Poly(lactic acid) (PLA) is one of the most commonly employed synthetic biopolymers for facing plastic waste problems. Despite its numerous strengths, its inherent brittleness, low toughness, and thermal stability, as well as a relatively slow crystallization rate represent some limiting properties when packaging is its final intended application. In the present work, silver nanoparticles obtained from a facile and green synthesis method, mediated with chitosan as a reducing and stabilizing agent, have been introduced in the oligomeric lactic acid (OLA) plasticized PLA in order to obtain nanocomposites with enhanced properties to find potential application as antibacterial food packaging materials. In this way, the green character of the matrix and plasticizer was preserved by using an eco-friendly synthesis protocol of the nanofiller. The X-ray diffraction (XRD) and differential scanning calorimetry (DSC) results proved the modification of the crystalline structure as well as the crystallinity of the pristine matrix when chitosan mediated silver nanoparticles (AgCH-NPs) were present. The final effect over the thermal stability, mechanical properties, degradation under composting conditions, and antimicrobial behavior when AgCH-NPs were added to the neat plasticized PLA matrix was also investigated. The obtained results revealed interesting properties of the final nanocomposites to be applied as materials for the targeted application.

No abstract

Capparis spinosa aerial part and root extracts were prepared using solvents of varying polarity. Results showed that ethyl acetate extract (EAE) of the aerial part contains the highest concentration of phenolic compounds and flavonoids followed by the chloroform extract (CHE) of roots. The enzymatic methods were realised by the production of uric acid and reduction of cytochrome c. Result showed that all plant extracts were effective either in inhibiting the activity of XO or Cyt C. The IC50 ranges from 0.0226 ± 0.00019 to 4.32 ± 0.15g/l. The non enzymatic methods were conducted using in vitro techniques: In DPPH test, the radical scavenging activity for the root and aerial part extracts decreased in the following order CHE> EAE> CE and EAE> CE> CHE, respectively. In general the aerial part extracts had an antioxidant activity through ß-carotene-linoleate model system and ferric reducing ability greater than that of root part. In conclusion, Capparis spinosa appears to be a valuable plant and could be used to treat conditions where inhibition of XOR and free-radicals scavenging action are warranted.

No abstract

No abstract