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1.
Polymers (Basel) ; 16(6)2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38543386

ABSTRACT

Developing a powder-form natural antioxidant additive involves utilizing polyphenols extracted from agro-industrial wastes (walnut green husk). This research explores chickpea proteins (CPP) as an emergent encapsulating agent to enhance the stability and shelf life of the antioxidant additive. This study aims to develop a natural antioxidant powder additive based on polyphenols obtained from walnut green husks encapsulated by chickpea protein (5%, 7.5%, and 10% w/v) to evaluate their effect under storage at relative humidities (33 and 75% RH). The physicochemical and structural properties analysis indicated that better results were obtained by increasing the protein concentration. This demonstrates the protective effect of CPP on the phenolic compounds and that it is potentially non-toxic. The results suggest that the optimal conditions for storing the antioxidant powder, focusing on antioxidant activity and powder color, involve low relative humidities (33%) and high protein concentration (10%). This research will contribute to demonstrating chickpea protein as an emerging encapsulating agent and the importance of the cytotoxic analysis of extracts obtained from agroindustrial wastes.

2.
Arch Microbiol ; 206(1): 23, 2023 Dec 16.
Article in English | MEDLINE | ID: mdl-38103058

ABSTRACT

In this study, IBCB 66, IBCB 868, and CBMAI 1306 isolates of Beauveria bassiana were grown in liquid culture for 4 days, leading to elevated submerged spores (SS) levels. The influence of the addition of different glycerol concentrations (0, 3, and 6%) (v/v) in the liquid culture was investigated regarding the stability (at 4 and 27 °C) of dried formulations. The virulence of SS was compared with aerial spores (AS) against Tetranychus urticae (Koch) (Acari: Tetranychidae). The results demonstrate the potential of using SS to control T. urticae. CBMAI 1306 and IBCB 868 isolates caused T. urticae mortality rates of 91.11% and 88.89% 5 days after treatment, respectively, when applied at concentrations of 1 × 108 SS mL-1. The median Lethal Time (LT50) values for these strains were 2.64 and 2.61 days, respectively. The dried formulations showed potential acaricidal activity. Higher glycerol concentrations in the liquid culture medium reduced formulation stability at 27 °C.


Subject(s)
Beauveria , Tetranychidae , Animals , Spores, Fungal , Virulence , Glycerol/pharmacology , Pest Control, Biological/methods
3.
Int J Biol Macromol ; 253(Pt 1): 126610, 2023 Dec 31.
Article in English | MEDLINE | ID: mdl-37652330

ABSTRACT

This study aimed to produce oleogels based on non-germinated and germinated wheat starches with orange essential oil, apply them to replace hydrogenated vegetable fat in bread, and assess the antifungal action. The oleogels were prepared using sunflower oil, wheat starches, beeswax, water, and orange essential oil (OEO). They were evaluated to determine the volatile compounds, oil binding capacity, texture profile, storage stability for 20 days, thermogravimetric analysis, and functional groups. The breads were evaluated by their moisture content, specific volume, texture profile, volatile compounds, and microbiological contamination during 15 days of storage. The oleogels showed high storage stability, were fully intact after 20 days of storage, and had a high oil binding capacity (∼100 %). The oleogels with OEO presented increased adhesiveness and reduced hardness compared to the ones without essential oil. The oleogels with OEO based on germinated wheat starch released a high amount of volatile compounds. Substituting saturated vegetable fat with oleogels in bread formulation resulted in decreased hardness and maintained specific volume. Furthermore, incorporating OEO oleogels in the bread led to reduced growth of total mesophiles and fungi.


Subject(s)
Bread , Oils, Volatile , Bread/analysis , Triticum , Vegetables , Oils, Volatile/pharmacology , Starch , Fatty Acids/analysis
4.
Appl Microbiol Biotechnol ; 107(21): 6671-6682, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37606788

ABSTRACT

Several plant growth-promoting bacteria (PGPB) are gram-negative, and their cell viability is affected during the bio-inoculant production. Hence, formulation-drying processes provide challenges that limit the adoption of these beneficial microorganisms in sustainable agricultural production. Among delivery system strategies for gram-negative PGPB, the encapsulating cells in biopolymeric materials are emerging as a promising alternative. This research aims to evaluate the effect of additives and crosslinking agents on the survival of the consortium of Herbaspirillum frisingense AP21, Azospirillum brasilense D7, and Rhizobium leguminosarum T88 in hydrogel capsules. Three crosslinkers and diverse potential drying protectors were tested. Calcium gluconate provides notable consortium survival advantages regarding colony-forming units (CFUs) (losses of up to 4 log CFU) compared to calcium lactate and calcium chloride (up to 6 log CFU). Additives such as skimmed milk, whey protein, and Gelita® EC improve the recovery of viable cells after the drying process, demonstrating an increase in cell survival of the three bacteria by up to 4 log CFU. The combination of these substances into a capsule prototype extends the storage stability of bacterial consortium up to 3 months at 18 ± 2 °C. This study expands the knowledge for formulating gram-negative PGPB consortium, regarding the crosslinker and drying protector relationship on encapsulation processes with drying survival and further storage stability performance. KEY POINTS: • Hydrogel immobilization formulation approach for PGPB consortium • Enhancing drying survival of gram-negative PGPB consortium • Increasing storage stability of PGPB consortium at 18 °C.

5.
Foods ; 12(2)2023 Jan 05.
Article in English | MEDLINE | ID: mdl-36673344

ABSTRACT

Probiotics are associated with health benefits to the host. However, their application can be limited due to a decrease in cell viability during processing, storage, and passage through the gastrointestinal tract. Microencapsulation is a simple and efficient alternative to improve the physical protection and stability of probiotics. The present study aimed to produce and characterize alginate or gelatin-based microparticles containing Lactobacillus acidophilus NRRL B-4495 or Lactiplantibacillus plantarum NRRL B-4496 by oil-in-water (O/W) emulsification and to evaluate the stability under storage conditions. The results showed that L. acidophilus and L. plantarum encapsulated in gelatin (LAEG and LPEG) presented diameters of 26.08 ± 1.74 µm and 21.56 ± 4.17 µm and encapsulation efficiencies of 89.6 ± 4.2% and 81.1 ± 9.7%, respectively. However, those encapsulated in alginate (LAEA and LPEA) showed an encapsulation efficiency of <1.0%. Furthermore, LAEG was stable for 120 days of storage at 5 °C and 25 °C. Therefore, encapsulation in gelatin by O/W emulsification is a promising strategy for protecting and stabilizing probiotic bacteria, enabling future application in foods.

6.
F1000Res ; 12: 1174, 2023.
Article in English | MEDLINE | ID: mdl-38933490

ABSTRACT

Background: Strawberry is a fruit with a high antioxidant capacity due to its richness in phenolic compounds that suffer a rapid post-harvest deterioration. Spray drying is an alternative to reduce losses; however, these powders present problems of instantanisation, making it necessary to implement agglomeration processes. During storage, powdered food products can undergo a series of changes in their amorphous state from a product initially in a vitreous state to a gummy state, where all properties are substantially modified due to the increased mobility of water in the matrix. Methods: The research objective was to evaluate the storage stability (6 months) of a fluidized bed agglomerated strawberry powder mixture at three temperatures (15, 25 and 25°C), a controlled environment at 65% relative moisture, and PET foil laminated film bags as packaging. Moisture, water activity, bulk and compacted density, Carr and Hausner indices, solubility, hygroscopicity, wettability, angle of repose, antioxidant capacities, total phenols, anthocyanins, vitamin C, color (CIE-Lab) and particle size were monitored. Results: ANOVA showed statistically significant differences (p<0.05) for all dependent variables concerning storage time; storage temperature had no significant effect on S, ABTS, DPPH and Hu. The time-temperature interaction during storage had no significant effect (p>0.05) on S, ABTS, DPPH, Hu and L. The agglomerate showed moisture and aw values that confer excellent stability against deterioration reactions; it retained good fluidity, low cohesiveness, and retentions above 50% for antioxidant capacity, 76% for total phenols, 39% for anthocyanins, and 40% for vitamin C; particle size was retained during the evaluation. The color was only affected in the 35°C treatment from the fifth month onwards. Conclusions: The study will serve as a tool for the determination of the shelf life of the chipboard once the critical values of the attributes selected as predictors of shelf life are defined.


Subject(s)
Antioxidants , Fragaria , Powders , Fragaria/chemistry , Antioxidants/chemistry , Food Storage/methods , Phenols/analysis , Phenols/chemistry , Temperature , Spray Drying , Particle Size , Anthocyanins/chemistry , Anthocyanins/analysis , Ascorbic Acid/chemistry , Ascorbic Acid/analysis
7.
Foods ; 11(17)2022 Aug 24.
Article in English | MEDLINE | ID: mdl-36076743

ABSTRACT

Guaraná byproducts are rich in carotenoids, featuring strong antioxidant capacity and health-promoting benefits. However, these compounds are highly susceptible to oxidation and isomerization, which limits their applications in foods. This research aimed to encapsulate the carotenoid-rich extract from reddish guaraná peels by spray drying (SD), chilling (SC), and their combination (SDC) using gum arabic and vegetable fat as carriers. The carotenoid-rich extract was analyzed as a control, and the formulations were prepared with the following core-carrier ratios: SD20 (20:80), SD25 (25:75), SD33 (33:67), SC20 (20:80), SC30 (30:70), SC40 (40:60), SDC10 (10:90), and SDC20 (20:80). The physicochemical properties of the formed microparticles were characterized, and their storage stability was evaluated over 90 days. Water activity of microparticles formed during the SD process increased during storage, whereas those formed by SC and SDC processes showed no changes in water activity. The formed microparticles exhibited color variation and size increase over time. Carotenoid degradation of the microparticles was described by zero-order kinetics for most treatments. Considering the higher carotenoid content and its stability, the optimum formulation for each process was selected to further analysis. Scanning electron micrographs revealed the spherical shape and absence of cracks on the microparticle surface, as well as size heterogeneity. SD increased the stability to oxidation of the carotenoid-rich extract by at least 52-fold, SC by threefold, and SDC by 545-fold. Analysis of the thermophysical properties suggested that the carrier and the process of encapsulation influence the powder's thermal resistance. Water sorption data of the SDC microparticles depended on the blend of the carrier agents used in the process. Carotenoid encapsulation via an innovative combination of spray drying and spray chilling processes offers technological benefits, which could be applied as a promising alternative to protect valuable bioactive compounds.

8.
Food Res Int ; 159: 111620, 2022 09.
Article in English | MEDLINE | ID: mdl-35940811

ABSTRACT

This study aimed to assess Spirulina platensis, Chlorella vulgaris, Scenedesmus quadricauda, and Lagerheimia longiseta microalgae potential as protective agents for probiotic cultures [(Lactobacillus acidophilus (La-05) and Lacticaseibacillus casei (Lc-01)] during freeze-drying, refrigeration storage (4 °C, 120 days), and in vitro simulated gastrointestinal conditions (SGIC). The occurrence of membrane damage and ultrastructural aspects of the cells were also verified. Fructooligosaccharides (FOS) were used as a positive control and saline solution as a negative control. The effects of the cryoprotectants on probiotic survival depended on the tested probiotic culture and microalgae biomass. For La-05, all tested cryoprotectants caused a lower reduction in probiotic counts during the freeze-drying and up to 90 days of storage. S. platensis kept higher probiotic counts during storage, while C. vulgaris protected the probiotic against the SGIC. L. longiseta decreased the probiotic membrane damage, mainly due to the production of exopolysaccharides, which was observed in the scanning electron microscopy (SEM). For Lc-01, all tested cryoprotectants promoted a lower reduction in probiotic counts up to 120 days of storage. FOS and S. quadricauda protected the probiotics during freeze-drying and refrigeration storage, while C. vulgaris protected the probiotic against the SGIC and caused lower membrane damage, mainly due to physical protection observed in SEM. In conclusion, microalgae biomasses exerted similar or better cryoprotectant effects on probiotics than FOS, a recognized cryoprotective agent.


Subject(s)
Chlorella vulgaris , Lacticaseibacillus casei , Microalgae , Probiotics , Biomass , Cryoprotective Agents/pharmacology , Fresh Water , Lactobacillus acidophilus , Probiotics/chemistry
9.
Braz. J. Pharm. Sci. (Online) ; 58: e18665, 2022. tab, graf
Article in English | LILACS | ID: biblio-1374559

ABSTRACT

Abstract Suitability of developing Spirulina incorporated cereal based low cost nutritious extrudates was analysed against extrusion processing parameters. Most significant extrusion processing parameters considered for present study were feed moisture (20-25%), die temperature (100-120 °C) and screw speed (50-100 rpm). Different extrusion conditions were used to obtain most acceptable rice: Spirulina blend extrudates. In present study before extrusion processing different additives (citric acid and sodium bicarbonate) were added in rice: Spirulina blend and checked its effect on colour degradation kinetics at varied packaging and storage conditions. Higher screw speed (100 rpm) indicating less residence time of feed material inside the barrel resulted in higher colour retention of rice: Spirulina (97:03) blend extrudates. Kinetics for rice: Spirulina (97:03) blend extrudates indicates faster rate of colour degradation in terms of lightness (half-life of 4 days) when packed in metalized polyethylene at 50°C with 65% relative humidity. Increased concentration of Spirulina (1-3%) in raw formulations resulted in increase in concentration of all amino acids. Impact of extrusion processing has shown non-significant (p ≤ 0.05) effect on amino acid concentrations of rice: Spirulina blend extrudates. Also, all the spirulina added samples showed good consumer acceptability with the score of 6.7


Subject(s)
Edible Grain/classification , Biomass , Microalgae/classification , Amino Acids/adverse effects , Oryza/classification , Low Cost Technology , Product Packaging/instrumentation , Residence Time , Spirulina/metabolism , Half-Life , Humidity/adverse effects
10.
Foods ; 9(5)2020 May 19.
Article in English | MEDLINE | ID: mdl-32438746

ABSTRACT

Black bean is a source of anthocyanins and other phenolic compounds that are associated with health benefits. This work aimed to optimize the extraction and determine the stability and biological potential of black bean anthocyanin-rich extracts recovered by supercritical fluid extraction (SFE) and pressurized liquid extraction (PLE). The highest concentration of anthocyanins and total phenolic compounds were recovered with SFE using 300 bar, 60 °C and co-solvent ethanol/distilled water (50/50, v/v). Eleven non-colored phenolic compounds were identified in SFE extract using Ultra performance liquid chromatography - Electrospray ionization-Quadrupole -Time of flight - Mass spectrometry (UPLC-ESI-QToF-MS/MS). Myricetin, syringic acid, rutin hydrate and chlorogenic acid presented the highest relative area among identified compounds. Compared to leaching extraction, SFE extracts showed a similar storage stability at 4, 25 and 32 °C (p < 0.05), but with a higher antioxidant potential (2,2-diphenyl-1-picryl-hydrazil (DPPH) IC50: 0.078 ± 0.01; 2,2'-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) IC50: 0.161 ± 0.03) and antidiabetic potential (α-amylase IC50: 124.76 ± 12.97; α-glucosidase IC50: 31.30 ± 0.84; dipeptidyl peptidase-IV IC50: 0.195 ± 0.01). SFE extraction is an efficient method to obtain anthocyanins and other phenolic compounds with exceptional biological potential.

11.
Anal Bioanal Chem ; 411(11): 2301-2315, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30798340

ABSTRACT

Adulteration is a recurrent issue found in fuel screening. Commercial diesel contamination by kerosene is highly difficult to be detected via physicochemical methods applied in market. Although the contamination may affect diesel quality and storage stability, there is a lack of efficient methodologies for this evaluation. This paper assessed the use of IR spectroscopies (MIR and NIR) coupled with partial least squares (PLS) regression, support vector machine regression (SVR), and multivariate curve resolution with alternating least squares (MCR-ALS) calibration models for quantifying and identifying the presence of kerosene adulterant in commercial diesel. Moreover, principal component analysis (PCA), successive projections algorithm (SPA), and genetic algorithm (GA) tools coupled to linear discriminant analysis were used to observe the degradation behavior of 60 samples of pure and kerosene-added diesel fuel in different concentrations over 60 days of storage. Physicochemical properties of commercial diesel with 15% kerosene remained within conformity with Brazilian screening specifications; in addition, specified tests were not able to identify changes in the blends' performance over time. By using multivariate classification, the samples of pure and contaminated fuel were accurately classified by aging level into two well-defined groups, and some spectral features related to fuel degradation products were detected. PLS and SVR were accurate to quantify kerosene in the 2.5-40% (v/v) range, reaching RMSEC < 2.59% and RMSEP < 5.56%, with high correlation between real and predicted concentrations. MCR-ALS with correlation constraint was able to identify and recover the spectral profile of commercial diesel and kerosene adulterant from the IR spectra of contaminated blends.

12.
J Appl Microbiol ; 124(3): 810-820, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29327477

ABSTRACT

AIMS: Nitrogen is a critical element in industrial fermentation media. This study investigated the influence of various nitrogen sources on blastospore production, desiccation tolerance and storage stability using two strains of the cosmopolitan insect-pathogenic fungus Beauveria bassiana. METHODS AND RESULTS: Complex organic sources of nitrogen such as soy flour, autolysed yeast and cottonseed flour induced great numbers of blastospores after 2-3 days of fermentation, which also survived drying and remained viable (32-56% survival) after 9 months storage at 4°C, although variations were found between strains. Nitrogen availability in the form of free amino acids directly influenced blastospore production and resistance to desiccation. Increasing glucose and nitrogen concentrations up to 120 and 30 g l-1 , respectively, did not improve blastospore production but enhanced desiccation tolerance. Cell viability after drying and upon fast-rehydration was increased when ≥25 g acid-hydrolysed casein per litre was supplemented in the liquid culture medium. CONCLUSIONS: These findings indicate that low-cost complex nitrogen compounds are suitable to enhance yeast-like growth by B. bassiana with good desiccation tolerance and therefore support its further scale-up production as a mycoinsecticide. SIGNIFICANCE AND IMPACT OF THE STUDY: Nitrogen is the most expensive nutrient in liquid media composition, but this study underscores the feasibility of using low-cost nitrogen compounds composed mainly of agro-industrial by-products for rapid production of desiccation-tolerant B. bassiana blastospores by liquid culture fermentation.


Subject(s)
Beauveria/metabolism , Nitrogen/metabolism , Spores, Fungal/growth & development , Beauveria/chemistry , Beauveria/growth & development , Culture Media/chemistry , Culture Media/metabolism , Desiccation , Fermentation , Glucose/metabolism , Preservation, Biological , Spores, Fungal/chemistry , Spores, Fungal/metabolism , Water/analysis , Water/metabolism
13.
Appl Microbiol Biotechnol ; 100(19): 8359-70, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27198727

ABSTRACT

The yeast form (blastospore) of the dimorphic insect-pathogenic fungus Beauveria bassiana can be rapidly produced using liquid fermentation methods but is generally unable to survive rapid dehydration processes or storage under non-refrigerated conditions. In this study, we evaluated the influence of two convective drying methods, various modified atmosphere packaging systems, and storage temperatures on the desiccation tolerance, storage stability, and virulence of blastospores of B. bassiana ESALQ 1432. All blastospore formulations were dried to <5 % water content equivalent to aw < 0.3. The viability of B. bassiana blastospores after air drying and spray drying was greater than 80 %. Vacuum-packaged blastospores remained viable longer when stored at 4 °C compared with 28 °C with virtually no loss in viability over 9 months regardless the drying method. When both oxygen and moisture scavengers were added to sealed packages of dried blastospore formulations stored at 28 °C, viability was significantly prolonged for both air- and spray-dried blastospores. The addition of ascorbic acid during spray drying did not improve desiccation tolerance but enhanced cell stability (∼twofold higher half-life) when stored at 28 °C. After storage for 4 months at 28 °C, air-dried blastospores produced a lower LC80 and resulted in higher mortality to whitefly nymphs (Bemisia tabaci) when compared with spray-dried blastospores. These studies identified key storage conditions (low aw and oxygen availability) that improved blastospore storage stability at 28 °C and will facilitate the commercial development of blastospores-based bioinsecticides.


Subject(s)
Beauveria/physiology , Dehydration , Insecticides , Microbial Viability , Product Packaging , Spores, Fungal/physiology , Drug Stability , Drug Storage , Temperature
14.
Braz. arch. biol. technol ; Braz. arch. biol. technol;58(2): 147-153, Mar-Apr/2015. tab, graf
Article in English | LILACS | ID: lil-744309

ABSTRACT

This study evaluated the biological importance of immobilized urease enzyme over the free urease. The support material used for urease immobilization was alginate. Generally, the immobilization of urease in alginate gel showed a marked increase in Km and Vmax. However, the immobilized urease showed higher thermal stability than that of free enzyme. The rate of thermal inactivation of the immobilized enzyme decreased due to entrapment in gel matrix. Also, the activity of the immobilized urease was more stable in retention than that of the free enzyme during the storage in solution, although the activity of the immobilized enzyme was lower in comparison with the free enzyme. A stable immobilized system and long storage life are convenient for applications that would not be feasible with a soluble enzyme system. These results highlighted the technical and biochemical benefits of immobilized urease over the free enzyme.

15.
Food Chem ; 175: 267-72, 2015 May 15.
Article in English | MEDLINE | ID: mdl-25577079

ABSTRACT

Anthocyanins (ANC) are common polyphenolics in plants, but are poorly absorbed into the bloodstream upon consumption. Phospholipids (PL) and terpenes (TP) may serve as enhancing agents in absorption. This study evaluated their role in transepithelial transport within a Caco-2 cell monolayer-model system and impact on ANC stability. Açaí fruit ANC were isolated and found to transport, at a low rate (1.22%), in the absence of soy lecithin phospholipids and Valencia orange terpenes, yet their addition significantly increased the transport of both cyanidin-3-glucoside and cyanidin-3-rutinoside. The best transport results (5.21%) were observed when combinations of PL (5000 mg/l) and TP (50mg/l) were used. The presence of PL and TP had no influence on ANC degradation over a 40 day storage period. Results demonstrated the potential of PL and TP to increase intestinal transport of ANC, and present advancement towards the formulation of functional foods that support improved ANC absorption.


Subject(s)
Anthocyanins/chemistry , Euterpe/chemistry , Fruit/chemistry , Phospholipids/chemistry , Terpenes/chemistry , Anthocyanins/pharmacokinetics , Biological Transport , Caco-2 Cells , Humans , Intestinal Mucosa/metabolism , Phospholipids/pharmacokinetics , Plant Extracts/chemistry , Plant Extracts/pharmacokinetics , Terpenes/pharmacokinetics
16.
J Invertebr Pathol ; 127: 11-20, 2015 May.
Article in English | MEDLINE | ID: mdl-25497914

ABSTRACT

A major constraint to the commercial use of fungal biocontrol agents is the availability of low-cost production media and processes. Previous attempts in producing Beauveria blastospores using liquid culture fermentation processes required long fermentation times (6-8days) and produced cells that had poor survival after desiccation and storage. In this study, isolates of Beauveria bassiana and Isaria fumosorosea were evaluated for blastospore yield, desiccation tolerance, storage stability, and biocontrol efficacy using fermentation media containing acid hydrolyzed casein or cottonseed flour as the nitrogen source. Cultures of B. bassiana and I. fumosorosea grown in media containing cottonseed flour produced high blastospore concentrations (>1×10(9)mL(-1)) after 3days which is comparatively less expensive nitrogen source than acid hydrolyzed casein. The resultant air-dried blastospores (<3% moisture) of all fungal isolates survived drying (61-86% viability), irrespective of the nitrogen source tested. Storage stability at 4°C varied with nitrogen source and fungal strain. Air-dried blastospores of B. bassiana strains showed half-lives >14months in contrast to 9.2-13.1months for I. fumosorosea. Blastospores of B. bassiana and I. fumosorosea killed Bemisia tabaci whitefly nymphs faster and required lower concentrations compared with aerial conidia. Our findings support the use of liquid culture fermentation as a cost-effective process to rapidly produce high yields of stable and infective blastospores of either B. bassiana or I. fumosorosea. These results support further evaluation of blastospore sprayable formulations for the control of soft-bodied insects.


Subject(s)
Cell Culture Techniques/methods , Mycology/methods , Pest Control, Biological/methods , Animals , Beauveria , Culture Media , Desiccation/methods , Fermentation , Hemiptera/parasitology
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