Search Results (110)

Aronia juice is well-known for its high nutritional and biological value, due to its polyphenol content, which has a powerful antioxidant effect. However, the high polyphenol content of aronia juice is associated with an astringent flavor, which diminishes consumer acceptance. To improve the flavor of aronia juice, β-cyclodextrin (0–2% w/v) or gelatin (0–0.4 mg/L) were added before pasteurization. The juice samples were first examined organoleptically, and monitored for total phenolic compounds, antioxidant capacity, total flavonoids, total monomeric anthocyanins, polymeric color, pH, total soluble solids, and color. The organoleptic test demonstrated that both β-cyclodextrin and gelatin juice aroma reduced astringency and increased sweetness, whereas β-cyclodextrin also reduced juice aroma. β-cyclodextrin significantly increased polymeric color and total soluble solids (p < 0.05), whereas antioxidant activity, total flavonoids, and monomeric anthocyanins remained unchanged compared to the unpasteurized control. In contrast, the addition of gelatin dramatically reduced total phenolic compounds, antioxidant capacity, and total flavonoids, while enhancing polymeric color and maintaining monomeric anthocyanins with minor decreases relative to pre-pasteurization levels (p < 0.05). A consumer study was conducted with control juice and juices with 2% w/v β-cyclodextrin or 0.4 mg/L gelatin added. The results confirmed the change in flavor profile by masking or removing astringency and astringent aftertaste, as well as increasing sweetness, which significantly improved overall acceptability (p < 0.05). Full article

Corn is one of the most consumed cereals in the Mexican diet. In this country, there are multiple varieties that exhibit nutraceutical potential due to their content of different metabolites with biological activity, such as blue corn. Another variety that has received little study is the red pigmented corn variety Chilac from Puebla, Mexico, which is being studied for its nutraceutical potential. A differential extraction using the Soxhlet method was carried out to evaluate the phenolic content, total flavonoid content, and monomeric anthocyanins, and free radical scavenging test was performed using the DPPH reagent. A proximate analysis was also conducted to identify the main macronutrients. The results of the proximate analysis were comparable to those of other traditional corn varieties, with carbohydrates being the macronutrient present in the highest amount at 77.9%. Regarding phenolic content and the presence of anthocyanins, the best extractions were obtained using alcoholic solvents; for example, ethanol for phenols, yielding 1368.420 ± 104.094 mg of gallic acid equivalents (GAE)/kg plant. In contrast, the flavonoid content was higher in the aqueous extract, with 833.984 ± 65.218 mg QE/Kg. In the case of the DPPH assay, the best result was obtained with ethyl acetate (73.81 ± 5.31%). These findings provide a foundation for expanding the use of corn varieties with nutraceutical potential, opening the possibility of studies focused on deeper characterization. Full article

Sweet potato is a valuable root due to its nutritional benefits, health-promoting properties, and technological applications. The peel, often discarded during food processing, can be employed in the food industry, supporting a circular economy. Purple sweet potato peel (PSPP) is rich in anthocyanins, which can be used as natural colourants and antioxidants. Optimising their extraction can enhance yield and reduce costs. The current work aimed to optimize anthocyanin and antioxidant recovery from PSPP using a Box-Behnken design and sonotrode ultrasound-assisted extraction (sonotrode-UAE). Three independent variables were analysed: extraction time (2–6 min), ethanol concentration (35–85%), and liquid-to-solid ratio (10–30 mL/g). The dependent variables included total monomeric anthocyanin content (TMAC), individual anthocyanins, and antioxidant activity. TMAC in 15 extracts ranged from 0.16 to 2.66 mg/g PSPP. Peonidin-3-caffeoyl-p-hydroxybenzoyl sophoroside-5-glucoside was the predominant anthocyanin. Among four antioxidant assays, Ferric-reducing antioxidant power (FRAP) showed the highest value. Ethanol concentration significantly influenced anthocyanin and antioxidant recovery (p < 0.05). The model demonstrated adequacy based on the coefficient of determination and variation. Optimal extraction conditions were 6 min with 60% ethanol at a 30 mL/g ratio. Predicted values were validated experimentally (coefficient of variation <10%). In conclusion, PSPP is a promising matrix for obtaining anthocyanin-rich extracts with antioxidant activity, offering potential applications in the food industry. Full article

Infertility is a significant global health concern, and incorporating antioxidants into sperm preparation media is one strategy to enhance sperm quality and decrease infertility rates. This study aimed to investigate the phytochemical compounds of red cotton stamen extracts and their effects as antioxidants in improving the quality of bull frozen semen. Among the extracts, RCU contained the highest levels of total phenolics, total tannins, and total monomeric anthocyanins along with the strongest ABTS free radical scavenging activity and protein denaturation inhibition. Exposing sperm to FeSO₄-induced oxidative stress resulted in significantly reduced motility, viability, and normal morphology. However, treatment with RCD, RCU, and RCM improved these parameters. Additionally, the FeSO₄-induced group showed elevated levels of reactive oxygen species (ROS) and advanced glycation end products (AGEs) compared to the normal control, whereas all red cotton stamen extracts effectively reduced these levels. In conclusion, red cotton stamen extracts, rich in phenolic bioactive compounds, demonstrated strong free radical scavenging capacity and improved sperm motility, viability, and morphology by neutralizing free radicals and enhancing antioxidant defenses. These findings suggest that the red cotton stamen extracts, particularly RCD and RCU, offer benefits for sperm preservation. Full article

Public concerns about the health risks of synthetic antioxidants have prompted the meat industry to look for natural alternatives rich in phenols with strong antioxidant properties. This study investigates the use of blackcurrant (BCP), lingonberry (LP), and sour cherry (SCP) powders as natural substitutes for synthetic nitrites in reformulating two clean-label salami types, smoked and cooked and smoked and scalded, with a focus on their effects on oxidative stability during processing and refrigerated storage (4 °C). Nitrite-free formulations were prepared with each fruit powder at three inclusion levels to provide total phenolic contents of 90, 200, and 300 mg gallic acid equivalents (GAE)/kg of processed meat. A nitrite-containing control (90 mg/kg) and an additive-free control were included for comparison. The phytochemical profiles of powders were characterized by total phenolic, flavonoid, monomeric anthocyanin contents, and L-ascorbic acid levels. Antioxidant activity was assessed via 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and ferric reducing antioxidant power (FRAP) assays. Salami samples were analyzed for proximate composition, and lipid oxidation was monitored at 0, 15, and 30 days of storage using peroxide value, inhibition of oxidation, p-anisidine value, TOTOX, and thiobarbituric acid value. Fruit powders demonstrated dose- and type-dependent inhibition of primary and secondary lipid oxidation, enhancing oxidative stability during processing and storage. After 30 days of storage, oxidation markers in fruit-enriched salami remained below recommended thresholds, confirming effective control of lipid oxidation. The inhibitory potential followed the order BCP > LP > SCP, consistent with antioxidant profiles as reflected by DPPH and FRAP values. BCP at 300 mg GAE/kg showed a stronger lipid oxidation inhibition than sodium nitrite. Promising improvements in lipid oxidation resistance were also observed with LP at 300 mg GAE/kg and BCP at 200 mg GAE/kg. These findings highlight the potential of fruit-derived antioxidants to support the development of more sustainable, value-added meat products without compromising quality. Full article

Grapes are rich in bioactive compounds, including phenolics and anthocyanins, which exhibit antioxidant properties and offer potential health benefits. The accumulation of these compounds is influenced by agronomic practices, particularly rootstock selection and training systems. This study evaluated the effects of different rootstocks (‘IAC 766 Campinas’ and ‘106-8 Mgt’) and training systems (low and high vertical shoot positioning) on the polyphenolic composition and antioxidant activity in the skins and pulps of Vitis labrusca and Brazilian hybrid grapes. The analyses included total phenolics, total flavonoids, monomeric anthocyanins, and antioxidant activity (DPPH and FRAP assays), as well as the individual polyphenolic profile in grape skins. The results indicated that both rootstock and training system significantly affected the accumulation of bioactive compounds and antioxidant capacity. Grapes trained on high trellises exhibited higher concentrations of bioactive compounds, while those from low trellises showed an enhanced phenolic composition. Among Vitis labrusca varieties, ‘Bordô’ had the highest bioactive compounds, while ‘Isabel’ stood out for specific phenolic acids. In hybrid cultivars, the ‘106-8 Mgt’ rootstock boosted antioxidant compounds, while ‘IAC 766 Campinas’ enhanced flavonoid, anthocyanin, and phenolic acid levels. Malvidin-3-O-glucoside emerged as the predominant anthocyanin. These findings underscore the importance of optimizing rootstock selection and training systems to enhance the phenolic composition and antioxidant potential of grapes. Full article

In this study, the reactivity of procyanidins and anthocyanins in young and aged Prokupac wines toward salivary proteins is investigated via SDS-PAGE and UHPLC-QTOF-MS to determine the differences between the phenolic compounds of red wine in relation to the aging process of wine. SDS-PAGE analysis revealed that procyanidins, flavanol-anthocyanin polymers, and ellagitannins in aged wine have strong affinities for salivary proteins, leading to the formation of insoluble complexes. By contrast, young wine contained predominantly procyanidins with high salivary protein affinity, as well as monomeric flavan-3-ols and anthocyanins, which mainly form soluble aggregates, while polymeric phenolics were less represented. Electrophoretic patterns further showed that seed-derived procyanidins mainly formed insoluble complexes with salivary proteins, whereas skin-derived anthocyanins tended to form soluble ones. The total content of all phenolic compounds quantified by UHPLC-QTOF-MS was 2.5 times higher in young wine than in aged wine, primarily due to the significantly greater abundance of malvidine-3-O-glucoside in young wine (eightfold higher level in young wine). Targeted UHPLC-QTOF-MS analysis of selected phenolics confirmed the electrophoretic results and showed a higher binding affinity of procyanidins in aged wine compared to young wine, as well as a higher percentage of procyanidin binding compared to anthocyanins, independent of the age of the wine. Sensory evaluation showed that aged wine had higher tannin quality scores, whereas young wine exhibited greater acidity and astringency, with bitterness being comparable between them. These results highlight the influence of wine aging on the interaction between phenolic compounds and salivary proteins and emphasize the dominant role of procyanidins in protein binding and the potential synergistic contribution of anthocyanins to mouthfeel perception. Full article

Impatiens L. plants are sources of polyphenols with antioxidant and antimicrobial activities. There are scarce data about these effects in the case of Impatiens hawkeri W. Bull, a relevant species in ornamental plant industry with ethnobotanical backgrounds. The aim of this study is to provide information regarding the antioxidant and the antibacterial properties of the ethanol extracts of I. hawkeri to support new applications. HPTLC was used to estimate the concentration of seven known bioactive metabolites reported among Impatiens plants. Total phenolics, flavonoids, and monomeric anthocyanins were also measured. An orthogonal platform with chemical and biological in vitro assays was used to evaluate the antioxidant activity of the extracts. Antibacterial activity was determined by broth microdilution assay on human pathogenic bacteria. The results were integrated by correlation and principal component analysis to identify the most promissory plant part and drying technique to optimize the evaluated activities. Data suggest the tentative identification of bioactive chemical markers for the antioxidant and antibacterial activities of the extracts (quercetin and rutin). Freeze-dried leaves and flowers are the most promissory parts of I. hawkeri for the development of antioxidant nutraceuticals or preservatives. The results demonstrate that phenolic compounds play a major role in the antioxidant and antibacterial activities of I. hawkery extracts. Full article

The ‘BRS Vitoria’ grape has sensory characteristics that favor its consumption. However, different rootstocks and harvest periods can directly influence its phenolic composition, physicochemical and morphological characteristics, and mineral content. This study evaluates the mineral and anthocyanin composition of the ‘BRS Vitoria’ grape from a production cycle (PC1: ‘IAC 572’ rootstock, main harvest) and compares its physicochemical, morphological, and mineral characteristics to other cycles (PC2: ‘Paulsen 1103’ rootstock, second harvest; PC3: ‘IAC 572’ rootstock, second harvest; and PC4: ‘Paulsen 1103’ rootstock, main harvest), highlighting its potential for use and providing initial insights into the influence of rootstocks and environmental conditions. PC1 grapes contained important amounts of potassium, phosphorus, calcium, magnesium, iron, manganese, and zinc (345.16, 50.50, 20.34, 13.61, 0.54, 0.27, and 0.03 mg⋅100 g⁻¹, respectively), and a complex anthocyanin profile, predominantly derived from malvidin, which supports their use in processing due to the thermal stability. In the second part of the study, PC2 grapes stood out for their skin percentage and acidity. PC3 grapes exhibited higher values in parameters associated with size, mass, and mineral content, which may have been influenced by the use of the ‘IAC 572’ rootstock. PC4 grapes showed the highest maturation index (38.68), total phenolic compounds (1750.88 mg EGA⋅kg⁻¹), and total monomeric anthocyanins (742.86 mg mv-3,5-glc⋅kg⁻¹). These results may have been influenced by the environmental conditions during the main harvest season. Bunches from all cycles were cylindrical, very compact, with dark red-violet berries and featuring thick skin with pruine and firm colorless, seedless flesh. The study of the influence of these factors is complex due to the impact of various other variables and the synergistic effect between them. Despite physicochemical and morphological differences, ‘BRS Vitoria’ grapes from different PCs are suitable for fresh consumption and processing, potentially as a nutraceutical ingredient. Full article

Paulownia leaves and flowers have been used to prepare medicinal tea in traditional Chinese medicine; however, there has been no scientific validation of bioactive compounds so far. A systematic study is presented to establish a suitable drying protocol for leaf and flower tissues that may be useful in preserving bioactive compounds and retaining high antioxidant capacity. Additionally, a suitable drying protocol is commercially imperative for improving the shelf life of these tissues. In this study, P. elongata and P. fortunei juvenile leaves and flowers at two stages (pre- and post-anthesis stages) were subjected to five drying treatments to study the drying characteristics and were analyzed for total polyphenols, total flavonoids, and antioxidant capacity. Oven drying, sun drying, shade drying, freeze drying, and microwave drying were the five drying methods that were used to evaluate their efficacy on the drying characteristics and antioxidant potential. Fresh and dried tissues were analyzed for total polyphenols, total flavonoids, total tannins, total catechins, total monomeric anthocyanins, and total antioxidant capacity. A strong correlation was observed between the moisture content and total polyphenols (the lower the moisture content, the lower the polyphenols). Sun drying was the best method for Paulownia tissues based on color retention, moisture content, overall cost effectiveness, time, and antioxidant capacity. Shade drying was the second-best method based on the same parameters. No significant differences were observed between P. elongata and P. fortunei tissues in their total antioxidant capacity. Leaves and flowers at the pre-anthesis stage (stage 6) registered a higher level of total polyphenols, flavonoids, tannins, catechins, and resultant antioxidant capacity in comparison with flowers at stage 9 (the post-anthesis stage). Monomeric anthocyanins were highest in P. elongata flowers at stage 6. A strong correlation was observed between moisture content and the antioxidant levels of Paulownia tissues. Full article

As widely generated by-products with significant bioactive compound content, sugarcane molasses exhibits high potential for valorization. For the purpose of bioactive compound extraction from sugarcane molasses, ultrasound-assisted extraction with various hydroethanolic solvents (0, 2.5, 5, 7.5, and 10% ethanol) at different pH values (4.11, 5.11, 6.11, and 7.11) was examined. In the obtained sugarcane molasses extracts, the content of total phenolics, monomeric anthocyanins, total flavonoids, total tannins, and antioxidant capacity (DPPH) was estimated alongside the determination of molasses’ major components through GC-MS analysis Based on the GC-MS analysis of molasses, sugars and nitrogenous compounds emerged as the most abundant compounds classes. Hydroethanolic solvent of 2.5% at pH 6.11 exhibited the most prominent extraction power regarding total phenolics (22074.98 µg GAE mL⁻¹) and total flavonoids (245.42 µg QE mL⁻¹). Furthermore, extraction with 2.5% hydroethanolic solvent at pH 5.11 displayed the highest total tannins (1177.85 µg CE mL⁻¹). The behavior of monomeric anthocyanins in ultrasound-assisted extraction with hydroethanolic solvent was slightly different, where 2.5% hydroethanolic solvent extracted the highest amount at pH 4.11 (11.1 µg CGE mL⁻¹) and 7.11 (10.68 µg CGE mL⁻¹). The results of the DPPH assay indicated that extracts obtained using 2.5% hydroethanolic solvent at pH 4.11 (68.35%) and pH 5.11 (68.10%) evinced the highest neutralization power against DPPH free radicals. In conclusion, 2.5% ultrasound-assisted hydroethanolic solvent and pH 4.11-6.11 were the most suitable for extracting bioactive compounds from sugarcane molasses. Full article

The increase in the incidence of hyperglycemia and diabetes poses the challenge of finding cost-effective natural inhibitors of starch digestion enzymes. Among natural compounds, phenolics have been considered as promising candidates. The aims of this study were as follows: (a) to investigate the effectiveness of the inhibition of different winemaking byproducts towards intestinal brush border α-glucosidase and pancreatic α-amylase in vitro; (b) to calculate an efficacy index relative to the standard acarbose for the phenolic pool of winemaking byproducts, as well as for isolated phenolic compounds and for the phenolic pools of different plants studied in the literature, in order to rank winemaking byproducts with respect to the reference drug and other natural alternatives. Among winemaking byproducts, red grape skins showed the highest inhibitory activities towards both α-glucosidase and α-amylase, which were, on average, 4.9 and 2.6 µg acarbose equivalents/µg total phenolics (µg Ac eq/µg GAE), respectively. A correlation was observed between the total phenolic contents of red grape skins and their inhibitory effectiveness, which is useful for standardizing the efficacy of phenolic extracts obtained from different winemaking processes. In general, the inhibitory activity of the phenolic pool of grape skins was higher than those of isolated phenolic compounds, namely anthocyanins and monomeric and polymeric flavanols and flavonols, probably due to synergistic effects among compounds. Hence, bioactive phenolic fractions could be produced with the focus on functionality rather than purity, in line with the principles of sustainable processing. Based on the efficacy index developed to compare different phenolic compounds and phenolic-rich plants studied in the literature as starch digestion enzyme inhibitors, red grape skins proved to be cost-effective candidates. Full article

An emerging drying method, far-infrared radiation heating-assisted pulsed vacuum drying (FIR-PVD), was employed to dry raspberries. In this study, the impacts of FIR-PVD, freeze drying (FD), and hot air drying (HAD) on drying characteristics and quality attributes, including color, rehydration ratio, content of total phenolics (TP), content of total monomeric anthocyanins (TMA), antioxidant activity, and microstructural attributes of dried raspberries, were examined. Results indicated that FIR-PVD notably shortened the drying time by 47.78% compared to HAD and by 73.89% compared to FD. The FIR-PVD samples exhibited the highest TP content, DPPH radical scavenging activity, and FRAP value, which were 17.73%, 6.09%, and 38.16% higher than those of the FD samples, respectively, and 2.78%, 2.77%, and 18.74% higher than those of the HAD samples. Significant correlations (p < 0.05) were observed between antioxidant capacity, as measured by DPPH and FRAP assays, and TP content. However, FD at a low temperature led to a higher TMA content than FIR-PVD and HAD. FIR-PVD resulted in the highest ΔE values of dried products due to the lightness enhancement. In addition, the dried products obtained by FIR-PVD had better rehydration capacity. These findings indicate that FIR-PVD presents a promising alternative method for drying raspberries, as it enhances drying efficiency and improves the quality attributes of the dried products. Full article

One of the food industry’s greatest challenges is to find natural ingredients capable of conferring antioxidant and color properties. In addition, the agri-food industry generates by-products that are often treated as waste, despite their abundance of phytochemicals that can be recovered and used as food ingredients. This study explores the potential of elderberry pomace, an industrial by-product of juice processing rich in anthocyanins and polyphenols, as a natural food additive in blueberry sorbet. Elderberry pomace was incorporated into the sorbet formulation in powder form or as aqueous extracts at two different concentrations. The analysis of the pomace extract by UHPLC-DAD-MS showed the presence of four anthocyanins: cyanidin-3,5-O-diglucoside, cyanidin-3-O-sambubioside-5-O-glucoside, cyanidin-3-O-sambubioside, and cyanidin-3-O-glucoside. The physicochemical properties of the sorbets such as pH, °Brix, overrun, melting rate, and color were evaluated, as well as their levels of total phenolic compounds, total monomeric anthocyanins, and in vitro antioxidant activity. The potential of sorbets to stimulate the growth of probiotic bacteria was evaluated and a sensory analysis was conducted to assess consumer acceptance. Results indicated that the sorbet containing the more concentrated extract presented higher overrun, faster melting rate, higher contents of phenolic compounds and anthocyanins, and higher antioxidant activity compared to the control. Additionally, this formulation showed a darker hue (lower L* value) and a tendency to stimulate probiotic bacteria. Moreover, the sorbets with pomace in their composition had good consumer acceptability. These findings highlight the potential of elderberry pomace to be used as a natural, sustainable ingredient in the ice cream industry, aligning with growing consumer trends towards healthier and eco-friendly products. Full article

There is increasing interest in Australian finger lime (Citrus australasica) due to its nutritional and bioactive potential. In this study, polar extracts from five finger lime cultivars were investigated for their potential bioactivity using a range of assays: antioxidant capacity (total phenolic content (TPC), ferric reducing antioxidant power (FRAP), and cupric reducing antioxidant capacity (CUPRAC)), total monomeric anthocyanin content (TMAC), anti-diabetic activity (α-glucosidase and α-amylase inhibition), anti-Alzheimer activity (acetylcholinesterase inhibition), Skin-whitening activity skin-brightening activity (tyrosinase inhibition), and anti-inflammatory activity (COX-2 inhibition). Commercial Tahitian lime was used as a “control” (comparison). The TPC ranged from 328 to 779 mg GAE/100 g dry weight (DW) in the pulp (compared to 1043 mg GAE/100 g for Tahitian lime) and from 755 to 1048 mg GAE/100 g in the peel (1704 mg GAE/100 g for Tahitian lime). A similar range of variation was seen for FRAP, ranging from 114 to 436 mg TE/100 g DW in the pulp (422 mg TE/100 g for Tahitian lime) and 259 to 495 mg TE/100 g DW in the peel (491 mg TE/100 g for Tahitian lime). Similarly, the TFC was generally lower in finger lime pulp (100–392 mg QE/100 g DW) compared to Tahitian lime (312 mg QE/100 g). The polar extracts did not show any significant inhibition of α-glucosidase, α-amylase, tyrosinase, or COX-2. One finger lime variety showed moderate (>50%) inhibition of acetylcholinesterase (AChE) at the highest concentration screened (~1500 mg/L), as did Tahitian lime. Additionally, in silico docking against acetylcholinesterase suggested that some of the polyphenols present, including catechin, quercetin-3-glucoside, and cyanidin-3-glucoside, could potentially dock to AChE and inhibit it. This is the first time the species has been investigated for many of these bioactive properties, and also the first time in silico docking has been performed to explore which potential compounds from this species could provide its bioactivity. Although little bioactivity was generally found across the applied bioassays, these findings nevertheless provide important basic data for future research and any claims about the potential health benefits of Australian finger lime. Full article