Free Amino Groups Research Articles

Effects of Pineapple Peel Ethanolic Extract on the Physicochemical and Textural Properties of Surimi Prepared from Silver Carp (Hypophthalmichthys molitrix)

The effects of ethanolic pineapple peel extract (PPE) powder at various concentrations (0–1.50%, w/w) on the gelling properties of silver carp surimi were investigated. The pineapple peel extract produced with 0–100% ethanol, revealed that 100% ethanol had the highest bioactive properties. Surimi gels with added PPE powder demonstrated improved gel strength (504.13 ± 11.78 g.cm) and breaking force (511.64 ± 11.80 g) up to 1% PPE addition; however, as PPE concentration increased beyond 1%, the gel strength decreased. Similarly, with the addition of 1% PPE powder, more hydrophobic bonds and fewer sulfhydryl groups and free amino groups were seen. However, the gels with PPE powder added showed a slight reduction in the whiteness of the surimi gels. FTIR analysis indicated that the fortification with PPE powder brought about the secondary structure of myofibrillar proteins; peaks shifted to the β-sheet region (PPE gels) from the α-helix region (control). SEM analysis indicated that the gel with 1% PPE powder had a relatively organized, finer and denser gel architecture. Overall results suggested that the addition of PPE powder up to 1% to the surimi gels enhanced the gelling properties as well as the microstructure of the surimi.

Soy protein–phlorizin conjugate prepared by tyrosinase catalysis: Identification of covalent binding sites and alterations in protein structure and functionality

Tyrosinase-catalyzed synthesis of soy 7S/11S–phlorizin conjugates was performed, and the reaction sites, conformation alterations and functional properties of complexes were evaluated using proteomic, in combination with multispectral technologies. Phlorizin was conjugated to 7S/11S primarily via residues of Lys, Cys, His and Arg residues. The phlorizin binding equivalents and decreased contents of free and total sulfhydryl groups and free amino groups confirmed the covalent interaction in the 7S/11S–phlorizin complexes. Conjugation with phlorizin promoted the conversion of α-helix to β-sheet and β-turn, with simultaneous transformation of the microenvironments around Trp and Tyr residues to hydrophilic and hydrophobic microenvironments, respectively, and lowering of the surface hydrophobicity of 7S/11S. The DPPH and ABTS radical scavenging abilities and α-glucosidase inhibitory activities of 7S/11S were increased by three–, two– and three–fold after the covalent binding of phlorizin. The study provided an ideal tyrosinase-catalyzed approach to fabricate custom–tailored nutritional soy protein–polyphenol products.

A highly active esterase from Lactobacillus helveticus hydrolyzes chlorogenic acid in sunflower meal to prevent chlorogenic acid induced greening in sunflower protein isolates

Chlorogenic acid (CGA) is an ester between caffeic and quinic acid. It is found in many foods and reacts with free amino groups in proteins at alkaline pH, leading to the formation of an undesirable green pigment in sunflower seed-derived ingredients. This paper presents the biochemical characterization and application of a highly active chlorogenic acid esterase from Lactobacillus helveticus. The enzyme is one of the most active CGA esterases known to date with a Km of 0.090 mM and a kcat of 82.1 s−1. The CGA esterase is easily expressed recombinantly in E. coli in large yields and is stable over a wide range of pH and temperatures. We characterized CGA esterase’s kinetic properties in sunflower meal and demonstrated that the enzyme completely hydrolyzes CGA in the meal. Finally, we showed that CGA esterase treatment of sunflower seed meal enables the production of pale brown sunflower protein isolates using alkaline extraction. This work will allow for more widespread use of sunflower-derived products in applications where neutrally-colored food products are desired.

1,4,6,10-Tetraazaadamantanes (TAADs) with N-amino groups: synthesis and formation of boron chelates and host-guest complexes.

A synthetic route to 1,4,6,10-tetraazaadamantanes (TAADs) bearing free and protected amino groups at the bridge N-atoms has been developed via intramolecular cyclotrimerization of C=N units in the corresponding tris(hydrazonoalkyl)amines. In a similar fashion, unsymmetrically substituted TAADs having both amino and hydroxy groups at the bridge N-atoms were prepared via a hitherto unknown co-trimerization of oxime and hydrazone groups. The use of N-TAAD derivatives as potential ligands and receptors was showcased through forming boron chelates and host–guest complexes with water and simple alcohols.

Seaweed Slurry Improved Gel Properties and Enhanced Protein Structure of Silver Carp (Hypophthalmichthys molitrix) Surimi.

In order to improve the gel quality of silver carp (Hypophthalmichthys molitrix) surimi, the texture and rheological properties and microstructure of silver carp surimi gel products were analyzed by adding Laminaria japonica (LJ), Undaria pinnatifida (UP) and Sargassum fusiforme (SF) slurries. After adding kelp slurry (KS), the gel strength reached the highest level of 1047.26 ± 85.04 (g·mm). The carbonyl content and surface hydrophobicity of surimi protein increased, while the free amino groups, total sulfhydryl groups, and fluorescence intensity decreased significantly. The results of transform infrared spectroscopy (FT-IR), circular dichroic (CD), and Raman spectra showed that the KS promoted the change of the secondary structure of protein. Scanning electron microscopy (SEM) images revealed that kelp slurry had a more compact gel microstructure. In conclusion, the kelp slurry could significantly increase the gel strength, improve the quality of surimi products, enrich the nutrition of silver carp surimi, and have great significance for expanding the application range of seaweed.

Facile Synthesis of Copper‐5‐Aminoisophthalic Acid Metal Organic Framework as a Potential Drug Carrier for Ibuprofen

AbstractDue to their large surface area and porous nature, metal organic frameworks hold a promising application in drug delivery. Among several combinations of metals with organic linkers, copper as a metal possesses synergistic behavior in drug delivery due to its antibacterial, antioxidant properties, and other biological functional necessities. This study uses the copper‐5‐aminoisophthalic acid metal organic framework (AIPA‐Cu (II) MOF) for drug delivery. From the experimental studies, AIPA‐Cu (II) MOF exhibited a potentially good loading capacity of Ibuprofen drug and excellent controlled release in in‐vitro drug release studies. The loading efficiency of Ibuprofen in AIPA‐Cu (II) MOF has been confirmed using BET adsorption, X‐Ray Diffraction, XPS spectroscopy, UV‐Visible Spectroscopy, and IR spectroscopy by comparing it against unloaded AIPA‐Cu (II) MOF. The uncoordinated free amino group in the 5‐aminoisophthalic acid ligand is expected to form an interaction between Ibuprofen and AIPA‐Cu (II) MOF through van der Waals force to induce better loading. Thus, the current study opens up a new avenue for the potential usage of AIPA‐Cu (II) MOF as an effective and compatible drug carrier for hydrophobic drugs like Ibuprofen.

Improving ACE inhibitory activity of hazelnut peptide modified by plastein: Physicochemical properties and action mechanism

The plastein reaction can increase the activity of angiotensin-converting enzyme (ACE) inhibitory peptides, but the underlying mechanism is unknown. Hence, hazelnut protein hydrolysate and hazelnut peptide YLVR were used as substrate to explore the effect of plastein on physicochemical properties and the mechanism of structural change. The increase in turbidity and particle size and the decrease in free amino groups indicated that the reaction occurred via condensation. The modified products of YLVR were identified by NANO-HPLC-MS/MS, indicating that the N-terminal homologous amino acid aggregates in the plastein. Novel ACE inhibitory peptide YYLVR, YLLVR, and YYLLVR were synthesized and their inhibition rates were 66.35, 72.61, and 89.10 %, respectively, which were higher than that of YLVR (52.58 %). MD simulation showed that YYLLVR exhibited the lowest binding energies of −35.98 ± 2.30 kcal/mol to ACE. Taken together, plastein reaction is a promising strategy for inducing structural modifications to improve the activity of peptide.

The OSE complotype and its clinical potential.

Cellular death, aging, and tissue damage trigger inflammation that leads to enzymatic and non-enzymatic lipid peroxidation of polyunsaturated fatty acids present on cellular membranes and lipoproteins. This results in the generation of highly reactive degradation products, such as malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), that covalently modify free amino groups of proteins and lipids in their vicinity. These newly generated neoepitopes represent a unique set of damage-associated molecular patterns (DAMPs) associated with oxidative stress termed oxidation-specific epitopes (OSEs). OSEs are enriched on oxidized lipoproteins, microvesicles, and dying cells, and can trigger sterile inflammation. Therefore, prompt recognition and removal of OSEs is required to maintain the homeostatic balance. This is partially achieved by various humoral components of the innate immune system, such as natural IgM antibodies, pentraxins and complement components that not only bind OSEs but in some cases modulate their pro-inflammatory potential. Natural IgM antibodies are potent complement activators, and 30% of them recognize OSEs such as oxidized phosphocholine (OxPC-), 4-HNE-, and MDA-epitopes. Furthermore, OxPC-epitopes can bind the complement-activating pentraxin C-reactive protein, while MDA-epitopes are bound by C1q, C3a, complement factor H (CFH), and complement factor H-related proteins 1, 3, 5 (FHR-1, FHR-3, FHR-5). In addition, CFH and FHR-3 are recruited to 2-(ω-carboxyethyl)pyrrole (CEP), and full-length CFH also possesses the ability to attenuate 4-HNE-induced oxidative stress. Consequently, alterations in the innate humoral defense against OSEs predispose to the development of diseases associated with oxidative stress, as shown for the prototypical OSE, MDA-epitopes. In this mini-review, we focus on the mechanisms of the accumulation of OSEs, the pathophysiological consequences, and the interactions between different OSEs and complement components. Additionally, we will discuss the clinical potential of genetic variants in OSE-recognizing complement proteins – the OSE complotype - in the risk estimation of diseases associated with oxidative stress.

Oxidative stability and gelation properties of myofibrillar protein from chicken breast after post-mortem frozen storage as influenced by phenolic compound-pterostilbene

The aim of this study was to elucidate the effects of dietary pterostilbene supplementation on physicochemical changes and gel properties of myofibrillar protein (MP) in chicken when subjected to short-term frozen storage. The results showed that pterostilbene supplementation diminished the oxidation of MP compared to the control, as the carbonyl content was significantly reduced and the loss of sulfhydryl and free amino groups was slowed. Meanwhile, the surface hydrophobicity and insolubility of MP were significantly reduced. FT-IR and endogenous fluorescence spectroscopy analysis indicated that dietary pterostilbene inhibited the unfolding of protein structure and the transition of α-helix to β-sheet structure. The integrity of the protein structure contributed to the gel quality. The strength, whiteness and water-holding capacity (WHC) of MP gels were improved in the pterostilbene treatment group. In terms of microstructure, pterostilbene facilitated the formation of dense and homogeneous gel network structure. In summary, these findings suggest that pterostilbene could be used as a dietary supplement to maintain the structural stability of MP in postmortem chicken breast muscle, allowing for excellent gel functional properties.

Optimization of enzymatic soy protein isolate-glucosamine conjugates to improve the freeze-thaw stability of emulsion.

Using transglutaminase (TGase) is a new method to improve protein properties in order to promote protein glycosylation. This article mainly studies soy protein isolate (SPI) and glucosamine to improve the freeze-thaw stability of emulsion under the action of TGase. The degree of glycosylation was studied by the content of free amino groups and the degree of conjugation. The optimal conditions for preparing soy protein isolate-glucosamine (SPI-G) conjugate were determined by a response surface optimization model based on single-factor experiments using the creaming index of the emulsion after the first freeze-thaw cycle as the response value. The results showed that the emulsion had the lowest creaming index when the conditions of protein concentration was 20 g L-1 , mass ratio of SPI-G was 5:3 (w/w), enzyme addition amount was 10U g-1 , and reaction time was 2h. The optimized modified product was measured for the creaming index after the first freeze-thaw cycle. It was found that the creaming index of the modified product SPI-G after the first freeze-thaw cycle was 9.02%, which was less than and close to the optimized model predicted value. The creaming index and optical microscopy results after three freeze-thaw cycles confirmed that the freeze-thaw stability of the SPI-G samples was significantly enhanced after optimization of the response surface model. It showed that glycosylation promoted by TGase could improve the freeze-thaw stability of SPI emulsion, thereby broadening the application of SPI in food. © 2022 Society of Chemical Industry.

The effects of conjugation of walnut protein isolate with polyphenols on protein solubility, antioxidant activity, and emulsifying properties

Alkaline-extracted walnut protein isolate (AWPI) shows poor solubility in aqueous solutions, resulting in relatively low emulsion capacity. This work investigated the influence of ellagic acid (EA) or epigallocatechin-3-gallate (EGCG) conjugation on the solubility and emulsifying properties of AWPI. The increase in polyphenol content and decrease in free amino and thiol groups of walnut proteins confirmed successful conjugation. AWPI polyphenol conjugates showed significantly reduced surface hydrophobicity, greatly enhanced surface charge, and consequently improved solubility. Circular dichroism (CD) results indicated that the polyphenol-conjugated AWPI contained relatively higher α-helical and lower β-sheet contents than AWPI. The antioxidant capacity of the polyphenol-conjugated AWPI was significantly enhanced. Additionally, polyphenol conjugation resulted in decreased mean particle sizes and increased surface charges of the walnut protein-covered oil droplets. The emulsions stabilized by AWPI-polyphenol conjugates were relatively more stable over a range of pH values (7.0–11.0) and thermal treatments (25 °C–90 °C). Moreover, they exhibited greater storage stability than those stabilized by unmodified AWPI.

Development of signal multiplication system for quinone linked immunosorbent assay (Multi-QuLISA) by using poly-l-lysine dendrigraft and 1,2-naphthoquinone-4-sulfonate as enzyme-free tag

A sensitive and stable signal multiplied quinone-linked immunosorbent assay (Multi-QuLISA) was developed. In Multi-QuLISA, an oligomerized quinone linked to biotin, namely biotin-8mer-naphthoquinone (Bio8mer-NQ), is used as a signal-generating label. Bio8mer-NQ is formed from a dendrigraft poly-l-lysine generation 1 (DPLL G1), a controlled branched oligomer composed of eight lysine moieties with nine free amino groups as a backbone. One of the nine amino groups of DPLL G1 is attached to biotin moiety, while the other eight are attached to 1,2-naphthoquinone-4-sulfonate (NQS). Bio8mer-NQ labels a biotinylated detection antibody using avidin as a co-binder. Then, multi-quinones in Bio8mer-NQ undergo a redox cycle with dithiothreitol and luminol, generating strong chemiluminescence. Standard ELISA uses a label enzyme that suffers from vulnerability in different conditions and poor stability. Bio8mer-NQ showed better stability than the enzyme (biotin-HRP) under different drastic pH and temperature conditions, hydrolytic enzymes, etc. Furthermore, Bio8mer-NQ was used as both chemiluminescence and colorimetric label based on the redox cycle of quinone, and it had LODs of 1.5 and 6.5 nM, respectively. The method could detect biotinylated immunocomplex in an in-house designed immunoassay down to 0.2 nM, which is about 25 times more sensitive than biotin HRP. Eventually, Bio8mer-NQ was applied successfully in Multi-QuLISA for detecting β-casein with a sensitivity of 3.2 ng/mL, while the conventional ELISA had an LOD of 35 ng/mL. Overall, Bio8mer-NQ is a stable compound that could be used as an excellent replacement for the enzyme in immunoassay and can be used in both colorimetric and chemiluminescence assays with good sensitivity.

Variation of in vitro digestibility of pea protein powder dispersions from commercially available sources

With raising consumer demand for plant-derived proteins, there has been an increased interest in the utilization of pea ingredients in food formulations. It was hypothesized that differences in processing history and composition affect their colloidal properties and their breakdown during in vitro simulated gastrointestinal digestion. The gastrointestinal fate of three different commercial pea protein ingredients, two protein isolates and one less refined concentrate was compared. The concentrate dispersion showed greater solubility, different protein composition and smaller particle size than the reconstituted pea protein isolates. When heat-treated, the release of free amino groups decreased for the isolates, but increased for the concentrate dispersions. LC-TQMS of free amino acids in the intestinal digestates indicated a significantly higher release of methionine (limiting amino acid in pea protein) in the concentrates than in the isolates. This work highlights the influence of processing and composition on techno-functional and digestion properties of pea ingredients.

Postsynthetic Modification of Ti-Based Metal–Organic Frameworks with Polyamines and Its Behavior on Biochemical Constituents of Sesamum indicum L. under Heat Stress Conditions

Climate change can affect the characteristics of various crops, such as biomass production, phenology, and physiology. Heat stress is one of the critical environmental factors for climate change; here, Sesamum indicum L. was planted in the field under heat stress of El-Wadi El-Gedeed conditions. To overcome the loss in seed yield and oil contents, the titanium–organic framework (MIL-125-NH2) can be modified with a free amino group in the network backbone using polyamines such as putrescine (Put), spermidine (Spd), and spermine (Spr) through a cross-linker with the phosphoryl group. The modified materials were sprayed on the vegetative part of S. indicum L., and the obtained results showed that the prepared materials have excellent performance toward growth parameters, added chemical components, and crop yield. The weight of sesame seeds obtained after treatment with Put@MIL-125-NH2, Spr@MIL-125-NH2, and Spd@MIL-125-NH2 showed an increase that is 1.39, 1.92, and 2.16 times that of the control experiment. The finding results support sustainable modern agriculture.

Evaluation of the effect of sage seed gum (Salvia macrosiphon) conjugation on physicochemical and antimicrobial properties of egg white protein

SummarySage seed gum (SSG), a galactomannan hydrocolloid, possesses excellent thickening, stabilising and antimicrobial properties. This study aimed to investigate the effect of SSG conjugation on the functional, antimicrobial and antioxidant properties of EWP. EWP‐SSG conjugates were prepared by dry heat treatment of EWP‐SSG mixture at 60 °C and 79% relative humidity for 3‐, 5‐, 7‐ and 10‐day incubation. Interaction of reducing‐end SSG with amino groups of EWP was confirmed by melanoidin compounds content, free amino groups (FAG), Fourier transform infrared (FT‐IR), sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS‐PAGE) and scanning electron microscopy (SEM). The results indicated solubility, foaming capacity, foaming stability, emulsification activity index and emulsification stability index remarkably increased after 5 days of incubation. Conjugation led to enhanced antimicrobial activity in 10‐day conjugated samples, so higher antibacterial activity against Bacillus cereus and Staphylococcus aureus was obtained compared with antibiotic disc. Comparison of emulsions (O/W) stabilised by 5‐day conjugate, EWP‐SSG mixture and unmodified EWP revealed better physical stability behaviour in 5‐day conjugate against ionic, pH and thermal stresses, suggesting its potential application in different food processing conditions. The findings showed dry heat‐treated SSG‐EWP conjugate could enhance the functional, antioxidant and antimicrobial properties of EWP.

Amino-Functionalized Single-Lanthanide Metal–Organic Framework as a Ratiometric Fluorescent Sensor for Quantitative Visual Detection of Fluoride Ions

Excessive content of fluoride ions (F-) in water will lead to water pollution and endanger human health, so the research on the method of low-cost, rapid, and efficient detection of F- is of particular significance. In this work, an amino-functionalized ligand with an appropriate triplet energy excited state, 2'-amino-[1,1':4',1″-terphenyl]-3,3″,5,5″-tetracarboxylic acid (H4TPTC-NH2), was selected to construct a luminescent single-lanthanide metal-organic framework, EuTPTC-NH2, with uncoordinated amino groups for the detection of F-. Based on host-guest interactions, that is, hydrogen bonds formed between the free amino groups and F- ions, EuTPTC-NH2 was developed as a ratiometric fluorescence probe for F- detection with good anti-interference ability, low detection limit, high water stability, and selectivity. It was found that EuTPTC-NH2 has an excellent linear response to F- in the concentration range of 0-80 μM with high sensitivity and a low detection limit of 11.26 μM. A hydrogel membrane based on the combination of EuTPTC-NH2 and agarose was also prepared for the quantitative visual detection of F- in water.

Antioxidant and antiglycation activities and inhibitory action of Passiflora cincinnata on collagenase, elastase and tyrosinase: in vitro and in silico study

Passiflora species are widely used in folk medicine due to their sedative and anxiolytic activities; however, scientific studies also showed different biological activities (antioxidant, anti-inflammatory, antidiabetic and antimicrobial). The present study aimed to characterize the phytochemical profile of P. cincinnata hydroethanolic extract, evaluate its antioxidant and antiglycation activities and evaluate in silico molecular docking of its main flavonoids. Phytochemical characterization was performed by quantification of total polyphenols and flavonoids content, and High Performance Liquid Chromatography-Mass Spectrometry (HPLC-MS) analysis. Antioxidant activity was determined by 2,2-Diphenyl-1-picrylhydrazyl (DPPH), Ferric reducing antioxidant power (FRAP), Nitric oxide (NO) and Thiobarbituric acid reactive species (TBARS) tests. Antiglycation activity was determined by Relative Electrophoretic Mobility (REM) and free amino groups assays. P. cincinnata presented total polyphenols (62 mg gallic acid equivalent (GAE) g−1 dry weight (DW)) and flavonoids (57 mg rutin equivalent (RE) g−1 DW), besides HPLC-MS showed the presence of different flavonoids glucoside, mainly vitexin and orientin. The extract presented antioxidant activity by DPPH (76.60%), FRAP (276.70 μM trolox equivalent (TE) g−1 DW), TBARS (80.30% inhibition) and NO (10.10 μM mL−1 nitrite formed). REM demonstrated that extract presents antiglycation activity similar to Bovine serum albumin treated with Aminoguanidine; additionally, it showed 22% free amino groups. In silico assay demonstrated that orientin exhibited the highest interaction with DNA and the best docking score with elastase and collagenase. Therefore, the present study showed the protective properties of P. cincinnata hydroethanolic extract against oxidative stress and glycation. It also showed the presence of polyphenols and flavonoids, and their interaction with DNA and enzymes.

Changes in protein oxidation, structure, and thermal stability of chicken breast subjected to ultrasound-assisted immersion freezing during frozen storage

The influence of ultrasound-assisted immersion freezing (UF), immersion freezing (IF), and air freezing (AF) on the protein oxidation, structure, and thermal stability of chicken breast during frozen storage was evaluated in this study. Compared to IF and AF samples, the UF samples had a lower carbonyl content, dityrosine content, and surface hydrophobicity of myofibrillar protein (MP) (P < 0.05), as well as a higher free amino group content and total and reactive sulfhydryl content (P < 0.05). Moreover, UF significantly delayed the deterioration of protein secondary and tertiary structures and the decrease in protein thermal stability during frozen storage (P < 0.05). Additionally, the UF samples at 180 days had similar protein structures and quality characteristics to the IF samples at 90 days or the AF samples at 60 days. Overall, UF treatment can effectively retard protein oxidation, protein structure deterioration, and protein thermal stability loss caused by frozen storage.

Synthesis and Biological Activity Characterization of Novel 5-Oxopyrrolidine Derivatives with Promising Anticancer and Antimicrobial Activity.

The 1-(4-acetamidophenyl)-5-oxopyrrolidine carboxylic acid was applied for synthesizing derivatives bearing azole, diazole, and hydrazone moieties in the molecule. Modification of an acetamide fragment to the free amino group afforded compounds with two functional groups, which enabled to provide a series of 4-substituted-1-(4-substituted phenyl)pyrrolidine-2-ones. The resulted compounds 2 and 4–22 were subjected to the in vitro anticancer and antimicrobial activity determination. The compounds 18–22 exerted the most potent anticancer activity against A549 cells. Furthermore, compound 21 bearing 5-nitrothiophene substituents demonstrated promising and selective antimicrobial activity against multidrug-resistant Staphylococcus aureus strains, including linezolid and tedizolid-resistant S. aureus. These results demonstrate that 5-oxopyrolidine derivatives are attractive scaffolds for the further development of anticancer and antimicrobial compounds targeting multidrug-resistant Gram-positive pathogens.

Silica-based fibers with axially aligned mesopores from chitin self-assembly and sol-gel chemistry

Polysaccharide nanorods (chitin, cellulose) can be used as colloidal templates to form silica-based mesoporous materials by combining self-assembly and sol-gel chemistry. Chitin nanorods are chosen here for their self-assembly properties, facile preparation from natural resources, and because of the complexing properties of the free amino groups at their surface in view of further functionalization. Electrospinning of ethanolic co-suspensions, containing the chitin nanorods as pore templates, siloxane oligomers as silica precursors and polyvinylpyrrolidone (PVP) as spinning polymer, allows for forming mats of hybrid organic-inorganic fibers with diameters in the 200–300 nm range. The relative proportions of each component can be adjusted to meet specific characteristics (e.g. micro-/mesoporosity ratio). After calcination, the fibers present an open porosity studied by TEM and N2 volumetry. Elongated mesopores (100–200 nm long, 2–4 nm wide) are created by individual chitin monocrystals forming the nanorods. They are highly oriented along the fibers' axes with orientational order parameters P2 > 0.95 for volume chitin contents φchitin* ≥ 0.2. Additional microporosity is provided by the removal of the spinning polymer, PVP. Complementary viscosity measurements on the initial co-suspensions allow discussing the interactions between colloids and their possible impact on the materials’ textures observed. The introduction of a monomeric Ti4+ precursor in the co-suspensions leads to isolated and tetrahedral Ti units, distributed in the calcined porous silica fibers and possibly close to the pores surface. In addition, preliminary investigations on processing the fibers with a Zn xanthate as ZnS precursor leads to carbonized fibers with nanoparticles and a Zn/S molar ratio close to 1.