Incorporation Of Ascorbic Acid Research Articles

Evaluating osteogenic effects associated with the incorporation of ascorbic acid in mineralized collagen scaffolds.

Current treatments for craniomaxillofacial (CMF) defects motivate the design of instructive biomaterials that can promote osteogenic healing of complex bone defects. We report methods to promote in vitro osteogenesis of human mesenchymal stem cells (hMSCs) within a model mineralized collagen scaffold via the incorporation of ascorbic acid (vitamin C), a key factor in collagen biosynthesis and bone mineralization. An addition of 5 w/v% ascorbic acid into the base mineralized collagen scaffold significantly changes key morphology characteristics including porosity, macrostructure, and microstructure. This modification promotes hMSC metabolic activity, ALP activity, and hMSC-mediated deposition of calcium and phosphorous. Additionally, the incorporation of ascorbic acid influences osteogenic gene expression (BMP-2, RUNX2, COL1A2) and delays the expression of genes associated with osteoclast activity and bone resorption (OPN, CTSK), though it reduces the secretion of OPG. Together, these findings highlight ascorbic acid as a relevant component for mineralized collagen scaffold design to promote osteogenic differentiation and new bone formation for improved CMF outcomes.

Characteristics of a Lipid Hydrogel and Bigel as Matrices for Ascorbic Acid Stabilization.

Ascorbic acid (AA) has many health benefits, including immune and cardiovascular deficiency protection, prenatal problems, and skin diseases. Unfortunately, AA is easily oxidized and has limited bioavailability. Thus, the development of formulations that stabilize and enhance the efficacy of AA is a challenge. In this study, 4% AA was encapsulated in two recently developed gels, a hydrogel and a bigel. The hydrogel was formed exclusively with lipids and water, and the bigel was a combination of the hydrogel with an oleogel formed with olive oil and beeswax. The effect of AA in gel microstructures was determined using X-ray scattering, rheology, and texture analysis. Additionally, the capacity of these materials to protect AA from degradation upon temperature and sunlight was studied. Results showed that the incorporation of AA into both materials did not affect their microstructure. Moreover, hydrogel-protected AA showed only 2% degradation after three months at 8 °C, while in aqueous solution, it degraded by 12%. Regarding sunlight, bigel showed a good shielding effect, exhibiting only 2% AA degradation after 22 h of exposure, whereas in aqueous solution, AA degraded by 10%. These results suggest that both proposed gels could be used in biomedical applications and the field of food.

Evaluation of Effect of Vitamin C on Streptococcus Mutans Induced Secondary Caries: An In vitro Study

This study aimed to assess and understand the protective effect of vitamin C against secondary caries formation around the margins of class V restorations with the help ofan in-vitro bacterial caries model. In this study, a total of 30 mandibular premolars were chosen and assigned to three groups (n=10). In this study, Class V composite restorations were prepared and along with pretreatment of the cavity walls with various solutions like Vitamin C (ascorbic acid solution), HEPES buffer solution and chlorhexidinedigluconate. After incubating specimens with Streptococcus mutans, dentin and enamel were assessed using Fluorescence Microscopy.The study showed Vitamin C (Ascorbic acid) inhibited the formation of secondary caries near the dentin resin interface. No inhibitory effects were observed in enamel margins. From the study, it could be concluded that the incorporation of ascorbic acid in the restorative procedure of resin composite may inhibit secondary caries formation. Neither the application of chlorhexidine nor HEPES buffer had much effect on the inhibitory effect on secondary caries.

Incorporation of ascorbic acid and L-cysteine in sodium carboxymethyl cellulose coating delays color deterioration and extends the shelf-life of fresh-cut asparagus lettuce (Lactuca sativa var. angustata)

In this study, a series of analyses were performed in an attempt to understand more fully the effects and related mechanisms of chemical additives, edible coatings, and their combination on postponing the color deterioration of fresh-cut asparagus lettuce. Fresh-cut asparagus lettuce was dipped into solutions of 0.67% sodium carboxymethyl cellulose (CMC-Na), 0.38% ascorbic acid (AsA) + 0.85% L-cysteine (L-cys), and their combination for 10 min, respectively. CMC-Na, AsA + L-cys, and their combination repressed discoloration and browning, allowing fresh-cut asparagus lettuce to retain its appearance of freshness during storage; however, the combination solution had a more pronounced and synergistic effect. The repression of discoloration/browning of fresh-cut asparagus lettuce was associated with a reduction in the activity and transcription of browning enzymes (polyphenol oxidase and peroxidase) and the phenol content. The solution treatments inhibited chlorophyll breakdown, retarded green loss by repressing the activity and expression of chlorophyll-degrading enzymes (chlorophyllase, pheophytinase, Mg-dechelatase and chlorophyll-degrading peroxidase), and prevented massive accumulation of reactive oxygen species (ROS) (O2·- and H2O2), which mitigate browning and chlorophyll breakdown. Additionally, these treatments maintained antioxidase capacity (superoxide dismutase and ascorbate peroxidase) and antioxidant (AsA) activity at a higher level, as evidenced by the expression of their related genes in fresh-cut asparagus lettuce. In conclusion, our findings indicated that CMC-Na, AsA + L-cys, and their combination protect fresh-cut asparagus lettuce from color deterioration by regulating enzymatic browning, chlorophyll metabolism, and ROS stress. The results provide a possible method for delaying color deterioration of fresh-cut produce.

Highly Efficient Tin Perovskite Solar Cells via Suppressing Superoxide Generation

Power conversion efficiency (PCE) and stability of tin perovskite solar cells (TPSCs) are major concerns in developing lead‐free photovoltaics. Photovoltaic performance of TPSCs often suffers from the oxidation of Sn2+, organic degradation, and ion migration, which inevitably cause plenty of trap states and render inferior device parameters. Herein, a natural ascorbic acid is first introduced for high‐performance TPSCs as a multifunctional reductant to suppress the oxidation of Sn2+ and regulate trap states accordingly. Interestingly, it is found that the ascorbic acid reduces Sn4+ to Sn2+ by CC double bonds and forms a complex with Cs0.05FA0.95SnI3 perovskites via strong hydrogen bonding interactions. By virtue of theoretical calculations, the mechanism of the ascorbic acid role is further clarified. Apart from effective passivation and suppressing trap density, a superoxide interaction between perovskite and ascorbic acid is proposed. The existence of ascorbic acid successfully improved the energy barrier for O2 − generation. As a result, a significantly improved PCE from 8.95% to 13.32% is achieved for Cs0.05FA0.95SnI3 TPSCs with 0.5% ascorbic acid incorporation under AM 1.5 G illumination. In addition, our devices maintain 90% value of initial PCE after 500 h storage.

In Vitro Prevention of Browning in Persian Walnut (Juglans regia L.) cv. Sulaiman

The present investigation was undertaken to standardize the media and the anti-browning regime in order to minimize the phenolic browning of an in vitro culture of Persian walnut cv. Sulaiman. The experiments involved two types of explants, forced and unforced shoot tips, two types of media, Driver and Kuniyuki Walnut (DKW) medium andMurashige and Skooģs (MS) medium, and three types of anti-browning agents, namely, Polyvinylpyrrolidone, ascorbic acid and activated charcoal at 150, 350 and 550 mg/L each. The investigation was replicated thrice under a completely randomized design. Forced shoot tips of cv. Sulaiman on DKW medium showed the best performance in terms of least browning (13.6 ± 10.5%) and highest survival percentage of explants (74.5 ± 2.4%) when treated with ascorbic acid at 550 mg/L. However, unforced shoot tips in MS medium did not perform well and manifested maximum browning (52.9 ± 5.2%). Based on the results, we conclude that incorporation of ascorbic acid in the DKW medium significantly reduced the media and explant browning, thus, it could set the basis of successful in vitro-propagation of walnuts.

Ascorbic acid assisted synthesis of fluorescent PEG for bioimaging application

Highly fluorescent Polyethylene glycol (PEG) was synthesized with the incorporation of ascorbic acid. With a facile synthesis induced by heating, PEG molecule was furnished with its fluorescent property along with its ingrained virtues of being biocompatible and biodegradable. The ascorbic acid modified PEG (FLPEG AA) demonstrated a red shift in the fluorescence and further optimization with the ascorbic acid concentration in the system, highly fluorescent nanoparticles were elicited for the application of cancer cell imaging. In addition, with the preliminary studies, we attempted to deduce the effect of different types of materials such as polymers (PVP) and metals (Gold NPs) towards the fluorescence property of the PEG AA.

Incorporation of ascorbic acid in chitosan-based edible coating improves postharvest quality and storability of strawberry fruits

Recent postharvest studies have shown that adding an antioxidative agent in a polysaccharide-based edible coating reduces postharvest losses and extends the shelf life of a coated fruit. Therefore, the effect of addition of ascorbic acid (AA, 1%) in chitosan-based coating (CH, 1%) on strawberry fruits under cold storage conditions at 4 ± 1 °C and 85 ± 5% RH was investigated for 15 days. It was observed that addition of AA in CH coating reduced weight loss, decay percentage, malondialdehyde content and hydrogen peroxide compared to CH alone. The combined CH + AA application also suppressed fruit softening by reducing cell wall degrading enzymes (i.e. polygalacturonase, cellulase and pectin methyl esterase) activities. In addition, AA incorporation catalyzed ROS scavenging enzymes (i.e. ascorbate peroxidase, catalase, peroxidase and superoxide dismutase) activities. CH + AA treatment also maintained fruit quality by conserving higher total soluble solids, titratable acidity, ascorbic acid content, total phenolics and antioxidant activity. Sensory quality (color, taste, glossiness and overall acceptability) of fruits coated with CH + AA treatment was also stable during storage. Conclusively, the combined CH + AA application is an effective approach to maintain the postharvest quality of strawberry fruits under cold storage.

Inhibitory effect of the Ascorbic Acid on photodegradation of pharmaceuticals compounds exposed to UV-B radiation

The inhibitory effect of Ascorbic Acid (AA) on some pharmaceuticals compounds most commercialized in Chile when are exposed to the UV-B radiation was studied. The Nonsteroidal Anti-inflammatory Drugs (NSAIDs) paracetamol, ibuprofen, and ketoprofen, the fluoroquinolones ciprofloxacin and moxifloxacin and the statin atorvastatine were tested using plasma concentrations. The pharmaceutical solutions without and with AA were irradiated with irradiation dose of 216μW cm−2 and its constant and percentage of photodegradation was determined. The results showed that the most of the pharmaceuticals solutions are unstable to UV-B radiation, with the exception of paracetamol, which remained stable after 120 minutes of irradiation. The ketoprofen and ciprofloxacin solutions were the most unstable, reaching a 100 % of photodegradation. The incorporation of AA decreases the percentage and photodegradation constant in all pharmaceuticals solutions. The inhibitory effect on UV-B radiation produced by the AA, can be due to the ability of this vitamin of act as screener or UV light absorbers or react with free radicals and reducing reactive oxygen species, which would cause the structural degradation of drugs.

Degree of Conversion of Two Universal Adhesives Incorporated with Ascorbic Acid Coated Superparamagnetic Nanoparticles Assessed by FTIRDegree of conversion, universal adhesives, Superparamagnetic Fe3O4nanoparticles, FTIR analysis

Aims: To prepare and characterize a nano-ferro fluid of ascorbic acid coated superparamagnetic Fe3O4nanoparticles and incorporate them into two universal dental adhesives to test their effect on the immediate and 24-hours post-cure Degree of Conversion (DC) in comparison to their control non-incorporated adhesives. Study design: An invitro study.Methods and Material: A colloidal nano ferro fluid of ascorbic acid coated superparamagnetic nanoparticles was prepared and characterized by transmission electron microscopy and incorporated into two universal adhesives. Thirty-two adhesive samples in PotassiumBromide (KBr) discs were prepared for FTIR analysis, and distributed as following, i.e., GI: Eight adhesive samples of non-incorporated All Bond Universal (Control), GII: Eight adhesive samples of 2%-incorporated All Bond Universal, GIII: Eight adhesive samples of non-incorporated Prime&Bond Universal (Control), GIV: Eight adhesive samples of 2%-incorporated Prime&Bond Universal.Equal amount (25μL) of each adhesive was placed on KBr disc, the solvents was evaporated by a gentle steam of air, and then a second KBr disc was mounted over the first one and pressed softly to form a thin adhesive film. Finally, the KBr discs containing the adhesive were placed in the demountable cell holder and mounted into the sample chamber of the FTIR spectrometer. FTIR spectra was then recorded for each adhesive before, immediately after, and 24-hours post-curing to calculate the degree of conversion.Statistical analysis used: Statistical analysis was conducted using independent variable t-test by the IBM-SPSS software version 22.Results: The study results showed good DC values for the incorporated adhesives with no statistically significant differences in the degree of conversion values (i.e. Immediate and 24-hours post-cure) in comparison to control groups for both adhesives. The Prmie&Bond universal (Both control and incorporated) revealed significantly higher DC than All bond universal.Conclusions: Incorporation of ascorbic acid coated Fe3O4nanoparticles at 2% by mass into the universal adhesives resulted in good degreeof polymerization with no significant difference in comparison to their commercial controls.

Influence of ascorbic acid and α-tocopherol on the autoxidation and in vitro antifungal activity of amphotericin B.

Background and Purpose: Amphotericin B (AmB) is the standard treatment for systemic fungal infections; however, the formation of reactive oxygen species reduces the efficacy and stability of this molecule. The present study aimed to evaluate the effect of the combination of AmB with ascorbic acid and α-tocopherol on its autoxidation and antifungal activity.Materials and Methods: The antifungal activity against Candida albicans was evaluated by the viable cell counting method and checking their morphological changes with a scanning electron microscope. Monomer state of AmB was assessed by scanning the UV absorbance in the range of 300-450 nm and the lipid peroxidation was measured using quantification of thiobarbituric acid reactive-substances (TBARS).Results: Based on the findings, the addition of ascorbic acid (3×102 µg/mL) and α-tocopherol (16 µg/mL) to the reaction medium of AmB increased its antifungal activity while maintaining its molecular stability. Moreover, the level of TBARS formed in the reaction medium of AmB was significantly reduced after combination with ascorbic acid and α-tocopherol.Conclusion: Given their availability, their anti-free radical activity, and their low toxicity, the incorporation of ascorbic acid and α-tocopherol into the reaction medium of AmB seems to be a promising approach to obtain an effective antifungal formulation.

Antioxidant packaging material supplementary to N2-flushed modified atmosphere packaging to preserve powdered infant formula

Abstract Antioxidant Al-laminated films were fabricated with incorporation of ascorbic acid or tocopherol at 0.3 % into the food-contact polyethylene layer. These films were tested in oxygen and water vapor transmissions under the state of N2-filled pouch and then submitted to packaging 200 g of powdered infant formula under modified atmosphere of N2 gas. The addition of ascorbic acid or tocopherol into the film reduced the apparent O2 transmission rate of the sealed pouch, probably due to O2-scavenging activity, but increased the transmission rate of water vapor through the sealing. Tocopherol-loaded film allowed the highest ingress of oxygen into the infant formula package during storage at 30 °C resulting in the highest increase of peroxide value, an indicator of product lipid oxidation. The adverse effect of the tocopherol-added film pouch is thought to have been caused by the compromised oxygen barrier of sealing during extended storage. Packaging the powdered infant formula in an ascorbic acid-added film pouch under N2 flushing could work as significant supplementary tool helpful to additionally suppress lipid oxidation. Other quality indexes of pH, acidity and bifidobacteria count did not change significantly during storage for all the treatments.

Antibacterial tragacanth gum-based nanocomposite films carrying ascorbic acid antioxidant for bioactive food packaging

Food packaging has a pivotal share to improve protection, safety and shelf-life time of foods and bioproducts. Herein, we prepared bioactive nanocomposite films that composed of tragacanth (TG), polyvinyl alcohol, ZnO nanoparticles (NPs) and ascorbic acid (AA) using glycerol as a plasticizer and citric acid as a cross-linker for food packaging. The SEM images showed a homogenous distribution of ZnO NPs with low aggregation in nanocomposite films. The water solubility of nanocomposite films reduced from 15.65 % to 10.81 with increasing of TG and ZnO NPs contents. The incorporation of AA and ZnO NPs into nanocomposite films improved antioxidant activity from 50 % to 66 % in 95 % ethanolic solution. Also, the nanocomposite films showed good antibacterial activity against Gram-negative and –positive bacteria. Soil degradation rate of nanocomposite films increased from 80 % to 91.46 as the wt% of TG increased. Therefore, prepared nanocomposite films could be employed as a promising candidate for food packaging applications.

Ascorbic acid and calcium uptake in pineapple tissue through different sucrose concentrations of impregnation solution

Incorporation of ascorbic acid and calcium in pineapple slices through impregnation processes in isotonic (∼14 °Bx) and hypertonic (50 °Bx) aqueous solution of sucrose was studied. Changes in water content, soluble solids, pH, mechanical and structural properties, ascorbic acid and calcium content in fruit in function of dipping time and impregnation syrup concentration were evaluated. Isotonic treatment was more effective than hypertonic treatment for the calcium and ascorbic acid incorporation in the plant tissue. Under same conditions, the ascorbic acid uptake was greater than calcium uptake. The fruit firmness was reduced during isotonic treatment and increased by osmotic dehydration, without significant effect of the nutrients addition to the impregnation solution. Additionally, changes in some physicochemical properties of impregnation solution in function of the time have been studied. Nutrient content in impregnation solutions did not register significant changes, which would allow its reuse with some conditioning of the soluble solids concentration.

Spectroscopic Investigation of the Mixture of Ascorbic Acid and Sodium Benzoate

UV spectroscopy was employed to understand the possible interaction between ascorbic acid (AA) and sodium benzoate (SB). The absorbance of each of the preservatives was taken singly (285 and 291nm for SB and AA, respectively) and the spectrum of a common drink that contained the two preservatives was recorded. Then the interaction of AA with SB was monitored by varying the concentration of AA in SB, reaction temperature and exposure to sunlight. The peaks of AA and SB disappeared and a new peak emerged at higher wavelength upon addition of AA to SB, suggesting a redshift and incorporation of AA in SB. Sunlight and temperature (≤body temperature) did not cause AA and SB to react or changes in the wavelength of maximum absorbance. Addition of AA into a typical fizzy drink did not result in new peak suggesting AA did not create any new products by its addition to this product, which already contained AA and SB at the recommended level. However, the addition of a higher amount of AA into the fizzy drinks cause a noticeable red shift from 287.5 to 295nm. Thus caution should be taken when taking AA with SB containing products.

Biopolymer/candelilla wax emulsion films as carriers of ascorbic acid – A comparative study

The comparative studies were performed in order to assess the most suitable matrix polymer for ascorbic acid (AA). The antioxidant (0.5, 1.0, 2.0% w/w) was included into sorbitol-plasticized emulsion films based on different biopolymers: carboxymethyl cellulose (CMC), oxidized potato starch (OPS), soy protein isolate (SPI), and gelatin (GEL). AA reduced the mechanical strength of the films in a concentration dependent manner. GEL and CMC produced films with higher mechanical strength and stiffness compared to the plant storage polymers. The moisturizing action of AA inhibited plasticizer recrystallization in the protein-based films. It was found, that non-enzymatic browning of the films prepared at lower pH values (OPS and GEL) was slower than those of casted at higher pH (CMC and SPI). SPI films displayed the most intensive browning development. The highest AA retention was achieved in OPS films, while the lowest in GEL films. The AA stability increased with increasing AA concentration. A significant correlation existed between the antioxidant activity of films and the concentration of AA released into aqueous food simulant. CMC films, due to rapid dissolution, tended to have the highest ferric reducing antioxidant power (FRAP) and antiradical activity. In turn, water-swollen GEL films had the lowest antioxidant activity. Prolonged testing in an emulsified linoleic acid model system revealed that at higher AA incorporation levels the films did not differ in their anti-lipid peroxidation capacity.

Rice starch active packaging films loaded with antioxidants—development and characterization

Active antioxidant food packaging films were developed by the incorporation of ascorbic acid (AA) and butylated hydroxytoluene (BHT) into a rice starch–glycerol matrix. BHT significantly improved the water resistance of starch films. Both AA and BHT promoted significant increase in the elastic modulus but a decrease in film stretchability. S/G/BHT film presented significant decrease in water vapour permeability. AA and BHT significantly affected the lightness (L) and yellow (b) color of the films with minor differences in the green (a) colour. SEM revealed smooth surface of the films. Thermal analysis showed increase in glass transition temperature and enthalpy of transition of films with the incorporation of AA and BHT. Exposure of the films to various food simulants showed that the release from the films was dependent on the type of food simulant and the antioxidant. In the aqueous food simulant, films containing ascorbic acid (S/G/AA) produced the largest release and in the fatty food stimulant S/G/BHT film presented fast release.

Photoelectrocatalytic oxidation of glucose at a ruthenium complex modified titanium dioxide electrode promoted by uric acid and ascorbic acid for photoelectrochemical fuel cells

The simultaneous presence of uric acid (UA) and ascorbic acid (AA) is first found to largely promote the photoelectrocatalytic oxidation of glucose (GLU) at an indium–tin oxide (ITO) or TiO2 nanoparticles/ITO electrode modified with [Ru(tatp)3]2+ (tatp = 1,4,8,9-tetra-aza-triphenylene) possessing good redox activity and nanoparticle size distribution. A well-defined electrocatalytic peak for GLU oxidation is shown at 0.265 V (vs. SCE) under approximate physiological conditions upon incorporation of UA and AA. The [Ru(tatp)3]2+/ITO electrode exhibits attractive amperometric oxidation responses towards GLU, UA and AA, while controlled potentiostatically at 0.3 V, 0.7 V and 1.0 V, respectively, indicating high sensitivity and excellent reproducibility. On basis of the photoelectrocatalysis of [Ru(tatp)3]2+/TiO2/ITO anode, a GLU concentration-dependent photoelectrochemical fuel cell vs. SCE is elaborately assembled. The proposed free-enzyme photoelectrochemical fuel cell employing 0.1 M GLU associated with 0.01 M UA and 0.01 M AA as fuel shows open-circuit photovoltage of 0.608 V, short-circuit photocurrent density of 124.5 μA cm−2 and maximum power density of 21.75 μW cm−2 at 0.455 V, fill factor of 0.32 and photoenergy conversion efficiency of 36.65%, respectively.

Effect of iron and ascorbic acid addition on dry infusion process and final color of pumpkin tissue

In the present study, pumpkin (Cucurbita moschata Duchesne ex Poiret) was used as raw material to produce sweet food fortified with iron (Fe) and ascorbic acid (AA). A dry infusion process with a subsequent air drying was applied. Response surface methodology was performed in order to analyze the effect of Fe and AA incorporation into the formulation on: water loss (WL) and solid gain (SG) during the dry infusion process, color changes (ΔE) and the dehydration percentage during subsequent air drying process. The results showed that the presence of Fe and/or AA promoted SG and WL during the dry infusion and also, weight changes during the air drying process (PP). An increase of the color changes was also observed. In turn, it was possible to obtain predictive equations for the parameters studied. The application of edible coating based on tapioca starch on pumpkin product was also tested showing a protective effect from the pumpkin color view point.

Incorporation of Ascorbic Acid, Caffeine and Chloroquine Diphosphate in Dilutor Improves Structural and Functional Status of Frozen Semen

Incorporation of Ascorbic Acid, Caffeine and Chloroquine Diphosphate in Dilutor Improves Structural and Functional Status of Frozen Semen