LC-ESI-MS/MS profiling and antioxidant activity of okra (Abelmoschus esculentus (L.) Moench) fruit pericarp from different accessions cultivated in Biskra, South Algeria

Inhibitory effect of raspberries on starch digestive enzyme and their antioxidant properties and phenolic composition

The objective of this study was to characterize the phenolic compounds and antioxidant activities of U.S.-produced cool season legumes. A total of 33 cool season legume samples were selected. Some common beans and soybeans were included for comparisons. Total phenolic content (TPC), total flavonoid content (TFC), and condensed tannin content (CTC) were analyzed. Ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, and oxygen radical absorbance capacity (ORAC) were used for analyzing antioxidant properties. Color of the legume flour and the seed coat was also analyzed. TPC, TFC, CTC, FRAP, DPPH, and ORAC values of legumes were significantly different not only between classes but also among samples within each class. Among cool season legume classes, lentils possessed the highest concentrations of the phenolic compounds and antioxidant activities. Colored common beans and black soybeans exhibited higher TPC, TFC, CTC, FRAP, DPPH, and ORAC values than those of yellow peas, green peas, and chickpeas. Antioxidant activities (FRAP, DPPH, and ORAC) were strongly correlated (r= 0.96, 0.94, and 0.89, respectively, P < 0.01) with TPC. TPC and ORAC were moderately correlated (P < 0.01) with either the seed hull surface color or the flour color.

Assessment and comparison of the antioxidant activities and nitrite scavenging activity of commonly consumed beverages in Korea

Background: Medicinal plants include a variety of active and helpful components, including flavonoids and phenolic compounds. As a result, they can act as powerful therapeutic agents, helping to improve the numerous processes associated with wound healing. Antioxidants are postulated to help control wound oxidative stress and thereby accelerate wound healing. Materials and Methods: Pun podi (PP) containing Datura metel (D. metel) L. fruit and sulfur as ingredients was prepared using the fruit collected in three quarters of a year. The total antioxidant capacity (TAC), total phenolic content (TPC), and total flavonoid content (TFC) were analyzed. Results: Based on the phytochemical analysis, notable distinctions (P &lt; 0.005) were noted in TPC and TFC in both cold and hot water extracts when PP was prepared from fruits collected in three quarters of a year, using three different methods. Similarly, TAC exhibited significant variations (P &lt; 0.005) in both cold and hot water extracts of PP, when prepared in three quarters of a year. Hot water extracts exhibited higher TPC, TAC, and TFC values compared to cold water extracts. The IC50 values of cold water extracts were higher than those of hot water extracts. Significant differences in 2,2-diphenyl-1-picrylhydrazyl values (P &lt; 0.05) were observed in cold (P = 0.034) and hot (P = 0.009) water extracts of PP prepared from the fruits collected in three quarters of a year, except for the hot water extract of PP 1 (P = 0.155) and 3 (P = 0.059). Conclusion: Based on the findings of this study, PP prepared with raw sulfur exhibited significantly higher TPC, TFC, and TAC values compared to other PP samples.

Total phenolic, total flavonoid distribution and antioxidant activity in skin, pulp and fruit extracts of 12 plum cultivars were investigated. The results showed that the levels of total phenolic and flavonoid compounds changed depending on cultivars and fruit parts. The total phenolic content in skin was 4.5 times higher than that in pulp and 3.2 times higher than that in the whole fruit. The total flavonoid content in skin was 18.7 times higher than that in pulp and 9.6 times higher than that in the whole fruit. As the trend observed for antioxidant activity, a positive relationship (correlation coefficient r2 = 0.83–0.92) was presented between total phenolics and total antioxidant capacity. The results confirm that plum is a good source of natural phenolic antioxidants. Practical Applications The present study indicated that plum can contribute to the dietary intake of antioxidants, depending on cultivars and fruit parts. It is among the few studies investigating the distribution of total phenolic, total flavonoids and total antioxidant capacity in the skin, pulp and fruit of plum cultivars. It was observed that the highest values of total phenolic and flavonoid content were obtained from skin extracts. The study highlighted that phenolics and flavonoids in plums may play an important role as radical-scavenging agents that could be used for a healthy human life. This fact may open new perspectives for plum – besides its traditional uses – to be used in assuring a wholesome diet and a healthy life.

Honey consumption and imports have increased in recent years, and it is considered by consumers to be a healthy alternative to more commonly used sweeteners. Honey contains a mixture of polyphenols and antioxidant compounds, and the botanical origin and geographical area of collection play an important role on its chemical composition. The present study investigated the physicochemical properties, total phenolic content and antioxidant capacity of Spanish thyme honey and chestnut honey, and their mixtures with royal jelly (2% and 10%) and propolis (2% and 10%). The analysis of the physicochemical parameters of both honey samples showed values within the established limits. Propolis showed the highest value of total phenolic content (17.21–266.83 mg GAE/100 g) and antioxidant capacity (DPPH, ORAC and ABTS assays; 0.63–24.10 µg eq. Tx/g, 1.61–40.82 µg eq. Tx/g and 1.89–68.54 µg eq. Tx/g, respectively), and significantly reduced ROS production in human hepatoma cells. In addition, mixtures of honey with 10% of propolis improved the results obtained with natural honey, increasing the value of total phenolic content and antioxidant capacity. A significant positive correlation was observed between total phenolic compounds and antioxidant capacity. Therefore, the antioxidant capacity could be attributed to the phenolic compounds present in the samples, at least partially. In conclusion, our results indicated that thyme and chestnut honey supplemented with propolis can be an excellent natural source of antioxidants and could be incorporated as a potential food ingredient with biological properties of technological interest, added as a preservative. Moreover, these mixtures could be used as natural sweeteners enriched in antioxidants and other bioactive compounds.

The objective of this work was to study the phenolic profile and composition in relation to antioxidant activity of fifteen samples of commercial red, rosé and white wines originating from six native grape varieties and produced in important wine regions from Romania. The profile and quantification of major phenolic compounds were performed by direct injection of wines in the LC-MS system, using DAD and ESI (+) MS techniques, in parallel with the total phenolic content (TPC) measured by spectrometry and the free radical scavenging activity, against 2,2-diphenyl-1-picrylhydrazyl (DPPH). There were identified 38 polyphenols in wines, including 3 flavan-3-ols, 17 flavonols, 12 anthocyanins and 6 stilbenes. The red wines had significant higher phenolic content and antioxidant capacity, followed by rosé and white wines. The richest phenolic content and antioxidant activity was obtained for ‘Feteasca Neagra’ (Tohani) among red wines and for ‘Feteasca Regala’ (Jidvei) among white wines. TPC values were positively correlated with the antioxidant capacity in all white wines and only for the red ‘Feteasca Neagra’ assortment, while for the ‘Babeasca Neagra’ assortment negative correlations were obtained. From the 38 variables, flavan-3-ols have exerted the greatest influence on wine differentiation, based on their colour (red, rosé and white). The study also revealed significant differences between cultivars, both qualitative and quantitative, in terms of their polyphenolic composition, that could be important in the cultivar authentication of wines from these varieties.

Recently, plant-based milk substitutes, as an emerging industry, are receiving more attention. Despite that, these dairy alternatives have not been adequately studied for their functional properties. Thus, the current research was devoted to study the satiety potential through in vitro secretion of cholecystokinin (CCK) and glucagon-like peptide-1 (GLP-1), and the antioxidant capacity of these dairy alternatives after in vitro digestion. The enteroendocrine cell line, STC-1, was used to measure satiety hormones release (CCK and GLP-1) by enzyme-linked immunoassay (ELISA). Also, total phenolic and flavonoid contents and antioxidant capacity (using oxygen radical absorbance capacity [ORAC], ferric reducing antioxidant power [FRAP], and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid [ABTS] assays) were measured before and after in vitro digestion. The results demonstrated that CCK secretion was significantly (p<0.05) higher for cow's milk (350.64 pg ml-1 ) as compared to plant-based milk substitutes. Among the plant-based milk substitutes, tiger nut milk showed the highest CCK stimulant (228.96 pg ml-1 ), followed by hazelnut milk (220.04 pg ml-1 ). Concerning GLP-1 release, the data exhibited that spelt milk was the food with the highest induction of GLP-1 hormone secretion, followed by cow's milk (910.17 and 876.59 pg ml-1 , respectively), but without any significant differences between them. total phenolic content (TPC) values strongly increased after in vitro digestion, cow's milk and soymilk being the samples with the highest TPC values after in vitro digestion (165.76 and 153.71mg GAE/100ml, respectively). In line with TPC values, soymilk had the highest ORAC, ABTS, and FRAP values after in vitro digestion (25.41, 8.17, and 2.51µmol TE/ml, respectively). Thus, these dairy alternatives could be an adequate substitute for cow's milk, according to its satiety and antioxidant capacity. PRACTICAL APPLICATION: The first study deals with the efficacy of plant-based milk substitutes as satiating foods. Spelt milk was the highest stimulant for GLP-1 secretion. Tiger nut milk showed the highest CCK stimulant, followed by hazelnut milk. TPC and total antioxidant capacity increased after digestion.

During the production of a honey brand, artisanal or fresh honey is usually heated and filtered with the purpose of to improve fluency and this way can to facilitate its packaging process. However, an overheated honey can change the original antioxidant capacity, mainly due to the damage that the phenolic compounds have in the honeys. For this reason, the purpose of this work was to determine the behavior of the antioxidant capacity and total phenolic content in twelve samples of honey brand available in the Mexican market. 2, 2-diphenyl-1-picryhydrazyl (DPPH) free radical scavenging activity and total phenolic content were measured. Moreover, moisture, hydroxymethylfurfural (HMF) content, color parameters (L*, a* and b*) and fructose and glucose content were also determined by the purpose to support the study of antioxidant capacity in the samples of honey brand studied. The results indicated that honey brands showed an antioxidant capacity in normal levels, in comparison to other types of honey from different countries, despite the fact that the total phenolic content values were relatively low. This behavior observed may be due to the fact that the formation of the compounds with high antioxidant capacity from Maillard reactions, mainly HMF, during the heat of the honeys, which contributed in an important way with the values of the antioxidant capacity observed.

Changes in phenolic compounds and their antioxidant capacities in jujube (Ziziphus jujuba Miller) during three edible maturity stages

Colostrum is the primary source of initial acquired immunity and provides an antioxidative protection of newborn. The aim of present study was to analyze and compare the changes in total antioxidant capacity (TAC) and total phenolic contents (TPCs) colostrum’s of Honamli and Hair goat breeds on the first 5 days after parturition. The spectrophotometric ABTS method and the Folin–Ciocalteu assay were used. TAC and TPCs values were decreased gradually as the transition period advances. Both values were highest on the day first of calving as compared to rest of the days. Honamli goat colostrum samples had a higher TAC value than Hair goat and was showed significant (P less than 0.05) difference amongst the breeds. However, TPCs in Hair goat colostrum showed highly significant (P less than 0.05) difference than those of Honamli goat. In conclusion, TAC and TPC values in goat colostrum showed differences among goat breeds and exhibits daily rational changes.

The hawthorn Crataegus mexicana is a traditional Mexican fruit with properties that make this fruit useful for the treatment of many ailments, including diseases of the respiratory and urinary tract. This paper reports the antioxidant capacity of the n-hexane, dichloromethane, ethyl acetate, acetone, ethanol and methanol extracts of C. mexicana. Samples were evaluated for total phenolic and carotenoid contents, 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging, the inhibition of the formation of thiobarbituric acid reactive species (TBARS) and the neutralization of the cation-radical 2,2´-azino-bis(3ethyl benzothiazoline-6-sulfonic acid) diammonium salt (ABTS). The total phenolic content was 2.65 ± 0.23 mg of gallic acid equivalents per gram, and the carotenoid content was 26.4 ± 0.02 µg/g in dry hawthorn skin. The most active extract in scavenging DPPH radicals and inhibiting TBARS formation was the acetone extract, with activities of 21.9 ± 0.15 and 13.27 ± 0.70%, respectively, at 10 mg/L. The extracts were compared for activity against ascorbic acid, caffeic acid, α- tocopherol and quercetin. The acetone extract was the most active, with an IC50 value of 15.2 mg/L in DPPH and 17.7 mg/L in TBARS. A high correlation was observed between the results for TBARS and DPPH. These results demonstrate the potential nutritional and antioxidant value of this Mexican fruit.

Mexican oregano (Lippia graveolens Kunth) is one of the most important species worldwide due to its human health benefit properties and high economic value. Oregano leaves are primarily used for essential oil extraction, generating substantial agro-industrial waste known as bagasse (OB). It has been reported that OB still contains several bioactive compounds with high antioxidant activity. This study aimed to evaluate the extraction conditions to recover phenolic compounds and assess their antioxidant capacity in OB extracts obtained through ultrasound. A 3k Box-Behnken design was employed to explore the effects of temperature, mass/volume ratio, and [EtOH]. Total phenolic content and antioxidant capacity against DPPH· and ABTS·+ radicals were determined. The increase in temperature and m/v ratio promoted the extraction of phenolic compounds, with strong correlations to antioxidant activity by DPPH· (0.81) and ABTS·+ (0.82) assays. A quadratic effect by [EtOH] was observed, with a maximum value of 50% ethanol. The highest value of total phenolic content (35.66 mgGAE/gdm), and antioxidant capacity against DPPH· (100.94 mgTE/gdm) and ABTS (93.02 mgTE/gdm) radicals were achieved in treatment 13 (0.02 mg/mL, 50% EtOH, and 90°C). The OB is a potential source of bioactive compounds with potential applications in functional food development.

Phenolic compounds are widely present in forage. However, few studies have been carried out to investigate the presence of these compounds in animal products such as milk. In this study, the total phenolic content (TPC) and ferric reducing-antioxidant power (FRAP) of milk produced under agroecological and conventional management systems in southern Brazil were determined. Three systems were compared: (a) agroecological, with intensive rotational grazing, also known as Voisin grazing (ECO); (b) semi-intensive conventional (SIC); and (c) conventional grazing (CGR) (n = 8 per group). Pastures with distinct and more diverse botanical composition were observed on the ECO farms. Significantly (P < 0.05) lower amounts of TPC were found in agroecologically produced milk in autumn and summer and the CGR system showed the highest FRAP value (P < 0.05) for the samples collected in autumn. Positive correlations where found between the TPC and FRAP values obtained for the milk samples (0.198, P < 0.05), milk FRAP and forage TPC values (0.344, P < 0.05), and the TPC and FRAP values obtained for the forage (0.70, p < 0.01). PCA applied to the UV spectra dataset (200-350 nm) clearly distinguished the samples collected from the ECO system in the winter. Our results revealed that, under the conditions prevalent in southern Brazil, since the cows were allowed to graze in all of the systems, the TPC and antioxidant capacity of the milk samples showed minimal variation. However, since the forage TPC and FRAP values for the milk were correlated, TPC appears to be a promising variable for the purpose of monitoring forage prior to its selection aimed at enhancing the antioxidant activity of milk.

Background: Edible bean sprouts are popular fresh vegetables widely recognized for their nutritional quality. However, while their antioxidant capacity and phenolic composition in both solvent-soluble and solvent-insoluble extracts has not been systematically evaluated. Methods: The antioxidant capacity and phenolic composition in both solvent-soluble and solvent-insoluble fractions of 12 cultivars of edible bean sprouts were evaluated, and relationships of antioxidant capacity and total phenolic content were also analyzed. Results: Sprouts demonstrated a wide range of antioxidant capacity and total phenolic content, with lower but substantial antioxidant capacity and total phenolic content in the solvent-insoluble fractions. Highest levels were found in the green mung bean sprout. Phenolic compounds, such as catechin, ellagic acid, ferulic acid, gallic acid and p-coumaric acid were widely detected in these sprouts. Additionally, a positive correlation was discovered between antioxidant capacity and total phenolic content in these edible bean sprouts. Conclusions: Germination generally resulted in the accumulation of antioxidant phenolics in the most edible bean sprouts. Edible bean sprouts with high antioxidant phenolics can be valuable natural sources of dietary antioxidants for the prevention of oxidative stress-related chronic diseases. Keywords: Bean sprout, Germination, Antioxidant capacity, Radical scavenging capacity, Phenolic composition, Solvent-insoluble phenolics