Demineralization Process Research Articles

Synthesis and characterization of carboxymethyl shrimp chitosan (CMSCh) from waste shrimp shell

Chitin, the main component of shellfish such as crab and shrimp, is one of the most used biopolymers after cellulose. Today, although recycling of waste is becoming increasingly important, large quantities of seafood shells such as crab and shrimp are being destroyed around the world without much evaluation. Chitosan, which is non-toxic, biodegradable-biocompatible and has many application advantages compared to chitin, is used in many sectors, especially cosmetics, pharmaceuticals and agriculture, as it shows superior properties compared to other biopolymers in terms of chemical and physical properties. In this study, in order to evaluate waste shrimp shells (WSS), shrimp shells were first removed from their minerals and proteins by deproteinization, demineralization and deacetilization processes. Then, chitosan and carboxymethyl shrimp chitosan (CMSCh) were synthesized by isolation of chitin. The structures of Chitin-chitosan and CMSCh were characterized by spectroscopic methods (FT-IR, XRD and NMR) and the deacetylation degrees of them were calculated. Also, surface morphologies and thermal properties were analyzed by SEM and DTA-TG, respectively.

On the issue of composite materials

Caries is the pathological process of hard tissue demineralization in teeth caused by various factors. As a result, necrotic areas within the tooth are formed that require removal and subsequent reconstruction in order to re-establish tooth function. This is achieved by replacing the demineralized areas with dental filling materials. With a wide variety of available dental filling materials, the dentist is faced with the task of choosing the correct material depending on the nature of the lesion. To date, the most widely used permanent filling materials are composites, which constitute one of the largest groups of filling materials. They gained their popularity due to their numerous good qualities, and the continuous research within the field of dental materials enables further improvement of their properties. Currently, a new composite has appeared in dentistry, which helps to neutralize the salivary pH during acidosis, thereby preventing the development of dental caries

The Effect of Long-Term Antihypertensive Therapy on the Change in Secretion and Calcium, Bicarbonate and Phosphate Ion Concentration in Non-Stimulated and Stimulated Saliva.

ObjectiveThe aim of this study was to evaluate the amount of saliva secreted and calcium, bicarbonate, and phosphate ion concentration in patients receiving antihypertensive for five years or over five years (patient group) and in healthy patients (control group).Material and methodsThe patient or experimental group included 31 subjects who were admitted to a cardiovascular clinic and had been receiving an antihypertensive drug therapy for more than five years. The control group included 31 healthy subjects. The measured amount of saliva was further used to determine the calcium, phosphate and bicarbonate ion concentration values. Calcium and phosphate ions were determined spectrophotometrically, while bicarbonate ions were determined by titration.ResultsA two-way-test (Student's test) was used to compare the values of variables. The amount of excreted saliva was statistically significantly lower in the patient group in non-stimulated (1.739 mL/5 min) and stimulated saliva (3.594 mL/5 min). Calcium ion concentration was statistically significantly lower in patient group in resting saliva (6.143 mg/dL). Bicarbonate and phosphate ion concentration in patient group was statistically significantly higher in non-stimulated (bicarbonate ion = 14.041 mmol/L, phosphate ion = 2.818 μmol/L) and stimulated saliva (bicarbonate ion = 10.872 mmol/L, phosphate ion = 1.454 μmol/L), respectively.ConclusionA reduced amount of saliva and calcium ion concentration indicates the possibility of a higher frequency of hard dental tissue demineralization process. On the contrary, the increase in the phosphate and bicarbonate ion concentration in the patient group affects the regulation of acid-base balance, thus having a preventive effect.

Establishment of microcosm biofilm models that reproduce a cariogenic diet intake

Biofilms were developed from human saliva on bovine enamel discs in four experimental conditions to investigate dental caries development: feast and famine (M1), abundance and scarcity (M2), three meals daily (M3), and three meals plus two snacks daily (M4). The main difference between these models was the diet for microbial growth. The evaluations included verifying the pH of the spent culture media and analyzing the enamel discs for demineralization (microhardness and roughness) and biofilms (biomass, viable populations of mutans streptococci, and total microbiota). Two major behaviors were observed: M1 and M2 promoted an acidic environment, while M3 and M4 maintained pH values closer to neutral. The demineralization process was slower in the neutral groups but more pronounced in M3, while a greater increase in microbiota and biomass was observed over time for both neutral groups. Thus, the M3 model was better at mimicking the oral environment that leads to demineralization.

Transverse Micro Radiography Analysis of the Effect of Experimental Calcium-Containing Primer System on Demineralized Enamel

Background: Enamel mineral density is dependent on a balanced dynamic process of demineralization and remineralization. Objective: We evaluated the remineralization potential of experimental calcium- containing primer (CaP) application on enamel subsurface lesions. Methods: Demineralized enamel samples obtained from bovine incisor teeth were prepared and cut buccolingually. All samples were divided into 4 main groups according to the type of primer: CLEARFIL SE BOND 2 Primer (SEP), experimental calcium-containing primer (CaP) and bond: CLEARFIL SE BOND 2 Bond (SEB), CLEARFIL Protect Bond (PBB) treatment: (1) SEP-SEB (2) SEP-PBB (3) CaP-SEB (4) CaP-PBB. Each group was subdivided according to storage time in artificial saliva: immediately, 1 month and 6 months. Then, the samples were analyzed using transverse micro radiography (TMR). Additionally, the samples treated with each primer were prepared for scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS) observation. Two-way ANOVA was used for the statistical analysis of mineral loss (ΔZ: vol%·µm). Results: CaP-PBB had the significantly lowest ΔZ at all storage times, while SEP-SEB had the highest ΔZ (p < 0.05). SEM observations revealed that new crystals were formed on the surface after 6 months, and the ratio of calcium on the enamel increased in the EDS analysis. Conclusion: Experimental calcium-containing primer can provide additional mineral deposition, with even further deposition when combined with a fluoride-containing bond.

Ekstraksi Gelatin Tulang Ikan Gabus (Channa striata) Dengan Variasi Asam Yang Berbeda Pada Proses Demineralisasi

Palembang is the capital city of South Sumatra Province which has special foods which main raw material is fish. Many pempek entrepreneurs use cork fish meat for pempek raw material resulting in abundance of cork fish bone waste, therefore researchers utilize cork fish bone waste as an alternative into raw material in making gelatin. In this study, researchers used several weak acids derived from natural ingredients such as lime extract and starfruit extract and as a comparison researchers used synthetic weak acids namely citric acid in the market. The purpose of this research used several types of acids in the demineralization process to produce better gelatin production. This study used a Completely Randomized Design, with several acid treatments with and consisting of 3 (three) treatment levels, each treatment was repeated 3 times. The treatment in this study was a demineralization process with the addition of citric acid was (A1), lime extract was (A2), and starfruit extract was (A3). The parameters examined in this study include: Gelatin yield, Gelatin acidity (pH), Moisture and Sensory content (color and aroma). Data from proximate observations were analyzed by analysis of variance (ANOVA) and further tested based on the coefficient of diversity. From the results of this study, it was found that the best treatment of using variations in acid was gelatin demineralized using citric acid which produced a yield was 6%, a moisture content was 9.21%, pH 6, the panelist's favorite value of color was 4.3 and aroma 3, 8.

Changes in Bone Metabolism and Structure in Primary Hyperparathyroidism

Abstract Parathyroid hormone (PTH) is a key regulator of bone turnover. Depending on the duration of action, the hormone causes catabolic and anabolic effects by binding with specific receptors (PTHR1) in the bone. Various cells expressing PTHR1 on their surface are involved in the process – osteoblasts, osteocytes, bone marrow stromal cells, T-lymphocytes and macrophages. In physiological conditions PTH balances the bone metabolism. Intermittent pharmacological doses of PTH lead to the prevalence of bone formation and are used in the treatment of osteoporosis. Persistently elevated levels of PTH stimulate bone resorption by impacting mainly the cortical bone. New imaging and analysis techniques show that high PTH levels can also have an adverse effect on trabecular microarchitecture. Primary hyperparathyroidism (PHPT) is a disease characterized by increased bone metabolism, decreased bone mineral density (BMD), inadequate osteoid mineralization and an increased risk of fractures. Prolonged overproduction of PTH leads to stimulation of bone resorption and defects in bone formation, mainly causing loss of cortical bone mass, while in the trabecular bone predominate demineralization processes. One explanation of these findings is the enhanced stimulation of RANKL expression by osteoblasts with decreased OPG expression and bone formation at the same time.

Recovery Kitin Dari Limbah Cangkang Rajungan

The small crab animal is important for the fisheries sector in Indonesia, but usually the small crab industry only takes meat and allows the crab shell to become a pile of waste. To reduce the potential for pollution caused by a small crab shell waste, the waste can be reused to obtain chitin. Small crab shell waste still contains quite a lot of chemical compounds, including protein, minerals (CACO), and chitin. The study conducted chitin extraction with a process preceded by deproteination and then demineralization. Chitin was characterized using Fourier Transform Infra Red (FTIR) and Scanning Electron Microscopy (SEM). The results showed that chitin was successfully extracted from the small crab shell through the deproteination and demineralization process with FTIR l, which results the characteristic spectrum of chitin compounds such as waves of 3433 cm 'for -OH, -NH groups. The absorption around the wave number 3433 cm occurs because of the overlap between the absorption -NH and -OH and the wave number 701 cm 'for the b-1,4-glycosidic group.

Autogenous Tooth Bone Graft and Simvastatin Combination Effect on Bone Healing.

Autogenous tooth bone grafts (ATGM) are materials prepared from extracted teeth and have been used for bone augmentation. These graft materials are known to have similar structures and components to bone grafts. In this sense, this study aimed to evaluate all the tooth layers mixed with simvastatin without any demineralization process effect on bone formation. In 60 Wistar albino rats, a standardized 6.0 m-diameter critical size bone defect was created in their calvarium. The study consists of 1 control and 4 experimental groups. In the control group (12 rats), the defects were left empty. The defects were grafted only with ATGM in Group 1, with ATGM mixed with simvastatin in Group 2, autogenous bone graft mixed with simvastatin in Group 3, and with xenogenic bone graft mixed with simvastatin in Group 4. The animals were sacrificed at the 7th and 28th days after operation. PCR, micro CT and histological results show that bone formation was enhanced in the experimental groups in comparison to the control group. Group 1 and Group 2 had similar bone formation rate when compared to Group 3 and Group 4 at the 28th day after operation. This study concludes that mineralized teeth may be used for defect reconstruction without any demineralization process. Autogenous mineralized tooth bone graft should be mixed with simvastatin for bone regeneration like other grafts.

Denmark: WindSpace & EWI – carbon black from scrap tyres

This work deals with the recovered carbon black derived from the industrial-scale pyrolysis of end-of-life tires, targeting at increasing the technical knowledge to be considered as alternative to the virgin carbon black. Accordingly, a demineralization process using HCl, HNO3 and NaOH to improve the properties of the recovered carbon black is investigated. A fractional factorial design 2k-2 showed that the acid concentration has the highest statistical influence on the ash reduction. At 5 M, the ash content was 6.12 wt% and 5.21 wt% for HCl and HNO3, respectively. The demineralized recovered carbon black obtained from both acids together with a reference carbon black (N550) were characterized by elemental and proximate analyses, surface area, ash composition by XRF, and morphology by SEM and TEM. A comprehensive surface chemistry analysis by FTIR and TPD-NH3 was also conducted. In addition to decreasing the ash content and to increasing the surface area, the recovered carbon black treated with HNO3 led to the highest presence of acidic functional groups. In this regard, this upgraded recovered carbon black is expected to offer both better filler/polymer interaction and in-rubber performance, as compared to the non-treated recovered carbon black. The experience gained from this work provides important impetus to deem the recovered carbon black as alternative to virgin carbon black, and paves the way to close the end-of-life tire-recycling loop by both pyrolysis and chemical upgrading strategies.

Korea, South: LG Chem – carbon nanotubes, as carbon black substitute

This work deals with the recovered carbon black derived from the industrial-scale pyrolysis of end-of-life tires, targeting at increasing the technical knowledge to be considered as alternative to the virgin carbon black. Accordingly, a demineralization process using HCl, HNO3 and NaOH to improve the properties of the recovered carbon black is investigated. A fractional factorial design 2k-2 showed that the acid concentration has the highest statistical influence on the ash reduction. At 5 M, the ash content was 6.12 wt% and 5.21 wt% for HCl and HNO3, respectively. The demineralized recovered carbon black obtained from both acids together with a reference carbon black (N550) were characterized by elemental and proximate analyses, surface area, ash composition by XRF, and morphology by SEM and TEM. A comprehensive surface chemistry analysis by FTIR and TPD-NH3 was also conducted. In addition to decreasing the ash content and to increasing the surface area, the recovered carbon black treated with HNO3 led to the highest presence of acidic functional groups. In this regard, this upgraded recovered carbon black is expected to offer both better filler/polymer interaction and in-rubber performance, as compared to the non-treated recovered carbon black. The experience gained from this work provides important impetus to deem the recovered carbon black as alternative to virgin carbon black, and paves the way to close the end-of-life tire-recycling loop by both pyrolysis and chemical upgrading strategies.

US: Monolith – carbon black

This work deals with the recovered carbon black derived from the industrial-scale pyrolysis of end-of-life tires, targeting at increasing the technical knowledge to be considered as alternative to the virgin carbon black. Accordingly, a demineralization process using HCl, HNO3 and NaOH to improve the properties of the recovered carbon black is investigated. A fractional factorial design 2k-2 showed that the acid concentration has the highest statistical influence on the ash reduction. At 5 M, the ash content was 6.12 wt% and 5.21 wt% for HCl and HNO3, respectively. The demineralized recovered carbon black obtained from both acids together with a reference carbon black (N550) were characterized by elemental and proximate analyses, surface area, ash composition by XRF, and morphology by SEM and TEM. A comprehensive surface chemistry analysis by FTIR and TPD-NH3 was also conducted. In addition to decreasing the ash content and to increasing the surface area, the recovered carbon black treated with HNO3 led to the highest presence of acidic functional groups. In this regard, this upgraded recovered carbon black is expected to offer both better filler/polymer interaction and in-rubber performance, as compared to the non-treated recovered carbon black. The experience gained from this work provides important impetus to deem the recovered carbon black as alternative to virgin carbon black, and paves the way to close the end-of-life tire-recycling loop by both pyrolysis and chemical upgrading strategies.

Evaluation of Remineralisation Potential of Zingiber officinale Roscoe-Apis Mellifera, and Chitosan as compared to control using QLF on white spot lesions: An in-vitro study

Early detection and treatment of white spot lesions (WSL) is pivotal in caries control. Several commercially available products are available for WSL reversal. However, the majority of them are either synthetically derived or are not a hundred percent efficient. Thus there is an ever constant need to find newer, more efficacious products for the same. One of the parameters to quantify de and remineralization is by Quantitative Light Induced Fluorescence (QLF). Thus this study aims to evaluate and compare the remineralizing potential of Zingiber officinale Roscoe (Ginger rhizome), Apis Mellifera (Manuka Honey) mixture and chitosan on artificial demineralized human enamel using Quantitative Light Induced Fluorescence. 45 human enamel samples were randomly divided into a control and two test groups. An Area of Interest (AOI) measuring 4x4 mm on the buccal surface of each tooth was formed and all the samples were subjected to demineralization process for a period of 96 hours. Remineralization regime was then carried out with twice daily application of respective interventional agents for a period of 21 days. QLF readings were recorded at the end of demineralization (Baseline), Day 7, Day 14 and Day 21 and fluorescence images were analysed using QLF InpektorTM propriety software. The remineralization action of chitosan was found to be the highest with a statistically significant reduction (p<0.001) seen at the end of 7th, 14th and 21st day. Ginger- honey mixture also showed reduction in fluorescence levels but only after the 14th day. The current study showcases the dramatic ability of chitosan to almost completely reverse artificially formed WSL at each subsequent week. Ginger honey on the other hand showed a significant remineralization between 2nd and 3rd week which may be attributed to a possible slower mechanism of action.

Finite Element Modelling and Experimental Validation of the Enamel Demineralisation Process at the Rod Level

In the past years, a significant amount of effort has been directed at the observation and characterisation of caries using experimental techniques. Nevertheless, relatively little progress has been made in numerical modelling of the underlying demineralisation process.The present study is the first attempt to provide a simplified calculation framework for the numerical simulation of the demineralisation process at the length scale of enamel rods and its validation by comparing the data with statistical analysis of experimental results.FEM model was employed to simulate a time-dependent reaction-diffusion equation process in which H ions diffuse and cause demineralisation of the enamel. The local orientation of the hydroxyapatite crystals was taken into account. Experimental analysis of the demineralising front was performed using advanced high-resolution synchrotron X-ray micro-Computed Tomography. Further experimental investigations were conducted by means of SEM and STEM imaging techniques.Besides establishing and validating the new modelling framework, insights into the role of the etchant solution pH level were obtained. Additionally, some light was shed on the origin of different types of etching patterns by simulating the demineralisation process at different etching angles of attack.The implications of this study pave the way for simulations of enamel demineralisation within different complex scenarios and across the range of length scales. Indeed, the framework proposed can incorporate the presence of chemical species other than H ions and their diffusion and reaction leading to dissolution and re-precipitation of hydroxyapatite. It is the authors’ hope and aspiration that ultimately this work will help identify new ways of controlling and preventing caries.

Genetic characterisation of wild ungulates: successful isolation and analysis of DNA from widely available bones can be cheap, fast and easy.

Genetic characterisation of wild ungulates can be a useful tool in wildlife management and in obtaining a greater understanding of their biological and ecological roles in a wider spatiotemporal context. Different ways of optimising methodologies and reducing the costs of genetic analyses using widely available bone tissues collected within regular hunting allocations were examined. Successful isolation and analysis of DNA from widely available bones can be cheap, fast and easy. In particular, this study explored the possibility of using bones for extracting high quality nuclear DNA for microsatellite analysis. The utility of applying a modified demineralisation process using two commercially available DNA isolation kits, which differ significantly in price, was evaluated. The sample sets included bones and, for comparison, muscle tissues from four wild ungulate species: chamois (Rupicapra rupicapra), roe deer (Capreolus capreolus), wild boar (Sus scrofa), and Alpine ibex (Capra ibex). For the recent bones, these results confirmed that the DNA concentrations and microsatellite amplification were sufficiently high, even when using low-cost kits, after prior demineralisation. For old bones, prior demineralisation and use of a specially designed isolation kit led to a more successful extraction of DNA. Besides reducing kit-related costs, low-cost kits are much faster and therefore make genetic analysis more efficient.

Influences of chemically controlled Ca-bearing minerals in chitosan on Pb2+ removal efficiency.

Highly purified chitosan was generally preferred for heavy metal (HM) removal and the preparation parameters varied largely without any agreement. This study investigated to the influences of chitin with different purities on the HM removal of corresponding chitosan. Sea shrimp waste was used as raw materials and Pb2+ was used as target HM. The results of orthogonal experimental analysis showed that only acid concentration played an important role in the deproteinization and demineralization processes of the chitin preparation under HCl, H2SO4 and CH3COOH treatment. Ca-bearing minerals (CBM) but not free -NH2 group of chitosan played a major role in the removal of Pb2+ from solution. Partly purified chitosan mainly removed Pb2+ by precipitation and then biosorption. The dissociation of Ca2+ from CBM elevated pH value of Pb2+ solution which benefited to precipitation and the formation of NH2-Pb2+. Partly purified chitosan prepared from HCl and CH3COOH treated chitin showed 720-753mg/g of Pb2+ adsorption at the initial pH value of 6.0; however, highly purified chitosan prepared from HCl treated chitin showed only 45-160mg/g. Chitosan prepared from H2SO4 treated chitin showed 720-752mg/g of Pb2+ adsorption. This research found the unexplored information for the industrial application of chitosan with minimum cost but the highest HM removal efficiency.

UTILIZATION OF CHITOSAN FROM SHRIMP SHELLS WASTE FOR REDUCTION IRON (Fe) METAL CONTENT IN MARTAPURA RIVER

The Martapura River in South Kalimantan contains quite high levels of metals, namely Fe metal which allows the presence of excessive metal elements. According to KEPMENKES, clean water standards contain Fe of 0.3 mg/L. Based on testing, the Fe content contained in the Martapura River water was 2.8 mg/L. One effort to reduce the content of these metals is using adsorbents made from shrimp shells. This shrimp shell waste contains chitin, so if further treatment is given, it is expected to be used as an adsorbent to reduce Fe levels in the Martapura River.The study was conducted using shrimp shells with sizes of 1000 microns, 710 microns and 500 microns. This shrimp shell is deproteinized, the shrimp shell is added with a 3.5% NaOH solution (w/v). Then the demineralization process is carried out, where the dry residue obtained from the previous process is added with 1N HCl solution in a ratio of 1:15 (w/v). From this process chitin is produced, then chitin is deacetylized with 50% NaOH (w/v). Then the samples were tested with a DR-2500 spectrophotometer after being passed to a continuous adsorption device. From the results of the study, it was found that chitosan is very effective in reducing Fe metal content in the Martapura River, the quality of clean water produced reaches the clean water quality standards set. The results of the study at 500 microns size obtained the smallest Fe metal content of 0.05 mg/L.

The effect of different fluoride varnishes on the release of calcium ions from hydroxyapatite discs: An ion-selective electrodes study

Introduction: Recently, various modes of fluoride varnishes have evolved, each with its own recommended concentration, potentially active ingredients, and flavour, leading to a claim of additional preventive benefits. Differences in fluoride release patterns can potentially enhance or reduce the efficacy of fluoride varnishes. Numerous clinical trials have proven its ability in preventing and arresting dental caries. This study mainly focused on the investigations of the apatite demineralisation process under the effect of different fluoride varnishes by ion-selective electrodes (ISE), in an attempt to comprehend their mechanism in anti-caries. Methods: Four different fluoride varnishes (Fluor Protector S, Duraphat, ClinPro White, MI Varnish) were used to measure their effect on the demineralisation process of the hydroxyapatite (HAP) discs in 60ml pH 4.0 acetic solutions. The HAP discs were treated with these varnishes after 4-hours demineralisation and then immersed back into the same solutions for further demineralisation to observe the effect of the varnishes. Throughout the experiment, the calcium ISE was used to monitor the rate of calcium concentration. Results: The result demonstrated that ClinPro White varnish resulted in the most significant inhibition of demineralisation and signs of probable remineralisation throughout the experiment. Other fluoride varnishes treatment showed the ability to inhibit demineralisation. However, the rate of calcium dissolution was not significantly different from different varnishes. The fact that the ClinPro White showed evidence of remineralisation might be associated with the fact that the varnish contained a source of calcium and phosphate. Conclusion: The fluoride varnishes treatment is shown to be effective in inhibiting the demineralisation of apatite regardless of the difference in fluoride concentration and potentially active ingredients incorporated in some of the fluoride varnishes.

An Investigation into the Applicability of Pyrolyzed Tyre Char and Tyre Crumb for the Recovery of Gold from Acidic Solutions

The present study has assessed the performance of pyrolytic tyre char and tyre crumb as cheap adsorbents for gold recovery from acidic solutions. The performances of the aforementioned cheap adsorbents, prior to and after undertaking demineralisation operations, were also investigated. Demineralisation of the adsorbents was undertaken via the application of 1 M sodium hydroxide and 1M nitric acid at a temperature of 90 °C for a duration of 24 h with changes in BET surface areas (SBETs) and adsorption performances, subsequently evaluated. Initial investigations established that the pH value of 2 constituted the preferred pH at which adsorption was enhanced, thus this pH was maintained while undertaking subsequent kinetic and equilibrium adsorption experiments. Based on the experimental investigations, it was demonstrated that the kinetics and adsorption of gold ions (Au3+) as AuCl4− anions from acidic solutions was best described using pseudo second order kinetic and Langmuir equilibrium isotherm models, respectively. Even though the demineralisation process resulted in a notable increase in BET surface areas (SBETs) for both char (23%) and crumb (984%), it was found to negatively influence adsorbent loading of Au3+ ions onto the adsorbents. It was therefore suggested that sulphur removal via demineralisation may explain the reduced adsorbent loading since there is typically an affinity of gold ions (Au3+) for localised elemental sulphur. This affinity causes sulphur to be oxidised into solution and the gold ions (Au3+) to be reduced to elemental gold on the adsorbent surface. The present study was therefore able to demonstrate the preference for untreated of pyrolytic tyre char and to a lesser extent, untreated crumb, as alternative low-cost adsorbents for gold recovery from acidic solutions.

The Potential of Insects as Alternative Sources of Chitin: An Overview on the Chemical Method of Extraction from Various Sources.

Chitin, being the second most abundant biopolymer after cellulose, has been gaining popularity since its initial discovery by Braconot in 1811. However, fundamental knowledge and literature on chitin and its derivatives from insects are difficult to obtain. The most common and sought-after sources of chitin are shellfish (especially crustaceans) and other aquatic invertebrates. The amount of shellfish available is obviously restricted by the amount of food waste that is allowed; hence, it is a limited resource. Therefore, insects are the best choices since, out of 1.3 million species in the world, 900,000 are insects, making them the most abundant species in the world. In this review, a total of 82 samples from shellfish—crustaceans and mollusks (n = 46), insects (n = 23), and others (n = 13)—have been collected and studied for their chemical extraction of chitin and its derivatives. The aim of this paper is to review the extraction method of chitin and chitosan for a comparison of the optimal demineralization and deproteinization processes, with a consideration of insects as alternative sources of chitin. The methods employed in this review are based on comprehensive bibliographic research. Based on previous data, the chitin and chitosan contents of insects in past studies favorably compare and compete with those of commercial chitin and chitosan—for example, 45% in Bombyx eri, 36.6% in Periostracum cicadae (cicada sloughs), and 26.2% in Chyrysomya megacephala. Therefore, according to the data reported by previous researchers, demonstrating comparable yield values to those of crustacean chitin and the great interest in insects as alternative sources, efforts towards comprehensive knowledge in this field are relevant.