Evaluation of the Rosemary Extract Effect on the Properties of Polylactic Acid-Based Materials

Abstract

New multifunctional materials containing additives derived from natural resources as powdered rosemary ethanolic extract were obtained by melt mixing and processed in good conditions without degradation and loss of additives. Incorporation of powdered rosemary ethanolic extract (R) into poly(lactic acid) (PLA) improved elongation at break, rheological properties, antibacterial and antioxidant activities, in addition to the biocompatibility. The good accordance between results of the chemiluminescence method and radical scavenging activity determination by chemical method evidenced the increased thermoxidative stability of the PLA biocomposites with respect to neat PLA, with R acting as an antioxidant. PLA/R biocomposites also showed low permeability to gases and migration rates of the bioactive compounds and could be considered as high-performance materials for food packaging. In vitro biocompatibility based on the determination of surface properties demonstrated a good hydrophilicity, better spreading and division of fibroblasts, and increased platelet cohesion. The implantation of PLA/R pellets, was proven to possess a good in vivo biocompatibility, and resulted in similar changes in blood parameters and biochemical responses with the control group, suggesting that these PLA-based materials demonstrate very desirable properties as potential biomaterials, useful in human medicine for tissue engineering, wound management, orthopedic devices, scaffolds, drug delivery systems, etc. Therefore, PLA/R-based materials show promising properties for applications both in food packaging and as bioactive biomaterials.

Influence of the Chitosan and Rosemary Extract on Fungal Biodegradation of Some Plasticized PLA-Based Materials

“…By plasticizing of PLA with PEG, the thermal characteristics resulted in a decrease of T g = 44.4 • C and a complex melting peak with two shoulders at 128.9 • C and 144.7 • C and average T m = 138.9 • C- Figure 9b. A high crystallinity degree was found of 28.15%, as also reported before in a previous study [56]. A shift in the glass transition was observed after fungi action at 50.3 • C in the case of PLA/PEG/14d/CG and at 59 • C in the case of PLA/PEG/14d/PC, respectively.…”

“…The FTIR spectra of PLA, PLA/R, PLA/PEG and PLA/PEG/R before and after being inoculated with Chaetomium globosum and Phanerochaete chrysosporium fungi are shown in Figure 8a, The general band assignments for PLA-based samples was done according to literature data [25,54,55] and are presented in Table 4. As revealed in our previous studies [29,30,56], neat PLA exhibits sharp bands assigned to vibrations of carbonyl group, νC=O, with a maximum at 1749 cm −1 (stretching) and at 1266 cm −1 (bending). The absorption bands of native PLA are also noticed in the spectrum of the fungal-biodegraded PLA but slightly shifted to higher wavenumbers and with changes in intensities, and new bands also appears.…”

Development of Bionanocomposites Based on PLA, Collagen and AgNPs and Characterization of Their Stability and In Vitro Biocompatibility

“…It is observed that the silver nanoparticles block the oxidation of free radicals and the stability is improved. The same effect was observed in the case of introduction the natural phenolic antioxidants like powdered rosemary ethanolic extract into the PLA matrix [39]. The literature shows the evaluation of antioxidant efficacy of synthesized AgNPs using 1,1-diphenyl-2-picryl hydrazyl radical (DPPH) [40], H 2 O 2 [41], ABTS radical cation scavenging, and FRAP assays [42].…”

Preparation and evaluation of antioxidant packaging films made of polylactic acid containing thyme, rosemary, and oregano essential oils

“…Darie‐Nita et al () prepared PLA films with and without Polyethylene glycol as plasticizer with the addition of 0.25%–0.75% powdered rosemary ethanolic extract using compression molding. Film radical scavenging activity was evaluated using the ABTS method.…”

“…It is probable that this small increase may be owed to the higher activity of pure thymol as a plasticizing agent compared to the multi‐component EOs used in the present study. Finally, Darie‐Nita et al () developed polylactic acid‐based films incorporating ethanolic rosemary extracts by melt mixing/compression molding. The addition of 0.25%–0.75% rosemary extract to neat PLA resulted in a small increase in tensile strength and a small decrease in percentage elongation at break.…”