Antioxidant Phenolic Compounds Research Articles

Ethyl gallate ameliorates diabetes-induced Alzheimer's disease-like phenotype in rats via activation of α7 nicotinic receptors and mitigation of oxidative stress

Cognitive decline, an important comorbidity of type 2 diabetes (T2D), is attributed to oxidative stress and impaired cholinergic signaling in the brain. The α7 nicotinic acetylcholine receptor (α7nAChR) is densely distributed in the hippocampus and cortex, and exerts neuroprotective and procognitive actions. Ethyl gallate (EG), a natural phenolic antioxidant compound, showed high in-silico binding affinity towards α7nAChR and brain penetrability. Therefore, the present study aimed to evaluate the involvement of α7nAChR in the potential of EG to ameliorate T2D-induced Alzheimer's disease-like condition. T2D was induced by intraperitoneal (i.p.) injection of streptozotocin (35 mg/kg) in rats on high-fat diet. Diabetic animals were treated with EG (10 and 20 mg/kg, i.p.) for four weeks, and their learning and memory performance was evaluated by the Morris water maze (MWM). Further, the brains were subjected to biochemical analysis of antioxidants like glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT), and oxidative stress marker malonaldehyde (MDA). While diabetic rats showed a significant decline in cognitive performance in the MWM, a substantial improvement was noticed following EG treatment. Further, the diabetes-associated reductions in GSH, SOD, and CAT levels, along with increased MDA contents in the brain, were effectively restored by EG. Interestingly, pre-treatment with α7nAChR antagonist methyllycaconitine (1 mg/kg, i.p.) attenuated the effects of EG on behavioral and biochemical parameters. The results suggest that EG may augment cholinergic signaling in the brain via α7nAChR to mitigate oxidative stress, consequently alleviating T2D-associated dementia. Therefore, EG could be a potential candidate for addressing cognitive impairment comorbid with T2D.

Optimization of the ultrasound-assisted extraction of phenolic antioxidants from Cistus salvifoliusL. using response surface methodology.

The current work aims to optimize the ultrasound-assisted extraction (UAE) of Cistus salviifolius L. (aerial parts) antioxidative phenolic compounds using response surface methodology. A Box-Behnken design has been conducted to investigate the effect of four factors, namely: (i) percentage of ethanol (50-90%, v/v), (ii) temperature (40-80°C), (iii) solvent-solid ratio (10-50 mL g-1) and (iv) extraction time (5-25min) on four responses, namely: total phenolic content (TPC), total flavonoid content (TFC) 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical inhibition, and ferric reducing antioxidant power (FRAP). Based on the desirability index, UAE with 50% (v/v) ethanol, at 80 oC, using a solvent-solid ratio of 32.24 mL g-1, for 21 min resulted in the maximum recovery of phenolic antioxidants. Under optimum conditions, the experimental values of TPC, TFC, % DPPH scavenging activity, and FRAP were 171.67 ± 4.69 mg GAE g-1, 26.87 ± 0.78 mg CE g-1, 81.31 ± 0.16%, and 1038.22 ± 7.69 μmol TE g-1, respectively. Results highlight that the developed eco-friendly method is appropriate for the improved recovery of phenolic antioxidants from C. salviifolius L.

Comprehensive Study of Sustainable Pressurized Liquid Extractions to Obtain Bioavailable Antioxidant Phenolic Compounds from Grape Seed By-Products

Few investigations have been conducted to evaluate pressurized liquid extraction (PLE) technology as a sustainable method for the recovery of phenolic compounds of grape seed by-products. In this study, PLE combined with an experimental design was evaluated for optimizing the sustainable extraction of phenolic compounds from grape seed by-products. The solvent ethanol content (X1, 0–100%), temperature (X2, 20–100 °C) and time (X3, 1–11 min) were studied as independent experimental factors. Yield, TPC, antioxidant activity and phenolic composition were analyzed as optimized dependent variables. Two optimal extraction conditions at different temperatures (20 °C and 100 °C) were found, but thermal degradations at 100 °C allowed for selecting the optimal condition as 75% ethanol, 11 min and 20 °C. The optimal extracts showed high phenolic content (TPC = 350.80 ± 3.97 mg GAE/g extract) and antioxidant activity (ABTS, 9.31 ± 0.33 mmol Trolox/g extract), mainly composed of polymeric and mono-oligomeric flavan-3-ols. The digestion process reduced the TPC and antioxidant activity due to the low bioaccessibility of the flavan-3-ols, mainly as catechin, epicatechin and polymeric proanthocyanidin losses during the digestion process. However, increases in the antioxidant activity of the basolateral side (DDPH, 0.061 ± 0.000 mmol Trolox/g extract) were determined after in vitro transepithelial transport, which is a consequence of bioavailable catechin and epicatechin and reduced amounts of dimer B2, dimer B1, epicatechin gallate and gallic acid. Consequently, PLE combined with hydroalcoholic solvents at a low temperature resulted in a valuable methodology to obtain sustainable extracts from grape seed by-products (contributing to the circular economy), containing bioavailable phenolic compounds, which are able to increase the antioxidant status.

Utilization of Hibiscus, Tamarind and Carob in Production of Low Calories Healthy Soft Drinks

The demand for carbonated beverages is increasing, offering opportunities to develop drinks with significant health benefits. Beverages containing carob, tamarind and hibiscus offer multiple nutritional and functional benefits and can serve as healthy alternatives to other soft drinks on the market. This is particularly important given the high sugar and calorie content of traditional soft drinks, which has been linked to increased issues associated with obesity, type 2 diabetes, osteoporosis and cardiovascular disease globally. The focus of the current work is to evaluate low-calorie soft drinks made from hibiscus, tamarind and carob and sweetened with erythritol that cater to diverse consumer segments, including diabetics and health-conscious individuals. Hibiscus, tamarind and carob extracts were sweetened with 0.5, 1 and 1.5 g erythritol sugar/200 ml carbonated beverage. The results showed that the alcoholic extract from hibiscus cups gave the highest content of phenols and flavonoids (70.3 mg gallic/g on DW and 7.8 mg catechin/g on DW), followed by carob pod alcoholic extract (19.3 mg gallic/g on DW) and tamarind alcoholic extract (11.6 mg gallic/g on DW). Tamarind gave a higher content of flavonoids (2.3 mg/g) than carob (1.2 mg/g); however, carob pods had the highest antioxidant activity (91.92%), followed by tamarind pulp (87.66%) and hibiscus cups (79.76%). The soft drinks of hibiscus and tamarind sweetened with erythritol at 1.5 g/200 ml gave the best sensory properties compared with control (adjusted by sucrose at 12% brix) and others concentrations used of erythritol sugar at (0.5 and 1.5 g /200 ml carbonated beverage). Carob pods soft drink sweetened with 0.5 g erythritol /200 ml gave the best sensory characteristics compared to the control sample and others concentrations of erythritol sugar at (1 and 1.5 g /200 ml carbonated beverage), which may be due to the high content of sugars in carob. Hibiscus carbonated beverage outperformed tamarind in terms of overall acceptability and carob carbonated beverage was the least acceptable in terms of sensory properties. Carob carbonated beverage recorded the highest antioxidant activity (90.9%) and phenolic content while representing the second highest in terms of flavonoids. Tamarind carbonated beverage ranked second in terms of antioxidant activity (86.0%) and phenolic content although it ranked first in terms of flavonoids. Hibiscus carbonated beverage recorded the lowest content in terms of antioxidant activity (79.36%), phenolic compounds and flavonoids. Hibiscus, tamarind and carob are a great choice for the production of carbonated beverages because they give the beverage desirable nutritional, cosmetic and medicinal qualities. Moreover, the simplicity of production and availability of raw materials allows for the stimulation of the economy by reducing dependence on multinational companies offering unhealthy or industrialized soft drinks.

New Green Biorefinery Strategies to Valorize Bioactive Fractions from Palmaria palmata.

A biorefinery process was developed to isolate phycobiliproteins, sulfated polysaccharides, and phenolic compounds from Palmaria palmata. The extraction process was carried out in three stages using ultrasound-assisted extraction (UAE) and pressurized liquid extraction (PLE) integrated with different natural deep eutectic solvents (NaDESs). In general, PLE provided higher phycobiliprotein contents than UAE in the first step of the process. In fact, the hydrolysis product of the PLE-NaDES extracts achieved a higher antioxidant capacity than that of the UAE-NaDES extracts. Particularly, glycerol:glucose (2:1) with 50% water in combination with PLE was the most suitable NaDES to recover the highest phycobiliprotein, protein, and sulfated polysaccharide contents from Palmaria palmata in the first and second steps of the biorefinery process. Finally, a PLE-NaDES using choline chloride:glycerol (1:2) with 60% water as the NaDES was employed for the recovery of antioxidant and neuroprotective phenolic compounds from the residue of the second step, obtaining a higher total phenolic content than employing PLE with ethanol/water (70:30, v/v) as the extraction solvent. Moreover, a forced stability study revealed that the NaDESs provided a protective effect compared to the water extracts against the degradation of phycobiliproteins, preserving their color over time. This study contributes to the recovery of high-value components from an undervalued biomarine source through a sustainable biorefinery process.

Comprehensive analysis of biochemical compounds, chemical elements and metabolites modifications in maize plants infected with maize rayado fino virus (MRFV)

Maize cultivation is crucial worldwide, especially in Latin America. However, diseases related to corn stunt complex have significantly impacted crops, reducing grain productivity and quality. Maize rayado fino virus (MRFV) is part of this complex, and its symptom is characterized by chlorotic dots along veins and, depending on maize genotype, there will be stunting and an impact on the corn cob development, which can lead to productivity losses. However, this intricate plant-pathogen relationship is yet not well understood. Here, we investigated the effects of MRFV transmitted by the corn leafhopper Dalbulus maidis in infected plants in their early stage of development. To show the impact of the viral infection in the maize plant, we performed biochemical and chemical analysis and nuclear magnetic resonance (NMR). The total set of analyses showed that changes in chemical and biochemical compounds, as well as in metabolites composition and activities, can be perceived in MRFV-infected maize plants when compared to healthy plants. An increase in the activity of superoxide dismutase, catalase, peroxidase, and β-glucanase was detected, whereas small changes have been identified in antioxidant activity and phenolic compounds. For chemical components, unique changes were observed, mainly the increase in the presence of some elements such as calcium (Ca), phosphorus (P), sodium (Na), and iron (Fe). We identified 20 metabolites of the amino acids, organic compounds, and carbohydrates classes in maize plants which are regulated during MRFV infection. Maize plants reacted to D. maidis herbivory by modulating both enzymatic and non-enzymatic activities, as well as chemical compounds. This research offers insights into the responses of maize against MRFV and sheds light on parameters to be used on the search of rayado fino viral disease resistance for a sustainable production.

Polyphenols as the Main Compounds Influencing the Antioxidant Effect of Honey-A Review.

Honey is one of the most valuable components of the human diet. It is considered to be a functional food with health-promoting properties. Honey has bactericidal and bacteriostatic effects; is used to treat wounds and ulcers; relieves stress; supports the treatment of diseases of the digestive and respiratory systems; improves kidney function; and aids in convalescence. The healing and prophylactic effects of honey are closely related to its chemical composition. According to the literature, honey contains over 300 substances belonging to various groups of chemical compounds, some with antioxidant activity, including vitamins and phenolic compounds, mainly flavonoids and phenolic acids. This article provides insight into honey's chemical composition and its pro-health activities. The antioxidant properties of honey were prioritized.

Metabolic profile of fatty acids, phenolic compounds, and methylxanthines of cocoa kernels (Theobroma cacao L.) from different cultivars produced in cabruca and full sun farming systems

The demand for high-quality cocoa beans has increased in line with the growing global demand for chocolate. The chemical composition of cocoa beans can vary according to their origin and growing conditions. In this context, this study evaluated the influence of the cultivar type (CCN51 and PS1319) and the cocoa management system (cabruca and full sun) on the chemical composition of unfermented cocoa kernels. The cultivation system influenced the fatty acid composition of cocoa kernels, with higher values of linoleic acid associated with the full sun system, although higher total lipid contents were obtained in the cabruca system. The cultivar influenced the content of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), total unsaturated fatty acids (UFA) and the saturated/unsaturated ratio (S/U). Lower levels of total phenolic compounds, total anthocyanins and antioxidant properties were found in the full sun system, especially in the PS1319 cultivar. Higher levels of epicatechin and catechin were found in the cocoa kernel of the CCN51 cultivar. Theobromine and caffeine were not influenced by the treatments. Neither the PCA of total lipids and fatty acids, nor the PCA of antioxidant properties, phenolic compounds and methylxanthines indicated an isolated clustering between cultivar and cultivation system. The results showed that the factors under study influenced the chemical composition of the unfermented cocoa kernel. Furthermore, they indicated that the migration from traditional systems, such as cabruca, to full sun systems can reduce the total lipids and phenolic compounds content of the cocoa beans. When planning new plantations, the choice of genetic material should also be carefully considered to produce higher-quality cocoa butter and beans with a higher phenolic compound content.

Chia gum-gelatin-based encapsulation of chia sprouts phenolic compounds enhanced storage stability, bioavailability, antioxidant, antidiabetic, and antibacterial properties

Chia seeds are currently gaining popularity as functional and healthy foods. The developed chia 7-day sprout phenolic extract (CSP) is an abundant supply of highly concentrated antioxidant phenolic compounds with health-promoting and antibacterial properties. The easy destruction against different environmental changes and low bioavailability of these phenolic compounds are the main limitations of their applications/utilization. This study aims to microencapsulate the phenolic compounds of developed CSP for use as valuable functional food additives. Three microcapsules were prepared using coating materials, chia gum (CG), gelatin (G), and their mixture (CG/G) via the freeze-drying technique. The prepared CG-, CG/G-, and G-microcapsules demonstrated high encapsulation efficiency percentages of 97.0, 98.1, and 94.5%, respectively. They retained most of the CSP-phenolics (91.4–97.2%) and increased total antioxidant activity (108–127.1%). The prepared microcapsules released more CSP-phenolic compounds into the simulated intestinal stage (70–82%) than the gastric stage (15–24%), demonstrating that the coating materials enhance protection during the gastric stage. The produced microcapsules exhibited higher storage stability at 40 °C for 60 days than the non-capsulated CSP, indicating that the encapsulation provided enhanced stability. The prepared microcapsules microstructures showed uniform, smoother surfaces, and hidden micropores compared to their coating material microstructures. In addition, the connection between the functional groups of coating materials and CSP-phenolic compounds was demonstrated by FTIR analysis. The prepared CG-, CG/G-, and G-microcapsules can perfectly inhibit the α-amylase and α-glucosidase activities by 65, 68, 60 and 74, 78, and 70%, respectively, compared to CSP (54, and 66%). The three prepared microcapsules displayed better antibacterial with low MBC values (0.36–0.68 mg ml−1) compared to CSP (0.53–0.74 mg ml−1). The prepared CSP microcapsules can be incorporated into various food products to enhance their antioxidant, antidiabetic, and antibacterial properties.

Enhancing eco-friendly coatings: Aqueous olive leaves extract fortifies macroalgae-based packaging materials

This study incorporated bioactive compounds extracted from olive leaves (Olea europaea L.) into biodegradable films designed for preserving perishable food items like fruits and vegetables. Olive leaves, sourced from Lesvos island in Greece, yielded three aqueous extracts - OL1, OL2, and OL3 – representing different cultivated species. The antioxidant potential and phenolic compound profile of these extracts were analyzed. Subsequently, these extracts were integrated into 2% sodium alginate solutions, and the resulting mixtures were cast into 90 mm Petri dishes to form solid biofilms. Our findings reveal that the olive leaf extracts offer protection against UV–VIS radiation. Particularly, OL1 showcased the highest antioxidant capacity among the extracts examined. For the solid biofilms, various physical characteristics such as weight, diameter, density, and thickness were measured, alongside evaluating humidity, solubility in water, and water vapor permeability. The rheological properties of these solutions, influenced by temperature and extract addition, affect the viscosity, flow behavior, and gelation capacity, crucial for coating applications. Our research not only explores the impact of olive leaf extracts and glycerol as a plasticizer on biofilm solutions but also sheds light on increased opacity, reduced light absorption, and altered rheological properties. This endeavor aligns with the ongoing pursuit of sustainable packaging alternatives, emphasizing the crucial role of bioactive compounds in enhancing the functionality and eco-friendliness of biodegradable films.

The use of UV-A radiation for biofortification of lettuce and basil plants with antioxidant phenolic and flavonoid compounds

Stable plant production is a crucial concern of modern agriculture facing increasing food demands and the risk of less predictable weather conditions in the open field. Alternative approaches for plant production are greenhouses and indoor farming. Modern LED-based artificial lighting indoor facilities allow not only to fill the gap in the supply chain of food production, but to produce plants characterized with higher concentration of essential phytochemicals. Thus, in this study, we attempt to analyse the efficiency of short-term supplementation of spectrum within ultraviolet A light (UV-A, 365 nm) to increase the antioxidant potential of leafy plants, assessed by total phenolic (TPC) and flavonoid (TFC) content. To this end, two distinct cultivars of baby leaf lettuce (Lactuca sativa var. crispa L.) and microgreens basil (Ocimum basilicum L.) plants were grown under red-green-blue spectrum supplemented prior to harvest with low doses of UV-A radiation. Analyses showed that UV-A exposition enhanced TPC and TFC with green leaf cultivars, compared to dark-pigmented ones. The analysis also proved that plants exposed to UV-A presented higher overall antioxidant potential measured with 1,1-diphenyl-2-picrylhydrazil (DPPH). Results are crucial for better understanding the potential of UV-A supplementation to produce functional plants which are natural sources of dietary antioxidants.

Therapeutic and Pharmacological Properties of Pumpkin Seeds: A Comprehensive Review

A well-known edible plant in the Cucurbitaceae family, the pumpkin has long been utilized as a functional meal or a herbal remedy. Pumpkin seeds are rich in phytoestrogens, vitamin E, and unsaturated fatty acids, which may have medicinal and nutraceutical uses. The use of pumpkins in traditional medicine to treat a wide range of conditions, including inflammation, dyslipidemia, bacterial or fungal infections, malignancies, intestinal parasites, hypertension, arthritis, and hyperglycemia, has drawn attention to the need for additional study on both the fruits and seeds of the pumpkin plant. Proteins, antioxidative phenolic compounds, tocopherols, triterpenes, saponins, phytosterols, lignans, and carotenoids are some of the micro- and macro-constituent compositions that improve pumpkin seeds. Pumpkin seeds have antidepressant properties and are mostly used in the management of benign prostatic hyperplasia (BHP). Regular pumpkin seed eating lowers the risk of Parkinson's and Alzheimer's disease. Since pumpkin seeds are high in tocopherols, they can be extracted for edible oil and then used to formulate other foods at a later time. The pharmacological effects of pumpkin seeds have made them quite popular. Additionally, pumpkin seed oil has numerous health advantages. Pumpkin seeds are mostly composed of unsaturated fatty acids, which have been shown to provide potential health benefits and to prevent disease. Although pumpkin seeds are clearly very useful, their full potential has not yet been discovered.

Assessing the impact of cold plasma rotational dynamics on ginger's total phenolic content, antioxidant activity, surface structure and color using response surface methodology

This study investigated the efficacy of a rotational chamber in enhancing the effectiveness of cold plasma application to augment antioxidant activity and phenolic content in ginger (Zingiber officinale). To address the limitation of cold plasma (CP), which predominantly treats only the surface layers of samples, we implemented rotational techniques during the treatment. This methodology facilitates a more uniform treatment, ensuring that all layers of the samples are effectively exposed to plasma. We employed response surface methodology (RSM) to analyze the effects of three variables: power (10–90 W), treatment time (1–30 min), and pressure (0.4–0.9 mbar), along with a categorical variable for rotation. CP treatment (65 W, 0.7 mbar, 1 min with rotation) resulted in a significant increase in antioxidant activity compared to non-treated samples, determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric-reducing antioxidant power (FRAP), and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) ABTS assays, and total phenolic content reaching their highest values of 100.9 Trolox equivalent (TE) μmol⋅L−1, 8.23 Fe2+⋅g−1, 0.293 μmol⋅g−1, and 32.80 gallic acid equivalent (GAE)/g, respectively. There were no significant changes in color. Scanning Electron Microscopy (SEM) analysis revealed that the samples treated with CP exhibited a smoother surface, albeit with minimal damage to cell walls in our selected samples. Including a rotational feature as a unique upgrade to the cold plasma, the glow discharge device demonstrated positive enhancements and preservation of antioxidant activity and phenolic compounds.

Selective Extraction Process and Characterization of Antioxidant Phenolic Compounds from Pereskia aculeata Leaves Using UPLC-ESI-Q-TOF-MS/MS.

This study innovates in comparing biological activities and chemical composition obtained from extracts and fractions from Pereskia aculeate leaves. Seven extracts and five fractions were produced by conventional successive solid-liquid extraction coupled with simultaneous bioguided purification using solvents of distinct polarities. A comparative analysis was conducted between these purified fractions and the original extracts to elucidate potential improvements in the bioactivity. The extract and fractions were evaluated using the ABTS, DPPH, FRAP, and Folin-Ciocalteau methods and HPLC-DAD and UHPLC-ESI-Q-TOF-MS/MS evaluated chemical composition. The fractions obtained from the hydroalcoholic extract showed better results, with the acetone fraction (Fr-Ace) exhibiting enhanced bioactivity, especially in the FRAP (1095 μmol of FeSO4/g) antioxidant capacity method. The results demonstrated that medium to high polarity solvents were the most effective in extracting bioactive phenolic compounds, with rutin being the predominant compound. The sequential hydroalcoholic fractionation (SHF) method extracted a greater variety of compounds, including vanillic acid and cinnamic acid, which were reported for the first time in P. aculeate leaves. The identified compounds by UPLC-Q-TOF-MS/MS included flavonoids derived from quercetin, isorhamnetin, and kaempferol, phenolic acids, and their derivatives. Quercetin-3-O-xyloside, kaempferol-3-O-arabinoside, trehalose, feruloyltyramine, malyngic acid, pinellic acid, and 16-hydroxy-9-oxooctadeca-10,12,14-trienoic acid were identified for the first time in P. aculeata leaves.

Antioxidative properties, phenolic compounds, and invitro protective efficacy of multi-herbal hydro-alcoholic extracts of ginger, turmeric, and thyme against the toxicity of aflatoxin B1 on mouse macrophage RAW264.7 cell line.

Aflatoxin B1 (AFB1), the most potent toxic and carcinogenic secondary fungal metabolite, has frequently been reported in food/feed. Nowadays, herbal extracts are considered safe dietary additives to reduce the toxicity of such compounds. The protective capability of various combinations of hydro-alcoholic extracts (HAEs) of ginger, turmeric, and Shirazi thyme, against the toxicity of AFB1 on the RAW264.7 cell line was investigated. The RAW264.7 cells were exposed to six different concentrations of AFB1 (0.09, 0.18, 0.37, 0.75, 1.5, and 3 μg mL-1) for 48 h to determine the IC50 of AFB1. AFB1 was estimated to have an IC50 of 1.5 μg mL-1 for RAW264.7 cells. Then, the cells were simultaneously incubated with 1.5 μg mL-1 AFB1 and the HAEs for 24 h. The HAEs significantly reduced the toxicity of AFB1 in RAW264.7 cells. HAE of Shirazi thyme showed the highest amount of total phenol content (TPC) and the highest DPPH• activity. In addition, a combination of ginger, turmeric, and Shirazi thyme extract showed the highest antioxidant activity. Rutin, quercetin, and apigenin were the main phenolic components of ginger HAE. A significantly positive correlation was observed between TPC of hydro-alcoholic extract with ferric reducing antioxidant power (FRAP) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) values. Consequently, the simultaneous consumption of such extracts is recommended to protect the cells against dietary toxins.

Eugenia calycina and Eugenia stigmatosa as Promising Sources of Antioxidant Phenolic Compounds.

In this study, Eugenia calycina and Eugenia stigmatosa, native Brazilian berries, were explored regarding their proximal composition, bioactive compounds, and antioxidant activities. The edible parts of both fruits presented a low content of lipids, proteins, and carbohydrates, resulting in a low caloric value (<70 kcal/100 g fw). E. stigmatosa fruit showed a high total fiber content (3.26 g/100 g fw), qualifying it as a source of dietary fiber. The sugar profile was mainly monosaccharides (glucose, fructose, and rhamnose). Significant contents of total phenolics and flavonoids, monomeric anthocyanins and, condensed tannins, were observed in both fruits. E. calycina contains a high level of anthocyanins, primarily cyanidin-3-glucoside (242.97 µg/g). Other phenolic compounds were also found, the main ones being rutin and ellagic acid. In contrast, E. stigmatosa is mainly composed of rutin and gallic acid. Furthermore, these fruits showed expressive antioxidant activity, evidenced by ORAC, FRAP, and ABTS. These Eugenia fruits are promising sources of bioactive compounds and have a low caloric and high dietary fiber content, making them interesting options for inclusion in a balanced diet, contributing to the promotion of health and the valorization and conservation of Brazilian biodiversity.

Urban Air Pollution and Plant Tolerance: Omics Responses to Ozone, Nitrogen Oxides, and Particulate Matter.

Urban air pollution is a crucial global challenge, mainly originating from urbanization and industrial activities, which are continuously increasing. Vegetation serves as a natural air filter for air pollution, but adverse effects on plant health, photosynthesis, and metabolism can occur. Recent omics technologies have revolutionized the study of molecular plant responses to air pollution, overcoming previous limitations. This review synthesizes the latest advancements in molecular plant responses to major air pollutants, emphasizing ozone (O3), nitrogen oxides (NOX), and particulate matter (PM) research. These pollutants induce stress responses common to other abiotic and biotic stresses, including the activation of reactive oxygen species (ROSs)-scavenging enzymes and hormone signaling pathways. New evidence has shown the central role of antioxidant phenolic compound biosynthesis, via the phenylpropanoid pathway, in air pollution stress responses. Transcription factors like WRKY, AP2/ERF, and MYB, which connect hormone signaling to antioxidant biosynthesis, were also affected. To date, research has predominantly focused on laboratory studies analyzing individual pollutants. This review highlights the need for comprehensive field studies and the identification of molecular tolerance traits, which are crucial for the identification of tolerant plant species, aimed at the development of sustainable nature-based solutions (NBSs) to mitigate urban air pollution.

Antioxidant activity and phenolic content of bee breads from different regions of Türkiye by chemometric analysis (PCA and HCA)

The objective of this study was to assess the antioxidant activity and phenolic compounds of bee bread samples obtained from various regions in Türkiye The goal was to characterize and classify 15 of bee bread samples based on their geographical origins. This investigation employed chemometric techniques, specifically principal component analysis (PCA) and a hierarchical clustering algorithm (HCA), for the inaugural comprehensive analysis of all data encompassing antioxidant activity and phenolic compounds in bee bread. The primary objective was to unveil potential clustering patterns among of bee bread samples based on their geographical origins. According to the results, the Total Phenolic Content (TPC) of bee bread samples ranged from 4.393 to 14.917 mg GAE/g dw, while the Total Flavonoid Content (TFC) exhibited variation within the range of 0.681 to 3.504 mg QE/g dw. p-OH benzoic and p-coumaric acids were detected in all samples. Other phenolic compounds were identified in different proportions among the bee bread samples. This study demonstrated the successful application of the PCA chemometric method to assess the antioxidant activity and phenolic compounds of bee bread samples from various regions of Türkiye. The results revealed effective clustering of the bee bread samples based on their geographical origins.Graphical

Quantitative analysis of the phenolic compounds and antioxidant activities of six quinoa seed grains with different colors

To improve understanding of the potential benefits of quinoa as a staple food, the chemical composition, bioactive compounds, and total antioxidant capacity of six different colored quinoa cultivars were studied. The findings revealed that yellow quinoa exhibited a higher protein content, while white and red quinoa seeds contained greater amounts of starch, and black quinoa seeds were richer in fiber. A total of 20 phenolic compounds were identified, encompassing 13 phenolic acid variants and 7 flavonoid variants. The levels of phenolic acids (131.96–223.28 μg/g) and flavonoids (91.86–131.14 μg/g) exhibited variations based on seed color, with crimson and yellow quinoa seeds demonstrating the highest concentrations of both phenolic acids and flavonoids. Notably, crimson quinoa seeds displayed the highest content of betalains (36.17 μg/g). Saponin content was highest in yellow (178.82 mg/100 g), while the lowest in black (106.5 mg/100 g). Furthermore, it was observed that the phenolic acids present in red quinoa seeds exhibited the most potent DPPH free radical-scavenging ability. Conversely, black quinoa seeds displayed the highest iron-reducing antioxidant activity and ABTS free radical scavenging ability among all the samples examined. Moreover, black quinoa seeds demonstrated the highest overall antioxidant activity compared to other quinoa varieties This study suggests that colored quinoa seeds are rich in phenolic and betalains compounds with antioxidant capacity. The correlation analysis indicated a significant positive relationship between antioxidant activity and phenolic compounds up to a certain degree. As a result, colored quinoa can serve as an antioxidant food.

In Vitro Bioactivities of Cereals, Pseudocereals and Seeds: Assessment of Antiglycative and Carbonyl-Trapping Properties

Advanced glycation endproducts (AGEs) are the final products resulting from non-enzymatic glycation, which plays a crucial role in diabetes and aging-related health issues. The aim of the present investigation was to examine the inhibitory effects on AGE formation of aqueous and methanolic extracts from cereals (rice, rye, and wheat), pseudocereals (amaranth, quinoa, and buckwheat) and chia seeds. Different in vitro models simulating AGEs induced by glucose (Glc) and methylglyoxal (MGO) were evaluated. The MGO-trapping capacity of extracts was evaluated, alongside their antioxidant capacity and phenolic compound composition, with the aim of exploring any potential correlation with AGEs’ inhibitory effects. Extracts (25 mg/mL) demonstrated inhibitory effects on AGEs in protein–Glc and protein–MGO assays, with inhibition levels ranging from below 10% (amaranth extracts) to over 90% (buckwheat extracts) compared with aminoguanidine. Buckwheat methanolic extract exhibited the highest anti-AGE activity (98.3% inhibition in the BSA–Glc and 89.5% inhibition in the BSA–MGO assay), followed by chia seed extracts (80–82% inhibition). Buckwheat aqueous extract showed the greatest capacity to directly trap MGO (IC50 = 0.3 mg/mL). Antioxidants and phenolic compounds likely contributed to their antiglycative activity. In conclusion, aqueous and methanolic extracts derived from different natural ingredients such as cereals, pseudocereals, and seeds can be valuable in preventing glycation-related complications.