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The hybrid composite sample based on Prosopis Juliflora (PJ) bark and ramie fibre with different length, weight percentage, and curing temperature were created for the first time in this work. Totally, 120 hybrid composite samples were tested in this study. There were five different fibre lengths: 10 mm, 15 mm, 20 mm, 25 mm, and 30 mm, weight percentages 10 %, 20 %, 30 %, 40 %, and 50 %, and different curing temperatures 80 °C, 90 °C, 100 °C, 110 °C, and 120 °C used to produce the hybrid composite samples. Due to the cross-linking ability with the epoxy matrix, the hybrid composite specimen shows high resistance up to 98 Shore D hardness. The high polarity of the epoxy matrix and the hydrogen bond strengthening effect, increased the composite sample flexural strength by 12 %. The curing temperature of 100 °C, 20 mm fibre length, and 30 % of the hybrid composite sample achieved the highest tensile strength (28.76 MPa), flexural strength (46.54 MPa), impact strength (4.5 J), and hardness strength properties (98 shore D). Thermo gravimetric analysis (TGA) revealed the composite samples initial decomposition temperature (T i ) at 98 °C, maximum decomposition temperature (T max ) at 320 °C, and the final decomposition temperature (T f ) at 466 °C., 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 © 2024 Elsevier B.V. All rights reserved.)

The present study explored the use of chitosan films functionalized with antioxidants extracted from Larix decidua Mill. bark for active packaging. The pristine chitosan and extract-incorporated chitosan films were evaluated for their structural, physico-mechanical, thermal, viscoelastic and antioxidant properties using advanced characterization techniques. The infrared spectroscopy revealed hydrogen bonding between the extract polyphenolic antioxidants and chitosan, whereas the surface microscopy studies indicated good compatibility between them. The addition of bark extract caused a significant increase in color parameters and solubility with reduction in swelling and elongation at break of the films. The thermal analysis indicated a drop in thermal stability of chitosan films modified with the extract. The dynamic mechanical analysis confirmed the extract-polymer interactions and the viscoelastic nature of the films. The incorporation of bark extract caused remarkable enhancement in the antioxidant activity of chitosan films. Overall, larch bark extract-functionalized chitosan films demonstrated promising potential for food packaging., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

The present study described the optimization of the extraction process with carbon dioxide in supercritical state for obtaining extractives, especially polyphenols from softwood bark, Norway spruce ( Picea abies (L.) Karst.). Using a full 2 3 factorial design of experiments, the effect of varying the working parameters on the yield of extractives was studied for the following ranges: temperature 40-100 °C, pressure 1050-9000 psi (7.2-62 MPa), and concentration of EtOH/water co-solvent mixture 40-96.6%. In addition, total phenolics content and the antioxidant capacity of the spruce bark extract were determined. The optimum operating conditions for the yield of extractives were identified as 73 °C, 6465 psi (44.5 MPa), and 58% EtOH/water cosolvent concentration for a yield of 8.92%. The optimum conditions for achieving a total phenolics content of 13.89 mg gallic acid equivalent (GAE)/g dry extract were determined as: 45 °C, 1050 psi (7.2 MPa), and 96.6% EtOH/water mixture.

Softwood bark is an important source for producing chemicals and materials as well as bioenergy. Extraction is regarded as a key technology for obtaining chemicals in general, and valorizing bark as a source of such chemicals in particular. In this paper, properties of 237 compounds identified in various studies dealing with extraction of softwood bark were described. Finally, some challenges and perspectives on the production of chemicals from bark are discussed., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Study on the EtOAc soluble fraction from the bark of Populus ussuriensis Kom. resulted in the isolation of three phenolic glycosides, including populoside (1), 7-O-ρ-coumaroylsalirepin (2) and 7-O-caffeoylsalirepin (3), among which 3 is a new compound. The structures of these compounds were elucidated on the basis of spectroscopic evidence. Phenolic glycosides 1-3 exhibited excellent antioxidant activity, evaluated in the ABTS⁺ radical scavenging assay.