International Journal of Biological Macromolecules 104 (2017) 854–861 Contents lists available at ScienceDirect International Journal of Biological Macromolecules j ourna l ho me pa g e: www.elsevier.com/locate/ijbiomac Fungal chitosan and Lycium barbarum extract as anti-Listeria and quality preservatives in minced catfish Mohammed S. Alsaggaf a , Shaaban H. Moussa a,b , Nihal M. Elguindy c , Ahmed A. Tayel d,∗ a College of Science and Humanitarian Studies, Shaqra University, Qwaieah 11971, Saudi Arabia b Genetic Engineering and Biotechnology Research Institute, University of Sadat City, Egypt c Department of Biochemistry, Faculty of Science, Alexandria University, Egypt d Faculty of Aquatic and Fisheries Sciences, Kafrelsheikh University, Egypt a r t i c l e i n f o Article history: Received 11 April 2017 Received in revised form 21 June 2017 Accepted 23 June 2017 Available online 24 June 2017 Keywords: Antimicrobial Antioxidation Biopreservation Mode of action Sensory evaluation a b s t r a c t Listeria monocytogenes is a foodborne bacterial pathogen that causes serious health risks. Chitosan (Ch) is a bioactive polymer that could be effectively applied for foodstuffs biopreservation. Lycium barbarum (Goji berry) is ethnopharmaceutical fruit that have diverse health protecting benefits. Chitosan was pro- duced from A. niger and employed with L. barbarum extract (LBE) as blends for Listeria control and quality biopreservation of African catfish mince (Clarias gariepinus). Chitosan could utterly control L. monocyto- genes survival in fish mince and its efficacy was strengthened with added LBE at 0.2 and 0.4%. Blending of fish mince with Ch could effectively reduce the progress of chemical spoilage parameters and this pro- tective effect was greatly enhanced with increased addition of LBE. The sensorial assessment of treated minces indicated panelists preferences for the entire attributes of blended samples with Ch and LBE, particularly with storage prolongation. Scanning micrographs elucidated the antibacterial action of Ch against L. monocytogenes. Results recommended the application of fungal Ch/LBE composites as biop- reservatives and anti-listerial agents, through their blending with catfish mince, to eliminate bacterial growth, enhance sensory and storage attributes of preserved fish. © 2017 Elsevier B.V. All rights reserved. 1. Introduction Listeria monocytogenes, the foodborne bacterial pathogen with major health risk, is the principal causative agent of listeriosis dis- ease, which could have a fatality rate of ∼30% [1,2]. L. monocytogenes is a psychrotrophic and facultatively anaerobic microbe that was associated with many mortality and morbidity outbreaks, mainly involved fast and processed foods [3]. The ability of L. monocyto- genes to survive under refrigeration temperature make it a very serious threat toward preserved animal foods [2]. Many listeriosis outbreaks, associated with consumption of seafood and processed fish, were reported [3–5]. The production and cultivation of Clarias gariepinus (African cat- fish) is popularly increased in several countries, including Egypt, because of the desirable characteristics of this fish, e.g. resistance to inappropriate propagation conditions, rapid growth rate, ease of harvesting, nutritional requirements and cost effectiveness. How- ∗ Corresponding author at: Faculty of Aquatic and Fisheries Sciences, Kafrelsheikh University, El-Geish St 33516, Kafrelsheikh City, Egypt. E-mail address: tayel ahmad@yahoo.com (A.A. Tayel). ever, despite of their low price and abundant supply, the marketing of these fish is still comparatively insufficient; African catfish (fresh, cooked or grilled) were classifies as from the less preferred and less consumed fish species [6]. It was recommended to subject the complete fish to further processing, e.g. minced or surimi-based products, to become more marketable and commercialized [7]. Chitosan, the deacetylated chitin derivative, is a very promising biopolymer that may be naturally found in nature and could be pro- duced in commercial scale from the chemical treatment of natural chitin, from crustaceans’ shells. Chitosan was successfully pro- duced from another auspicious source, e.g. fungal species mycelia, as renewable, stable, cost effective and high quality sources [8–10]. Because of their superior antimicrobial activity, fungal chitosan types were efficaciously applied as powerful protectants from the attach of various foodborne bacterial pathogens found in water, animal and plant foodstuffs [11–14]. Furthermore, the usage of fungal chitosan, and its composites with plant extracts, was highly recommended for extending the shelf life and maintaining the overall qualities of many foodstuffs including meat, fruits and fish through blending with minced food or covering with their edible coatings [10,11,15,16]. http://dx.doi.org/10.1016/j.ijbiomac.2017.06.097 0141-8130/© 2017 Elsevier B.V. All rights reserved.