Closing the Loop with Keratin-Rich Fibrous Materials

One of the agro-industry’s side streams that is widely met is the-keratin rich fibrous material that is becoming a waste product without valorization. Its management as a waste is costly, as the incineration of this type of waste constitutes high environmental concern. Considering these facts, the keratin-rich waste can be considered as a treasure for the producers interested in the valorization of such slowly-biodegradable by-products. As keratin is a protein that needs harsh conditions for its degradation, and that in most of the cases its constitutive amino acids are destroyed, we review new extraction methods that are eco-friendly and cost-effective. The chemical and enzymatic extractions of keratin are compared and the optimization of the extraction conditions at the lab scale is considered. In this study, there are also considered the potential applications of the extracted keratin as well as the reuse of the by-products obtained during the extraction processes.

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Latest Insights on Novel Deep Eutectic Solvents (DES) for Sustainable Extraction of Phenolic Compounds from Natural Sources

Molecules ◽

10.3390/molecules26165037 ◽

2021 ◽

Vol 26 (16) ◽

pp. 5037

Author(s):

Julio Serna-Vázquez ◽

Mohd Zamidi Ahmad ◽

Grzegorz Boczkaj ◽

Roberto Castro-Muñoz

Keyword(s):

Phenolic Compounds ◽

Molecular Mechanisms ◽

Deep Eutectic Solvents ◽

Natural Sources ◽

Extraction Solvent ◽

Potential Applications ◽

Extraction Processes ◽

Phenolic Extraction ◽

Sustainable Extraction ◽

By Products

Phenolic compounds have long been of great importance in the pharmaceutical, food, and cosmetic industries. Unfortunately, conventional extraction procedures have a high cost and are time consuming, and the solvents used can represent a safety risk for operators, consumers, and the environment. Deep eutectic solvents (DESs) are green alternatives for extraction processes, given their low or non-toxicity, biodegradability, and reusability. This review discusses the latest research (in the last two years) employing DESs for phenolic extraction, solvent components, extraction yields, extraction method characteristics, and reviewing the phenolic sources (natural products, by-products, wastes, etc.). This work also analyzes and discusses the most relevant DES-based studies for phenolic extraction from natural sources, their extraction strategies using DESs, their molecular mechanisms, and potential applications.

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Fish Collagen: Extraction, Characterization, and Applications for Biomaterials Engineering

Polymers ◽

10.3390/polym12102230 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2230 ◽

Cited By ~ 1

Author(s):

Hafez Jafari ◽

Alberto Lista ◽

Manuela Mafosso Siekapen ◽

Pejman Ghaffari-Bohlouli ◽

Lei Nie ◽

...

Keyword(s):

Biomedical Applications ◽

Deep Eutectic Solvent ◽

Cost Effective ◽

Extraction Methods ◽

Low Molecular Weight ◽

Collagen Structure ◽

Liquid Ratio ◽

Fish Collagen ◽

Extraction Parameters ◽

By Products

The utilization of marine-based collagen is growing fast due to its unique properties in comparison with mammalian-based collagen such as no risk of transmitting diseases, a lack of religious constraints, a cost-effective process, low molecular weight, biocompatibility, and its easy absorption by the human body. This article presents an overview of the recent studies from 2014 to 2020 conducted on collagen extraction from marine-based materials, in particular fish by-products. The fish collagen structure, extraction methods, characterization, and biomedical applications are presented. More specifically, acetic acid and deep eutectic solvent (DES) extraction methods for marine collagen isolation are described and compared. In addition, the effect of the extraction parameters (temperature, acid concentration, extraction time, solid-to-liquid ratio) on the yield of collagen is investigated. Moreover, biomaterials engineering and therapeutic applications of marine collagen have been summarized.

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Identification and Recovery of Valuable Bioactive Compounds from Potato Peels: A Comprehensive Review

Antioxidants ◽

10.3390/antiox10101630 ◽

2021 ◽

Vol 10 (10) ◽

pp. 1630

Author(s):

Beatriz Rodríguez-Martínez ◽

Beatriz Gullón ◽

Remedios Yáñez

Keyword(s):

Biological Activities ◽

Chemical Compounds ◽

Extraction Methods ◽

Added Value ◽

Antioxidant Compounds ◽

Potato Peel ◽

Industrial Processing ◽

Potential Applications ◽

Potato Peels ◽

By Products

Nowadays, the potato is one of the most cultivated and consumed food crops in the world and, in recent years, its production has experienced a sharp increase. Its industrial processing generates several by-products that are wasted and cause economic and environmental problems. Among them, potato peel stands out, representing up to 10% of the total potato residues obtained in the processing. On the other hand, these wastes, in addition to presenting antioxidant compounds, are rich in interesting chemical compounds of great value in a biorefinery model. This review summarizes the main compounds present in potato skins as well as the most used and innovative extraction methods employed for their isolation, with special emphasis on the fractions with biological activities. In addition, a sustainable biorefinery proposal focused on obtaining high added-value products with potential applications in the pharmaceutical, food, nutraceutical, or cosmetic industries is included.

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Rapid Detection and Quantification of Patulin and Citrinin Contamination in Fruits

Molecules ◽

10.3390/molecules26154545 ◽

2021 ◽

Vol 26 (15) ◽

pp. 4545

Author(s):

Sudharsan Sadhasivam ◽

Omer Barda ◽

Varda Zakin ◽

Ram Reifen ◽

Edward Sionov

Keyword(s):

High Performance ◽

Cost Effective ◽

Hplc Method ◽

Pear Fruit ◽

Cost Effective Method ◽

Fruit Samples ◽

Pome Fruits ◽

Reliable Methods ◽

By Products ◽

Detection And Quantification

Patulin (PAT) and citrinin (CTN) are the most common mycotoxins produced by Penicillium and Aspergillus species and are often associated with fruits and fruit by-products. Hence, simple and reliable methods for monitoring these toxins in foodstuffs are required for regular quality assessment. In this study, we aimed to establish a cost-effective method for detection and quantification of PAT and CTN in pome fruits, such as apples and pears, using high-performance liquid chromatography (HPLC) coupled with spectroscopic detectors without the need for any clean-up steps. The method showed good performance in the analysis of these mycotoxins in apple and pear fruit samples with recovery ranges of 55–97% for PAT and 84–101% for CTN, respectively. The limits of detection (LOD) of PAT and CTN in fruits were 0.006 µg/g and 0.001 µg/g, while their limits of quantification (LOQ) were 0.018 µg/g and 0.003 µg/g, respectively. The present findings indicate that the newly developed HPLC method provides rapid and accurate detection of PAT and CTN in fruits.

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Black Phosphorus-Molybdenum Disulfide Hetero-Junctions Formed with Ink-Jet Printing for Potential Solar Cell Applications with Indium-Tin-Oxide

Crystals ◽

10.3390/cryst11050560 ◽

2021 ◽

Vol 11 (5) ◽

pp. 560

Author(s):

Ravindra Ketan Mehta ◽

Anupama Bhat Kaul

Keyword(s):

Electrical Properties ◽

Molybdenum Disulfide ◽

Tin Oxide ◽

Indium Tin Oxide ◽

Cost Effective ◽

Contact Materials ◽

Ito Glass ◽

The Future ◽

Potential Applications ◽

Jet Printing

In this work, we implemented liquid exfoliation to inkjet-print two-dimensional (2D) black phosphorous (BP) and molybdenum disulfide (MoS2) p–n heterojunctions on a standard indium tin oxide (ITO) glass substrate in a vertical architecture. We also compared the optical and electrical properties of the inkjet-printed BP layer with that of the MoS2 and the electrical properties of the mechanically exfoliated MoS2 with that of the inkjet-printed MoS2. We found significant differences in the optical characteristics of the inkjet-printed BP and MoS2 layers attributed to the differences in their underlying crystal structure. The newly demonstrated liquid exfoliated and inkjet-printed BP–MoS2 2D p–n junction was also compared with previous reports where mechanically exfoliated BP–MoS2 2D p–n junction were used. The electronic transport properties of mechanically exfoliated MoS2 membranes are typically better compared to inkjet-printed structures but inkjet printing offers a cost-effective and quicker way to fabricate heterostructures easily. In the future, the performance of inkjet-printed structures can be further improved by employing suitable contact materials, amongst other factors such as modifying the solvent chemistries. The architecture reported in this work has potential applications towards building solar cells with solution processed 2D materials in the future.

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Sporulation in solventogenic and acetogenic clostridia

Applied Microbiology and Biotechnology ◽

10.1007/s00253-021-11289-9 ◽

2021 ◽

Author(s):

Mamou Diallo ◽

Servé W. M. Kengen ◽

Ana M. López-Contreras

Keyword(s):

Current Knowledge ◽

Carbon Sources ◽

Cost Effective ◽

Biotechnological Production ◽

Key Points ◽

Wide Range ◽

Potential Applications ◽

A Cell ◽

Sporulation Initiation ◽

Solventogenic Clostridia

AbstractThe Clostridium genus harbors compelling organisms for biotechnological production processes; while acetogenic clostridia can fix C1-compounds to produce acetate and ethanol, solventogenic clostridia can utilize a wide range of carbon sources to produce commercially valuable carboxylic acids, alcohols, and ketones by fermentation. Despite their potential, the conversion by these bacteria of carbohydrates or C1 compounds to alcohols is not cost-effective enough to result in economically viable processes. Engineering solventogenic clostridia by impairing sporulation is one of the investigated approaches to improve solvent productivity. Sporulation is a cell differentiation process triggered in bacteria in response to exposure to environmental stressors. The generated spores are metabolically inactive but resistant to harsh conditions (UV, chemicals, heat, oxygen). In Firmicutes, sporulation has been mainly studied in bacilli and pathogenic clostridia, and our knowledge of sporulation in solvent-producing or acetogenic clostridia is limited. Still, sporulation is an integral part of the cellular physiology of clostridia; thus, understanding the regulation of sporulation and its connection to solvent production may give clues to improve the performance of solventogenic clostridia. This review aims to provide an overview of the triggers, characteristics, and regulatory mechanism of sporulation in solventogenic clostridia. Those are further compared to the current knowledge on sporulation in the industrially relevant acetogenic clostridia. Finally, the potential applications of spores for process improvement are discussed.Key Points• The regulatory network governing sporulation initiation varies in solventogenic clostridia.• Media composition and cell density are the main triggers of sporulation.• Spores can be used to improve the fermentation process.

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Physico-mechanical properties of plywood bonded with ecological adhesives from Acacia mollissima tannins and lignosulfonates

The European Physical Journal Applied Physics ◽

10.1051/epjap/2017170067 ◽

2017 ◽

Vol 78 (3) ◽

pp. 34813 ◽

Cited By ~ 6

Author(s):

Naima Rhazi ◽

Mina Oumam ◽

Abdessadek Sesbou ◽

Hassan Hannache ◽

Fatima Charrier-El Bouhtoury

Keyword(s):

Mechanical Properties ◽

Mechanical Performance ◽

Phenol Formaldehyde ◽

Waste Product ◽

Formaldehyde Emission ◽

Extraction Methods ◽

Press Temperature ◽

Pulp Industry ◽

Pressing Time ◽

Chemical Conditions

The objective of this research was to develop ecological adhesives for bonding plywood panels using lignosulfonates, a common waste product of the wood pulp industry, and natural tannin extracted from Moroccan bark of Acacia mollissima using different process. Natural tannin and lignin were used in wood adhesives formulation to substitute resins based on phenol and formaldehyde. To achieve this, the lignosulfonates were glyoxalated to enhance their reactivity and the used tannins obtained by three different extraction methods were compared with commercial mimosa tannin. The proportion of Acacia mollissima tannins and lignosulfonates, the pressing time, the pressing temperature, and the pressure used were studied to improve mechanical properties, and bonding quality of plywood panel. The properties of plywood panels produced with these adhesives were tested in accordance with normative tests. Thus, the tensile strength, and the shear strength were measured. The results showed that the performance of the plywood panels made using biobased tannin adhesives was influenced by physical conditions such as pressure, press temperature as well as by chemical conditions, such as the tannin-lignin ratio. It exhibited excellent mechanical properties comparable to commercially available phenol-formaldehyde plywood adhesives. This study showed that biobased adhesives formulations presented good and higher mechanical performance and no formaldehyde emission.

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Synthesis and Conductivity Studies of Poly(Methyl Methacrylate) (PMMA) by Co-Polymerization and Blending with Polyaniline (PANi)

Polymers ◽

10.3390/polym13121939 ◽

2021 ◽

Vol 13 (12) ◽

pp. 1939

Author(s):

Helyati Abu Hassan Shaari ◽

Muhammad Mahyiddin Ramli ◽

Mohd Nazim Mohtar ◽

Norizah Abdul Rahman ◽

Azizan Ahmad

Keyword(s):

Methyl Methacrylate ◽

Mechanical Stability ◽

Chemical Properties ◽

Cost Effective ◽

Poly Methyl Methacrylate ◽

Conducting Materials ◽

Potential Applications ◽

Polymerization Condition ◽

Physical And Chemical ◽

And Chemical Properties

Poly(methyl methacrylate) (PMMA) is a lightweight insulating polymer that possesses good mechanical stability. On the other hand, polyaniline (PANi) is one of the most favorable conducting materials to be used, as it is easily synthesized, cost-effective, and has good conductivity. However, most organic solvents have restricted potential applications due to poor mechanical properties and dispersibility. Compared to PANi, PMMA has more outstanding physical and chemical properties, such as good dimensional stability and better molecular interactions between the monomers. To date, many research studies have focused on incorporating PANi into PMMA. In this review, the properties and suitability of PANi as a conducting material are briefly reviewed. The major parts of this paper reviewed different approaches to incorporating PANi into PMMA, as well as evaluating the modifications to improve its conductivity. Finally, the polymerization condition to prepare PMMA/PANi copolymer to improve its conductivity is also discussed.

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Transformation of Glass Fiber Waste into Mesoporous Zeolite-Like Nanomaterials with Efficient Adsorption of Methylene Blue

Sustainability ◽

10.3390/su13116207 ◽

2021 ◽

Vol 13 (11) ◽

pp. 6207

Author(s):

Cheng-Kuo Tsai ◽

Jao-Jia Horng

Keyword(s):

Methylene Blue ◽

Glass Fiber ◽

Environmental Concern ◽

Cost Effective ◽

Environmentally Benign ◽

Mesoporous Zeolite ◽

Trace Metal Ions ◽

Langmuir Adsorption ◽

Ceramic Ring ◽

Cost Effective Method

Recycling and reusing glass fiber waste (GFW) has become an environmental concern, as the means of disposal are becoming limited as GFW production increases. Therefore, this study developed a novel, cost-effective method to turn GFW into a mesoporous zeolite-like nanomaterial (MZN) that could serve as an environmentally benign adsorbent and efficient remover of methylene blue (MB) from solutions. Using the Taguchi optimizing approach to hydrothermal alkaline activation, we produced analcime with interconnected nanopores of about 11.7 nm. This MZN had a surface area of 166 m2 g−1 and was negatively charged with functional groups that could adsorb MB ranging from pH 2 to 10 and all with excellent capacity at pH 6.0 of the maximum Langmuir adsorption capacity of 132 mg g−1. Moreover, the MZN adsorbed MB exothermically, and the reaction is reversible according to its thermodynamic parameters. In sum, this study indicated that MZN recycled from glass fiber waste is a novel, environmentally friendly means to adsorb cation methylene blue (MB), thus opening a gateway to the design and fabrication of ceramic-zeolite and tourmaline-ceramic balls and ceramic ring-filter media products. In addition, it has environmental applications such as removing cation dyes and trace metal ions from aqueous solutions and recycling water.

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Structure, Mechanics and Failure of Stochastic Fibrous Networks: Part I—Microscale Considerations

Journal of Engineering Materials and Technology ◽

10.1115/1.1288769 ◽

2000 ◽

Vol 122 (4) ◽

pp. 450-459 ◽

Cited By ~ 46

Author(s):

C. W. Wang ◽

L. Berhan ◽

A. M. Sastry

Keyword(s):

Load Transfer ◽

Nonlinear Behavior ◽

Polymeric Composite ◽

Cost Effective ◽

Failure Criteria ◽

Zone Model ◽

Fibrous Materials ◽

Linear Solution ◽

Model Complex ◽

Computationally Intensive

Applications for porous fibrous materials range from electrochemical substrates to web reinforcement in polymeric composite materials. The details of local load transfer are studied in a class of cost-effective, stochastic fibrous networks used in battery applications, which form the substrate for a composite electrode. The connectivity of these materials is quantitatively related to modulus and strength, and detailed results of different simulations approaches in approximating material construction are discussed. In Part I, we discuss microscale assumptions, including beam type, nodal connections and equivalence of models to more physically realistic models. Simulation of large networks is computationally intensive, and show low-strain, nonlinear behavior even when comprised of elastic elements when failure criteria (here, strength-of-materials) are applied to produce sequential rupture of beams and nodes. Strategies for effective simulation of these materials requires detailed analysis of the simplest assumptions which can be made at the microscale which produce acceptably realistic response. We show that simple Euler-Bernoulli beam elements can be used to effectively model such materials, even when segment lengths in a network are very small. Moreover, connections comprised of simple torsion springs produce realistic behavior, and can mimic more realistic junctures by adaptation of the linear solution to a compliant zone model. In Part II of this work, we demonstrate the effect of model selection on full network behavior, and also discuss issues of connectivity at the scale of the porous material rather than element-by-element. This work points toward use of simple constructions to model complex behavior, and may ultimately provide insight into modeling of a large class of porous materials. [S0094-4289(00)01704-7]

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