Exploring the phenolic profile, antioxidant, antidiabetic and anti-hemolytic potential of Prunus avium vegetal parts

Antioxidant, Phytochemical, and Pharmacological Properties of Algerian Mentha aquatica Extracts

Water mint (Mentha aquatica) is used in many formulations worldwide as a functional food and natural remedy to treat gastrointestinal disorders, lung diseases, and certain mental disorders such as epilepsy and depression. This study assessed the bioactivity of its infusion extract (INF) and hydroethanolic extract (HE) to highlight its health benefits. These extracts were analyzed for their chemical composition by HPLC-DAD-ESI-MSn, their antioxidant and antidiabetic properties, and their capacities to protect human erythrocytes against induced hemoglobin oxidation and lipid peroxidation. The effect on normal human dermal fibroblast (NHDF) cells and on the N27 rat dopaminergic neuron cell line was also assessed. The chromatographic analysis identified 57 compounds belonging to hydroxycinnamic acids, flavanones, flavone, and isoflavonoids. In respect to the biological potential, the Mentha aquatica extracts revealed a notable capacity for 2,2-diphenyl-1-picrylhydrazyl, nitric oxide, and superoxide radicals, as well as for the inhibition of α-glucosidase action and the protection of human erythrocytes against oxidative damage. Quantification revealed noteworthy phenolic content in both extracts. Additionally, the extracts demonstrated less cytotoxic effects regarding the NHDF and N27 cell lines. Overall, Mentha aquatica presents promising antioxidant activity and a spectrum of potential biological activities, underscoring its significance as a novel antioxidant candidate for applications in animal nutrition, human medicine, and natural product research in the pharmaceutical and nutraceutical industries.

Potential Role of Dietary Phenolic Compounds in the Prevention and Treatment of Rheumatoid Arthritis: Current Reports

Rheumatoid arthritis (RA) is a complex illness with both hereditary and environmental components. Globally, in 2019, 18 million people had RA. RA is characterized by persistent inflammation of the synovial membrane that lines the joints, cartilage loss, and bone erosion. Phenolic molecules are the most prevalent secondary metabolites in plants, with a diverse spectrum of biological actions that benefit functional meals and nutraceuticals. These compounds have received a lot of attention recently because they have antioxidant, anti-inflammatory, immunomodulatory, and anti-rheumatoid activity by modulating tumor necrosis factor, mitogen-activated protein kinase, nuclear factor kappa-light-chain-enhancer of activated B cells, and c-Jun N-terminal kinases, as well as other preventative properties. This article discusses dietary polyphenols, their pharmacological properties, and innovative delivery technologies for the treatment of RA, with a focus on their possible biological activities. Nonetheless, commercialization of polyphenols may be achievable only after confirming their safety profile and completing successful clinical trials.

Variability in the Qualitative and Quantitative Composition of Phenolic Compounds and the In Vitro Antioxidant Activity of Sour Cherry (Prunus cerasus L.) Leaves

Sour cherry (Prunus cerasus L.) is a deciduous tree belonging to the Rosaceae Juss. family. Cherry leaves are an underutilized source of biologically active compounds. The aim of this study was to determine the composition of the phenolic compounds, as well as the total antioxidant activity, in leaf samples of P. cerasus cultivars and to elucidate the cultivars with particular phytochemical compositions. The phytochemical profiles of P. cerasus leaves vary significantly in a cultivar-dependent manner. The total content of identified phenolic compounds varied from 8.254 to 16.199 mg/g in the cherry leaves. Chlorogenic acid ranged between 1413.3 µg/g ('North Star') and 8028.0 µg/g ('Note'). The total content of flavonols varied from 4172.5 µg/g ('Vytenu zvaigzde') to 9030.7 µg/g ('Tikhonovskaya'). The total content of identified proanthocyanidins varied from 122.3 µg/g ('Note') to 684.8 µg/g ('Kelleris'). The highest levels of phloridzin (38.1 ± 0.9 µg/g) were found in samples of 'Molodezhnaya', while the lowest level of this compound was determined in the leaf samples of 'Turgenevka' (6.7 ± 0.2). The strongest antiradical (138.0 ± 4.0 µmol TE/g, p < 0.05) and reducing (364.9 ± 10.5 µmol TE/g, p < 0.05) activity in vitro was exhibited by the cultivar 'Vytenu zvaigzde' cherry leaf sample extracts. 'Kelleris', 'Note', and 'Tikhonovskaya' distinguish themselves with peculiar phytochemical compositions.

Macroporous resin purification of phenolics from Irish apple pomace: Chemical characterization, and cellular antioxidant and anti-inflammatory activities

Apple pomace (AP) is a highly prevalent waste product worldwide in the fruit processing sector. This study compared the chemical profile, antioxidant, and anti-inflammatory activities of crude (CE) and an extract purified using XAD-7 resin (PE). The purification process increased the total phenolic content, flavonoids, and tannins by 3.35, 40.31, and 8.87-fold, respectively. The main phenolic compounds identified in PE were phlorizin (20.54 mg/g), chlorogenic acid (10.01 mg/g), and hyperoside (2.77 mg/g). No difference was found between CE and PE in protecting human plasma against oxidation. In human erythrocytes, both CE and PE decreased the reactive oxygen species (ROS) generation and decreased lipoperoxidation. However, PE had stronger anti-inflammatory effects than CE by promoting HO-1 gene expression, suppressing NO production, and inhibiting IL-1β, IL-6, and IL-10 mRNA expression in lipopolysaccharide-challenged RAW.264.7 macrophages. Therefore, purifying apple pomace crude extract is a promising approach to boosting valuable antioxidants and anti-inflammatory phenolics.

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.

Differential response of blueberry to the application of bacterial inoculants to improve yield, organoleptic qualities and concentration of bioactive compounds

The application of bacterial biofortifiers is an increasingly common technique. In recent years, some strains have been shown to improve the nutraceutical qualities of crops. This work analyses the impact of biofortification with 3 bacterial strains of the genera Rhizobium, Paenibacillus and Lactiplantibacillus on the nutritional characteristics and organic composition of blueberry in Portugal. Paenibacillus sp. VMFR46 treatment showed increase of 71.36 % and 79.88 % in total production. Biofortified treatments were able to increase Brix degree, maturity index (up to 48.05 % for cv. Legacy and up to 26.04 % for cv. Duke) and CIEL*a*b* index respect to uninoculated control. In this way, (poly)phenolic compounds concentration increased in biofortified treatment, and their (poly)phenolic profile was modified, some compounds such as myricetin aglycone or myricetin derivative are exclusive of the fruits from biofortified plants, with increases in (poly)phenolic concentrations related with R. laguerreae PEPV16 or Paenibacillus sp. VMFR46 inoculation in cv. Legacy. These modifications resulted in the improvement of the nutraceutical characteristics of the fruits obtained.

A Prunus avium L. Infusion Inhibits Sugar Uptake and Counteracts Oxidative Stress-Induced Stimulation of Glucose Uptake by Intestinal Epithelial (Caco-2) Cells

Sweet cherry (Prunus avium L.) is among the most valued fruits due to its organoleptic properties and nutritional worth. Cherry stems are rich in bioactive compounds, known for their anti-inflammatory and antioxidant properties. Innumerable studies have indicated that some bioactive compounds can modulate sugar absorption in the small intestine. In this study, the phenolic profile of a cherry stem infusion was investigated, as well as its capacity to modulate intestinal glucose and fructose transport in Caco-2 cells. Long-term (24 h) exposure to cherry stem infusion (25%, v/v) significantly reduced glucose (3H-DG) and fructose (14C-FRU) apical uptake, reduced the apical-to-basolateral Papp to 3H-DG, and decreased mRNA expression levels of the sugar transporters SGLT1, GLUT2 and GLUT5. Oxidative stress (induced by tert-butyl hydroperoxide) caused an increase in 3H-DG uptake, which was abolished by the cherry stem infusion. These findings suggest that cherry stem infusion can reduce the intestinal absorption of both glucose and fructose by decreasing the gene expression of their membrane transporters. Moreover, this infusion also appears to be able to counteract the stimulatory effect of oxidative stress upon glucose intestinal uptake. Therefore, it can be a potentially useful compound for controlling hyperglycemia, especially in the presence of increased intestinal oxidative stress levels.

The Chemical Profile, Antioxidant, and Anti-Lipid Droplet Activity of Fluid Extracts from Romanian Cultivars of Haskap Berries, Bitter Cherries, and Red Grape Pomace for the Management of Liver Steatosis

This study aimed to investigate, for the first time, the chemical composition and antioxidant activity of fluid extracts obtained from three Romanian cultivars of haskap berries (Lonicera caerulea L.) var. Loni, bitter cherries (Prunus avium var. sylvestris Ser.) var. Silva, and pomace from red grapes (Vitis vinifera L.) var. Mamaia, and their capacity to modulate in vitro steatosis, in view of developing novel anti-obesity products. Total phenolic, flavonoid, anthocyanin, and ascorbic acid content of fluid extracts was spectrophotometrically assessed and their free radical scavenging capacity was evaluated using Trolox Equivalent Antioxidant Capacity (TEAC) and free 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical inhibition assays. The Pearson coefficients showed a moderate correlation between the antioxidant activity of fluid extracts and their phenolic content, but a strong correlation between anthocyanin and ascorbic acid content. HPLC analysis identified and quantified the main phenolic compounds of chlorogenic and syringic acid, catechin, and glycosylated kaempferol, apigenin, and quercetin, in variable proportions. An in vitro experimental model of steatosis was developed in HepG2 hepatocytes treated with a mixture of free fatty acids. Cell culture analyses showed that cytocompatible concentrations of fluid extracts could significantly reduce the lipid accumulation and inhibit the reactive oxygen species, malondialdehyde, and nitric oxide secretion in stressed hepatocytes. In conclusion, these results put an emphasis on the chemical compounds' high antioxidant and liver protection capacity of unstudied fluid extracts obtained from Romanian cultivars of bitter cherries var. Silva and pomace of red grapes var. Mamaia, similar to the fluid extract of haskap berries var. Loni, in particular, the positive modulation of fat deposition next to oxidative stress and the lipid peroxidation process triggered by fatty acids in HepG2 hepatocytes. Consequently, this study indicated that these fluid extracts could be further exploited as hepatoprotective agents in liver steatosis, which provides a basis for the further development of novel extract mixtures with synergistic activity as anti-obesity products.

Metabolic engineering in Streptomyces albidoflavus for the biosynthesis of the methylated flavonoids sakuranetin, acacetin, and genkwanin

Flavonoids are important plant secondary metabolites showing antioxidant, antitumor, anti-inflammatory, and antiviral activities, among others. Methylated flavonoids are particularly interesting compared to non-methylated ones due to their greater stability and intestinal absorption, which improves their oral bioavailability. In this work we have stablished a metabolic engineered strain of Streptomyces albidoflavus with enhanced capabilities for flavonoid production, achieving a 1.6-fold increase in the biosynthesis of naringenin with respect to the parental strain. This improved strain, S. albidoflavus UO-FLAV-004, has been used for the heterologous biosynthesis of the methylated flavonoids sakuranetin, acacetin and genkwanin. The achieved titers of sakuranetin and acacetin were 8.2 mg/L and 5.8 mg/L, respectively. The genkwanin titers were 0.8 mg/L, with a bottleneck identified in this producing strain. After applying a co-culture strategy, genkwanin production titers reached 3.5 mg/L, which represents a 4.4-fold increase. To our knowledge, this study presents the first biosynthesis of methylated flavonoids in not only any Streptomyces species, but also in any Gram-positive bacteria.

Sakuranetin and its therapeutic potentials - a comprehensive review

Sakuranetin (SKN), a naturally derived 7-O-methylated flavonoid, was first identified in the bark of the cherry tree (Prunus spp.) as an aglycone of sakuranin and then purified from the bark of Prunus puddum. It was later reported in many other plants including Artemisia campestris, Boesenbergia pandurata, Baccharis spp., Betula spp., Juglans spp., and Rhus spp. In plants, it functions as a phytoalexin synthesized from its precursor naringenin and is the only known phenolic phytoalexin in rice, which is released in response to different abiotic and biotic stresses such as UV-irradiation, jasmonic acid, cupric chloride, L-methionine, and the phytotoxin coronatine. Till date, SKN has been widely reported for its diverse pharmacological benefits including antioxidant, anti-inflammatory, antimycobacterial, antiviral, antifungal, antileishmanial, antitrypanosomal, glucose uptake stimulation, neuroprotective, antimelanogenic, and antitumor properties. Its pharmacokinetics and toxicological properties have been poorly understood, thus warranting further evaluation together with exploring other pharmacological properties such as antidiabetic, neuroprotective, and antinociceptive effects. Besides, in vivo studies or clinical investigations can be done for proving its effects as antioxidant and anti-inflammatory, antimelanogenic, and antitumor agent. This review summarizes all the reported investigations with SKN for its health-beneficial roles and can be used as a guideline for future studies.

Phenolic Profile, Antioxidant, Antidiabetic, and Antigout Potential of Stem Extracts of Four Sweet Cherry Cultivars

In order to highlight the activities of bioactive compounds present in the stem of sweet cherries, four different cultivars (Van, Burlat, Napoleon, and Cœur pigeon) were collected in Sefrou city in Morocco and were studied. Several assays were performed for this purpose, such as the quantification of phenolic compounds (TPC, TFC, and CTC) and the evaluation of the antioxidant activity using DPPH, ABTS, and FRAP assays. The phenolic profile of each extract was characterized by UHPLC-DAD/MS analysis. The antidiabetic (α-amylase inhibition) and antigout (xanthine oxidase inhibition) activities were also investigated. The results showed high levels of phenolic compounds, with the values of 340 ± 12.06, 244 ± 10.20, 232 ± 5.07, and 19 ± 3.10 mg gallic acid equivalent/g extract for the cultivars Napoleon, Coeur de pigeon, Van, and Burlat, respectively. According to the same order, the flavonoids showed amounts of 34.31 ± 2.08, 23.75 ± 1.02, 24.37 ± 1.20, and 23.31 ± 0.90 mg (rutin equivalent) RE/g extract. These values were correlated with the results of the antioxidant assays, where the Napoleon cultivar proved to be the most potent using the DPPH (IC₅₀ = 2.51 µg/mL) and ABTS (IC₅₀ = 55.38 µg/mL) assays. The phenolic profile of each extract resulted in the identification of twenty-two compounds belonging to five distinct groups. The major phenolic compounds identified were sakuranetin and dihydrowgonin with their glucosides. Antidiabetic activity assays showed that only stem extracts from Burlat and Napoleon cultivars were able to inhibit the α-amylase enzyme with values of 85.57 ± 1.09% and 68.01 ± 3.52%, respectively. All stem extracts proved their ability to inhibit the xanthine oxidase enzyme which is directly linked to the gout disease, with a high value for Van cultivar (40.63 ± 2.37%). These new findings could provide new opportunities for the valorization of cherry stems for the pharmaceutical application of their active phytochemicals.

Production of (2S)-sakuranetin from (2S)-naringenin in Escherichia coli by strengthening methylation process and cell resistance

(2S)-Sakuranetin is a 7-O-methylflavonoid that has anticancer, antiviral, and antimicrobial activities. Methylation process is involved in biosynthesizing (2S)-sakuranetin from (2S)-naringenin, in which S-adenosylmethionine (SAM) serves as the methyl donor. In this study, after methyl donor and substrate inhibition were identified as limiting factors for (2S)-sakuranetin biosynthesis, an efficient (2S)-sakuranetin-producing strain was constructed by enhancing methyl donor supply and cell tolerance to (2S)-naringenin. Firstly, PfOMT3 from Perilla frutescens was selected as the optimal flavonoid 7-O-methyltransferase (F7-OMT) for the conversion of (2S)-naringenin to (2S)-sakuranetin. Then, the methylation process was upregulated by regulating pyridoxal 5′-phosphate (PLP) content, key enzymes in methionine synthesis pathway, and the availability of ATP. Furthermore, genes that can enhance cell resistance to (2S)-naringenin were identified from molecular chaperones and sRNAs. Finally, by optimizing the fermentation process, 681.44 mg/L of (2S)-sakuranetin was obtained in 250-mL shake flasks. The titer of (2S)-sakuranetin reached 2642.38 mg/L in a 5-L bioreactor, which is the highest titer ever reported. This work demonstrates the importance of cofactor PLP in methylation process, and provides insights to biosynthesize other O-methylated flavonoids efficiently in E. coli.

Composition of Nonextractable Polyphenols from Sweet Cherry Pomace Determined by DART-Orbitrap-HRMS and Their In Vitro and In Vivo Potential Antioxidant, Antiaging, and Neuroprotective Activities

Sweet cherry pomace is an important source of phenolic compounds with beneficial health properties. As after the extraction of phenolic compounds, a phenolic fraction called nonextractable polyphenols (NEPs) remains usually retained in the extraction residue, alkaline and acid hydrolyses and enzymatic-assisted extraction (EAE) were carried out in this work to recover NEPs from the residue of conventional extraction from sweet cherry pomace. In vitro and in vivo evaluation of the antioxidant, antihypertensive, antiaging, and neuroprotective capacities employing Caenorhabditis elegans was achieved for the first time. Extractable phenolic compounds and NEPs were separated and identified by families by high-performance thin-layer chromatography (HPTLC) with UV/Vis detection. A total of 39 phenolic compounds were tentatively identified in all extracts by direct analysis in real-time high-resolution mass spectrometry (DART-Orbitrap-HRMS). EAE extracts presented the highest in vitro and in vivo antioxidant capacity as well as the highest in vivo antiaging and neuroprotective capacities. These results showed that NEPs with interesting biological properties are retained in the extraction residue, being usually underestimated and discarded.

Cherries and Blueberries-Based Beverages: Functional Foods with Antidiabetic and Immune Booster Properties

Nowadays, it is largely accepted that the daily intake of fruits, vegetables, herbal products and derivatives is an added value in promoting human health, given their capacity to counteract oxidative stress markers and suppress uncontrolled pro-inflammatory responses. Given that, natural-based products seem to be a promising strategy to attenuate, or even mitigate, the development of chronic diseases, such as diabetes, and to boost the immune system. Among fruits, cherries and blueberries are nutrient-dense fruits that have been a target of many studies and interest given their richness in phenolic compounds and notable biological potential. In fact, research has already demonstrated that these fruits can be considered functional foods, and hence, their use in functional beverages, whose popularity is increasing worldwide, is not surprising and seem to be a promising and useful strategy. Therefore, the present review reinforces the idea that cherries and blueberries can be incorporated into new pharmaceutical products, smart foods, functional beverages, and nutraceuticals and be effective in preventing and/or treating diseases mediated by inflammatory mediators, reactive species, and free radicals.

Phenolic Compounds Extracted from Cherry Tree (Prunus avium) Branches: Impact of the Process on Cosmetic Properties

Cherry tree branches (Prunus avium var burlat Rosaceae) are agricultural by-products that are often neglected, yet they are rich in phenolic compounds and highly appreciated for their numerous biological activities. Extracts of cherry tree branches were evaluated for their use in cosmetics, particularly for their antioxidant, anti-tyrosinase, and antimicrobial activities. Samples were obtained by accelerated solvent extraction (ASE) at different ethanol percentages and different temperatures. Fourteen phenolic compounds were identified in the extracts by mass spectrometry. Three major compounds were identified (catechin, genistin, and prunin) representing 84 wt% of the total phenolic compounds. Optimal operating conditions maximizing the content of phenolic compounds were determined using a one factor at a time (OFAT) approach (70% aqueous ethanol, 70 °C). The extract obtained under these conditions also showed the highest antioxidant and anti-tyrosinase activities, certainly due to a high catechin content. Although the antimicrobial activities of extracts are less versatile than those of synthetic molecules, they are nonetheless interesting. According to these results, the extracts of cherry tree branches could be used in cosmetics for their interesting properties.

Phytochemical Profiling, Antimicrobial and α-Glucosidase Inhibitory Potential of Phenolic-Enriched Extracts of the Aerial Parts from Echium humile Desf.: In Vitro Combined with In Silico Approach

The current study aimed to evaluate the naturally occurring antimicrobial and antidiabetic potential of various Echium humile (E. humile) solvent extracts (hexane, dichloromethane, ethyl acetate, methanol and aqueous). The bioactive compounds were identified using HPLC-MS, revealing the presence of sixteen phytochemical compounds, with the most abundant being p-coumaric acid, followed by 4,5-di-O-caffeoylquinic acid, trans-ferulic acid and acacetin. Furthermore, E. humile extracts showed marked antimicrobial properties against human pathogen strains, with MIC values for the most relevant extracts (methanol and ethyl acetate) ranging from 0.19 to 6.25 mg/mL and 0.39 to 12.50 mg/mL, respectively. Likewise, methanol was found to be bactericidal towards S. aureus, B. cereus and M. luteus, fungicidal against P. catenulatum and F. oxysporum and have a bacteriostatic/fungicidal effect for the other strains. In addition, the E. humile methanolic extract had the greatest α-glucosidase inhibitory effect (IC50 = 0.06 ± 0.29 mg/mL), which is higher than the standard drug, acarbose (IC50 = 0.80 ± 1.81 mg/mL) and the aqueous extract (IC50 = 0.70 ± 0.67 mg/mL). A correlation study between the major phytochemicals and the evaluated activities was investigated. Docking studies evidenced that most of the identified phenolic compounds showed strong interactions into the binding sites of S. aureus tyrosyl-tRNA synthetase and human lysosomal acid-α-glucosidase, confirming their suitable inhibitory effect. In summary, these results may provide rational support to explore the clinical efficacy of E. humile and its secondary metabolites in the treatment of dual diabetes and infections.

Zimbro (Juniperus communis L.) as a Promising Source of Bioactive Compounds and Biomedical Activities: A Review on Recent Trends

Plant-derived products and their extracted compounds have been used in folk medicine since early times. Zimbro or common juniper (Juniperus communis) is traditionally used to treat renal suppression, acute and chronic cystitis, bladder catarrh, albuminuria, leucorrhea, and amenorrhea. These uses are mainly attributed to its bioactive composition, which is very rich in phenolics, terpenoids, organic acids, alkaloids, and volatile compounds. In the last few years, several studies have analyzed the huge potential of this evergreen shrub, describing a wide range of activities with relevance in different biomedical discipline areas, namely antimicrobial potential against human pathogens and foodborne microorganisms, notorious antioxidant and anti-inflammatory activities, antidiabetic, antihypercholesterolemic and antihyperlipidemic effects, and neuroprotective action, as well as antiproliferative ability against cancer cells and the ability to activate inductive hepato-, renal- and gastroprotective mechanisms. Owing to these promising activities, extracts and bioactive compounds of juniper could be useful for the development of new pharmacological applications in the treatment of several acute and chronic human diseases.

HPLC-DAD phenolics analysis, α-glucosidase, α-amylase inhibitory, molecular docking and nutritional profiles of Persicaria hydropiper L

BACKGROUND

Natural phenolic compounds and Phenolics-rich medicinal plants are also of great interest in the management of diabetes. The current study was aimed to analyze phenolics in P. hydropiepr L extracts via HPLC-DAD analysis and assess their anti-diabetic potentials using in-vitro and in-silico approaches.

METHODS

Plant crude methanolic extract (Ph.Cme) was evaluated for the presence of phenolic compounds using HPLC-DAD analysis. Subsequently, samples including crude (Ph.Cr), hexane (Ph.Hex), chloroform (Ph.Chf), ethyl acetate (Ph.EtAc), butanol (Ph.Bt), aqueous (Ph.Aq) and saponins (Ph.Sp) were tested for α-glucsidase and α-amylase inhibitory potentials and identified compounds were docked against these target enzymes using Molecular Operating Environment (MOE) software. Fractions were also analyzed for the nutritional contents and acute toxicity was performed in animals.

RESULTS

In HPLC-DAD analysis of Ph.Cme, 24 compounds were indentfied and quantified. Among these, Kaemferol-3-(p-coumaroyl-diglucoside)-7-glucoside (275.4 mg g- 1), p-Coumaroylhexose-4-hexoside (96.5 mg g- 1), Quercetin-3-glucoronide (76.0 mg g- 1), 4-Caffeoylquinic acid (58.1 mg g- 1), Quercetin (57.9 mg g- 1), 5,7,3'-Trihydroxy-3,6,4',5'-tetramethoxyflavone (55.5 mg g- 1), 5-Feruloylquinic acid (45.8 mg g- 1), Cyanidin-3-glucoside (26.8 mg g- 1), Delphinidin-3-glucoside (24 mg g- 1), Quercetin-3-hexoside (20.7 mg g- 1) were highly abundant compounds. In α-glucosidase inhibition assay, Ph.Sp were most effective with IC50 value of 100 μg mL-1. Likewise in α-amylase inhibition assay, Ph.Chf, Ph.Sp and Ph.Cme were most potent fractions displayed IC50 values of 90, 100 and 200 μg mL-1 respectively. Docking with the α-glucosidase enzyme revealed top ranked conformations for majority of the compounds with Kaemferol-3-(p-coumaroyl-diglucoside)-7-glucoside as the most active compound with docking score of - 19.80899, forming 14 hydrogen bonds, two pi-H and two pi-pi linkages with the Tyr 71, Phe 158, Phe 177, Gln 181, Arg 212, Asp 214, Glu 276, Phe 300, Val 303, Tyr 344, Asp 349, Gln 350, Arg 439, and Asp 408 residues of the enzyme. Likewise, docking with α-amylase revealed that most of the compounds are well accommodated in the active site residues (Trp 59, Tyr 62, Thr 163, Leu 165, Arg 195, Asp 197, Glu 240, Asp 300, His 305, Asp 356) of the enzyme and Cyanidin-3-rutinoside displayed most active compound with docking score of - 15.03757.

CONCLUSIONS

Phytochemical studies revealed the presence of highly valuable phenolic compounds, which might be responsible for the anti-diabetic potentials of the plant samples.

Anti-Inflammatory and Antiproliferative Properties of Sweet Cherry Phenolic-Rich Extracts

Cherries have largely been investigated due to their high content in phenolics in order to fully explore their health-promoting properties. Therefore, this work aimed to assess, for the first time, the anti-inflammatory potential of phenolic-targeted fractions of the Saco cherry, using RAW 264.7 macrophages stimulated with lipopolysaccharide. Additionally, the cytotoxic effects on gastric adenocarcinoma (AGS), neuroblastoma (SH-SY5Y) and normal human dermal fibroblast (NHDF) cells were evaluated, as well as the ability to protect these cellular models against induced oxidative stress. The obtained data revealed that cherry fractions can interfere with cellular nitric oxide (NO) levels by capturing NO radicals and decreasing inducible nitric oxide synthase and cyclooxygenase-2 expression. Furthermore, it was observed that all cherry fractions exhibited dose-dependent cytotoxicity against AGS cells, presenting cytotoxic selectivity for these cancer cells when compared to SH-SY5Y and NHDF cells. Regarding their capacity to protect cancer cells against oxidative injury, in most assays, the total cherry extract was the most effective. Overall, this study reinforces the idea that sweet cherries can be incorporated into new pharmaceutical products, smart foods and nutraceuticals.

Sweet cherry phenolics revealed to be promising agents in inhibiting P-glycoprotein activity and increasing cellular viability under oxidative stress conditions: in vitro and in silico study

This study aimed to explore the total phenolic and anthocyanin content (TPC and TAC, respectively), and the biological potential of Portuguese sweet cherry cultivars. The TPC and TAC values ranged between 72.9 and 493.6 gallic acid equivalents per 100 g fresh weight (fw), and from 1.0 to 179.1 cyanidin 3-O-rutinoside equivalents per 100 g fw, respectively. Cristalina total extract was the most effective in capturing DPPH reactive species, whereas the colored fraction and the total extract of Saco cultivar were the most efficient in scavenging ferric and peroxide species. Celeste total extract was the most effective in inhibiting α-glucosidase enzyme. Phenolic-rich extracts and standard phenolics also revealed ability to interfere with the P-gp activity on MDCK-II and MDCK-MDR1 cells and to increase cellular viability under conditions of oxidative stress. Computational studies were performed to evaluate the interaction between phenolics and the P-gp activity. This study revealed that cherry extracts and their phenolic compounds present notable biological properties, encouraging the development of cherry-based dietary and medicinal supplements. PRACTICAL APPLICATION: The interest in phenolic-rich sources has increased significantly in recent years, given their capacity to prevent the development of chronic disorders, such as cancer. Recent evidence suggests that phenolic compounds can act as P-glycoprotein (P-gp) inhibitors, an important drug efflux transporter, preventing multidrug resistance, and thus, enhancing the therapeutic efficacy of some drugs in certain target cells. Our results indicate that enriched-fractions from sweet cherries can effectively interfere with the P-gp activity on MDCK-II and MDCK-MDR1 cells and protect against oxidative damage.

Encapsulation of sea buckthorn (Hippophae rhamnoides L.) leaf extract via an electrohydrodynamic method

Polyphenols from the leaves of sea buckthorn (Hippophae rhamnoides L.) are nutritious and bioactive substances that can be used as nutritional supplements. To improve their stability and bioaccessibility in vivo, chemical extracts of sea buckthorn leaves were, for the first time, encapsulated using electrohydrodynamic technology. The microcapsules were characterized using scanning electron microscopy, Fourier-transform infrared spectroscopy, and thermogravimetric analysis. The extract and microcapsules were evaluated for total phenols and flavonoids, total antioxidant activity, and their inhibitory effects on metabolic syndrome-related enzymes (α-glucosidase, α-amylase, and pancreatic lipase) under in vitro simulated digestion. The results indicated that the extract was successfully encapsulated; encapsulation protected polyphenols and flavonoids from degradation and increase their bioaccessibility in the intestine. The antioxidant activity and the inhibition of metabolic syndrome-related enzymes were better reserved after encapsulation. Our findings will help in promoting the potential of sea buckthorn as a nutritional supplement and expanding its commercial use.

Potential Activity of Abrantes Pollen Extract: Biochemical and Cellular Model Studies

The aim of this study was to determine the grain composition and (poly)phenolic profile of pollen from Abrantes (Portugal), as well as its antioxidative and antidiabetic properties, and abilities to protect human erythrocytes against induced hemoglobin oxidation, lipid peroxidation, and hemolysis. The phytochemical profile of the Abrantes’ bee pollen revealed twenty phenolic compounds, identified by high-performance liquid chromatography with electrospray ionization mass spectrometry coupled with photodiode array detection. Among them, quercetin derivatives were the most abundant. Concerning the biological potential, the pollen extract showed notable capacity for 2,2-diphenyl-1-picrylhydrazyl, nitric oxide, and superoxide radicals, as well as for inhibition of α-glucosidase action, and protection of human erythrocytes against oxidative damage. Non-cytotoxic effects regarding the NHDF normal cell line, human adenocarcinoma Caco-2, and human liver HepG2 cells were observed. The results obtained contributed to further research on modes of action related to oxidative damage and metabolic health problems, to generate deeper knowledge of potential health-promoting effects to develop novel pharmaceutical drugs, nutraceuticals, and dietary supplements.

Hepatoprotective Effects of Sweet Cherry Extracts (cv. Saco)

Cancer is the second cause of death worldwide. Among cancers, hepatocellular carcinoma is one of the most prevalent. Evidence indicates that the daily consumption of fruits and vegetables can prevent the onset of various cancers due to the presence of bioactive compounds. Sweet cherries are known for their richness in phenolics, including anthocyanins, which are the major constituents, and presumably, the key contributors to their biological activity. Therefore, the present study aimed to evaluate the effects of three different cherry fractions on human hepatocellular carcinoma (HepG2) cells viability and effectiveness to improve the redox status of these cells under oxidative damage induced by nitric oxide radicals and hydrogen peroxide. Phenolic characterization of fractions was performed by Fourier transform infrared spectroscopy. The obtained results indicated that enriched phenolic fractions of sweet cherries (cv. Saco, can impair cell viability and suppress cells growth after 72 h of exposure, promoting necrosis at the highest tested concentrations (>50 µg/mL). Additionally, fractions also showed the capacity to protect these cells against oxidative injury by capturing radicals before they can attack cells’ membrane and by modulating reactive oxygen and nitrogen species generation, as demonstrated by bioinformatic tools.

Prunus avium L. (Sweet Cherry) By-Products: A Source of Phenolic Compounds with Antioxidant and Anti-Hyperglycemic Properties—A Review

Prunus avium L. (sweet cherry) is one of the most appreciated fruit due to its organoleptic and nutritional value. Interestingly, cherry leaves, stems, and flowers are agri-food by-products rich in bioactive compounds that are mostly still unexploited. Stems and leaves have been used in folk medicine since ancient times. Recently, cherry flowers have also proved to be an interesting source of compounds with therapeutic properties. Phenolic compounds, namely hydroxycinnamic acids and flavonoids, are the most present phytochemicals in P. avium fruits and their by-products. These compounds have shown a good antioxidant potential to prevent oxidative stress-related diseases and glycemic control, fundamental in preventing and controlling diabetes mellitus. The present review summarizes the main phenolics found in P. avium stems, leaves, and flowers as compared to their fruits and describes their antioxidant and anti-hyperglycemic properties. Thus, these by-products are an accessible and low-cost source of bioactive constituents with interesting health-promoting properties, making their use promising in diabetes therapy.

In vitro antioxidant and antibacterial activities with polyphenolic profiling of wild cherry, the European larch and sweet chestnut tree bark

This study is a comparative investigation of antioxidant and antibacterial properties of tree bark extracts of three common European species, Prunus avium L., Larix decidua Mill. and Castanea sativa Mill. The bioactive compounds present in the bark were recovered in 80% aqueous ethanol using ultrasound as the green extraction method. The antioxidant potential of the extracts was assessed with multiple biochemical assays: total phenol content (TPC) expressed in gallic acid equivalent (GAE), 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) expressed in trolox equivalent (TE), and ferric reducing ability of plasma (FRAP) expressed in ascorbic acid equivalent (AAE). Sweet chestnut bark extract showed the highest antioxidant activity with TPC of 174.25 ± 16.95 mg GAE/g dry weight, DPPH (IC50) of 2.69 ± 0.03 μg/mL, ABTS of 739.65 ± 24.41 mg TE/g dry weight and FRAP of 207.49 ± 3.62 mg AAE/g dry weight. The antibacterial activity of the extracts was evaluated by disk diffusion test, minimal inhibitory concentration (MIC) assay and bacterial growth curves. Sweet chestnut bark extract gave IC50 values of 0.25 mg/mL and 1.00 mg/mL against E. coli and S. aureus, respectively. The polyphenolic profiling of the bark extracts was performed to identify the major compounds responsible for the bioactivities using high-performance liquid chromatography/tandem mass spectrometry (HPLC–MS/MS). The bark extracts were rich in natural antioxidants, thus holding tremendous potential for use as natural additives in food industry.

Graphic abstract

Valorisation of Prunus avium L. By-Products: Phenolic Composition and Effect on Caco-2 Cells Viability

Prunus avium L. by-products, such as stems, leaves, and flowers, are used in folk medicine to prevent and treat some diseases. However, their phenolic composition and in vitro bioactivities against tumor cells are poorly known. In this work, we compared the phenolic profile and the biological potential of aqueous infusions and hydroethanolic extracts of P. avium leaves, stems, and flowers from Saco cultivar, collected from the Fundão region (Portugal). Among the fifty-two phenolic compounds tentatively identified by HPLC-DAD-ESI/MSⁿ, the hydroxycinnamic acids were the most abundant. Both extracts of stems revealed a higher activity against DPPH^•. Meanwhile, hydroethanolic extracts from stems and flowers and aqueous infusions of flowers were the most effective in inhibiting the growth of the human epithelial colorectal adenocarcinoma (Caco-2) cells at concentrations above 200 μg/mL. More detailed knowledge about the phenolic composition and health-promoting properties of Portuguese P. avium by-products allows for increasing the biological and commercial value of these bio-wastes, which may have a positive impact on food and pharmaceutical industries, as on the valorization of the local economy.

Chemical Composition, Diuretic, and Antityrosinase Activity of Traditionally Used Romanian Cerasorum stipites

Cherry stems (CS) represent a by-product intensively used in Eastern European countries as a traditional remedy for urinary tract disorders. Ethnopharmacological evidences sustain the use of CS as aqueous preparations (infusion and decoction), but few data were previously reported about phytochemical profile and pharmacological potential of CS hydroalcoholic extracts. In this regard, we aimed to evaluate the phenolic profile, in vitro antioxidant and tyrosinase inhibitory potential, and in vivo diuretic activity of 70% hydroethanolic cherry stems extract and cherry stems decoction (CSD). LC-DAD-ESI/MSⁿ analysis revealed the presence of flavonoid-type compounds as main constituents for both preparations, especially flavanones (naringenin glycosides). Antioxidant activity evaluated through DPPH, ABTS, and FRAP methods was superior for cherry stems extract, probably due to the presence of phenolic-derived compounds in higher amounts than CSD. On the other hand, tyrosinase inhibitory potential and diuretic effect exerted by CSD were stronger, highlighting that other types of hydrophilic secondary metabolites are responsible for this bioactivity. Overall, our findings indicate that CS preparations could be used as promising mild diuretic agents and encourage further investigations regarding the correlation between their chemical composition and bioactive potential.

Comparative chemical analysis of six ancient italian sweet cherry (Prunus avium L.) varieties showing antiangiogenic activity

In this study, cherry fruits and petioles from six ancient Italian Prunus avium L. varieties (Ferrovia, Capellina, Morellina, Ciambellana, Napoletana, and Bianca), were compared by chemical and bioinformatic analyses and evaluated for their antiangiogenic activity. The highest levels of total phenols and flavonoids were found in Napoletana petioles, and Morellina and Capellina fruits. HPLC-PDA-MS analyses showed similar phenolic profiles for all fruit extracts, with cyanidin-3-O-rutinoside, flavonols glycosides, and quinic acid derivatives as major components. Flavonoid glycosides were found in all petiole extracts, while proanthocyanidins B type were predominant in Capellina, Napoletana and Bianca. Accordingly to their higher polyphenolic content, petiole extracts exhibited stronger radical scavenging activity compared to the fruits. The best antiangiogenic response was exhibited by Morellina, Ferrovia, and Ciambellana petiole extracts, and by Ferrovia, Morellina, and Capellina fruit extracts; by bioinformatic studies rutin and cyanidin 3-O-rutinoside were recognised as the best candidate bioactive compounds. In conclusion, sweet cherry varietes were confirmed as valuable sources of phenols, showing also potential angiomodulator properties.

Edible Flowers: Antioxidant Compounds and Their Functional Properties

Edible flowers have been widely consumed for ages until now. The attractive colors and shapes, exotic aroma, and delightful taste make edible flowers very easy to attain. Moreover, they also provide health benefits for consumers due to the unique composition and concentration of antioxidant compounds in the matrices. Knowing the bioactive compounds and their functional properties from edible flowers is necessary to diversify the usage and reach broader consumers. Therefore, this reported review could be useful for functional product development, engaging the discussed edible flowers. We present a comprehensive review of edible flower composition and the functional properties of their antioxidant compounds, mainly phenolics.

Response of chloroplast pigments, sugars and phenolics of sweet cherry leaves to chilling

The aim of the present study was to evaluate the effect of post-flowering chilling of sweet cherry (Prunus avium L.) on the content of biochemical parameters in the leaf (chloroplast pigments, sugars and phenolics). The effect of chilling was investigated in two experiments. Potted 2-year-old trees of cv. 'Grace Star' and 'Schneiders' were exposed to one, two or three consecutive overnight chillings at an average air temperature of 4.7 °C (Experiment I), but in the following year only trees of 'Grace Star' were chilled at 2.2 °C (Experiment II), 3 to 7 weeks after flowering. The analysis of the biochemical parameters was performed by high performance liquid chromatography combined with electrospray ionization mass spectrometry. Chilling at 4.7 °C caused little or no stress, while 2.2 °C induced more intense stress with increased zeaxanthin, sugar and phenolic content in leaves, while exposure of trees to higher temperatures and closer to flowering showed no changes. Two or three consecutive overnight chilling periods increased the phenolic content and enhanced the accumulation of zeaxanthin in the leaves. Sucrose, sorbitol, fructose, total sugar, and total flavonoid content in leaves increased within 48 h after chilling. Zeaxanthin epoxidized within 24 h after one and 48 h after one and two consecutive overnight chillings.

Phenolic Profile and Bioactive Potential of Stems and Seed Kernels of Sweet Cherry Fruit

Every year, large quantities of stems and pits are generated during sweet cherry processing, without any substantial use. Although stems are widely recognized by traditional medicine, detailed and feasible information about their bioactive composition or biological value is still scarce, as well as the characterization of kernels. Therefore, we conducted a study in which bioactivity potential of extracts from stems and kernels of four sweet cherry cultivars (Early Bigi (grown under net cover (C) and without net cover (NC)), Burlat, Lapins, and Van) were examined. The assays included antioxidant (by 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic) acid (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and β-carotene-linoleic acid bleaching assays), and antibacterial activities against important Gram negative and Gram positive bacterial human isolates. Profile and individual phenolic composition of each extract were determined by High-performance liquid chromatography (HPLC) analysis. Extracts from stems of cv. Lapins and kernels of Early Bigi NC presented high levels of total phenolics, flavonoids, ortho-diphenols and saponins. Excepting for cv. Early Bigi NC, major phenolic compounds identified in stems and kernels were sakuranetin and catechin, respectively. In cv. Early Bigi NC the most abundant compounds were ellagic acid for stems and protocatechuic acid for kernels. In all extracts, antioxidant activities showed a positive correlation with the increments in phenolic compounds. Antimicrobial activity assays showed that only stem’s extracts were capable of inhibiting the growth of Gram positive isolates. This new data is intended to provide new possibilities of valorization of these by-products and their valuable properties.

Effects of Different Processing Treatments on Almond (Prunus dulcis) Bioactive Compounds, Antioxidant Activities, Fatty Acids, and Sensorial Characteristics

Almond is one of the most commonly consumed nuts worldwide, with health benefits associated with availability of bioactive compounds and fatty acids. Almond is often eaten raw or after some processing steps. However, the latter can positively or negatively influence chemical and sensorial attributes of almonds. This work was carried out to assess the effects of two processing treatments, namely; roasting and blanching on (i) contents of bioactive compounds, (ii) contents of fatty acids (3) antioxidant activities (4), sensorial characteristics of four neglected Portuguese almond cultivars (Casanova, Molar, Pegarinhos and Refêgo) and two foreign cultivars (Ferragnès and Glorieta). Results showed that in general, levels of bioactive compounds and antioxidant activities increased with roasting and decreased with blanching. Fatty acid profiles of raw kernels of all cultivars were generally identical although Refêgo exhibited a high content of α-linolenic acid. Following roasting and blanching, content of polyunsaturated fatty acids increased while saturated fatty acids, monounsaturated fatty acids and several health lipid indices decreased. Roasting positively affected perception of skin color and sweetness of Ferragnès and Glorieta as well as skin roughness of Molar and Pegarinhos. Blanching on the other hand led to positive changes in textural properties of Refêgo and Pegarinhos. This study reveals the nutritive benefits of consuming neglected almond cultivars in Portugal, and the novel data reported here could be of interest to growers, processing companies and consumers.

Multitarget protection of Pterospartum tridentatum phenolic-rich extracts against a wide range of free radical species, antidiabetic activity and effects on human colon carcinoma (Caco-2) cells

Pterospartum tridentatum is an edible endemic plant common in Portugal. Its flowers are used in culinary and are part of the popular medicine owing to its therapeutic properties. In this study, P. tridentatum flower infusion and hydroethanolic extracts were characterized concerning their phenolic composition and biological potential. By high-performance liquid chromatography method coupled to a diode array detector analysis were detected 13 phenolics. Genistein was the major one. Concerning the biological potential, the hydroethanolic extract was the most active against 2,2-diphenyl-1-picrylhydrazyl^● and also as α-glucosidase inhibitor, while the infusion proved to be a remarkable free radical scavenger. Concerning human epithelial colorectal adenocarcinoma (Caco-2) cells, it was observed that both extracts displayed dose-dependent cytotoxicity on the viability of Caco-2 cells, presenting cytotoxic selectivity for these cancer cells when compared to the NHDF normal cell line. Additionally, they also showed protective effects against oxidative stress induced by tert-butyl hydroperoxide on Caco-2 cells. The obtained results suggest that these extracts may be interesting to enrich nutraceutical, pharmaceutical and food industries; however, more studies need to be done for their inclusion in pharmaceutical preparations and/or food additives. PRACTICAL APPLICATION: Pterospartum tridentatum is an endemic plant commonly used in folk medicine due to its depurative and hypoglycaemic properties. For this reason, we decided to determine the phenolic content of infusion and hydroethanolic extracts of P. tridentatum and their biological potential. The obtained results proved that P. tridentatum extracts are a rich source of bioactive compounds and possess great antioxidant and antidiabetic activities, ability to protect human erythrocytes against oxidative damage, inhibiting hemolysis, hemoglobin oxidation, and lipid peroxidation, and to interfere with Caco-2 cells growth and to protect these cells when subject to tert-butyl hydroperoxide oxidative stress conditions.

Evaluation of in vitro α-amylase and α-glucosidase inhibitory potential and hemolytic effect of phenolic enriched fractions of the aerial part of Salvia officinalis L

BACKGROUND

The inhibition of α-amylase and α-glucosidase activities is one of the major practical strategies for the control of postprandial hyperglycemia. Salvia officinalis L. is known by its various bioactive compounds and its effective therapeutic properties towards illnesses including diabetes.

OBJECTIVE

The present study aimed to evaluate the in vitro inhibitory effect of S. officinalis on key digestive enzymes linked to type 2 diabetes and to identify its hemolytic effect.

METHODS

Hydro-methanol decoction extract and fractions of ethyl acetate and n-butanol were investigated for their in vitro α-amylase and α-glucosidase inhibitory activities, compared to acarbose as a standard. Furthermore, they were evaluated for their hemolytic effect.

RESULTS

Phytochemical composition demonstrated the richness of S. officinalis in secondary metabolites. Extract and fractions inhibited the activity of both enzymes. They showed weak hemolytic activity. Quantitative estimation of total phenolic and flavonoids revealed that ethyl acetate fraction contained the highest amount of these compounds (450.51 ± 0.6 μg GAE/mg DE and 352.01 ± 0.78 μg CE/mg of DE, respectively). It showed the best antidiabetic activity tested both by α-amylase and α-glucosidase assays (IC₅₀ = 46.52 ± 2.68 and 104.58 ± 0.06 μg/mL, respectively). Moreover, this fraction showed the least hemolytic effect (11.58 ± 0.1%).

CONCLUSIONS

S. officinalis extract and fractions are promising sources of α-amylase and α-glucosidase inhibitors.

Cherry stem infusions: antioxidant potential and phenolic profile by UHPLC-ESI-QTOF-MS

This study highlights not only the antioxidant potential of cherry stem infusion but also the need to globally harmonize the control and regulation of herbal products.