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Starch has great potential to replace petroleum-based plastics in food packaging applications. However, starch films often exhibit poor mechanical and barrier properties, and are vulnerable to moisture and bacterial contamination. This study proved that the incorporation of eggshell powder (ES) enhanced the hydrogen bonding in starch-based films significantly, which contributed to improved tensile strength, Young's modulus, and water resistance of the films. The performance of ES-incorporated films could be optimized by adjusting the size, concentration, and surface property of ES in the film matrix. Notably, adsorbing epigallocatechin gallate (EGCG) on the surface of porous ES contributed to enhanced dispersibility of the fillers in the film matrix, which increased the tortuous path of light, water vapor, and oxygen have to take through the films, resulting in increased UV screening performance, water vapor and oxygen barrier property of the films by 60 %, 7.2 %, and 27.9 %, respectively. Meanwhile, loading EGCG in ES also enable superior antibacterial activity of the final films. This study suggests that eggshell fillers offer a sustainable means of improving the functional performance of starch-based films, which may increase their application as packaging materials in the food industry., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

In this work, steam explosion (SE) was exploited as a potential hydrothermal-humification process of vegetable wastes to deconstruct their structure and accelerate their decomposition to prepare humified substances. Results indicated that the SE process led to the removal of hemicellulose, re-condensation of lignin, degradation of the cellulosic amorphous region, and the enhancement of thermal stability of broccoli wastes, which provided transformable substrates and a thermal-acidic reaction environment for humification. After SE treatment, total humic substances (HS), humic acids (HA s ), and fulvic acids (FA s ) contents of broccoli samples accounted for up to 198.3 g/kg, 42.3 g/kg, and 166.6 g/kg, and their purification were also facilitated. With the increment of SE severity, structural characteristics of HA s presented the loss of aliphatic compounds, carbohydrates, and carboxylic acids and the enrichment of aromatic structures and N-containing groups. Lignin substructures were proved to be the predominant aromatic structures and gluconoxylans were the main carbohydrates associated with lignin in HA s , both of their signals were enhanced by SE. Above results suggested that SE could promote the decomposition of easily biodegradable matters and further polycondensation, aromatization, and nitrogen-fixation reactions during humification, which were conducive to the formation of HA s .

Solar steam generation is one of the most promising technologies for desalination. In order to further promote the development of solar steam generation, a double-layer cellulose hydrogel (DCH) was designed and used as solar steam generation for seawater desalination. Under one sun illumination intensity (1 kW·m -2 ), the average evaporation rate and the steam evaporation efficiency reaches 1.582 kg·m -2  h -1 and 91.4 %, respectively. The durability test was performed to verify the long-time durability and antifouling property. Outdoor experiment was carried out to prove the high steam evaporation efficiency and desalination performance of DCH. This paves a way for the cellulose-based hydrogel as a biodegradable, low-cost and promising solar steam generation., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

In this work, steam explosion (SE) was exploited as a green and facile process to deconstruct liquorice's structure and deglycosylate glycyrrhizic acid (GL) to improve conversion and diffusion efficacy of GL and its hydrolyzed products. Results showed SE induced auto-hydrolysis of GL into glycyrrhetic acid 3-O-mono-β-D-glucuronide (GAMG) and glycyrrhetinic acid (GA), by which 30.71% of GL conversion, 5.24% and 21.47% of GAMG and GA formation were obtained. GL hydrolytic pathways were revealed by reaction kinetics and thermodynamics, which possessed complex consecutive and parallel reactions with endothermic, non-spontaneous and entropy-decreasing features. SE referred to cause cleavage of the β-1,3 glycosidic bond in GL which was hydrolyzed to GA as a main product and GAMG and glucuronic acids as minor products. Diffusion of hydrolyzed products was accelerated by raising the diffusion coefficient and shortening the equilibrium time by over 90%. This work provides a sustainable and efficient route for product conversion and function enhancement of bioactive components., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

High performance poly(vinyl alcohol) (PVA)/lignin nanomicelle (LNM) nanocomposite films with good vapor barrier and advanced UV-shielding properties were fabricated in this study. LNM was homogeneously distributed in the PVA matrix and strong robust hydrogen bonds were successfully constructed between LNM and PVA matrix. With only 5 wt% loading of LNM into the PVA/LNM nanocomposite, the water vapor transmission rate (WVTR) was declined by about 189% compared with pure PVA. Moreover, after introducing lignin, the PVA nanocomposite films showed improved tensile strength and toughness, excellent UV-blocking and good thermal stability. As both lignin and PVA are biodegradable, this study shows a meaningful design approach for biodegradable functional nanocomposite films using cheap and easily available biomass and biodegradable raw materials., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Nanofibrillated cellulose (NFC) easily forms a high strength film but is unable to withstand the influence of water vapor when used in high moisture situations. The water vapor transmission rate (WVTR) of a NFC film was as high as 5088 g/m(2)24h (38 °C, 90% RH). The addition of beeswax latex in a NFC casting film (NFX) lowered the WVTR to 3918 g/m(2)24h. To further reduce the WVTR, a coating agent comprised of acrylated epoxidized soybean oil (AESO) and 3-aminopropyltriethoxysilane (APTS) was applied onto the NFX film using a rod coater. A combination of the suitable AESO/APTS ratio, initiator dosing, curing time and temperature could reduce the WVTR to 188 g/m(2) 24h when the coat weight was 5 g/m(2). Moreover, the coated NFX film was highly hydrophobic along with the improved transparency and thermal stability. This biodegradable polymer-coated NFC film can be used as potential packaging barrier in certain areas., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Steam explosion and steam pre-treatment have proved capable of enhancing enzymatic saccharification of lignocellulosic materials. However, until now, these methods had not been compared under the same operational conditions and using the same raw material. Both pre-treatments lead to increased yields in the saccharification of Eucalyptus globulus; but results have been better with steam pre-treatments, despite the more accessible surface of exploded samples. The reason for this finding could be enzymatic inhibition: steam explosion causes a more extensive extraction of hemicelluloses and releases a greater amount of degradation products which can inhibit enzymatic action. Enzymatic inhibition is also dependent on the amount and chemical structure of lignin, which was also a contributing factor to the lower enzymatic yields obtained with the most severe pre-treatment. Thus, the highest yields (46.7% glucose and 73.4% xylose yields) were obtained after two cycle of steam treatment, of 5 and 3 min, at 183°C., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

In order to overcome the deficiencies of single layer coating, bilayer coated papers were prepared by two separate coating procedures using various combinations of proteins or polysaccharides with beeswax. Among those combinations, chitosan-beeswax bilayer coated paper showed the best water vapour barrier property. It was observed that as the concentration of chitosan solution increased from 1.0 to 3.0 wt%, its water vapour transport rate (WVTR) decreased from 171.6 to 52.8 g/m(2)/d but using reduced beeswax coating weight (from 10.1 to 4.9 g/m(2)). It also displayed an enhanced performance of grease resistance. Scanning electron microscopy (SEM) showed that beeswax layer was fitted to chitosan layer so closely that these two layers are indistinguishable. Confocal laser scanning microscope (CLSM) further confirmed the existence of an integrated chitosan film between beeswax layer and paper base and a thin composite layer consisting of chitosan and beeswax., (Copyright © 2013 Elsevier Ltd. All rights reserved.)