Antibacterial Activity Of Chitosan Research Articles

The Influence of Chitosan towards Antibacterial Properties in Natural Leather

The abundant hydroxyl groups (-OH) of vegetable tanned leather enhances the bacterial growth possibility. In this work, antibacterial vegetable tanned leather was developed taking advantage of chitosan antibacterial activity. Different chitosan utilization method was conducted, namely drum impregnation and spraying. Antibacterial testing was carried out using agar diffusion method to identify the effect of chitosan against Gram-positive bacteria (Staphylococcus aureus). The results showed that the use of 1% (w/v) chitosan by spraying method tends to be more effective in improving the antibacterial properties of vegetable tanned leather. While, the leather sample of drum impregnation at initial pH 4 has the lowest antibacterial activity among others. The results of FTIR analysis showed that there was no significant difference between control and chitosan modified tanned leather, confirming the similar functional groups between it.

Antibacterial Activity of Chitosan, Some Plant Seed Extracts and Oils Against Pathogenic Organisms Escherichia coli and Staphylococcus aureus

In this present study, various concentrations (0.5, 1, and 2%) of chitosan extracted through the chemical methods from the shells of crayfish (Astacus leptodactylus), pink shrimp (Parapenaeus longirostris), blue crab (Callinectes sapidus) shells, aqueous extracts of black cumin (Nigella sativa L), flaxseed (Linum usitatissimum), Chaste Tree (Vitex agnus-castus L.) and black cumin and flaxseed oil were tested in vitro for their antibacterial activities against tow pathogenic bacteria Escherichia coli and Staphylococcus aureus, using the disk diffusion method. On the other hand, were Eritromisin and florfenicol were used as a positive control. The negative control was Acetic Acid and cotton oil. Antimicrobial activity of chitosan is affected by different intrinsic and extrinsic factors. chitosan Source, molecular weight, deacetylation degree, viscosity, and solvent material, pH, ionic strength, metal ions, and bacteria cultures. In the present study, all four extracted chitosans were showed different antimicrobial effects on two different types of bacteria, while there are not any antibacterial effect of aqueous extracts and oils of the three plants seeds that used in this study.

Green synthesis, characterization and evaluation of catalytic and antibacterial activities of chitosan, glycol chitosan and poly(γ-glutamic acid) capped gold nanoparticles

Gold nanoparticles capped with chitosan (CH-NGs), glycol chitosan (GC-NGs) and poly(γ-glutamic acid) (PA-NGs) were synthesized separately, characterized and evaluated for catalytic and antibacterial activities. Surface Plasmon resonance peak at 520–530 nm confirmed the formation of NGs, while FTIR spectra revealed the involvement of hydroxyl, amine and amide groups in biopolymers on NGs formation and coating. Particle size, zeta potential and surface coating were respectively 21.7 nm, +50.2 mV and 20% for CH-NGs, 5.6 nm, +46.5 mV and 43.5% for GC-NGs and 7.4 nm, −37.3 mV and 34.5% for PA-NGs. Compared to citrate-capped NGs (CT-NGs), biopolymer-capped NGs exhibited high catalytic activity in a 4-nitrophenol reduction model with the pseudo first-order catalytic rate for PA-NGs being 4–6 fold higher than CH-NGs and GC-NGs. No significant antibacterial effect was shown for CT-NGs. However, PA-NGs was superior to gentamycin in inhibiting Salmonella enterica and Escherichia coli-O157:H7, while CH-NGs and GC-NGs showed the highest antibacterial effect against Listeria monocytogenes, followed by Salmonella enterica, Escherichia coli-O157:H7, methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus aureus. TEM images showed that GC-NGs were attached on MRSA surface to alter cell permeability, block nutrient flow and disrupt cell membrane, whereas PA-NGs penetrated into Salmonella enterica to generate cavities, plasmolysis and disintegration.

Extraction, Characterization, and Antimicrobial Activity of Chitosan from Horse Mussel Modiolus modiolus.

Chitin and chitosan have been proved to have enormous applications in biomedical, pharmaceutical, and industrial fields. The horse mussel, Modiolus modiolus, a refuse of the fishery industries at Thondi, is a reserve of rich chitin. The aim of this work is to extract chitosan from the horse mussel and its further characterization using Fourier transform infrared spectroscopy (FTIR), micro-Raman spectroscopy, X-ray diffraction (XRD), and elemental analysis. The result of FTIR studies revealed different functional groups of organic compounds such as out-of-plane bending (564 cm–1), C–O–C stretching (711 cm–1), and CH2 stretching (1174 cm–1) in chitosan. The degree of acetylation of the extracted chitosan was observed to be 57.43%, which makes it suitable as a biopolymer for biomedical applications. Prominent peaks observed with micro-Raman studies were at 484 cm–1 (14,264 counts/s), 2138 cm–1 (45,061 counts/s), and 2447 cm–1 (45,636 counts/s). XRD studies showed the crystalline nature of the polymer, and the maximum peak was observed at 20.04°. Elemental analysis showed a considerable decrease in the percentage of nitrogen and carbon upon the conversion of chitin to chitosan, while chitosan had a higher percentage of hydrogen and sulfur. The antibacterial activities of chitosan from the horse mussel were found to be efficient at a 200 μg/mL concentration against all the bacterial strains tested with a comparatively higher antibacterial activity against Escherichia coli (9 mm) and Bacillus subtilis (8 mm).

ANTIBACTERIAL EFFECT OF 0.2% CHLORHEXIDINE AND 1% CHITOSAN MOUTHWASH ON BACTERIA DURING ORTHODONTIC MINISCREW USE

Objective: Inflammation is one of the most common complications observed when using orthodontic miniscrews. Chlorhexidine mouthwash can beused to prevent and reduce the degree of inflammation, but long-term use of this solution may lead to some side effects. This study sought to evaluatethe peri-miniscrew antibacterial effect of 1% chitosan, a biomaterial with antibacterial properties, relative to 0.2% chlorhexidine mouthwash.Methods: A randomized, double-blind clinical trial was conducted at the Dental Teaching Hospital and Oral Biology Research Laboratory at theUniversity of Indonesia from February to June 2019. Thirty subjects (25 females and five males) were randomly assigned to rinse with 1% chitosan(n=10), 0.2% chlorhexidine digluconate (n=10), and Aquadest (n=10) in addition to their usual oral hygiene procedure for 4 days. Peri-miniscrewclinical inflammation signs were recorded and peri-miniscrew plaque collected before and after 4 days of rinsing. The total bacterial and red-complexbacteria count in plaque samples were evaluated by a real-time polymerase chain reaction.Results: Chitosan and chlorhexidine showed antibacterial activity, reducing total bacterial count around orthodontic miniscrews (p<0.05). Theantibacterial activity of chitosan on total bacteria was not significantly different from that of chlorhexidine (p≥0.05). Regarding the antibacterialactivity of chitosan on red-complex bacteria, the best result seen was a 58% bacteria count reduction in Tannerella denticola.Conclusion: Chitosan has potential antibacterial activity and could be used in mouthwash to maintain peri-miniscrew hygiene.

Quercetin-grafted chitosan prepared by free radical grafting: characterization and evaluation of antioxidant and antibacterial properties.

Chitosan (CS) is considered a versatile biopolymer with promising applications. However, it is not a good chain-breaking antioxidant due to the lack of H-atom donors. In this work, CS was combined with quercetin (Q), a natural antioxidant, via a free radical-mediated procedure to strengthen the antioxidant capacity. The successful formation of Q-grafted CS (Q-CS) was confirmed by ultraviolet-visible absorbance and Fourier transform infrared spectroscopy. After combination, the obtained Q-CS had a phenolic content of 13.9mg QE/g Q-CS and showed a lower crystallinity and thermal stability than the native CS. The 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), superoxide, and hydroxyl radical scavenging activities of Q-CS were higher than those of CS, illustrating that grafting with Q is an available way to improve the antioxidant capacity of CS. In addition, Q-CS showed higher minimal inhibitory concentrations against tested bacteria than CS, suggesting that combining with Q has a negative effect on the antibacterial activity of CS. Our results indicate that Q-CS may have great potential for applications in the fields of food and healthcare.

Evaluation of antibacterial activity of chitosan against different bacterial strains

The present study is related to new green and low cost technical method for wastewater treatment using chitosan as natural material. Chitosan was prepared from chitin of the seafood’s shell (Procambrus clarkia). Preparation of chitosan was carried out by a chemical process involving demineralization, deproteinization and deacetylation. Chitosan is largely known for its activity against a wide range of microorganisms. Antibacterial effect of different doses of chitosan (0.09, 0.2, 0.4, 0.6 and 0.8 g) on Escherichia coli (E. coli) bacteria in the secondary treated wastewater samples was studied. The secondary treated wastewater was collected from Zenein wastewater treatment plant. Also the effectiveness of chitosan on Enterococcus faecalis, Bacillus subtillus, Staphylococcu saureus (gram +ve bacteria), Escherichia coli, Enterobacter aerogenes (gram –ve) was evaluated by the reduction in total bacterial count of each strain in synthetic media. The study was extended to measure the antibacterial activity (inhibition zone) of chitosan on E. coli by the poured plate method. The results indicated that the optimum conditions at which 99.98% removal for all types of bacteria were 0.6 g chitosan, contact time 30 min and shaking 250 rpm. According to the obtained results, the most acceptable antimicrobial mechanism is found to include the presence of charged groups in the polymer backbone and their ionic interactions with bacterial wall constituents. It could be concluded that chitosan could be used for disinfection of the secondary treated wastewater.

Proteomic Analyses Reveal New Insights on the Antimicrobial Mechanisms of Chitosan Biopolymers and Their Nanosized Particles against Escherichia coli.

The well-known antimicrobial effects of chitosan (CS) polymers make them a promising adjuvant in enhancing antibiotic effectiveness against human pathogens. However, molecular CS antimicrobial mechanisms remain unclear, despite the insights presented in the literature. Thus, the aim of the present study was to depict the molecular effects implicated in the interaction of low or medium molecular mass CS polymers and their nanoparticle-counterparts against Escherichia coli. The differential E. coli proteomes sensitized to either CS polymers or nanoparticles were investigated by nano liquid chromatography–mass spectrometry (micro-LC-MS/MS). A total of 127 proteins differentially expressed in CS-sensitized bacteria were predominantly involved in (i) structural functions associated to the stability of outer membrane, (ii) increment of protein biosynthesis due to high abundance of ribosomal proteins and (iii) activation of biosynthesis of amino acid and purine metabolism pathways. Antibacterial activity of CS polymers/nanoparticles seems to be triggered by the outer bacterial membrane disassembly, leading to increased protein biosynthesis by diverting the metabolic flux to amino acid and purine nucleotides supply. Understanding CS-antibacterial molecular effects can be valuable to optimize the use of CS-based nanomaterials in food decontamination, and may represent a breakthrough on CS nanocapsules-drug delivery devices for novel antibiotics, as the chitosan-disassembly of bacteria cell membranes can potentialize antibiotic effects.

Preparation of PVA/Chitosan samples by electrospinning and film casting methods and evaluating the effect of surface morphology on their antibacterial behavior

Chitosan due to outstanding properties including biocompatibility, biodegradability, nontoxicity and antibacterial activity has received considerable attention in different fields of biomedical engineering. To study the effect of morphology and topology on antibacterial activity of chitosan, two samples of PVA/Chitosan blend with the same concentration and volume ratio were prepared using electrospinning and film casting methods. To improve the electrospinability of chitosan, it was hydrolyzed by 50% V NaOH solution (95 °C for 48 h.) and PVA was used as an auxiliary polymer for electrospinning. The best electrospinning parameters for producing beadless structure were determined at a voltage of 21 kV and distance of 15 cm. Different physical and chemical characterizations of produced samples were performed using scanning electron microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), viscosimetry, Atomic Force Microscopy (AFM) and antibacterial assay by two different bacterium strains including Escherichia coli (E.coli) as the gram-negative and Staphylococcus aureus (S.aureus) as the gram-positive bacteria. Antibacterial assays revealed higher sensitivity of E.coli in comparison with S.aureus in the two samples. Also, it revealed that nanotopography of surface wielded influence on the antibacterial activity of samples.

In vitro antibacterial activity of ciprofloxacin loaded chitosan microparticles and their effects on human lung epithelial cells.

Chitosan (CS), due to its inherent mucoadhesive property and biofilm penetration ability, can be considered as very potent vehicle for local drug delivery to the lungs. This study reports on the preparation and in vitro antibacterial activity and cytotoxicity determination of ciprofloxacin loaded chitosan (Cipro-CS) microparticles with size in the range of 0.1-1 µm, which may provide advantages of lower nanotoxicity and lower local clearance. Cipro-CS microparticles were prepared by ionic gelation method and their size, zeta potential and drug release pattern determined. The antibacterial activities of CS and Cipro-CS microparticles against pneumonia causing agents, namely Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus, were evaluated by determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The biocompatibility of the microparticles was tested in the human lung epithelial cell (BEAS-2B) culture, and microparticle association with the bacteria and epithelial cells was evaluated by transmission electron microscopy. Only the Cipro-CS microparticles, but not the CS microparticles, inhibited bacterial growth at concentrations not significantly cytotoxic to BEAS-2B cells. The Cipro-CS microparticles were able to damage the cell wall and membrane of the bacteria, and the ones ≤200 nm in size were internalized by both the BEAS-2B cells and the microorganisms.

Antibacterial activity of chitosan and its combination with other irrigants on Enterococcus faecalis: An in vitro study

Objective: The aim of the in vitro study was to compare the antibacterial efficacy of sodium hypochlorite (NaOCl), chlorhexidine (CHX), chitosan and their combinations in vitro. Materials and Methods: A total of 60 extracted single-rooted teeth were selected and used for the study. After the access cavity preparation and working length determination, the apical foramina of the samples were sealed with epoxy resin to prevent bacterial leakage, and the teeth were mounted in stone blocks. Biomechanical preparation was done using crown-down technique up to master apical file size of #50. Enterococcus faecalis (ATCC 29212) was used to contaminate the root canals. After incubation, samples were divided into six groups according to the solutions used for irrigation, that is, CHX, NaOCl, chitosan, alternating solution of chitosan and hypochlorite, alternating solution of chitosan and CHX, and saline. Antibacterial efficacy was assessed by obtaining the samples from root canal before and after the irrigation using paper points, culturing them on blood agar plates, and measuring the number of colony-forming units (CFUs) formed. Results: All the statistical analysis was done using SPSS version 16. P 0.001). Maximum antibacterial activity was seen when chitosan was used alternatively with CHX and NaOCl. Independently, hypochlorite showed maximum antibacterial activity followed by CHX and chitosan which showed almost similar antibacterial activity. Conclusion: According to this study, there is synergistic antibacterial activity when chitosan is used alternatively with 2% CHX or 5% NaOCl.

Evaluation the biological activities of chitosan and O-carboxymethyl chitosan extracted from crab shell waste

The main objective of this study is to prepare chitosan and O-carboxymethyl chitosan and evaluate their biological activities in vitro. In this study, twenty crab shells were collected from locally fish restaurant in the city of Tanta, Egypt. Chitosan has been produced from crab waste by chemical method then modified by introducing carboxymethyl group into its back bone. The antibacterial activity of chitosan and O-carboxymethyl chitosan was tested against multidrug-resistant bacteria by cut-plug method. It was found that the antibacterial activity of modified chitosan was better than the native one. On the other hand, the cytotoxicity of chitosan and O-carboxymethyl chitosan was tested on liver carcinoma cell line HEPG-2 and normal human fibroblast cells (WISH 38). They recorded cytotoxic activities on liver carcinoma cell line, while their toxicities on normal human fibroblast cells were negligible. Finally, their antibacterial activity was evaluated in vivo; the results showed that they were highly active and safe in the treatment of wound infection.

Biological Activity of Native and Low Molecular Weight Chitosan obtained by Steam Explosion Process.

Low molecular weight chitosan (LWCS) was interestingly used because of it's solubility and has good functional properties like antioxidant and antibacterial activity. This study aimed to evaluate antioxidant and antibacterial activity of chitosan and low molecular weight chitosan. Low molecular weight chitosan was obtained by physical and chemical hydrolysis using steam explosion process with steam pressure at 6 bar, temperature at 160°C and concentration of phosphotungstic acid at 0.1% w/v. The antioxidant activity was confirmed by radical DPPH scavenging activity, chelating metal ion value, inhibitory lipid peroxidation and antibacterial activity was confirmed by diffusion methods. LWCS had antioxidant activity higher than native chitosan on radical scavenging, chelating ion value and inhibition of lipid peroxidation. LWCS had higher inhibitory effect as antibacterial than native chitosan against tested bacteria, there were Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Streptococcus aureus and Bacillus subtilis. It was concluded that LWCS had more powerful antioxidant and antibacterial activity than native chitosan.

Evaluation of physico-chemical properties and antimicrobial synergic effect of ceftazidime-modified chitosan

The high prevalence of infections caused by antibiotic-resistant bacteria has stimulated the development of new therapeutic strategies. Polymeric materials have aroused the interest of many researchers because of their large field of applications. This work aimed to evaluate the synergistic antimicrobial effect of chitosan in association with ceftazidime as well as possible chemical interactions from this combination by FTIR, XRD and TG/DTG curves. Through these analyses, it was possible to conclude that the proposed method was efficient to incorporate the drug with no changes in the fundamental structure of chitosan. In addition, the developed carrier was responsible for increasing the thermal and hydrolytic stability of the drug. The antibacterial activity of chitosan and ceftazidime-modified chitosan was evaluated against Staphylococcus aureus 25,923 and Escherichia coli 25,922 strains, revealing a possible time-dependent drug release.

Toxicity tests, antioxidant activity, and antimicrobial activity of chitosan

Chitosan is a naturally occurring cationic biopolymer, obtained by alkaline deacetylation of chitin. This research aims to investigate the toxicity, antioxidant activity and antibacterial activity of chitosan from shrimp chitin. In this study, chitin extracted from shrimp waste material. Chitin is then deacetylation with 60% NaOH so that chitosan produced. Degrees of deacetylation, molecular weight, toxicity test, antioxidant activity and antimicrobial activity of chitosan then evaluated. Toxicity test using Brine Shrimp Lethality Test. The antioxidant analysis was performed using DPPH method (2, 2-diphenyl-1-picrylhydrazyl) and FTC method (ferric thiocyanate) in which the radical formed will reduce Ferro to Ferri resulting in a complex with thiocyanate. To determine the antibacterial activity of Staphylococcus aureus, antifungal in Candida albicans and Aspergillus niger by measuring antimicrobial effects and minimum inhibitory concentrations (MIC). Based on the result of research, the value of degrees of deacetylation, molecular weight, and LC50 values of chitosan synthesis was 94,32, 1052.93 g/mol and 1364.41 ppm, respectively. In general, the antioxidative activities increased as the concentration of chitosan increased. MIC value of chitosan against S. aureus, C. albicans, and A. niger was 10 ppm, 15.6 ppm, and 5 ppm, respectively.

Antibacterial activity of chitosan against Burkholderia pseudomallei.

The ability of Burkholderia pseudomallei to persist and survive in the environment is a health problem worldwide. Therefore, the antibacterial activities of chitosan against four environmental isolates of B. pseudomallei from soil in Khon Kaen, Thailand, were investigated. Antibacterial activities were assessed by a plate count technique after treatment with 0.2, 0.5, 1, 2 or 5 mg ml−1 chitosan for 0, 24 and 48 hr. Chitosan at 5 mg ml−1 completely killed all four B. pseudomallei isolates within 24 hr, whilst 2 mg ml−1 chitosan lowered the viability of B. pseudomallei by 20% within the same time span. Chitosan may act by disruption of the cell membrane, releasing intracellular components that can be detected spectrophotometrically at 260 and 280 nm. Transmission electron microscopy inspection of chitosan‐treated B. pseudomallei revealed damage to the bacterial membranes. This study demonstrated the effective antibacterial activity by chitosan against B. pseudomallei. Chitosan causes disruption of the bacterial cell membrane, release of intracellular constituents and cell death. This study revealed the inhibitory potential of chitosan for mitigating B. pseudomallei occurrences.

Microwave‐assisted degradation of chitosan with hydrogen peroxide treatment using Box‐Behnken design for enhanced antibacterial activity

SummaryLow molecular mass (MM) chitosan with high degree of deacetylation (DDA) has excellent bioactivity including antioxidant, antibacterial and encapsulation properties. In this work, to reduce the MM of chitosan, microwave‐assisted heating treatment (MAHT) conditions were investigated using three factors at three levels Box‐Behnken design (BBD). Microwave heating (MH) time, H2O2 concentration and solid‐to‐liquid ratio significantly affected the DDA and MM of chitosan. The antibacterial activities of chitosan before and after degradation were investigated based on minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The results showed that a second‐order polynomial equation fitted the observed values using multiple regression analysis and had a high coefficient of determination (R2 = 0.9591 and 0.9161 for the DDA and MM of chitosan, respectively). An optimisation study was performed using Derringer's desirability function methodology, and the optimal conditions were 80‐s MH time, 1.5% H2O2 concentration and 1:40 solid‐to‐liquid ratio. The MIC and MBC of chitosan before and after degradation against Escherichia coli and Salmonella typhimurium were 0.031 and 0.063 mg mL−1, and 0.25 and 0.125 mg mL−1, respectively. The optimised DDA and MM of chitosan were 90.58 ± 2.04% and 124.25 ± 14.36 kDa, respectively, which significantly reduces the use of oxidant reagent.

Antimicrobial activity of chitosan and a chitosan oligomer against bacterial pathogens of warmwater fish.

The antibacterial activities of chitosan (CS) and its derivative chitosan oligosaccharide lactate (COL) were evaluated against Aeromonas hydrophila, Edwardsiella ictaluri and Flavobacterium columnare, three highly pathogenic bacteria of warmwater finfish. The magnitude and mode of antimicrobial action on Gram-negative bacterial pathogens was investigated with an emphasis on examining the inhibition of bacterial growth and the weakening of barrier functions. Both CS and COL exhibited antibacterial activity against all three bacteria tested and their activity was dose-dependent. CS and COL completely inhibited growth of A. hydrophila at 0·8% and E. ictaluri and F. columnare at 0·4% or higher concentrations. COL was more effective in killing or inhibiting the growth of all bacteria tested. CS and COL molecules have the ability to interact with bacterial surfaces via adsorption. This was confirmed by initial decreases in the conductivity of CS or COL treated bacterial cell solutions. A marked re-increase in conductivity from 18 to 48h was documented, which was due to the leakage of cellular ions into the solution through damaged bacterial cell membranes. Both CS and COL exhibited antibacterial activity against all three bacterial species through a sequential process beginning with adsorption to bacterial surfaces culminating in the leakage of intracellular constituents and cell death. These findings indicate that CS-based strategies are promising candidates for exploration as alternatives to antibiotics for mitigating disease outbreaks in cultured fish.

Preparation and antimicrobial activity of sulfopropyl chitosan in an ionic liquid aqueous solution

ABSTRACTTo improve the solubility and antibacterial activity of chitosan and expand its applications, we synthesized sulfopropyl chitosan (SP‐CS) with various degrees of substitution (DSs) under mild and green reaction conditions in the aqueous solution of an ionic liquid by a green process. The chemical structures of the polymers were verified by Fourier transform infrared spectroscopy and 1H‐NMR, and the thermal stability was studied by thermogravimetric analysis. After modification, the water solubility of chitosan was improved significantly, and SP‐CS showed excellent solubility in water at neutral pH. The antibacterial activities of the SP‐CSs with various DSs were systematically studied for the first time by the Oxford cup method and optical density method. The results suggest that the antimicrobial properties of SP‐CS were enhanced by the introduction of sulfopropyl and increased with increasing DS. The application of chitosan could be expanded, and SP‐CS has the potential to be used as a water‐soluble antimicrobial. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44989.

Application of Chitosan as Antibacterial for Pangasius Fillet at Low Temperature Storage

<p>Abstract<br />This research were to obtain the optimal concentration of chitosan as an antibacterial material wich had the longest of storage period of pangasius fillet at low temperature storage (5-10oC). The method used is an experimental method with a completely randomized design, four treatments and three replications. Pangasius fillet was soaked with chitosan 0%, 1%, 2% and 3% for 3 minutes, then packed with styrofoam and plastic wrap and stored at low teperature. The observation were made on day 1st, 3rd, 5th, 6th ,7th, 9th,10th, 11th and 12th. The parameters observed total bacterial colonies, the degree of acidity (pH), weight loss, and antibacterial activity of chitosan using disc diffusion methods. The conclusion of research was that the 2% chitosan is optimal concentration for pangasius fillet storage at a low temperature until day 11th, with a total 6.7 X105 cfu/g of bacterial colonies, pH 6.67 and total 6,78 % of weight loss.Chitosan also has a higher antibacterial capability against Escherichia coli (Gram negative bacteria) than Staphylococcus aureus and Bacillus subtilis (Gram positive bacteria).</p>