Partial characterization of white cabbages (Brassica oleracea var. capitata f. alba) from different regions by glucosinolates, bioactive compounds, total antioxidant activities and proteins

Glucosinolates (GLS), antioxidative compounds, total radical scavenging activities (TRSAs) and proteins of white cabbage samples derived from different regions of Europe, collected in the spring and autumn, were studied. Glucobrassicin and sinigrin were the dominating GLS in all analyzed cabbage samples. Depending on origin, these two GLS accounted for ∼30% to ∼70% of the total. The total GLS content ranged from 3.3 to 7.7 μmol/g dw in lyophilized vegetables. Assays based on electron transfer [total phenols by Folin-Ciocalteu reagent (FCR), 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)] radical cation (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH)] were used to compare the TRSAs and the main bioactive compounds in cabbage. Total polyphenols varied from 2.4 to 4.9 GAE/g dw. The TRSAs ranged from 2.7 to 8.2 μmol TE/g dw in ABTS test and from 2.4 to 5.4 μmol TE/g dw in DPPH assay. The maximum amount of polyphenol compounds, antioxidant activity, as well as total GLS content, were recorded in Belgian cabbage harvested in the autumn and the lowest ones were found for Poland 2 cabbage harvested in the spring. In extracted and separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) proteins from cabbage leaves only in samples from England and Belgium some differences in patterns were found in the regions of 60 and 97 kDa. The calculated correlations between antioxidative potency and the abundance of bioactive compounds were highly statistically significant. This suggests that TRSA could serve as a means of standardization of natural mixtures, at least in the case of cabbage, necessary to compare results of biological studies carried out for vegetable derived samples.     

Influence of different cooking methods on color,bioactive compounds,and antioxidant activity of kale

In this study, the effects of different cooking methods on health-promoting phytochemicals and antioxidant activity of fresh kale were investigated. Results showed that water soluble phytochemicals were significantly decreased by boiling. While stir-frying gave the highest degradation ratio for all phytochemicals, and steaming gave the lowest degradation ratio. The thermal degradation ratios of ascorbic acid, total carotenoids, total chlorophylls, total flavonols, and total phenolics content after stir-frying were 54.9, 28.2, 71.0, 81.3, and 39.3%, respectively. The results showed that steaming can be considered as the best method of cooking as it preserve the bioactive compounds and the antioxidant activity.     

Antioxidant properties and bioactive constituents of some rare exotic Thai fruits and comparison with conventional fruits: In vitro and in vivo studies

The aim of this research was to investigate the bioactivity of durian, snake fruit and mangosteen, rare exotic Thai fruits. These fruits were compared among them and with conventional fruits: durian with mango and avocado, and snake fruit with mangosteen and kiwifruit in order to find the preferable diet for human consumption. The contents of polyphenols, flavonoids, flavanols, tannins, anthocyanins, ascorbic acid and carotenoids, and the level of antioxidant potential by ABTS, DPPH, FRAP and CUPRAC in different extracts (methanol, water, acetone, and hexane) were determined. The presence of polyphenols (flavonoids and phenolic acids) in the investigated samples was characterized by Fourier transform infrared (FT-IR) spectroscopy and three-dimensional fluorimetry (3D-FL).The in vivo studies were carried out on 25 male Wistar rats, divided into 5 diet groups, each of 5. During 30 days of the experiment the rats of all 5 groups were fed basal diet (BD), which included wheat starch, casein, soybean oil, vitamin and mineral mixtures. The rats of the Control group were fed only the BD. The BD of the other 4 groups was supplemented with 1% of nonoxidized cholesterol (NOC) (Chol group), 1% of NOC in each group and 5% of lyophilized fruits: durian (Chol/Durian), snake fruit (Chol/Snake), mangosteen (Chol/Mangosteen). After the experiment diets supplemented with exotic fruits significantly hindered the rise in plasma lipids and hindered the decrease in the plasma antioxidant activity. In conclusion, the contents of bioactive compounds and the antioxidant potential are relatively high in the studied fruits and varied among them depending on the extraction procedure. FT-IR and 3D-FL can be used as additional tools for identification and comparison of bioactive compounds. Supplementation of diets with exotic fruits positively affects plasma lipid profile and antioxidant activity in rats fed cholesterol-containing diets.     

Soymilk phenolic compounds,isoflavones and antioxidant activity as affected by in vitro gastrointestinal digestion

The aim of this research was to evaluate changes in the phenolic compounds, isoflavones and antioxidant activity of soymilk following in vitro gastrointestinal digestion (including dialysis). Gastric digestion significantly influenced the release of bioactive substances from the soymilk matrix, increasing the concentration of total phenolic components (35% as the sum of individuals and 14% by Folin–Ciocalteu [F–C] method), total isoflavone content (22%) and total antioxidant activity (76%). The concentration of all those compounds was reduced significantly in the duodenal fraction in comparison to gastric digestion and their lowest concentration was observed in the dialysed fraction, where phenolic acids were not detected. The bioaccessibility of soymilk phenolic compounds was 15% as the sum of individuals and 20% by F–C assay; isoflavones 36% and constituents with antioxidant activity 27%. Results suggest that most of these compounds were sufficiently available to be absorbed and could contribute health benefits.     

Chemical composition and antioxidant activity of dried powder formulations of Agaricus blazei and Lentinus edodes

Several mushroom species have been pointed out as sources of antioxidant compounds, in addition to their important nutritional value. Agaricus blazei and Lentinus edodes are among the most studied species all over the world, but those studies focused on their fruiting bodies instead of other presentations, such as powdered preparations, used as supplements. In the present work the chemical composition (nutrients and bioactive compounds) and antioxidant activity (free radical scavenging activity, reducing power and lipid peroxidation inhibition) of dried powder formulations of the mentioned mushroom species (APF and LPF, respectively) were evaluated. Powder formulations of both species revealed the presence of essential nutrients, such as proteins, carbohydrates and unsaturated fatty acids. Furthermore, they present a low fat content (<2 g/100 g) and can be used in low-calorie diets, just like the mushrooms fruiting bodies. APF showed higher antioxidant activity and higher content of tocopherols and phenolic compounds (124 and 770 μg/100 g, respectively) than LPF (32 and 690 μg/100 g). Both formulations could be used as antioxidant sources to prevent diseases related to oxidative stress.     

Evaluation of in vitro antioxidant properties of some traditional Sardinian medicinal plants: Investigation of the high antioxidant capacity of Rubus ulmifolius

The antioxidant capacities of 11 botanical species used in the tradition of Sardinia as teas beverages or as decoction for medicinal purposes were evaluated using different in vitro methods (BR, TEAC, DPPH and FC). Among the various species, Rubus ulmifolius, resulted the more active with all the used methods. Phytochemical investigation on the extract yields in the isolation of several phenolic compounds namely caffeic acid, ferulic acid, quercetin-3-O-glucuronide, kaempferol-3-O-glucuronide, kaempferol-3-O-(6″-p-coumaroyl)-β-d-glucopyranoside, kaempferol-3-O-(6″-caffeoyl)-β-d-glucopyranoside, chlorogenic acid, 4-caffeoylquinic acid and 5-caffeoylquinic acid. The antioxidant activity of isolated compounds was also evaluated.     

Phenolic profiles,antioxidant activity and in vitro antiviral properties of apple pomace

Methanolic and acetonic extracts of apple pomace were evaluated for phenolic profiles, antioxidant properties and antiviral effect against herpes simplex virus type 1 (HSV-1) and 2 (HSV-2). Acetone extraction yielded the higher amounts of phenolic compounds. The extraction method influenced the phenolic composition although antioxidant activity correlated weakly with phenols concentration. Among the polyphenols analysed, quercetin glycosides were the most important family, followed by dihydrochalcones. Apple pomace extracts were able to inhibit both HSV-1 and HSV-2 replication in Vero cells by more than 50%, at non-cytotoxic concentrations. Selectivity indexes (SI) ranged from 9.5 to 12.2.     

Drying of persimmons (Diospyros kaki L.) and the following changes in the studied bioactive compounds and the total radical scavenging activities

Fresh persimmons were subjected to two different processes: sun-drying during 1 month and dehydration at 60 °C during 12 h. To assess the effect of this process on nutritional and health-related properties of persimmons dietary fibers, minerals, trace elements, polyphenols and the total radical scavenging activities (TRSAs) were determined before and after processing. It was found that the contents of dietary fibers, minerals and trace elements in fresh and dried persimmons fruits were comparable. Total polyphenols in fresh persimmons was higher than in dried fruits (1.3 vs. 0.9 and 0.8 mg/100 g FW, respectively) and percentage of inhibition was higher than in dried fruits (70% vs. 59% and 55% and 58% vs. 53% and 46% for 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) [ABTS] radicals, respectively (P>0.05 in all cases). In conclusion: (1) the differences in the contents of dietary fibers, minerals and trace elements in fresh and dried persimmons are not significant; (2) the contents of polyphenols and the level of the TRSA are higher in fresh persimmons than in dried fruits; however, both variables are also high in dried persimmons; (3) when fresh fruits are not available, proper dried persimmons could be used as a valuable substitute.     

Influence of processing on the antioxidant capacity and bioactive compounds in jellies from different blackberry cultivars

The effect of thermal processing and the berry cultivar has been the subject of several studies, to serve as a basis for the least possible loss of bioactive compounds and antioxidant capacity. In Brazil, there are numerous blackberry cultivars under cultivation, and in this context, the aim of this work was to study how the bioactive compound contents and antioxidant capacity of blackberry jelly were influenced by the cultivars (Guarani, Brazos, Comanche, Tupy, Cherokee, Caingangue and Choctaw). Analysis was made of 7 fresh blackberry cultivars and 7 blackberry jelly formulations. Analysis of antioxidant activity, total phenolics, total anthocyanins and ascorbic acid was performed. It was verified that the contribution of the heat sensitive antioxidants compounds is considerable in all blackberry cultivars, and the degradation of these compounds was significantly different between the different blackberry cultivars. The Brazos and Caingangue cultivars stand out as undergoing the lowest losses in processing, resulting in jellies richer in bioactive compounds and higher antioxidant capacity.     

The antioxidant activity of selected cruciferous vegetables subjected to aquathermal processing

Kale (Brassica oleracea var. Acephala), broccoli (Brassica oleracea var. botrytis italica), Brussels sprouts (Brassica oleracea L. var. gemmifera) and green and white cauliflower (Brassica oleracea var. botrytis) were used to determine their contents of antioxidising agents: vitamin C, carotenoids and polyphenols. The examined vegetables were found to contain between 40.6 and 107 mg/100 g FW of vitamin C, from 0.04 to 2.7 mg/100 g FW of carotenoids, and from 144 to 773 mg/100 g FW of polyphenols. Cauliflower was found to contain the smallest amount of these compounds and kale the largest. The antioxidant activity of the vegetables was determined on the basis of their ability to extinguish the ABTS free radical. The aquathermal processes to which the vegetables were subsequently subjected reduced their antioxidant activity, mainly due to escape of vitamin C and polyphenols into the water environment. These losses were largest in the case of leafy or highly fragmented vegetables.     

In vitro antioxidant activity and in vivo anti-fatigue effect of loach (Misgurnus anguillicaudatus) peptides prepared by papain digestion

The in vitro antioxidant activity and in vivo anti-fatigue activity of loach peptide (LP) were determined. Results showed that LP contained the amino acids, which were expected to contribute to its antioxidant and anti-fatigue activities. LP could scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) (IC₅₀ 17.0 ± 0.54 mg/ml) and hydroxyl radicals (IC₅₀ 2.64 ± 0.29 mg/ml). It could chelate cupric ion and inhibit the lipid peroxidation in a linoleic acid emulsion system. It also prolonged the swimming time to exhaustion of mice by 20–28% compared to the control. It increased the levels of blood glucose (28–42% increase) and liver glycogen (2.3–3.0-fold increase). It decreased the levels of lactic acid and blood urea nitrogen by 10.9–27.5% and 8.6–17.5%, respectively. It also improved the endogenous cellular antioxidant enzymes in mice by increasing the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px). Therefore, LP can increase an endurance capacity and facilitate recovery from fatigue.     

Comparison of in vitro digestion characteristics and antioxidant activity of hot- and cold-pressed peanut meals

Due to the poor protein solubility, hot-pressed peanut meal (HPM) has less value than cold-pressed peanut meal (CPM) in the food industry. The objective of this study was to determine whether the denatured proteins in HPM were suitable for hydrolysis by digestive enzymes. The hydrolysis characteristics and antioxidant activity of HPM and CPM during in vitro digestion were compared. The results showed that HPM was hydrolysed more extensively than CPM. There were more free amino acids and small peptides with MW < 5 kDa in HPM hydrolysates. In addition, HPM hydrolysates displayed stronger 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,20-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical-scavenging activities, ORAC value and reducing power than CPM hydrolysates, which could be due to the higher content of small peptides, antioxidative amino acids and melanoidins in HPM hydrolysates. The above results indicated that HPM was a potential source of protein supplement for human consumption.     

Effect of storage on the bioactive compounds and antioxidant activity of quince nectar

The changes of bioactive components and antioxidant activity of quince nectar were determined during 9 months of storage at 5, 20, 30 and 40 °C. The amount of total phenolics, flavonoids and antioxidant activity was significantly declined during storage at all temperatures. Loss of L‐ascorbic acid at 5, 20, 30 and 40 °C was 32.08%, 43.69%, 65.21% and 88.82%, respectively. L‐ascorbic acid degradation was in accordance with the first‐order reaction kinetics, and activation energy was found as 43.65 kJ mol^?1. After 9 months of storage, Hydroxymethylfurfural (HMF) contents of quince nectars were 15.01, 16.64, 21.69 and 57.89 mg kg^?1 at 5, 20, 30 and 40 °C, respectively. HMF accumulation fitted a zero‐order kinetic model, and activation energy was found as 88.30 kJ mol^?1. A significant correlation was found among L‐ascorbic acid, total phenolics, flavonoids and antioxidant activity.     

Comparison of bioactive compounds,antioxidant and antiproliferative activities of Mon Thong durian during ripening

The aim of this investigation was to compare the bioactive and nutrient compounds, fatty acids, and antioxidant and antiproliferative activities of Mon Thong durian at different stages of ripening. It was found that the total polyphenols, flavonoids, flavanols, ascorbic acid, tannins and the antioxidant activity determined by four assays (CUPRAC, DPPH, ABTS and FRAP) differed in immature, mature, ripe and overripe samples. The content of polyphenols and antioxidant activity were the highest in overripe durian, flavonoids were the highest in ripe durian, and flavanols and antiproliferative activity were the highest in mature durian (p < 0.05). FTIR spectra of polyphenols, HPLC profiles of fatty acids, the antioxidant and antiproliferative activities can be used as indicators to characterise different stages of durian ripening.     

Quantification of the polyphenolic fraction and in vitro antioxidant and in vivo anti-hyperlipemic activities of Hibiscus sabdariffa aqueous extract

In the present study the quantification of the polyphenolic fraction, anthocyanins and other polar compounds, the antioxidant capacity and the anti-hyperlipemic action of the aqueous extract of Hibiscus sabdariffa has been achieved. Seventeen compounds were successfully quantified either by HPLC-DAD or HPLC-ESI-TOF-MS. Six of them were directly quantified by their corresponding standards, whereas the rest were indirectly quantified as equivalents using standards of similar compounds. The antioxidant capacity have also been estimated by comparing different assays, i,e, Trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and measurement of thiobarbituric acid reacting substances (TBARS). H. sabdariffa showed high reducing capacity in FRAP assay and significant capability to scavenge peroxyl radicals in the ORAC assay. Nevertheless, the extract exhibited poor efficacy to inhibit peroxyl radicals in lipid systems. The plant extract also exhibited the capacity to decrease serum triglyceride concentration on hyperlipemic mouse model.