were investigated: 1) water followed by acetone/water (4:1, v:v), and 2) acetone followed by acetone/water (4:1, v:v), both performed at 50 °C. The first protocol had a higher extraction yield of 51 %, and the obtained extractives featured a higher total phenolic (531.4 ± 22.0 mg-GAE/g) and flavonoid (487.3 ± 16.9 mg-QE/g) than the second protocol (495.4 ± 32.8 mg-GAE/g and 310.6 ± 31.4 mg-QE/g, respectively). The remaining extractive-free fibers were processed by bleaching using either 2 wt% sodium hydroxide with 3 wt% hydrogen peroxide or 4-5 wt% peracetic acid. Considering bleaching efficiency, yield, and process sustainability, the single bleaching treatment with 5 wt% of peracetic acid was selected as the most promising approach to yield cellulose-rich fibers. The samples were analyzed by methanolysis to determine the amount and type of poly- and oligosaccharides and studied by 13C solid-state nuclear magnetic resonance spectroscopy and thermal gravimetric analysis. The products obtained from the peels demonstrate significant potential for use in various sectors, including food, nutraceuticals, cosmetics, and paper production.
Asunto(s)
Celulosa , Sapindaceae , Celulosa/análisis , Acetona , Taninos Hidrolizables , Sapindaceae/química , Ácido Peracético , Solventes/química , Frutas/química , Agua/análisisRESUMEN
The level of polysaccharides in the mature Lycium barbarum fruit (LBF) cell wall depends on their metabolism, trafficking, and reassembly within the cell. In this study, we examined the composition, content, and ultrastructure of the cell wall polysaccharides of LBF during maturation, and further analyzed cell wall polysaccharide remodeling using isotope tagging with relative and absolute quantification (iTRAQ)-based proteomics. The results showed that the contents of cellulose and hemicellulose tended to increase in the pre-maturation stage and decrease in the later stage, while pectin level increased before fruit maturing. The differential expression of the 54 proteins involved in the metabolic pathways for glucose, fructose, galactose, galacturonic acid and arabinose was found to be responsible for these alterations. The work provides a biological framework for the reorganization of polysaccharides in the LBF cell wall, and supports the hypothesis that pectic polysaccharide glycosyl donors come from starch, cellulose, hemicellulose and isomorphic pectin.
Asunto(s)
Lycium , Pectinas , Pectinas/análisis , Lycium/química , Frutas/química , Polisacáridos/química , Celulosa/análisis , Pared CelularRESUMEN
The effects of postharvest melatonin (MT) treatment on cuticular wax and cell wall metabolism in blueberry fruit (Vaccinium spp.) were evaluated. The results revealed that MT treatment maintained the cuticular wax rod-like structure and delayed wax degradation. The gas chromatography-mass spectrometry analysis results revealed that MT application changed the cuticular wax composition in blueberries, and 25 metabolic components were screened. The metabolic regulation of wax quality in blueberry fruit may therefore be influenced by MT. Additionally, MT slowed down pectin and cellulose degradation by reducing the activities of cell wall degrading enzymes like pectin methyl esterase polygalacturonase, ß-galactosidase, and cellulose in the later stages of storage. It also downregulated the transcriptional expression of related genes like VcPE, VcPG, VcBG6, and VcGAL1. Thus, MT prevented softening and senescence by postponing the degradation of the cell wall in postharvest blueberry fruit.