Polyphenolic Profile, Antioxidant and Anti-Inflammatory Activity of Eastern Teaberry (Gaultheria procumbens L.) Leaf Extracts

Polyphenols: Secondary Metabolites with a Biological Impression

Polyphenols are natural compounds which are plant-based bioactive molecules, and have been the subject of growing interest in recent years. Characterized by multiple varieties, polyphenols are mostly found in fruits and vegetables. Currently, many diseases are waiting for a cure or a solution to reduce their symptoms. However, drug or other chemical strategies have limitations for using a treatment agent or still detection tool of many diseases, and thus researchers still need to investigate preventive or improving treatment. Therefore, it is of interest to elucidate polyphenols, their bioactivity effects, supplementation, and consumption. The disadvantage of polyphenols is that they have a limited bioavailability, although they have multiple beneficial outcomes with their bioactive roles. In this context, several different strategies have been developed to improve bioavailability, particularly liposomal and nanoparticles. As nutrition is one of the most important factors in improving health, the inclusion of plant-based molecules in the daily diet is significant and continues to be enthusiastically researched. Nutrition, which is important for individuals of all ages, is the key to the bioactivity of polyphenols.

Vaccinium myrtillus L. Leaf Waste as a Source of Biologically Potent Compounds: Optimization of Polyphenol Extractions, Chemical Profile, and Biological Properties of the Extracts

The aims of the present research include (1) optimization of extraction from Vaccinium myrtillus leaf waste via investigation of plant material:medium ratio, extraction medium, and extraction period, employing extractions at room and high temperatures, or using ultrasound and microwaves (M, HAE, UAE, and MAE, respectively), (2) physicochemical characterization, and (3) investigation of extract biological potential. The statistical analysis revealed that optimal levels of parameters for the greatest polyphenolic yield were a proportion of 1:30 g/mL, ethyl alcohol 50% (v/v) during 2 min of microwave irradiation. By LC-MS analysis, 29 phenolic components were detected; HAE showed the highest richness of almost all determined polyphenols, while chlorogenic acid and quercetin 3-O-glucuronide were dominant. All extracts showed a high inhibition of Staphylococcus aureus growth. The effect of different parameters on extracts' antioxidant capacity depended on the used tests. The extracts also showed a stimulative influence on keratinocyte viability and anti-inflammatory activity (proven in cell-based ELISA and erythrocyte stabilization assays). The extraction procedure significantly affected the extraction yield (MAE ≥ maceration ≥ UAE ≥ HAE), whereas conductivity, density, surface tension, and viscosity varied in a narrow range. The presented research provides evidence on the optimal extraction conditions and technique, chemical composition, and antioxidant, antimicrobial, anti-inflammatory, and keratinocyte viability properties of bilberry extracts for potential applications in pharmacy and cosmetics.

Anti-inflammatory, antioxidant and photoprotective activity of standardised Gaultheria procumbens L. leaf, stem, and fruit extracts in UVA-irradiated human dermal fibroblasts

ETHNOPHARMACOLOGICAL RELEVANCE

Gaultheria procumbens L. is a polyphenolic-rich medicinal and food plant. Its leaves, stems, and fruits are traditional anti-inflammatory, antipyretic, antioxidant, and antimicrobial herbal medicines used to treat internal and external inflammation-related ailments, including rheumatic diseases, influenza, the common cold, fever, and skin and periodontal problems. Moreover, G. procumbens leaf extract is used for skin care as an anti-ageing and anti-wrinkle ingredient.

AIM OF THE STUDY

Various environmental factors, especially solar ultraviolet radiation, accelerate skin ageing by promoting oxidative stress and inflammation. Despite the dermoprotective and anti-ageing applications, the impact of G. procumbens on human dermal fibroblasts is unknown. Therefore, the study aimed to evaluate the anti-inflammatory, antioxidant, and photoprotective activity of G. procumbens standardised leaf, stem, and fruit extracts in cellular models, including human dermal fibroblasts (Hs68 cells) under UVA-irradiation, the primary pro-ageing skin stressor.

MATERIALS AND METHODS

Hs68 fibroblasts were pre-treated (24h) with G. procumbens extracts (0.5-100 μg/mL) or reference compounds followed by UVA-irradiation (8 J/cm2). Cell viability and metabolic activity were measured by CCK-8 and MTT assays in human Hs68 and mouse L929 fibroblasts, respectively. The ROS level, SOD, and GST activities were estimated by fluorescence and spectrophotometric techniques. The pro-inflammatory potential (NF-κB transcription factor activation) was checked using THP1-Blue™ NF-κB cells, and the anti-inflammatory activity was studied by measuring IL-8, ICAM-1, and NF-κB levels and phosphorylation of Erk kinase in LPS-stimulated Hs68 cells by spectrophotometry and confocal microscopy. The UVA-induced DNA damage and cell migration were evaluated by comet and scratch assays, respectively.

RESULTS

The extracts did not affect the metabolic activity of mouse L929 fibroblasts and the viability of unirradiated human Hs68 cells. Additionally, the extracts noticeably enhanced the viability of UVA-irradiated Hs68 cells up to 115-120% (p < 0.001) for stem and leaf extract at 25 μg/mL. All extracts in a wide concentration range (0.5-100 μg/mL) did not activate monocytes or induce the NF-κB transcription factor in LPS-stimulated Hs68 fibroblasts. On the other hand, the extracts (5-25 μg/mL) restored the activity of endogenous antioxidant enzymes, i.e., SOD and GST, up to 120-140% (p < 0.001) in the UVA-irradiated Hs68 cells. Moreover, a statistically significant reduction of ROS, IL-8, ICAM-1, and NF-κB levels by up to 48%, 88%, 43%, and 39%, respectively (p < 0.001) and strong suppression of Erk kinase activation was observed for the extracts (25-50 μg/mL) in LPS-stimulated human fibroblasts. The total DNA damage (% tail DNA) in irradiated Hs68 cells was also strongly decreased by up to 66-69% (p < 0.001) at 50 μg/mL. However, the treatment with the extracts did not relevantly enhance the cell migration of Hs68 fibroblasts.

CONCLUSIONS

The results suggest that G. procumbens may effectively protect human skin fibroblast from UVA irradiation. The leaf and stem extracts were the most potent antioxidants, while fruit and stem extracts revealed the strongest anti-inflammatory activity. The observed effects support the traditional use of aerial plant parts (leaves, stems, and fruits) in treating inflammation-related skin disorders cross-linked with oxidative stress and the topical application of Gaultheria extracts as anti-ageing agents intended for skin care.

Phytochemistry and Biological Profile of Gaultheria procumbens L. and Wintergreen Essential Oil: From Traditional Application to Molecular Mechanisms and Therapeutic Targets

Gaultheria procumbens L. is a medicinal plant whose aerial parts (leaves, stems, and fruits) and methyl salicylate-rich essential oil (wintergreen oil) are used in phytotherapy to treat inflammation, muscular pain, and infection-related disorders. This overview summarises the current knowledge about ethnobotany, phytochemistry, pharmacology, molecular mechanisms, biocompatibility, and traditional use of G. procumbens and the wintergreen oil distilled from different plant organs. Over 70 hydrophilic compounds, including methyl salicylate glycosides, flavonoids, procyanidins, free catechins, caffeoylquinic acids, and simple phenolic acids, have been identified in G. procumbens plant parts. Moreover, aliphatic compounds, triterpene acids, and sterols have been revealed in lipophilic fractions. Furthermore, over 130 volatile compounds have been detected in wintergreen oil with dominating methyl salicylate (96.9-100%). The accumulated research indicates that mainly hydrophilic non-volatiles are responsible for the pharmacological effects of G. procumbens, primarily its potent anti-inflammatory, antioxidant, and photoprotective activity, with mechanisms verified in vitro and ex vivo in cellular and cell-free assays. The biological effectiveness of the dominant methyl salicylate glycoside-gaultherin-has also been confirmed in animals. Wintergreen oil is reported as a potent anti-inflammatory agent exhibiting moderate antioxidant and antimicrobial activity in vitro and significant insecticidal and larvicidal capacity. Together, G. procumbens accumulate a diverse fraction of polyphenols, triterpenes, and volatiles with validated in vitro and ex vivo biological activity but with the absence of in vivo studies, especially clinical trials concerning effective dose determination and toxicological verification and technological research, including drug formulation.

Castanea sativa Mill. Leaf: UHPLC-HR MS/MS Analysis and Effects on In Vitro Rumen Fermentation and Methanogenesis

Castanea sativa Mill. (Fagaceae) is a deciduous tree grown for its wood and edible fruits. Chestnut processing produces residues (burs, shells, and leaves) exploitable for their diversity in bioactive compounds in animal nutrition. In fact, plant-specialized metabolites likely act as rumen modifiers. Thus, the recovery of residual plant parts as feed ingredients is an evaluable strategy. In this context, European chestnut leaves from northern Germany have been investigated, proving to be a good source of flavonoids as well as gallo- and ellagitannins. To this purpose, an alcoholic extract was obtained and an untargeted profiling carried out, mainly by means of ultra-high-performance liquid chromatography/high-resolution tandem mass spectrometry (UHPLC-HR MS/MS) techniques. To better unravel the polyphenol constituents, fractionation strategies were employed to obtain a lipophilic fraction and a polar one. This latter was highly responsive to total phenolic and flavonoid content analyses, as well as to antiradical (DPPH^● and ABTS^+●) and reducing activity (PFRAP) assays. The effect of the alcoholic extract and its fractions on rumen liquor was also evaluated in vitro in terms of fermentative parameter changes and impact on methanogenesis. The data acquired confirm that chestnut leaf extract and the fractions therefrom promote an increase in total volatile fatty acids, while decreasing acetate/propionate ratio and CH₄ production.

Tackling the Future Pandemics: Broad-Spectrum Antiviral Agents (BSAAs) Based on A-Type Proanthocyanidins

A-type proanthocyanidins (PAC-As) are plant-derived natural polyphenols that occur as oligomers or polymers of flavan-3-ol monomers, such as (+)-catechin and (-)-epicatechin, connected through an unusual double A linkage. PAC-As are present in leaves, seeds, flowers, bark, and fruits of many plants, and are thought to exert protective natural roles against microbial pathogens, insects, and herbivores. Consequently, when tested in isolation, PAC-As have shown several biological effects, through antioxidant, antibacterial, immunomodulatory, and antiviral activities. PAC-As have been observed in fact to inhibit replication of many different human viruses, and both enveloped and non-enveloped DNA and RNA viruses proved sensible to their inhibitory effect. Mechanistic studies revealed that PAC-As cause reduction of infectivity of viral particles they come in contact with, as a result of their propensity to interact with virion surface capsid proteins or envelope glycoproteins essential for viral attachment and entry. As viral infections and new virus outbreaks are a major public health concern, development of effective Broad-Spectrum Antiviral Agents (BSAAs) that can be rapidly deployable even against future emerging viruses is an urgent priority. This review summarizes the antiviral activities and mechanism of action of PAC-As, and their potential to be deployed as BSAAs against present and future viral infections.

Exploring Vaccinium vitis-idaea L. as a potential source of therapeutic agents: antimicrobial, antioxidant, and anti-inflammatory activities of extracts and fractions

ETHNOPHARMACOLOGICAL RELEVANCE

Vaccinium vitis-idaea L. (lingonberry) leaves and fruits have traditionally been used in Asian and European countries as a natural solution for urinary tract infections, gastrointestinal distress, neurodegenerative diseases, and related inflammatory disorders, which are overall associated with free radical damage and presence of triggering pathogenic strains in the human body. Considering growing attention to natural products, there are not enough scientific data to confirm predominant specialized metabolites, responsible for the traditional therapeutic use of lingonberries.

AIM OF THE STUDY

The present study aimed at an in-depth study of specialized metabolite profiling and biological activity evaluation of lingonberry crude extracts and isolated fractions.

MATERIALS AND METHODS

Crude dry extracts and fractions from lingonberry leaves and fruits were analyzed by the UPLC-MS method. Potential inhibiting properties against different bacterial strains and hyaluronidase, ability to scavenge hydrogen peroxide, and effect on its production in a macrophage culture J774 were examined.

RESULTS

Findings suggested the tentative presence of 59 compounds, mainly phenolics, displayed higher bioactivities of particular fractions than that of crude extracts and elucidated particular compounds as candidates in pharmaceuticals. Trimeric and dimeric proanthocyanidins from lingonberry leaves and fruits were shown to have the strongest antimicrobial, antioxidant, and anti-inflammatory potential.

CONCLUSIONS

This study revealed specialized metabolites responsible for the traditional medicinal properties of lingonberries and pointed out demand for further purification and new research directions of proanthocyanidins in the frame of their multipharmacological perspectives.

The Effect of Standardised Leaf Extracts of Gaultheria procumbens on Multiple Oxidants, Inflammation-Related Enzymes, and Pro-Oxidant and Pro-Inflammatory Functions of Human Neutrophils

The leaves of Gaultheria procumbens are polyphenol-rich traditional medicines used to treat inflammation-related diseases. The present study aimed to optimise the solvent for the effective recovery of active leaf components through simple direct extraction and verify the biological effects of the selected extract in a model of human neutrophils ex vivo. The extracts were comprehensively standardised, and forty-one individual polyphenols, representing salicylates, catechins, procyanidins, phenolic acids, and flavonoids, were identified by UHPLC–PDA–ESI–MS³. The chosen methanol–water (75:25, v/v) extract (ME) was obtained with the highest extraction yield and total phenolic levels (397.9 mg/g extract’s dw), including 98.9 mg/g salicylates and 299.0 mg/g non-salicylate polyphenols. In biological tests, ME revealed a significant and dose-dependent ability to modulate pro-oxidant and pro-inflammatory functions of human neutrophils: it strongly reduced the ROS level and downregulated the release of pro-inflammatory cytokines and tissue remodelling enzymes, especially IL-1β and elastase 2, in cells stimulated by fMLP, LPS, or fMLP + cytochalasin B. The extracts were also potent direct scavengers of in vivo relevant oxidants (O₂^•−, ^•OH, and H₂O₂) and inhibitors of pro-inflammatory enzymes (cyclooxygenase-2, hyaluronidase, and lipoxygenase). The statistically significant correlations between the tested variables revealed the synergic contribution of individual polyphenols to the observed effects and indicated them as useful active markers for the standardisation of the extract/plant material. Moreover, the safety of ME was confirmed in cytotoxicity tests. The obtained results might partially explain the ethnomedicinal application of G. procumbens leaves and support the usage of the standardised leaf extract in the adjuvant treatment of oxidative stress and inflammation-related chronic diseases.

Screening for the Active Anti-Inflammatory and Antioxidant Polyphenols of Gaultheria procumbens and Their Application for Standardisation: From Identification through Cellular Studies to Quantitative Determination

Aerial parts, leaves, and stems of Gaultheria procumbens are polyphenol-rich herbal medicines with anti-inflammatory and antioxidant effects. The present study focused on identifying active markers of the G. procumbens extracts in an integrated approach combining phytochemical and biological capacity tests. The target compounds, representing all classes of Gaultheria polyphenols, were pre-selected by LC-ESI-PDA-MS/MS. For unambiguous identification, the key analytes, including a rare procyanidin trimer (cinnamtannin B-1), miquelianin potassium salt, and two new natural products: quercetin and kaempferol 3-O-β-d-xylopyranosyl-(1→2)-β-d-glucuronopyranosides, were isolated by preparative HPLC and investigated by spectroscopy (HR-ESI-MS, UV-vis, CD, 1D- and 2D-NMR), thiolysis, flame photometry, optical rotation experiments, and absolute configuration studies. The significant contribution of the pre-selected compounds to the biological effects of the extracts was confirmed in vitro: the analytes significantly and in a dose-dependent manner down-regulated the pro-oxidant and pro-inflammatory functions of human neutrophils ex vivo (inhibited the release of reactive oxygen species, IL-1β, TNF-α, and neutrophils elastase, ELA-2), inhibited two key pro-inflammatory enzymes (cyclooxygenase, COX-2, and hyaluronidase), and most of them, except gaultherin, exerted potent direct antioxidant activity (ferric reducing antioxidant power and superoxide anion scavenging capacity). Moreover, cellular safety was confirmed for all compounds by flow cytometry. Eventually, as these mechanisms have been connected to the health benefits of G. procumbens, 11 polyphenols were accepted as active markers, and a simple, accurate, reproducible, and fully validated RP-HPLC-PDA method for standardisation of the target extracts was proposed.

UHPLC-MS Chemical Fingerprinting and Antioxidant, Antiproliferative, and Enzyme Inhibition Potential of Gaultheria pumila Berries

Gaultheria pumila (Ericaceae) (known as Chaura or Mutilla) is a Chilean native small shrub that produces berry fruits consumed by local Mapuche people. In this study, the chemical fingerprinting and antioxidant, enzyme inhibition, and antiproliferative activities of the berries were investigated for the first time. Thirty-six metabolites were identified in the fruits by ultra-high performance liquid chromatography-photodiode array detection, hyphenated with Orbitrap mass spectrometry analysis (UHPLC-DAD-Orbitrap-MS). Metabolites, included anthocyanins, phenolic acids, flavonoids, iridoids, diterpenes, and fatty acids. Moderate inhibitory activities against acetylcholinesterase (7.7 ± 0.3 µg/mL), butyrylcholinesterase (34.5 ± 0.5 µg/mL), and tyrosinase (3.3 ± 0.2 µg/mL) enzymes were found. Moreover, selected major compounds were subjected to docking assays in light of their experimental inhibition. Results indicated that hydrogen bonding, π–π interaction, and a salt bridge interaction contributed significantly. Gaultheria pumila berries showed a total phenolic content of 189.2 ± 0.2 mg of gallic acid equivalents/g, total flavonoid content of 51.8 ± 0.1 mg quercetin equivalents/g, and total anthocyanin content of 47.3 ± 0.2 mg of cianydin-3-glucoside equivalents/g. Antioxidant activity was assessed using DPPH (92.8 ± 0.1 µg/mL), FRAP (134.1 ± 0.1 μmol Trolox equivalents/g), and ORAC (4251.6 ± 16.9 μmol Trolox equivalents/g) assays. Conversely, Gaultheria pumila showed a scarce antiproliferative potential against several solid human cancer cells. Our findings suggest that Gaultheria pumila berries have several bioactive metabolites with inhibitory effects against acetylcholinesterase, butyrylcholinesterase, and tyrosinase, and have the potential for use in food supplements.

Antihyperglycemic effect and phytochemical investigation of Rubia cordifolia (Indian Madder) leaves extract

Medicinal plants are used as an important source of medicines in pharmaceutical industry. Rubia cordifolia is widely used to cure diabetes mellitus. Present study was aimed to investigate the antihyperglycemic effects of different fractions of R. cordifolia leaves and to analyze its antioxidant effect and phytochemical composition. Male albino mice were randomly distributed into seven groups (n = 7). Group-I was normal control, group-II was Alloxan (100 mg/kg)-induced diabetic control, and group-III was standard drug (Glibenclamide 0.5 mg/kg)-treated group. Animals in groups IV–VII were treated with n-hexane fraction, ethyl acetate fraction, n-butanol fraction and aqueous fraction of R. cordifolia, orally administered (100 mg/kg) once daily up to 28 days after Alloxan induction, respectively. Methanolic extract (ME) and fractions of R. cordifilia were analyzed for antioxidant activity and quantification of total phenolic content and total flavonoid content. HPLC of ME and most active fractions were performed. The results showed that RCEF (G-V) and RCBF (G-VI) have significantly (P < 0.05) reduced the increased level of glucose as compared to toxicant control group. It was further revealed that EF and BF have higher antioxidant activity (having IC50 34.9, 36.86 (µg/mL)) owing to phenolic and flavonoid identified by HPLC.

Phytochemical characterization, genotoxicity, cytotoxicity, and antimicrobial activity of Gautheria procumbens essential oil

This study investigated the chemical constituents of Gaultheria procumbens essential oil and is the first to relate cytogenotoxicity with oxidative metabolism and antimicrobial activity. Chromatographic analysis of the essential oil showed methyl salicylate (99.96%) and linalool (0.04%) as the major compounds. The essential oil showed no signs of cytogenotoxicity at different concentrations (1.82 to 58.34 mg mL^-1). Furthermore, G. procumbens essential oil and methyl salicylate were used to evaluate the minimal inhibitory concentrations (MIC) and minimal microbicidal concentrations (MMC). The results showed efficacy against several microorganisms, including Aeromonas caviae, Candida albicans, and Mycobacterium fortuitum with MIC values ranging from 1.82 to 3.64 mg mL^-1 and MMC values ranging from 3.64 to 12.67 mg mL^-1, which were confirmed by time-kill kinetics. Based on our results, the essential oil is a promising alternative to developing future formulations to treat infections caused by microorganisms.

Identification and accumulation of phenolic compounds in the leaves and bark of Salix alba (L.) and their biological potential

The study examines the phenolic compounds in hydromethanolic extracts of Salix alba (L.) leaves and bark as well as their antioxidant activity and cytotoxic potential. UPLC-PDA-Q/TOF-MS analysis showed a total of 29 phenolic compounds in leaves and 34 in bark. Total phenolic compound content was 5575.96 mg/100 g of dry weight (DW) in leaves and 2330.31 mg/100 g DW in bark. The compounds were identified as derivatives of phenolic acids (seven in leaves and five in bark), flavanols and procyanidins (eight in leaves and 26 in bark) and flavonols (14 in leaves and three in bark). Both extracts exhibited strong antioxidant potential, assessed by radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS), but the bark extract was even stronger than the ascorbic acid used as a standard. The cytotoxicity of both extracts was evaluated against human skin fibroblasts and human epidermal keratinocytes cell lines using the Presto Blue cell viability assay. The keratinocytes were more resistant to tested extracts than fibroblasts. The leaf and bark extracts at concentrations which exhibited antioxidant activity were also not toxic against the keratinocyte cell line. Thus, S. alba extracts, especially the leaf extract, offer promise as a nontoxic natural antioxidant, in cosmetic products or herbal medicines, and as a source of bioactive secondary metabolites.

Biological and chemical insight into Gaultheria procumbens fruits: a rich source of anti-inflammatory and antioxidant salicylate glycosides and procyanidins for food and functional application

The fruits of Gaultheria procumbens are traditionally used for culinary and healing purposes as anti-inflammatory agents. In the present work, the active components of the fruits were identified (UHPLC-PDA-ESI-MS3, preparative HPLC isolation, and NMR structural studies), and their biological capacity was evaluated in vitro in cell-based and non-cellular models. The fruits were revealed to be the richest known dietary source of salicylates (38.5 mg per g fruit dw). They are also rich in procyanidins (28.5 mg per g fruit dw). Among five tested solvents, acetone was the most efficient in concentrating the phenolic matrix (39 identified compounds; 191.3 mg g-1, 121.7 mg g-1, and 50.9 mg g-1 dry extract for total phenolics, salicylates, and procyanidins, respectively). In comparison to positive controls (dexamethasone, indomethacin, and quercetin), the extract (AE) and pure salicylates exhibited strong inhibitory activity towards pro-inflammatory enzymes (cyclooxygenase-2 and hyaluronidase). The analytes were found to be non-cytotoxic (flow cytometry) towards human neutrophils ex vivo. Moreover, they significantly, in a dose-dependent manner, downregulated the release of ROS, TNF-α, IL-1β, and elastase-2 and slightly inhibited the secretion of IL-8 and metalloproteinase-9 in the cells. The observed effects might support the usage of G. procumbens fruits as functional components of an anti-inflammatory diet and indicate the potential of AE for use in adjuvant treatment of inflammatory disorders cross-linked with oxidative stress and associated with the excessive production of TNF-α, IL-1β, and elastase-2.

Salicylate and Procyanidin-Rich Stem Extracts of Gaultheria procumbens L. Inhibit Pro-Inflammatory Enzymes and Suppress Pro-Inflammatory and Pro-Oxidant Functions of Human Neutrophils Ex Vivo

Salicylate-rich plants are an attractive alternative to synthetic anti-inflammatory drugs due to a better safety profile and the advantage of complementary anti-inflammatory and antioxidant effects of the co-occurring non-salicylate phytochemicals. Here, the phytochemical value and biological effects in vitro and ex vivo of the stems of one of such plants, Gaultheria procumbens L., were evaluated. The best extrahent for effective recovery of the active stem molecules was established in comparative studies of five extracts. The UHPLC-PDA-ESI-MS³, HPLC-PDA, and UV-photometric assays revealed that the selected acetone extract (AE) accumulates a rich polyphenolic fraction (35 identified constituents; total content 427.2 mg/g dw), mainly flavanols (catechins and proanthocyanidins; 201.3 mg/g dw) and methyl salicylate glycosides (199.9 mg/g dw). The extract and its model components were effective cyclooxygenase-2, lipoxygenase, and hyaluronidase inhibitors; exhibited strong antioxidant capacity in six non-cellular in vitro models (AE and procyanidins); and also significantly and dose-dependently reduced the levels of reactive oxygen species (ROS), and the release of cytokines (IL-1β, IL-8, TNF-α) and proteinases (elastase-2, metalloproteinase-9) in human neutrophils stimulated ex vivo by lipopolysaccharide (LPS) and N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP). The cellular safety of AE was demonstrated by flow cytometry. The results support the application of the plant in traditional medicine and encourage the use of AE for development of new therapeutic agents.

The Effect of Standardised Flower Extracts of Sorbus aucuparia L. on Proinflammatory Enzymes, Multiple Oxidants, and Oxidative/Nitrative Damage of Human Plasma Components In Vitro

Polyphenol-rich plant extracts might alleviate the negative impact of oxidative stress and inflammation, but careful phytochemical standardisation and evaluation of various mechanisms are required to fully understand their effects. In this context, flower extracts of Sorbus aucuparia L.-a traditional medicinal plant-were investigated in the present work. The LC-MS/MS profiling of the extracts, obtained by fractionated extraction, led to the identification of 66 constituents, mostly flavonols (quercetin and sexangularetin glycosides with dominating isoquercitrin), pseudodepsides of quinic and shikimic acids (prevailing isomers of chlorogenic acid and cynarin), and flavanols (catechins and proanthocyanidins). Minor extract components of possible chemotaxonomic value were flavalignans (cinchonain I isomers) and phenylamides (spermidine derivatives). As assessed by HPLC-PDA and UV-spectrophotometric studies, the extracts were polyphenol-abundant, with the contents up to 597.6 mg/g dry weight (dw), 333.9 mg/g dw, 382.0 mg/g dw, and 169.0 mg/g dw of total phenolics, flavonoids, proanthocyanidins, and caffeoylquinic acids, respectively. Their biological in vitro effects were phenolic-dependent and the strongest for diethyl ether, ethyl acetate, and n-butanol fractions of the methanol-water (7 : 3, v/v) extract. The extracts showed significant, concentration-dependent ability to scavenge in vivo-relevant radical/oxidant agents (O₂ ^∙-, OH^∙, H₂O₂, ONOO^-, NO^∙, and HClO) with the strongest effects towards OH^∙, ONOO^-, HClO, and O₂ ^∙- (compared to ascorbic acid). Moreover, the extracts efficiently inhibited lipoxygenase and hyaluronidase (compared to indomethacin) but were inactive towards xanthine oxidase. At in vivo-relevant levels (1-5 μg/mL), they also effectively protected human plasma components (proteins and lipids) against ONOO^--induced oxidative damage (reduced the levels of 3-nitrotyrosine, lipid hydroperoxides, and thiobarbituric acid-reactive substances) and normalised/enhanced the total nonenzymatic antioxidant capacity of plasma. In cytotoxicity tests, the extracts did not affect the viability of human PBMCs and might be regarded as safe. The results support the application of the extracts in the treatment of oxidative stress-related pathologies cross-linked with inflammatory changes.

Redox regulation and NO/cGMP plus K+ channel activation contributes to cardiorenal protection induced by Cuphea carthagenensis (Jacq.) J.F. Macbr. in ovariectomized hypertensive rats

BACKGROUND

One of the medicinal plants widely used by the population in the treatment of hypertension, atherosclerosis and circulatory disorders is Cuphea carthagenensis (Jacq.) J.F. Macbr. (Lythraceae), popularly known as 'sete sangrias', being found in Brazil, Hawaii and in South Pacific Islands. Despite the widespread use of this species by the population, its long-term antihypertensive and cardioprotective activities have not yet been scientifically evaluated.

PURPOSE

To evaluate the possible cardioprotective effects of an ethanol-soluble fraction obtained from C. carthagenensis (ESCC) using ovariectomized hypertensive rats to simulate a broad part of the female population over 50 years of age affected by hypertension. In addition, the molecular mechanism that may be responsible for its cardiorenal protective effects was also explored.

METHODS

Female Wistar rats were submitted to surgical procedures of bilateral ovariectomy and induction of renovascular hypertension (two-kidneys, one-clip model). The sham-operated group was used as negative control. ESCC was obtained and a detailed phytochemical investigation about its main secondary metabolites was performed. ESCC was orally administered at doses of 30, 100 and 300  mg/kg, daily, for 28 days, 5 weeks after surgery. Enalapril (15  mg/kg) was used as standard antihypertensive drug. Renal function was evaluated on days 1, 7, 14, 21 and 28. At the end of the experimental period, systolic, diastolic, mean arterial pressure and heart rate were recorded. The activity of the tissue enzymatic antioxidant system, thiobarbituric acid reactive substances, nitrotyrosine, nitrite, aldosterone and vasopressin levels, in addition to the activity of the angiotensin-converting enzyme were also evaluated. Additionally, vascular reactivity to acetylcholine, sodium nitroprusside, and phenylephrine, and the role of nitric oxide, prostaglandins, and K⁺ channels in the vasodilator response of ESCC on the mesenteric vascular bed were also investigated.

RESULTS

ESCC-treatment induced an important cardiorenal protective response, preserving renal function and preventing elevation of blood pressure and heart rate in ovariectomized hypertensive rats. In addition, prolonged treatment with ESCC recovered mesenteric vascular reactivity at all doses used. This effect was associated with an important modulation of the antioxidant defense system with a possible increase in NO bioavailability. Additionally, NO/cGMP activation and K⁺ channel opening-dependent vasodilator effect was observed on the mesenteric vascular bed, indicating a potential mechanism for the cardiovascular effects of ESCC.

CONCLUSION

A 28-days ESCC treatment reduces the progression of the cardiorenal disease in ovariectomized hypertensive rats. These effects seem to be involved with an attenuation of oxidative and nitrosative stress, affecting endothelial nitric oxide production and K⁺ channel opening in smooth muscle cells.

Polyphenol-Rich Extracts from Cotoneaster Leaves Inhibit Pro-Inflammatory Enzymes and Protect Human Plasma Components against Oxidative Stress In Vitro

The present study investigated the phenolic profile and biological activity of dry extracts from leaves of C. bullatus, C. zabelii and C. integerrimus-traditional medicinal and dietary plants-and evaluated their potential in adjunctive therapy of cardiovascular diseases. Complementary UHPLC-PDA-ESI-MS³, HPLC-PDA-fingerprint, Folin-Ciocalteu, and n-butanol/HCl assays of the extracts derived by fractionated extraction confirmed that they are rich in structurally diverse polyphenols (47 analytes, content up to 650.8 mg GAE/g dw) with proanthocyanidins (83.3⁻358.2 mg CYE/g) dominating in C. bullatus and C. zabelii, and flavonoids (53.4⁻147.8 mg/g) in C. integerrimus. In chemical in vitro tests of pro-inflammatory enzymes (lipoxygenase, hyaluronidase) inhibition and antioxidant activity (DPPH, FRAP), the extracts effects were dose-, phenolic- and extraction solvent-dependent. The most promising polyphenolic extracts were demonstrated to be effective antioxidants in a biological model of human blood plasma-at in vivo-relevant levels (1⁻5 µg/mL) they normalized/enhanced the non-enzymatic antioxidant capacity of plasma and effectively prevented peroxynitrite-induced oxidative/nitrative damage of plasma proteins and lipids. As demonstrated in cytotoxicity tests, the extracts were safe-they did not affect viability of human peripheral blood mononuclear cells. In conclusion, Cotoneaster leaves may be useful in development of natural-based products, supporting the treatment of oxidative stress/inflammation-related chronic diseases, including cardiovascular disorders.

Herbal fertility treatments used in North America from colonial times to 1900, and their potential for improving the success rate of assisted reproductive technology

This paper serves to fill a gap in the literature regarding evidence for the use of botanical remedies in the promotion of fertility. It examines the botanical remedies that were used in North America (1492-1900) for all stages of reproduction from preconception to birth, and discusses their potential for future use with present-day infertility treatments. Each medicinal plant discussed in this paper is assessed using an ethnomedicinal methodology that entails examining the published ethnobotanical, phytochemical and pharmacological data. A few clinical trials have shown that there is potential for medicinal plants to improve the success rate of assisted reproductive technology (ART) treatment if used in an integrated manner, similar to the integrated use of traditional Chinese medicine with ART treatment. For example, research has shown that older women who become pregnant have a high miscarriage rate, and this is one area that complementary and alternative medicines can address.

New cyclopentaquinoline hybrids with multifunctional capacities for the treatment of Alzheimer's disease

Alzheimer’s disease (AD) is the most common progressive form of brain neurodegeneration and the most prevailing cause of dementia. Unfortunately, the aetiology of AD is not completely studied but different factors are associated with the development of AD such as among others low level of acetylcholine, aggregation of β-amyloid (Aβ), hyperphosphorylated tau protein, oxidative stress, and inflammation. The study encompass organic syntheses of 2,3-dihydro-1H-cyclopenta[b]quinoline with 5,6-dichloronicotinic acid and suitable linkers derivatives as multifunctional agents for AD treatment. Afterwards self-induced amyloid beta aggregation, inhibition studies of acetylcholinesterase and butyrylcholinesterase and molecular docking studies were performed. The results showed that 3b compound exhibited the best acetylcholinesterase inhibitory activity, with IC₅₀ value of 0.052 µM which is lower compared to references. Besides, all synthesised compounds showed good butyrylcholinesterase inhibitory activity with IC₅₀ values from 0.071 to 0.797 µM. Compound 3b exhibited strong Aβ_1–42 aggregation inhibitory effect with 25.7% at 5 µM to 92.8% at 100 µM as well as good anti-inflammatory effect. Thus, new compounds could create new perspectives for further development as a multi-target-directed agent for AD treatment.

Chemical composition, antioxidant and antibacterial activities of essential oil and methanol extract of Artemisia vulgaris and Gaultheria fragrantissima collected from Nepal

OBJECTIVE

To identify the chemical constituents and biological activities of essential oil and crude methanol extract of Artemisia vulgaris (A. vulgaris) and Gaultheria fragrantissima (G. fragrantissima).

METHODS

Phytochemical screening, total phenolic and flavonoid content, antibacterial activities, anti-oxidant assay of the crude extract were carried out to identify the biological activities and phytonutrients present in the extract. Furthermore, the chemical constituents present in the essential oil and crude methanol extract were analyzed using gas chromatography mass spectroscopy and high performance liquid chromatography (HPLC) analysis.

RESULTS

Gas chromatography mass spectroscopy analysis of essential oil from the aerial part of A. vulgaris revealed 24 different compounds in it. Sabinene (11.29%), β-thujone (19.19%), chrysanthenone (4.48%), camphor (11.89%), borneol (4.44%) and germacrene D (8.42%) were the major compounds. Similarly, leaves of G. fragrantissima contained methyl salicylate (95%) and asarone (4.64%). Furthermore, methanol extract of leaves of A. vulgaris and G. fragrantissima were found rich in the total flavonoids and phenolic content. HPLC analysis of the methanol extract of leaves A. vulgaris revealed the presence of morin and luteolin, whereas rutin was found as a major flavonoids compound in the leaves of G. fragrantissima. Further, methanol extract of the A. vulgaris and G. fragrantissima showed the highest antioxidant and antibacterial properties compared to the essential oil.

CONCLUSIONS

The HPLC analysis of the methanol extract of A. vulgaris shows the presence of luteolin and morin, whereas G. fragrantissima reveals the presence of rutin and a glycosylated flavonoids. Results reveal that A. vulgaris oil is the rich source of monoterpene and sesquiterpene compounds. Furthermore, A. vulgaris and G. fragrantissima are the rich source of the phenolic and flavonoids compounds and show good antioxidant and antibacterial activity.

Metabolite Profiling of Eastern Teaberry (Gaultheria procumbens L.) Lipophilic Leaf Extracts with Hyaluronidase and Lipoxygenase Inhibitory Activity

The phytochemical profile and anti-inflammatory activity of Gaultheria procumbens dry lipophilic leaf extracts were evaluated. Forty compounds were identified by GC-MS, representing 86.36% and 81.97% of the petroleum ether (PE) and chloroform (CHE) extracts, respectively, with ursolic acid (28.82%), oleanolic acid (10.11%), methyl benzoate (10.03%), and methyl salicylate (6.88%) dominating in CHE, and methyl benzoate (21.59%), docosane (18.86%), and octacosane (11.72%) prevailing in PE. Three components of CHE were fully identified after flash chromatography isolation and spectroscopic studies as (6S,9R)-vomifoliol (4.35%), 8-demethyl-latifolin (1.13%), and 8-demethylsideroxylin (2.25%). Hyaluronidase and lipoxygenase inhibitory activity was tested for CHE (IC50 = 282.15 ± 10.38 μg/mL and 899.97 ± 31.17 μg/mL, respectively), PE (IC50 = 401.82 ± 16.12 μg/mL and 738.49 ± 15.92 μg/mL), and nine of the main constituents versus heparin (IC50 = 366.24 ± 14.72 μg/mL) and indomethacin (IC50 = 92.60 ± 3.71 μg/mL) as positive controls. With the best activity/concentration relationships, ursolic and oleanolic acids were recommended as analytical markers for the extracts and plant material. Seasonal variation of both markers following foliar development was investigated by UHPLC-PDA. The highest levels of ursolic (5.36-5.87 mg/g DW of the leaves) and oleanolic (1.14-1.26 mg/g DW) acids were observed between August and October, indicating the optimal season for harvesting.

Stabilization of anthocyanins in blackberry juice by glutathione fortification

Blackberry anthocyanins provide attractive color and antioxidant activity.

Agrimonia eupatoria L. and Cynara cardunculus L. Water Infusions: Phenolic Profile and Comparison of Antioxidant Activities

Reactive oxygen species (ROS) are highly considered in the ethiopathogenesis of different pathological conditions because they may cause significant damage to cells and tissues. In this paper, we focused on potential antioxidant properties of two medical plants such as the Agrimonia eupatoria L. and Cynara cardunculus L. Both plants have previously been studied for their pharmacological activities, especially as hepatoprotective and hypoglycemic activities. It has been suggested, that their effects are related to the antioxidant properties of polyphenols, which are dominant compounds of the plants’ extracts. In the present study HPLC-MS analysis of water infusion was performed allowing the identification of several phenolic constituents. Furthermore, antioxidant effects of the two extracts were compared showing higher effects for agrimony extract compared to artichoke. Thus, agrimony was selected for the in vivo study using the skin flap viability model. In conclusion, our results provide evidence that the A. eupatoria extract may be a valuable source of polyphenols to be studied for the future development of supplements useful in the prevention of diseases linked to oxidative stress.

Antioxidant activity and anti-inflammatory activity of ethanol extract and fractions of Doenjang in LPS-stimulated RAW 264.7 macrophages

BACKGROUND/OBJECTIVES

Fermentation can increase functional compounds in fermented soybean products, thereby improving antioxidant and/or anti-inflammatory activities. We investigated the changes in the contents of phenolics and isoflavones, antioxidant activity and anti-inflammatory activity of Doenjang during fermentation and aging.

MATERIALS/METHODS

Doenjang was made by inoculating Aspergillus oryzae and Bacillus licheniformis in soybeans, fermenting and aging for 1, 3, 6, 8, and 12 months (D1, D3, D6, D8, and D12). Doenjang was extracted using ethanol, and sequentially fractioned by hexane, dichloromethane (DM), ethylacetate (EA), n-butanol, and water. The contents of total phenolics, flavonoids and isoflavones, 2,2-diphenyl-1 picryl hydrazyl (DPPH) radical scavenging activity, and ferric reducing antioxidant power (FRAP) were measured. Anti-inflammatory effects in terms of nitric oxide (NO), prostaglandin (PG) E2 and pro-inflammatory cytokine production and inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 expressions were also measured using LPS-treated RAW 264.7 macrophages.

RESULTS

Total phenolic and flavonoid contents showed a gradual increase during fermentation and 6 months of aging and were sustained thereafter. DPPH radical scavenging activity and FRAP were increased by fermentation. FRAP was further increased by aging, but DPPH radical scavenging activity was not. Total isoflavone and glycoside contents decreased during fermentation and the aging process, while aglycone content and its proportion increased up to 3 or 6 months of aging and then showed a slow decrease. DM and EA fractions of Doenjang showed much higher total phenolic and flavonoid contents, and DPPH radical scavenging activity than the others. At 100 µg/mL, DM and EA fractions of D12 showed strongly suppressed NO production to 55.6% and 52.5% of control, respectively, and PGE2 production to 25.0% and 28.3% of control with inhibition of iNOS or COX-2 protein expression in macrophages.

CONCLUSIONS

Twelve month-aged Doenjang has potent antioxidant and anti-inflammatory activities with high levels of phenolics and isoflavone aglycones, and can be used as a beneficial food for human health.