title: Antioxidant and antimicrobial proprieties of chitin and chitosan extracted from Parapenaeus Longirostris shrimp shell waste.
abstract: BACKGROUND
  Chitosan, the linear polymer, is produced by alkali deacetylation of chitin (CHI). Recently chitin and chitosan were attracted marked interest due to their biocompatibility, biodegradability and non-toxicity.
  
  
  METHODS
  In this study, chitin was extracted from shrimp shell (Parapenaeus longirostris) and chitosan was deacetylated by classical and ultrasound-assisted method. The identification of functional groups and the determination of degree of deacetylation of chitin (CHI), classical deacetylated chitosan (CDC) and ultrasound-assisted deacetylated chitosan (UDC) were carried through Fourier Transform-Infrared Spectroscopy. Their antimicrobial and antioxidant activity were also investigated.
  
  
  RESULTS
  The degree of deacetylation of CHI, CDC and UDC is 33.64%, 73.68% and 83.55%, respectively. Results showed that CHI, CDC and UDC exhibited a good antimicrobial activity against (S. aureus, E. coli, P. aeruginosa, K. pneumonia) and (C. albicans and C. parapsilosis). The scavenging ability of CHI, CDC and UDC on 1,1-diphenyl-2-picrylhydrazyl radicals is ranging from 4.71% to 21.25%, 11.45% to 32.78% and 18.27% to 44.17%, respectively, at the concentrations of 0.25 to 1mg/mL. The inhibition of lipid peroxidation with thiobarbituric acid-reacting substances is ranging from 11.7% to 51.63%, 17.24% to 63.52% and 29.31% to 77.39%, respectively, at varying concentrations of 0.25 to 1mg/mL.
  
  
  CONCLUSIONS
  The effectiveness of CHI, CDC and UDC is correlated with their degree of deacetylation. The results indicate the possibility of exploiting chitin and chitosan as antimicrobial agent.
authors.affiliation: University of Sousse, Department of Biochemistry, Faculty of Medicine Sousse, 4002 Sousse, Tunisia. Electronic address: Jawhar_hafsa@yahoo.fr.
authors.forename: J
authors.initials: J
authors.lastname: Hafsa
authors.affiliation: University of Sousse, Department of Biochemistry, Faculty of Medicine Sousse, 4002 Sousse, Tunisia.
authors.forename: M A
authors.initials: MA
authors.lastname: Smach
authors.affiliation: University of Sousse, Department of Biochemistry, Faculty of Medicine Sousse, 4002 Sousse, Tunisia.
authors.forename: B
authors.initials: B
authors.lastname: Charfeddine
authors.affiliation: University of Sousse, Department of Biochemistry, Faculty of Medicine Sousse, 4002 Sousse, Tunisia.
authors.forename: K
authors.initials: K
authors.lastname: Limem
authors.affiliation: University of Monastir, Laboratory of interfaces and advanced materials, Faculty of Monastir, Monastir 5000, Tunisia.
authors.forename: H
authors.initials: H
authors.lastname: Majdoub
authors.affiliation: University of Sousse, Department of Biochemistry, Faculty of Medicine Sousse, 4002 Sousse, Tunisia.
authors.forename: S
authors.initials: S
authors.lastname: Rouatbi
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects; D002686:Chitin / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D048271:Chitosan / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D005658:Fungi / Q000187:drug effects; D015227:Lipid Peroxidation / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D033561:Penaeidae / Q000737:chemistry*
chemical_list: D000890:Anti-Infective Agents; D000975:Antioxidants; D002686:Chitin; D048271:Chitosan
keywords: Antimicrobial; Antimicrobien; Antioxidant; Antioxydant; Chitin; Chitine; Chitosan; Chitosane; Ultrason; Ultrasound