Chemical Hydrolysis Research Articles

Fabrication and Characterization of Glucosamine Hydrochloride from Chitin of Horseshoe Crab Shell (Tachypleus gigas)

Preparation of glucosamine hydrochloride from the chitin of horseshoe crab shells using the chemical hydrolysis method has been done using HCl concentration variation ratios of 7%, 9%, 11%,14 % with a ratio of 9:1 (v/w) for 4 hours at a temperature of 90ºC. Determination of glucosamine hydrochloride characteristics was characterized using Fourier transform-infra red (FT-IR) spectroscopy, in which the characteristics of glucosamine hydrochloride obtained in the OH group of glucosamine hydrochloride were 3446 cm-1 (s), 3448 cm-1 (s), 3450 cm-1 (s), 3448 cm-1 (s), respectively. For NH group of glucosamine hydrochloride were 1557 cm-1 (s), 1559 cm-1 (s), 1556 cm-1 (s), 1560 cm-1 (s), respectively. For CN group of glucosamine hydrochloride were 1379 cm-1 (m), 1379 cm-1 (m), 1379 cm-1 (m), 1379 cm-1 (m), respectively. While the glycoside bond of glucosamine hydrochloride 1073 cm-1 (w), 1074 cm-1 (w), 1074 cm-1 (w), 1074 cm-1 (w), respectively. Determination of the concentration of glucosamine hydrochloride with Ultraviolet Spectrophotometer analysis at a maximum wavelength of 197 nm with a standard solution of N-acetyl glucosamine in a solution of phosphate acid 0.005%, in which obtained the concentration of glucosamine hydrochloride 7% = 33.67 ppm, 9% = 36.35 ppm, 11% = 40.16 ppm, 14% = 43.97 ppm.

Engineering of Leuconostoc citreum for Efficient Bioconversion of Soy Isoflavone Glycosides to Their Aglycone Forms.

Soy isoflavones are phytochemicals that possess various beneficial physiological properties such as anti-aging, anti-tumor, and antioxidant properties. Since soy isoflavones exist in glycoside forms, their bioavailability requires initial hydrolysis of the sugar moieties bound to them to be efficiently absorbed through the gut epithelium. Instead of conventional chemical hydrolysis using acids or organic solvents, alternative strategies for enhancing the bioavailability of soy isoflavones using biological methods are gaining attention. Here, we engineered Leuconostoc citreum isolated from Korean kimchi for efficient bioconversion of soy isoflavone glycosides into their aglycone forms to enhance their bioavailability. We first constructed an expression module based on the isoflavone hydrolase (IH)-encoding gene of Bifidobacterium lactis, which mediates conversion of isoflavone glycosides to aglycone forms. Using a high copy number plasmid and bicistronic expression design, the IH was successfully synthesized in L. citreum. Additionally, we determined enzymatic activity of the IH using an in vivo β-glucosidase assay and confirmed its highly efficient bioconversion efficiency for various types of isoflavone glycosides. Finally, we successfully demonstrated that the engineered L. citreum could convert isoflavone glycosides present in fermented soymilk into aglycones.

Semisynthetic transformation of banana peel to enhance the conversion of sugars to 5-hydroxymethylfurfural

This study aimed to efficiently convert banana peels (BP) into 5-hydroxymethylfurfural (HMF) by using an integrated mechanoenzymatic/catalytic approach. There is no report on HMF production using mechanoenzymatic hydrolysis. Moreover, this method enables saccharification of lignocellulose without bulk solvents or pretreatment. The effects of the reaction volume, milling time, and reactive aging (RAging) on the mechanoenzymatic hydrolysis of BP were studied. The solvent-free enzymatic hydrolysis of BP under RAging conditions was found to provide higher glucose (40.5 wt%) and fructose (17.2 wt%) yields than chemical hydrolysis. Next, the conversion of the resulting monosaccharides into HMF in the presence of the AlCl3·H2O/HCl-DMSO/H2O system resulted in 71.9 mol% yield, which is so far the highest HMF yield obtained from cellulosic food wastes. Under identical reaction conditions, direct conversion of untreated BP to HMF yielded 22.7 mol% HMF, suggesting that mechanoenzymatic hydrolysis greatly promotes the release of sugars from BP to improve HMF yield.

Piperhancosides A−C, new lignan glycosides from the stems of Piper hancei Maxim

Three new lignan glycosides, piperhancosides A−C (1−3), and two known compounds (4−5) were isolated from the n-BuOH extract of the stems of Piper hancei Maxim. The planar structures of the new compounds were elucidated by extensive spectroscopic analyses. Their relative and absolute configurations were determined by coupling constants, chemical shift differences, acid hydrolysis, enzymatic hydrolysis, and experimental ECD spectra. All the isolates were evaluated for their antineuroinflammatory and antioxidant activities, and compounds 4 and 5 showed significant DPPH.+ radical scavenging ability with EC50 value of 14.07 and 16.48 μM, respectively.

Antibacterial activity of Chito-oligosaccharides derived from Fish Scales

This study aimed to evaluate the antibacterial activity of chito-oligosaccharides (COS) from Tilapia fish scales. There is a massive potential in sustainably prospecting from these resources: algae, vertebrate, crustaceans, molluscs, residues from fish farms, and fisheries such as bones, skin, and fins, internal organs and non-bio-degradable substances such as scales—the production COS achieved by chemical hydrolysis involving demineralization, deproteinization and deacetylation. The antibacterial activities performed against Staphylococcus aureus, Bacillus cereus, Streptococcus agalactiea, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi. The bacteriostatic and bactericidal effect measured by taking Minimum Inhibitory Concentrations (MIC), and the Minimum Bactericidal Concentrations (MBC). Chitin yielded 32.74% from 100 grams of dried fish scales in this study, whereas Chito-oligosaccharides yielded 24.12% from 100 grams of chitin. The ratio of MBC/MIC determination reveals the bacteriostatic and bactericidal effect of a COS. The bactericidal properties were visible in COS. The potential antibacterial effect of COS obtained by Tilapia fish scales could be utilized for biomedical purposes such as wound healing.

Impact of Saccharomyces cerevisiae and non-Saccharomyces yeasts to improve traditional sparkling wines production

In this study the effect of a co-inoculum of S. cerevisiae (F6789) with Torulaspora delbrueckii (TB1) or Starmerella bacillaris (SB48) on the oenological and aroma characteristics of sparkling wines obtained with the Champenoise method was investigated. The autolytic outcome and the sensory profile of sparkling wines were also evaluated. The secondary fermentations were completed by all mixed and single starter cultures with the only exception of those guided by Starm.bacillaris. Sparkling wines produced with S. cerevisiae F6789+Starm.bacillaris SB48 showed the highest amounts of glycerol (6.51 g/L). The best autolytic potential was observed in sparkling wines produced with +Starm.bacillaris (81.98 mg leucin/L) and S. cerevisiae+T. delbrueckii (79.03 mg leucin/L). The lowest value was observed for sparkling wines obtained with S. cerevisiae F6789 (53.96 mg leucin/L). Sparkling wines showed different aroma and sensory profiles. Esters were mainly present in sparkling wines obtained with S. cerevisiae F6789 (88.09 mg/L) followed by those obtained with S. cerevisiae+T. delbrueckii (87.20 mg/L), S. cerevisiae +Starm.bacillaris (81.93 mg/L). The content of esters decreased over time, and that might be related to the adsorption on lees and chemical hydrolysis. The highest concentrations of higher alcohols were found in sparkling wines produced with S. cerevisiae+T. delbrueckii (27.50 mg/L). Sparkling wines obtained with S. cerevisiae +Starm.bacillaris were well differentiated from the others due to their high score for the descriptor for spicy, bread crust, freshness and floral.Tailored strains with different autolytic potential might represent an interesting strategy to improve traditional sparkling wine production and favour their differentiation.

Chemical Constituents With Antiproliferative Activity From Pogostemon cablin (Blanco) Benth.

Two new patchoulene sesquiterpenoid glycosides (1–2), a natural patchoulane-type sesquiterpenoid (3) and a natural cadinene-type sesquiterpenoid (4), were isolated from the aerial parts of Pogostemon cablin (Blanco) Benth., together with eleven known sesquiterpenoids (5–15) and eleven known flavonoids (16–26). Their chemical structures were elucidated on the basis of spectroscopic methods, including NMR, HRESIMS, IR, and CD spectroscopic data analysis, as well as chemical hydrolysis. The isolated compounds 1–13 and 15–26 were tested for inhibitory effects on the proliferation of HepG2 cancer cells. Among them, compounds 17 and 19 displayed anti-proliferative effects against HepG2 cells with IC50 values of 25.59 and 2.30 μM, respectively. Furthermore, the flow cytometry analysis and Western blotting assays revealed that compound 19 significantly induced apoptosis of HepG2 cells by downregulating the ratio of Bcl-2/Bax and upregulating the expression of cleaved caspase-3 and cleaved caspase-9. Therefore, the potential pharmaceutical applications of P. cablin would be applied according to our study findings.

EVALUACIÓN DE PROCESOS COMBINADOS: PURIFICACIÓN DE QUITINA A PARTIR DE EXOESQUELETOS DE CAMARÓN (Penaeus sp) Y CHAPULÍN (Sphenarium purpurascens)

<p><strong>Background</strong>. Chitin is found in high concentration in insects, this being a new source of exploitation, due to the similarity in the content of chitin in exoskeletons of crustaceans compared to insects, especially those considered pests. <strong>Objective</strong>. Evaluate and compare the biological process of solid medium fermentation (SMF) combined with three treatments: ultrasonication, chemical and enzymatic hydrolysis in the purification of chitin from shrimp (<em>Penaeus sp</em>) and grasshopper (<em>Sphenarium purpurascens</em>) exoskeletons. <strong>Methodology</strong>. It consisted of the implementation of a pretreatment by fermentation in a solid medium (SMF) with chitinous samples (shrimp and grasshopper) combined with ultrasonication (20 kHz, 750 W, 120 min, 30 °C, 1/20 p/v), hydrolysis chemical (0.4 M NaOH, 0.6 N HCl, 38% NaClO, 1/15 p/v, 25 °C, 4 h) and enzymatic (Alcalase<sup>®</sup> 2.4L, 1:2 E:S, pH 7.5, 70 °C, 150 rpm, 300 min). <strong>Results</strong>. The combined treatments of SMF-ultrasonication, SMF-chemical hydrolysis, and SMF-enzymatic hydrolysis showed a higher percentage of deproteinization (84.82, 94.67, and 80.45%) and demineralization (82.12, 95.58, and 52%) with shrimp exoskeletons compared to shrimp exoskeletons grasshopper percentages (76.38, 92.04 and 78.71%) and (79.39, 95.37 and 51.79%) respectively. <strong>Implications</strong>. The chemical treatment generated greater protein and mineral removal compared to the other treatments, reaching yields of 54.45% in shrimp and 51.88% in grasshoppers. <strong>Conclusion</strong>. Ultrasonic waves extracted chitin in a shorter time (2h) with yields of 74.43% in shrimp and 78.02% in grasshoppers, reducing the amount of water.</p>

The interactive effect of dietary inclusion levels and preparation methods of myo-inositol on growth performance, antioxidant function and lipid metabolism homeostasis of Cyprinus carpio var. jian

To evaluate the interactive effect of inclusion levels (IL) and preparation methods (PM) of myo-inositol (MI) on growth performance, hepatic antioxidant capacity and lipid metabolism of Cyprinus carpio var. jian, five isonitrogenous and isoenergetic diets were formulated at a high level of dietary fat content (11.3%, HF basic diet), supplemented with 400 mg/kg or 800 mg/kg of enzyme biocatalysis MI (E-MI) (400E-MI, 800E-MI) and chemical acid hydrolysis MI (C-MI) (400 C-MI, 800 C-MI). 300 healthy C. Carpio var. jian (1.5 ± 0.1 g) were randomly fed one of the five experimental diets in triplicates (20 fish per tank) for 66 days. After the 66 days feeding trial, the growth performance, plasma biochemistry, hepatic antioxidant enzyme activities, and gene expressions related to lipid metabolism were determined. Two-way ANOVA analysis showed that PM and IL of dietary MI had an interactive effect on growth performance, antioxidant capacity and lipid metabolism of C. Carpio var. jian. The IL significantly affected protein deposition rate (PDR), activities of hepatic CAT, T-SOD and GPx (P < 0.05). Specifically, final average weight (FBW), weight gain rate (WGR), specific growth rate (SGR) and PDR in the 400E-MI group and 800 C-MI group were significantly higher than those in the 400 C-MI group (P < 0.05). The oil red O staining results showed that a large amount of lipid accumulation in the liver tissues of the HF group, while the hepatic lipid accumulations of 400 C-MI, 400E-MI and 800 E-MI were significantly reduced (P < 0.05). The expressions of lipid metabolization-related genes showed that the myo-inositol PM and IL had an interactive effect on mRNA expressions of hepatic ACO, ACSL, PPARβ and SIRT1 (P < 0.05). The mRNA expression levels of ACC, AMPK, PPARβ and SREBP-1 were significantly affected by IL (P < 0.05). Specifically, The mRNA expressions of LPL, PPARβ and SIRT1 of 400 C-MI, 400E-MI and 800 E-MI groups were significantly higher than those of the HF basic group. Overall, the supplementation of C-MI and E-MI in the HF diet improved the protein deposition and liver antioxidant ability, promoted lipid metabolism through activating AMPK and SIRT1 of C. Carpio var. jian fed HF diet.

Synergic effect of temperature and alkalinity on the long‐term durability of pure vinyl ester

AbstractThis paper presents an experimental approach to investigate the long‐term durability of vinyl ester (VE) used in civil/structural engineering. Various alkaline (pH = 7, 11, 12, and 13) and temperature (23, 40, and 60°C) conditions were considered for accelerated aging over 12 months. The test results reveal only slight changes in water absorption capacity (0.75–1.17%) and mass loss (~1%) for the aged VE, which can be explained by the unchanged glass transition temperature. Furthermore, significant hydrolysis reaction and severe microcracking at an elevated temperature resulted in a higher diffusion coefficient. The VE diffusion coefficient increases from 6.60 × 10−7 to 1.75 × 10−6 after 12‐month aging in 23°C water (pH = 7), but becomes 4.00 × 10−6 mm2/s as the water temperature rises to 60°C. Surface microcracks with a depth of ~8.46 and chemical hydrolysis reaction with a 74% increment of OH/CH ratio were observed in the 12‐month aged VE at 60°C. However, the diffusion coefficient was insensitive to alkalinity (pH = 7, 11, 12, and 13) regardless of the exposure time and temperatures, which could be attributed to the similar OH/CH ratio at different alkaline conditions. The results of this study shed light on understanding the VE degradation in harsh environments as applied in fiber‐reinforcement polymer (FRP) composites.

Design, synthesis and chemical stability of indolizine derivatives for antidiabetic activity

Prodrugs of metformin were synthesized with the goal of enhancing biological activity of metformin. They were synthesized by combining metformin with 2-substituted indolizine (C7–C12). The synthesized prodrugs were characterized by IR, 1H NMR, 13C NMR, and mass spectroscopy. The chemical hydrolysis of C7–C12 was carried out at pH 1.2, 6.8, and 7.4. All compounds showed encouraging chemical stability at pH 1.2 and 6.8, whereas mild hydrolysis was shown at pH 7.4. Further prodrugs were screened for antidiabetic activity using a streptozotocin-induced model in rat. These derivatives showed substantial results. Among them C8 showed significant activity in the reduction of streptozotocin-induced blood glucose in rats when compared to that of metformin, indicating the effectiveness of prodrug.

Autonomous Chemistry Enabling Environment-Adaptive Electrochemical Energy Storage Devices

Autonomous Chemistry Enabling Environment-Adaptive Electrochemical Energy Storage Devices

Cytotoxic constituents from the leaves and stems of Panax quinquefolius

Four new isolates including one new butanediamide glycoside (1), one new flavonoid glycoside (2) and two new flavonone glycosides (3, 4) were identified from the leaves and stems of Panax quinquefolius, among which 1 possessed the firstly reported N,N'-(5-hydroxy-1,3-phenylene) butanediamide skeleton with an unique 6/9 ranged dual-ring structure. The structures were elucidated by the NMR data, ECD analysis and chemical acid hydrolysis. All the compounds (1-4) were tested for their cytotoxicity against two human cancer cell lines of HepG2, A549 and HCT116 by the MTT method. Outstandingly, compound 1 exhibited targeted inhibitory proliferation of HCT116 cell with IC50 value of 12.1 μM, whereas compounds 3 and 4 exhibited targeted inhibitory proliferation of HepG2 cell with IC50 values of 15.3 and 17.3 μM, as well as no obvious cytotoxicity of compounds 1-4 against A549.

Biological pre-hydrolysis and thermal pretreatment applied for anaerobic digestion improvement: Kinetic study and statistical variable selection

In the present study, two pretreatment methods (thermal pretreatment and biological pre-hydrolysis) were suggested for food waste (FW) with the aim to enhance biomass conversion and biogas production by anaerobic. The effects of thermal pretreatment (TP), including TP at 60 °C and 80 °C for 60 min, and TP at 100 °C, 120 °C and 140 °C for 30 min, well as biological pre-hydrolysis (BPH) at 37 °C, 55 °C, 37 °C followed by 55 °C and 55 °C followed by 37 °C for 40 h on anaerobic digestion performance of FW were evaluated in batch tests. Results were compared with untreated FW. The BPH and TP caused an increase in the soluble chemical oxygen demand and hydrolysis efficiency. The methane yield (MY) increased from 371.17 mL CH4/g VS for untreated FW to 471.95 mL CH4/ g VS. The maximal MY was recorded for BPH at 37 °C for 20 h followed by 55 °C for 20 h. The pretreatments increased the biogas production rate and reduced the lag phase. The most influential variables on the methane yield were investigated using three statistical methods: Principal component analysis, Mutual Information and R-squared. The results allowed a good modeling of the methane yield and minimized the overfitting effect. For reproduction and solid contribution to the field, we have attached to our article all the necessary material to reproduce the same statistical work as in the paper body.

Bioactive peptides-derived from marine by-products: development, health benefits and potential application in biomedicine

Increased fisheries products have raised by-products that are discarded due to low economic value. In addition, marine by-products are still rich in protein and nutritional value that have biological activities and give benefits to human health. Meanwhile, there is raised pressure for sustainability practices in marine industries to reduce waste and minimize the detrimental effect on the environment. Thus, valorization by-products through bioactive peptide mining are crucial. This review focus on various ways to obtain bioactive peptides from marine by-products through protein hydrolysis, for instance chemical hydrolysis (acid and based), biochemical hydrolysis (autolysis and enzymatic hydrolysis), microbial fermentation, and subcritical water hydrolysis. Nevertheless, these processes have benefits and drawbacks which need to be considered. This review also addresses various biological activities that are favorable in pharmaceutical industries, including antioxidant, antihypertensive, anticancer, anti-obesity, and other beneficial bioactivities. In addition, some potential marine resources of Indonesia for the marine biopeptide from their by-product or undesired marine commodities would be addressed as well.

Degradation of Cellulose Derivatives in Laboratory, Man-Made, and Natural Environments.

Biodegradable polymers complement recyclable materials in battling plastic waste because some products are difficult to recycle and some will end up in the environment either because of their application or due to wear of the products. Natural biopolymers, such as cellulose, are inherently biodegradable, but chemical modification typically required for the obtainment of thermoplastic properties, solubility, or other desired material properties can hinder or even prevent the biodegradation process. This Review summarizes current knowledge on the degradation of common cellulose derivatives in different laboratory, natural, and man-made environments. Depending on the environment, the degradation can be solely biodegradation or a combination of several processes, such as chemical and enzymatic hydrolysis, photodegradation, and oxidation. It is clear that the type of modification and especially the degree of substitution are important factors controlling the degradation process of cellulose derivatives in combination with the degradation environment. The big variation of conditions in different environments is also briefly considered as well as the importance of the proper testing environment, characterization of the degradation process, and confirmation of biodegradability. To ensure full sustainability of the new cellulose derivatives under development, the expected end-of-life scenario, whether material recycling or “biological” recycling, should be included as an important design parameter.

Bound phenolics in rice bran dietary fibre released by different chemical hydrolysis methods: content, composition and antioxidant activities

SummaryPhenolics in whole grains naturally occur in free and bound forms, and are dominated by the latter. Previous study indicated that bound phenolics played an indispensable role in the health benefits of whole grain dietary fibre. However, existing extraction methods can only partly release bound phenolics, which results in an underestimation of their contents and activity. The content, composition and antioxidant activity of bound phenolics released from rice bran dietary fibre (RBDF) by different chemical hydrolysis methods were analysed in this study to explore a method releasing much more bound phenolics. The results showed that alkaline hydrolysis could release 1.54 times more phenolics than acid hydrolysis. The combination of 2 hydrolysis methods, especially alkaline‐acid hydrolysis (the residue after alkaline hydrolysis was then hydrolysed with acid), could more effectively release bound phenolics from RBDF. The 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH), oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP) antioxidant activity of the RBDF hydrolysates from different hydrolysis methods were generally consistent with their phenolic contents. However, the alkaline hydrolysate had 7.62% less phenolics, but showed 53.03% higher CAA activity than the acid‐alkaline hydrolysate. The RBDF residues after different chemical hydrolysis, furthermore, exhibited considerable DPPH and FRAP activity by QUENCHER method, indicating their possible local antioxidant activity in the colonic microenviroment.

Polyphenolic Glycosides from the Fruits Extract of Lycium ruthenicum Murr and Their Monoamine Oxidase B Inhibitory and Neuroprotective Activities.

The fruits ofLycium ruthenicum Murr have long been consumed as health food and used in folk medicine in China. Apart from the well-known polysaccharides, the active small molecular constituents in this fruit have not been fully studied. In this work, a systematic phytochemical study was carried out to investigate the small molecules and their potential health benefits. Nine new polyphenolic glycosides, lyciumserin A-I (1-9), together with 16 known compounds (10-25), were isolated and elucidated by high-resolution electrospray ionization mass spectrometry and comprehensive NMR analyses in combination with chemical hydrolysis. Compounds 1, 2, and 16 exhibited moderate inhibitory activity of monoamine oxidase B (MAO-B), while compounds 1 (50 μM) and 2 (100 μM) displayed significant neuroprotective effects (69.22 and 72.38% of cell viability, respectively) in the 6-hydroxydopamine-induced injury of the PC12 cell model (54.41%), comparable to the positive drug rasagiline (70.45%). The neuroprotective effect of 1 and 2 was further evidenced by the observation of the morphological change and fluorescein diacetate/propidium iodide staining. In addition, the levels of the major active compounds (1, 3, 5/6, and 16-18) vary from 21.5 to 892.3 μg/g. This is the first report on phenolic glycosides from the fruits ofL. ruthenicum Murr that possess both significant MAO-B inhibitory and neuroprotective effects, indicating the promising potential of the fruits for the development of health care products and even therapeutic agents for the treatment of Parkinson's disease and other neurodegenerative diseases.

Collagen Extraction from Animal Skin.

Simple SummaryCollagen is useful in many applications including cosmetics, medicine, yarn production and packaging. Collagen can be recovered from skins of animals raised for meat. Here, we review methods for the extraction and purification of collagen from animal skins.Collagen is the most abundant structural protein in animals. It is the major component of skin. It finds uses in cosmetics, medicine, yarn production and packaging. This paper reviews the extraction of collagen from hides of most consumed animals for meat with the focus on literature published since 2000. The different pretreatment and extraction techniques that have been investigated for producing collagen from animal skins are reviewed. Pretreatment by enzymatic, acid or alkaline methods have been used. Extraction by chemical hydrolysis, salt solubilization, enzymatic hydrolysis, ultrasound assisted extraction and other methods are described. Post-extraction purification methods are also explained. This compilation will be useful for anyone wishing to use collagen as a resource and wanting to further improve the extraction and purification methods.

Probing the Structural Details of Chitin Nanocrystal–Water Interfaces by Three‐Dimensional Atomic Force Microscopy

Chitin is one of the most abundant and renewable natural biopolymers. It exists in the form of crystalline microfibrils and is the basic structural building block of many biological materials. Its surface crystalline structure is yet to be reported at the molecular level. Herein, atomic force microscopy (AFM) in combination with molecular dynamics simulations reveals the molecular-scale structural details of the chitin nanocrystal (chitin NC)-water interface. High-resolution AFM images reveal the molecular details of chitin chain arrangements at the surfaces of individual chitin NCs, showing highly ordered, stable crystalline structures almost free of structural defects or disorder. 3D-AFM measurements with submolecular spatial resolution demonstrate that chitin NC surfaces interact strongly with interfacial water molecules creating stable, well-ordered hydration layers. Inhomogeneous encapsulation of the underlying chitin substrate by these hydration layers reflects the chitin NCs' multifaceted surface character with different chain arrangements and molecular packing. These findings provide important insights into chitin NC structures at the molecular level, which is critical for developing the properties of chitin-based nanomaterials. Furthermore, these results will contribute to a better understanding of the chemical and enzymatic hydrolysis of chitin and other native polysaccharides, which is also essential for the enzymatic conversion of biomass.