Antifungal and Antioxidant Properties of Chitosan Polymers Obtained from Nontraditional Polybius henslowii Sources

Abstract

Chitin was extracted from Polybius henslowii, a swimming crab, captured in large quantities throughout the Portuguese coast by purse seine vessels as bycatch. After standard chitin extraction procedures, water-soluble chitosan products were obtained via two different methods: (1) N-acetylation with the addition of acetic anhydride and (2) a reaction with hydrogen peroxide. The chemical structure and molecular weight of chitosan derivatives, water-soluble chitosan (WSC) and chitooligosaccharides (COS), were confirmed by Fourier Transform Infrared Spectroscopy (FT-IR) and gel permeation chromatography (GPC). Antioxidant and metal chelation activities were evaluated, and the growth inhibition capacity was tested on four phytopatogens. The chitooligosaccharides from pereopods (pCOS) and shell body parts (sCOS) inhibited all fungal species tested, particularly Cryphonectria parasitica with 84.7% and 85.5%, respectively. Both radical scavenging and antifungal activities proved to be dose-dependent. Chitooligosaccharides with a low molecular weight (2.7, 7.4, and 10.4 Kg·mol−1) showed the highest activity among all properties tested. These results suggested that chitosan derivatives from P. henslowii raw material could potentially be used against phytopathogens or as ingredient in cosmetics and other products related to oxidative stress.

Impact of Crystalline Structural Differences Between α- and β-Chitosan on Their Nanoparticle Formation Via Ionic Gelation and Superoxide Radical Scavenging Activities

“…The physicochemical properties of chitosan end products can be modulated by controlling factors such as chitin source of origin, reaction conditions (concentration, ratios of chitin to alkali, temperature), and extent of the reaction. It is known that hydroxyl, and amino groups in chitosan are key components in eliminating anion radicals such as superoxide and hydroxyl radicals [8][9][10]12] It has been reported that the amino and hydroxyl groups on chitosan backbone represent target moieties for chemical modifications to improve the aqueous solubility of chitosan since it is soluble only in an aqueous acidic solution, which is a major hurdle for its application [5]. The unique properties of chitosan, such as nontoxicity to humans [13][14][15]; commercial accessibility, biodegradability and biocompatibility [14,15], and high mucoadhesive properties [15,16] make chitosan an excellent choice for nanoparticle assembly.…”

Structural Characterization and Antioxidant Potential of Chitosan by γ-Irradiation from the Carapace of Horseshoe Crab

“…Peculiarly, XRD patterns for 10 kGy γ-ray-irradiated chitosan peaks at 2θ = 10.5°, 20.04°, and 21.9° with reflections were 20, 200, and 220 h, respectively. ( Figure 3 ), which was identical to non-irradiated chitosan [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 ]. However, when the 20 kGy γ-ray was used, an additional peak developed at 2θ = 10.5°.…”

“…A 37.33% (for 10 kGy) and 72.12% (20 kGy) increase was witnessed for DPPH activity with respect to the untreated sample (0 kGy). It has been reported that the antioxidant activity of chitosan increases with the increase of irradiation doses and decreases the M W [ 21 ]. It was reported that one of the mechanisms of chitosan is related to its scavenging activity, which can respond with free radical leftover free –NH 2 groups to form stable molecules and the –NH 2 groups can form ammonium groups ( ) by capturing a hydronium ion from the solution [ 32 ].…”

“…Since food and food-borne microbes are pH-sensitive, the ability of chitosan to regulate sodium ions in food makes it a suitable buffer that arrests microbial activity [ 14 ]. While γ-irradiation has the ability to modify chemical and physical properties of some polymeric materials [ 15 ], its ability to break polymeric chains promotes its use for improving the solubility of solvents [ 16 , 17 ] and stabilizing solutes [ 18 , 19 ] for antimicrobial [ 20 ] and antioxidant applications [ 21 ]. When γ-irradiation is applied to chitosan, the modification of chitosan molecules is thought to enhance the antimicrobial and antioxidant effects.…”

Effectiveness of Cymbopogon citratus Oil Encapsulated in Chitosan on Colletotrichum gloeosporioides Isolated from Capsicum annuum

“…Other studies indicated that the molecular weight and the degree of deacetylation affect the biological activity of chitosan. The inhibition of phytopathogens is partial in both products with higher degrees of chitooligosaccharides deacetylation or low deacetylation-Water-soluble chitosan products at the highest evaluated concentrations [ 18 ].…”