DPPH Radical Scavenging Capacity Research Articles

Interaction between caffeic acid/caffeic acid phenethyl ester and micellar casein

Caffeic acid (CA) and caffeic acid phenethyl ester (CAPE) are bioactive molecules with poor solubility. We investigated the interaction between CA/CAPE and micellar casein (MC), and the physico-chemical and antioxidant properties of the complexes. Fluorescence spectroscopy analysis showed that both CA and CAPE formed complexes with MC via hydrophobic interactions. The binding constant was higher for CAPE than for CA at each temperature. The complexes were confirmed by FTIR and XRD. The secondary structure of MC was not affected by CAPE, but its morphology changed. CA/CAPE did not induce the dissociation of casein micelles. CA and CAPE increased and decreased, respectively, the bulk and tapped densities of MC. The complexes had higher thermal stability and DPPH radical scavenging capacity than free MC or CA/CAPE.

Microwave-assisted Extraction for Maximizing the Yield of Phenolic Compounds and Antioxidant Capacity from Cacao Pod Husk (Theobroma cacao L.)

Background: Extraction is an important step to obtain phytochemical compounds from natural materials. Among different extraction techniques, microwave-assisted extraction (MAE) is an advanced method with high extraction efficiency and low energy consumption. Objective: This study aimed to optimize the MAE parameters for obtaining the highest levels of phenolic compounds and antioxidant activity from cacao pod husk (CPH). Methods: The dried CPH was prepared using a microwave drying method. The CPH extract was prepared using a microwave-assisted extraction method. The powdered CPH extract was prepared using vacuum evaporation and freeze-drying methods. Phytochemical compounds and antioxidant capacity of CPH extracts were analyzed using spectrophotometric methods. Results: The optimal MAE parameters were 600 W microwave power, 5 s/min irradiation time, 30 min extraction time, and 50 mL/g solvent to sample ratio. Under these MAE parameters, total phenolic content (TPC), phenolic extraction efficiency (PEE), saponin content (SC), and DPPH radical scavenging capacity (DRSC) were achieved from the CPH to be 10.97 mg GAE/g dried sample, 76.82%, 70.10 mg EE/g dried sample, and 141.18 mg DPPH/g dried sample, respectively, which were not significantly different from the predicted values (10.38 mg GAE/g dried sample, 72.68%, 70.09 mg EE/g dried sample, and 121.49 mg DPPH/g dried sample, respectively). The residual moisture, water activity, density, water-soluble index and pH of powdered CPH extract were 9.72%, 0.38, 0.17 g/ml, 84.93% and 7.68, respectively. TPC, total flavonoid content (TFC) and SC of powdered CPH extract were 15.75 mg GAE/g dried sample, 27.03 mg CE/g dried sample and 133.67 mg EE/g dried sample, respectively. DRSC and ferric reducing antioxidant power (FRAP) of powdered CPH extract were 227.79 mg DPPH/g dried sample and 14.12 mg Fe(II)/g dried sample, respectively. Conclusion: The findings from this study reveal that the powdered extract obtained from the CPH at the optimal MAE parameters is a rich source of phytochemicals possessing great antioxidant activity. Therefore, it is a potential candidate to apply in functional foods.

Whey protein-blackcurrant concentrate particles obtained by spray-drying and freeze-drying for delivering structural and health benefits of cookies

Milk whey can interact with polyphenols leading to the formation of protein-polyphenol complexes. Whey protein isolate (WPI) was combined with blackcurrant concentrate (BC) using spray-drying (SWB) and freeze-drying (FWB) techniques. In this study, SWB and FWB were incorporated into a cookie dough, replacing 5%, 10% and 15% of flour to evaluate their effects on the physicochemical and nutritional properties of cookies. The colour and texture parameters of cookies were influenced by the amount of protein ingredients. The combination of the protein ingredients with cookies provided a higher protein and lower carbo diet option. The total phenolic contents (TPC) in SWB-enriched cookies were lower than those of the corresponding FWB-enriched cookies, but higher than the TPC of the control cookies. FWB-enriched cookies showed stronger DPPH radical scavenging capacity and reducing power than the corresponding SWB-enriched cookies before the digestion. After an intestinal digestion, FWB-enriched cookies decreased and showed lower reducing power, but higher DPPH radical scavenging capacity than the corresponding SWB-enriched cookies. FWB-enriched cookies exhibited stronger hypoglycaemic properties than SWB-enriched cookies. BC-fortified whey protein ingredients have positively influenced the functional characteristics of fortified cookies.

Optimized the Process of Enzymes Coupled with Lactobacillus plantarum and Saccharomyces cerevisiae to Ferment Ginkgo Seeds by Response Surface Methodology

This study aimed to optimize the process of enzymes coupled with Lactobacillus plantarum and Saccharomyces cerevisiae to ferment ginkgo seeds by response surface methodology,in order to obtain a kind of ginkgo fermentation powder with high antioxidant activity. The effects of solid-liquid ratio,total amount of compound enzyme,mass ratio of glucoamylase and α-amylase,enzymolysis time,total amount of mixed fermentation agent,mass ratio of Lactobacillus plantarum and Saccharomyces cerevisiae,fermentation time on soluble protein content and DPPH radical scavenging capacity of ginkgo fermentation powder(GFP)were studied by single factor experiment,and based on the DPPH radical scavenging capacity,response surface analysis was used to optimize the process conditions of Lactobacillus plantarum and Saccharomyces cerevisiae coupled with enzymes to ferment ginkgo seeds. The results showed that on the basis of adding 0.3 g/100 g of compound enzyme,enzymolysis 2 h and fermentation 12 h,the best technology of cooperation of bacteria and enzyme fermentation was as follows:1:6 of solid-liquid ratio,2:1 of glucoamylase and α amylase,3.12 g/100 g of mixed fermentation agent,1:1 of Lactobacillus plantarum and Saccharomyces cerevisiae,the DPPH radical scavenging capacity was 69.7%±1.1%,which was basically consistent with the model prediction. Compared with the untreated ginkgo powder(G),the DPPH free radical scavenging rate of Ginkgo fermentation powder(GFP)increased by 257.4%,the soluble protein content was 4.47±0.13 g/100 g,increased by 330%,the flavone content was 0.15±0.01 mg/g,increased by 50%,the polyphenol content was 2.49±0.04 mg/g,increased by 118%,the ginkgolic acid content was 2.96±0.32 μg/g,the removal rate was 85.4%. It showed that enzymes coupled with Lactobacillus plantarum and Saccharomyces cerevisiae fermentation could significantly improve the antioxidant activity of ginkgo seeds,and the contents of antioxidant components as soluble protein,flavonoids and polyphenols in the GFP were significantly increased,and the contents of toxic components ginkgolic acid was significantly decreased,which provided the material basis for the deep processing of ginkgo seeds.

Biological Activity of the Extracts from Pecan Shelling Industry Byproducts

HighlightsThe first study on characterization of the extracts obtained from industrial pecan nut processing byproducts.Chemical composition and biological activity of the extracts varied with type of byproduct and the pecan cultivars used in the process.Pecan shell extracts exhibited anticancer, antioxidant, and antimicrobial activity.Abstract. Industrial processing of pecan nuts produces large amounts of shells, which have economic significance for pecan growers and processors. Hence, it is imperative that valorization of pecan processing byproducts is explored. In this study, byproducts from commercial pecan shelling operations were evaluated as potential sources of biologically active phytochemicals. Shelling byproducts from Pawnee, Native, and Stuart cultivars were examined. Aqueous ethanol shell extracts were analyzed for their chemical composition using liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF/MS). Total phenolic content, DPPH radical scavenging capacity, anticancer activity, and antimicrobial activity of the samples were investigated. The chemical composition and biological activity of the shell extracts varied significantly with the pecan cultivar and type of byproduct stream used in the study. The presence of nut meat pieces in the byproducts resulted in high oil content in the extracts. The extract from Pawnee cultivar showed high DDPH activity, low IC50 for cancer cell lines, and high IC50 for the healthy cell line (Vero). Extracts from all cultivars had antimicrobial activity against Escherichia coli at relatively high disk loadings. This is the first study on the biological activity of extracts obtained from commercial pecan shelling byproducts. The findings of this study have significant practical implications and provide the initial data much needed for valorization of industrial pecan shelling byproducts. Keywords: Anticancer activity, Antimicrobial activity, Chemical composition, Pecan shell extract.

Variation of photosynthetic pigments and biochemical screening in some seaweeds from Eastern Harbor, Alexandria, Egypt

The current study examined the biochemical composition of four seaweeds (Ulva fasciata, Ulva compressa, Corallina officinalis, and Corallina elongate) which were collected from Eastern Harbor located at Alexandria Mediterranean coast, Egypt. Total chlorophyll content was the maximum in Ulva compressa (2.7 mg g–1 FW) and the minimum value was observed in Corallina elongate (0.90 mg g–1 FW). In comparison, the maximum carotenoids were registered in Corallina officinalis (1.04 mg g–1 FW) followed by Corallina elongate (0.86 mg g–1 FW). The lowest ratio was recorded in Ulva fasciata (0.45 mg g–1 FW). The results showed that the green seaweed (Ulva compressa) contained the highest amounts of phenols (12.7 mgGA/g dry wt.), flavonoid (9.42 mgCA/g dry wt.) and has the maximum percentage of DPPH radical scavenging capacity, Total antioxidant capacity (TAC) assay, and Total Reducing Capacity (TRC) (80.45, 12.5 and 71.6 respectively). On the other hand, the red seaweed (Corallina elongate) contained the lowest amounts of phenols (5.9 mgGA/g dry wt.), flavonoid (8.29 mgCA/g dry wt.), and has the maximum percentage of DPPH, TAC, and TRC (70.3, 8.4, and 57.8 respectively). Due to seaweed's biochemical composition, these findings recommend being used as an antioxidant agent for food supplements, cosmetics, medicinal applications, and pharmaceutical industries.

Extraction, analysis of polyphenols and antioxidant properties of morrocan barley seed extracts (Hordeum vulgare L.)

This study investigated the effect of extraction method and the choice of solvent on the phenolic substance and antioxidant activity of certain varieties of grain seeds (Hordeum vulgare L.). In this ponder, three diverse solvents were used, specifically acetone, ethanol, and methanol, and three extraction methods were utilized to extract the phenolic substance ultrasound extraction, Soxhlet, and maceration. The levels of total phenols (TPC), total flavonoids (TFC) and proanthocyanidins (PA) were decided. The results appeared that diverse solvents of different polarity had a major impact on polyphenol content and antioxidant activity; the highest TPC (1.990 mg EG/g of dried extract), PA (1.628 mg EC/g of dried extract) were obtained with acetone, the results of TPC and PA were in this order: 70% acetone extract > 70% ethanol extract > 70% methanol extract and the highest TFC (2.204 mg EQ/g of dried extract) were obtained with methanol, the results of TFC were in this order: 70% methanol extract > 70% acetone extract ≈ 70% ethanol extract. However, different extraction methods gave comparable results. In vitro antioxidant activities were assessed utilizing the DPPH radical scavenging capacity, The lowest IC50 value reflects the highest antioxidant potency, acetone extract showed the greatest ability to scavenge DPPH free radicals with an IC50 of 2.013 mg/ml, 2.024 mg/ml, 2.635 mg/ml, 3.428 mg/ml respectively observed in the varieties MASSINE, LOCALE, CASAMENCE, AMALOU, these results show that barley seeds of the two-row type (MASSINE and LOCALE) have a higher antioxidant activity compared to the six-row type (CASAMENCE and AMALOU). Ultrasonic extraction was better for extracting antioxidant molecules from barley seeds in comparison to soxhlet and maceration.

A comparison of nutritional values and antioxidant levels of desi and Turkish kabuli chickpea (Cicer arietinum L.) seeds

Chickpea has an increasing importance due to potential as a functional food. This study aimed to compare three kabuli genotypes (Gülümser, Sarı and Arda) with three desi genotypes (ICC 3996, Gaffa and ICC 12004) considering nutrients and antioxidant capacity. Therefore, nutritional values of seeds were analyzed in terms of tota l protein, carbohydrate and mineral element contents, while total phenolic and total flavonoid contents besides ABTS and DPPH radical scavenging capacities were tested to investigate antioxidant capacities. Kabuli genotypes were superior to desi genotypes considering seed weight, seed volume and hydration capacity. All genotypes except ICC 3996 were rich in protein. Despite its small seeds, ICC 3996 genotype was identified as the richest genotype according to carbohydrate content. ICC 3996 and Arda had superiority over other genotypes according to ABTS and DPPH antioxidant capacities. Sarı and Gülümser were determined to be superior to other genotypes according to phenolic and flavonoid contents. Desi genotypes were superior to kabuli genotypes considering Ca, Na, Mg, Fe and Cu contents, while Mn and Ni contents were significantly higher in kabuli seeds. The results of the study showed that all genotypes can be accepted as functional food, supported by rich nutritional values and mineral contents.

Phenolic compounds and antioxidant properties of wheat fermented with Agaricus brasiliensis and Agaricus bisporus.

Solid-state fermentation with Agaricus brasiliensis and Agaricus bisporus on whole grain wheat was carried out. Phenolic compounds and antioxidant properties of fermented wheat were determined. The results showed that the maximum values of polyphenols contents in wheat fermented with A. brasiliensis and A. bisporus reached, respectively (3.16± 0.21) and (3.93± 0.23) mg GAE/g, which were 2.90 and 3.61 times of unfermented control. By employing ultra performance liquid chromatography coupled to mass spectrometry (UPLC-MS), 18 kinds of phenolic compounds were identified from fermented wheat. Compared with control, only 4-hydroxy-benzaldehyde was the same compound. It indicated that fermentation with the two fungi changed polyphenols contents and phenolic compounds composition in wheat to a great extent. Among these phenolic compounds, except for 4-hydroxy-benzaldehyde, 4-hydroxy-benzoic acid and β-N-(γ-glutamyl)-4-formylphenylhydrazine, other 15 kinds of phenolic compounds were first identified from mushroom samples (including fruit bodies, mycelia and fermentation products). DPPH radical scavenging capacity, reducing power, ferrous ion chelating ability and inhibition of lipid peroxidation of fermented wheat were significantly stronger than control (P <0.05).

Phytochemical and Biological Studies on Bark Extract of Aporosa wallichii Hook.f.

The ethyl acetate extract of bark of Aporosa wallichii Hook.f. was extensively investigated for the chemical characterization of secondary metabolites and for biological activities. After repeated chromatographic separation and purification, two compounds were elucidated as a phenolic compound ferulic acid (1) and an uncommon triterpene glut-5(6)-en-3β-ol (2) from the ethyl acetate extract of barks of A. wallichii by using high field NMR analyses. This is the first report of isolation of both compounds from this plant species. No significant antimicrobial activity was observed for any fraction after Kupchan partitioning of the extract. During the antioxidant activity assay, the ethyl acetate soluble fraction of A. wallichii demonstrated significant DPPH radical scavenging capacity with an IC50 value of 1.25 μg/mL. The other fractions viz. petroleum ether, aqueous and chloroform soluble fractions exhibited moderate, mild, and weak activity respectively. The petroleum ether soluble fraction demonstrated maximum thrombolytic property (51.33%) which was similar to that of standard streptokinase (66.81%).&#x0D; Dhaka Univ. J. Pharm. Sci. 19(2): 139-143, 2020 (December)

Microwave‐assisted extraction for optimizing saponin yield and antioxidant capacity from cacao pod husk ( Theobroma cacao L.)

This study aimed to optimize microwave-assisted extraction (MAE) parameters for saponins from cacao pod husk (CPH). The results showed that the optimal MAE parameters for obtaining the highest saponin content (SC) and saponin extraction efficiency (SEE) from the CPH were 85% methanol concentration, 600 W microwave power, 6 s/min irradiation time, 40 min extraction time, and 50 ml/g solvent to sample ratio. Under these optimal parameters, the measured values for SC and SEE were 69.9 mg EE/g dried sample (DS) and 71.1%, respectively. The powdered CPH extract obtained under the optimal MAE parameters and freeze drying had moderately low water activity (0.52) and high water soluble index (88.58%). The powdered CPH extract possessed high saponin and flavonoid contents (402.74 mg EE/g DS and 115.50 mg CE/g DS, respectively), which displayed potent antioxidant capacity with DPPH radical scavenging capacity and ferric reducing antioxidant power of 348.67 mg DPPH/g DS and 64.88 mg Fe(II)/g DS, respectively. Therefore, the optimal MAE parameters of 85% methanol, 600 W, 6 s/min, 40 min, and 50 ml/g are recommended for extraction of saponins from the CPH for further investigation and application. Practical applications Cacao pod husk is generated a huge amount in cacao processing industry, which is considered as a potential source for exploitation of bioactive compounds, particularly saponins for application in the nutraceutical and functional foods industries. This strategy helps to increase the economic value for cacao tree as well as reduce the risk for environmental pollution, toward sustainable development.

Interrelation of cholesterol‐lowering, antioxidant activity and DNA damage protection to the different solvent extracts of mulberry (Morus albaL.)

Relationships among the cholesterol-lowering, antioxidant, and DNA damage protection activity of four solvent extracts from the Morus alba L. (Cultivar Hongguo 2) fruits, leaves, and twigs were investigated. The petroleum ether extract of fruit (FPE) had the highest amount of total flavonoids, cholesterol-lowering activity, and better DPPH radical scavenging capacity. The ethyl acetate extract of fruit (FEE) had the highest antioxidant activity. The petroleum ether extract of the leaf (LPE), fruit (FPE), and ethyl acetate extract of twig (TEE) had strong inhibiting lipid oxidation activity (ILOA) and DNA damage protection potential, accompanied with high total phenols and flavonoids content. It suggested that polyphenol contents, flavonoid contents, or both to Hongguo 2 were positively correlated with the three biological activities, moreover, the low polarity extracts of the high ILOA could improve the cholesterol-lowering activity or DNA damage protection potential through the synergism among different polyphenolic and flavonoids compounds. Practical applications All the results indicate that the medium and low polarity substances of Hongguo 2 are good sources of natural anti-hypercholesterolemia, antioxidants, and DNA damage protection deserved further investigation and process to functional food. The petroleum ether extract of the fruit (FPE) had both high cholesterol-lowering and DNA damage protection activity that could serve as potential Chinese patent medicine in a trial to alleviate the adverse effects of hypercholesterolemic individuals. The petroleum ether extract of the leaf, fruit, and ethyl acetate extract of twig with strong DNA damage protection potential and rich phenols and flavonoids could be a functional food to prevent genetic damage. The fruit ethyl acetate extract with high antioxidant activity could be a natural anti-aging ingredient to apply to antioxidation health products.

Characterisation and antioxidant activity of glycated casein hydrolysate with xylose: Impacts of zinc sulphate and cupric chloride

Impacts of zinc sulphate and cupric chloride on characteristics and antioxidant capacities of glycated products (GPs) derived from casein hydrolysate (CH) and xylose were studied. The browning degree of xylose–CH GPs was the largest at zinc sulphate addition of 15 mg L−1, while its browning degree increased with cupric chloride extended from 0 to 15 mg L−1. Loss of free amino groups, fluorescence intensity and the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging capacity of xylose–CH GPs increased with the increase of cupric chloride addition, but loss of amino groups, fluorescence intensity and DPPH radical scavenging capacity were largest at the zinc sulphate addition of 15 mg L−1. The addition of zinc sulphate and cupric chloride promoted production of higher and smaller molecular substances in xylose–CH GPs and CH. Therefore, zinc sulphate and cupric chloride promoted glycated reaction of xylose and CH and enhanced antioxidant activity of xylose–CH GPs.

Characteristics of Sunsik, a Cereal-Based Ready-to-Drink Korean Beverage, with Added Germinated Wheat and Herbal Plant Extract.

The purpose of this study was to develop a formulation of Sunsik with improved health benefits by adding germinated wheat (GW) and herbal plant extract (HPE) using a response surface methodology (RSM). The central composite experimental design (CCD) was used to evaluate the effects of Sunsik with added HPE (2–4%) and GW (10–20%) on total phenolic content (TPC), total flavonoid content (TFC), Trolox equivalent antioxidant capacity (TEAC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity, gamma butyric acid (GABA) content, total color changes (△E), browning index (BI), water absorption index (WAI), and water solubility index (WSI). As a result of the CCD, the independent and dependent variables were fitted by the second-order polynomial equation, and the lack of fit for response surface models was not significant except in relation to WSI. The GABA content, TPC, and TEAC were more adequate for a linear model than for a quadratic model, and they might be affected by GW rather than HPE. Alternatively, the TFC, DPPH radical scavenging capacity, WAI, WSI, △E, and BI were fitted with quadratic models. The optimum formulation that could improve antioxidant and physicochemical properties was Sunsik with 3.5% and 20% added HPE and GW, respectively.

Melatonin delays leaf senescence of postharvest Chinese flowering cabbage through ROS homeostasis

Reactive oxygen species (ROS) trigger and accelerate leaf senescence. Melatonin, a low molecular compound with several biological functions in plants, is known to delay leaf senescence in different species, including Chinese flowering cabbage. However, the mechanism(s) underpinning melatonin-delayed leaf senescence remains unclear. Here, we found that melatonin lowered the expression of chlorophyll catabolic genes (BrPAO and BrSGR1) and senescence-associated genes (BrSAG12 and BrSEN4), decreased chlorophyll loss, minimized the alteration in Fv/Fm ratio and remarkably delayed senescence of Chinese flowering cabbage after harvest. Moreover, the over-accumulation of O2•-, hydrogen peroxide (H2O2) and malondialdehyde contents and the expression of respiratory burst oxidase homologues (RBOH) genes (BrRbohB, BrRbohC, BrRbohD, BrRbohD2 and BrRbohE) were significantly inhibited by melatonin treatment. Melatonin-treated cabbages also showed higher O2•-, OH• and DPPH radical scavenging capacity and enhanced activities of peroxidase (POD), superoxide dismutase (SOD) and their gene expressions. Up-regulation of key components of ascorbate–glutathione (AsA-GSH) cycle, the metabolic pathway that detoxify H2O2, was also observed in melatonin-treated cabbages. These findings suggest that melatonin-delayed postharvest leaf senescence of postharvest Chinese flowering cabbage may be mediated, at least in part, by maintaining ROS homeostasis through restraining RBOHs-catalyzed ROS production and enhancing the activity of ROS-scavenging system including major antioxidant enzymes and AsA-GSH cycle.

Effect of Microwave Pretreatment of Seeds on the Quality and Antioxidant Capacity of Pomegranate Seed Oil.

Microwave pretreatment of oilseeds is a novel technique used to enhance oil nutraceutical properties. In this study, the effect of microwave pretreatment of seeds was investigated on pomegranate seed oil quality attributes including oil yield, yellowness index, refractive index, peroxide value, ρ-anisidine value, total oxidation value, conjugated dienes, total phenolic content, total carotenoids content, phytosterol composition, fatty acid composition, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity, and ferric reducing antioxidant power (FRAP). The seeds of three different pomegranate cultivars (‘Acco’, ‘Herskawitz’, and ‘Wonderful’) were microwave heated at 261 W for 102 s. Pomegranate seeds microwave pretreatment enhanced oil yield, yellowness index, total carotenoids content, total phenolic content, FRAP and DPPH radical scavenging capacity, despite an increase in conjugated dienes, and peroxide value. Palmitic acid, oleic acid, linoleic acid, saturated, and monosaturated fatty acids were increased after pomegranate seeds microwave pretreatment, whilst the levels of punicic acid and β-sitosterol were reduced. Nevertheless, the refractive index, the ratio of unsaturated to saturated fatty acid of the extracted oil were not significantly (p > 0.05) affected by pomegranate seeds microwave pretreatment. Principal component analysis and agglomerative hierarchical clustering established that ‘Acco’ and ‘Wonderful’ oil extracts from microwave pretreated PS exhibited better oil yield, whilst ‘Herskawitz’ oil extracts showed higher total carotenoids content, total phenolic content, and antioxidant capacity.

Citrus pectin modified by microfluidization and ultrasonication: Improved emulsifying and encapsulation properties

In this study, modified citrus pectin treated with a combination of microfluidization and ultrasonication was compared to the original and ultrasonication treated pectin on hydrodynamic diameter, molecular weight, polydispersity, zeta potential, apparent viscosity, Fourier-transform infrared spectroscopy (FTIR), 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical scavenging capacity, scanning electron microscope (SEM), atomic force microscopy (AFM), their emulsifying properties and encapsulation properties. Modified pectin treated with a combination of microfluidization and moderate ultrasonication (MUB) was found to have lowest hydrodynamic diameter (418 nm), molecular weight (237.69 kDa) and polydispersity (0.12), and relatively low apparent viscosity among all pectin samples. Furthermore, it showed significantly higher DPPH radical scavenging capacity than the original pectin although only slightly higher than that of ultrasonication treated one (UB). MUB showed a thin fibrous morphology and decreased degree of branching from SEM and AFM. Emulsion stabilized by MUB had highest centrifugal and thermal stability compared to emulsions stabilized by UB and the original pectin. This could be attributed to higher interfacial loading of MUB (17.90 mg/m2) forming more compact interfacial layer observed by confocal laser scanning microscopy (CLSM). Moreover, both MUB and UB exhibited improved encapsulation functionality to protect cholecalciferol (vitamin D3) from UV degradation compared to the original pectin.

Antioxidant activity and GC-MS profile of Conyza bonariensis L. leaves extract and fractions

The 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing power (FRAP), and semivolatile compounds of Conyza bonariensis L. leave extract and fractions are discussed. A methanolic crude extract was obtained through maceration, and subsequently, n-hexane, chloroform, and ethyl acetate fractions were collected using a solvent-solvent partition. Total phenols, flavonoids, and antioxidant activity assays were performed in an ultraviolet-visible (UV-Vis) spectrophotometer, and the results were expressed as Gallic Acid, Quercetin, and Trolox equivalents respectively. The findings achieved indicate that ethyl acetate fraction showed the highest DPPH radical scavenging capacity (90.69±3.16%) at 500 µg mL-1, and reduced the ferric tripyridyltriazine complex (Fe3+-TPTZ) with values between 19.68 and 2,355.37 mg Trolox equivalent (TE) g-1. It was identified 28 phytoconstituents through Gas chromatography-mass spectrometry (GC-MS). The scavenging activity of ethyl acetate fraction could be correlated mostly to the presence of eugenol, trans-isoeugenol, lucenin-2, methyl salicylate, and syringic acid. This study reveals that the ethyl acetate fraction could be used as a good source of antioxidants for health benefits.

Effect of cultivar and blanching of pomegranate seeds on physicochemical properties, nutritional qualities and antioxidant capacity of extracted oil

This study investigated the effect of cultivar and blanching of pomegranate seeds (PS) on quality attributes of the extracted oil. The quality attributes studied included oil yield, refractive index (RI), yellowness index (YI), conjugated dienes (K232), peroxide value (PV), ρ-anisidine value (AV), total oxidation value (TOTOX), total carotenoids content (TCC), total phenolic content (TPC), fatty acid composition, phytosterol composition, ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity. Three different cultivars of PS (‘Wonderful’, ‘Herskawitz’ and ‘Acco’) were blanched at 95 °C for 3 min. In each experiment, unblanched PS were used as the control. Blanching of PS improved oil yield, YI and DPPH radical scavenging capacity, while it decreased TCC, FRAP and TOTOX. The effect of blanching PS varied among the individual fatty acids and phytosterols. Interestingly, blanching of PS increased punicic acid content and the ratio of unsaturated to saturated fatty acid (UFA: SFA). The K232, RI and TPC of the oil extracts were not significantly (p > 0.05) affected by blanching. TPC was strongly correlated (r = 0.876) with FRAP. Principal component analysis established that ‘Wonderful’ and ‘Acco’ oil extracts from blanched PS were associated with oil yield, YI and β-sitosterol, whereas ‘Herskawitz’ oil extracts from blanched PS were correlated with punicic acid, FRAP and DPPH radical scavenging capacity. In conclusion, blanching ‘Wonderful’ and ‘Acco’ PS may improve oil yield, β-sitosterol content and colour, whilst blanching ‘Herskawitz’ PS may enhance the antioxidant capacity of extracted oil, which is beneficial in the cosmetic, nutraceutical, pharmaceutical and food industries.

Phytochemical profiles, antioxidant, and antiproliferative activities of red-fleshed apple as affected by in vitro digestion.

The aim of this study was to characterize the phenolic profiles in the extracts and digesta (after in vitro digestion) of different red-fleshed apple fruit parts and to assess the effects of digestion on the in vitro antioxidant capacity and antiproliferative activity. The main polyphenols were identified by UPLC-MS/MS and HPLC. Our results indicate that the digesta had less total phenolics, flavonoids, and anthocyanins, but more free phenolic acids, than the extracts. An analysis of the in vitro antioxidant capacity (including ABTS radical scavenging activity, DPPH radical-scavenging capacity, ferric reducing antioxidant power [FRAP], and cellular antioxidant activity [CAA]) revealed that the digestion decreased the ABTS, DPPH, and FRAP values, but increased the CAA values, relative to the corresponding values for extracts. These results suggest that the digestion improved the effectiveness of the phenolic substances. Moreover, our findings imply that the digestion promoted the antiproliferative activity of red-fleshed apple peels and flesh relative to the extracts. Future in vivo investigations are warranted based on the results of the current study. PRACTICAL APPLICATION: The effects of an in vitro digestion on the phenolic compounds as well as the antioxidative and antiproliferative activities of red-fleshed apple were evaluated. The resulting data may clarify the bioavailability of the polyphenols in red-fleshed apple and enable scientists and consumers to exploit natural polyphenols.