Antioxidant capacity and total phenolics of Cyphostemma digitatum before and after processing: use of different assays

Unlocking the potential of biostimulants in sustainable agriculture: Effect of wood distillate on the nutritional profiling of apples

In this work, we report the investigation of the effect of exposure of apple trees to the bioeffector wood distillate (WD), a plant biostimulant used for improving the nutritional profiling of crop plants. We measured the effect by evaluating the biochemical and nutritional profile of both pulps and skin of fruits. WD (0.2 %, v/v) was applied once a week by foliar application, from May 2023 until September 2023. The results indicate that the WD-treated apples have a significant increase in several analyzed parameters (i.e., phenols, flavonoids, tannins, total antioxidant power, sugars, pectin, free amino acids, and mineral element content), especially in the pulp. These data were also confirmed by NMR and LC-ESI-MS techniques. This study pointed out that WD could be a handy tool for the cultivation of fruit trees.

Effect of Physical Separation with Ultrasound Application on Brewers' Spent Grain to Obtain Powders for Potential Application in Foodstuffs

Brewers' spent grain (BSG) is the primary by-product of beer production, and its potential use in food products is largely dependent on its processing, given its moisture content of up to 80%. This study aimed to evaluate the effects of physical separation with ultrasound application on the color, total phenolic content (TPC), antioxidant activity, proximate composition, total dietary fibers, and particle size distribution of BSG powders. Wet BSG (W) was subjected to two processes: one without ultrasound (A) and one with ultrasound (B). Both processes included pressing, convective air-drying, sieving, fraction separation (A1 and B1 as coarse with particles ≥ 2.36 mm; A2 and B2 as fine with particles < 2.36 mm), and milling. The total color difference compared to W increased through both processes, ranging from 1.1 (B1 vs. A1) to 5.7 (B1 vs. A2). There was no significant difference in TPC, but process B powders, particularly B2, showed lower antioxidant activity against ABTS•+, likely due to the release of antioxidant compounds into the liquid fraction during pressing after ultrasound treatment. Nonetheless, process B powders exhibited a higher content of soluble dietary fibers. In conclusion, ultrasound application shows potential for further extraction of soluble fibers. However, process A might be more practical for industrial and craft brewers. Further studies on the use of the resulting BSG powders as food ingredients are recommended.

Biological activity of optimized phenolic extracts of quince (Cydonia oblonga Miller) parts before and after simulated in vitro gastrointestinal digestion

In this study, the phenolic extracts of Eşme quince parts (pulp, peel, seed, juice, and leaf) were obtained under optimized extraction conditions. Then, the total phenolic content (TPC), the quantities of main phenolic compounds, antioxidant, and antimicrobial activity and the change in bioactivity properties (TPC, antioxidant capacity, and antimicrobial activity on the same sixteen microorganisms) after in vitro digestion of each quince part were evaluated. The order of TPC and antioxidant activity was determined as leaf > peel > juice > pulp > seed. After in vitro gastrointestinal digestion, a decrease was observed for the TPC (average 5-fold reduction) and antioxidant activity (more than 2.5-fold reduction) in all quince parts except quince seed than their extract forms. The quince leaf extract exhibited the highest antibacterial activity. Overall, this study exhibited that the quince leaf was considered a promising, cheap, and natural source for nutritional or pharmaceutical applications with biological activity properties.

Bioactive Compounds and Potential Health Benefits through Cosmetic Applications of Cherry Stem Extract

Cherry stems, prized in traditional medicine for their potent antioxidant and anti-inflammatory properties, derive their efficacy from abundant polyphenols and anthocyanins. This makes them an ideal option for addressing skin aging and diseases. This study aimed to assess the antioxidant and anti-inflammatory effects of cherry stem extract for potential skincare use. To this end, the extract was first comprehensively characterized by HPLC-ESI-qTOF-MS. The extract's total phenolic content (TPC), antioxidant capacity, radical scavenging efficiency, and its ability to inhibit enzymes related to skin aging were determined. A total of 146 compounds were annotated in the cherry stem extract. The extract effectively fought against NO· and HOCl radicals with IC50 values of 2.32 and 5.4 mg/L. Additionally, it inhibited HYALase, collagenase, and XOD enzymes with IC50 values of 7.39, 111.92, and 10 mg/L, respectively. Based on the promising results that were obtained, the extract was subsequently gently integrated into a cosmetic gel at different concentrations and subjected to further stability evaluations. The accelerated stability was assessed through temperature ramping, heating-cooling cycles, and centrifugation, while the long-term stability was evaluated by storing the formulations under light and dark conditions for three months. The gel formulation enriched with cherry stem extract exhibited good stability and compatibility for topical application. Cherry stem extract may be a valuable ingredient for creating beneficial skincare cosmeceuticals.

Antioxidant and antiproliferative effect of a glycosaminoglycan extract from Rapana venosa marine snail

Marine glycosaminoglycans (GAG) isolated from different invertebrates, such as molluscs, starfish or jellyfish, have been described as unique molecules with important pharmacological applications. Scarce information is available on GAG extract from Rapana venosa marine snail. The aim of this study was to isolate a GAG extract from R. venosa marine snail and to investigate its physicochemical, antioxidant and antiproliferative properties for further biomedical use. The morphology, chemical and elemental composition of the extract were established as well as the sulfate content and N- to O-sulfation ratio. Fourier transform infrared (FTIR) spectra indicated that GAG extract presented similar structural characteristics to bovine heparan sulfate and chondroitin sulfate. The pattern of extract migration in agarose gel electrophoresis and specific digestion with chondroitinase ABC and heparinase III indicated the presence of a mixture of chondroitin sulfate-type GAG, as main component, and heparan sulfate-type GAG. Free radical scavenging and ferric ion reducing assays showed that GAG extract had high antioxidant activity, which slightly decreased after enzymatic treatment. In vitro MTT and Live/Dead assays showed that GAG extract had the ability to inhibit cell proliferation in human Hep-2 cell cultures, at cytocompatible concentrations in normal NCTC clone L929 fibroblasts. This capacity decreased after enzymatic digestion, in accordance to the antioxidant activity of the products. Tumoral cell migration was also inhibited by GAG extract and its digestion products. Overall, GAG extract from R. venosa marine snail exhibited antioxidant and antiproliferative activities, suggesting its potential use as novel bioactive compound for biomedical applications.

Microencapsulation of Mitragyna leaf extracts to be used as a bioactive compound source to enhance in vitro fermentation characteristics and microbial dynamics

OBJECTIVE

Mitragyna speciosa Korth is traditionally used in Thailand. They have a high level of antioxidant capacities and bioactive compounds, the potential to modulate rumen fermentation and decrease methane production. The aim of the study was to investigate the different levels of microencapsulated-Mitragyna leaves extracts (MMLE) supplementation on nutrient degradability, rumen ecology, microbial dynamics, and methane production in an in vitro study.

METHODS

A completely randomized design was used to assign the experimental treatments, MMLE was supplemented at 0%, 4%, 6%, and 8% of the total dry matter (DM) substrate.

RESULTS

The addition of MMLE significantly increased in vitro dry matter degradability both at 12, 24, and 48 h, while ammonia-nitrogen (NH3-N) concentration was improved with MMLE supplementation. The MMLE had the greatest propionate and total volatile fatty acid production when added with 6% of total DM substrate, while decreased the methane production (12, 24, and 48 h). Furthermore, the microbial population of cellulolytic bacteria and Butyrivibrio fibrisolvens were increased, whilst Methanobacteriales was decreased with MMLE feeding.

CONCLUSION

The results indicated that MMLE could be a potential alternative plant-based bioactive compound supplement to be used as ruminant feed additives.

Chicken viscera meal as substrate for the simultaneous production of antioxidant compounds and proteases by Aspergillus oryzae

The use of chicken waste can contribute to the development of new processes and obtaining molecules with high added value. An experimental design was applied to evaluate the effect of moisture, temperature, and inoculum size on the production of antioxidant peptides and proteases by A. oryzae IOC3999 through solid-state fermentation (SSF) of chicken viscera meal. As a result, the process conditions strongly influenced protease production and antioxidant activity of the fermented products. A global analysis of the results indicated that the most adequate conditions for SSF were (assay 9): 40% initial moisture, 30 °C as the incubation temperature, 5.05 × 106 spores/g as the inoculum size, and 48-h fermentation as the fermentation time. Under this condition, the antioxidant activities for the ABTS- and DPPH-radicals inhibition and ferric reducing antioxidant power (FRAP) methods were 376.16, 153.29, and 300.47 (µmol TE/g), respectively, and the protease production reached 428.22 U/g. Ultrafiltration of the crude extract obtained under optimized fermentation conditions was performed, and the fraction containing peptides with molecular mass lower than 3 kDa showed the highest antioxidant activity. The proteases were biochemically characterized and showed maximal activity at pH values ranging from 5.0 to 6.0 and a temperature of 50 °C. The thermodynamic parameters indicated that the process of thermal protease inactivation is not spontaneous (ΔG*d > 88.78 kJ/mol), increasing with temperature (ΔH*d 27.01-26.88 kJ/mol), and with reduced disorder in the system (ΔS*d <  - 197.74 kJ/mol) probably caused by agglomeration of partially denatured enzymes.

The Potential of Mangifera indica L. Peel Extract to Be Revalued in Cosmetic Applications

The constant growth of the cosmetic industry, together with the scientific evidence of the beneficial properties of phytochemicals, has generated great interest in the incorporation of bioactive extracts in cosmetic formulations. This study aims to evaluate the bioactive potential of a mango peel extract for its incorporation into cosmetic formulations. For this purpose, several assays were conducted: phytochemical characterization; total phenolic content (TPC) and antioxidant potential; free-radical scavenging capacity; and skin aging-related enzyme inhibition. In addition, the extract was incorporated into a gel formulation, and a preliminary stability study was conducted where the accelerated (temperature ramp, centrifugation, and heating/cooling cycles) and long-term (storage in light and dark for three months) stability of the mango peel formulations were evaluated. The characterization results showed the annotation of 71 compounds, gallotannins being the most representative group. In addition, the mango peel extract was shown to be effective against the •NO radical with an IC50 of 7.5 mg/L and against the hyaluronidase and xanthine oxidase enzymes with IC50 of 27 mg/L and 2 mg/L, respectively. The formulations incorporating the extract were stable during the stability study. The results demonstrate that mango peel extract can be a by-product to be revalorized as a promising cosmetic ingredient.

Food Monitoring: Limitations of Accelerated Storage to Predict Molecular Changes in Hazelnuts (Corylus avellana L.) under Realistic Conditions Using UPLC-ESI-IM-QTOF-MS

Accelerated storage is routinely used with pharmaceuticals to predict stability and degradation patterns over time. The aim of this is to assess the shelf life and quality under harsher conditions, providing crucial insights into their long-term stability and potential storage issues. This study explores the potential of transferring this approach to food matrices for shelf-life estimation. Therefore, hazelnuts were stored under accelerated short-term and realistic long-term conditions. Subsequently, they were analyzed with high resolution mass spectrometry, focusing on the lipid profile. LC-MS analysis has shown that many unique processes take place under accelerated conditions that do not occur or occur much more slowly under realistic conditions. This mainly involved the degradation of membrane lipids such as phospholipids, ceramides, and digalactosyldiacylglycerides, while oxidation processes occurred at different rates in both conditions. It can be concluded that a food matrix is far too complex and heterogeneous compared to pharmaceuticals, so that many more processes take place during accelerated storage, which is why the results cannot be used to predict molecular changes in hazelnuts stored under realistic conditions.

Transcriptomic and physiological approaches to decipher cold stress mitigation exerted by brown-seaweed extract application in tomato

Chilling temperatures represent a challenge for crop species originating from warm geographical areas. In this situation, biostimulants serve as an eco-friendly resource to mitigate cold stress in crops. Tomato (Solanum lycopersicum L.) is an economically important vegetable crop, but quite sensitive to cold stress, which it encounters in both open field and greenhouse settings. In this study, the biostimulant effect of a brown-seaweed extract (BSE) has been evaluated in tomato exposed to low temperature. To assess the product effects, physiological and molecular characterizations were conducted. Under cold stress conditions, stomatal conductance, net photosynthesis, and yield were significantly (p ≤ 0.05) higher in BSE-treated plants compared to the untreated ones. A global transcriptomic survey after BSE application revealed the impact of the BSE treatment on genes leading to key responses to cold stress. This was highlighted by the significantly enriched GO categories relative to proline (GO:0006560), flavonoids (GO:0009812, GO:0009813), and chlorophyll (GO:0015994). Molecular data were integrated by biochemical analysis showing that the BSE treatment causes greater proline, polyphenols, flavonoids, tannins, and carotenoids contents.The study highlighted the role of antioxidant molecules to enhance tomato tolerance to low temperature mediated by BSE-based biostimulant.

Sunflower and Palm Kernel Meal Present Bioaccessible Compounds after Digestion with Antioxidant Activity

Sunflower (Helianthus annuus L.) and African palm kernel (Elaeis guineensis Jacq.) are among the most cultivated in the world regarding oil extraction. The oil industry generates a large amount of meal as a by-product, which can be a source of nutrients and bioactive compounds. However, the physiological effects of bioactive compounds in such matrices are only valid if they remain bioavailable and bioactive after simulated gastrointestinal digestion. This study evaluated the chemical composition and antioxidant and prebiotic potential of de-oiled sunflower (DS) and de-oiled palm kernel (DP) meal after in vitro digestion. The DS sample had the highest protein content and the best chemical score, in which lysine was the limiting amino acid. Digested samples showed increased antioxidant activity, measured by in vitro methods. The digested DS sample showed a better antioxidant effect compared to DP. Moreover, both samples managed to preserve DNA supercoiling in the presence of the oxidizing agent. The insoluble fractions after digestion stimulated the growth of prebiotic bacterium, similar to inulin. In conclusion, simulated gastrointestinal digestion promoted in both matrices an increase in protein bioaccessibility and antioxidant capacity, pointing to a metabolic modulation favorable to the organism.

Germination and its role in phenolic compound bioaccessibility for black mustard grains: A study using INFOGEST protocol

Germination has been regarded as a promising natural process to improve the antioxidant properties of mustard. However, there ís one question to be solved in this area: does germination improve mustard phenolics' bioaccessibility? The aim of this study was to answer this question by using INFOGEST protocol to simulate in vitro digestion. Resveratrol, formononetin and cryptochlorogenic acid were identified for the first time as evaluated by liquid chromatography-mass spectrometry. In general, digestion positively impacted the antioxidant potential of soluble phenolics from non-germinated and germinated grains, which were probably released from cell wall matrix by digestive enzymes. Although digestion seemed to nullify the antioxidant improvement caused by germination, phenolic quantities were distinctive. The main difference was found for sinapic acid, as its concentration reached a value 1.75-fold higher in germinated digested mustard compared to non-germinated. The results obtained suggested that germination improved the phenolic bioaccessibility of mustard grains, which encourages its use and investigations.

3D-Printed, Liquid-Filled Capsules of Concentrated and Stabilized Polyphenol Epigallocatechin Gallate, Developed in a Clinical Trial

In vitro studies have shown that epigallocatechin gallate (EGCG), the most potent antioxidant of the green tea polyphenol catechins, is able to effectively prevent the formation of amyloid plaques and induce their clearance. However, its high chemical reactivity promotes high chemical instability, which represents a major obstacle for the development of pharmaceutical forms containing solubilized EGCG, an essential condition for a better systemic passage via the oral route. After discovering that EGCG forms a deep eutectic with choline chloride, we exploited this property to formulate and patent liquid-filled capsules containing 200-800 mg of soluble EGCG in easy-to-administer sizes. The gelatin envelopes used are of the conventional type and their filling has been achieved using 3D printing technology. Not only did the EGCG-choline complex allow the formulation of hydrophilic solutions with a high concentration of active substance but it also contributed significantly to its chemical stability, since after at least 18 months of storage at 25 °C/60% RH and one year at 40 °C/75% RH, the capsules show unchanged hardness, chromatographic profiles and antioxidant activity compared to T0. Preclinical studies in monkeys showed that bioavailability was increased by a factor of 10 compared to marketed capsules comprising EGCG powder. This pharmaceutical development was conducted in the context of upcoming clinical trials to evaluate EGCG alone or in combination when treating transthyretin and light-chain cardiac amyloidosis.

Antioxidant and Neuroprotective Effects of the First Tryptophyllin Found in Snake Venom (Bothrops moojeni)

In this study, we report the isolation, characterization, and synthesis of the peptide BmT-2 belonging to the tryptophyllins family, isolated from the venom of the snake Bothrops moojeni. This is the first time a tryptophyllin is identified in snake venom. We tested whether BmT-2 had cytotoxic effects and antioxidant activity in a set of experiments that included both in vitro and cell-based assays. BmT-2 presented a radical scavenging activity toward ABTS^• and AAPH-derived radicals. BmT-2 protected fluorescein, DNA molecules, and human red blood cells (RBCs) from free radicals generated by the thermal decomposition of AAPH. The novel tryptophyllin was not toxic in cell viability tests, where it (up to 0.4 mg/mL) did not cause hemolysis of human RBCs and did not cause significant loss of cell viability, showing a CC₅₀ > 1.5 mM for cytotoxic effects against SK-N-BE(2) neuroblastoma cells. BmT-2 prevented the arsenite-induced upregulation of Nrf2 in Neuro-2a neuroblasts and the phorbol myristate acetate-induced overgeneration of reactive oxygen species and reactive nitrogen species in SK-N-BE(2) neuroblastoma cells. Electronic structure calculations and full atomistic reactive molecular dynamics simulations revealed the relevant contribution of aromatic residues in BmT-2 to its antioxidant properties. Our study presents a novel peptide classified into the family of the tryptophyllins, which has been reported exclusively in amphibians. Despite the promising results on its antioxidant activity and low cytotoxicity, the mechanisms of action of BmT-2 still need to be further elucidated.

Fruit Wine Obtained from Melon by-Products: Physico-Chemical and Sensory Analysis, and Characterization of Key Aromas by GC-MS

About 20% of fresh fruits and vegetables are rejected for not meeting the superficial aesthetic standards (color, shape, and size). Part of the food production is not used in the human food chain. The transformation of these fresh products into novel re-valuable ones is a challenge for a sustainable food industry. This research studies an alcoholic fermentation fruit-based wine from two melon (Cucumis melo L.) cultivars: Jimbee® (smooth and yellow skin with orange flesh) and Okashi® (netted yellow-orange skin with pale green flesh). The melon juice (must) was fermented by Saccharomyces cerevisiae and enriched in sucrose and organic acids to achieve alcoholic fermentation, acidity, and flavors, obtaining a fruity-flavored and dry melon-based wine with 10° alcoholic grade, in both melon cultivars. The volatile compounds were measured by GC-MS and the odor activity value (OAV) was calculated. The Jimbee and Okashi melon wines increased their aromatic profile due to an increment in medium-chain fatty acid ethyl esters such as ethyl hexanoate, ethyl octanoate, and ethyl decanoate (OAV > 1), which contributed to the fruity aroma. Other volatile compounds such as ethyl 9-decenoate and phenethyl acetate (OAV > 1) appeared in the Okashi wine, which brought a floral aroma. For sensory evaluation (40−100), the Jimbee cultivar, with its orange flesh, scored 68.2 and the Okashi cultivar, with pale green flesh, scored 82.8, which was the preferred melon-based wine. This is an example of a circular economy model to produce a fruit-based wine with commercial potential and satisfactory sensory evaluation.

Revitalizing Unfermented Cabernet Sauvignon Pomace Using an Eco-Friendly, Two-Stage Countercurrent Process: Role of pH on the Extractability of Bioactive Phenolics

As the major byproduct of the winemaking industry, grape pomace remains an untapped source of valuable bioactive phenolic compounds. This study elucidated the optimal aqueous extraction parameters for maximizing phenolic extractability, while avoiding the use of harsh conventional solvents and limiting water usage, from Cabernet Sauvignon grape pomace in which the red grape was processed for white wine. In the single-stage aqueous extraction process (AEP), the concurrent impact of pH (2.64–9.36), solids-to-liquid ratio (SLR, g pomace/mL water) (1:50–1:5), and temperature (41.6–58.4 °C) on the total phenolic content (TPC) of Cabernet Sauvignon pomace was evaluated alongside a kinetic study (15–90 min). Optimal single-stage extraction conditions (pH 9.36, 1:50 SLR, 50 °C, 75 min) guided the development of a two-stage countercurrent extraction process (pH 9.36, 1:10 SLR, 50 °C, 75 min) to further reduce water consumption without compromising overall extractability. The countercurrent process reduced fresh water usage by 80%, increased the TPC of the extracts by 18%, and improved the in vitro antioxidant activities (ABTS and ORAC) of the extracts. Untargeted metabolomics enabled the identification of a diverse pool of phenolics, especially flavonol glycosides, associated with grape pomace, while further phenolic quantitation detected improvements in the release of commonly bound phenolics such as ferulic acid, p-coumaric acid, syringic acid, and protocatechuic acid in alkaline extracts compared to the ethanolic extract. This investigation provides an efficient, eco-friendly extraction strategy suitable for applications in functional food, beverage, nutraceutical, and cosmetic industries.

Bioactive Compounds and In Vitro Antioxidant Capacity of Cambuci and Uvaia: An Extensive Description of Little-Known Fruits from the Myrtaceae Family with High Consumption Potential

Cambuci (Campomanesia phaea O. Berg Landrum) and uvaia (Eugenia pyriformis Cambess), both native Atlantic Rainforest fruits, are noteworthy for being rich in bioactive compounds and their significant antioxidant capacity. Despite the numerous known edible fruits in the world, consumption by humans is most often restricted to a few dozen of them. Such behavior occurs, among other reasons, due to the lack of knowledge about fruits not yet commercialized on a large scale. This study quantified the bioactive compound content (total phenolic compounds and ascorbic acid in cambucis and uvaias; proanthocyanidins in cambucis, and total carotenoid profile and individual carotenoids for grapes) and antioxidant capacity of the edible parts (peel and pulp) of cambuci and uvaia accessions, using three methods (ABTS•+, ROO• radical scavenging and HOCl elimination). Cambuci contained higher phenolic compound levels and displayed higher antioxidant capacity determined by the ABTS•+ and ROO• radical scavenging methods than uvaia (139 and 119 mg 100 g⁻¹ of GAE, 10.5 and 7.73 μmol g⁻¹ of TE; 9.17 and 5.92 μmol g⁻¹ of TE, respectively). Vitamin C content and the antioxidant capacity determined by the HOCl elimination method were about 1.5- and 6-fold higher in uvaia compared to cambuci, with the latter being a first-time report for uvaia. Both fruits contained higher levels of bioactive compounds and antioxidant capacity than other commonly consumed fruits.

Membrane Technology for Valorization of Mango Peel Extracts

Mango peel is rich in nutritional and functional compounds, such as carbohydrates, dietary fibers, proteins, and phenolic compounds, with high potential to be applied in the food industry. Most of the investigation about recovery of bioactive compounds from fruit bioproducts involves extraction techniques and further separation of target compounds. There is still a lack of information about the potential of membrane processes to recover the nutritive/functional compounds present in aqueous extracts of those bioproducts. This research is addressed to study the performance of ultrafiltration (UF), followed by nanofiltration (NF) of UF permeates, to fractionate the compounds present in aqueous extracts of mango peel. Both UF and NF concentration processes were carried up to a volume concentration factor of 2.0. Membranes with molecular weight cut-offs of 25 kDa and 130 Da were used in the UF and NF steps, respectively. UF and NF concentrates showed antioxidant activity, attributed to the presence of phenolic compounds, with rejections of about 75% and 98.8%, respectively. UF membranes totally rejected the higher molecular weight compounds, and NF membranes almost totally concentrated the fermentable monosaccharides and disaccharides. Therefore, it is envisaged that NF concentrates can be utilized by the food industry or for bioenergy production.

Determination of the Bioactive Effect of Custard Apple By-Products by In Vitro Assays

Annona cherimola fruit, known as cherimoya or custard apple, is an exotic fruit from South America but is strongly produced in Andalusia, Spain. Its by-products (seeds and peel) are recognised as important sources of antioxidants, including phenolic acids, flavonoids and procyanidins. Therefore, the aim of this study was to carry out the characterization of its phenolic composition and to in vitro evaluate the bioactivity of custard apple seed and peel. Therefore, high performance liquid chromatography coupled to mass spectrometry (HPLC-ESI-qTOF-MS) was performed in order to tentatively identify their phenolic composition. In the end, 19 compounds were identified and quantified, some of them for the first time in the custard apple matrix. Then, seed and peel total phenolic content, as well as antioxidant properties, radical scavenging capacity (O₂, NO, HOCl) and inhibition of enzymes involved in different pathologies (hyaluronidase, elastase, collagenase, tyrosinase, acetylcholinesterase and xanthine oxidase), were evaluated. Although both extracts showed almost similar antioxidant capacities, custard apple seed stood out slightly more than peel (171 ± 2 vs. 130.0 ± 0.4 μmol TE/g DE, resp.), especially as ·NO scavenger (IC₅₀ 1.5 ± 0.2 vs. 11.8 ± 0.3 mg/L, resp.) and hyaluronidase inhibitor (IC₅₀ 170 ± 10 vs. 460 ± 20mg/L, resp.). Finally, the application of extracts on a real human model of platelet aggregation was performed, reporting antiaggregatory effects in agonist-promoted platelet thrombus formation. All these results show that custard apple by-products are stated as interesting sources of bioactive compounds with multiple industrial applications for the development of high-added-value products, such as functional foods, nutraceuticals and cosmeceuticals, promoting the circular bioeconomy of these by-products.

Changes in Phenolic Compound and Antioxidant Activity of Germinated Broccoli, Wheat, and Lentils during Simulated Gastrointestinal Digestion

The consumption of sprouts has increased as the germination process causes changes in the chemical composition of the seeds, improving their nutritional value. The aim of this work was to compare the total phenolic content and antioxidant capacity of broccoli, lentils and wheat sprouts before and after in vitro digestion, and the total phenolic content and antioxidant capacity between seeds and sprouts. Broccoli and wheat showed no difference in total phenolic content before and after germination, while lentils showed a significant decrease in total phenolic content after germination. The antioxidant capacity of broccoli and wheat increased after germination. After simulated digestion, the total phenolic content and antioxidant activity of broccoli sprouts significantly decreased during digestion in the gastric phase compared to the sprouts before digestion. Lentil sprouts did not show a decrease in total phenolic content during the gastric phase of digestion compared to the sprouts before digestion. However, they showed a significant increase in total phenolic content during the enteric phase. Finally, wheat sprouts showed a significant increase in total phenolic content and antioxidant activity during the gastric phase of digestion compared to grain before digestion. The germination process may increase the antioxidant capacity of sprouts, although this is not always related to the phenolic compound.

Evaluation of antidiabetic, antioxidant and antilipidemic potential of natural dietary product prepared from Cyphostemma digitatum in rats’ model of diabetes

Introduction: Cyphostemma digitatum has a high content of antioxidant constituents and has been employed by the traditional healers and local people of Yemen for diabetes treatment. However, scientific evidence regarding its antidiabetic efficacy is largely unknown. Accordingly, the present study aimed to confirm the treatment effects of a dietary natural product prepared from Cyphostemma digitatum (PCD) in diabetic rats.Methods: Diabetes was induced by a high-fat diet and streptozotocin (HF-STZ). PCD (1 g/kg) was given by gavage administration once a day continuously for 30 days. At the end of treatment, blood and skeletal muscle samples were collected for further analysis.Results: The antidiabetic effects of PCD were demonstrated by significant reduction (P ≤ 0.05) in the levels of serum glucose (40%), triglyceride (32%), cholesterol (53%), low-density lipoprotein (LDL) (44%), malondialdehyde (MDA) (61%) in PCD treated groups compared to the diabetic control group. Additionally, PCD treatment significantly (P ≤ 0.05) restored the decreased levels of insulin (70%) and the activities of superoxide dismutase (SOD) (57%) and reduced glutathione (GSH) (544%) when compared to that of diabetic control rats. We found that treatment with PCD for 30 days fully restored the plasmalemmal glucose transporter type 4 (GLUT4) contents, as well as the phosphorylation of phosphatidylinositol 3-kinase (PI3K) (P ≤ 0.05).Conclusion: Thus, PCD treatment can be considered a potential drug candidate for diabetes.

Anticancer effects of root and beet leaf extracts (Beta vulgaris L.) in cervical cancer cells (HeLa)

Cervical cancer is the fourth leading cause of cancer mortality in women worldwide. Beetroot (Beta vulgaris L.) has bioactive compounds that can inhibit the progression of different types of cancer. To analyze the antiproliferative effects of beet leaf and root extracts, we performed MTT, clonogenic survival, cell cycle analysis, Annexin/PI labeling, and western blotting. Here, we report that 10 and 100 μg/ml of root and leaf extracts decreased cell viability and potentiated rapamycin and cisplatin effects while decreased the number of large colonies, especially at 10 μg/ml (293.6 of control vs. 200.0 of leaf extract, p = .0059; 138.6 of root extract, p = .0002). After 48 hr, 100 μg/ml of both extracts led to increased sub-G1 and G0/G1 populations. In accordance, 100 μg/ml of root extract induced early apoptosis (mean = 0.64 control vs. 1.56 root; p = .048) and decreased cell size (p < .0001). Both extracts decreased phosphorylation and expression of mechanistic Target of Rapamycin (mTOR) signaling, especially by inhibiting ribosomal protein S6 (S6) phosphorylation, increasing cleaved poly(ADP-ribose) polysomerase 1 (PARP1) and Bcl-2-like protein 11 (BIM), and decreasing cyclin D1 expression, which regulates cell cycle progression. Here, we demonstrate that beetroot and leaf extracts could be an efficient strategy against cervical cancer.

Exploiting the chemical composition of essential oils from Psidium cattleianum and Psidium guajava and its antimicrobial and antioxidant properties

The genus Psidium comprises several native Brazilian plants, such as the araçá and guava trees. They are interesting sources of essential oils (EOs) that can be used as natural preservatives in foods due to their bioactive properties. This work aimed to evaluate and correlate the biological properties of the EOs from araçá and guava leaves with their chemical compounds. The gas chromatography-mass spectrometry (GC/MS) was used to determine the chemical composition of EOs. The antimicrobial activity was tested against 16 foodborne pathogens and the antioxidant capacity was determined by ABTS, DPPH, and FRAP assays. The major compounds identified in the essential oil of araçá (EOA) were β-caryophyllene and β-elemene, representing 38.69% and 7.47%, respectively, whereas β-selinene (13.83%), α-humulene (10.90%), and β-caryophyllene (7.61%) were the major compounds identified in the essential oil of guava (EOG). Both EOs showed activity against Salmonella Enteritidis, with MIC being 1.41 µg/ml for the EOA and 1.37 µg/ml for the EOG. The EOA was more effective than the EOG against strains of Listeria monocytogenes and Pseudomonas aeruginosa, with the MIC being 1.41 µg/ml. The EOA showed 10.43, 12.35, and 3.92 µmol TE/ml at 90 µg/ml whereas the EOG showed 4.54, 8.94, and 3.43 µmol TE/ml at 88 µg/ml for ABTS, DPPH, and FRAP, respectively. Thus, the EOs demonstrated an effective action against foodborne pathogens and free radicals, indicative of their potential use as natural preservatives for foods. PRACTICAL APPLICATION: Guava and araçá are native Brazilian plants producers of essential oils, natural compounds with antimicrobial and antioxidant potential. The chemical composition of essential oils is responsible for its beneficial properties. The results demonstrated that the essential oils studied are rich in β-caryophyllene and has excellent activity against malefic microorganisms and free radicals, and can also be used as natural preservatives in foods.

Essential Oils Extracted from Organic Propolis Residues: An Exploratory Analysis of Their Antibacterial and Antioxidant Properties and Volatile Profile

The industrial processing of crude propolis generates residues. Essential oils (EOs) from propolis residues could be a potential source of natural bioactive compounds to replace antibiotics and synthetic antioxidants in pig production. In this study, we determined the antibacterial/antioxidant activity of EOs from crude organic propolis (EOP) and from propolis residues, moist residue (EOMR), and dried residue (EODR), and further elucidated their chemical composition. The EOs were extracted by hydrodistillation, and their volatile profile was tentatively identified by GC-MS. All EOs had an antibacterial effect on Escherichia coli and Lactobacillus plantarum as they caused disturbances on the growth kinetics of both bacteria. However, EODR had more selective antibacterial activity, as it caused a higher reduction in the maximal culture density (D) of E. coli (86.7%) than L. plantarum (46.9%). EODR exhibited mild antioxidant activity, whereas EOMR showed the highest antioxidant activity (ABTS = 0.90 μmol TE/mg, FRAP = 463.97 μmol Fe²⁺/mg) and phenolic content (58.41 mg GAE/g). Each EO had a different chemical composition, but α-pinene and β-pinene were the major compounds detected in the samples. Interestingly, specific minor compounds were detected in a higher relative amount in EOMR and EODR as compared to EOP. Therefore, these minor compounds are most likely responsible for the biological properties of EODR and EOMR. Collectively, our findings suggest that the EOs from propolis residues could be resourcefully used as natural antibacterial/antioxidant additives in pig production.

Beetroot and leaf extracts present protective effects against prostate cancer cells, inhibiting cell proliferation, migration, and growth signaling pathways

Beet (Beta vulgaris L.) has high nutritional value, containing bioactive compounds such as betalains and flavonoids. Scientific evidence points to the use of these natural compounds in the treatment of several types of cancer, such as prostate cancer, one of the main causes of morbidity and mortality in men. Here, we compared beet roots and leaves extracts, and their main compounds, apigenin, and betanin, respectively, in DU-145 and PC-3 prostate cancer cell lines. Both cells presented the proliferation decreased for beetroot and beet leaves extracts. The apigenin treatment also reduced the proliferation of both cell lines. Regarding cell migration, beet leaves extract was able to decrease the scratch area in both cell lines, whereas apigenin affected only PC-3 cells' migration. In colony formation assay, both extracts were effective in reducing the number of colonies formed. Besides, the beet leaves extracts and apigenin presented strong inhibition of growth-related signaling pathways in both cell lines, and the beetroot extract and betanin presented effects only in DU-145 cells. Furthermore, the extracts and isolated compounds were able to reduce the levels of apoptotic and cell cycle proteins. This study reveals that beet extracts have important anti-cancer effects against prostate cancer cells.

Active Antioxidant Phenolics from Brazilian Red Propolis: An Optimization Study for Their Recovery and Identification by LC-ESI-QTOF-MS/MS

Brazilian red propolis (BRP) is a natural product widely known for its phenolic composition and strong antioxidant properties. In this study, we used the Box–Behnken Design (BBD) with Surface Response Methodology to optimize the extraction conditions for total phenolic content (TPC) and Trolox equivalent antioxidant capacity(TEAC) of bioactive phenolics from BRP. The extraction time, ethanol/water concentration and temperature, were tested. All variables had significant effects (p  ≤ 0.05), with a desirability coefficient of 0.88. Under optimized conditions (90% ethanol at 80 °C for 30 min), the BRP extract showed a TPC of 129.00 ± 2.16 mg GAE/g and a TEAC of 3471.76 ± 53.86 µmol TE/g. Moreover, FRAP and ORAC assays revealed that the optimized BRP extract had 1472.86 ± 72.37 µmol Fe²⁺/g and 4339.61 ± 114.65 µmol TE/gof dry weight, respectively. Thirty-two phenolic compounds were tentatively identified by LC-QTOF-ESI-MS/MS, of which thirteen were found for the first time in BRP, including four flavones, one flavanol, two flavanones, two chalcones, and four isoflavonoids. Thus, our results highlight the importance of BRP as a source of a wide variety of phenolic compounds with significant antioxidant properties.

Bioaccessibility of cashew nut kernel flour compounds released after simulated in vitro human gastrointestinal digestion

Cashew nuts are mainly consumed as a roasted and salted snack. Lately, the industry has gained interest in broken kernels because of their added value. In this study, defatted cashew nut flour (DCF) underwent simulated gastrointestinal digestion to obtain a soluble (CDs) and an insoluble (CDi) digested fraction. These fractions, which resulted from the digestion of a complex matrix, were evaluated for antioxidant capacity of bioaccessible compounds (present on the soluble digested fraction, CDs) and their potential prebiotic effect, considering that the insoluble digested fraction (CDi) could be fermented by the microbiota in the gut. The DCF had a high protein content (40.74%), being nutritionally characterized as a balanced source of amino acids, with a predominance of aromatic amino acids (phenylalanine and tyrosine), threonine and histidine. The digested DCF presented 76.90% of the soluble components of low molecular weight (0.1-2 kDa), which is typical of antioxidant peptides. The soluble digested fraction (CDs) significantly increased the antioxidant capacity in relation to flour in the ORAC and ABTS assays and the aqueous extract presented the highest values (526.0 and 76.64 as µmol Trolox Eq./g sample, respectively). The CDs protected 29.03% of the supercoiled DNA band and ratified the potential antioxidant capacity after GID in a physiological assay. In addition, the insoluble digested fraction showed a potential prebiotic effect for Bifdobacterium lactis BB-12. Finally, simulated gastrointestinal digestion improves the bioaccessibility of CDF antioxidant compounds as a complex matrix, containing low molecular weight peptides and phenolic compounds, which become more available to react with reactive oxygen species (ROS). In addition, the potential prebiotic effect of defatted cashew nut flour has yielded a promising solution for the total reuse of broken cashew nut kernel as a functional food ingredient.

Effects of convective drying assisted by ultrasound and osmotic solution on polyphenol, antioxidant and microstructure of murtilla (Ugni molinae Turcz) fruit

The effects of pretreatment with ultrasound and an osmotic solution combined with hot air convection drying on the total polyphenol content (TPC), antioxidant activity and microstructural of murtilla skin fruit were evaluated. The effects of ultrasound frequency (0 and 130 kHz), osmotic solution concentration (0 and 70 °Brix) and time (60 or 120 min) on the TPC and the antioxidant activities as measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC) assays were evaluated. The TPC and DPPH antioxidant activity decreased significantly (p < 0.05) when ultrasound was applied at 0 °Brix for 60 min. Higher FRAP activity was obtained upon treatment with ultrasound and an osmotic solution for 60 min. The ORAC values did not significantly differ based on the pretreatment methods but decreased when an osmotic solution was applied for 120 min without ultrasound. When ultrasound and the osmotic solution were applied, the skin cells of the dried murtilla fruit became more distorted, resulting in larger spaces between them and causing loss of shape. Although the application of pretreatment procedures before murtilla fruit drying did not positively affect the TPC, DPPH or ORAC individually, the application of a Global Standardized Response based on the followed by a mathematical model adjustment indicated that a 70 °Brix osmotic solution applied for 60 min was the best treatment for preparing murtilla fruit aiming a high antioxidant activity in dried product.

Physicochemical, nutritional, bioactive compounds and fatty acid profiling of Pumpkin flower (Cucurbita maxima), as a potential functional food

The edible flowers and its several products gaining its importance as functional food. Pumpkin flower mainly consumed in India and Mexico but due to lack of scientific research there is a neophobia among people. The objective of the paper is to analyse the physicochemical, biochemical properties, proximate analysis, antioxidant activities, anthocyanin content and fatty acid profiling. The fresh pumpkin flower was having an average moisture content of 85% (wb) with a dimension of 90 × 51 x 22 mm (l x w x t). The (L, a*, b*) value signifies the bright yellow color having gumminess (26 g) and chewiness (4.70 mJ). In this study the nutritional properties of the pumpkin flower were also determined and significant amount of Sodium (11.5 mg/100 g), Potassium (18.2 mg/100 g), Calcium (17.6 mg/100 g), phenol (17.39 µg/ml), flavonoid (17.13 µg/ml), antioxidant (51.65%DPPH) and anthocyanin (10.3 mg/100 g) was present. Among several fatty acids’ oleic acid (21%), myristic acid (15.99%) and stearic acid (15.19%) was maximum. The presence of several phytonutrients and fatty acids makes pumpkin flower a potential source of functional food in near future.

Graphical abstract

Isolation and Sequencing of Cu-, Fe-, and Zn-Binding Whey Peptides for Potential Neuroprotective Applications as Multitargeted Compounds

This study aims to isolate metal-binding peptides and synthesize promising amino acid sequences to potentially act as neuroprotective compounds in the future, targeting different mechanisms. Fractions of whey metal-binding peptides (Cu, Fe, and Zn) isolated by immobilized metal affinity chromatography showed different amino acid profiles according to the metal. The Cu-binding peptides presented roughly twofold increase in the in vitro antioxidant, as assessed by oxygen radical absorbance capacity and anticholinesterase activities over the hydrolysate. This is probably because of the higher concentration of aromatic and basic residues, the latter being crucial for binding to the anionic sites of acetylcholinesterase. Six peptide sequences were synthesized based on the metal-binding sites, molecular mass, hydrophobicity, and bioactivity probability. Among the synthetic peptides, the VF dipeptide stood out both for its in vitro antioxidant and anticholinesterase activities. This peptide, as well as the fraction of Cu-binding peptides, should be further studied because it may act through different mechanisms related to neurodegenerative diseases, in addition to the chelation of the excess of metals in the central nervous system.

Free and insoluble-bound phenolics: How does the variation of these compounds affect the antioxidant properties of mustard grains during germination?

This work aimed to investigate how the variation of free and insoluble-bound phenolics affected the antioxidant properties of mustard grains from two varieties (black - Brassica nigra and white - Sinapsis alba) during different germination parameters. The germination conditions selected for each mustard variety to improve their antioxidant properties were different, as follows: (a) for white mustard - 72 h of germination at 25 °C in the dark and (b) for black mustard - 48 h of germination at 25 °C alternating dark and light periods. At these conditions, increases of 49, 72, 80, 68, 42, 66 and 45% were detected for total phenolic compounds (TPC), total flavonoids, condensed tannins, FRAP, DPPH, ABTS, and ORAC, respectively, for soluble extracts of white mustard compared to the non-germinated white mustard. The soluble extracts from black mustard, in turn, presented increases of 44, 18, 55, 29, 3, 160 and 42% for TPC, total flavonoids, condensed tannins, FRAP, DPPH, ABTS, and ORAC, respectively, compared to the non-germinated sample. Gallic acid, 3,4-di-hydroxybenzoic acid, sinapic acid, ferulic acid, coumaric acid, and rutin were identified by UPLC-MS/MS and were the main compounds detected in mustard extracts. Given the results obtained, germinated mustard grains have the potential for application as a functional and nutraceutical food.

Optimizing the antioxidant biocompound recovery from peach waste extraction assisted by ultrasounds or microwaves

The possibility to valorize peach juice waste, either frozen or air-dried, through microwave (MAE) and ultrasound assisted extraction (UAE) was evaluated. MAE power, UAE amplitude and time were optimized using a 2²-factorial design. For frozen waste, optimal MAE (540 W, 50 s) and UAE (23%, 120 s) processes gave extracts presenting analogous content (on 100 g dry matter) of polyphenols (309-317 mg GAE), flavonoids (94-120 mg QE), anthocyanins (8-9 mg CGE), and similar antioxidant activity (2.1-2.2 mg TE). Extracts from dried waste resulted higher in polyphenols (630-670 mg GAE) but lower in flavonoids (75-90 mg QE), anthocyanins and vitamin C (not detectable). Although developing an energy density 2-fold higher than that of UAE, MAE more efficaciously extracted vitamin C (108 mg/100 g dm) and required half extraction time (50 s). MAE would also be less impactful than UAE in terms of greenhouse gas emission and energy requirements on industrial scale. The industrial valorization of peach waste through the application of microwave or ultrasound assisted extraction requires quantitative data, able to encourage company interest and investment. This study not only identifies optimal MAE and UAE parameters to assist the extraction of peach waste bioactive compounds but also provides a preliminary estimation of the potential economic and environmental impact on an industrial scale of these technologies.

Dietary fibres from guavira pomace, a co-product from fruit pulp industry: Characterization and cellular antioxidant activity

Exotic fruits and their co-products may be valuable sources of antioxidant dietary fibres (DF) which are useful for food industry and human health. In this study, we aimed to characterize DF obtained from guavira fruit pomace and investigate its antioxidant potential employing TEAC assay as well as a cell model. The DF were chemically characterized as containing arabinan, highly-methoxylated homogalacturonan and arabinogalactan. The DF-containing fraction (CPW) presented ABTS free radical scavenger activity. MTT and DCFH-DA assay were performed to assess, respectively, changes in cell viability and the potential intracellular antioxidant activity against H₂O₂-induced oxidative stress in murine NIH 3T3 fibroblast. CPW exhibited no effects on cell viability, moreover, when administered 48 h prior the induction of H₂O₂ toxic effects, it protected the cells, significantly increasing the cell viability compared to control. This protection may be related to the observed reduction of reactive oxygen species levels. Thus, the pre-treatment of cells with guavira DF for 48 h remarkably induced a cytoprotection against pro-oxidant conditions, and may be a valuable functional compound recovered from an unexploited agroindutrial waste.

Polyphenols, Vitamin C, in Vitro Antioxidant Capacity, α-Amylase and COX-2 Inhibitory Activities of Citrus Samples from Aceh, Indonesia

Abstract. This study was conducted to analyse antioxidant potencies, vitamin C contents, polyphenol profiles, antidiabetic and anti-inflammatory potencies of citrus fruits from Indonesia. Total phenolics contents (TPC) of seven citrus fruits from northern Aceh, Indonesia, were measured using Folin-Ciocalteu (FC) and Fast Blue BB (FBBB) methods. Total flavonoid content (TFC) test showed for peel and pulp extracts of calung and jeruk takengon (local mandarin) the highest values. H-TEAC (hydrophilic trolox equivalent antioxidant capacity) and H-ORAC (hydrophilic oxygen reactive absorbance capacity) antioxidant capacity were highest for peel and pulp of jeruk takengon, calung and kruet mameh. Interestingly, peel extracts showed no α-amylase inhibition activity whilst pulp showed weak inhibitory activity. Polyphenol composition was dominated by flavanones, with hesperidin and neohesperidin as main flavanones (hesperidin: 131–5433 mg/100 g DW, neohesperidin: 431–4131 mg/100 g DW). Vitamin C contents were highly correlated with antioxidant capacities in pulp (R2 = 0.95 and R2 = 0.94 at p < 0.01 for H-TEAC and H-ORAC, respectively), and TPC and TFC were highly correlated with antioxidant capacities (R2 = 0.99 and R2 = 0.98 for TPC FC in pulp and R2 = 0.93 and R2 = 0.84 in peel for H-TEAC and H-ORAC, respectively; R2 = 0.88 and R2 = 0.80 in pulp, and R2 = 0.68 and R2 = 0.75 for TFC in peel for H-TEAC and H-ORAC at p < 0.01). In-vitro COX-2 inhibitory activity tests resulted in higher activity for pulp compared to the corresponding peel extracts except for calung. Pulp extract of jeruk takengon showed the highest activity. In general, local citrus fruits from Aceh, Indonesia, are potential sources of polyphenols and vitamin C.

Use of Agaricus bisporus mushroom in beef burgers: antioxidant, flavor enhancer and fat replacing potential

Abstract

This study aimed to evaluate the potential use of Agaricus bisporus mushroom as a natural antioxidant, fat/salt substitute and flavor enhancer in beef burger. Ten treatments were considered using a fractional factorial design (salt [0.5, 1.25 and 2.0%], fat [10, 15 and 20%] and mushroom content [0, 15 and 30%]). Treatments were characterized by instrumental and sensory measurements. The statistical design indicated that fat content had little influence on the results. The principal component analysis showed that the incorporation of mushrooms and salt modified the texture, moisture and water activity. Oxidative stability decreased as the salt content increased, at a low-fat content. Finally, the sensory profile was affected by the mushroom and salt contents, with the fat content exerting the least influence. Therefore, mushroom incorporation in beef burger may be a feasible strategy to reduce the fat content of beef burgers.

Graphical abstract

Solvent polarity mediates phytochemical yield and antioxidant capacity of Isatis tinctoria

Secondary metabolites have been extensively used in the treatment of various health problems. The role of solvent polarity on the phytochemical isolation and antioxidant capacity of Isatis tinctoria (woad) is elusive. In the present study, 14 solvents with different polarity were used in the extraction and total phenolic and flavonoid content (TPC and TFC) investigation. Ferricyanide, phosphomolybdenum, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) methods were used to calculate and compare the antioxidant/free radical scavenging capacity. Our results showed that solvent polarity greatly affects TPC and TFC yield, which is mainly increasing with increasing solvent polarity index and suddenly decreasing at very high polarity. The comparative results showed that TPC is directly correlated with reducing power, antioxidant, and free radical scavenging capacity. Taken together, we conclude that different woad plant parts contain different level of secondary metabolites with a specific polarity that requires a particular solvent with an appropriate polarity index for the extraction. The identification of these biologically active crude extracts and fractions are very important for the basic biological sciences, pharmaceutical applications, and future research for HPLC based active compounds isolation.

Solid-state fermentation as an efficient strategy for the biotransformation of lentils: enhancing their antioxidant and antidiabetic potentials

Background

Fermentation is a classic industrial process that can be applied as an efficient strategy to increase the release of bioactive compounds with antioxidant and antidiabetic activities.

Methods

This work reported the effects of solid-state fermentation (SSF) performed using strains of Aspergillus oryzae and Aspergillus niger on the antioxidant (DPPH, ABTS and FRAP) and in vitro antidiabetic (inhibition of α-amylase and α-glucosidase activities) potential of lentils.

Results

The results showed that the profiles of the biological activities of the extracts obtained from the fermented samples varied greatly with respect to both the microorganism involved and the fermentation time. The extracts obtained from the fermented lentils by A. oryzae after 72 h and by A. niger after 48 h using the FRAP assay showed the most remarkable changes in the antioxidant activity, increasing by 107 and 81%, respectively, compared to the nonfermented lentils. The lentil extracts produced by fermentation with A. niger after 48 h were able to inhibit the α-glucosidase activity by up to 90%, while a maximal inhibition of amylase (~ 75%) was achieved by the lentil extract obtained after 24 h of fermentation with A. oryzae. The content of the total phenolic compounds (TPCs) and the identification of them in lentil extracts correlated well with the improvement of the biological activities.

Conclusion

These results suggested that SSF was feasible to obtain extracts of fermented lentils with improved antioxidant and antidiabetic properties. Additionally, these results indicated that the proper choice of microorganism is crucial to direct the process for the production of compounds with specific biological activities.