Optimization of Cellulosic Fiber Extraction from Parsley Stalks and Utilization as Filler in Composite Biobased Films

Development of tissue-engineered vascular grafts from decellularized parsley stems

Cardiovascular diseases are mostly associated with narrowing or blockage of blood vessels, and it is the most common cause of death worldwide. The use of vascular grafts is a promising approach to bypass or replace the blocked vessels for long-term treatment. Although autologous arteries or veins are the most preferred tissue sources for vascular bypass, the limited presence and poor quality of autologous vessels necessitate seeking alternative biomaterials. Recently, synthetic grafts have gained attention as an alternative to autologous grafts. However, the high failure rate of synthetic grafts has been reported primarily due to thrombosis, atherosclerosis, intimal hyperplasia, or infection. Thrombosis, the main reason for failure upon implantation, is associated with damage or absence of endothelial cell lining in the vascular graft's luminal surface. To overcome this, tissue-engineered vascular grafts (TEVGs) have come into prominence. Alongside the well-established scaffold manufacturing techniques, decellularized plant-based constructs have recently gained significant importance and are an emerging field in tissue engineering and regenerative medicine. Accordingly, in this study, we demonstrated the fabrication of tubular scaffolds from decellularized parsley stems and recellularized them with human endothelial cells to be used as a potential TEVG. Our results suggested that the native plant DNA was successfully removed, and soft tubular biomaterials were successfully manufactured via the chemical decellularization of the parsley stems. The decellularized parsley stems showed suitable mechanical and biological properties to be used as a TEVG material, and they provided a suitable environment for the culture of human endothelial cells to attach and create a pseudo endothelium prior to implantation. This study is the first one to demonstrate the potential of the parsley stems to be used as a potential TEVG biomaterial.

A Review on Barrier Properties of Cellulose/Clay Nanocomposite Polymers for Packaging Applications

Packaging materials are used to protect consumer goods, such as food, drinks, cosmetics, healthcare items, and more, from harmful gases and physical and chemical damage during storage, distribution, and handling. Synthetic plastics are commonly used because they exhibit sufficient characteristics for packaging requirements, but their end lives result in environmental pollution, the depletion of landfill space, rising sea pollution, and more. These exist because of their poor biodegradability, limited recyclability, etc. There has been an increasing demand for replacing these polymers with bio-based biodegradable materials for a sustainable environment. Cellulosic nanomaterials have been proposed as a potential substitute in the preparation of packaging films. Nevertheless, their application is limited due to their poor properties, such as their barrier, thermal, and mechanical properties, to name a few. The barrier properties of materials play a pivotal role in extending and determining the shelf lives of packaged foods. Nanofillers have been used to enhance the barrier properties. This article reviews the literature on the barrier properties of cellulose/clay nanocomposite polymers. Cellulose extraction stages such as pretreatment, bleaching, and nanoparticle isolation are outlined, followed by cellulose modification methods. Finally, a brief discussion on nanofillers is provided, followed by an extensive literature review on the barrier properties of cellulose/clay nanocomposite polymers. Although similar reviews have been presented, the use of modification processes applied to cellulose, clay, and final nanocomposites to enhance the barrier properties has not been reviewed. Therefore, this article focuses on this scope.

Green solid-liquid extraction of cactus (Opuntia ficus-indica) cladode dietary fibers. I- optimization, pilot-scale production, and characterization

In this research work, an optimization of an environment friendly extraction method of cactus (Opuntia ficus indica) cladode dietary fibers was conducted. For this purpose, a central composite experimental design with two factors (temperature and time) and five levels was established. The basic objective of this optimization was to maximize fiber yield using hot water as an extraction eco-solvent. The optimum extraction time (330 min) and temperature (100 °C) were determined with a constant medium agitation rate. Additionally, this study also aimed at establishing the validation of the statistical model to carry out the extrapolation of the extraction process at the pilot scale. The fibers extracted at the pilot scale showed yields (45.2 ± 0.01%) in agreement with those obtained through the optimization and validation lab-scale steps (44.97 ± 0.02). Fourier Transform Infrared (FTIR) spectroscopy, X-ray Diffraction (XRD) and Scanning electron microscopy (SEM) analysis were conducted to investigate the structure and microstructure of pilot scale-produced fibers. FTIR spectrum and XRD pattern were typical to lignocellulosic fibers results. Sharp and thin peaks characteristic of cellulose were detected. Pure and crystallized phases were recorded with a 45% crystallinity index. SEM analysis presented elongated and organized cells with a uniform structure comparable to cellulosic fibers microstructure.