Electron Beam Irradiation Pretreatment Research Articles

Effect of electron beam irradiation pretreatment and different fatty acid types on the formation, structural characteristics and functional properties of starch-lipid complexes

The effects of different electron beam irradiation doses (2, 4, 8 KGy) and various types of fatty acids (lauric acid, stearic acid, and oleic acid) on the formation, structure, physicochemical properties, and digestibility of starch-lipid complex were investigated. The complexing index of the complexes was higher than 85 %, indicating that the three fatty acids could easily form complexes with starch. With the increase of electron beam irradiation dose, the complexing index increased first and then decreased. The highest complexing index was lauric acid (97.12 %), stearic acid (96.80 %), and oleic acid (97.51 %) at 2 KGy radiation dose, respectively. Moreover, the microstructure, crystal structure, thermal stability, rheological properties, and starch solubility were analyzed. In vitro digestibility tests showed that adding fatty acids could reduce the content of hydrolyzed starch, among which the resistant starch content of the starch-oleic acid complex was the highest (54.26 %). The lower dose of electron beam irradiation could decrease the digestibility of starch and increase the content of resistant starch.

Techno-economic analysis of electron beam irradiation pretreatment of corn straw for anaerobic digestion

The complexity of anaerobic digestion process and the risks of investing in new technologies are the main obstacles to improving anaerobic digestion technology. There is still a gap between research results and commercial applications. This study investigated the techno-economic feasibility and bottlenecks of introducing electron beam irradiation pretreatment technology into the commercial-scale anaerobic digestion plant. Model construction, parameter initialization and economic analysis were performed in SuperPro Designer software. The parameters used in the model were derived from experimental results, software built-in model and recent literature. The results show that the gross margin, return on investment, payback time, internal rate of return, and net present value of the system with electron beam irradiation pretreatment are 4.4 %, 9.8 %, 10.1 years, 8.0 % and $0.6 million, respectively. The corresponding values of the system without electron beam irradiation pretreatment are 9.9 %, 11.1 %, 8.9 years, 9.7 % and $1.5 million, respectively. The main factor affecting gross profit is tipping fee of liquid anaerobic digestion effluent, followed by plant size of anaerobic digestion, degradation efficiency of corn straw, and compost price. This study has guiding significance for the application of electron beam irradiation pretreatment technology in the production of renewable energy from lignocellulosic biomass.

Insights into the enhanced mechanism of electron beam pretreatment on application performance for poly (butylene adipate-co-terephthalate)/acetylated cellulose composite plastics

In this work, we developed a strategy to construct poly (butylene adipate-co-terephthalate) (PBAT) composite plastics with excellent mechanical properties, superior thermal stability and enhanced biodegradability by combining acetylated celluloses (ECs) mediated by electron beam irradiation (EBI), which works as a toughening agent. With findings, the EBI pretreatment assisted with acetylation was applied to develop ECs materials with a higher degree of acetylation than acetylation alone. The pretreated ECs with increased hydrophobicity tended to decrease the chance of self-aggregation and enhanced the interfacial compatibility and adhesion with PBAT in PBAT/ECs composite plastics. Thus, PBAT/ECs composite plastics exhibited a smoother and more uniform surface structure during preparation and offered higher tensile strength, water vapor transmission rate, water absorption rate, thermal stability and degradation rate, and lower elongation at a break during application. On top of that, the PBAT/ECs composite plastics were characterized by a series of methods containing Fourier transform infrared spectroscopy and X-ray diffraction, indicating that these properties are mainly caused by the acetylation of hydroxyl groups from cellulose and carboxyl groups of PBAT. The work is expected to expand the application scope of PBAT and cellulose and provide an attainable solution for a biodegradable substitute for traditional plastics.

Electron beam pre-irradiation enhances substitution degree, and physicochemical and functional properties of carboxymethyl peanut shell nanocellulose

Nanocellulose (NC) has attracted close attention in research and industry fields because of its excellent properties and plentiful hydroxyl group accessible for surface modification. In this study, the cellulose isolated from peanut shells was used to prepare carboxymethylated nanocellulose (CMNC) under different reaction conditions, and Electron beam irradiation (EBI) pretreatment with different doses (40, 80 and 120 KGy) was previously used before modification to improve the reaction accessibility of nanocellulose. The substitution degree (DS), structural, physicochemical and functional properties of carboxymethyl CMNC with EBI pretreatment were investigated. The results showed that the peanut shell nano cellulose was a typical rod-like structure with a diameter of 5–40 nm and a length of 50–300 nm, the aspect ratio distribution was about 6.37, and EBI pretreatment significantly improved the modification effect of CMNC. The DS of the unirradiated sample was 0.38 and 0.48, and the DS increased to 0.66 and 0.69 at the irradiation dose of 120 kGy, which increased by 74% and 44%, respectively. The carboxymethyl modification changed the morphology of nanocellulose from the original short rod-like to spherical particles, and the effect was more evident with the increase of irradiation dose. FTIR showed that the nanocellulose successfully introduced carboxyl groups, the crystalline structure of nanocellulose was changed by carboxymethyl reaction. The Zeta potential result showed that the dispersion stability of CMNC suspension was improved. These results provide a helpful basis for further investigations on the modification in nanocellulose induced by EBI, verifying the effectiveness and feasibility of using EBI to modify nanofibers. They are expected to guide the transformation of nanocellulose and its most possible applications in the future to improve its performance in different applications.

Electron beam irradiation pretreatment for efficient extraction of pectin from spaghetti squash peel: Structural, functional, and biological properties

The effects of electron beam irradiation (EBI) pretreatment on the extraction, structure, functional, and biological properties of pectin from spaghetti squash peel were investigated. The spaghetti squash peel powder was pretreated by EBI with different doses (0, 25, 50, 75, 100, 125, and 150 kGy), and then pectin samples were successfully prepared in combination with acid extraction. At low doses (25 and 50 kGy), EBI had little effect on the basic structure of pectin, which was manifested by the high molecular weight, degree of esterification and viscosity of the extracted pectin. Additionally, pectin obtained at middle doses (75 and 100 kGy) exhibited high homogalacturonan (HG) domain and excellent thermal stability, while pectin extracted at high doses (125 and 150 kGy) manifested high rhamnogalacturonan Ⅰ (RG-Ⅰ) content, low molecular weight, and superior antioxidant and probiotic properties in vitro. Reasonable modulation of irradiation doses could obtain the desired pectins with different structures and properties. These findings provides valuable insights regarding the role of EBI pretreatment in the extraction and quality improvement of pectin and further promotes the appropriate application of EBI in the food industry.

Effects of electron beam irradiation pretreatment on the substitution degree, multiscale structure and physicochemical properties of OSA-esterified rice starch

In order to investigate the effect of electron beam irradiation (EBI) pretreatment on the structure and physicochemical properties of octenyl succinic acid (OSA) esterified rice starch. In this study, rice starch was pretreated with EBI (2, 4, 6 KGy) followed by OSA esterification (3%, 6%). EBI pretreatment significantly increased the OSA-esterified starch's degree of substitution (0.0173–0.0305). However, the relative crystallinity of OSA-esterified starch decreased after EBI pretreatment. And the peak viscosity, trough viscosity and final viscosity of starch decreased significantly with the increase in irradiation dose. Moreover, EBI pretreatment significantly reduced gelatinization temperature and B3 chain content of OSA-esterified starch, and significantly increased transparency, solubility, swelling power and A chain content. In addition, OSA-esterified starch's RDS content decreased and RS + SDS content increased after EBI pretreatment. The PCA results suggest that EBI may affect the physicochemical properties of starch by acting on its structure. The results showed that EBI pretreatment improved the physicochemical and functional properties of OSA-esterified starch, which is expected to broaden its application scope.

Irradiation-Assisted Hydrothermal Conversion of Water Hyacinth Leaves to Fluorescence Carbon Dots with High Quantum Yield

Electron beam irradiation (EBI) (100−400 kGy) was utilised to pretreat water hyacinth (WH). Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), fourier transform infrared (FTIR), UV-vis absorption and fluorescence spectroscopy were used to examine the effects of EBI and hydrothermal temperatures on the physical, chemical and optical characteristics of carbon dots (CDs). The combination of 400 kGy-pretreatment and 250°C-hydrothermal treatment as the optimal condition for CDs synthesis provided the highest quantum yield (QY) of 14.5% and the product yield of 7.5%. Using dynamic light scattering (DLS), the CDs showed an average size of around 180 nm, and the zeta potential analysis revealed the overall negative charge on the CDs’ surface. In comparison, the CDs synthesised via hydrothermal conversion at 250°C without EBI showed a QY of only 4.0% and a product yield of 3.8%, significantly lower than the condition with 400 kGy-pretreatment. The improved optical characteristics of the CDs could result from the high nitrogen contents of WH biomass, oxygen-rich surfaces from EBI pretreatment at 400 kGy and the aromatic skeleton of the CDs.

The role and mechanism of electron beam irradiation in glutaric anhydride esterified proso millet starch: Multi-scale structure and physicochemical properties

To investigate the effect of electron beam irradiation (EBI) pretreatment on the multiscale structure and physicochemical properties of esterified starch, this study used EBI pretreatment to prepare glutaric anhydride (GA) esterified proso millet starch. GA starch did not show the corresponding distinct thermodynamics peaks. However, it had a high pasting viscosity and transparency (57.46–74.25 %). EBI pretreatment increased the degree of glutaric acid esterification (0.0284–0.0560) and changed its structure and physicochemical properties. EBI pretreatment disrupted its short-range ordering structure, reducing the crystallinity, molecular weight and pasting viscosity of glutaric acid esterified starch. Moreover, it produced more short chains and increased the transparency (84.28–93.11 %) of glutaric acid esterified starch. This study could offer a rationale for using EBI pretreatment technology to maximize the functional properties of GA modified starch and enlarge its implementation in modified starch.

Electron beam irradiation pretreatment enhances the formation of granular starch-phenolics complexes

Starch-phenolics complex generated by the interaction between starch and phenolic acids had improved characteristics than the native starch, but the efficient preparation of such complex is still challenging. In this study, we proposed a new method for the preparation of starch-phenolics complexes under the pretreatment of electron beam irradiation (EBI). Four structurally similar monomeric phenolic acids including gallic acid (GA), 3,4-Dihydroxy-5-methoxybenzoic acid (3MGA), syringic acid (SA) and vanillic acid (VA), which naturally existed in Tartary buckwheat (TB) seeds, were complexed with native and EBI-pretreated TB starch. The results showed that the complexation between starch and 3MGA was the strongest, more than 30 mg of 3MGA was complexed with 1 g of starch. The complexation did not affect the particle morphology and A-type structure of starch, but changed the crystal structure order and promoted the strength of hydrogen bond, which may lead to the formation of granular complex. EBI pretreatment can significantly promote the complexation by enhancing hydrogen bonds as indicated by a broader band at 3500 ∼ 3100 cm−1 in the FT-IR spectra. In addition, EBI pretreatment helped to build a tighter bond and higher crystallinity, increase the particle size and iodine binding capacity, and decrease turbidity to inhibit retrogradation of starch. The 1H NMR of complexes indicated that EBI pretreatment could provide more accessibility for starch to interact with phenolics by creating a spacious microenvironment for 1H (α1 → 4). Above all, EBI pretreatment enhanced the formations of starch-phenolics complexes.

Effects of electron beam irradiation pretreatment on the structural and functional properties of okara protein

The structural and functional properties of okara protein pretreated with electron beam irradiation (EBI) at different doses (0–10 kGy) were investigated. The results of Fourier transform infrared spectroscopy spectra and fluorescence spectra indicated that EBI treatment decreased the α-helix and β-sheet proportion, contributing to a less compact tertiary conformation, thereby increased the fluorescence intensity with a red shift of λmax. Scanning electron microscopy images indicated that okara protein was fragmented into smaller pieces and the surface was uneven with pores after EBI treatment. The solubility, thermal stability and emulsification characteristics of okara protein were regulated by modifying its structure by EBI treatment. When the EBI treatment dose was 6 kGy, the protein had the highest solubility, as well as emulsification characteristics. Taken collectively, these results demonstrate that EBI can improve the functional properties of okara protein, which may widen the application of the protein.

Techno-Economic Analysis of Electron Beam Irradiation Pretreatment of Corn Straw for Anaerobic Digestion

Techno-Economic Analysis of Electron Beam Irradiation Pretreatment of Corn Straw for Anaerobic Digestion

Electron beam irradiation enhanced extraction and antioxidant activity of active compounds in green walnut husk

Green walnut husk (GWH) contains abundant active compounds and is valued as a potential source of natural antioxidants. This study aimed at assessing the impact of electron beam irradiation (EBI) pretreatment on the extraction yield and antioxidant activity of active compounds in GWH. The ultrasonic extraction of active substances was optimized by response surface method (RSM). Scanning electron microscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction revealed physical structure changes in GWH powder. After EBI pretreatment, the content of polyphenols, flavonoids, and triterpenes in GWH increased by 18.88%, 43.00%, and 11.08%, respectively. Irradiation doses up to 30 kGy, DPPH, OH, and ABTS radical scavenging activity and reducing power of the crude extract were enhanced by 9.56%, 15.62%, 15.60%, and 36.98%, respectively. This was significantly different (P < 0.05) than the non-irradiated GWH. Therefore, EBI is a new pretreatment technology with potential application in the extraction and utilization of GWH.

Pretreatment and Bioprocess Trials in Various Reactor System on Lignocellulosic Biomass for Cellulosic Biomaterials

Pretreatment on lignocellulosic biomass prior to extraction of biomaterials, degradation of bioproduct, or production of biomaterial/bioproduct/biofuel, crucially influences the intended outcomes. The pretreatment of oil palm fronds (OPF), one of the most abundant agriculture residues in Malaysia, can be conducted based on the need of the methodology, either for small, lab, pilot, or industrial scales. In this article, examples of reactors for the pretreatment for instance microreactor (Bioshake iQ), conical shake flask, and mini-cylindrical reactor scale (fabricated) as well as the monitoring bioreactor (BlueSens Monitoring GmbH) reactor system dedicated for fermentation process using the outcome material from pretreatment process, are presented. All pretreatment trials with ionic liquid (IL) of 1-ethyl-3-methylimidazolium acetate [EMIM]Ac on OPF were conducted with a scaling-up strategy from micro-to-macro to fabricated reactors, monitoring Crystallinity Index (CrI) and Lateral Order Index (LOI). Electron beam irradiation pretreatment using 1000kGy was also tested in macroscale mode for CrI and LOI. Effectiveness of approximately 23 to 37% of CrI via microreactor experiments using 50, 70, and 90% v/v of [EMIM]Ac and at a temperature of 99oC was observed. Higher concentration of IL and temperature with nearly insignificance of solid loading of OPF in reaction liquid to the increase of the amorphous level of OPF was reported by macroscale mode in the 570-mL fabricated reactor. A short oxygen uptake rate (OUR) phase was observed in a 500-mL BlueSens shake flask with the real-time monitoring systems for 45-mL working volume, a nearly 10% of the total reactor volume for saccharification-fermentation using Escherichia coli K011 ATCC 55124 on approximately 2.22% w/v pretreated OPF from macroscale mode. Various data examples from these micro-to-macro scales including in a fabricated reactor system mode are crucially needed for further observations prior to pilot or industrial scales, needing a systematic data collection to be simulated and investigated in the future.

Structural changes and enzymatic hydrolysis yield of rice bran fiber under electron beam irradiation

The enzymatic hydrolysis yield of rice bran fiber (RBF) was enhanced by the electron beam irradiation (EBI) pretreatment. Furthermore, the compositional analysis, structural changes and the thermal stability of RBF and its lignocellulosic fractions (cellulose, hemicellulose and lignin) were investigated in this study. The content of cellulose was significantly (P<0.05) increased as the irradiation dose increased, ranging from 42.13% (0kGy) to 52.31% (300kGy). Conversely, the content of hemicellulose was decreased under the EBI pretreatment. The infrared spectra showed the breakage of the crystalline region of cellulose and the broken linkage between the lignin and hemicellulose. Additionally, the thermogravimetric analysis (TGA) proved that the thermal stability of the irradiated cellulose, lignin and hemicellulose was decreased when compared to the untreated samples. Particularly, the glucose yield of RBF achieved 34.99% at the irradiation dose of 250kGy. The EBI treatment is a promising technology to improve the enzymatic hydrolysis yield of RBF, making it potential to become an alternative material for bioenergy.

Study on enzymatic hydrolysis efficiency and physicochemical properties of cellulose and lignocellulose after pretreatment with electron beam irradiation

In lignocellulosic biomass biotransformation technology, pretreatment is the most important step to increase the conversion efficiency and reduce cost. The electron beam irradiation (EBI) pretreatment method was discussed in this study. First, the effects of a 0–1200 kGy irradiation dose on saccharification efficiency of lignocellulose biomass (birch) and analytically pure cellulose were studied. Then, the pretreated samples were tested for composition, X-ray diffraction, degree of polymerization, and Fourier transform infrared spectroscopy. Finally, the mechanism of the EBI pretreatment was analyzed from the aspects of lignin content, cellulose crystallinity, cellulose polymerization degree, and cellulose molecular structure. The results show that the EBI pretreatment can significantly improve the efficiency of enzymatic hydrolysis by degrading the lignin in lignocellulose, reducing the crystallinity and polymerization degree of cellulose, and destroying the cellulose molecules. It also obtained that the pretreatment of cellulose and lignocellulose with irradiation has a different trend in enzymatic hydrolysis efficiency with irradiation dose. This indicates that there is a difference in irradiation effects between pure cellulose and lignocellulose. And a possible degradation pathway of cellulose was proposed. This study has important guide for the application and development of EBI pretreatment methods.

Production of organic carboxylic acids by hydrothermal conversion of electron beam irradiation pretreated wheat straw

At present, wheat straw is comprehensively studied to produce chemicals and biofuels, such as bioethanol, biohydrogen, and biogas. In this study, we used wheat straw as raw material to produce organic carboxylic acids in NaIO4 + H2SO4, and electron beam irradiation (EBI) pretreatment was used in the process to enhance the efficiency of straw conversion. Scanning electron microscopy (SEM) images of raw and pretreated wheat straw showed that surfaces have been fractured after EBI pretreatment, and there were many micropores distributed in the pretreated straw. Moreover, the experimental results showed that EBI pretreatment can efficiently promote the transformation of wheat straw to organic carboxylic acids. Effects of irradiation dose, temperature, reaction time, the amount of sulfuric acid and sodium periodate on the yield of lactic acid (LA), formic acid (FA), and acetic acid (AA) were investigated. The highest LA yield of 34.37% was obtained at the optimum conditions (EBI 100 kGy, H2SO4 concentration 2 wt%, NaIO4 concentration 0.6 wt%, reaction time 45 min, reaction temperature 200 °C). And the yields of FA and AA were 29.16% and 10.39%, respectively. FT-IR analysis showed that hemicellulose, compared to cellulose and lignin, was partially removed after irradiation. The reaction pathways and mechanisms were inferred by analyzing the products of hydrothermal conversion of several intermediates.

Physicochemical properties of the electron beam irradiated bamboo powder and its bio-composites with PLA

The high cost and low toughness of Poly (lactic acid) (PLA) are the main drawbacks of PLA which limit its commercial applications. However, the cost of PLA can be reduced by incorporating it with various bio-based low-priced fillers. The bamboo powder (BP), lignocellulosic biomass, is promising green filler since it has high cellulose contents and no competition with food. However, its poor compatibility with the polymers reduces the mechanical properties of the resulting composite. Hence, this work investigates the electron beam irradiation pretreatment of bamboo powders. Further, the electron beam irradiated bamboo powder was blended with PLA in two different concentrations (5% and 10%) along with epoxide silane (3-Glycidoxypropyltrimethoxy silane) as a compatibilizer. The FT-IR, XRD, and TG/DTA analyses revealed that the irradiation demolishes aliphatic and aromatic moieties of bamboo powder followed by the formation of free radicals. The reduction in the intra and intermolecular hydrogen bonding among these moieties are also asserted. Moreover, mechanical and thermal properties of PLA/electron beam irradiated bamboo powder (PLA/EBP) composites are tested and obtained results have shown the improvement in the notched impact strength as well as stability in other mechanical and thermal properties. The compatibility and dispersion of the electron beam irradiated bamboo powder in the PLA matrix were analyzed by SEM studies. The hydrolytic degradation test of prepared composites was also performed.

Rapid and Continuous Preparation of Polyacrylonitrile-Based Carbon Fibers with Electron-Beam Irradiation Pretreatment.

Thermal stabilization is a critical, yet time- and energy-consuming process during the preparation of PAN-based carbon fibers. In this work, automobile-grade carbon fibers with a 2.85 GPa tensile strength and a 203 GPa modulus are continuously produced with electron-beam (e-beam) irradiation pretreatment and 24 min thermal stabilization. Thermal and structural analyses reveal that e-beam irradiation can lower the onset temperature of the cyclization reaction and mitigate the heat release. Meanwhile, during the process of stabilization, e-beam irradiation can facilitate the evolution of both the chemical structure and the crystalline structure of polyacrylonitrile (PAN) fibers. Comparing to the industrial production of carbon fiber with a 40 min stabilization time, e-beam irradiated PAN fibers can achieve the same degree of stabilization with a 40% time savings.

Enhancement of biodegradability of real textile and dyeing wastewater by electron beam irradiation

A textile and dyeing wastewater treatment plant is going to be upgraded due to the stringent discharge standards in Jiangsu province, China, and electron beam irradiation is considering to be used. In order to determine the suitable location of the electron accelerator in the process of wastewater treatment plant, the effects of electron beam (EB) irradiation on the biodegradability of various real wastewater samples collecting from the different stages of the wastewater treatment plant, the values of chemical oxygen demand (COD), biochemical oxygen demand (BOD5), and the ratio of BOD5 and COD (BOD5/COD), were compared before and after EB irradiation. During EB irradiation process, color indices and absorbance at 254nm wavelength (UV254) of wastewater were also determined. The results showed that EB irradiation pre-treatment cannot improve the biodegradability of raw textile and dyeing wastewater, which contains a large amount of biodegradable organic matters. In contrast, as to the final effluent of biological treatment process, EB irradiation can enhance the biodegradability to 224%. Therefore, the promising way is to apply EB irradiation as a post-treatment of the conventional biological process.

An irradiation-alkaline pretreatment of kenaf core for improving the sugar yield

Kenaf (Hibiscus cannabinus) has received considerable attention as a renewable resource because of its fast growth and low lignin content. In the present study, a combination pretreatment of kenaf core using electron beam irradiation (EBI) and dilute alkali was investigated to improve the sugar yield in enzymatic hydrolysis. In the first step, EBI of the kenaf core was performed at various doses ranging from 100 to 500 kGy. The electron beam-irradiated kenaf core was then autoclaved with 3% dilute alkali at 120 °C for 5 h. The pretreated kenaf core was finally subjected to enzymatic hydrolysis at 50 °C for 24, 48, and 72 h by Celluclast 1.5 L (70 FPU/mL) and Novozyme-188 (40 CbU/mL). A total sugar yield of 72.4% was obtained with a 63.9% yield of glucose from pretreated kenaf core after 72 h of enzymatic hydrolysis. To further analyze effectiveness of EBI pretreatment, characterizations of kenaf core by a two-step process of EBI-alkaline pretreatment were also investigated.