Laccase-mediated functionalization of chitosan by caffeic and gallic acids for modulating antioxidant and antimicrobial properties

A new strategy for the functionalization of chitosan with caffeic acid (CA) or gallic acid (GA) using laccase from Trametes versicolor is presented for the first time, yielding a product with modulated antioxidant and antimicrobial properties. UV-vis spectroscopy coupled to HPLC-SEC analysis and cyclic voltammetry kinetic studies showed that laccase catalyzes the oxidation of phenolic acids to electrophilic o-quinones, which undergo new oligomer/polymer-forming structures originated by C-C coupling between the benzene rings and C-O-C coupling involving phenolic side-chains. Furthermore, pH tunable reactions/interactions of the laccases oxidized o-quinones with nucleophilic amino groups of chitosan were determined with FTIR and ¹H NMR spectroscopy's. The highest antioxidant activity was found to be for chitosan modified with phenolic acids at pH 4.5, exhibit also an increased activity against Escherichia coli and Listeria monocytogenes compared to untreated chitosan.     

Sulfonation of papain-treated chitosan and its mechanism for anticoagulant activity

The novel low-molecular-weight chitosan polysulfate (MW 5120-26,200 Da) was prepared using the depolymerization of chitosan with papain (EC. 3.4.22.2). The sulfonation of depolymerized products was performed using chlorosulfonic acid in N,N-dimethylformamide under semi-heterogeneous conditions. The structures of the products were characterized by FTIR, ¹³C NMR, and ¹H NMR (1D, 2D NMR) spectroscopy. The present study sheds light on the mechanism of anticoagulant activity of chitosan polysulfate. Anticoagulant activity was investigated by an activated partial thromboplastin assay, a thrombin time assay, a prothrombin time assay, and thrombelastography. Surface plasmon resonance also provided valuable data for understanding the relationship between the molecular binding of sulfated chitosan to two important blood clotting regulators, antithrombin III and heparin cofactor II. These results show that the principal mechanism by which this chitosan polysulfate exhibits anticoagulant activity is mediated through heparin cofactor II and is dependent on polysaccharide molecular weight.     

New chitin,chitosan, and O-carboxymethyl chitosan sources from resting eggs of Daphnia longispina (Crustacea); with physicochemical characterization,and antimicrobial and antioxidant activities

The paper describes the isolation and characterization of chitin and chitosan from Daphnia longispina resting eggs harvested from a reservoir. Resting eggs are fertilized eggs that are encased in chitinous shells called ‘ephippia’ and which ensure the survival of the Daphnia population in adverse conditions. The chitin-content of D. longispina resting eggs was found to be 23 ～ 25% and the chitosan (having a 70 ～ 75% deacetylation degree) yield of the chitin was 76 ～ 77%. This high chitin-content indicates that D. longispina resting eggs can be exploited as a chitin source. The structure and thermal properties of chitin, extracted from D. longispina resting eggs, were characterized by employing Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction and scanning electron microscopy. The crystallinity of the chitin was found to be very low (48%). Physicochemicallycharacterized chitosan and the produced O-carboxymethyl chitosan were tested for their antimicrobial and antioxidant activity. It has been observed that chitosan displays antimicrobial activity against all pathogenic bacteria, whereas O-carboxymethyl chitosan only exhibits inhibition activity against L. garvieae, L. Monocytogenes ATCC 7644, Y. enterocolitica NCTC 11175 and S. aureus ATCC 25923. In a free radical scavenging activity assay, the IC₅₀ values of chitosan, O-carboxymethyl chitosan and butylated hydroxytoluene were found to be 23.01, 56.43 and 0.05, respectively. The ferric-reducing power of O-carboxymethyl chitosan (EC₅₀ = 8.30) indicated higher activity than chitosan (EC₅₀ = 10.12).     

Growth inhibitory effect on bacteria of chitosan membranes regulated with deacetylation degree

Antibacterial activity of chitosan membranes was investigated by a conductimetric assay using a Bactometer. The purpose of this investigation was to produce a practical, high-performance membrane for separation engineering. The antibacterial activity of powdered chitosan membrane was evaluated by the minimal inhibitory concentration (MIC). The MIC for Escherichia coli was almost 200 (mg-chitosan/ml-bacterial suspension), and for Staphylococcus aureus it was 40 (mg-chitosan/ml-bacterial suspension). Growth of the gram-positive sample (S. aureus) was more strongly inhibited by chitosan than the gram-negative sample (E. coli). This inhibitory effect was recognized as a bactericidal effect. Antibacterial activity was also observed and depended on the shape and the specific surface area of the powdered chitosan membrane. The influence of the deacetylation degree (DD) of the chitosan on inhibiting the growth of S. aureus was investigated by two methods: incubation using a mannitol salt agar medium, and a conductimetric assay. By both methods, chitosan with a higher DD successfully inhibited growth of S. aureus. Our findings regarding the dominant role of the DD of chitosan will be useful for designing long-life, hygienic, membrane-based processes.     

Preparation of N-vanillyl chitosan and 4-hydroxybenzyl chitosan and their physico-mechanical, optical, barrier, and antimicrobial properties

Chitosan derivatives such as N-vanillyl chitosan and 4-hydroxybenzyl chitosan were prepared by reacting chitosan with 4-hydroxy-3-methoxybenzaldehyde (vanillin) and 4-hydroxybenzaldehyde. Amino groups on chitosan reacts with these aldehydes to form a Schiff base intermediate, which is later on converted into N-alkyl chitosans by reduction with sodium cyanoborohydride. The chemical reaction was monitored by ¹H NMR spectroscopy and the absence of aldehydic proton at 9.83 ppm in NMR spectra was observed for both the modified chitosan derivatives confirming the reaction. Modified chitosan films were later prepared by solution casting method and their physico-mechanical, barrier, optical and thermal properties were studied. The results clearly indicated significant change in tensile strength, water vapour transmission rate, and haze properties of modified chitosans. Modified chitosan films were also studied for their antimicrobial activity against Aspergillus flavus. The results showed a marked reduction of aflatoxins produced by the fungus in the presence of the N-vanillyl chitosan and 4-hydroxybenzyl chitosan film discs to 98.9% and non-detectable levels, respectively.     

A mediator-free glucose biosensor based on glucose oxidase/chitosan/α-zirconium phosphate ternary biocomposite

A novel glucose oxidase/chitosan/α-zirconium phosphate (GOD/chitosan/α-ZrP) ternary biocomposite was prepared by co-intercalating glucose oxidase (GOD) and chitosan into the interlayers of α-zirconium phosphate (α-ZrP) via a delamination–reassembly procedure. The results of X-ray diffraction, infrared spectroscopy, circular dichroism, and ultraviolet spectrum characterizations indicated not only the layered and hybrid structure of the GOD/chitosan/α-ZrP ternary biocomposite but also the recovered activity of the intercalated GOD improved by the co-intercalated chitosan. By depositing the GOD/chitosan/α-ZrP biocomposite film onto a glassy carbon electrode, the direct electrochemistry of the intercalated GOD was achieved with a fast electron transfer rate constant, k_s, of 7.48 ± 3.52 s⁻¹. Moreover, this GOD/chitosan/α-ZrP biocomposite modified electrode exhibited a sensitive response to glucose in the linear range of 0.25–8.0 mM (R = 0.9994, n = 14), with a determination limit of 0.076 mM.     

Laccase-catalysed protein–flavonoid conjugates for flax fibre modification

The introduction of flavonoid compounds into proteins can improve the natural properties of proteins, being promising products which essentially require antioxidant property. The oxidative conjugation of protein–flavonoids was processed by laccase catalysis resulting in the synthesis of biologically functional polymers. The new reaction products were detected in terms of sodium dodecyl sulfate polyacrylamide gel electrophoresis and matrix-assisted laser desorption/ionisation-time of flight mass spectra, showing a greater molecular weight formation. Their characterisations were further carried out in terms of UV–Vis spectroscopy, photon correlation spectroscopy, differential scanning calorimetry and Fourier transform infrared (FT-IR) spectroscopy analysis. In addition, their application of protein–flavonoid conjugates onto flax fibres was exploited to supplement a suitable microorganism environment of protein-possessed fibres. The anchoring of conjugates onto cationised fibres was successfully performed by ionic interaction with negatively charged proteins. The level of anchoring efficiency was quantified in terms of measuring colour strength (k/s) and fluorescence microscopy analysis. The conjugates onto fibres presented acceptable durability in terms of washing resistance and the surface became hydrophilic when α-casein–catechin was applied (lower contact angle 48°). By the anchoring of protein–flavonoid conjugates onto flax fibres, the final products with new colour generation and antioxidant activity (>93%) were obtained.     

Foliar spraying of elicitors in pear trees induced resistance to Cacopsylla bidens

The pear psylla, Cacopsylla bidens (?ulc, 1907) (Psylloidea, Psyllidae, Psyllinae) is a serious pest of pear worldwide. In this research, the effects of salicylic acid (SA), chitosan, γ-aminobutyric acid (GABA), and Serenade Aso (Bacillus subtilis QST713) were studied on the induced resistance of pear trees to C. bidens. The treatments showed a significant difference in terms of population growth of C. bidens after 7 and 14 days during two years. In 2019, the mean population growth of total life stages of C. bidens in the studied treatments was significantly lower than control after 7 and 14 days of spraying. In 2020 (7 and 14 days after spraying), the percent decline in the mean population of pear psylla (total life stages) was highest on chitosan treatment (75 and 85 %, respectively) and the lowest on control (30 and 48 %, respectively). GC–MS analysis revealed the range of chemicals in the pear leaves under different treatments. Based on the results, 23 compounds were identified, including 9 alkaloids, 6 flavonoids, 4 polyphenols, 3 terpenoids, and one glycoside. In all treatments except Serenade, the amounts of alkaloids increased compared to the control. Furthermore, the activity of catalase and glutathione S- transferase enzymes in C. bidens under chitosan treatment was significantly higher than others; but the activity of peroxidase significantly decreased on chitosan compared to SA and GABA. The lower levels of peroxidase in C. bidens reared on trees treated with chitosan indicate this insect has not been able to detoxify plant secondary metabolites effectually. In addition, our findings suggested that chitosan on pear trees could act effectively in reducing the C. bidens population and can be considered in integrated management programs of this pest.     

Characterization and antimicrobial activity of water-soluble N-(4-carboxybutyroyl) chitosans against some plant pathogenic bacteria and fungi

Water-soluble N-(4-carboxybutyroyl) chitosan derivatives with different degrees of substitution (DS) were synthesized to enhance the antimicrobial activity of chitosan molecule against plant pathogens. Chitosan in a solution of 2% aqueous acetic acid-methanol (1:1, v/v) was reacted with 0.1, 0.3, 0.6 and 1 mol of glutaric anhydride to give N-(4-carboxybutyroyl) chitosans at DS of 0.10, 0.25, 0.48 and 0.53, respectively. The chemical structures and DS were characterized by ¹H and ¹³C NMR spectroscopy, which showed that the acylate reaction took place at the N-position of chitosan. The synthesized derivatives were more soluble than the native chitosan in water and in dilute aqueous acetic acid and sodium hydroxide solutions. The antimicrobial activity was in vitro investigated against the most economic plant pathogenic bacteria of Agrobacterium tumefaciens and Erwinia carotovora and fungi of Botrytis cinerea, Pythium debaryanum and Rhizoctonia solani. The antimicrobial activity of N-(4-carboxybutyroyl) chitosans was strengthened than the un-modified chitosan with the increase of the DS. A compound of DS 0.53 was the most active one with minimum inhibitory concentration (MIC) of 725 and 800 mg/L against E. carotovora and A. tumefaciens, respectively and also in mycelial growth inhibiation against B. cinerea (EC₅₀ = 899 mg/L), P. debaryanum (EC₅₀ = 467 mg/L) and R. solani (EC₅₀ = 1413 mg/L).     

Synthesis and antimicrobial activity of the Schiff base from chitosan and citral

Chitosan, a biocompatible, biodegradable, non-toxic polymer, is prepared from chitin, which is the second most naturally occurring biopolymer after cellulose. The Schiff base of chitosan was synthesized by the reaction of chitosan with citral working under high-intensity ultrasound. The effect of the molar ratio of chitosan to citral, reaction time, and temperature on the yield has been investigated. The optimal conditions were a temperature of 50 °C, a molar ratio of chitosan to citral of 1:6, and a reaction time of 10 h. The maximum yield achieved was 86.4% under optimum conditions. The structure of the Schiff base was characterized by FTIR spectroscopy, elemental analysis, and X-ray diffraction studies. The strong peaks at 1648.3 and 1610.6 cm⁻¹ are due to CN and CC stretching vibrations. The results confirmed that amino groups on chitosan reacted with citral to form the Schiff base. The antimicrobial activities of chitosan and Schiff base of chitosan were investigated against Escherichia coil, Staphylococcus aureus, and Aspergillus niger. The results indicate that the antimicrobial activity of the Schiff base increases with an increase in the concentration. It was also found that the antimicrobial activity of the Schiff base was stronger than that of chitosan.     

Quaternization of N-aryl chitosan derivatives: synthesis, characterization, and antibacterial activity

Chemical modification of chitosan by introducing quaternary ammonium moieties into the polymer backbone renders excellent antimicrobial activity to the adducts. In the present study, we have synthesized 17 derivatives of chitosan consisting of a variety of N-aryl substituents bearing either electron-donating or electron-withdrawing groups. Selective N-arylation of chitosan was performed via Schiff bases formed by the reaction between the 2-amino groups of the glucosamine residue of chitosan with aromatic aldehydes under acidic conditions, followed by reduction of the Schiff base intermediates with sodium cyanoborohydride. Each of the derivatives was further quaternized using N-(3-chloro-2-hydroxypropyl)trimethylammonium chloride (Quat-188) as the quaternizing agent that reacted with either the primary amino or hydroxyl groups of the glucosamine residue of chitosan. The resulting quaternized materials were water soluble at neutral pH. Minimum inhibitory concentration (MIC) antimicrobial studies of these materials were carried out on Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria in order to explore the impact of the extent of N-substitution (ES) on their biological activities. At ES less than 10%, the presence of the hydrophobic substituent, such as benzyl and thiophenylmethyl, yielded derivatives with lower MIC values than chitosan Quat-188. Derivatives with higher ES exhibited reduced antibacterial activity due to low quaternary ammonium moiety content. At the same degree of quaternization, all quaternized N-aryl chitosan derivatives bearing either electron-donating or electron-withdrawing substituents did not contribute antibacterial activity relative to chitosan Quat-188. Neither the functional group nor its orientation impacted the MIC values significantly.     

Upgrading the preparation of high-quality chitosan from Procambarus clarkii wastes over the traditional isolation of shrimp chitosan

Crustacean waste is one of the most severe issues, posing significant environmental and health risks. This study aims to improve managing marine waste by isolating chitosan from Procambarus clarkii by devising a new methodology, incorporating technical steps, e.g., washing, decolorization and deacetylation under a reflexive condenser and dialysis purification. A comparison was made between the prepared P. clarkii chitosan and four types of shrimp chitosans: commercial, high, low, and nano. The obtained chitosan has a low molecular weight and viscosity compared to the commercial shrimp chitosan used in various applications. P. clarkii chitosan was prepared in high quality from a cheap source, as its color and quality were better than those of the commercial shrimp chitosan. The new methodology has successfully extracted chitosan from P. clarkii in a good quality and high purity, achieving 89% deacetylation, high solubility, high purity, and medium molecular weight. Analysis of the different chitosan samples with Fourier transform infrared spectroscopy (FTIR), atomic force microscopy, Raman spectrum referred indicated high similarity between the chitosan different types, regardless of its source. The 3D image of P. clarkii showed the distance between the highest and most profound points of extracted chitosan is 728.94 nm, revealing homogeneous, smooth surfaces, apparently free of pores and cracks. FTIR and Raman spectrum of P. clarkii indicated various functional groups, e.g., alcohol, amines, amides, and phenols. These active groups are responsible for about 60% of the antioxidant activity of that product. Evaluating the quality traits indicated the excellence of the chitosan prepared from P. clarkii, especially in color, viscosity, and antioxidant activity, nominating it for different food applications.     

Antibacterial Activity of Alkylated and Acylated Derivatives of Low–Molecular Weight Chitosan

A number of alkylated (quaternized) and acylated derivatives of low–molecular weight chitosan were obtained. The structure and composition of the compounds were confirmed by the results of IR and PMR spectroscopy, as well as conductometric titration. The effect of the acyl substituent and the degree of substitution of N-(2-hydroxy-3-trimethylammonium) propyl fragment appended to amino groups of the C₂ atom of polymer chains on antibacterial activity against typical representatives of gram-positive and gramnegative microorganisms (Staphylococcus epidermidis and Escherichia coli) was studied. The highest activity was in the case of N-[(2-hydroxy-3-trimethylammonium)propyl]chitosan chloride (HTCC) with the maximal substitution (98%). The minimal inhibitory concentration of the derivative was 0.48 μg/mL and 3.90 μg/mL for S. epidermis and E. coli, respectively.     

The contribution of acidulant to the antibacterial activity of acid soluble α- and β-chitosan solutions and their films

This study evaluated individual contributions of dissolving acids (acetic acid, lactic acid, and hydrochloric acid) or acid solubilized chitosan to the antibacterial activity against Listeria innocua and Escherichia coli as solutions and dried films. Solutions containing chitosan showed significantly (P?<?0.05) different inhibitory activity (measured as percentage of inhibition (PI), in percent) against L. innocua and E. coli, compared to equivalent acid solutions. This increase was calculated as additional inhibition (AI, in percent), which could be as high as 65 % in solutions containing 300–320 kDa chitosan depending on the acid type, bacterial species, and the chitosan form (α or β). Solutions containing 4–5 kDa chitosan had lower AI and showed much greater variability among the different chitosan forms, acid types, and bacterial species. Higher molecular weight (Mw) chitosan also showed significantly higher levels of adsorption to bacterial cells than that of lower Mw samples, suggesting that the observed increase in inhibition was the result of surface phenomena. The contribution of acids to the antibacterial activity of chitosan films was assessed by comparing non-rinsed and rinsed films (rinsed in the appropriate broth to remove residual acids and active fragments formed on the dried film). Rinsing β-chitosan films has reduced PI by as much as 28 % compared with non-rinsed films, indicating that part of the antibacterial activity of chitosan films is due to the presence of soluble acid compounds and/or other active fragments. Overall, both acidulant and chitosan were found to contribute to the antibacterial activity of acid solubilized α- and β-chitosan, with the exact antibacterial activity of chitosan varying based on the solution and film properties, suggesting a complex interaction.     

Callus and cell suspension culture of <Emphasis Type="Italic">Viola odorata</Emphasis> as in vitro production platforms of known and novel cyclotides

Callus from Opuntia streptacantha (cv. Tuna loca), Opuntia megacantha (cv. Rubí reina), and Opuntia ficus-indica (cv. Rojo vigor) were exposed to jasmonic acid (JA) and abiotic stress (drought and UV light) to improve the metabolite production. The callus growth curves, phenolic acids and flavonoids content, antioxidant activity and phenylalanine ammonia lyase (PAL) activity were analyzed under normal and stress conditions. In O. streptacantha callus, the phenolics concentration increased 1.6 to 3 times times in presence of 5% PEG or after irradiation with UV light for 240 min, respectively, while flavonoids triplicate with UV light. A significant increase in antioxidant activity was observed in calli from the three Opuntia species in media with 50 µM JA. The relationships between metabolites/PAL activity, and metabolites/antioxidant activity were analyzed using a surface response methodology. Results showed that PAL activity, induced with PEG and UV, correlated with flavonoids content in O. megacantha and O. ficus-indica calli; PAL activity was related to both flavonoids and phenolics compounds in O. ficus-indica and O. megacantha calli exposed to JA, but only to flavonoids in O. streptacantha callus. In general, the JA stimulated simultaneously the metabolic pathways for phenolics and flavonoids synthesis, while abiotic stress induced mainly flavonoids route. As the stressed Opuntia calli exhibited as high antioxidant activity as cladodes, they are a promising system for research on antioxidant biosynthesis and/or to identify new compounds with antioxidant properties.     

Synthesis, characterization, and antifungal activity of novel quaternary chitosan derivatives

Three novel quaternary chitosan derivatives were successfully synthesized by reaction of chloracetyl chitosan (CACS) with pyridine (PACS), 4-(5-chloro-2-hydroxybenzylideneamino)-pyridine (CHPACS), and 4-(5-bromo-2-hydroxybenzylideneamino)-pyridine (BHPACS). The chemical structure of the prepared chitosan derivatives was confirmed by Fourier transform infrared (FT-IR) and ¹³C nuclear magnetic resonance (¹³C NMR) and their antifungal activity against Cladosporium cucumerinum, Monilinia fructicola, Colletotrichum lagenarium, and Fusarium oxysporum was assessed. Comparing with the antifungal activity of chitosan, CACS, and PACS, CHPACS and BHPACS exhibited obviously better inhibitory effects, which should be related to the synergistic reaction of chitosan itself with the grafted 2-[4-(5-chloro-2-hydroxybenzylideneamino)-pyridyl]acetyl and 2-[4-(5-bromo-2-hydroxybenzylideneamino)-pyridyl]acetyl.     

Preparation and characterization of chitosan encapsulated Sargassum sp. biosorbent for nickel ions sorption

A new biosorbent - Sargassum sp. encapsulated with epichlorohydrin (ECH) cross-linked chitosan (CS) was investigated for nickel ions removal. The prepared biosorbent with Sargassum sp. to cross-linked chitosan of 3 (weight ratio) had the highest sorption capacity. The biosorption kinetics can be well fitted by the diffusion-controlled model. The organic leaching of CS was 77-88% less than that of algae at different pH. The biosorption capacity of nickel on CS was much higher than that of cross-linked chitosan (CLC) bead and lower than that of raw algae due to encapsulation. In addition, the reusability of CS was further evaluated and confirmed through five adsorption-desorption cycles. Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) analysis demonstrated that the nickel ions sequestration mechanism included ion exchange and nickel complexation with the carboxyl, amino, alcoholic and ether groups in CS.     

Antimicrobial textile treated with chitosan from Aspergillus niger mycelial waste

The waste biomass of Aspergillus niger, following citric acid production, was used as a source for fungal chitosan extraction. The produced chitosan was characterized with deacetylation degree of 89.6%, a molecular weight of 25,000 dalton, 97% solubility in 1% acetic acid solution and comparable FT-IR spectra to standard shrimp chitosan. Fungal chitosan was applied as a cotton fabric finishing agent using pad-dry-cure method. The topographical structure of chitosan-treated fabrics (CTF) was much improved compared with control fabrics. CTF, after durability tests, exhibited a powerful antimicrobial activity against both E. coli and Candida albicans, the captured micrographs for E. coli cells contacted with CTF showed a complete lysis of cell walls with the prolonging contact time. The produced antimicrobial CTF could be proposed as a suitable material for many medical and hygienic applications.     

Biologically active fibers based on chitosan-coated lyocell fibers

The possibilities of obtaining biologically active cellulose–chitosan fibers were examined. An effective two-stage method was developed. The first stage involves the formation of dialdehyde cellulose by the potassium periodate oxidation of lyocell fibers, which is able to form Schiff’s base with chitosan. In the second stage, chitosan-coated lyocell fibers were prepared by subsequent treatment of oxidized lyocell fibers with a solution of chitosan in aqueous acetic acid. The impact of this two-stage protocol on the chemical and physical properties of lyocell fibers was evaluated by determining carbonyl group content, fineness and tensile strength of fibers, as well as chitosan content in the composite cellulose–chitosan fibers. Antibacterial activity of the chitosan-coated lyocell fibers against different pathogenens: Staphylococcus aureus and Escherichia coli, was confirmed in vitro experiments.     

Enhanced anti-topoisomerase II activity by mucoadhesive 4-CBS–chitosan/poly (lactic acid) nanoparticles

In this study, the biodegradable mucoadhesive 4-carboxybenzensulfonamide chitosan (4-CBS–chitosan)/poly (lactic acid) (PLA) nanoparticles were fabricated by the electrospray ionization technique for enhancing anti-topoisomerase II (Topo II) activity. The obtained (4-CBS–chitosan/PLA)-DOX nanoparticles were characterized using SEM, particle size analyzer. We emphasis on encapsulation efficiency, in vitro drug release behavior and also performed in vitro studies of Topo II inhibitory activity using gel electrophoresis. In addition, the cytotoxicity of the 4-CBS–chitosan/PLA nanoparticles using MTT assay was also studied. The mean particle size of spherical shaped (4-CBS–chitosan/PLA)-DOX is less than 300 nm. The DOX loaded 4-CBS–chitosan/PLA composite nanoparticles produced high entrapment efficiency of 85.8% and provided the prolonged release of DOX extended to 26 days and also still had strong Topo II inhibitory activity up to 77.4%. Overall, it was shown that 4-CBS–chitosan/PLA nanoparticles could be promising carriers for controlled delivery of anticancer drugs.