scholarly journals Efektivitas antibakteri gel chitosan dengan berat molekul berbeda terhadap jumlah koloni bakteri Streptococcus mutans pada permukaan email sekitar braket ortodonti Antibacterial effectiveness of chitosan gel with different molecular weights on the number of Streptococcus mutans colonies in the enamel surface around orthodontic bracket

2021 ◽  
Vol 33 (3) ◽  
pp. 204
Author(s):  
Della Noor Insany ◽  
Haru Setyo Anggani ◽  
Widya Kusumadewi
Keyword(s):  
Molecular Weight ◽  
Streptococcus Mutans ◽  
Enamel Surface ◽  
Orthodontic Brackets ◽  
Chlorhexidine Digluconate ◽  
Orthodontic Bracket ◽  
Molecular Weights ◽  
Significant Difference ◽  
Chitosan Gel ◽  
One Way Anova

Pendahuluan: Chitosan merupakan bahan alami, bersifat antibakteri, dan dapat dibentuk menjadi gel sehingga berpotensi sebagai agen profilaksis terhadap Streptococcus mutans, penyebab demineralisasi email. Lesi white spot merupakan salah satu risiko penggunaan alat ortodonti cekat. Berat molekul merupakan salah satu faktor yang memengaruhi efektivitas antibakteri chitosan, namun hubungannya masih memberikan hasil yang inkonsisten. Penelitian ini bertujuan menganalisis perbedaan efektivitas gel chitosan dengan berat molekul berbeda terhadap jumlah koloni bakteri Streptococcus mutans pada permukaan email sekitar braket ortodonti. Metode: Penelitian ini menggunakan metode eksperimen laboratoy dengan menggunakan 24 sampel gigi dengan braket dioles gel chitosan A (50-80 kDa),  gel chitosan B (50-150 kDa), gel chitosan C (190-310 kDa), dan gel kontrol klorheksidin diglukonat 0,2% (CHX) masing-masing 6 sampel. Seluruh sampel diinkubasi dalam biakan Streptococcus mutans secara bertahap, 10 μl suspensi dari plak yang terbentuk pada sampel dibiakkan untuk memperoleh koloni pada biakan agar. Data dianalisis dengan uji one-way ANOVA dan Least Significant Difference (LSD).  Hasil: Jumlah koloni bakteri Streptococcus mutans setelah aplikasi gel chitosan A, B, C, dan gel klorheksidin diglukonat 0,2% (CHX) didapatkan sebesar 10,05x106 CFU/ml; 9,72x106 CFU/ml; 10,96x106 CFU/ml; dan 4,35x106 CFU/ml sehingga tidak terdapat perbedaan bermakna jumlah koloni bakteri Streptococcus mutans antara ketiga kelompok gel chitosan (p>0,05) dan terdapat perbedaan jumlah koloni bakteri Streptococcus mutans yang bermakna antara ketiga gel chitosan dengan gel kontrol (p<0,05). Simpulan: Efektivitas antibakteri gel chitosan dengan berat molekul berbeda terhadap jumlah koloni bakteri Streptococcus mutans pada permukaan email sekitar braket ortodonti adalah sama besar, namun lebih rendah daripada efektivitas antibakteri gel klorheksidin diglukonat 0,2% pada studi ini.Kata kunci: berat molekul; braket ortodontik; kitosan; email; Streptococcus mutans  ABSTRACTIntroduction: Chitosan is a natural ingredient, antibacterial, and can be formed into a gel so that it has the potential as a prophylactic agent against Streptococcus mutans, the cause of enamel demineralization. White spot lesions are one of the risks of using fixed orthodontic appliances. Molecular weight is one factor that affects the antibacterial effectiveness of chitosan, but the relationship still gives inconsistent results. This study aimed to analyze the differences in the effectiveness of chitosan gels with different molecular weights on the number of Streptococcus mutans bacteria colonies on the enamel surface around orthodontic brackets. Methods: This study used an experimental laboratory method using 24 dental samples with brackets smeared with chitosan A gel (50-80 kDa), chitosan B gel (50-150 kDa), chitosan C gel (190-310 kDa), and chlorhexidine control gel. digluconate 0.2% (CHX) each of 6 samples. All samples were incubated in Streptococcus mutans culture in stages, 10 l suspension of the plaque formed on the samples was cultured to obtain colonies on agar cultures. Data were analyzed by one-way ANOVA and Least Significant Difference (LSD). Results: The number of Streptococcus mutans colonies after application of chitosan gel A, B, C, and 0.2% chlorhexidine digluconate (CHX) gel was 10.05x106 CFU/ml; 9.72x106 CFU/ml; 10.96x106 CFU/ml; and 4.35x106 CFU/ml, so that there was no significant difference in the number of Streptococcus mutans colonies between the three chitosan gel groups (p>0.05) and there was a significant difference in the number of Streptococcus mutans bacteria colonies between the three chitosan gels and the control gel (p<0.05). Conclusions: The antibacterial effectiveness of chitosan gel with different molecular weights on the number of Streptococcus mutans bacterial colonies on the enamel surface around orthodontic brackets was simi-lar but lower than the antibacterial effectiveness of 0.2% chlorhexidine digluconate gel.Keywords: molecular weight; orthodontic bracket; chitosan; enamel; Streptococcus mutans

Effects of Molecular Weight of Chitosan on the Biodegradability and Thermal Properties of Polybutylene Succinate/Chitosan Composites

2018 ◽  
Vol 775 ◽  
pp. 26-31
Author(s):  
Sukantika Manatsittipan ◽  
Kamonthip Kuttiyawong ◽  
Kazuo Ito ◽  
Sunan Tiptipakorn
Keyword(s):  
Molecular Weight ◽  
Weight Loss ◽  
Thermal Properties ◽  
Water Absorption ◽  
Melting Temperature ◽  
Microbial Degradation ◽  
Decomposition Temperature ◽  
Molecular Weights ◽  
Significant Difference ◽  
Polybutylene Succinate

In this study, the biodegradability and thermal properties the composites of polybutylene succinate (PBS) and chitosan of different molecular weights (Mn = 104,105, and 106 Da) were prepared at chitosan contents of 0-10 wt%. After 10 days of microbial degradation, the results show that the amount of holes from degradation was increased with either decreasing Mn or increasing chitosan contents. However, the size of holes was increased with increasing Mn and chitosan contents. The results from Differential Scanning Calorimeter (DSC) present that the melting temperature (Tm) of PBS was decreased with increasing chitosan contents. Moreover, there was no significant difference between Tm of the composites with different Mn of chitosan. From the TGA thermograms, the decomposition temperature at 10% weight loss (Td10) was decreased with increasing chitosan contents. Moreover, the water absorption of PBS/chitosan composites was increased with increasing Mn and content of chitosan.

scholarly journals Effect of Two Different Mouth Rinses on S. mutans Counts in Subjects Undergoing Orthodontic Treatment – A Pilot Study

2020 ◽  
pp. 148-155
Author(s):  
S. Abirami ◽  
Ravindra Kumar Jain ◽  
A. S. Smiline Girija
Keyword(s):  
Streptococcus Mutans ◽  
Reference Group ◽  
T Test ◽  
Orthodontic Brackets ◽  
Plaque Index ◽  
Cervical Region ◽  
Paired Sample ◽  
Group I ◽  
Significant Difference ◽  
Group Ii

The study is thus aimed to assess and compare the efficacy of Herbostra oil pulling mouthwash with Chlorhexidine mouthwash in reducing plaque accumulation around orthodontic brackets. A total of 20 patients were considered in this study randomly assigned into Group I (experimental group - Herbostra oil pulling mouthwash) and Group II (reference group-0.2% Chlorhexidine mouthwash). The plaque index scores were recorded in each individual at baseline (pre) and after 3 weeks (post). Dental plaque samples were collected around the orthodontic brackets at the cervical region of maxillary upper molars and lower incisors by cotton swabbing method and evaluated for the presence of microflora. Paired sample t-test for Streptococcus mutans count showed that statistically significant difference only within the group II (p=0.000) (Chlorhexidine group) and there was no significant difference within the group I (p=0.103) (Herbostra group). Paired sample t-test for plaque index score shows statistically significant difference within the groups (0.000).Independent t test showed statistically significant difference in the levels of  Streptococcus mutans count after 3 weeks between the two groups (p=0.000) with the mean values of (2.230±0.5056), (1.080±0.3458) in group I and group II respectively. From this study we concluded that, even though there was a reduction in plaque scores and S. mutans count with Herbostra oil pulling mouthwash but it was not as effective as Chlorhexidine mouth rinse.

scholarly journals Scanning Electron Microscopy Analysis of Changes of Hydroxiapatite/Poly-L-Lactide with Different Molecular Weight of PLLAaAfter Intraperitoneal Implantation

2016 ◽  
Vol 66 (2) ◽  
pp. 234-244
Author(s):  
Ljubiša Đorđević ◽  
Stevo Najman ◽  
Perica Vasiljević ◽  
Miroslav Miljković ◽  
Nenad Ignjatović ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Molecular Weight ◽  
Scanning Electron Microscopy ◽  
Bone Tissue ◽  
Tissue Loss ◽  
Practical Applications ◽  
Molecular Weights ◽  
Significant Difference ◽  
Tissue Reactions ◽  
Scanning Electron

Abstract Implantation of a biomaterial is one of the important trends in solving the problem of bone tissue loss. Calcium hydroxiapatite (HAp), as the most representative bone component is a serious candidate for such implantations. The synthetic polymer poly-L-lactide (PLLA) in HAp/PLLA is often used as a polymeric material, with a role in the substitution of bone tissue collagen fibers. Fibers of PLLA may strengthen HAp and its good bioresorption provides space for tissue remodeling. Differences in porosity, microstructure, compressive consistency as well as bioresorbility of HAp/ PLLA may be achieved by using PLLA with different molecular weights. In this study HAp/PLLA composites with PLLA of different molecular weights (50,000; 160,000 and 430,000) were implanted in mouse peritoneum in order to examine the influence of the molecular weight of PLLA on morphology changes. Microstructural changes of biomaterial (HAp/PLLA) surface were analyzed one week, three weeks and four months after their implantation using Scanning Electron Microscopy. The results showed a significant difference in tissue reactions on the applied biocomposites, depending on their molecular weight. The most intense proliferation of cells was induced by HAp/PLLA 50,000 compared to HAp/PLLA 430,000 and HAp/PLLA 160,000. In the vicinity of HAp/PLLA 430,000 abundant erythrocytes were observed. The differences in biological reactions on the examined biocomposites are significant for their practical applications. HAp/PLLA composite biomaterials of different types and resorption rates require specific designing and programming to become suitable for particular purposes in an organism.

scholarly journals Glass Ionomer Cements can be used for Bonding Orthodontic Brackets After Cancer Radiation Treatment?

2018 ◽  
Vol 29 (2) ◽  
pp. 128-132 ◽  
Author(s):  
Gabriela Cristina Santin ◽  
Alexandra Mussolino de Queiroz ◽  
Regina Guenka Palma-Dibb ◽  
Harley Francisco de Oliveira ◽  
Paulo Nelson Filho ◽  
...  
Keyword(s):  
Bond Strength ◽  
Shear Bond Strength ◽  
Glass Ionomer Cement ◽  
Enamel Surface ◽  
Orthodontic Brackets ◽  
Glass Ionomer ◽  
Clinical Practices ◽  
Significant Difference ◽  
Resin Modified Glass Ionomer ◽  
Ionomer Cement

Abstract Patients undergoing radiotherapy treatment present more susceptibility to dental caries and the use of an orthodontic device increases this risk factor due to biofilm accumulation around the brackets. The objective of this study was to evaluate the shear bond strength to irradiated permanent teeth of orthodontic brackets bonded with conventional glass ionomer cement and resin-modified glass ionomer cement due to the fluoride release capacity of these materials. Ninety prepared human premolars were divided into 6 groups (n=15), according to the bonding material and use or not of radiation: CR: Transbond XT composite resin; RMGIC: Fuji Ortho LC conventional glass ionomer cement; GIC: Ketac Cem Easymix resin-modified glass ionomer cement. The groups were irradiated (I) or non-irradiated (NI) prior to bracket bonding. The specimens were subjected to a fractioned radiation dose of 2 Gy over 5 consecutive days for 6 weeks. After the radiotherapy, the brackets were bonded on the specimens with Transbond XT, Fuji Ortho LC and Ketac Cem Easymix. After 24 h, the specimens were subjected to shear bond strength test. The image of enamel surface (classified by Adhesive Remnant Index - ARI) was also evaluated and its frequency was checked among groups/subgroups. The shear bond strength variable was evaluated with ANOVA and Tukey’s post-hoc test. GIC group showed the lowest adhesion values among the groups (p<0.05). There was no statistically significant difference among non-irradiated and irradiated groups (p>0.05). As for the ARI, the CR-I group showed the highest material retention on enamel surface among the irradiated groups. RMGIC group showed the highest values for shear bond strength and presented ARI acceptable for clinical practices.

scholarly journals Comparison of Orthodontic Bracket Debonding Force and Bracket Failure Pattern on Different Teeth In Vivo by a Prototype Debonding Device

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Tamzid Ahmed ◽  
Norma Ab Rahman ◽  
Mohammad Khursheed Alam
Keyword(s):  
Failure Pattern ◽  
Point Scale ◽  
Orthodontic Bracket ◽  
Adhesive Remnant Index ◽  
Significant Difference ◽  
Different Types ◽  
Post Hoc ◽  
Bracket Failure ◽  
One Way Anova

Objective. To compare the orthodontic bracket debonding force and assess the bracket failure pattern clinically between different teeth by a validated prototype debonding device. Materials and Method. Thirteen (13) patients at the end of comprehensive fixed orthodontic treatment, awaiting for bracket removal, were selected from the list. A total of 260 brackets from the central incisor to the second premolar in both jaws were debonded by a single clinician using a validated prototype debonding device equipped with a force sensitive resistor (FSR). Mean bracket debonding forces were specified to ten (10) groups of teeth. Following debonding, Intraoral microphotographs of the teeth were taken by the same clinician to assess the bracket failure pattern using a 4-point scale of adhesive remnant index (ARI). Statistical analysis included one-way ANOVA with post hoc Tukey HSD and independent sample t -test to compare in vivo bracket debonding force, Cohen’s kappa ( κ ), and a nonparametric Kruskal-Wallis test for the reliability and the assessment of ARI scoring. Results. A significant difference ( p < 0.001 ) of mean debonding force was found between different types of teeth in vivo. Clinically, ARI scores were not significantly different ( p = 0.921 ) between different groups, but overall higher scores were predominant. Conclusion. Bracket debonding force should be measured on the same tooth from the same arch as the significant difference of mean debonding force exists between similar teeth of the upper and lower arches. The insignificant bracket failure pattern with higher ARI scores confirms less enamel damage irrespective of tooth types.

scholarly journals Pengaruh Ekstrak Kulit Jeruk Nipis (Citrus Aurantifolia Swingle) Konsentrasi 10% Terhadap Aktivitas Enzim Glukosiltransferase Streptococcus mutans

2013 ◽  
Vol 20 (2) ◽  
pp. 126
Author(s):  
Zenia Adindaputri U ◽  
Nunuk Purwanti ◽  
Ivan Arie Wahyudi
Keyword(s):  
Enzyme Activity ◽  
Streptococcus Mutans ◽  
High Performance ◽  
Positive Control ◽  
Chlorhexidine Gluconate ◽  
Citrus Aurantifolia ◽  
Significant Difference ◽  
Lime Peel ◽  
One Way Anova ◽  
Peel Extract

Streptococcus mutans merupakan bakteri yang berperan sebagai agen utama penyebab karies gigi, yang memiliki enzim glukosiltransferase (GTF). Enzim GTF akan mengubah sukrosa menjadi fruktosa dan glukan. Salah satu herbal tradisional yang dapat berperan sebagai antibakteri adalah kulit jeruk nipis (Citrus aurantifolia Swingle) yang mengandung polifenol terutama flavonoid. Tujuan penelitian ini untuk mengetahui pengaruh ekstrak kulit jeruk nipis (Citrus aurantifolia Swingle) konsentrasi 10% terhadap aktivitas enzim GTF Streptococcus mutans. Penelitian ini menggunakan ekstrak kulit jeruk nipis konsentrasi 10% sebagai perlakuan, chlorhexidine gluconate 0,12% sebagai kontrol positif, serta akuades steril sebagai kontrol negatif. Metode penelitian ini terdiri dari tiga tahap yaitu penyiapan ekstrak kulit jeruk nipis konsentrasi 10%, penyiapan enzim GTF dari supernatan Streptococcus mutans, dan pengujian aktivitas enzim GTF melalui analisis konsentrasi fruktosa dengan menggunakan High Performance Liquid Chromatography (HPLC). Pembacaan luas area fruktosa dilakukan berdasarkan waktu retensi. Satu unit aktivitas enzim GTF di definisikan sebagai 1 µmol fruktosa/ml dari enzim/jam. Selanjutnya data yang diperoleh dianalisis secara statistik dengan one way ANOVA.Hasil perhitungan aktivitas enzim GTF dengan one way ANOVA menunjukkan perbedaan yang signifikan antara kelompok perlakuan dengan kelompok kontrol negatif (p<0,05), dan tidak terdapat perbedaan yang signifikan dengan kontrol positif. Kesimpulan dari penelitian ini adalah ekstrak kulit jeruk nipis konsentrasi 10% dapat menghambat aktivitas enzim glukosiltransferase Streptococcus mutans. The Influence of 10% Concentrate of Citrus Aurantifolia Swingle on The Activities of Streptococcus Mutans Glucocyl Transferase Enzyme. Streptococcus mutans is a bacteria which has glucosyl transferase (GTF) enzyme and acts as the main agent that causes dental caries. GTF enzyme will convert sucrose into fructose and glucan. Lime peel (Citrus aurantifolia Swingle) is one of the traditional herbs which has flavonoid as an antibacterial agent. The purpose of this research is to investigate the effect of 10% concentration of lime peel extract (Citrus aurantifolia Swingle) to the activity of GTF enzyme Streptococcus mutans.This research used 10% concentration of  lime peel extract as the treatment, 0.12% chlorhexidine gluconate as a positive control, and distillate water as anegative control. The method of this research consists of three steps; preparing the lime peel extract concentration of 10%, preparing the GTF enzyme from the supernatant of Streptococcus mutans, and testing GTF enzyme activity by analyzing the fructose concentration using High Performance Liquid Chromatography (HPLC). Perusal of the fructose area was based on the retention time of fructose. One unit of GTF enzyme activity is defined as the 1 μmol fructose / ml of enzyme / hour.  The obtained data then were analyzed by one way ANOVA. The result showed a significant difference between treatment group with the negative control (p <0.05), and there are no significant difference with the positive control. This research concludes that 10% lime peel extract can inhibit the GTF enzyme activity of Streptococcus mutans.

scholarly journals Prevalence of Oral Microbial Flora during Orthodontic Space Closure: A Pilot Study

2020 ◽  
Author(s):  
Abirami Selvaraj ◽  
Sumathi Felicita ◽  
Smiline Girija
Keyword(s):  
Streptococcus Mutans ◽  
Bacterial Count ◽  
Lateral Incisor ◽  
Orthodontic Space Closure ◽  
Space Closure ◽  
Significant Difference ◽  
Maxillary Lateral Incisor ◽  
Post Hoc ◽  
One Way Anova ◽  
Paired T Test

Introduction: Orthodontic treatment with fixed appliances especially during the retraction stage makes it challenging to maintain the oral hygiene. Attachments used, such as elastic chains, loops and springs, result in changes in the oral environment due to the accumulation of plaque and increase in the levels of bacterial count mainly Streptococcus mutans and Lactobacilli species. Aim: To determine the prevalence of oral microbial flora during orthodontic space closure. Materials and Methods: This was a cross-sectional pilot study conducted during the month of December 2019 which consisted of eight patients who were randomly selected among the age group of 18-25 years. Mean and SD of age in Males (4) and Females (4) were 22±2.16 years and 22.25±1.70 years, respectively and had reported to the Department of Orthodontics of a private dental college, Saveetha Dental College. In each patient, after 6-8 months of orthodontic treatment, plaque samples were collected only once around the orthodontic brackets at the cervical aspect of the maxillary lateral incisor, maxillary premolar, mandibular canine, mandibular premolar in 1st, 2nd, 3rd, and 4th quadrant respectively, by the method of cotton swabbing for the evaluation of micro flora. Independent paired t-test and One-way ANOVA with Post-hoc Tukey HSD test were done to estimate the prevalence of microorganisms at different sites. Results: Independent paired t-test showed highly significant differences in the levels of Streptococcus mutans when compared to Lactobacillus (p<0.001) with mean values of 4.8±2.5 and 23.1±9.2 for Streptococcus and Lactobacillus, respectively. One-way ANOVA with Post-hoc Turkey HSD analysis showed significant difference at the region of maxillary lateral incisor compared to other sites whereas Lactobacillishowed no significant differences between the various sites tested (p-value<0.001). Kappa statistics was performed which revealed an inter examiner reliability of 0.91. Conclusion: During orthodontic space closure, bacterial count of Streptococcus mutans showed a statistically significant difference between different sites (maxillary lateral incisor, mandibular canines, maxillary and mandibular premolars) with highest being the maxillary incisor region followed by that of mandibular canines. However, the incidence of Lactobacillusacidophilus did not show any difference between the various sites evaluated.

scholarly journals The Difference of Antibacterial Power between Cocoa Peel (Theobroma Cacao L.) Extract 6% compared to Chlorhexidine Digluconate 2% Againts Streptococcus mutans (In vitro)

2021 ◽  
Vol 11 (1) ◽  
pp. 1
Author(s):  
Alissa Amanda ◽  
Tamara Yuanita ◽  
Galih Sampoerno
Keyword(s):  
Streptococcus Mutans ◽  
Theobroma Cacao ◽  
Inhibition Zone ◽  
Diffusion Method ◽  
Chlorhexidine Digluconate ◽  
Significant Difference ◽  
The Difference ◽  
Theobroma Cacao L ◽  
Peel Extract

Background: Before restoration, it is necessary to clean the cavity from the smear layer and residual bacteria such as Sreptococcus mutans using a 'gold standard' cavity cleanser, namely 2% Chlorhexidine digluconate (CHX), however CHX 2% has a disadvantage of having a toxic effect on fibroblasts, osteoblasts, myoblasts, odontoblast-like cells, Chinese hamster ovary cells, and buccal epithelial cells. The shortcomings of the 2% CHX triggered researchers to look for alternative cavity cleansers that are more biocompatible, namely cocoa peel extract because it contains of antibacterial compounds including alkaloids, flavonoids, tannins, saponins, and terponoids with a non-toxic 6% concentration. Purpose: To analyze the difference of antibacterial activity between cocoa peel extract with a concentration of 6% compared to chlorhexidine digluconate 2% against Streptococcus mutans. Methods: This research was an in vitro laboratory experimental study with the posttest only control group design which included two treatment groups, namely 6% cocoa peel extract and 2% CHX. This research was conducted using the inhibition zone diffusion method against S. mutans to see the antibacterial power of each sample. Results: There was a significant difference (p <0.05) in the mean diameter of the inhibition zone between 6% cacao peel extract, namely 11.5406 mm and CHX 2%, namely 13.2156 mm.  Conclusion: Chlorhexidine digluconate 2% has a greater antibacterial power than 6% cocoa peel extract (Theobroma cacao L.) against Streptococcus mutans. 

scholarly journals Kekerasan permukaan email setelah aplikasi gel karbamid peroksida 10%

2016 ◽  
Vol 8 (2) ◽  
pp. 118
Author(s):  
Pambudi Santoso T
Keyword(s):  
Mineral Water ◽  
Enamel Surface ◽  
Carbamide Peroxide ◽  
Significant Difference ◽  
Before And After ◽  
Alternative Material ◽  
Group 3 ◽  
Group 2 ◽  
One Way Anova ◽  
Control Post

The influence of strawberries as bleaching alternative material toward surfacemicrohardness of the teeth is still unknown so that a research should be conducted toquantitatively assess the effects of bleaching with 10% carbamide peroxide andblended strawberry paste on post-extracted incisive teeth by performing superficialmicrohardness analysis. Three groups of sample i.e. group 1 (control): post-extractedincisive teeth soaked in ordinary mineral water, group 2: soaked in carbamideperoxide 10% gel, and group 3: soaked in 100% strawberry paste. The microhardessof each sample group is tested before and after the application of bleaching materials.The result was there was significant difference of strawberry paste compared to CP10% gel and mineral water soaked incisive teeth. The data obtained are tabulated,then analyzed with one way Anova and LSD. It can be concluded that the applicationof carbamide peroxide 10% gel in 6 weeks doesn’t decrease the microhardness ofteeth enamel surface. However, the application of strawberry paste decreases themicrohardness of enamel surface

scholarly journals PREPARATION AND CHARACTERIZATION OF LOW MOLECULAR WEIGHT CHITOSAN WITH DIFFERENT DEGREES OF DEACETYLATION BY THE ACID HYDROLYSIS METHOD

2021 ◽  
pp. 153-164
Author(s):  
NAWZAT D. AL-JBOUR ◽  
M. D. H. BEG ◽  
JOLIUS GIMBUN ◽  
A. K. M. MOSHIUL ALAM
Keyword(s):  
Molecular Weight ◽  
Acid Hydrolysis ◽  
Water Solubility ◽  
Skeletal Structure ◽  
Low Molecular Weight ◽  
Molecular Weights ◽  
Hydrolysis Method ◽  
Significant Difference ◽  
Low Molecular Weight Chitosan ◽  
Pharmaceutical Industries

Objective: The objective of this research is to prepare Low Molecular Weight Chitosan (LMWC) by the acid hydrolysis method, using dilute hydrochloric acid (2M). LMWC has superior properties compared to the High Molecular Weight Chitosan (HMWC), especially in terms of water solubility, antibacterial and antifungal properties. These could open new potential applications for LMWC in sectors such as the cosmetics, food, and pharmaceutical industries. Methods: In this work, the acid hydrolysis method was used to produce LMWC with different molecular weights starting from 500 kDa and 93% degree of deacetylations (DDA). The molecular weights of the produced grades were determined by applying Mark-Houwink equation while the %DDA was determined and verified by the use of the 1st derivative UV method and 1HNMR method, respectively. The depolymerization reactions were carried out with different time intervals to produce totally deacetylated LMWC of 30 kDa, 15 kDa, and 7.5 kDa. The LMWC was characterized by FTIR, XRD, and DSC to evaluate the functionality, microstructure and thermal properties. Results: The FTIR spectra revealed that there is no significant difference in the main skeletal structure of the LMWC and HMWC. On the other hand, the XRD and DSC results showed that the LMWC of different molecular weights and degrees of deacetylation are of semi-crystalline structure, similar to the HMWC. Conclusion: The obtained results showed that the used acid hydrolysis procedure can produce LMWC grades of desired specifications, yields, and quality which are suitable for use in different applications.

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