Influence of chitosan source and degree of deacetylation on antibacterial activity and adsorption of AZO dye from water

Abstract

Chitosan is one of the most abundant biopolymers in nature with high economic value due to its biocompatibility, biodegradability, lack of toxicity, and antifungal activity. In this study, chitosan was extracted from three different sources: Blaps lethifera (CSB), Pimelia fernandezlopezi (CSP), and Musca domestica (CSM). The ash content (AC), moisture content (MC), fat binding capacity (FBC), water binding capacity (WBC), and deacetylation degree (DD) were determined for the prepared chitosans. The effect of the DD of chitosan on the antibacterial activity of gram (positive/negative) bacteria and the azo dyes (methylene blue, MB) removal from wastewater was also investigated. Chitosan extracts showed good antibacterial activity against Listeria innocua, Bacillus subtiliis, Staphylococcus aureus, Salmonella typhimurium, and Pseudomonas aeruginosa. The MB dye removal of CSB-chitosan, CSP-chitosan, and CSM-chitosan reached 37%, 87%, and 26%, respectively, at a contact time of 2 h, a low initial dye concentration MB of 13 ppm, a solution temperature of 25 °C, and a pH = 7. Graphical Abstract

Physicochemical Properties and Release Study of Antimetabolite-Incorporated Stearoyl Chitosan

“…Degree of substitution (DS) and DD refer to the degree of substitution and the degree of deacetylation, respectively . The value of DD was determined based on the ratio of A 1655 / A 3450 , as given in the equation below DD false( % false) = true( A 1655 A 3450 × 100 1.33 ) where A 1655 , A 3450 , and 1.33 correspond to absorbance values at 1655 cm –1 due to CO (amide I), band at 3450 cm –1 owing to the O–H band, and the assumption for fully deacetylated chitosan, respectively.…”

“…where A 1655 , A 3450 , and 1.33 correspond to absorbance values at 1655 cm −1 due to C�O (amide I), band at 3450 cm −1 owing to the O−H band, and the assumption for fully deacetylated chitosan, 42 respectively.…”

Biopolymers for enhancement of bone regeneration

“…Lastly, biopolymers are biodegradable polymers that may be derived from plant or animal sources but are not always. Additionally, they may originate from bacterial or natural sources [13,14] . Tissue engineering makes extensive use of polymers, which are often categorized as natural or synthetic.…”

Chitosan as a tissue engineering scaffold

“…Chitosan is a linear copolymer of 2-amino-2-deoxy-D-glucopyranose and 2-acetamido-2deoxy-D-glucopyranose that is -(1-4) connected. The exoskeletons of insects, crustaceans, and fungi are the natural sources of chitosan, which has been found to be biocompatible and biodegradable [7,8] .…”