Search

Sunflower oil (SFO) and Flaxseed oil (FSO) were microencapsulated using simple and complex coacervation techniques with Opuntia (Cactaceae) mucilage (Mu) and with a combination of Mu with chitosan (Chit). The encapsulation efficiency (EE) of SFO and FSO in emulsions using Mu/Chit shells was 96.7% and 97.4%, respectively. Morphological studies indicated successful entrapment of oils in core shells with particle sizes ranging from 1396 ± 42.4 to 399.8 ± 42.3 nm. The thermogravimetric analyses demonstrated enhanced core protection with thermal stability noted for microcapsules regardless of encapsulation method. The stability of the microcapsules, during in vitro digestion was studied. The obtained results revealed that the microcapsules are intact in oral conditions and have a slow release of oil over stomach digestion and rapid release in the small intestine. The results showed that Mu and Mu/Chit coacervates can be used as effective carrier systems to encapsulate sensitive ingredients and functional oils., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This study evaluated the feasibility of using cactus mucilage (CM) to elaborate biobased composite films blended with styrene-butadiene rubber latex (SBL). The CM was extracted and precipitated with ethanol (CMET) and isopropanol (CMIS). Mucilage-based films were formulated using three levels of mucilage (4, 6, and 8 wt%). The microstructure, thickness, moisture content, density, water contact angle, water vapor permeability, film solubility, thermal stability, and toughness of mucilage films blended with SBL (SBL/CMET and SBL/CMIS) were measured. The properties of mucilage-based films varied systematically, depending on the concentration of mucilage. The addition of SBL to CM film produces compatible, hydrophobic, flexible, and stiffer films with low moisture contents and good barrier properties. The mucilage film incorporated with 6 wt% CMET and CMIS reached the highest Young's modulus of 1512 ± 21 and 1988 ± 55 MPa, respectively. The DSC of produced films reveals that the Tg of SBL/CMIS is lower than that of SBL/CMIS. The synthesized films were structurally stable at high temperatures. The biodegradability of the composite films buried in the ground shows that the produced films are 100 % biodegradable after 40 days. Thus, CM blended with SBL can benefit specific applications, especially food packaging., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The aim of this work is to investigate the adsorption of an anionic dye, the Murexide (MX) present in aqueous solution, on activated carbon, derived from prickly pear seed cake biomass after bio-oil extraction. The obtained adsorbent used was characterized by Bohem titration, pH of point of zero charge (pHPZC), FTIR spectroscopy, Brunauer–Emmett–Teller surface area (SBET), and scanning electron microscopy (SEM). The different experimental parameters of the adsorption process, such as temperature, contact time, initial dye concentration, and adsorbent dose, were studied. For the optimization of the process, the effects of these parameters were investigated using the full factorial experimental design methodology. Design Expert 11.1.2.0 Trial software was used for generating the statistical experimental design and analysing the observed data. Langmuir and Freundlich's adsorption models were employed to provide a description of the equilibrium isotherm. The adsorption process was found to obey Langmuir, which indicates that the Murexide had formed a monolayer onto activated carbon. Furthermore, according to the regression coefficients, it was observed that the kinetic adsorption data can fit better by the pseudo-second-order model compared to the first-order Lagergren's model. The thermodynamic studies indicated that the adsorption of Murexide occurs in a spontaneous and exothermic process. The regeneration process of the exhausted adsorbent was studied to assess the economic and operational feasibility. According to the obtained findings, it is proposed that the activated carbon prepared from prickly pear seed cake retains a high potential for Murexide removal and is suitable for repetitive usage. [ABSTRACT FROM AUTHOR]

Activated carbon obtained from Opuntia ficus indica by sodium hydroxide activation was employed for the adsorption of p-nitrophenol from water. The activated carbons obtained were characterized by Fourier transforms infrared spectroscopy, sorption of nitrogen, scanning electron microscopy, and Boehm titration. Effects of pH, contact time, amount of adsorbent, and temperature on the adsorption of p-nitrophenol were studied. Adsorption isotherms were analyzed using Freundlich, Langmuir, Temkin, and Dubinin-Radushkevich models, and the thermodynamic parameters have been determined. The adsorption of p-nitrophenol was spontaneous, exothermic, and propitious at 15 °C and adopted the pseudo-second order model, and the most credible isotherm was Langmuir's one. The activated carbon used in this work has good p-nitrophenol adsorption characteristics, and the study of the desorption and reuse of this carbon shows that it retains a removal rate greater than 94% after five cycles of adsorption-desorption. [ABSTRACT FROM AUTHOR]

This study was aimed at investigating the micro-formulation of capsules using natural biopolymers, such as cactus mucilage (CM), carboxymethyl cellulose sodium salt (CMCNa) and chitosan (Chi) as the wall material, for the transport and supply of sunflower oil. CM samples were extracted from Opuntia ficus indica (OFI) by precipitation at different supernatant pH values (2, 4 and 12). The extracted natural polysaccharide and the resulting microcapsules were characterized by different experimental techniques. Fourier transform infrared spectroscopy analysis of the CM showed the presence of uronic acid units and sugars. Scanning electron microscopy revealed that most particles were adhered together, causing the formation of compact, linked agglomerates, which resulted in different microstructures with irregular shapes. All oil-core microcapsules were characterized, and the results showed that the different shell materials could be used to microencapsulate sunflower oil. Among them, the microcapsule crosslinked with CM and Chi was the most suitable, with the highest encapsulation efficiency (95 %). This coacervation led to the narrowest size distribution of the capsules, with diameters ranging from 1 to 5 µm. Optical microscopy confirmed the deposition of coacervate droplets around oil drops and clearly showed that the formation of coacervated particles and their deposition onto oil droplets were successive events. [ABSTRACT FROM AUTHOR]

Highlights • A green process was used to manually extract fibrous networks from the cactus plant. • Fibrous layers have a natural net-like structure with a low bulk density. • Fibrous networks have good thermal stability and suitable mechanical properties. Abstract The present study focuses on the extraction and characterization of natural cellulosic tissues from the cactus Opuntia ficus-indica. A major goal is the establishment of a "green" process for fibrous networks extraction that allows for biomass valorization using sustainable plant fibers. This process shall contribute to the eco-friendly concept. Numerous separated fibrous layers (tissues) with intricate structures were obtained from different parts of the plant. Bulk density and thicknesses of the fibrous layers were determined including evaluation of fiber swelling (water uptake test) and detailed arrangement of the fibrous layers according to thickness was given. A good layer distribution and different values of bulk density were obtained for the studied tissues. The macrostructure (topology and geometric parameters) and microstructure (internal and anatomical structures) of fibrous networks were studied using both bright-field microscopy and scanning electron microscopy. A high diversity of fibers having a complex hierarchical structure was observed. The study of the fibrous-networks crystallinity and the thermostability indicate that water-immersion processing ameliorated the thermal stability in some temperature regions. The fibrous networks mechanical studies were examined, and the results showed a good response strength, especially for uniaxial tensile layers, which has led to the highest strength and elastic modulus. [ABSTRACT FROM AUTHOR]