Design of an antioxidant powder additive based on carvacrol encapsulated into a multilayer chitosan-alginate-maltodextrin emulsion.

Carvacrol has demonstrated antioxidant activity; however, its high volatility and low water solubility limit its direct application in food matrices. Then, an effective encapsulation system is required to protect it. This study aimed to design and characterize a carvacrol-based additive encapsulated in a spray-dried multilayer emulsion based on chitosan/sodium alginate/maltodextrin. Spray-drying temperature of 120 °C and 3 %(w/w) maltodextrin content maximized both encapsulation efficiency (~97 %) and loading capacity (~53 %). The powder's antioxidant properties were evaluated in two food simulant media: water (SiW) and water-ethanol (SiD). The highest antioxidant activity was observed in SiW for both ABTS•+ (8.2 ± 0.3mgEAG/g) and FRAP (4.1 ± 0.2mgEAG/g) methods because of the reduced release of carvacrol in SiD vs. SiW, as supported by micro- and macrostructural observations by SAXS and microscopy, respectively. An increase from 143 to 157 °C attributable to carvacrol protection and Tg = 44.4 °C (> ambient) were obtained by TGA and DSC, respectively. FT-IR confirmed intermolecular interactions (e.g. -COO- and -NH3+) as well as H-bonding formation. High water solubility (81 ± 3 %), low hygroscopicity (8.8 ± 0.2 %(w/w), poor flowability (CI:45 ± 4), and high cohesiveness (HR:1.8 ± 0.1) between particles were achieved, leading to a powdered antioxidant additive with high potential for applications which required avoiding/reducing oxidation on hydrophilic and hydrophobic food products.

Assessment of calcium alginate gels as wall materials for encapsulation systems.

BACKGROUND: Calcium alginate gels are widely used to encapsulate active compounds. Some characteristic parameters of these gels are necessary to describe the release of active compounds through mechanistic mathematical models. In this work, transport and kinetics properties of calcium alginate gels were determined through simple experimental techniques. RESULTS: The weight-average molecular weight ( M ¯ w = 192 × 103 Da) and the fraction of residues of α-l-guluronic acid ( F G = 0.356) of sodium alginate were determined by capillary viscometry and 1 H-nuclear magnetic resonance at 25 °C, respectively. Considering the half egg-box model, both values were used to estimate the molecular weight of calcium alginate as M g = 2.02 × 105 Da. An effective diffusion coefficient of water ( D eff , w = 2.256 × 10-9 m2 s-1 ) in calcium alginate was determined using a diffusion cell at 37 °C. Finally, a kinetics constant of depolymerization ( k m = 9.72 × 10-9 m3 mol-1 s-1 ) of calcium alginate was obtained considering dissolution of calcium to a medium under intestinal conditions. CONCLUSION: The experimental techniques used are simple and easily reproducible. The obtained values may be useful in the design, production, and optimization of the alginate-based delivery systems that require specific release kinetics of the encapsulated active compounds. © 2023 Society of Chemical Industry.

Increased production of chitinase by a Paenibacillus illinoisensis isolated from Brazilian coastal soil when immobilized in alginate beads.

The accumulation of chitin waste from the seafood industry is a serious environmental problem. However, this residue can be degraded by chitinases and its subproducts, such as chitosan, economically exploited. In this study, a chitinase producer bacteria, identified as Paenibacillus illinoisensis, was isolated from the Brazilian coastal city of Terra de Areia - Rio Grande Do Sul (RS) and was immobilized within alginate beads to evaluate its chitinase production. The alginate beads containing cells presented an average size of 4 mm, 99% of immobilization efficiency and increased the enzymatic activity in 40.71% compared to the free cells. The biomass during enzymatic production increased 62.01% and the total cells leaked from the alginate beads corresponded to 6.46% after 96 h. Immobilized cells were reused in a sequential batch system and remained stable for production for up to four 96-h cycles, decreasing only 21.04% of the initial activity at the end of the fourth cycle. Therefore, the methodology used for cell immobilization resulted in adequate beads to maintain cell viability during the enzymatic production, increasing enzymatic activity, showing low cell leakage from the support and appropriate recyclable capacity.

Structural Effects of pH Variation and Calcium Amount on the Microencapsulation of Glutathione in Alginate Polymers.

Reduced glutathione (GSH) has a high antioxidant capacity and is present in nearly every cell in the body, playing important roles in nutrient metabolism, antioxidant defense, and regulation of cellular events. Conversely, alginate is a macromolecule that has been widely used in the food, pharmaceutical, biomedical, and textile industries due to its biocompatibility, biodegradability, nontoxicity, and nonimmunogenicity as well as for its capabilities of retaining water and stabilizing emulsions. The primary goal of this study was to characterize and optimize the formation of a molecular complex of calcium alginate with GSH using a computational approach. As methods, we evaluated the influence of varying the amount of calcium cations at two different pHs on the structural stability of Ca2+-alginate complexes and thus on GSH liberation from these types of nanostructures. The results showed that complex stabilization depends on pH, with the system having a lower Ca2+ amount that produces the major GSH release. The systems at pH 2.5 retain more molecules within the calcium-alginate complex, which release GSH more slowly when embedded in more acidic media. In conclusions, this study demonstrates the dependence of the amount of calcium and the stabilizing effect of pH on the formation and subsequent maintenance of an alginate nanostructure. The results presented in this study can help to develop better methodological frameworks in industries where the release or capture of compounds, such as GSH in this case, depends on the conditions of the alginate nanoparticle.

Molecular weight and guluronic/mannuronic ratio of alginate produced by Azotobacter vinelandii at two bioreactor scales under diazotrophic conditions.

Alginates can be used to elaborate hydrogels, and their properties depend on the molecular weight (MW) and the guluronic (G) and mannuronic (M) composition. In this study, the MW and G/M ratio were evaluated in cultures of Azotobacter vinelandii to 3 and 30 L scales at different oxygen transfer rates (OTRs) under diazotrophic conditions. An increase in the maximum OTR (OTRmax) improved the alginate production, reaching 3.3 ± 0.2 g L-1. In the cultures conducted to an OTR of 10.4 mmol L-1 h-1 (500 rpm), the G/M increased during the cell growth phase and decreased during the stationary phase; whereas, in the cultures at 19.2 mmol L-1 h-1 was constant throughout the cultivation. A higher alginate MW (520 ± 43 kDa) and G/M ratio (0.86 ± 0.01) were obtained in the cultures conducted at 10.4 mmol L-1 h-1. The OTR as a criterion to scale up alginate production allowed to replicate the concentration and the alginate production rate; however, it was not possible reproduce the MW and G/M ratio. Under a similar specific oxygen uptake rate (qO2) (approximately 65 mmol g-1 h-1) the alginate MW was similar (approximately 365 kDa) in both scales. The evidences revealed that the qO2 can be a parameter adequate to produce alginate MW similar in two bioreactor scales. Overall, the results have shown that the alginate composition could be affected by cellular respiration, and from a technological perspective the evidences contribute to the design process based on oxygen consumption to produce alginates defined.

Comparison of acid and enzymatic hydrolysis of pectin, as inexpensive source to cell growth of Cupriavidus necator.

Abstract: The present work investigated what the appropriate methods of hydrolysis of pectin for reducing compounds (RCs) production, employed as a substrate for cell growth of Cupriavidus necator. This microorganism has great importance industrial, because besides potential single cell protein (SCP), is the most studied microorganism for production of polyhydroxybutyrate (PHB), and both processes require high cell concentration with inexpensive substrates For this, it was compared to acid and enzymatic hydrolysis procedures, through rotational central composite experimental design, using pectin concentration (1.0%). It was analyzed as a variable response for both experimental design, the RCs' production. The best conditions of each procedure were used in study kinetics of RCs' production and as a substrate for cell growth of C. necator. The results indicated that the enzymatic hydrolysis method was the most efficient, with a 93.0% yield of RCs, while the yield for acid hydrolysis was 60.0%. The optimum conditions for enzymatic hydrolysis were an enzyme concentration of 10.01 UI/g (International Unit of enzyme per gram of pectin) and an agitation speed of 230.3 rpm. C. necator showed satisfactory growth in the media containing pectin hydrolysates, with specific growth rates (µMax) similar to those reported for other substrates.

Sequential extraction of phenolics and pectin from mango peel assisted by ultrasound.

The present work evaluated the use of ultrasound to extract sequentially phenolics and pectin from mango peel. Initially, the influence of ethanol and ultrasound on the phenolics extraction was investigated. The results showed that the ultrasound did not affect the extraction yield of these compounds. The best total phenolics yield (67%) was obtained with an extraction solution consisting of 50% of ethanol in water (v/v) and without ultrasound application, according to the experimental design. As an innovative extraction methodology, the residue of this extraction was then used to extract pectin assisted by ultrasound. The use of ultrasound increased over than 50% of the pectin extraction yield and did not affect its quality, measured by the galacturonic acid content and the degree of esterification. The sequential extraction of phenolics and pectin shows to be an alternative to use the whole residue from mango peel.

Novel magneto-responsive nanoplatforms based on MnFe2O4 nanoparticles layer-by-layer functionalized with chitosan and sodium alginate for magnetic controlled release of curcumin.

Remotely assisted drug delivery by means of magnetic biopolymeric nanoplatforms has been utilized as an important tool to improve the delivery/release of hydrophobic drugs and to address their low cargo capacity. In this work, MnFe2O4 magnetic nanoparticles (MNPs) were synthesized by thermal decomposition, coated with citrate and then functionalized with the layer-by-layer (LbL) assembly of polyelectrolyte multilayers, with chitosan as polycation and sodium alginate as polyanion. Simultaneous conductimetric and potentiometric titrations were employed to optimize the LbL deposition and to enhance the loading capacity of nanoplatforms for curcumin, a hydrophobic drug used in cancer treatment. ~200 nm sized biopolymer platforms with ~12 nm homogeneously embedded MNPs were obtained and characterized by means of XRD, HRTEM, DLS, TGA, FTIR, XPS and fluorescence spectroscopy techniques to access structural, morphological and surface properties, to probe biopolymer functionalization and to quantify drug-loading. Charge reversals (±30 mV) after each deposition confirmed polyelectrolyte adsorption and a stable LbL assembly. Magnetic interparticle interaction was reduced in the biopolymeric structure, hinting at an optimized performance in magnetic hyperthermia for magneto-assisted drug release applications. Curcumin was encapsulated, resulting in an enhanced payload (~100 µg/mg). Nanocytotoxicity assays showed that the biopolymer capping enhanced the biocompatibility of nanoplatforms, maintaining entrapped curcumin. Our results indicate the potential of synthesized nanoplatforms as an alternative way of remotely delivering/releasing curcumin for medical purposes, upon application of an alternating magnetic field, demonstrating improved efficiency and reduced toxicity.

Blueberry Residue Encapsulation by Ionotropic Gelation.

In the processing of fruits such as blueberry (Vaccinium sp), that has high levels of phenolic acid, the food industry produces tons of organic waste that causes harm to the environment. Encapsulation is a technique used to take advantage of these wastes. Several methods are used to encapsulate substances, among them ionotropic gelation proves to be a simple, precise, efficient and economical method for obtaining particles with encapsulated bioactives. In this manner, the aim of this study was to test sodium alginate as wall material to encapsulate blueberry residue by ionotropic gelation. The microbeads were characterized by scanning electron microscopy (SEM), x-ray diffraction (XRD), total phenolic compounds, antioxidant capacity and in vitro dissolution. The results showed that the microbeads had surface invagination; retention of 67.01% of the phenolic compounds after encapsulation and 68.2%, phenolic release 120 min after in vitro dissolution. The results suggest that the tested matrix was suitable for encapsulation. The produced microbeads are promising for applications in food products, once the phenolic compounds present in the blueberry residues were maintained after encapsulation.

Immobilization of Aspergillus ficuum tannase in calcium alginate beads and its application in the treatment of boldo (Peumus boldus) tea.

Tannase (tannin acyl hydrolase, E.C. 3.1.1.20) is an enzyme that catalyzes the hydrolysis of ester and depside linkages in hydrolysable tannins such as tannic acid, releasing gallic acid and glucose. It has several commercial applications in food industry, among which are gallic acid production, reduction of tannin content in fruit juices, and preparation of instantaneous tea. In this study we immobilized Aspergillus ficuum tannase in calcium alginate beads and then used it to treat boldo (Peumus boldus) tea. Such a technique allowed entrapping tannase with a 75% efficiency and appreciably increasing its thermal and pH stability compared with the free enzyme. Storage stability and reuse of the immobilized enzyme were very promising, in that about 60% of starting enzyme activity was retained after bead storage for 90 days at 4 °C or after six cycles of use. Boldo tea treatment with immobilized tannase for 120 min at 40 °C led to 31 and 60% removals of tannins and epigallocatechin gallate, an increase of about two orders of magnitude in gallic acid content, 56 and 109% increases in total flavonoids and epigallocatechin contents, a 42.8% increase in antioxidant activity and significant enhancements of tea color, clarity and pH.

Alginate-perlite encapsulated Pseudomonas putida A (ATCC 12633) cells: Preparation, characterization and potential use as plant inoculants.

Microbial immobilization can be used to prepare encapsulated inoculants. Here, we characterize and describe the preparation of Ca-alginate-perlite microbeads loaded with cells of plant growth-promoting Pseudomonas putida A (ATCC 12633), for their future application as agricultural inoculants. The microbeads were prepared by dropwise addition of a CaCl2-paraffin emulsion mixture to an emulsion containing alginate 2% (w/v), perlite 0.1-0.4% (w/v) and bacterial suspension in 0.9% NaCl (1010 CFU/mL). For all perlite concentrations used, microbead size was 90-120 µm, the trapped population was 108 CFU/g microbeads and the increase in mechanical stability was proportional to perlite concentration. Microbeads containing 0.4% (w/v) perlite were able to release bacteria into the medium after 30 days of incubation. When we evaluated how P. putida A (ATCC 12633) entrapped in Ca-alginate-perlite (0.4% (w/v)) microbeads colonized the Arabidopsis thaliana rhizosphere, an increase in colonization over time was detected (from an initial 2.1 × 104 to 9.2 × 105 CFU/g soil after 21 days). With this treatment, growth promotion of A. thaliana occurred with an increase in the amount of proteins, and in root and leaf biomass. It was concluded that the microbeads could be applied as possible inoculants, since they provide protection and a controlled release of microorganisms into the rhizosphere.

Thermodynamic and kinetic studies on pectinase extracted from Aspergillus aculeatus: Free and immobilized enzyme entrapped in alginate beads.

The kinetics and thermodynamics of Aspergillus aculeatus pectinase, either free or immobilized in alginate beads, were investigated. Pectinase immobilization ensured an enzyme immobilization yield of 59.71%. The irreversible denaturation of pectinase in both preparations was evaluated at temperatures ranging from 30 to 60 °C. When temperature was raised, the first-order thermal denaturation constant increased from 0.0011 to 0.0231 min-1 for the free enzyme and from 0.0017 to 0.0700 min-1 for the immobilized one, respectively. The results of residual activity tests enabled us to estimate, for denaturation of both free and immobilized pectinase, the activation energy (E⁎d = 85.1 and 101.6 kJ·mol-1), enthalpy (82.59 ≤ ΔH⁎d ≤ 82.34 kJ·mol-1 and 99.11 ≤ ΔH⁎d ≤ 98.86 kJ·mol-1), entropy (-63.26 ≤ ΔS⁎d ≤ -63.85 J·mol-1·K-1 and -5.50 ≤ ΔS⁎d ≤ -5.23 J·mol-1·K-1) and Gibbs free energy (101.8 ≤ ΔG⁎d ≤ 104.7 kJ·mol-1 and 100.6 ≤ ΔG⁎d ≤ 102.0 kJ·mol-1). The integral activity of a continuous system using the free and immobilized enzyme was also predicted, whose results indicated a satisfactory enzyme long-term thermostability in both preparations at temperatures commonly used to clarify juice. These results suggest that both free and immobilized pectinase from A. aculeatus may be profitably exploited in future food industrial applications, with special concern to the immobilized enzyme because of its reusability.

Magnetic hydrogels for levodopa release and cell stimulation triggered by external magnetic field.

Magnetic responsive hydrogels composed of alginate (Alg) and xanthan gum (XG), crosslinked with Ca2+ ions, were modified by in situ magnetic nanoparticles (MNP) formation. In comparison to magnetic Alg hydrogels, magnetic Alg-XG hydrogels presented superior mechanical and swelling properties, due to the high charge density and molecular weight of XG. The loading efficiency of levodopa (LD), an important antiparkinson drug, in the Alg-XG/MNP hydrogels was the highest (64%), followed by Alg/MNP (56%), Alg-XG (53%) and Alg (28%). A static external magnetic field (EMF) of 0.4 T stimulated the release of LD from Alg-XG/MNP hydrogels achieving 64 ±â€¯6% of the initial loading after 30 h. The viability, proliferation and expression of dopaminergic markers of human neuroblastoma SH-SY5Y cell on the LD loaded magnetic hydrogels were successful, particularly under EMF, which stimulated the release of LD. Overall, the results of this study provided the rational design of magnetic hydrogels for the delivery of drugs, which combined with external magnetic stimulus, might improve cell proliferation and specific differentiation.

Polyelectrolyte complex of Aloe vera, chitosan, and alginate produced fibroblast and lymphocyte viabilities and migration.

Chitosan, sodium alginate and gel of Aloe vera (Aloe barbadensis Miller) were employed for the preparation of polyelectrolyte complexes at pH 4 and 6. FT-IR spectroscopy analysis showed evidence on complexes formation and incorporation of the Aloe vera gel. The ζ potential determination of the polyelectrolyte complexes revealed the presence of surface charges in the range of -20 to -24 mV, which results in stable systems. The dynamic moduli exhibited a high dependence on angular frequency, which is commonly found in solutions of macromolecules. The materials showed human fibroblast and lymphocyte viabilities up to 90% in agreement with null cytotoxicity. The polyelectrolyte complexes at pH 6 with Ca2+ were stable, showed high water absorption, satisfactory morphology, pore size and rigidity, characteristics that allowed significant human fibroblast migration in wound closure in vitro assays.

Control of the adsorption properties of alginate - guar gum matrix functionalized with epichlorohydrin through the addition of different flexible chain polymers as toll for the chymotrypsinogen isolation.

This work addresses the obtaining and characterization of alginate-guar gum matrix, cross-linked with epichlorohydrin in the presence of different flexible chain polymers: polyvinyl alcohol, polyvinyl pyrrolidine and Pluronic® F68. These matrixes were used for the adsorption of chymotrypsinogen and showed an increasing uptake in presence of the flexible chain polymer in the sense: none < Pluronic 68 < polyvinyl pyrrolidine < polyvinyl alcohol. The adsorption process was found to follow a first order kinetics model and was not influenced by the polymer type. It was found that Freundlich model was more suitable for our data. Polyvinyl alcohol and polyvinyl pyrrolidine addition increase the adsorption capacity of the original bed due to an increment in the rigidity of the gel caused by the formation of hydrogen bound between the polysaccharides and synthetics polymers.

Properties of microparticles from a whey protein isolate/alginate emulsion gel.

Designing soft, palatable and nutritious texture-modified foods for the elderly is a challenge for food technologists. The aim of this work was to produce and characterize emulsion-gelled microparticles (EGM) made from whey protein isolate (WPI) and sodium alginate (NaAlg) that may be used to modify the rheology of liquid foods and as carriers of lipids and lipophilic nutrients and bioactives. Olive oil microdroplets became embedded in the WPI/NaAlg gel matrix in the form of an emulsion produced by ultrasound (US) or high-speed blending (HSB). Oil microdroplets were obtained by US and HSB, with an average equivalent diameter varying between 2.0-3.2 µm and 4.5-6.7 µm, respectively. Oil incorporation increased compression stress of bulk emulsion gels at small deformations compared to the no-oil microgel, but this effect was reversed at high strains. EGM were prepared by shear-induced size reduction. Rheological tests at 20 ℃ and 40 ℃ showed that US-EGM and HSB-EGM exhibited a predominant elastic behavior, with G' > G″ throughout the frequency range. However, when HSB-EGM were heated at 60 ℃ their rheological behavior changed to a more fluid-like condition, but not that of US-EGM. Consequently, EGM have the properties needed to improve food texture for people with masticatory/swallowing dysfunctions or needing special nutrition.

Degradation of cationic surfactants using immobilized bacteria: Its effect on adsorption to activated sludge.

Adsorption of cationic surfactants (QACs) Br-tetradecyltrimethylammonium (TTAB), Cl-tetradecylbenzyldimethylammonium (C14BDMA) and Cl-hexadecylbenzyldimethylammonium (C16BDMA) to activated sludge from a wastewater treatment plant was tested. Adsorption equilibrium was reached after 2 h, and for initial 200 mg L-1 81%, 90% and 98% of TTAB, C14BDMA and C16BDMA were respectively adsorbed. After six successive desorption cycles, 21% of TTAB and 12.7% of C14BDMA were desorbed from the sludge. In agreement with the percentage of QACs pre-adsorbed, the more hydrophobic the compound, the lesser the extent of desorption. Wastewater samples with activated sludge were supplemented with TTAB 200 mg L-1 and Ca-alginate beads containing the QACs-degrading microorganisms Pseudomonas putida A (ATCC 12633) and Aeromonas hydrophila MFB03. After 24 h, 10 mg L-1 of TTAB were detected in the liquid phase and 6-8 mg L-1 adsorbed to the sludge. Since without Ca-alginate beads or with empty beads total TTAB amount (phase solid and liquid) did not change, the 90% reduction of the initial 200 mg L-1 after treatment with immobilized cells was attributed to the bacterial consortium's capacity to biodegrade QACs. The results show the advantages of using immobilized bacteria to achieve complete QACs elimination from wastewater systems, thus preventing them from reaching the environment.

Optimization of pectin extraction from Ubá mango peel through surface response methodology.

A central composite design was used to determine effects of pH (1.16-2.84), extraction temperature (63-97°C) and time (35-85min) on the yield, degree of degree of esterification (DE) and viscosity of pectins extracted. For pectin extraction, the previously sanitized mango shells were dried and crushed to obtain the flour that was treated with an ethanol solution obtaining the alcohol insoluble residue (AIR). Subsequently, the AIR was mixed in ethanol with the extraction solution of hydrochloric acid. Pectin yields ranged from 18.8 to 32.1g/100g of AIR, whereas the degree of esterification (DE) and viscosity values ranged from 62.2 to 86.2% and from 1.58 to 45.85mPa·s, respectively. An inverse correlation was found between extraction yield and viscosity. Relying upon the desirability function, two optimum conditions were determined: 35min30% from the AIR, DE≥70.0% and η≥20.0mPa·s.

Microbicidal gentamicin-alginate hydrogels.

Sodium alginate (Alg) reacted with antibiotic gentamicin sulfate (GS) in an aqueous-phase condition mediated by carbodiimide chemistry, in the molar ratios Alg: GS of (1:0.5), (1:1) and (1:2). The Alg-GS conjugated derivatives were characterized by elemental analysis for nitrogen content, Fourier transform infrared spectroscopy in the attenuated total reflection mode (FTIR-ATR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), thermogravimetric analyses (TGA) and water sorption measurements. XPS and FTIR-ATR analyses clearly indicated that GS molecules covalently attached to the backbone of the alginate chains by amide bond formation. The highest amount of GS bound to Alg (43.5 ±â€¯0.4 wt%) and the highest swelling ratio (4962 ±â€¯661%) were observed for the Alg-GS (1:2) sample. Bioluminescence assays with Pseudomonas aeruginosa PAO1/lecA:lux and colony forming counting of Staphylococcus aureus and Escherichia coli upon contact with all Alg-GS conjugates revealed microbicidal activity; however, Alg-GS (1:2) was the most efficient, due to the highest GS content.

Alveolar bone repair with strontium- containing nanostructured carbonated hydroxyapatite.

This study aimed to evaluate bone repair in rat dental sockets after implanting nanostructured carbonated hydroxyapatite/sodium alginate (CHA) and nanostructured carbonated hydroxyapatite/sodium alginate containing 5% strontium microspheres (SrCHA) as bone substitute materials. Twenty male Wistar rats were randomly divided into two experimental groups: CHA and SrCHA (n=5/period/group). After one and 6 weeks of extraction of the right maxillary central incisor and biomaterial implantation, 5 µm bone blocks were obtained for histomorphometric evaluation. The parameters evaluated were remaining biomaterial, loose connective tissue and newly formed bone in a standard area. Statistical analysis was performed by Mann-Withney and and Wilcoxon tests at 95% level of significance. The histomorphometric results showed that the microspheres showed similar fragmentation and bio-absorbation (p>0.05). We observed the formation of new bones in both groups during the same experimental periods; however, the new bone formation differed significantly between the weeks 1 and 6 (p=0.0039) in both groups. The CHA and SrCHA biomaterials were biocompatible, osteoconductive and bioabsorbable, indicating their great potential for clinical use as bone substitutes.