Applications of Starch Biopolymers for a Sustainable Modern Agriculture

Does the Incorporation of Biochar into Biodegradable Mulch Films Provide Agricultural Soil Benefits?

The pollution caused by plastic mulch film in agriculture has garnered significant attention. To safeguard the ecosystem from the detrimental effects of plastic pollution, it is imperative to investigate the use of biodegradable materials for manufacturing agricultural plastic film. Biochar has emerged as a feasible substance for the production of biodegradable mulch film (BDM), providing significant agricultural soil benefits. Although biochar has been widely applied in BDM manufacturing, the effect of biochar-filled plastic mulch film on soil carbon stock after its degradation has not been well documented. This study provides an overview of the current stage of biochar incorporated with BDM and summarizes its possible pathway on soil carbon stock contribution. The application of biochar-incorporated BDM can lead to substantial changes in soil microbial diversity, thereby influencing the emissions of greenhouse gases. These alterations may ultimately yield unforeseen repercussions on the carbon cycles. However, in light of the current knowledge vacuum and potential challenges, additional study is necessary to ascertain if biochar-incorporated BDM can effectively mitigate the issues of residual mulch film and microplastic contamination in agricultural land. Significant progress remains necessary before BDM may fully supplant traditional agricultural mulch film in agricultural production.

Recycling of Bovine Hair Waste Through the Design of a Compatibilizing Agent for Sustainable Thermoplastic Starch-Untreated Bovine Hair Composites

Bovine hair waste was chemically modified to obtain a coupling agent (CA) for the compatibilization of thermoplastic starch (TPS)-unmodified bovine hair waste (UH) composites. The composites processed with CA presented improved tensile strength (3.5 MPa) compared to TPS-UH composites without CA (1.25 MPa). An interaction mechanism to describe the improvement in mechanical properties and thermal stability was postulated based on Fourier-transform infrared spectroscopy (FTIR) and density functional theory (DFT). In addition, optical and electron microscopy showed that CA favored the adhesion of UH to TPS. Global results suggested the formation of a CA-UH network that interacts with the TPS matrix. Obtaining composites from waste from the tanning industry can contribute to the development of a more responsible and sustainable industry and represents an opportunity to reduce the environmental impact of one of the most important industries globally. It is worth mentioning that this research is aligned with the sustainable development goals (SDGs) proposed by the United Nations, which promotes sustainable industrialization and the promotion of innovation.

Dynamic borate ester bond reinforced hydroxyethyl cellulose/corn starch crosslinked film for simple recycling and regeneration

Endowing biodegradable plastics with easy recyclability can reduce competition with food resources and further enhance their environmental friendliness. In this work, 4-carboxyphenylboronic acid was grafted onto the side chains of hydroxyethyl cellulose and compounded with inexpensive cornstarch. Upon the introduction of tannic acid, stable and reversible borate ester bond rapidly formed, yielding composite biodegradable plastic films with outstanding mechanical properties and facile recyclability. The formation of a dynamic cross-linked network mitigates the aggregation of gelatinized starch molecules, enhancing the flexibility and durability of the crosslinked film. Testing revealed that while maintaining high tensile strength, the elongation at break of the crosslinked film increased by 952.86 %. The static water contact angle was improved from 32.74° to 78.82°, with a change of <5° within 1 min, demonstrating enhanced water resistance. Excellent antioxidant and thermal stability were also characterized, the crosslinked film can be easily dissolved by heating in water at pH = 6.5 and reshaped in water at pH = 7.2. After five times of regeneration, the tensile strength loss was as low as 5.68 %. This eco-friendly and efficient recycling process is promising during green chemistry.

Determination of insecticidal potential of selected plant extracts against fall armyworm (Spodoptera frugiperda) larvae

The fall armyworm, Spodoptera frugiperda (J.E. Smith), is a devastating pest that attacks a wide range of crops, including sugarcane, rice, and maize. The purpose of this study is to evaluate the toxicity potential of native plant extracts (Azadirachta indica, Eucalyptus globulus, Parthenium hysterophorus, Cannabis sativa, Citrullus colocynthis, Nicotiana tabacum) against S. frugiperda. Four different concentrations (50, 100, 200, and 400 ppm) of the ethanolic plant extracts was evaluated against S. frugiperda third-instar larvae to determine their median lethal concentration (LC50). After 72 h of exposure, the LC50 values of A. indica, E. globulus, P. hysterophorus, C. sativa, C. colocynthis, N. tabacum, and positive control (Spinetoram) were 186.104, 518.438, 320.027, 334.259, 252.651, 720.980 and 189.369 ppm respectively. The maximum percent mortality was caused by the highest concentration (400 ppm) of A. indica (64 ± 0.18), E. globulus (48 ± 0.22), P. hysterophorus (56 ± 0.18), C. sativa (56 ± 0.18), C. colocynthis (60 ± 0.00), and N. tabacum (40 ± 0.28), after 72 h of treatment while Spinetoram induced 100 ± 0.00 percent mortality of S. frugiperda and only 4 ± 0.18 percent mortality was recorded in a control group. Results showed that all plant extracts were found to be effective against S. frugiperda. The compounds from the two most effective ethanolic plant extracts were identified by using Gas chromatography-mass spectrometry analysis (GC-MS). The key compounds identified in neem leaf extract and kortuma fruit extract are predominantly biologically active molecules. Many of them were volatile compounds that belonged to different chemical categories, such as fatty acids, hydrocarbons, esters, terpenoids, phenolic compounds, and amines. Terpenes exhibited a wide range of different biological activities, such as serving as insecticides and antifeedant. The presence of various functional groups in the plant extract was determined by conducting a Fourier Transform Infrared Spectroscopy (FTIR). Farmers should employ these kinds of environmental friendly insecticides to lessen the impact of fall armyworm because these products are cheaper to use and better for the economy and the environment.

A comprehensive review on starch-based sustainable edible films loaded with bioactive components for food packaging

Biopolymers like starch, a renewable and widely available resource, are increasingly being used to fabricate the films for eco-friendly packaging solutions. Starch-based edible films offer significant advantages for food packaging, including biodegradability and the ability to extend shelf life. However, they also present challenges such as moisture sensitivity and limited barrier properties compared to synthetic materials. These limitations can be mitigated by incorporating bioactive components, such as antimicrobial agents or antioxidants, which enhance the film's resistance to moisture and improve its barrier properties, making it a more viable option for food packaging. This review explores the emerging field of starch-based sustainable edible films enhanced with bioactive components for food packaging applications. It delves into fabrication techniques, structural properties, and functional attributes, highlighting the potential of these innovative films to reduce environmental impact and preserve food quality. Key topics discussed include sustainability issues, processing methods, performance characteristics, and potential applications in the food industry. The review provides a comprehensive overview of current research and developments in starch-based edible films, presenting them as promising alternatives to conventional food packaging that can help reduce plastic waste and environmental impact.

The untold story of starch as a catalyst for organic reactions

Starch is one of the members of the polysaccharide family. This biopolymer has shown many potential applications in different fields such as catalytic reactions, water treatment, packaging, and food industries. In recent years, using starch as a catalyst has attracted much attention. From a catalytic point of view, starch can be used in organic chemistry reactions as a catalyst or catalyst support. Reports show that as a catalyst, simple starch can promote many heterocyclic compound reactions. On the other hand, functionalized starch is not only capable of advancing the synthesis of heterocycles but also is a good candidate catalyst for other reactions including oxidation and coupling reactions. This review tries to provide a fair survey of published organic reactions which include using starch as a catalyst or a part of the main catalyst. Therefore, the other types of starch applications are not the subject of this review.

Natural polysaccharides and proteins-based films for potential food packaging and mulch applications: A review

Conventional nondegradable packaging and mulch films, after reaching the end of their use, become a major source of waste and are primarily disposed of in landfills. Accumulation of non-degradable film residues in the soil leads to diminished soil fertility, reduced crop yield, and can potentially affect humans. Application of degradable films is still limited due to the high cost, poor mechanical, and gas barrier properties of current biobased synthetic polymers. In this respect, natural polysaccharides and proteins can offer potential solutions. Having versatile functional groups, three-dimensional network structures, biodegradability, ease of processing, and the potential for surface modifications make polysaccharides and proteins excellent candidates for quality films. Besides, their low-cost availability as industrial waste/byproducts makes them cost-effective alternatives. This review paper covers the performance properties, cost assessment, and in-depth analysis of macromolecular structures of some natural polysaccharides and proteins-based films that have great potential for packaging and mulch applications. Proper dissolution of biopolymers to improve molecular interactions and entanglement, and establishment of crosslinkages to form an ordered and cohesive polymeric structure can help to obtain films with good properties. Simple aqueous-based film formulation techniques and utilization of waste/byproducts can stimulate the adoption of affordable biobased films on a large-scale.

Synthesis and application of multifunctional lignin-modified cationic waterborne polyurethane in textiles

Waterborne polyurethanes (WPUs) often have limitations like inadequate weathering resistance and thermal stability. To overcome these shortcomings, lignin has been selected as a modifier for its abundant availability, renewability, and biocompatibility. This study synthesized a cationic WPU using isophorone diisocyanate and polyethylene glycol as raw materials. Hydrophilicity was attained through the inclusion of dihydroxyethyl dodecylamine as a chain extender, while the introduction of epoxy monomers and lignin served to modify the polyurethane. Furthermore, a dye dispersion for cotton fabric dyeing was prepared by combining the synthesized polyurethane, chitosan, and dyes. The cationic nature of the polyurethane played a crucial role in facilitating dye adhesion and uptake on the fabric surface, resulting in improved dyeing performance. The incorporation of epoxy side chains and chitosan cross-linking contributed to the excellent color fastness of the dyed fabrics. Moreover, the incorporation of lignin and chitosan endowed the fabric with antibacterial properties. Simultaneously, it provided effective UV protection, characterized by a high UV protection factor value for the fabrics. This lignin-modified WPU exhibits tremendous potential in applications such as textile coatings, adhesives, and color fixation agents. It effectively addresses the limitations of traditional WPUs and offers notable advantages, including a renewable source, cost-effectiveness, and biocompatibility.

Identification of Plastics in Mixtures and Blends through Pyrolysis-Gas Chromatography/Mass Spectrometry

In this paper, the possibility of detecting polymers in plastic mixtures and extruded blends has been investigated. Pyrolysis-gas chromatography/mass spectrometry (py-GC/MS) allows researchers to identify multicomponent mixtures and low amounts of polymers without high spatial resolution, background noise and constituents mix interfering, as with molecular spectrometry techniques normally used for this purpose, such as Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy and differential scanning calorimetry (DSC). In total, 15 solid mixtures of low-density polyethylene (LDPE), polypropylene (PP), polystyrene (PS), polyamide (PA) and polycarbonate (PC) in various combinations have been qualitatively analyzed after choosing their characteristic pyrolysis products and each polymer has been detected in every mix; thus, in extruded blends of high-density polyethylene (HDPE), PP and PS had varying weight percentages of the individual constituents ranging from 10 up to 90. Moreover, quantitative analysis of these polymers has been achieved in every blend with a trend that can be considered linear with coefficients of determination higher than 0.9, even though the limits of quantification are lower with respect to the ones reported in the literature, probably due to the extrusion process.

Exploring carbohydrate extraction from biomass using deep eutectic solvents: Factors and mechanisms

Deep eutectic solvents (DESs) are increasingly being recognized as sustainable and promising solvents because of their unique properties: low melting point, low cost, and biocompatibility. Some DESs possess high viscosity, remarkable stability, and minimal toxicity, enhancing their appeal for diverse applications. Notably, they hold promise in biomass pretreatment, a crucial step in biomass conversion, although their potential in algal biomass carbohydrates extraction remains largely unexplored. Understanding the correlation between DESs' properties and their behavior in carbohydrate extraction, alongside cellulose degradation mechanisms, remains a gap. This review provides an overview of the use of DESs in extracting carbohydrates from lignocellulosic and algal biomass, explores the factors that influence the behavior of DESs in carbohydrate extraction, and sheds light on the mechanism of cellulose degradation by DESs. Additionally, the review discusses potential future developments and applications of DESs, particularly extracting carbohydrates from algal biomass.

Comparative Genomics and Transcriptomics Analyses Reveal Divergent Plant Biomass-Degrading Strategies in Fungi

Plant biomass is one of the most abundant renewable carbon sources, which holds great potential for replacing current fossil-based production of fuels and chemicals. In nature, fungi can efficiently degrade plant polysaccharides by secreting a broad range of carbohydrate-active enzymes (CAZymes), such as cellulases, hemicellulases, and pectinases. Due to the crucial role of plant biomass-degrading (PBD) CAZymes in fungal growth and related biotechnology applications, investigation of their genomic diversity and transcriptional dynamics has attracted increasing attention. In this project, we systematically compared the genome content of PBD CAZymes in six taxonomically distant species, Aspergillus niger, Aspergillus nidulans, Penicillium subrubescens, Trichoderma reesei, Phanerochaete chrysosporium, and Dichomitus squalens, as well as their transcriptome profiles during growth on nine monosaccharides. Considerable genomic variation and remarkable transcriptomic diversity of CAZymes were identified, implying the preferred carbon source of these fungi and their different methods of transcription regulation. In addition, the specific carbon utilization ability inferred from genomics and transcriptomics was compared with fungal growth profiles on corresponding sugars, to improve our understanding of the conversion process. This study enhances our understanding of genomic and transcriptomic diversity of fungal plant polysaccharide-degrading enzymes and provides new insights into designing enzyme mixtures and metabolic engineering of fungi for related industrial applications.

Effect of Polyethylene Glycol Methyl Ether Methacrylate on the Biodegradability of Polyvinyl Alcohol/Starch Blend Films

Blend copolymers (PVA/S) were grafted with polyethylene glycol methyl methacrylate (PEGMA) with different ratios. Potassium persulfate was used as an initiator. The blend copolymer (PVA/S) was created by combining poly(vinyl alcohol) (PVA) with starch (S) in various ratios. The main idea was to study the effect of different ratios of the used raw materials on the biodegradability of plastic films. The resulting polymers (PVA/S/PEGMA) were analyzed using FTIR spectroscopy to investigate the hydrogen bond interaction between PVA, S, and PEGMA in the mixtures. TGA and SEM analyses were used to characterize the polymers (PVA/S/AA). The biodegradability and mechanical properties of the PVA/S/PEGMA blend films were evaluated. The findings revealed that the mechanical properties of the blend films are highly influenced by PEGMA. The time of degradation of the films immersed in soil and Coca-Cola increases as the contents of PVA and S and the molecular weight (MW) of PEGMA increase in the terpolymer. The M8 sample (PVA/S/PEGMA in the ratio of 3:1:2, respectively) with a MW of 950 g/mol produced the lowest elongation at break (67.5%), whereas M1 (PVA/S/PEGMA in the ratio of 1:1:1, respectively) with a MW of 300 g/mol produced the most (150%). The film's tensile strength and elongation at break were improved by grafting PEGMA onto the blending polymer (PAV-b-S). Tg and Tm increased when the PEGMA MW increased from 300 to 950. Tg (48.4 °C) and Tm (190.9 °C) were the lowest in M1 (300), while Tg (84.8 °C) and Tm (190.9 °C) were greatest in M1 (950) at 209.3 °C. The increased chain and molecular weight of PEGMA account for the increase in Tg and Tm of the copolymers.

Barley thermoplastic starch nanocomposite films reinforced with nanocellulose

Despite being one of the starch producers, barley has yet to be widely studied for thermoplastic starch applications, including nanocellulose thermoplastic composites, due to its uses in the food and beverage industries. However, only 20% of barley is used in the malting industry to produce both alcoholic and non-alcoholic beverages, and 5% is used as an ingredient in a wide variety of foods. As the fourth most important cereal in the world after wheat, corn, and rice, barley can be considered an interesting biomass source to produce biodegradable thermoplastics, stemming from its starch constitution. Therefore, this review attempts to highlight the barley starch properties and its potential utilization for nanocellulose thermoplastic starch composites. Several studies involving barley-based starch in thermoplastic production and nanocellulose reinforcement for properties enhancement are also reviewed, particularly in the attempt to provide various options to reduce and replace the uses of harmful petroleum-based plastic.

Explication of mechanism governing atmospheric degradation of 3D-printed poly(lactic acid) (PLA) with different in-fill pattern and varying in-fill density

With the popularity of 3D-printing technology, poly(lactic acid) (PLA) has become a very good option for layer by layer printing as it is easy to handle, environment friendly, has low costs and most importantly, it is highly adaptable to different materials including carbon, nylon and some other fibres. PLA is an aliphatic poly-ester that is 100% bio-based and is bio-degradable as well. It is one of the rare bio-polymers to compete with traditional polymers in terms of performance and environmental impact. However, PLA is sensitive to water and susceptible to degradation under natural conditions of ultra-violet rays (UV), humidity, fumes, etc. There are many reports on the bio-degradation and photo-degradation of PLA which deal with the accelerated weathering test. However, the accelerated weathering test instruments lack the ability to correlate the stabilities maintained by the test with the actual occurrences during natural exposure. Thus, an attempt has been made in the present work to expose the 3D-printed PLA samples to actual atmospheric conditions of Aurangabad city (M.S.) in India. The degradation of PLA after the exposure is studied and a mechanism is elucidated. Additionally, the tensile properties of the PLA samples are evaluated to correlate the extent of degradation and the material performance. It was found that though the performance of PLA deteriorates with the exposure time, the combination of in-fill pattern and volume plays an important role on the tensile properties and the extent of degradation. It is concluded herein that with natural exposure, the degradation of PLA occurs in two stages, supported by a side reaction. Thus, this study offers a new perspective towards the life of components in actual application by exposing PLA to the natural atmosphere and evaluating its strength and structure.

Encapsulating biocontrol bacteria with starch as a safe and edible biopolymer to alleviate plant diseases: A review

Healthy foods with few artificial additives are in high demand among consumers. Preserving conventional pesticides, frequently used as chemicals to control phytopathogens, is challenging. Therefore, we proposed an innovative approach to protect agricultural products in this review. Biocontrol bacteria are safe alternatives with low stability and low efficiency in the free-form formulation. The encapsulation technique for covering active compounds (e.g., antimicrobials) represents a more efficient protection technology because encapsulation causes the controlled release of bioactive materials and reduces the application doses. Of the biopolymers able to form a capsule, starch exhibits several advantages, such as its ready availability, cost-effectively, edible, colorless, and tasteless. Nevertheless, the poor mechanical properties of starch can be improved with other edible biopolymers. In addition, applying formulations incorporated with more than one antimicrobial material offers synergistic effects. This review presented the starch-based capsules used to enclose antimicrobial agents as effective tools against phytopathogens.

Comprehensive Enzymatic Conversion of Starch for the Food Industry

This study demonstrated the feasibility of comprehensive enzymatic conversion of starch for non-waste applications in food industry. Enzymatic conversion of starch gives rise to nano-sized particles that can be used for manufacturing biodegradable and edible packaging materials and glucose syrup for replacing sugar in confectionery formulations. The 96 h enzymatic hydrolysis yielded starch nanoparticles smaller than 100 nm. Films based on nano-sized starch particles have promising physicochemical properties for manufacturing biodegradable and edible packaging materials. Such properties as reduced moisture content, increased homogeneity, crystallinity, and high initial thermal stability improve the mechanical and performance characteristics of the final food packaging materials. During film formation from starch subjected to preliminary mechanical amorphization, the polymer chain is recrystallized. The C-type crystal structure of starch is converted to the B-type structure. The supernatant obtained by starch hydrolysis can be used for producing glucose syrup. The resulting glucose syrup can be used as a sugar substitute in production of confectionery products. No objective technological differences in properties of glucose syrup obtained by comprehensive conversion of starch and the commercially available glucose syrup derived from sucrose were revealed.

Environmental Properties and Applications of Biodegradable Starch-Based Nanocomposites

In recent years, the demand for environmental sustainability has caused a great interest in finding novel polymer materials from natural resources that are both biodegradable and eco-friendly. Natural biodegradable polymers can displace the usage of petroleum-based synthetic polymers due to their renewability, low toxicity, low costs, biocompatibility, and biodegradability. The development of novel starch-based bionanocomposites with improved properties has drawn specific attention recently in many applications, including food, agriculture, packaging, environmental remediation, textile, cosmetic, pharmaceutical, and biomedical fields. This paper discusses starch-based nanocomposites, mainly with nanocellulose, chitin nanoparticles, nanoclay, and carbon-based materials, and their applications in the agriculture, packaging, biomedical, and environment fields. This paper also focused on the lifecycle analysis and degradation of various starch-based nanocomposites.

Life Cycle Assessment and Life Cycle Cost of an Innovative Carbon Paper Sensor for 17α-Ethinylestradiol and Comparison with the Classical Chromatographic Method

Nowadays there is a growing concern with the environment and sustainability, which means that better methods, including pollutants analysis, with less consumption of materials, organic solvents, and energy, need to be developed. Considering the almost inexistent information about the topic, the main goal of this work was to compare the environmental impacts of two analytical methods, a traditional one based on liquid chromatography with fluorescence detection and a newly developed carbon paper sensor. The selected analyte was 17α-ethinylestradiol, which is a contaminant of emergent concern in aquatic ecosystems due to its endocrine disruptor behavior. The life cycle assessment data showed that the sensor detection presents an almost negligible environmental impact when compared with the extraction step (the same for both methods) and the liquid chromatographic determination (roughly 80 times higher than with the sensor). The sensor values for all categories of damage are below 3% of the total method impacts, i.e., 1.6, 1.9, 2.4, and 2.9% for resources, climate change, human health, and ecosystem quality. The extraction represents 98.1% of the sensor environmental impacts (and 99.6% of its life cycle costing) and 38.8% of the chromatographic method. This study evidences the need of developing and applying greener analytical (detection and extraction) strategies.