جستجوی مقالات مرتبط با کلیدواژه « lignin » در نشریات گروه « پزشکی »

The goal of tissue engineering is to repair and regenerate diseased and damaged tissues and organs with functional and biocompatible materials that mimic native and original tissues which leads to maintaining and improvement of tissue function. Lignin and cellulose are the most abundant polymers in nature and have many applications in industry. Moreover, recently the physicochemical behaviors of lignin and cellulose, including biocompatibility, biodegradability, and mechanical properties, have been used in diverse biological applications ranging from drug delivery to tissue engineering. To assess these aims, this review gives an overview and comprehensive knowledge and highlights the origin and applications of lignin and cellulose-derived scaffolds in different tissue engineering and other biological applications. Finally, the challenges for future development using lignin and cellulose are also included. Plant-based tissue engineering is a promising technology for progressing areas in biomedicine, regenerative medicine, and nanomedicine, with much research focused on the development of newer material scaffolds with individual specific features to make functional and biocompatible tissues and organs for medical applications.

Estrogens are of the most dangerous micro/nanopollutants that have shown severe influences on the ecosystems and micro-organisms. There is an ever-increasing demand to reliably detect and practically remove these estrogens from effluents. In a recently proposed method, estrogens can be detected and removed from effluents using a sampler (lignin). In this study it has been shown that ionic liquids are a potential choice to separate the adsorbed estrogens from the surface of “dirty” lignin so that the sampler could be reused. More than 300 ionic liquids were screened for removing estrogens from the lignin surface by employing a quantum chemistry method, COnductor-like Screening MOdel (COSMO), to determine the interaction quality between the ionic liquid and eight estrogens of interest. The results revealed that there are at least 24 solvents that can remove adsorbed estrogens from the surface of lignin. This prediction completes the cycle of reusing lignin as an efficient polymeric sampler to remove estrogens from effluents and provokes experimental justifications.

Biopolymer scaffolds have received great interest in academic and industrial environment because of their supreme characteristics like biological, mechanical, chemical, and cost saving in the biomedical science. There are various attempts for incorporation of biopolymers with cheap natural micro- or nanoparticles like lignin (Lig), alginate, and gums to prepare new materials with enhanced properties.
In this work, the electrospinning (ELS) technique as a promising cost-effective method for producing polymeric scaffold fibers was used, which mimics extracellular matrix structure for soft tissue engineering applications. Nanocomposites of Lig and polycaprolactone (PCL) scaffold produced with ELS technique. Nanocomposite containings (0, 5, 10, and 15 wt.%) of Lig were prepared with addition of Lig powder into the PCL solution while stirring at the room temperature. The bioactivity, swelling properties, morphological and mechanical tests were conducted for all the samples to investigate the nanocomposite scaffold features.
The results showed that scaffold with 10 wt.% Lig have appropriate porosity, biodegradation, minimum fiber diameter, optimum pore size as well as enhanced tensile strength, and young modulus compared with pure PCL. Degradation test performed through immersion of samples in the phosphate-buffer saline showed that degradation of PCL nanocomposites could accelerate up to 10% due to the addition of Lig.
Electrospun PCLLig scaffold enhanced the biological response of the cells with the mechanical signals. The prepared nanocomposite scaffold can choose for potential candidate in the biomedical science

Biopolymer scaffolds have received great interest in academic and industrial environment because of their supreme characteristics like biological, mechanical, chemical, and cost saving in the biomedical science. There are various attempts for incorporation of biopolymers with cheap natural micro- or nanoparticles like lignin (Lig), alginate, and gums to prepare new materials with enhanced properties.
In this work, the electrospinning (ELS) technique as a promising cost-effective method for producing polymeric scaffold fibers was used, which mimics extracellular matrix structure for soft tissue engineering applications. Nanocomposites of Lig and polycaprolactone (PCL) scaffold produced with ELS technique. Nanocomposite containings (0, 5, 10, and 15 wt.%) of Lig were prepared with addition of Lig powder into the PCL solution while stirring at the room temperature. The bioactivity, swelling properties, morphological and mechanical tests were conducted for all the samples to investigate the nanocomposite scaffold features.
The results showed that scaffold with 10 wt. % Lig have appropriate porosity, biodegradation, minimum fiber diameter, optimum pore size as well as enhanced tensile strength, and young modulus compared with pure PCL. Degradation test performed through immersion of samples in the phosphate-buffer saline showed that degradation of PCL nanocomposites could accelerate up to 10% due to the addition of Lig.
Electrospun PCL-Lig scaffold enhanced the biological response of the cells with the mechanical signals. The prepared nanocomposite scaffold can choose for potential candidate in the biomedical science.

Residues of medicinal plants after extraction and weeds are suitable candidates for bioethanol production. Significant barriers exist to make the conversion of lignocellulosic feedstock to biofuel cost effective and environmentally friendly; one of which is the lignin polymer. Brassicaceae family is one of the potential targets for biofuel production. The structural characteristics of lignin from Hirschfeldia incana, Sisymbrium altissimum and Cardaria draba were studied in comparison to that of Brassica napus.

Lignin deposition was observed by phloroglucinol and Mäule staining. The total lignin content was determined by Klason method. Maximum UV absorbance and FT-IR spectra were compared. Ratio of syringyl to guaiacyl lignin (S/G ratio) as a metric of lignin digestibility was determined by DFRC followed by GC-MS analysis. 1H-NMR spectra of the total lignin was compared with other spectroscopic methods.

Staining of thestem cross sections of C. draba showed higher G units in contrast to the higher S units in S. altissimum which was in agreement with 1H-NMR analysis. Total lignin content for H. incana, C. draba and S. altissimum was 27.10%, 23.8% and 24.5%, respectively. The specific maximum UV absorbance appeared between 230-260 nm. FT-IR analysis confirmed the presence of more aromatic structures in the seed maturation stage than the flowering stage. S/G ratio was 0.26, 0.10 and 0.22 for H. incana, C. draba and S. altissimum, respectively. 

Except Cardaria draba with the predominance of G subunits in lignin polymer, Hirschfeldia incana and Sisymbrium altissimum are suitable candidates for bioethanol production.

Aims of the Study: The aim of this study was to determine the amount of lignin degradation and biodegradation of organic matter and change of biomass under compost and vermicomposting of sewage sludge. Sawdust was added to sewage sludge at 1:3 weight bases to Carbon to Nitrogen ratio of 25:1 for composting or vermicomposting. Lignin and volatile solids were determined at different periods, of 0, 10, 30, 40 and 60 days of composting or vermicomposting period to determine the biodegradation of lignocellulose to lignin. Results were expressed as mean of two replicates and the comparisons among means were made using the least significant difference test calculated (p <0.05). After 60 days of experiment period, the initial lignin increased from 3.46% to 4.48% for compost and 3.46% to 5.27% for vermicompost. Biodegradation of lignocellulose was very slow in compost and vermicompost processes. Vermicomposting is a much faster process than compost to convert lignocellulose to lignin (p <0.05). The organic matter losses in sewage sludge composting and vermicomposting are due to the degradation of the lignin fractions. By increasing compost age, the amount of volatile solids will decrease.