Polymers

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16 pages, 17180 KiB

Open AccessArticle

Complex Impedance and Modulus Analysis on Porous and Non-Porous Scaffold Composites Due to Effect of Hydroxyapatite/Starch Proportion

by Chong You Beh, Ee Meng Cheng, Xiao Jian Tan, Nashrul Fazli Mohd Nasir, Mohd Shukry Abdul Majid, Mohd Ridzuan Mohd Jamir, Shing Fhan Khor, Kim Yee Lee and Che Wan Sharifah Robiah Mohamad

Polymers 2023, 15(2), 320; https://doi.org/10.3390/polym15020320 - 8 Jan 2023

Cited by 1 | Viewed by 1884

Abstract

This study aims to investigate the electric responses (complex modulus and complex impedance analysis) of hydroxyapatite/starch bone scaffold as a function of hydroxyapatite/starch proportion and the microstructural features. Hence, the non-porous and porous hydroxyapatite/starch composites were fabricated with various hydroxyapatite/starch proportions (70/30, 60/40, [...] Read more.

This study aims to investigate the electric responses (complex modulus and complex impedance analysis) of hydroxyapatite/starch bone scaffold as a function of hydroxyapatite/starch proportion and the microstructural features. Hence, the non-porous and porous hydroxyapatite/starch composites were fabricated with various hydroxyapatite/starch proportions (70/30, 60/40, 50/50, 40/60, 30/70, 20/80, and 10/90 wt/wt%). Microstructural analysis of the porous hydroxyapatite/starch composites was carried out by using scanning electron microscopy. It shows that the formation of hierarchical porous microstructures with high porosity is more significant at a high starch proportion. The complex modulus and complex impedance analysis were conducted to investigate the electrical conduction mechanism of the hydroxyapatite/starch composites via dielectric spectroscopy within a frequency range from 5 MHz to 12 GHz. The electrical responses of the hydroxyapatite/starch composites are highly dependent on the frequency, material proportion, and microstructures. High starch proportion and highly porous hierarchical microstructures enhance the electrical responses of the hydroxyapatite/starch composite. The material proportion and microstructure features of the hydroxyapatite/starch composites can be indirectly reflected by the simulated electrical parameters of the equivalent electrical circuit models. Full article

(This article belongs to the Special Issue Biopolymers: Recent Progress and New Perspectives II)

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23 pages, 4054 KiB

Open AccessArticle

Use of Dynamic Shear Rheology to Understand Soy Protein Dispersion Properties

by Charles R. Frihart and Matthew Gargulak

Polymers 2022, 14(24), 5490; https://doi.org/10.3390/polym14245490 - 15 Dec 2022

Cited by 5 | Viewed by 1956

Abstract

Soy flour dispersions are used as adhesives for bonding interior wood laminates, but the high viscosity of these dispersions requires low solids in the adhesive formulations; the greater water content causes excessive steam pressure during hot press manufacturing. This limits the utility of [...] Read more.

Soy flour dispersions are used as adhesives for bonding interior wood laminates, but the high viscosity of these dispersions requires low solids in the adhesive formulations; the greater water content causes excessive steam pressure during hot press manufacturing. This limits the utility of soy adhesives in replacing urea–formaldehyde adhesives; thus, understanding the cause of high soy viscosities is important. Lack of literature on aqueous soy flour dispersion rheology led to our dynamic rheology studies of these dispersions to understand high viscosity and the effect of various additives. Even at low soy solids, the elastic nature outweighs the viscous properties at low shear, although increasing the shear results in shear-thinning behavior after the yield point. At even higher shear, beyond the flow point where the storage and loss moduli cross, some of the dispersions show an additional shear thinning transition. The comparison of the rheological properties of aqueous dispersions of the soy flour and protein isolate, and another natural protein, ovalbumin from egg whites, led to a better understanding of different types of rheological behaviors. The experimental observations of two observed shear thinning events for soy are consistent with the model of dispersed particles, forming clusters that then form large scale flocculants. Full article

(This article belongs to the Special Issue Biopolymers: Recent Progress and New Perspectives II)

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10 pages, 3253 KiB

Open AccessArticle

In Silico Study: Combination of α-Mangostin and Chitosan Conjugated with Trastuzumab against Human Epidermal Growth Factor Receptor 2

by Sandra Megantara, Nasrul Wathoni, Ahmed Fouad Abdelwahab Mohammed, Cecep Suhandi, Maryam H. Ishmatullah and Melisa F. F. D. Putri

Polymers 2022, 14(13), 2747; https://doi.org/10.3390/polym14132747 - 5 Jul 2022

Cited by 11 | Viewed by 2152

Abstract

Breast cancer is a type of cancer with the highest prevalence worldwide. Almost 10–30% of breast cancer cases are diagnosed as positive for HER2 (human epidermal growth factor receptor 2). The currently available treatment methods still exhibit many shortcomings such as a high [...] Read more.

Breast cancer is a type of cancer with the highest prevalence worldwide. Almost 10–30% of breast cancer cases are diagnosed as positive for HER2 (human epidermal growth factor receptor 2). The currently available treatment methods still exhibit many shortcomings such as a high incidence of side effects and treatment failure due to resistance. This in silico study aims to simulate α-mangostin and chitosan combination conjugated to trastuzumab formulation against HER2 as an effort to improve breast cancer patient therapy. This molecular docking simulation was done through using PatchDock Server. The materials used including the two-dimensional structure of α-mangostin, chitosan, and sodium tripolyphosphate from the PubChem database; trastuzumab FASTA sequence from the DrugBank database; and HER2 structure obtained from a crystal complex with PDB ID: 1N8Z. The results indicated that the particle of α-mangostin and chitosan combinations interacted mostly with the crystallizable fragment (Fc region) of trastuzumab in the conjugation process. The conjugation of trastuzumab to the particle of a combination of α-mangostin and chitosan resulted in the greatest increase in the binding score of the smallest-sized particles (50 Å) with an increase in the score of 3828 and also gave the most similar mode of interaction with trastuzumab. However, the conjugation of trastuzumab eliminated the similarity of the mode of interaction and increased the value of atomic contact energy. Thus, a cominbation of α-mangostin and chitosan conjugated to a trastuzumab formulation was predicted can increase the effectiveness of breast cancer therapy at a relatively small particle size but with the consequence of decreasing atomic contact energy. Full article

(This article belongs to the Special Issue Biopolymers: Recent Progress and New Perspectives II)

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18 pages, 2130 KiB

Open AccessArticle

Modulation of Chitosan-TPP Nanoparticle Properties for Plasmid DNA Vaccines Delivery

by Renato Nunes, Ana Sofia Serra, Aiva Simaite and Ângela Sousa

Polymers 2022, 14(7), 1443; https://doi.org/10.3390/polym14071443 - 1 Apr 2022

Cited by 11 | Viewed by 4167

Abstract

Nucleic acid vaccines have become a revolutionary technology to give a fast, safe, cost-effective and efficient response against viral infections, such as SARS-CoV-2 or Human papillomavirus (HPV). However, to ensure their effectiveness, the development of adequate methods to protect, carry, and deliver nucleic [...] Read more.

Nucleic acid vaccines have become a revolutionary technology to give a fast, safe, cost-effective and efficient response against viral infections, such as SARS-CoV-2 or Human papillomavirus (HPV). However, to ensure their effectiveness, the development of adequate methods to protect, carry, and deliver nucleic acids is fundamental. In this work, nanoparticles (NPs) of chitosan (CS)-tripolyphosphate (TPP)-plasmid DNA (pDNA) were thoroughly modulated and characterized, by measuring the charge and size through dynamic light scattering (DLS) and morphology by scanning electron microscopy (SEM). Stability, cytotoxicity and cellular uptake of NPs were also evaluated. Finally, the effect of polyplexes on the expression of HPV E7 antigen in human fibroblast and RAW cells was investigated through polymerase chain reaction (PCR) and real-time PCR. The results showed NPs with a spherical/oval shape, narrow size distribution <180 nm and positive zeta potentials (>20 mV) and good stability after one month of storage at 4 °C in formulation buffer or when incubated in culture medium and trypsin. In vitro studies of NPs cytotoxicity revealed that the elimination of formulation buffers led to an improvement in the rate of cell viability. The E7 antigen transcription was also increased for NPs obtained with high pDNA concentration (60 μg/mL). The analyzed CS-TPP-pDNA polyplexes can offer a promising vehicle for nucleic acid vaccines, not only in the prevention or treatment of viral infections, but also to fight emergent and future pathogens. Full article

(This article belongs to the Special Issue Biopolymers: Recent Progress and New Perspectives II)

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18 pages, 4816 KiB

Open AccessArticle

The Influence of Circadian Rhythm on Cancer Cells Targeting and Transfection Efficiency of a Polycation-Drug/Gene Delivery Vector

by Tânia Albuquerque, Ana R. Neves, Telma Quintela and Diana Costa

Polymers 2022, 14(4), 681; https://doi.org/10.3390/polym14040681 - 10 Feb 2022

Cited by 3 | Viewed by 2829

Abstract

The conception of novel anticancer delivery systems and the combination of chronobiology with nanotechnology may provide a powerful tool to optimize cancer therapy. In this work, polyethylenimine (PEI) has been used to complex p53 encoded plasmid DNA (pDNA), and the anticancer drug methotrexate [...] Read more.

The conception of novel anticancer delivery systems and the combination of chronobiology with nanotechnology may provide a powerful tool to optimize cancer therapy. In this work, polyethylenimine (PEI) has been used to complex p53 encoded plasmid DNA (pDNA), and the anticancer drug methotrexate (MTX) has also been loaded into the vectors. To investigate the influence of circadian clock on drug/gene delivery efficiency, HeLa, C33A and fibroblast cells have been transfected with developed PEI/pDNA/MTX delivery vectors at six different time points. Phenomena as the cellular uptake/internalization, drug/gene delivery and p53 protein production have been evaluated. The cell-associated MTX fluorescence have been monitored, and p53 protein levels quantified. In HeLa and C33A cancer cells, significant levels of MTX were found for T8 and T12. For these time points, a high amount of p53 protein was quantified. Confocal microscopy images showed successful HeLa cell’s uptake of PEI/pDNA/MTX particles, at T8. In comparison, poor levels of MTX and p53 protein were found in fibroblasts; nevertheless, results indicated rhythmicity. Data demonstrate the influence of circadian rhythm on both cancer-cells targeting ability and transfection performance of PEI/pDNA/MTX carriers and seemed to provide the optimum time for drug/gene delivery. This report adds a great contribution to the field of cancer chronobiology, highlighting the relationship between circadian rhythm and nanodelivery systems, and charting the path for further research on a, yet, poorly explored but promising topic. Full article

(This article belongs to the Special Issue Biopolymers: Recent Progress and New Perspectives II)

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11 pages, 2564 KiB

Open AccessArticle

Evidence from Thermal Aging Indicating That the Synergistic Effect of Glyoxal and Sodium Sulfite Improved the Thermal Stability of Conformational Modified Xanthan Gum

by Shuai Yuan, Jiayuan Liang, Yanmin Zhang, Hongyu Han, Tianyi Jiang, Yang Liu, Yonggang Zhang, Wei Wang and Xueqian Dong

Polymers 2022, 14(2), 243; https://doi.org/10.3390/polym14020243 - 7 Jan 2022

Cited by 4 | Viewed by 2389

Abstract

Xanthan gum is prone to thermal oxidative degradation, which limits its applications. However, conformational changes in xanthan gum and appropriate stabilizers may improve its thermal stability. Therefore, in this study, we aimed to establish a strategy to maintain the viscosity of xanthan gum [...] Read more.

Xanthan gum is prone to thermal oxidative degradation, which limits its applications. However, conformational changes in xanthan gum and appropriate stabilizers may improve its thermal stability. Therefore, in this study, we aimed to establish a strategy to maintain the viscosity of xanthan gum during long-term storage at high temperatures. We modified the original strain used for xanthan gum production by genetic engineering and added stabilizers during the production process. The structure and thermal stability of the resulting xanthan gum samples were then determined. Pyruvyl deficiency, combined with the addition of sodium sulfite and glyoxal during the production process, was found to significantly improve the maintenance of viscosity. The apparent viscosity of the new xanthan gum solution remained above 100 mPa·s after being stored at 90 °C for 48 days. Fourier-transform infrared spectra and scanning electron microscopy images showed that pyruvate-free xanthan gum with added stabilizers had more extensive cross-linking than natural xanthan gum. In conclusion, these findings may contribute to the use of xanthan gum in applications that require high temperatures for a long period of time. Full article

(This article belongs to the Special Issue Biopolymers: Recent Progress and New Perspectives II)

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14 pages, 2307 KiB

Open AccessArticle

Development of a New Formulation Based on In Situ Photopolymerized Polymer for the Treatment of Spinal Cord Injury

by Gabrielle B. Novais, Stefane dos Santos, Robertta J. R. Santana, Rose N. P. Filho, John L. S. Cunha, Bruno S. Lima, Adriano A. S. Araújo, Patricia Severino, Ricardo L. C. Albuquerque Júnior, Juliana C. Cardoso, Eliana B. Souto and Margarete Z. Gomes

Polymers 2021, 13(24), 4274; https://doi.org/10.3390/polym13244274 - 7 Dec 2021

Cited by 9 | Viewed by 3006

Abstract

Spinal Cord Injury (SCI) promotes a cascade of inflammatory events that are responsible for neuronal death and glial scar formation at the site of the injury, hindering tissue neuroregeneration. Among the main approaches for the treatment of SCI, the use of biomaterials, especially [...] Read more.

Spinal Cord Injury (SCI) promotes a cascade of inflammatory events that are responsible for neuronal death and glial scar formation at the site of the injury, hindering tissue neuroregeneration. Among the main approaches for the treatment of SCI, the use of biomaterials, especially gelatin methacryloyl (GelMA), has been proposed because it is biocompatible, has excellent mechanical properties, favoring cell adhesion and proliferation. In addition, it can act as a carrier of anti-inflammatory drugs, preventing the formation of glial scars. The present work presents the development and in situ application of a light-curing formulation based on GelMA containing a natural extract rich in anti-inflammatory, antioxidant and neuroprotective substances (hydroalcoholic extract of red propolis—HERP) in an experimental model of SCI in rats. The formulations were prepared and characterized by time of UV exposition, FTIR, swelling and degradation. The hydrogels containing 1 mg/mL of HERP were obtained by the exposure to UV radiation of 2 μL of the formulation for 60 s. The locomotor evaluation of the animals was performed by the scale (BBB) and demonstrated that after 3 and 7 days of the injury, the GelMA-HERP group (BBB = 5 and 7) presented greater recovery compared to the GelMA group (BBB = 4 and 5). Regarding the inflammatory process, using histomorphological techniques, there was an inflammation reduction in the groups treated with GelMA and GelMA-HERP, with decreases of cavitation in the injury site. Therefore, it is possible to conclude that the use of GelMA and GelMA-HERP hydrogel formulations is a promising strategy for the treatment of SCI when applied in situ, as soon as possible after the injury, improving the clinical and inflammatory conditions of the treated animals. Full article

(This article belongs to the Special Issue Biopolymers: Recent Progress and New Perspectives II)

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17 pages, 5444 KiB

Open AccessArticle

Effect of the Hemin Molecular Complexes on the Structure and Properties of the Composite Electrospun Materials Based on Poly(3-hydroxybutyrate)

by Polina Tyubaeva, Ivetta Varyan, Anton Lobanov, Anatoly Olkhov and Anatoly Popov

Polymers 2021, 13(22), 4024; https://doi.org/10.3390/polym13224024 - 21 Nov 2021

Cited by 8 | Viewed by 2641

Abstract

The creation of innovative fibrous materials based on biodegradable semicrystalline polymers and modifying additives is an urgent scientific problem. In particular, the development of biomedical materials based on molecular complexes and biopolymers with controlled properties is of great interest. The paper suggests an [...] Read more.

The creation of innovative fibrous materials based on biodegradable semicrystalline polymers and modifying additives is an urgent scientific problem. In particular, the development of biomedical materials based on molecular complexes and biopolymers with controlled properties is of great interest. The paper suggests an approach to modifying the structure and properties of the composite materials based on poly(3-hydroxybutyrate) (PHB) obtained by the electrospinning method using molecular complexes of hemin. The introduction of 1–5 wt. % of hemin has a significant effect on the supramolecular structure, morphology and properties of PHB-based fibers. Changes in the supramolecular structure intensified with the increasing hemin concentration. On the one hand, a decrease in the fraction of the crystalline phase by 8–10% was observed. At the same time, there is a decrease in the density of the amorphous phase by 15–70%. Moreover, the addition of hemin leads to an improvement in the strength characteristics of the material: the elongation at break increased by 1.5 times, and in the tensile strength, it increased by 3 times. The antimicrobial activity of the hemin-containing composite materials against Escherichia coli and Staphylococcus aureus was confirmed. The obtained materials are proposed to be used in the creation of composite systems for regenerative medicine. Full article

(This article belongs to the Special Issue Biopolymers: Recent Progress and New Perspectives II)

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18 pages, 3673 KiB

Open AccessArticle

Zinc Plus Biopolymer Coating Slows Nitrogen Release, Decreases Ammonia Volatilization from Urea and Improves Sunflower Productivity

by Maqsood Sadiq, Usama Mazhar, Ghulam Abbas Shah, Zeshan Hassan, Zahid Iqbal, Imran Mahmood, Fahad Masoud Wattoo, Muhammad Bilal Khan Niazi, Atiku Bran, Kamusiime Arthur, Nadeem Ali and Muhammad Imtiaz Rashid

Polymers 2021, 13(18), 3170; https://doi.org/10.3390/polym13183170 - 18 Sep 2021

Cited by 9 | Viewed by 2922

Abstract

Currently, the global agriculture productivity is heavily relied on the use of chemical fertilizers. However, the low nutrient utilization efficiency (NUE) is the main obstacle for attaining higher crop productivity and reducing nutrients losses from these fertilizers to the environment. Coating fertilizer with [...] Read more.

Currently, the global agriculture productivity is heavily relied on the use of chemical fertilizers. However, the low nutrient utilization efficiency (NUE) is the main obstacle for attaining higher crop productivity and reducing nutrients losses from these fertilizers to the environment. Coating fertilizer with micronutrients and biopolymer can offer an opportunity to overcome these fertilizers associated problems. Here, we coated urea with zinc sulphate (ZnS) and ZnS plus molasses (ZnSM) to control its N release, decrease the ammonia (NH₃) volatilization and improve N utilization efficiency by sunflower. Morphological analysis confirmed a uniform coating layer formation of both formulations on urea granules. A slow release of N from ZnS and ZnSM was observed in water. After soil application, ZnSM decreased the NH₃ emission by 38% compared to uncoated urea. Most of the soil parameters did not differ between ZnS and uncoated urea treatment. Microbial biomass N and Zn in ZnSM were 125 and 107% higher than uncoated urea, respectively. Soil mineral N in ZnSM was 21% higher than uncoated urea. Such controlled nutrient availability in the soil resulted in higher sunflower grain yield (53%), N (80%) and Zn (126%) uptakes from ZnSM than uncoated fertilizer. Hence, coating biopolymer with Zn on urea did not only increase the sunflower yield and N utilization efficiency but also meet the micronutrient Zn demand of sunflower. Therefore, coating urea with Zn plus biopolymer is recommended to fertilizer production companies for improving NUE, crop yield and reducing urea N losses to the environment in addition to fulfil crop micronutrient demand. Full article

(This article belongs to the Special Issue Biopolymers: Recent Progress and New Perspectives II)

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19 pages, 4517 KiB

Open AccessArticle

Synthesis and Characterization of β-Cyclodextrin-Essential Oil Inclusion Complexes for Tick Repellent Development

by Jennifer Hogenbom, Alysson Jones, Haozhe Vincent Wang, Laura Jane Pickett and Nicoletta Faraone

Polymers 2021, 13(11), 1892; https://doi.org/10.3390/polym13111892 - 7 Jun 2021

Cited by 20 | Viewed by 4988

Abstract

Essential oils (EOs) are used in several pest management applications. Due to their volatility, EOs may experience bioactivity reduction, thus requiring protection to extend their properties. In the present study, we investigated the inclusion complex formation (IC) of β-cyclodextrin (β-CD) with selected EOs [...] Read more.

Essential oils (EOs) are used in several pest management applications. Due to their volatility, EOs may experience bioactivity reduction, thus requiring protection to extend their properties. In the present study, we investigated the inclusion complex formation (IC) of β-cyclodextrin (β-CD) with selected EOs with known tick repellent activity using two co-precipitation methods. ICs were characterized by evaluating EO mass concentration and inclusion efficiency (% IE) and other instrumental methods. Co-precipitation method 2 yielded the highest EO mass concentration (88 ± 6 μg/mg β-CD) for the 1:1 molar ratio geranium Egyptian EO IC. The EO volatile release over time from the ICs was investigated by headspace SPME/GC-MS analysis. ICs were also tested in tick repellency bioassays. ICs reported significant tick repellent activity, with lemongrass IC performing best overall. Method 1 showed the best combination of high mass concentration EO, controlled volatile release, and tick repellency with lemongrass EO. The results demonstrated that β-CD had selectively encapsulated different EOs. Moreover, the formation of ICs may improve EO tick repellent properties protecting the active ingredients and providing a better, long-lasting repellent action. These findings will allow the development of more effective naturally derived repellent products to protect individuals from tick bites and prevent tick-borne illnesses. Full article

(This article belongs to the Special Issue Biopolymers: Recent Progress and New Perspectives II)

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16 pages, 1785 KiB

Open AccessArticle

Computational Study on Temperature Driven Structure–Function Relationship of Polysaccharide Producing Bacterial Glycosyl Transferase Enzyme

by Patricio González-Faune, Ignacio Sánchez-Arévalo, Shrabana Sarkar, Krishnendu Majhi, Rajib Bandopadhyay, Gustavo Cabrera-Barjas, Aleydis Gómez and Aparna Banerjee

Polymers 2021, 13(11), 1771; https://doi.org/10.3390/polym13111771 - 28 May 2021

Cited by 10 | Viewed by 3565

Abstract

Glycosyltransferase (GTs) is a wide class of enzymes that transfer sugar moiety, playing a key role in the synthesis of bacterial exopolysaccharide (EPS) biopolymer. In recent years, increased demand for bacterial EPSs has been observed in pharmaceutical, food, and other industries. The application [...] Read more.

Glycosyltransferase (GTs) is a wide class of enzymes that transfer sugar moiety, playing a key role in the synthesis of bacterial exopolysaccharide (EPS) biopolymer. In recent years, increased demand for bacterial EPSs has been observed in pharmaceutical, food, and other industries. The application of the EPSs largely depends upon their thermal stability, as any industrial application is mainly reliant on slow thermal degradation. Keeping this in context, EPS producing GT enzymes from three different bacterial sources based on growth temperature (mesophile, thermophile, and hyperthermophile) are considered for in silico analysis of the structural–functional relationship. From the present study, it was observed that the structural integrity of GT increases significantly from mesophile to thermophile to hyperthermophile. In contrast, the structural plasticity runs in an opposite direction towards mesophile. This interesting temperature-dependent structural property has directed the GT–UDP-glucose interactions in a way that thermophile has finally demonstrated better binding affinity (−5.57 to −10.70) with an increased number of hydrogen bonds (355) and stabilizing amino acids (Phe, Ala, Glu, Tyr, and Ser). The results from this study may direct utilization of thermophile-origin GT as best for industrial-level bacterial polysaccharide production. Full article

(This article belongs to the Special Issue Biopolymers: Recent Progress and New Perspectives II)

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Review

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25 pages, 2281 KiB

Open AccessReview

Selected Biopolymers’ Processing and Their Applications: A Review

by María Flórez, Patricia Cazón and Manuel Vázquez

Polymers 2023, 15(3), 641; https://doi.org/10.3390/polym15030641 - 26 Jan 2023

Cited by 27 | Viewed by 5366

Abstract

Petroleum-based polymers are used in a multitude of products in the commercial world, but their high degree of contamination and non-biodegradability make them unattractive. The development and use of polymers derived from nature offer a solution to achieve an environmentally friendly and green [...] Read more.

Petroleum-based polymers are used in a multitude of products in the commercial world, but their high degree of contamination and non-biodegradability make them unattractive. The development and use of polymers derived from nature offer a solution to achieve an environmentally friendly and green alternative and reduce waste derived from plastics. This review focuses on showing an overview of the most widespread production methods for the main biopolymers. The parameters affecting the development of the technique, the most suitable biopolymers, and the main applications are included. The most studied biopolymers are those derived from polysaccharides and proteins. These biopolymers are subjected to production methods that improve their properties and modify their chemical structure. Process factors such as temperature, humidity, solvents used, or processing time must be considered. Among the most studied production techniques are solvent casting, coating, electrospinning, 3D printing, compression molding, and graft copolymerization. After undergoing these production techniques, biopolymers are applied in many fields such as biomedicine, pharmaceuticals, food packaging, scaffold engineering, and others. Full article

(This article belongs to the Special Issue Biopolymers: Recent Progress and New Perspectives II)

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30 pages, 2975 KiB

Open AccessReview

Conversion of Lignocellulose for Bioethanol Production, Applied in Bio-Polyethylene Terephthalate

by Damayanti Damayanti, Didik Supriyadi, Devita Amelia, Desi Riana Saputri, Yuniar Luthfia Listya Devi, Wika Atro Auriyani and Ho Shing Wu

Polymers 2021, 13(17), 2886; https://doi.org/10.3390/polym13172886 - 27 Aug 2021

Cited by 28 | Viewed by 7169

Abstract

The increasing demand for petroleum-based polyethylene terephthalate (PET) grows population impacts daily. A greener and more sustainable raw material, lignocellulose, is a promising replacement of petroleum-based raw materials to convert into bio-PET. This paper reviews the recent development of lignocellulose conversion into bio-PET [...] Read more.

The increasing demand for petroleum-based polyethylene terephthalate (PET) grows population impacts daily. A greener and more sustainable raw material, lignocellulose, is a promising replacement of petroleum-based raw materials to convert into bio-PET. This paper reviews the recent development of lignocellulose conversion into bio-PET through bioethanol reaction pathways. This review addresses lignocellulose properties, bioethanol production processes, separation processes of bioethanol, and the production of bio-terephthalic acid and bio-polyethylene terephthalate. The article also discusses the current industries that manufacture alcohol-based raw materials for bio-PET or bio-PET products. In the future, the production of bio-PET from biomass will increase due to the scarcity of petroleum-based raw materials. Full article

(This article belongs to the Special Issue Biopolymers: Recent Progress and New Perspectives II)

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15 pages, 912 KiB

Open AccessReview

Persea Americana Agro-Industrial Waste Biorefinery for Sustainable High-Value-Added Products

by Anthony Mora-Sandí, Abigail Ramírez-González, Luis Castillo-Henríquez, Mary Lopretti-Correa and José Roberto Vega-Baudrit

Polymers 2021, 13(11), 1727; https://doi.org/10.3390/polym13111727 - 25 May 2021

Cited by 33 | Viewed by 6888

Abstract

Significant problems have arisen in recent years, such as global warming and hunger. These complications are related to the depletion and exploitation of natural resources, as well as environmental pollution. In this context, bioprocesses and biorefinery can be used to manage agro-industrial wastes [...] Read more.

Significant problems have arisen in recent years, such as global warming and hunger. These complications are related to the depletion and exploitation of natural resources, as well as environmental pollution. In this context, bioprocesses and biorefinery can be used to manage agro-industrial wastes for obtaining high-value-added products. A large number of by-products are composed of lignin and cellulose, having the potential to be exploited sustainably for chemical and biological conversion. The biorefinery of agro-industrial wastes has applications in many fields, such as pharmaceuticals, medicine, material engineering, and environmental remediation. A comprehensive approach has been developed toward the agro-industrial management of avocado (Persea americana) biomass waste, which can be transformed into high-value-added products to mitigate global warming, save non-renewable energy, and contribute to health and science. Therefore, this work presents a comprehensive review on avocado fruit waste biorefinery and its possible applications as biofuel, as drugs, as bioplastics, in the environmental field, and in emerging nanotechnological opportunities for economic and scientific growth. Full article

(This article belongs to the Special Issue Biopolymers: Recent Progress and New Perspectives II)

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