Phenolic Composition Research Articles

Unlocking the Hidden Potential of Rosemary (Salvia rosmarinus Schleid): New Insights into Phenolics, Terpenes, and Antioxidants of Mediterranean Cultivars

Rosemary (Salvia rosmarinus Schleid syn. Rosmarinus officinalis L.) is a Mediterranean aromatic species used both as an official herb and as a spice. Different cultivars may exhibit diverse phytochemical compositions, making a comprehensive chemical characterization pivotal for a targeted selection of valuable cultivars. This study aimed to characterize and compare the phenolic and terpene composition and content of leaf extracts of six Mediterranean rosemary cultivars: ‘Alba’, ‘Arp’ ‘Ginger’, ‘Gorizia’, ‘Tuscan Blue’, and ‘Roseus’. HPLC-DAD analysis revealed a similar phenolic composition in all the cultivars, but quantitative differences were observed. The main compounds were carnosic acid derivatives, flavonoids (e.g., luteolin, apigenin, and quercetin glucosides), rosmarinic acid, caffeic acid, and other hydroxycinnamic acid derivatives. The highest phenolic content was found in ‘Alba’, with a predominance of carnosic acid derivatives, whereas the lowest was found in ‘Ginger’ and ‘Gorizia’. The GC-MS analysis evidenced quantitative differences among the cultivars. Particularly, ‘Alba’ contained the highest terpene content, whereas ‘Arp’ and ‘Gorizia’ showed the lowest values. Regarding the antioxidant activity, ‘Alba’ exhibited the highest values as regards phenols, while for terpenes, the highest ones were obtained for ‘Ginger’ and ‘Tuscan Blue’. Significant Pearson correlations were obtained between the total phenol/terpene content and the antioxidant activity. The chemical characterization of these cultivars provides relevant information to produce the rosemary phytocomplexes, finding multiple industrial applications.

Comprehensive analysis of soybean (Glycine max L.) by-products: nutritional value, phenolic composition, and bioactive properties

Soybeans are key components in vegetable beverage production, generating two by-products: soybean hulls and okara. For every ton of soybeans, 50-80 kg of hulls and 120 kg of okara are produced, being often discarded or used in low-value applications like fertilizers or feed. This study aims at characterizing their biochemical and nutritional profiles to assess their potential reintroduction into the food chain. Both by-products have high levels of protein and dietary fiber, mainly insoluble. Okara and hulls predominantly contain oleic acid and linoleic acid, respectively. Seventeen phenolic compounds, mainly isoflavones, were identified, with genistein as the main compound. Hulls exhibit superior antioxidant activity compared to okara. Neither extract showed cytotoxicity or anti-inflammatory effects and exhibited limited antimicrobial activity. However, both demonstrate prebiotic potential, promoting beneficial gut bacteria growth. The results suggest that these by-products have significant potential as new ingredients for their protein, isoflavone, and fiber content, alongside prebiotic properties.

Polyphenol compounds contributing to the improved bioactivities of fermented Rubus chingii Hu

This research aims to evaluate the phenolic composition, antioxidant and enzyme inhibition activities of fermented Rubus chingii Hu wine, and explore the correlation between them. TPC (Total Phenolic content) and TFC (Total Flavonoid content) increased rapidly from 0 h to 72 h, followed by a slight decrease in TPC and a significant decrease in TFC. Fermentation could significantly increase the antioxidant activity and α-amylase/α-glucosidase enzyme inhibitory activity of Rubus chingii Hu. A total of 39 polyphenols and organic acids in fermented Rubus chingii Hu were identified by UPLC-ESI-Q-TOF-MS/MS and 11 of them were quantitatively analyzed. After fermentation, the contents of all the detected polyphenol compounds, except for quercetin and ellagic acid, significantly increased (p < 0.05). Correlation analysis showed that protocatechuic acid and catechin played an important role in the antioxidant activity of fermented Rubus chingii Hu, while protocatechuic acid and hypericin played an important role in the α-amylase inhibition activity. This study indicated that Rubus chingii Hu could be applided as a potential meterial for the wine production, and has the potential to be a functional food for promoting health.

Looking for the optimal harvest time of red grapes with an enzymatic electrochemical multisensory system

The timing of the grape harvest is a critical decision for winemakers, as it greatly impacts the quality and organoleptic characteristics of the resulting red wines. One key indicator for determining the optimal harvest time is the phenolic content of the grapes. As the berries ripen, phenolic compounds in the grape skin cells migrate from the seeds to the pulp and finally to the skin. However, monitoring these phenolic changes, particularly in the seeds, presents a challenge. This research addresses this problem by developing a novel technique to track the phenolic composition of seeds during ripening. The objective is to provide a reliable method for winemakers to monitor the phenolic evolution and improve harvest decision-making.In this study, a multisensory system consisting of four electrochemical enzymatic carbon paste sensors, modified with tyrosinase and electrocatalytic materials (AuNPs, lutetium phthalocyanine, and nickel oxide nanoparticles), was employed to analyze the phenolic content in grape seed extracts. The system monitored weekly changes in the phenolic composition of the seeds from three red grape varieties—Cabernet Sauvignon, Tempranillo, and Prieto Picudo—during their ripening from veraison to being overripe. Using voltammetric techniques, the electrochemical responses were characterized by shifts in peak positions and intensity changes, reflecting the oxidation/reduction of phenols. Principal Component Analysis (PCA) demonstrated the ability of the array of sensors to discriminate phenolic changes across ripening stages, while Partial Least Squares (PLS) regression provided robust correlation models between the electrochemical responses and seed phenolic content, with correlation coefficients ranging from 0.93 to 0.99. The developed methodology successfully tracked phenolic changes, offering a promising tool for monitoring grape seed maturation and assisting in determining the optimal harvest time.

The effects of Lamium garganicum subs lasioclades plant against fibroblast (U2OS cell), acetylcholinesterase, glutathione S-transferase; an in vitro, in silico study.

In this study, some biological activities extracts of Lamium garganicum subsp. lasioclades (Lgl) have been evaluated as well as identified the phenolic composition. Concentration ranges of 31.25, 62.5, 125, 250, and 500 µg/mL were applied to determine the extract's anti-cancer properties. Significant results were obtained against the osteosarcoma cell line (U2OS cell) compared to normal human umbilical vein endothelial cells (HUVEC). To determine the antioxidant activities ABTS, DPPH, FRAP, and CUPRAC methods were studied in vitro. Enzyme inhibition effects of methanol extract against the glutathione S-transferase (GST) and acetylcholinesterase (AChE) enzymes were investigated. IC50 values were calculated as 12.96 µL/ml for AChE and 13.02 µg/mL for GST respectively. The phenolic contents of the plant extract were analyzed by HPLC. The interaction mechanisms of protein-ligand complexes formed by Acetylcholinesterase (AChE) and Glutathione S-transferase (GST) receptors with Gallic acid and Rutin were investigated by molecular docking studies. The stability of the complexes formed between receptors and ligands was confirmed by root mean square deviation (RMSD), root mean square fluctuation (RMSF), number of average hydrogen bonding interactions (Hb), and radius of gyration (Rg) analyses obtained from 100ns molecular dynamics simulations.

Impact of artificial feeding on the phenolic composition of Mandaçaia honey (Melipona quadrifasciata)

This pioneering study explored juçara fruit formulations as an artificial feeding strategy for Mandaçaia bees (Melipona quadrifasciata) with three main objectives: to develop different juçara artificial feeding formulations, evaluate their acceptability by the bees, and assess their influence on the honey’s phenolic profile. Artificial feeding has been an increasingly valuable practice that supports bee nutrition and honey production, particularly in regions facing seasonal nectar shortages. Two groups of juçara-based formulations were designed: one using a juçara stock solution (1:1; m/v) diluted with water in varying proportions - T1 (50:50; v/v), T2 (30:70; v/v), and T3 (10:90; v/v), and another combining the juçara stock solution (1:1; m/v) with syrup - T4 (50:50; v/v), T5 (30:70; v/v), and T6 (10:90; v/v). Among these, T1 (A1) and T4 (A2) were chosen for the feeding trials, along a standard syrup solution as the control (A3). Feeding treatments A1 and A2 were associated with an increase in glycosylated compounds (hesperidin, rutin, kaempferol, and kaempferol-3-rutinoside) compared to control honey, suggesting potential deglycosylation of these compounds during honey maturation. Most samples met honey maturity standards, with one exception in the A1 group. Although a definitive statistical correlation between phenolic profile and specific feeding formulations was not established, juçara-based feedings significantly elevated total phenolic levels in the honey. These results provide critical insights into the application of juçara formulations, establishing a basis for future research into enhanced feeding strategies to optimize honey production and quality.

Effect of Different Extraction Techniques on Phenolic Profile and Phytochemical Potential of Gymnema inodorum Leaf Extract.

The therapeutic potential of plant extracts has attracted significant interest, especially regarding indigenous species with health-promoting properties. Gymnema inodorum, native to Northern Thailand, is recognized for its rich phytochemical profile; however, the impact of various extraction techniques on its phenolic composition and bioactivity remains underexplored. Optimizing extraction methods is essential to enhance the pharmacological efficacy of this plant's bioactive compounds. This study investigated the influence of four extraction methods-ethanol maceration, ethanol reflux, aqueous decoction, and microwave-assisted extraction-on the bioactive profile of G. inodorum leaves, with a focus on the phenolic content and biological activities. Antioxidant activities were evaluated using DPPH, ABTS, and FRAP assays, while the total phenolic and flavonoid contents were quantified by colorimetric methods. High-Performance Liquid Chromatography (HPLC) quantified gymnemic acid and key phenolic compounds. Among the methods, ethanol reflux yielded the highest antioxidant activities (DPPH and ABTS scavenging), with a total phenolic content of 82.54 mg GAE/g and flavonoid content of 31.90 mg QE/g. HPLC analysis identified sinapic acid, myricetin, and p-hydroxybenzoic acid as major phenolics. Furthermore, the ethanol reflux extract displayed potent anti-diabetic activity, with IC50 values of 13.36 mg/mL for α-amylase and 7.39 mg/mL for α-glucosidase, as well as strong anti-inflammatory activity (IC50 of 1.6 mg/mL) and acetylcholinesterase inhibition (IC50 of 1.2 mg/mL). These findings suggest that ethanol reflux extraction is a highly effective method for producing bioactive-rich G. inodorum extracts, with substantial pharmacological potential for developing herbal remedies and nutraceuticals, particularly in enhancing therapeutic approaches for diabetes and other health-related conditions.

First Experience of Late Pruning on Kékfrankos Grapevine (Vitis vinifera L.) in Eger Wine Region (Hungary)

Traditional winter pruning in dormancy (BBCH-00) as control (C) and three late pruning treatments, LP1 (wool stage—BBCH-05), LP2 (two leaves folded—BBCH-12), and LP3 (four leaves folded—BBCH-14), were applied on Kékfrankos grapevines. The evolution of the phenological growth stages, grape juice, wine analytical parameters, and phenolic composition were evaluated. The quantitative aspects of the grape berry, bunch, yield, and cane were also assessed. Our goal was to reach a decrease in sugar content and an increase in acidity. Delaying or postponing the phenological phases to bring technological and phenolic ripening closer together was also one of our objectives. These were accomplished, but the negative aspects of late pruning, which resulted in a reduction in the diameter and weight of the canes, should also be taken into account. We also found that, the later the late pruning, the more the yield was reduced. By postponing pruning, the phenological phases were also extended.

Assessment of the germination power and α-amylase activity in the soil rhizospheric compartment amended with olive mill waste waters.

Olive mill wastewater (OMWW) was used in ferti-irrigation due to its high water content, as well as its organic and mineral richness. However, this by-product also contains elevated levels of polyphenols, which may pose phytotoxic risks to soil microbiota and plants over time. To address this concern, we conducted a thorough examination of the phenolic composition of OMWW and the phenolic content of amended soils using HPLC analysis. Additionally, we assessed the residual phytotoxicity of OMWW across various soil rhizospheric layers (0-30 cm, 30-60 cm, and 60-90 cm). Standard germination tests were performed using soil extracts with sorghum (Sorghum bicolor) and tomato (Solanum lycopersicum) seeds. We also measured α-amylase activities in the germinated seeds for both species, comparing them to raw OMWW and control soil extracts. HPLC analysis revealed that tyrosol, ferulic acid, and hydroxytyrosol were the predominant phenolic compounds in crude OMWW, while no detectable compounds were found in the soil extracts. Germination tests indicated minimal toxicity in the topsoil amended with OMWW, with a noticeable reduction in residual phytotoxicity at greater depths. These results aligned with the α-amylase activity assessments, which demonstrated significantly higher enzyme activity in the deeper soil layers (30-60 cm and 60-90 cm), with no substantial differences compared to control extracts.

Composition of the Low Molecular Weight Metabolome of Potamogeton perfoliatus (Potamogetonaceae) as an Indicator of the Transformation of the Ecological State of the Littoral Zone

The composition and nature of changes in the low-molecular-weight metabolome (NM) of Potamogeton perfoliatus L., growing in 6 biotopes of Lake Ladoga with different types of the anthropogenic load has been analyzed. According to the research results, it was found that the total number of low molecular weight organic compounds (LMWOCs) in the P. perfoliatus NM composition is directly dependent on anthropogenic load, which is well marked by the development of cyanobacteria. The greater the intensity of pollution or eutrophication of waters, or the higher the number of cyanobacteria, the lower the total number of LMWOCs and their concentration. A strongly pronounced dependence of the total concentrations of groups of NM compounds on the anthropogenic disturbance of the biotope and the concentration of cyanobacteria was revealed. A decrease in the number, relative amount, total concentration of carboxylic acids, number and content of unsaturated fatty acids, and, at the same time, an increase in the composition and content of phenols and the total content of aldehydes and ketones depends on an increase in anthropogenic pressure. The specific composition of NM of pierced pondweed depends on its response to biotic and abiotic factors of the aquatic environment, including anthropogenic ones. The revealed features of the change in the composition of P. perfoliatus NM make it possible to use it as an integral indicator of the anthropogenic impact on the littoral biotopes of water bodies and the deterioration of their ecological state.

Influence of Microbial Treatments on Vine Growth and Must Quality: Preliminary Results.

Microorganisms play a crucial role in addressing the challenges related to the increasing detrimental effects of intensive agriculture in vineyards by contributing to various aspects, from maintaining soil health and vine vitality to influencing fermentation and the overall wine features. Among microorganisms, mycorrhizal fungi are widely distributed in both natural and agricultural ecosystems, and their mutually beneficial relationship with most terrestrial plants provides valuable ecological benefits. Nowadays, the wine industry is increasingly moving toward the production of organic wines, highlighting the need for novel and healthier strategies that prioritize both the consumer well-being and the quality of the final wine product. Following our previous study in collaboration with the Bioma SA Company (Quartino, Switzerland), the investigation was continued by extending the organic practice to the cultivation. The present work, indeed, aimed to evaluate the influence of the treatment with mycorrhizal fungi on the metabolism of "Sangiovese" grapevines. In particular, the chemical parameters, including alcohol content, pH, acidity, phenolic composition, and sulfur dioxide, were assessed on the must, while the analysis of the volatile emission was conducted both on whole and pressed grapes, on must, as well as on the grape skins. To the best of our knowledge, this is the first study investigating the mycorrhizal fungi association effect on the quality of "Sangiovese" grapes and, further, its effect on the VOCs emission.

Endemic Plant Rumex balcanicus: Phenolic Composition, Antioxidant Activity, Enzyme Inhibitory Potential and Molecular Docking Analysis.

Although the nutritional and health benefits of Rumex species are well known, little is known about the chemical composition and pharmacological activities of Rumex balcanicus Rech. fil. (Polygonaceae), an endemic plant of the Balkan Peninsula. To the best of our knowledge, this paper represents the first attempt to comparatively analyse phenolic composition, as well as in vitro pharmacological activites of dry hydromethanol extracts of R. balcanicus fruit (RBF), leaf (RBL) and root (RBR), collected in Serbia. The maximum total phenolic content was found in RBF (386.6 mg GAE/g). The RBF was characterized by high amounts of miquelianin (28.8 mg/g) and procyanidin B1 (28.1 mg/g). The RBL was the richest in quercitrin (18.4 mg/g) and miquelianin (15.0 mg/g), while nepodin (54.1 mg/g) and procyanidin B2 (40.6 mg/g) were the major compounds in RBR. The RBF exhibited significant antioxidant activity, evaluated by DPPH (IC50=4.9 μg/mL), ABTS (IC50=0.8 μg/mL) and FRAP (5.9 mmol Fe2+/g) assays. Moreover, RBF showed strong α-glucosidase inhibitory activity (IC50=1.8 μg/mL), in addition to notable anti-α-amylase, anti-acetylcholinesterase and anti-tyrosinase activities. Molecular docking analysis predicted miquelianin and procyanidin B2 as the greatest inhibitors of these enzymes. Overall, R. balcanicus fruits stood out as the most promising plant material worth further research.

Argentine Malbec market: comparative study of general chemical parameters and sensory properties within low, medium and high price segments

Malbec, Argentina's emblematic wine, is appreciated worldwide for its unique characteristics and distinctive organoleptic profile. As demand for Malbec wines increases locally in Argentina and international markets, there is a need to better understand the relationship between the price of these wines and their chemical and sensory characteristics. The aim of this study was to describe and quantify the sensory attributes and chemical parameters (in particular, phenolics) of Argentinean Malbec wines of different price segments. In order to observe the differences between each price range, the eight best-selling wines from the low, medium, and high price categories were analysed. Wine general analytical parameters and phenolics composition were determined and a descriptive analysis was performed with a trained panel. The results show that it was only possible to differentiate between the high- and low-price ranges. Both ranges exhibited variability, including different types of wines. Significant differences were identified in several parameters, such as O.D.280, titratable acidity, malic acid, volatile acidity, alcohol, glucose and total sugars. There were also significant differences in anthocyanins, LPP, SPP, TPP and tannins. The high-price range was characterised by higher alcohol content, greater polyphenol concentration and greater colour intensity. Sensorially, they were distinguished by the descriptors wood, astringency and colour. The low-price range was associated with low colour intensity and higher total sugar content. This is the first study to clearly establish the sensory differences among different price ranges of Argentine wines. Our study demonstrated that wine pricing is not determined in a subjective or arbitrary manner; rather, wines produced for a specific segment are intentionally designed to achieve the desired sensory and chemical characteristics.

Polysaccharide-induced colloidal stabilization of red wines: Impact on phenolic composition and color characteristic

Polysaccharides play a crucial role in wine quality and colloidal stability. Two types of polysaccharides were applied to three wines with diverse initial phenolic and polysaccharide profiles to evaluate their effects on the color characteristics of the wines. Changes in the colloidal properties, phenolic composition, and color parameters of the wines were analyzed over a one-year bottle aging. The results revealed that the addition of polysaccharides consisting mainly of arabinogalactans (AG) tended to have a higher absolute zeta (ζ) potential value (below −10 mV), indicative of enhanced colloidal stability, while mannoprotein (MP) had little effect. However, the addition of both polysaccharides can influence the colloidal particle size and turbidity of the wines, with distinct variations observed based on the initial matrix composition, especially the polysaccharide content. Furthermore, both polysaccharides promoted the formation and accumulation of anthocyanin derivatives, especially pyranoanthocyanin, while AG had a greater effect, with a maximum increase of nearly 14% compared with the control group at 12 M. The color characteristic of the wines changed accordingly, with a significant increase in the red hue (a∗ value), particularly in wines characterized by low polysaccharide content and high polyphenol level. Notably, the modifications in colloidal properties induced by polysaccharide displayed a significant correlation with polyphenols and color parameters, indicating that a stable colloidal system facilitates color stability. In practical winemaking applications, the addition of polysaccharides should consider factors such as their type, concentration, and the balance of the initial wine composition.

Structured Fruit Cube Snack of BRS Vitoria Grape with Gala Apple: Phenolic Composition and Sensory Attributes.

This study developed a structured fruit cube (FC) snack using only natural ingredients, specifically red grape and apple, without hydrocolloids and sucrose. After development, physicochemical characterization and analysis of phenolic compounds (PCs), including anthocyanins, flavonols, and hydroxycinnamic acid derivatives, using HPLC-DAD-ESI-MS/MS, were conducted. Sensory quality was also assessed through an acceptance and sensory profile analysis using the rate-all-that-apply methodology. The results showed that the FC had physicochemical characteristics similar to other structured fruits that use hydrocolloids. Additionally, they presented a complex composition of PCs, predominantly including anthocyanins derived from malvidin (tri-substituted methoxylated anthocyanins), notably cumarylated ones. Flavonols compounds comprised the 3-glucoside series of myricetin, quercetin, laricitrin, kaempferol, isorhamnetin, and syringetin; the 3-galactoside series of myricetin and quercetin; and the 3-glucuronic acid series of myricetin and quercitin, along with rutin. The presence of caftaric acid, coutaric acid, fertaric acid, and p-coumaroyl-glucose was also detected, alongside caffeic acid-O-glucoside 1, caffeic acid-O-glucoside 2, chlorogenic acid, 4-O-p-coumaroylquinic acid, and dicaffeoylquinic acid. In conclusion, the selection of natural ingredients was technologically suitable for obtaining an FC. Despite using conventional drying at 60 °C, the product showed notable concentrations of PCs and also achieved great sensory acceptance.

Comparative assessment of antioxidant activity in red apricot (Prunus armeniaca L.) and Fig fruits (Ficus carica L.) cultivated in Nakhchivan AR, Azerbaijan

Red apricot (Prunus spp.) and Black Fig (Ficus carica L.) are two of the most commonly grown summer fruits in the Nakhchivan region. In this preliminary study, ethanol fruit extracts were compared based on their total phenolic content (TPC) and antioxidant properties. According to the Folin-Ciocalteu method, the TPC was found to be 176.20 mg GAE/100 g in red apricot and 45.30 mg GAE/100 g in fig. Their antioxidant capacities were assessed using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. The scavenging activity, identified as the concentration of ethanol extract needed to scavenge half of the radicals (SC50), was determined to be 3.52 mg/mL for red apricot and 6.46 mg/mL for fig. Based on these two biological activity assays, red apricot exhibited higher phenolic composition and radical scavenging activity. However, further studies are required to understand whether these differences are attributed to secondary metabolites in these fruits.

Assessment of In Vitro Antioxidant Activity and Phenolic Composition in Peels of Ten Native Potato Cultivars from Cusco

Assessment of In Vitro Antioxidant Activity and Phenolic Composition in Peels of Ten Native Potato Cultivars from Cusco

Effects of different processing methods on phenolic compounds in flaxseed meal

This study examined effects of different processing methods on phenolic compounds in flaxseed meal. The optimal SE treatment was 1.0 MPa for 3 min, and the contents of total flavonoids and phenolic acid were 2.26 times and 1.63 times of the control group, respectively. Notably, erucic acid increased 85.76 %. Optimal extrusion conditions (15 % moisture content, 140 °C, 29 hz) led to the presence of rutin and a 2.81 times increase in protocatechuic acid content over the control. Fermenting with 3 % Bacillus subtilis for 4 days yielded gallic acid in bound form and vanillic acid in free form, with protocatechuic acid increasing 40.65 % compared to the control. Among all the treatments, extrusion produced the highest levels of phenolic compounds in flaxseed meal. Each treatment significantly increased the open ring isomer ester phenol (SDG) compared to the control. Overall, various processing methods impacted the phenolic content and composition in flaxseed meal differently.

A Comprehensive Evaluation of Chemical, Bioactive Profile, and Anti-oxidant Potential of Gabiroba (Campomanesia cambessedeana): An Underexplored Fruit from Brazil

Background: The Cerrado region has one of the world's largest and most diverse tropical biodiversity, hosting several species of exotic fruits little explored. In this context, we can highlight the gabiroba (Campomanesia cambessedeana), a native fruit tree belonging to the Myrtaceae family. However, its fruits are not used frequently, except by the local population who consume them, and are also reported as nutritional. Objective: This work evaluated the chemical composition of the whole fruit, pulp, peel, and seed of gabiroba. Methods: Physicochemical characterization, bioactive compounds and antioxidant potential, and mineral profile (ICP-OES) were evaluated. Individual phenolic compounds and organic acids by liquid chromatography (HPLC-DAD) of the pulp, peel, and seed fractions of gabiroba were also explored. Results: The results showed that the gabiroba fruit has a low lipid content (1.09 g 100 g-1), high magnesium content (12.60 μg g-1), and significant values of total phenolics (153.17 mg EAG 100 g-1), vitamin C (51.20 mg AA 100 g-1) and antioxidant potential by DPPH radical scavenging (15.35 g sample g-1 DPPH). The analysis of organic acids showed that the pulp and peel are rich in malic acid (7.29 and 8.15 mg 100 g-1, respectively) and the seed in citric acid (10.26 mg 100 g-1). On the other hand, both pulp, peel, and seed fractions showed similar individual phenolic composition, mainly being composed of catechin (3.36, 2.71, and 2.70 mg 100 g-1), gallic acid (1.67, 1.66, and 1.68 mg 100 g-1) and rutin (0.85, 1.39 and 1.16 mg 100 g-1, respectively). Conclusion: The individual phenolics in the gabiroba fractions may have been responsible for the high antioxidant activity. In this way, gabiroba has demonstrated its technological potential for its full use in producing food products and applications in the pharmaceutical and cosmetics industry.

Isolation, Purification, and Antioxidant Activity of Polyphenols from Cynanchum auriculatum Royle ex Wight

Cynanchum auriculatum Royle ex Wight (CA) is a traditional medicinal and edible plant in China. This study aimed to isolate and characterize the phenolic compounds of C. auriculatum to identify its main antioxidant constituents. Polyphenols were extracted using an ultrasound-assisted ethanol extraction method, followed by partitioning with ethyl acetate. The ethyl acetate extract was then purified through thin-layer chromatography, silica gel column chromatography, and reverse-phase silica gel column chromatography. Three monomeric compounds—cynandione A (I), 2,5-dihydroxyacetophenone (II), and radix piperacanthone (III)—were identified through their physical and chemical properties, UV and IR spectra, and liquid chromatography–mass spectrometry (LC-MS/MS). Vitamin C (VC) and 2,4-dihydroxyacetophenone were used as controls to evaluate the antioxidant potential of the two most abundant monomers. Antioxidant assays demonstrated that 2,5-dihydroxyacetophenone and cynandione A exhibited strong antioxidant activity at lower concentrations, whereas 2,4-dihydroxyacetophenone showed significantly weaker activity. Furthermore, cynandione A displayed superior cellular antioxidant activity compared to 2,5-dihydroxyacetophenone, indicating its potential as a promising bioactive compound. In conclusion, this study provides valuable insights into the phenolic composition of C. auriculatum and highlights cynandione A as a key antioxidant, paving the way for future research on its therapeutic applications.