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1.
Food Sci Anim Resour ; 44(4): 849-860, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38974733

RESUMO

The use of natural ingredients in meat processing has recently gained considerable interest, as consumers are increasingly attracted to clean-label meat products. However, limited research has been conducted on the use of natural substitutes for synthetic phosphates in the production of clean-label meat products. Therefore, this study aimed to explore the potential of oyster shell powder as a substitute for synthetic phosphates in pork patties cured with Chinese cabbage or radish powders. Four different groups of patties were prepared using a combination of 0.3% or 0.6% oyster shell powder and 0.4% Chinese cabbage or radish powder, respectively. These were compared with a positive control group that contained added nitrite, phosphate, and ascorbate and a negative control group without these synthetic ingredients. The results showed that patties treated with oyster shell powder had lower (p<0.05) cooking loss, thickness and diameter shrinkage, and lipid oxidation than the negative control but had lower (p<0.05) residual nitrite content and curing efficiency than the positive control. However, the use of 0.6% oyster shell powder adversely affected the curing process, resulting in a decreased curing efficiency. The impact of the vegetable powder types tested in this study on the quality attributes of the cured pork patties was negligible. Consequently, this study suggests that 0.3% oyster shell powder could serve as a suitable replacement for synthetic phosphate in pork patties cured with Chinese cabbage or radish powders. Further research on the microbiological safety and sensory evaluation of clean-label patties during storage is required for practical applications.

2.
Cureus ; 16(5): e60040, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38854283

RESUMO

INTRODUCTION: Dental caries in primary teeth remains a critical public health challenge globally. Although fluoride toothpaste is the standard care for remineralization, its efficacy is limited by the requirement for bioavailable calcium and phosphate ions and its diminished performance on irregular dental surfaces. This study evaluates natural alternatives for dental care, focusing on their mineralizing potential compared to fluoride. AIM: This study aims to assess and compare the efficacy of remineralization by flaxseed paste and chicken eggshell paste to that of standard fluoride toothpaste on artificially demineralized primary teeth. MATERIALS AND METHODS: We utilized an in vitro model, creating standardized white spot lesions on extracted primary teeth to simulate early carious lesions. The teeth were treated with preparations of flaxseed paste, chicken eggshell paste, and fluoride toothpaste. Remineralization was quantitatively analyzed using scanning electron microscopy-energy dispersive x-ray analysis (SEM-EDX) conducted with a high-resolution scanning electron microscope (HRSEM) from Thermoscientific Apreo S at Sir C V Raman Research Park, SRM Institute of Science & Technology, Kattankulathur, Chennai, Tamil Nadu. RESULTS: Quantitative analysis revealed that both flaxseed and chicken eggshell pastes not only met but, in some cases, exceeded the remineralization performance of fluoride toothpaste. Significant differences were observed in the deposition of calcium and phosphate ions on the lesion surfaces. CONCLUSION: The study conducted at the Department of Pediatric and Preventive Dentistry at SRM Dental College, Kattankulathur, confirms the potential of flaxseed and chicken eggshell pastes as viable, cost-effective, and accessible alternatives to fluoride toothpaste for the remineralization of enamel in primary teeth. These findings support the inclusion of these natural agents in oral hygiene regimens and underscore the importance of further research into holistic approaches for the prevention and treatment of dental caries in children.

3.
Heliyon ; 10(8): e29699, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38681621

RESUMO

To investigate the effect of oyster shell powder (OSP) on the static and dynamic properties of expansive soil, the mechanical properties of modified soil were obtained. Taking Ningming expansive soil as the research object, triaxial shear test, dynamic triaxial test and scanning electron microscope test were carried out on plain soil and 9 % expansive soil modified by oyster shell powder (ESMO). The results show that compared with plain soil, the effective cohesion of modified expansive soil with dosp < 1 mm (ESMO (dosp < 1 mm)) and dosp < 0.075 mm (ESMO (dosp < 0.075 mm)) is increased by 15.4 % and 32.8 %, respectively. Under cyclic loading, compared with plain soil, the plastic strain stability value of ESMO (dosp<0.075 mm) is reduced by 40.2 %, the pore water pressure stability value is reduced, and the stiffness is increased. The dynamic mechanical properties of ESMO (dosp<1 mm) showed the opposite trend. Through microscopic experimental analysis, the main reasons for this phenomenon are the particle size distribution, bonding form, and cementation of the two. The results can provide a theoretical basis for the practical application of ESMO and the establishment of constitutive model.

4.
Materials (Basel) ; 17(6)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38541579

RESUMO

A favorable environment for fungi colonization in building materials' surfaces can emerge when certain hygrothermal conditions occur. Thus, reducing fungal growth susceptibility is of major interest. Furthermore, if the integration of bio-wastes is performed in parallel with the development of innovative materials for this purpose, a more sustainable and environmentally friendly material can be obtained. In this study, the fungal susceptibility of lime mortars incorporating almond-shell powder (ASP) microparticles (2 and 4%, wt.-wt. in relation to the binder content) was evaluated. The particle-dispersion technique was employed to prepare the bio-waste introduced in the mixtures. The fungal susceptibility of ASP samples was compared with nanotitania (n-TiO2) with recognized antifungal properties. Mechanical strength, water absorption, and wettability tests were also performed for a better characterization of the composites. Although the addition of 2% ASP led to mechanical properties reduction, an increase in the compressive and flexural strength resulted for 4% of the ASP content. Difficulties in fungal growth were observed for the samples incorporating ASP. No fungal development was detected in the mortar with 2% of ASP, which may be correlated with an increase in the surface hydrophobic behavior. Furthermore, mortars with ASP revealed a reduction in water absorption by capillarity ability, especially with 4% content, suggesting changes in the microstructure and pore characteristics. The results also demonstrated that an improvement in the physical and mechanical properties of the lime mortars can be achieved when ASP microparticles are previously subjected to dispersion techniques.

5.
Foods ; 13(3)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38338505

RESUMO

This study investigated the efficacy of heated scallop shell powder (HSSP) treatment in preserving chicken thigh meat. Chicken thigh meat was treated with HSSP slurry (1% and 5%) for 60 min, and the variation in aerobic bacteria and coliform populations was assessed during refrigerated storage (10 °C). There was a substantial increase in aerobic bacteria, reaching nearly 7 log10 colony forming unit (CFU)/g following 7 days of refrigeration, in the untreated chicken meat. Conversely, the aerobic bacterial population of the HSSP-treated chicken was <5 log10 CFU/g. Coliform growth in the untreated chicken reached over 5 log10 CFU/g following 7 days. In contrast, the coliform population of the HSSP-treated chicken did not reach 5 log10 CFU/g at 1% HSSP concentration; it was suppressed to <4 log10 CFU/g at 5% concentration. Listeria monocytogenes, which can grow at low temperatures, was inoculated into the chicken meat (5 log10 CFU/g) treated with alcohol, which was followed by HSSP. In the untreated chicken, L. monocytogenes increased to 9 log10 CFU/g even when refrigerated for 7 days. However, in the chicken treated with 5% HSSP, L. monocytogenes was suppressed to approximately 3 log10 CFU/g. These findings reveal that HSSP treatment is an effective method for disinfecting meat, inhibiting bacterial growth, and enhancing preservation.

6.
Environ Sci Technol ; 58(5): 2404-2412, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38252973

RESUMO

Carbon capture, utilization, and storage (CCUS) are widely recognized as a promising technology for mitigating climate change. CO2 mineralization using Ca-rich fluids and high-concentration CO2 gas has been studied extensively. However, few studies have reported CO2 mineralization with atmospheric CO2, owing to the difficulty associated with its low concentration. In seawater, the biomineralization process promotes Ca accumulation and CaCO3 precipitation, assisted by specific organic matter. In this study, we examined the conversion of atmospheric CO2 into CaCO3 in seawater using shell powders (Pinctada fucata, Haliotis discus, Crassostrea gigas, Mizuhopecten yessoensis, Turbo sazae, and Saxidomus purpurata). Among the six species, the shell powder of S. purpurata showed the highest rate of CaCO3 formation and recovery of CaCO3. NaClO treatment test revealed that the organic matter in the shells enhanced the CO2 mineralization. All materials used in this study, including atmospheric CO2, seawater, and shells, are economically feasible for large-scale applications. Using shell powder for CO2 mineralization in seawater embodies an innovative technological advancement to address climate change.


Assuntos
Dióxido de Carbono , Gastrópodes , Animais , Pós , Água do Mar , Calcificação Fisiológica
7.
Int J Toxicol ; 43(1_suppl): 82S-95S, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38166445

RESUMO

The Expert Panel for Cosmetic Ingredient Safety (Panel) assessed the safety of 13 Butyrospermum parkii (shea)-derived ingredients, which are most frequently reported to function in cosmetics as skin and hair conditioning agents. The Panel reviewed the available data to determine the safety of these ingredients. Because final product formulations may contain multiple botanicals, each containing similar constituents of concern, formulators are advised to be aware of these constituents and to avoid reaching levels that may be hazardous to consumers. Industry should use good manufacturing practices to limit impurities that could be present in botanical ingredients. The Panel concluded that these ingredients are safe in the present practices of use and concentration when formulated to be non-sensitizing.


Assuntos
Cosméticos , Cosméticos/toxicidade , Qualidade de Produtos para o Consumidor
8.
Nanomaterials (Basel) ; 14(2)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38251114

RESUMO

Our study is focused on optimizing the synthesis conditions for the in situ oxidation of Fe particles to produce Fe@Fe3O4 core-shell powder and preparation via co-precipitation of ZnFe2O4 nanoparticles to produce Fe@Fe3O4/ZnFe2O4 soft magnetic composites (SMC) through a hybrid cold-sintering/spark plasma-sintering technique. XRD and FTIR measurements confirmed the formation of a nanocrystalline oxide layer on the surface of Fe powder and the nanosized nature of ZnFe2O4 nanoparticles. SEM-EDX investigations revealed that the oxidic phase of our composite was distributed on the surface of the Fe particles, forming a quasi-continuous matrix. The DC magnetic characteristics of the composite compact revealed a saturation induction of 0.8 T, coercivity of 590 A/m, and maximum relative permeability of 156. AC magnetic characterization indicated that for frequencies higher than 1 kHz and induction of 0.1 T, interparticle eddy current losses dominated due to ineffective electrical insulation between neighboring particles in the composite compact. Nevertheless, the magnetic characteristics obtained in both DC and AC magnetization regimes were comparable to those reported for cold-sintered Fe-based SMCs.

9.
Chemosphere ; 345: 140505, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37866493

RESUMO

With the rapid development of aquaculture, the production of oyster shells has surged, posing a potential threat to the environment. While oyster shell powder is widely recognized for its inherent alkalinity and rich calcium carbonate content, making it a superior soil conditioner, its role in organic solid waste composting remains underexplored. To investigate the effects of varying concentrations of oyster shell powder on compost maturation and calcium activation, this study employed thermophilic co-composting with acidic sugar residue and bean pulp, incorporating 0% (control), 10% (T1), 20% (T2), 30% (T3), and 40% (T4) oyster shell powder. Findings revealed that appropriate proportions of oyster shell powder significantly enhance temperature stability during composting and elevate maturation levels, notably reducing ammonia emissions between 62.5% and 76.7%. Intriguingly, the calcium in the oyster shell powder was significantly activated during composting, with the 40% addition group achieving the highest calcium activation rate of 48.5%. In summation, the inclusion of oyster shell powder not only optimizes the composting process but also efficiently activates the calcium, resulting in an alkaline organic-inorganic composite soil conditioner with high exchangeable calcium content. This research holds significant implications for promoting the high-value utilization of oyster shells.


Assuntos
Compostagem , Ostreidae , Animais , Resíduos Sólidos , Cálcio , Pós , Solo/química , Carbonato de Cálcio , Cálcio da Dieta
10.
Materials (Basel) ; 16(20)2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37895600

RESUMO

This paper investigated, for the first time, the feasibility of using peanut shell powder, a plant waste residue, as a modifier for asphalt, particularly its self-healing ability. Modified asphalt samples were prepared using varying particle size ranges and concentrations of peanut shell powder. Various tests, including fatigue-healing-fatigue tests, high- and low-temperature rheological property tests, penetration tests for conventional performance, and atomic force microscopy scans, were conducted to investigate the effects of peanut shell powder on the self-healing performance and other properties of asphalt. The results showed that the porous structure of peanut shell powder was able to absorb light components within the asphalt and release them under load, thus improving the self-healing and fatigue resistance properties of the modified asphalt. Experimental conditions such as temperature, healing time, and fatigue damage level also influenced the self-healing performance of asphalt. Additionally, peanut shell powder could increase the dynamic viscosity and high-temperature rheological property of modified asphalt while reducing its temperature susceptibility. However, it had a negative impact on the low-temperature ductility and creep rate, which could potentially lead to premature cracking of asphalt pavement in colder regions. Increasing the content of peanut shell powder and reducing its particle size within a certain range had positive effects. When the content of peanut shell powder was 4% and the particle size range was 80-100 mesh, the overall performance of modified asphalt was satisfactory.

11.
Environ Geochem Health ; 45(12): 9599-9619, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37776470

RESUMO

Groundwater pollution caused by lead ions has become a widespread issue worldwide due to the ever-increasing development of industrial activities. Such pollution poses significant threats to both humans and the environment. Oyster shell powder-peanut shell biochar mixture (OSP-PSB mixture) was used for lead-contaminated groundwater treatment by permeable reactive barrier (PRB) technology. Basic characteristics of materials proved that OSP-PSB mixture has good adsorption properties; OSP with particle sizes ranging from 0.85 to 1.18 mm was used in this research; according to engineering and adsorption characteristics, OSP-PSB mixture (5:1) showed excellent permeability (4.35 × 10-4 cm/s) and lead adsorption capacity(27 mg/g); long-term permeability of the OSP-PSB mixture slightly decreased over time and met the permeability requirements for PRB; the removal mechanisms of lead ions by OSP-PSB mixture include precipitation, surface complexation, ion exchange, and physical adsorption. The experiment results showed that the OSP-PSB mixture fulfills the actual project requirements of PRB.


Assuntos
Água Subterrânea , Ostreidae , Poluentes Químicos da Água , Humanos , Animais , Arachis , Poluentes Químicos da Água/análise , Pós , Adsorção , Íons
12.
Chem Pharm Bull (Tokyo) ; 71(8): 655-660, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37532535

RESUMO

Eutrophication is caused by the inflow of nutrients, such as phosphorus and nitrogen, into closed waterbodies from wastewater. Calcination of oyster shells greatly increases their capacity for phosphate removal; however, information available on this mechanism and the capacity for phosphate removal under different initial pH values and temperatures is less. Herein, we investigated the utilization of oyster shells for phosphate removal under different pH and temperature conditions. Oyster shell powder (OSP) was calcined in a muffle furnace at temperature ranges of 200-1000 °C. Each OSP sample was added to a phosphate solution and the suspension was shaken under different pH and temperature conditions. The main component of OSP changed from CaCO3 to CaO after calcination at approx. 800 °C. The amount of phosphate removal by the calcined OSPs at 800 and 1000 °C was higher than that removal by the other OSPs. Further, the amount of calcium elution from the OSPs calcined at 800 and 1000 °C was higher than that elution from the other OSPs. This was because the solubility of CaO was higher than that of CaCO3. The amount of phosphate removal by the OSP and calcined OSPs at 200-600 °C was the highest at pH 5-7, and increased with increasing reaction temperature. These findings suggested that the mechanism of phosphate removal may involve adsorption in the OSP and OSPs calcined at 200-600 °C, whereas it is associated with coagulation settling and adsorption in the OSPs calcined at 800 and 1000 °C.


Assuntos
Ostreidae , Poluentes Químicos da Água , Animais , Fosfatos , Pós , Água , Adsorção , Concentração de Íons de Hidrogênio
13.
Environ Technol ; : 1-15, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37545344

RESUMO

The current study is to develop surface-modified peanut shell granules by incorporating activated carbon to enhance the removal efficiency of Orange G dye (OGD) through adsorption. Activated carbon was prepared from Arachis hypogaea shell (Peanut shell) using a chemical activation method. Ultrasonic Activated Peanut Shell Powder (UAPSP) was characterised using FT-IR and SEM analysis to identify functional groups and assess surface morphology. To determine the optimal conditions, a batch adsorption study was conducted. The results indicated a maximum removal efficiency of 99.5% and a maximum adsorption capacity of 298.36 mg/g under the following parameters: pH 5, temperature 303 K, interaction period of 60 min, a dosage of 0.5 g/L for an OGD concentration of 10 mg/L. The adsorption mechanism in the current system was evaluated using the Langmuir, Freundlich, Sips, Temkin, and D-R isotherms models. Among these, the Langmuir isotherm exhibited the best fit with an R2 value of 0.997. UAPSP demonstrated a monolayer adsorption capacity of 1.9 mg/g for OGD removal. The pseudo-second-order kinetic model provided the most effective fit with an R2 value of 0.998. Thermodynamic studies revealed that the adsorption process was spontaneous and exothermic, as evidenced by the negative values of ΔG° ( -1.497) and ΔS° (16.4052) at 303 K. Additionally, the mean free energy value (E) in the D-R isotherm increased to 10.58 KJ/mol with a temperature rise from 303 K to 343 K. The characterisation results confirmed that UAPSP is an effective, cost-free, and commercial alternative adsorbent for the removal of hazardous dyes from wastewater.

14.
Environ Sci Pollut Res Int ; 30(41): 93519-93530, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37505384

RESUMO

The application of waste oyster shell in agriculture is of extensive concern due to its benefits on improving yields and inhibiting cadmium (Cd) accumulation in edible parts of crops. However, the underlying mechanisms responsible for oyster shell powder (OSP) that decreases Cd accumulation in crops remain poorly understood. This study explored the effects of OSP on growth and Cd accumulation in rice via pot experiments and hydroponics. Pot experiments showed that the application of 1 g·kg-1 OSP improved rice yields and decreased Cd concentrations in all tissues of rice, especially in grains, which was reduced by 43.5%. The pH was increased and the phytoavailability of Cd in soil was reduced by OSP supplementation. In addition, OSP also exhibited high dissolution of Ca, Fe, Zn, and Se. In hydroponics, OSP supply also suppressed Cd accumulation in rice and increased plant growth. Pretreatment with OSP inhibited the accumulation of Cd in the roots and shoots. Simultaneously, OSP reduced the content of Cd in the root cell sap, cell wall, and xylem sap, and downregulated the expression of OsNramp5, OsNramp1, OsIRT1, and OsHMA2. These findings suggested that the application of OSP could reduce Cd accumulation by inhibiting the expression of genes responsible for Cd absorption and xylem loading in rice.


Assuntos
Oryza , Ostreidae , Poluentes do Solo , Animais , Cádmio/análise , Pós , Transporte Biológico , Poluentes do Solo/análise , Raízes de Plantas/metabolismo
15.
Bioresour Technol ; 386: 129576, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37506928

RESUMO

Regulating heavy metal resistance genes (HMRGs) was an effective method for heavy metal resistant bacteria (HMRB) to cope with heavy metal stress during dairy manure composting. This research aimed to investigate heavy metal detoxification mediated by shell powder (SP) in composting and the response of HMRB and HMRGs to changes in heavy metal bioavailability during composting. Research showed that SP additive reduced the bioavailability of Zu, Cu, and Mn by 10.64%, 13.90% and 14.14%, respectively. SP increased the composition percentage of humic acid (HA) in humus (HS) by 8%. SP enhanced the resistance of Actinobacteria to heavy metals and improved the regulation of HMRGs. Correlation analysis demonstrated that the bioavailability of heavy metals was positively correlated with most HMRGs. HA was significantly negatively correlated with the bioavailability of Zn, Cu and Mn. Therefore, SP additive could be a novel strategy for heavy metals detoxification during composting.


Assuntos
Compostagem , Metais Pesados , Pós , Metais Pesados/análise , Solo , Substâncias Húmicas , Bactérias , Esterco
16.
Materials (Basel) ; 16(7)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37049096

RESUMO

Pyrethroids are common contaminants in water bodies. In this study, an efficient mussel shell-based adsorbent was prepared, the effects of factors (calcination temperature, calcination time, and sieved particle size) on the pyrethroid adsorption capacity from calcined shell powder were investigated via Box-Behnken design, and the prediction results of the model were verified. By characterizing (scanning electron microscopy, X-ray diffraction, Fourier infrared spectroscopy, and Brunauer-Emmett-Teller measurements) the adsorbent before and after the optimized preparation process, the results showed that calcined shell powder had a loose and porous structure, and the main component of the shell powder under optimized condition was calcium oxide. The adsorption mechanism was also investigated, and the analysis of adsorption data showed that the Langmuir, pseudo second-order, and intra-particle diffusion models were more suitable for describing the adsorption process. The adsorbent had good adsorption potential for pyrethroids, the adsorption capacity of the two pesticides was 1.05 and 1.79 mg/g, and the removal efficiency was over 40 and 70% at the maximum initial concentration, respectively.

17.
Artigo em Inglês | MEDLINE | ID: mdl-36900930

RESUMO

Excessive N fertilizer application has aggravated soil acidification and loss of N. Although oyster shell powder (OSP) can improve acidic soil, few studies have investigated its ability to retain soil N. Here, the physicochemical properties of latosol after adding OSP and calcined OSP (COSP) and the dynamic leaching patterns of ammonium N (NH4+-N), nitrate N (NO3--N), and Ca in seepage, were examined through indoor culture and intermittent soil column simulation experiments. Various types of N fertilizer were optimized through the application of 200 mg/kg of N, urea (N 200 mg/kg) was the control treatment (CK), and OSP and COSPs prepared at four calcination temperatures-500, 600, 700, and 800 °C-were added to the latosol for cultivation and leaching experiments. Under various N application conditions, the total leached N from the soil followed ammonium nitrate > ammonium chloride > urea. The OSP and COSPs had a urea adsorption rate of 81.09-91.29%, and the maximum reduction in cumulative soil inorganic N leached was 18.17%. The ability of COSPs to inhibit and control N leaching improved with increasing calcination temperature. Applying OSP and COSPs increased soil pH, soil organic matter, total N, NO3--N, exchangeable Ca content, and cation exchange capacity. Although all soil enzyme activities related to N transformation decreased, the soil NH4+-N content remained unchanged. The strong adsorption capacities for NH4+-N by OSP and COSPs reduced the inorganic N leaching, mitigating the risk of groundwater contamination.


Assuntos
Nitrogênio , Ostreidae , Animais , Pós , Nitrogênio/análise , Fertilizantes , Solo/química , Carbonato de Cálcio , Nitratos/análise , Ureia
18.
Materials (Basel) ; 16(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36676539

RESUMO

Mussel shell waste, which is regularly disposed by households, restaurants, markets, or farms, causes environmental problems worldwide, including in Thailand, because of its long decomposing time. Owing to a large amount of calcium (Ca) content from calcium carbonate (CaCO3) in mussel shell waste, many Thai local businesses grind the shell waste into powder and sell it as a source of Ca. Generally, these powdered waste shells are a mixture of various types of mussel shell waste. In this study, we investigated and characterized powdered mixed waste shells sold in a local Thai market (called mixed shell powder) and ground shells from waste green mussel shells (called green mussel shells) prepared in the laboratory after calcination at different temperatures (800 °C, 900 °C, and 1000 °C). Mixed shell powder containing five different types of mussel shells and green mussel shells were calcined for 2 h and 3 h, respectively. The time used for calcination of mixed shell powder and green mussel shells was different due to the different particle sizes of both shell wastes. We found that an optimal temperature of 1000 °C completely converted CaCO3 to CaO in both samples. The nanoscale size of CaO was detected at the surface of calcined shells. These shell wastes can be used as a bioresource of CaO.

19.
J Biomater Sci Polym Ed ; 34(10): 1360-1381, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36644798

RESUMO

The regeneration of bone defects is a major challenge for clinical orthopaedics. Herein, we designed and prepared a new type of bioactive material, using stingray skin collagen and oyster shell powder (OSP) as raw materials. A stingray skin collagen/oyster osteoinductive composite scaffold (Col-OSP) was prepared for the first time by genipin cross-linking, pore-forming and freeze-drying methods. These scaffolds were characterized by ATR-FTIR, SEM, compression, swelling, cell proliferation, cell adhesion, alkaline phosphatase activity, alizarin red staining and RT-PCR etc. The Col-OSP scaffold had an interconnected three-dimensional porous structure, and the mechanical properties of the Col-OSP composite scaffold were enhanced compared with Col, combining with the appropriate swelling rate and degradation rate, the scaffold was more in line with the requirements of bone tissue engineering scaffolds. The Col-OSP scaffold was non-toxic, promoted the proliferation, adhesion, and differentiation of MC3T3-E1 cells, and stimulated the osteogenesis-related genes expressions of osteocalcin (OCN), collagen type I (COL-I) and RUNX2 of MC3T3-E1 cells.


Assuntos
Ostreidae , Rajidae , Animais , Alicerces Teciduais/química , Colágeno/química , Engenharia Tecidual/métodos , Osteogênese
20.
Foods ; 12(2)2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36673504

RESUMO

In this study, the extraction of cocoa shell powder (CSP) was optimized, and the optimized extracts were spray-dried for encapsulation purposes. Temperature (45−65 °C), extraction time (30−60 min), and ethanol concentration (60−100%) were the extraction parameters. The response surface methodology analysis revealed that the model was significant (p ≤ 0.05) in interactions between all variables (total phenolic compound, total flavonoid content, and antioxidant activity as measured by 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP assays), with a lack of fit test for the model being insignificant (p > 0.05). Temperature (55 °C), time (45 min), and ethanol concentration (60%) were found to be the optimal extraction conditions. For spray-drying encapsulation, some quality metrics (e.g., water solubility, water activity) were insignificant (p > 0.05). The microcapsules were found to be spherical in shape using a scanning electron microscope. Thermogravimetric and differential thermogravimetric measurements of the microcapsules revealed nearly identical results. The gum arabic + maltodextrin microcapsule (GMM) showed potential antibacterial (zone of inhibition: 11.50 mm; lower minimum inhibitory concentration: 1.50 mg/mL) and antioxidant (DPPH: 1063 mM trolox/100g dry wt.) activities (p ≤ 0.05). In conclusion, the microcapsules in this study, particularly GMM, are promising antioxidant and antibacterial agents to be fortified as functional food ingredients for the production of nutraceutical foods with health-promoting properties.

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