Highest Values Of Antioxidant Activity Research Articles

Effect of Alginate and Chitosan Edible Coating Enriched with Olive Leaves Extract on the Shelf Life of Sweet Cherries (Prunus avium L.)

Edible film coatings are widely used as a protective barrier for the reduction of transpiration and respiration, therefore reducing the ripening process in fruits and vegetables and improving their quality. The influence of chitosan 1% and alginate 3% enriched with olive leaves extract (OLE) on the quality of sweet cherries was studied. Overall, the ripening process and the increase in anthocyanins were found to be delayed with the use of coating particularly those composed of chitosan in combination with OLE. Ascorbic acid and total phenolic contents were recorded with restricted loss at the end of 20 days of storage in both chitosan- and alginate-coated samples enriched with OLE. Higher values of antioxidant activity expressed as the percentage inhibition of DPPH were reported in correlation with phytochemical content. It could be concluded that chitosan and alginate coating enriched with OLE could be efficient for prolonging the shelf life of sweet cherries.

Determination of drying kinetics, some physical, and antioxidant properties of papaya seeds undergoing microwave vacuum drying

AbstractThe effects of microwave power (MP, 100–600 W) on the drying kinetics, as well as the physical and antioxidant properties of papaya seeds dried under microwave vacuum drying (MVD) were investigated. The results found that moisture diffusivity increased in the order of 10−8 with an increase in MP. Shrinkage increased from 1.2 to 4.9% and bulk density decreased from 3,441 to 1,091 kg/m3, respectively, while the moisture content decreased. The antioxidant contents of all of the MVD samples were higher than those of the samples dried under ambient air ventilation. An increase in MP decreased the total phenolic content from 14.69 to 10.66 mg gallic acid equivalent per gram dry weight (DW), increased both the β‐carotene and the total flavonoid content in the ranges of 0.2–0.35 mg β‐carotene equivalent per gram DW and 20.71 to 23.51 mg catechin equivalent per gram DW, respectively. Higher values of antioxidant activity were obtained at higher MP. The results have shown that the use of novel MVD technique in appropriate conditions can improve the overall drying efficiency and enhance the total yield of antioxidant content.Practical ApplicationsPapaya seeds have great potential for use as a source of antioxidants. However, the best novel techniques for retaining high values of antioxidant compounds, and therefore recouping value from the wasted seeds, has not been widely reported on. This study has found that combined microwave vacuum drying (MVD) is a very beneficial drying method for the preservation of antioxidant content. A better antioxidant yield from dried papaya seeds was obtained using MVD at a higher MP of 600 W. Trolox equivalent antioxidant capacity of seeds dried using MVD was 27.62% higher than the samples dried using ambient air ventilation.

Comparative study of some bioactive compounds and their antioxidant activity of some berry types

Berries are wealthy in bioactive compounds like phenolic compounds and flavonoids that are deemed antioxidants and are great important to health. This research was performed to examine, recognize and compare bioactive compounds in certain types of berries and their antioxidant activity. The data show that blue berry, black berry and Egyptian black mulberry contain the highest content of most bioactive compounds such as phenolic compounds, flavonoids and tannins, while long mulberry and red currant berry have the lowest content for most of these compounds. They therefore, contain the highest value of antioxidant activity. The chemical composition of the berries varies depending on cultivar, variety, location of growth, environmental conditions and harvest time, as well as post-harvest treatments therefore the composition differed from berry fruit to another. Thus, berry fruits are very useful in nutrition to protect the body from many diseases because of its containment of these compounds, which act as free radicals scavenger that harm the body and thus rid the body of many harmful toxins.

Hydrogel-based Chlorella vulgaris extracts: a new topical formulation for wound healing treatment

Chlorella vulgaris is a microalga which contains a variety of bioactive compounds. Chlorella has been used in different fields for several years and proved attractive to the pharmaceutical and cosmetic industry. The present study aimed to evaluate the wound-healing activity of a hydrogel-based C. vulgaris extract in in vivo assay. A hydrogel formulation containing different concentrations of extracts of C. vulgaris grown under autotrophic (AE) or mixotrophic (ME) condition was developed and applied for 12 days on excisional wounds in mice. Macroscopic analyses and histomorphometric studies were performed to investigate tissue repair. Extracts were evaluated for protein concentration, phytochemical profile, hemagglutinating activity, antioxidant activity using DPPH assay, and antibacterial activity. The wound-healing assay suggested that animals treated with hydrogel containing 25% of ME exhibited a higher presence of collagen deposition, a decrease of fibroblast and inflammatory cells, strong evidence of skin appendages, and evidence of basal laminae. Results showed that ME has 1.174 mg mL−1 of total proteins and hemagglutinating activity ≥ to 248 against rabbit erythrocytes and ≥ to 224 against human type B blood. The phytochemical profile of the extract demonstrated the presence of steroids, triterpenes, saponins, and sugars. In addition, ME had the highest values of antioxidant activity (54.64%) and antibacterial activity against Klebsiella pneumoniae, Enterococcus faecalis, and Escherichia coli. This first report of a hydrogel formulation containing microalgae extracts for wound healing showed that C. vulgaris cell extracts from mixotrophic cultivation have pro-healing and anti-inflammatory properties, which accelerated the wound healing process.

Drying of olive (Olea europaea L.) leaves on a conveyor belt for supercritical extraction of bioactive compounds: Mathematical modeling of drying/extraction operations and analysis of extracts

The influence of drying conditions on the composition of supercritical extracts recovered from olive leaves was investigated. Leaves were dried on a conveyor belt and the effects of air temperature and residence time on the extraction kinetics, global yield, antioxidant activity, total polyphenols content and chemical profiles of the extracts were evaluated. Inlet air temperatures of 50, 60 and 70 °C with residence times of 180, 120 and 60 min, respectively were tested. A model based on mass and energy balances with effective heat and mass transfer coefficients fitted from experimental data was used to describe the drying process. The temperature and output moisture of the leaves were well predicted by the model. The extraction kinetics was not significantly affected by the drying conditions (air temperature and residence time), but the extraction yield was enhanced for samples dried at 50 °C/180 min whereas the higher values of antioxidant activity and phenolic contents were found at 60 °C/120 min. Sovová’s model was effective in describing the supercritical extraction of olive leaves and can be used to estimate the extraction kinetics and mass transfer coefficients.

Effect of some Herbs Essential Oils on Labneh

Labneh is one of the most popular dairy products in many Middle Eastern countries. The shelf life of labneh is short even if stored at low temperature. Therefore, chemical preservatives were used to control the activity of contaminant microorganisms. An increased awareness of the harmful chemical residues in food led to a restricted use of chemical preservatives. Recently, natural substances such as spices oil can be used to prolong the shelf life of food products, because they are antioxidant and antimicrobial agents. In the present study three essential oils namely rosemary (Rosmarinus officinalis), sage (Salvia officinalis) and cumin (Cuminum cyminum) were characterized by means of GC-MS and their antioxidant capacity were studied. Also, their antibacterial activity against pathogens E. coli, B. cereus and S. aureus was determined in vitro by wells' agar diffusion method. The results obtained revealed that the tested essential oils exhibited noticeable antimicrobial activity, where cumin showing the highest inhibition and sage the lowest. The results were completed with the study the antibacterial effect of the tested essential oils in vivo (labneh). However, the previous results obtained by in vitro assays were confirmed by in vivo experiment. In addition, three batches of labneh supplemented with different essential oils were made. No noticeable differences were observed in physicochemical properties of labneh treatments in comparison with the control one. However, labneh made with 0.05% rosemary essential oil ranked the highest value of antioxidant activity after 14 days of storage, being 20.78, while plain labneh (control) possessed the lowest figure, actually 10.8. Moreover, at the end of storage period, labneh produced with 250 mg/Kg cumin essential oil was the most preferred product by the panelists and ranked the highest total score, being 87 points.

Determination of anticholinesterase and antioxidant activities of methanol and water extracts of leaves and fruits of Chamaerops humilis L.

The present study was carried out to investigate the antioxidant activity of the water and methanol extracts of leaves and fruits extracts of Chamaerops humilis L. by using ABTS cation radicals and cupric reducing antioxidant capacity (CUPRAC). Anticholinesterase effect of the extracts was tested against both AChE and BChE using a microplate-reader assay based on the Ellman method. The methanol extracts of C. humilis leaves contained relatively higher content of flavonoids and total phenolics than those of fruits. All the extracts were found to have different levels of antioxidant activity in the systems tested. The leave extract showed the highest value of antioxidant activity, based on ABTS radical-scavenging activity, while the fruit water extract showed the highest value (0.53±0.50 µg/mL) of cupric reducing antioxidant activity. Our data indicates that both methanol and water fruit extract were active for BChE inhibition (31.65 ± 0.37 and 30.19 ± 0.56%) respectively, whereas, all leave extracts did not show any activity against BChE. The present study demonstrated that the methanol and water extracts fractions of C. humilis have different responses with different antioxidant methods. Our results suggest that the C. humilis could be used as a source of antioxidant agents and may be beneficial in the AD treatment.

Enzymatic treatment improves the antioxidant and antiproliferative activities of Adenanthera pavonina L. seeds

Abstract We evaluated the effect of enzymatic treatment by amylase, cellulase and protease on antioxidant and antiproliferative activities of Adenanthera pavonina L. seeds. The effect was evaluated by using an experimental mixture design. The results showed that the antioxidant activity of the seeds increased after the enzymatic treatment. The enzymatic treatment using protease and cellulase (1:1, v/v) showed the highest values of antioxidant activity due to the increase of phenolic compounds content, mainly phenolic acids. The antiproliferative activity of the extract obtained by optimum enzymatic treatment was evaluated. We found the antiproliferative activity against the tumour lineage of prostate (PC-3) and kidney (786–0) was improved after enzymatic treatment. This work provides information that may be useful in handling of functional foods and/or drugs, since the functional properties of seeds such as antioxidant and antitumor activities were improved by enzymatic treatment with protease and cellulase.

Antioxidant Activities Correlation Analysis of Procyanidins from China Cultivars Litchi Pericarp

Ethanol extracts of litchi pericarp procyanidins (LPPC) were purified from 7 Chinese litchi cultivars. The procyanidin contents in LPPC were ranged from 659.7 mg to 1163.2 mg grape seed procyanidins/g equivalent, while the concentrations of (-)-epicatechin, procyanidin dimmer and trimer were further investigated as well. Antioxidation and free radical scavenging activities of LPPC from different sources were evaluated and compared in vitro. The results showed that LPPC for ‘Huaizhi’ owned the highest free radical scavenging activity on hydrogen peroxide (H2O2), superoxide radical ( ) and ferric reducing; ‘Feizixiao’ exhibited the highest scavenging capacity on 2,2-diphenyl-1-picrylhydrazyl radical (DPPH·), hydroxyl radical (·OH) and lipid peroxidation, however, ‘Guiwei’ possessed the highest value of antioxidant activity based on β-carotene bleaching and ferrous chelating assay. Furthermore, the compositions of LPPC suggested positive correlations with their antioxidant activities significantly.

Nutritional quality of the epicarp and mesocarp flours of baru fruits submitted to drying

ABSTRACT Baru (Dipteryx alata Vogel) is a native tree of the Cerrado. The drying and milling process can be an alternative for the use and conservation of baru fruits. The objective of this study was to evaluate the effect of drying on the nutritional characteristics of the epicarp + mesocarp flour of baru fruits. The fruits were collected in the municipality of Santa Helena de Goiás, Goiás, sanitized and submitted to drying in an oven with air circulation at temperatures of 40, 60, 80 and 100 ºC until they had a constant mass. The analyses were performed in triplicate and the results evaluated by analysis of variance and Tukey test (p ≤ 0.05). Flours produced from dehydrated fruits had a reduction in lipid content (treatments 100 °C), energy value (60 and 80 °C), pH, soluble solids, apparent specific mass and carotenoids in relation to the control sample, and high values of acidity, antioxidant activity and total phenolics. FTIR analysis showed nutrient loss.

Some properties of ayran fortified with black carrot powder

Ayran is a traditional Turkish salty drinkable fermented product prepared by the addition of water to yogurt or by the addition of yogurt culture to standardized milk. Black carrot is well known and very rich source of anthocyanins and combining with ayran was obtained a product that is natural, nutritious and highly attractive for consumer. In this study, black carrots were dried and powdered by freeze drying method and four batches of ayrans were manufactured by adding dried black carrots powder into the milk at increasing rates. One batch was treated as a control sample without black carrot powder addition and three batches of ayrans were manufactured by adding black carrot powder at the rates of 0.25%, 0.5% and 1%. All of the samples were pasteurized at 90°C for 5 minutes. Following the pasteurization, milks were cooled to 46±1°C and then inoculated with starter culture. Inoculated milks were incubated until the pH became 4.6-4.7. Ayran samples were cooled down and 0.5% salt was added. The mixture was homogenized and filled into 200 g of cups and stored at 4oC before analyses. At the 5th and 20th minutes, the lowest antioxidant activity values were found to be 5.88% and 6.08% for control sample, while the highest antioxidant activity values were found 19.90% and 21.6% for ayran with 1% black carrot powder. Increasing concentrations of added black carrot into the milk, resulted higher antioxidant activity in ayran as determined by DPPH method (p<0.05). However, pH, dry matter, fat, protein and salt contents of the ayran samples were not influenced by black carrot powder addition (p>0.05).

Chemical constituents and antioxidant activity of Garcinia madruno (Kunth) Hammel

Leaves, epicarp and seeds of Garcinia madruno (Kunth) Hammel were extracted by percolation using consecutively n-hexane, dichloromethane, ethyl acetate, and methanol until exhaustion. Then, fractions were screened for their phenolic content (Folin-Ciocalteu method) and antioxidant properties (DPPH, ABTS, FRAP methods). The phenolic content ranged from 2404 ± 121 (hexane fraction) to 9097 ± 275 mg GAE/100 g d.w. (ethyl acetate fraction) for seeds, 2372 ± 153 (dichloromethane fraction) to 11292 ± 962 mg GAE/100 g d.w. (ethyl acetate fraction) for epicarp, and 3659 ± 180 (dichloromethane fraction) to 23510 ± 255 mg GAE/100 g d.w. (ethyl acetate fraction) for leaves. The antioxidant activity was significantly depending on the nature of the extracting solvent and the organ of the plant. The highest values of antioxidant activity were displayed for ethyl acetate and hexane fractions. For ABTS assay, ethyl acetate fraction reached 57069 ± 1350, 67768 ± 2990, and 377848 ± 6039 mg AAE/100 g d.w. for seeds, epicarp, and leaves, respectively. From the most active fractions (ethyl acetate and hexane), three compounds were isolated by chromatographic techniques and their structures were elucidated by spectroscopic methods corresponding to the biflavonoids morelloflavone and volkensiflavone (from ethyl acetate fraction); and the polyisoprenylated benzophenone garcinol (from hexane fraction), first time reported in this species. These metabolites were quantified by high performance liquid chromatography and their antioxidant properties (DPPH, ABTS, FRAP, ORAC) evaluated. The highest concentration of the biflavonoids and the polyisoprenylated benzophenone was found in ethyl acetate and hexane, respectively. The biflavonoid morelloflavone displayed the highest antioxidant activity with 209216 ± 11723 (ABTS) and 293842 ± 22026 (ORAC) μmol Trolox/100 g. The results suggested that G. madruno might be a good source of metabolites with antioxidant activity.

Bioactive Compounds, Nutritional Traits, and Antioxidant Properties of Artocarpus altilis (Parkinson) Fruits: Exploiting a Potential Functional Food for Food Security on the Comoros Islands

Comoros Union presents a considerable biodiversity of food resources that are neglected or still not valorised, as breadfruit. This study aimed to evaluating nutritional and nutraceutical traits of Artocarpus altilis (Parkinson) Fosberg by characterizing its main bioactive compounds, nutritional traits, and antioxidant properties in order to contribute to the development of traditional and innovative uses of this species as functional food (e.g., infant flour). Bioactive compound composition, antioxidant properties, protein and sugar content, lipids, fibre, and macro- and microelements were observed in these fruits after a specific drying process. Breadfruit showed positive nutritional traits. The main identified phenolic groups were cinnamic acids (with a maximum of 51.88 ± 2.63 mg/100 gDW for chlorogenic acid) and tannins. The highest value of antioxidant activity was 6.40 ± 1.02 mmol·Fe2+/kgDW. This preliminary phytochemical investigation may provide a contribution to the identification and quantification of lead compounds responsible for traditional nutritional and therapeutic claims.

Extraction of Arctium Lappa leaves using supercritical CO2 + ethanol: Kinetics, chemical composition, and bioactivity assessments

This study reports the extraction of Arctium lappa leaves using scCO2 with ethanol as solvent (scCO2+EtOH) aiming the recovery of bioactive components. Experiments were performed varying the temperature (313.15–353.15 K), pressure (15–25 MPa), and ethanol to CO2 mass ratio in the static extraction step, where extraction yield, chemical composition, phenolic total content (TPC), antibacterial and antioxidant activity were determined. GC analysis showed diisooctyl phthalate, amyrin acetate, lupeol acetate and phytol as major compounds. It was observed the best relation between maximum yield (6.09%) and biological activities for the extract obtained at 353.15 K and 15 MPa. High values of antioxidant activity were found for the extracts obtained at 353.15 K and 15 MPa determined by the DPPH method and the phosphomolybdenum reduction method. The same extract presented the high phenolic content (35.51 mgGAE/gextract). High antibacterial activity was observed for all the extracts obtained with scCO2+EtOH against Staphylococcus aureus.

Quality control of Amazonian cocoa (Theobroma cacao L.) by-products and microencapsulated extract by thermal analysis

Cocoa (Theobroma cacao L.) and its by-products are widely used by the pharmaceutical, cosmetics and food industries because they contain secondary metabolites with high levels of antioxidants. The objective of this study was to evaluate the thermal profile of cocoa by-products extract and its microparticles, obtained by spray drying to preserve its biological activity. The thermal analyses showed that the events of greater mass loss occurred in the temperature range of 407–455 °C (oil), 370–429 °C (cocoa waste), 175–302 °C (cocoa extract), 299–314 °C (microparticles) and 239–329 °C (microencapsulated extract). Through differential scanning calorimetry analysis, it was possible to detect a positive effect on microencapsulation of the extract, an increase in the stability of the active principles and similar bands both for the spectra of the extract and microparticles. The extract obtained, despite being derived from the solid residue (waste), showed high values of polyphenols content and antioxidant activity. These results suggest that the spray drying technology employed for encapsulation of the active principles was also effective for their preservation.

Comparison of yield, fruit quality, antioxidant activity, and some phenolic compounds of white seedless grape obtained from organic, conventional, and integrated fertilization

ABSTRACTThe aim of this research was to determine the effect of three different fertilizing systems, including organic, conventional, and integrated ones, on the yield, fruit quality, antioxidant activity, and some phenolic compounds of white seedless grape. The study was carried out on several 6-year-old white seedless grapevine located in the Urmia Province (North-West Iran). The results showed that the fruit physical characteristics and yield were affected significantly by different fertilization systems. The highest yield was observed in the conventional fertilization, followed by organic and integrated systems. The leaf mineral contents were obviously dependent on the different fertilization used, whereas pH and titratable acidity were not affected. Based on our results, the highest values of antioxidant activity and total flavonoid were found in the organic and integrated fertilization systems, respectively. Also, the highest contents of total phenolic, catechin, and quercetin-3-galactoside were observed in the organic fertilization system. Overall, the highest nutritional quality and biochemical characteristics of white seedless grape were obtained in organic fertilization system, which improved antioxidant capacity by enhancing total phenolics, total flavonoids and valuable phenolic compounds.

Garlic (Allium sativum L.) - the content of bioactive compounds

Genus Allium belongs to the family Alliaceae, which contains more than 600 species. Garlic (Allium sativum L.) is the most popular food ingredient widely used all over the world. During the last few decades, garlic has received tremendous attention for their wide range of therapeutic properties and great health benefits. Garlic has possessed antibacterial, antifungal, antiparasitic, antiviral, antioxidant, anticholesteremic, anti-cancerous, and vasodilator characteristics. In this work the total polyphenols content, total sulfur content and antioxidant activity was compared and evaluated in four studied varieties of garlic (Mojmír, Lukan, Záhorský and Makoi). The analyzed samples of garlic were collected at the stage of full maturity in the area Bardejov. The total polyphenols content was measured using the spectrophotometric method of Folin-Ciocalteu agents. The total polyphenols content in studied varieties of garlic were determined in the range 612.23 mg.kg-1 (Mojmír) to 566.01 mg.kg-1 (Lukan). The total polyphenols content in garlic can be arranged as follows: Mojmír >Makoi >Záhorský >Lukan. The determination of the total sulfur content is based on dry combustion in the presence of oxygen and allows for the quantitative conversion of sulfur to SO2. Statistically significant highest level of total sulfur content was recorded in 0.638% (Mojmír) and the lowest level was in 0.421% (Makoi). According to determined values of total sulfur content the studied varieties of garlic can be arranged in the following order: Mojmír >Lukan >Záhorský >Makoi. Antioxidant activity was determined by the spectrophotometric method using a compound DPPH (2.2-diphenyl-1-picryhydrazyl). The highest value of antioxidant activity was measured in Mojmír (15.24%). The lowest level was observed in Makoi (11.73%). The antioxidant activity in garlic declined in the following order: Mojmír >Lukan >Záhorský >Makoi. In all studied samples of garlic was confirmed by the strong dependence of the total polyphenols content, total sulfur content and antioxidant activity.

Seasonal variation of antioxidant activity and phenolic content of Pseudevernia furfuracea, Evernia prunastri and Ramalina farinacea from Morocco

Abstract The present study was carried out to evaluate the effect of environmental conditions on the phenolic content and antioxidant activity of acetone extracts of thalli of Pseudevernia furfuracea (L.) Zopf, Evernia prunastri (L.) Ach. and Ramalina farinacea (L.) Ach. harvested in the Middle Atlas (MA) in Morocco during autamn, summer, spring, and winter. The antioxidant activity was performed in vitro by DPPH (2,2-diphenyl-1-picryl-hydrazyl) radical scavenging method. Total phenolic compounds and flavonoid contents of all the extracts were also determined. These extracts showed significant antioxidant activity, which varied relatively from one species to another and also depended on the season of collection. A significant relationship between the antioxidant capacity and total phenolics content was found. Higher values of antioxidant activity and polyphenols content of all species were registered in late winter and spring. The acetone extract of Pseudevernia furfuracea (L.) Zopf. showed the highest DPPH scavenging activity with IC50 = 498 ± 44 µg/mL and the highest total phenolic content (TPC = 328 ± 27 μg GAE/mg of dry extract). Our study showed that harvesting season had significant effect on phenolic content and antioxidant capacity of the studied lichen species and their harvesting should be done during spring season to achieve better antioxidant potential.

Stability of spray-dried beetroot extract using oligosaccharides and whey proteins

The properties and stability of spray-dried beetroot extract using maltodextrin (MD), inulin (IN), and whey protein isolate (WPI) as carrier agents were evaluated. The values of moisture, betalains content, and retention were 3.33–4.24%, 348.79–385.47 mg/100 g (dry-basis), and 88.45–95.69%, respectively. Higher values of antioxidant activity were observed for the treatments using WPI. The treatment with inulin alone presented higher hygroscopicity in the moisture adsorption isotherms at 25 °C and lower thermal stability when evaluating the thermogravimetric curves. When stored at 60 °C, the use of WPI alone conferred lower stability to the beetroot extract powder. In general, the simultaneous use of IN and WPI as carrier agents resulted in good stability of the beetroot extract powder, representing an opportunity for innovation in food products.

Effect of different drying methods on the essential oil yield, composition and antioxidant activity of Origanum vulgare L. and Origanum onites L.

Origanum onites and Origanum vulgare are important medicinal plants because of their flavoring, therapeutic, and preservative properties. Drying methods are important for obtaining high quality essential oil from spices. In this study, the effects of different drying processes on the essential oil yield, composition, and antiradical activity were evaluated. Plants were dried under sun light, in a ventilated shady place and in laboratory-type oven, and the oils were extracted with Clevenger type apparatus. Carvacrol and thymol were the major compounds in the essential oils of O. vulgare and O. onites, respectively. The highest oil yield and the highest antioxidant activity values were obtained from shade dried Origanum species followed by oven dried plants. The lowest essential oil yield and the lowest antioxidant activity for O. vulgare were found in fresh plants. The lowest essential oil yield, and the lowest antioxidant activity for O. onites belonged to sun dried plants. It could be concluded that essential oil yield, oil composition and antioxidant activity of both plants were greatly affected by the drying method.