Ellagic Acid Derivatives Research Articles

Nutritional Composition, Phytochemical Profile, Extraction Methods of Bioactive Components, and Health Benefits of Terminalia Arjuna Bark

ABSTRACTTerminalia arjuna, known as Arjuna, is a medicinal plant native to the Indian subcontinent. It has a rich history of traditional use and contains a wide range of phytoconstituents that contribute to its potential health benefits. The key phytoconstituents in Terminalia arjuna include polyphenols, triterpenoids, flavonoids, and tannins. The plant's bark is rich in polyphenols, particularly gallic acid and ellagic acid derivatives, which are powerful antioxidants. These antioxidants can protect cells from oxidative stress and may help prevent degenerative diseases. Additionally, Terminalia arjuna contains triterpenoids like arjunolic acid and arjunic acid, which have various therapeutic properties, including cardioprotective, anti‐allergic, anti‐cancer, and antibacterial effects. Flavonoids found in Terminalia arjuna, such as luteolin and quercetin, contribute to its potential cardiovascular benefits. These compounds have been studied for their positive effects on heart health. Tannins, including pyrocatechols and punicalagin, are also present in the bark and are known for their astringent properties, wound‐healing abilities, and possible antimicrobial activity. This review highlights the Terminalia arjuna potential health benefits include cardioprotection, antioxidant effects, anti‐inflammatory and analgesic properties, hypolipidemic (lipid‐lowering) effects, and potential anti‐cancer and antibacterial actions.

Clarification of morphological traits of unexplored 'Mortarella' and 'Camponica' hazelnut cvs. From the Campania region of Italy, to enhance their shell polyphenol diversity.

Clarification of morphological traits of unexplored 'Mortarella' and 'Camponica' hazelnut cvs. From the Campania region of Italy, to enhance their shell polyphenol diversity.

Antiparasitic Activities of Plants From the Traditional Senegalese Pharmacopoeia: Isolation of Antitrypanosomal and Antileishmanial Ellagic Acid Derivatives From Terminalia Avicennioides.

Parasitic diseases such as trypanosomiasis and leishmaniasis pose significant health challenges in Africa. The Senegalese Pharmacopoeia, known for its many medicinal plants with anti-infectious properties, can be a source of antiparasitic natural products. This study aimed to evaluate the in vitro antiparasitic activities of 33 methanolic extracts from 24 ethnopharmacologically selected plants against Trypanosoma brucei brucei (Tbb) and Leishmania mexicana mexicana (Lmm), as well as their cytotoxic activities on WI-38 cells. The most promising plant species were Balanites aegyptiaca, Eucalyptus camaldulensis, Vachellia nilotica and four Combretaceae species. In a second step, antitrypanosomal and antileishmanial compounds were isolated by preparative high-performance liquid chromatography from one of the most active plant extracts, Terminalia avicennioides leaves. Four ellagic acid derivatives were identified by nuclear magnetic resonance (1D & 2D) and high-resolution electrospray ionization-tandem mass spectrometry (HR-ESI-MS/MS) as 3,4,3-tri-O-methylellagic acid (2), 3,4,5-O-trimethyl-3',4'-O,O-methylideneflavellagic acid (3), hexamethylcoruleoellagic acid (4) and pentamethylflavellagic acid (5). In addition, HR-ESI-MS/MS-based dereplication analysis was performed to putatively identify compounds in active cyclohexane and dichloromethane sub-extracts. Pentamethylflavellagic acid (5) showed the most promising activity against Tbb (half-maximal inhibitory concentration = 6.20 µM). This is the first time that these compounds have been isolated from T. avicennioides and evaluated for their antitrypanosomal and antileishmanial activities.

Influence of altitudes and development stages on the chemical composition and antioxidant capacity of Andean blackberries (Rubus glaucus Benth).

The Andean blackberry (Rubus glaucus Benth), locally known as "Mora de Castilla," is a high-altitude fruit rich in phytochemicals, mainly anthocyanins, with potent antioxidant properties. Although its chemical composition has been studied, the influence of altitude on its phytochemical profile and antioxidant capacity is still unclear. This research aimed to investigate the effects of development stages and altitude on the phytochemical profile and antioxidant activity of this fruit. Andean blackberry fruits were collected at different altitudes and development stages in the central Andean region of Ecuador. An hydroalcoholic extraction was used to quantify the compounds and determine the total antioxidant activity, while solid phase extraction (SPE) was performed to separate anthocyanins from other compounds. Ultra-high-performance liquid chromatography coupled to a triple quadrupole mass spectrometer (HPLC-DAD/ESI-MSn) was used to identify anthocyanin and non-anthocyanin phenols, while total antioxidant capacity, total polyphenols, total flavonoid content, and total anthocyanin content were quantified spectrophotometrically. Flavonols and anthocyanins constitute the majority of the flavonoids identified in the Andean blackberry extracts, both in terms of peak areas and number of identified compounds, followed by ellagic and gallic acid derivatives, as well as phenolic acids, mainly hydroxycinnamic acids. Quercetin was identified as the predominant flavonol in unripe berries, where anthocyanins were not significantly present. On the contrary, in ripe berries, cyanidin and its glycosides stood out as the main anthocyanins and predominant compounds. We observed that in the early stages of ripening, the total polyphenol content predominates in the berries and is mainly responsible for their antioxidant capacity. However, as the fruit ripens, the total anthocyanin content increases, becoming the most prominent bioactive compounds in fully ripe berries. The results suggest that higher altitude environmental conditions may improve the composition, concentration of phenolic compounds, and antioxidant activity of Andean blackberries. Overall, our findings highlight the high functional value of this fruit, supporting its health-protective effects when consumed regularly, either as fresh fruit or in nutraceutical form.

METABOLÓMICA DE POLYLEPIS RACEMOSA Y UTILIZACIÓN DEL EXTRATO ACUOSO DE SU TALLO EN LA SÍSTESIS DE NANOPARTÍCULAS DE PLATA

The green synthesis of silver nanoparticles (AgNPs) by the action of extracts of plant species has a promising future due to its multiple applications. In this work, we prepare AgNPs with an aqueous extract of Polylepis racemosa rhytidomes, a typical South American plant species whose phytochemistry has been little studied. The metabolomic study of this extract by UHPLC-MS allowed us to identify some organic acids, N-acetylglutamic acid, two glycosylated derivatives of ellagic acid (one of them is a new compound) and three glycosylated triterpenes. Aqueous extracts of Polylepis racemosa rhytidome with extraction times of 2, 6, 12 and 30 minutes were used for the synthesis of AgNPs. By SEM it was observed that the size of the AgNPs was approximately 12 nm, obtained with extracts of 2, 6 and 12 minutes. Finally, by comparing the scans by UHPLC-MS before and after the synthesis of AgNPs, and by the characteristics of the metabolites present, it is deduced that the organic acids of the extract stabilized the nanoparticles generated by the reducing groups present. It is concluded that the extract extraction time is an important study variable in the green synthesis of AgNPs with Polylepis racemosa rhytidome.

Animal pollination shapes fruits market features, seeds functional traits and modulates their chemistry

In this study, we experimentally addressed the impact of different pollination treatments on the morphological, reproductive and chemical traits of fruits and seeds of two crop species, the wild strawberry (Fragaria vesca L.) and cowpea (Vigna unguiculata (L.) Walp.). Multiple flowers from each plant were exposed to different pollination treatments: (1) self pollination, (2) hand cross pollination and (3) open pollination. Both crops were positively affected by open pollination in terms of morpho-chemical parameters concerning the marketability (e.g., 35% decrease in sugar/acid ratio in open pollinated strawberries compared to the autogamous ones) and the seed germination rate as a proxy of reproduction efficiency (e.g., the almost complete absence of seed abortion in the open pollination treatment). Remarkably, the pollination treatment also strongly influenced the phytochemical composition. Open-pollinated strawberries exhibited a higher relative concentration of compounds endowed with nutraceutical properties such as anthocyanins, ellagic acid derivatives and flavonoids. At the same time, cowpea seeds displayed higher concentrations of anti-nutrients in the self pollination treatments, such as saponins, compared to the open and hand cross pollinated seeds. This study suggests the presence of a link between the pollination mechanism, market quality, plant reproduction and chemical properties of fruits and seeds, supporting the intricate interplay between pollinators, plants and human nutrition, highlighting the crucial importance of animal pollination in the ecological and dietary contexts.

A Systematic Review of Medicinal Plants and Their Compounds Validated as Agents for the Management of Sickle Cell Disease

Some plants used in traditional medicine to manage sickle cell disease have been validated pharmacologically to ascertain their anti-sickling properties. However, there is no global systematic review of the evidence in support of their use for sickle cell management. This research aimed to conduct a systematic review of the pharmacological evidence to highlight species, genera, and some phytochemicals which could be primed for novel anti-sickling medications. The Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines were used. Articles in English, published from 2000 to 2022 were included in the analysis. The literature search covered 411 publications of which 82 were found to be eligible. More than half (53.65%) of the articles were published from 2016 to 2022. Anti-sickling research from Africa accounted for 86.58% of the publications, with more than half coming from Nigeria, 12.20% from Asia and only 1.22% from Europe. The Fabaceae, Euphorbiaceae, and Annonaceae were the top three plant families whereas Zanthoxylum and Terminalia were the most reported genera. Carica papaya and Terminalia catappa were the most reported species. Sickling reversal ( n = 33/82) and hemoglobin polymerization studies ( n = 29/82) were the most reported assays. Benzoic acid derivatives, butyl stearate, ellagic acid derivatives, and some pentacyclic triterpenoids were the only plant derived compounds validated for anti-sickling activities. A total of 117 plant species with anti-sickling activities were documented. Studies on secondary metabolites with anti-sickling properties to serve as scaffolds for novel drug development for sickle cell management were limited.

Phytochemical composition of wild pomegranate juices and their cytotoxicity

PurposeThis study aims to examine the relationship between the chemical composition of juices obtained from fruits of autochthonous wild pomegranate (Punica granatum L.) grown in Montenegro and their cytotoxic effects on cancer cells.Design/methodology/approachTo explore the potential value of wild pomegranate fruits, in vitro biological assays were carried out with juices whose composition was analyzed in detail for sugars, organic acids, vitamin C and phenolic compounds. The effect of juices on survival was determined in human lung A549, cervical HeLa and breast MCF-7 carcinoma cells by MTT assay. As a control, the cytotoxicity against normal fetal lung fibroblasts (MRC-5) was monitored.FindingsAmong cancer cell lines, considering the IC50 related to total phenolics, the lowest value – 13 µg/mL was found for the A549. The strongest effect on lung cells was assumed due to the favorable contribution of ellagitannins to total phenolics in juice as well as the given combination of anthocyanins and their synergistic action. For HeLa cells, the lowest IC50 value was obtained at 88 µg/mL, and the cytotoxicity could be matched with the effects of anthocyanins and catechin. For MCF-7 cells, the lowest IC50 was 504 µg/mL, and the elevated levels of vitamin C and ellagic acid derivatives should have a noticeable effect on these cells.Originality/valueThis study provides an important contribution to the knowledge on the effect of phytochemicals from wild pomegranate juice on lung, cervical and breast cancer cells, in vitro. The present observations suggest that the juice of wild pomegranate has the potential in the fight against cancer.

In Vitro and Molecular Docking Evaluation of the Anticholinesterase and Antidiabetic Effects of Compounds from Terminalia macroptera Guill. & Perr. (Combretaceae).

Alzheimer's disease (AD) and diabetes are non-communicable diseases with global impacts. Inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are suitable therapies for AD, while α-amylase and α-glucosidase inhibitors are employed as antidiabetic agents. Compounds were isolated from the medicinal plant Terminalia macroptera and evaluated for their AChE, BChE, α-amylase, and α-glucosidase inhibitions. From 1H and 13C NMR data, the compounds were identified as 3,3'-di-O-methyl ellagic acid (1), 3,3',4'-tri-O-methyl ellagic acid-4-O-β-D-xylopyranoside (2), 3,3',4'-tri-O-methyl ellagic acid-4-O-β-D-glucopyranoside (3), 3,3'-di-O-methyl ellagic acid-4-O-β-D-glucopyranoside (4), myricetin-3-O-rhamnoside (5), shikimic acid (6), arjungenin (7), terminolic acid (8), 24-deoxysericoside (9), arjunglucoside I (10), and chebuloside II (11). The derivatives of ellagic acid (1-4) showed moderate to good inhibition of cholinesterases, with the most potent being 3,3'-di-O-methyl ellagic acid, with IC50 values of 46.77 ± 0.90 µg/mL and 50.48 ± 1.10 µg/mL against AChE and BChE, respectively. The compounds exhibited potential inhibition of α-amylase and α-glucosidase, especially the phenolic compounds (1-5). Myricetin-3-O-rhamnoside had the highest α-amylase inhibition with an IC50 value of 65.17 ± 0.43 µg/mL compared to acarbose with an IC50 value of 32.25 ± 0.36 µg/mL. Two compounds, 3,3'-di-O-methyl ellagic acid (IC50 = 74.18 ± 0.29 µg/mL) and myricetin-3-O-rhamnoside (IC50 = 69.02 ± 0.65 µg/mL), were more active than the standard acarbose (IC50 = 87.70 ± 0.68 µg/mL) in the α-glucosidase assay. For α-glucosidase and α-amylase, the molecular docking results for 1-11 reveal that these compounds may fit well into the binding sites of the target enzymes, establishing stable complexes with negative binding energies in the range of -4.03 to -10.20 kcalmol-1. Though not all the compounds showed binding affinities with cholinesterases, some had negative binding energies, indicating that the inhibition was thermodynamically favorable.

Extraction of bioactive compounds from pecan nutshell: An added-value and low-cost alternative for an industrial waste

Extraction of bioactive compounds from pecan nutshell: An added-value and low-cost alternative for an industrial waste

Development of a New Extraction Method for Pomegranate and Metabolite Profiling by a LC-MS and 1H NMR Combined Approach.

The pomegranate (Punica granatum L.) market has steadily grown due to the increasing demand of health-conscious consumers of products with health-promoting effects. Recently, a growing interest in developing ecological and environmentally friendly extraction methods has led to investigating extraction procedures to obtain a higher extraction yield using a lower amount of solvents and energy. Herein, a new extraction procedure was developed to obtain an enriched pomegranate food supplement by using the peels of pomegranate, cultivar "Dente di Cavallo" and its juice. The extraction was performed through a non-conventional extraction technique like SLDE-Naviglio using ethanol and pomegranate juice as a solvent, and peels as a matrix. The extract was analysed by a combined approach based on LCESI/QExactive/MS/MS and NMR analysis, and its chemical profile was compared with those of pomegranate juice and of the extract obtained from peels by SLDE-Naviglio by using ethanol:H2O. The LC-MS analysis highlighted the presence of hydrolysable tannins, flavonoids, ellagic acid and phenol glucoside derivatives, while 1H NMR analysis completed the profile by detecting the primary metabolites. The LC-MS and 1H NMR analysis indicated that the extract obtained by SLDE-Naviglio using ethanol and pomegranate juice was enriched in the bioactives as confirmed by the highest phenolic, tannin and flavonoid content.

Heterogeneity of transport and metabolism of Tormentillae rhizoma constituents across human intestinal epithelium cellular model

Tormentilla erecta (L.) Raeusch is a widespread plant in Europe and Western Asia. Its rhizomes (Tormentilae rhizoma) are the main ingredient of herbal alcoholic beverages and can be used as a natural preservative in beer production. Apart from its unique taste qualities, therapeutic properties in gastrointestinal tract ailments are attributed to the tincture obtained from Tormentillae rhizoma. The presented research aimed to determine the mutual relationship between the components of Tormentillae tincture, present in popular alcoholic beverages, and intestinal epithelium (Caco-2 cell monolayers). A comprehensive qualitative and quantitative analysis of the tincture was performed, including the determination of condensed and hydrolyzable tannins as well as triterpenoids (UHPLC-DAD-MS/MS). Incubation of the tincture with Caco-2 monolayers has shown that only triterpenes pass through the monolayer, while condensed tannins are mainly bound to the monolayer surface. Ellagic acid derivatives were the only components of the Tormentillae tinctura being metabolized by cell monolayers to the compounds not previously described in the literature, which may be crucial in the treatment of intestinal diseases with inflammatory background.

A Monocarbonyl Curcuminoid Derivative Inhibits the Activity of Human Glutathione Transferase A4-4 and Chemosensitizes Glioblastoma Cells to Temozolomide.

Human glutathione transferase A4-4 (hGSTA4-4) displays high catalytic efficiency towards 4-hydroxyalkenals and other cytotoxic and mutagenic products of radical reactions and lipid peroxidation. Its role as a target for the chemosensitization of cancer cells has not been investigated so far. In this study, the inhibitory potency of twelve selected natural products and ten monocarbonyl curcumin derivatives against hGSTA4-4 was studied. Among natural products, ellagic acid turned out to be the strongest inhibitor with an IC50 value of 0.44 ± 0.01 μM. Kinetic analysis using glutathione (GSH) and 1-chloro-2,4-dinitrobenzene (CDNB) as variable substrates showed that ellagic acid behaved as a competitive inhibitor towards both GSH and CDNB, with Ki values of 0.39 ± 0.02 and 0.63 ± 0.03 μM, respectively. Among the curcumin derivatives studied, three proved to be the most potent inhibitors, in the order DM151 > DM101 > DM100, with IC50 values of 2.4 ± 0.1 μM, 12.7 ± 1.1 μΜ and 16.9 ± 0.4 μΜ, respectively. Further kinetic inhibition analysis of the most active derivative, DM151, demonstrated that this compound is a mixed inhibitor towards CDNB with inhibition constants of Ki = 4.1 ± 0.5 μM and Ki' = 0.536 ± 0.034 μM, while it is a competitive inhibitor towards GSH with a Ki = 0.98 ± 0.11 μM. Molecular docking studies were performed to interpret the differences in binding of ellagic acid and curcumin derivatives to hGSTA4-4. The in silico measured docking scores were consistent with the obtained experimental data. Hydrogen bonds appear to be the main contributors to the specific binding of monocarbonyl curcumin derivatives, while π-π stacking interactions play a key role in the enzyme-ellagic acid interaction. In vitro cytotoxicity assessment of the worst (DM148) and the best (DM151) inhibitors was performed against glioblastoma cell lines U-251 MG and U-87 MG. The results revealed that DM151 displays considerably higher cytotoxicity against both glioblastoma cell lines, while the glioblastoma cytotoxicity of DM148 was very limited. Furthermore, low and non-toxic doses of DM151 sensitized U-251 MG cells to the first-line glioblastoma chemotherapeutic temozolomide (TMZ), allowing us to propose for the first time that hGSTA4-4 inhibitors may be attractive therapeutic partners for TMZ to optimize its clinical effect in glioblastoma chemotherapy.

Phenolic composition and bioactivities of sea buckthorn (Hippophae rhamnoides L.) fruit and seeds: an unconventional source of natural antioxidants in North America.

Sea buckthorn (Hippophae rhamnoides L.) was introduced into Canada in the early 2000s. This plant bears fruits with high commercial value in other countries due to its premium oil. Nevertheless, sea buckthorn berries are also a rich source of bioactives with nutraceutical potential, especially the variety grown in Newfoundland (Canada), which has not previously been characterized. As such, this study evaluated the composition of polyphenols in sea buckthorn pomace and seeds, as well as their prospective health-promoting effects. Polyphenolic identification by high-performance liquid chromatography-ultraviolet-mass spectrometry-time of flight revealed the presence of 24 compounds in the seeds and 16 compounds in the pomace, including phenolic acids, flavonoids, and tannins, with ellagic acid derivative IV (pomace, 52.13 μg g-1) and (+)-catechin (seeds, 690.8 μg g-1) being the most dominant. Sea buckthorn extracts displayed in vitro antidiabetic and anti-obesity potential by inhibiting α-glucosidase (71.52-99.31%) and pancreatic lipase (15.80-35.61%) enzymes, respectively. The extracts also protected low-density-lipoprotein cholesterol (50.97-89.67%) and supercoiled DNA (35.11-79.84%) from oxidative damage. Sea buckthorn berries grown in Canada showed promising health benefits induced by their rich and diverse polyphenolic profile and need to be considered for further commercial expansion as a bioactive-loaded superfruit. © 2024 Society of Chemical Industry.

'Sorrento' and 'Tulare' Walnut Cultivars: Morphological Traits and Phytochemical Enhancement of Their Shell Waste.

Walnut processing generates considerable quantities of by-products that could be reprocessed into value-added products that have food and non-food applications. In this context, the aim of this study is to characterize the 'Sorrento' and 'Tulare' walnut cultivars using the UPOV guidelines and analyze the chemical composition and antioxidant activity of their shells. Insight into the chemical composition of the different granulometric fractions of walnut shell, obtained by sieving, was obtained following ultrasound-assisted extraction by Ultra-High-Performance Liquid Chromatography-High-Resolution Mass Spectrometry (UHPLC-HRMS). The total phenolic, flavonoid, and tannin content and antiradical capacity, obtained by DPPH and ABTS assays, and the Fe(III) reducing power of the extracts were also evaluated. The UHPLC-HRMS analysis indicated the presence of thirty-two compounds ascribable to four major classes of specialized metabolites. Furthermore, the extraction efficiency of gallic acid, ellagic acid derivatives, as well as glansreginin A, increased with the decrease in shell matrix particle size in contrast to chlorogenic acids and flavonoid glycosides. This is the first study to highlight new knowledge on the chemical composition of walnut shells. The results obtained demonstrate the feasibility of recovering valuable bioactive components from agro-waste that may be further valorized.

A Biostimulant Based on Silicon Chelates Enhances Growth and Modulates Physiological Responses of In-Vitro-Derived Strawberry Plants to In Vivo Conditions.

The purpose was to assess the effects of a biostimulant based on silicon chelates in terms of alleviation of the impact of in vivo conditions on strawberry (Fragaria × ananassa cv. 'Solnechnaya polyanka') in-vitro-derived plants. As a source of silicon chelates, a mechanocomposite (MC) obtained through mechanochemical processing of rice husks and green tea was used. Root treatment of plants with 0.3 g L-1 of MC dissolved in tap water was performed at 2 weeks after planting. Control plants were watered with tap water. The greatest shoot height, number of roots per plant, root length, number of stolons per plant, daughter ramets per stolon, relative water content, cuticle thickness, and root and shoot biomasses were achieved with the MC supplementation. The improved parameters were associated with a higher silicon content of roots and shoots of the MC-treated plants. Leaf concentrations of hydrogen peroxide and abscisic acid were reduced by the MC. This effect was accompanied by enhanced activity of superoxide dismutase and catalase. The phenolic profile showed upregulation of p-hydroxybenzoic acid, vanillic acid, gallic acid, syringic acid, and ellagic acid derivative 2, while kaempferol rutinoside and catechins were downregulated. Thus, silicon chelates improve growth and trigger the physiological processes that enhance free-radical-scavenging activity in strawberry plants in vivo.

In Silico Screening of Ellagic Acid Derivatives and Their Metabolites as Inhibitors for NF-?b and Tnf?

The aim of this study was to evaluate inhibitory effects of ellagic acid derivatives and their metabolites on tumor necrosis factor ? (TNF?) and nuclear factor-?B (NF-?B). In silico molecular docking was performed. 3-O-methyl-3', 4' -methylenedioxy ellagic acid (MMDEA) and urolithin D were to be potent inhibitors of TNF? among tested molecules. For NF-?B (p50 and p65 subunits), MMDEA was found to be a potent inhibitor comparable with tanshinone IIA, a known NF-?B inhibitor. Ellagic acid derivatives seemed to be more effective than urolithins, their metabolites. All of the ellagic acid derivatives and their metabolites were predicted to have good pharmacokinetical properties according to Lipinski's rule of five. These results suggest that ellagic acid derivatives may potentially down-regulate inflammatory responses..

Medicinal plant Miconia albicans synergizes with ampicillin and ciprofloxacin against multi-drug resistant Acinetobacter baumannii and Staphylococcus aureus

BackgroundGiven the rising occurrence of antibiotic resistance due to the existence and ongoing development of resistant bacteria and phenotypes, the identification of new treatments and sources of antimicrobial agents is of utmost urgency. An important strategy for tackling bacterial resistance involves the utilization of drug combinations, and natural products derived from plants hold significant potential as a rich source of bioactive compounds that can act as effective adjuvants. This study, therefore, aimed to assess the antibacterial potential and the chemical composition of Miconia albicans, a Brazilian medicinal plant used to treat various diseases.MethodsEthanolic extracts from leaves and stems of M. albicans were obtained and subsequently partitioned to give the corresponding hexane, chloroform, ethyl acetate, and hydromethanolic phases. All extracts and phases had their chemical constitution investigated by HPLC–DAD-MS/MS and GC–MS and were assessed for their antibiofilm and antimicrobial efficacy against Staphylococcus aureus. Furthermore, their individual effects and synergistic potential in combination with antibiotics were examined against clinical strains of both S. aureus and Acinetobacter baumannii. In addition, 10 isolated compounds were obtained from the leaves phases and used for confirmation of the chemical profiles and for antibacterial assays.ResultsBased on the chemical profile analysis, 32 compounds were successfully or tentatively identified, including gallic and ellagic acid derivatives, flavonol glycosides, triterpenes and pheophorbides. Extracts and phases obtained from the medicinal plant M. albicans demonstrated synergistic effects when combined with the commercial antibiotics ampicillin and ciprofloxacin, against multi-drug resistant bacteria S. aureus and A. baumannii, restoring their antibacterial efficacy. Extracts and phases also exhibited antibiofilm property against S. aureus. Three key compounds commonly found in the samples, namely gallic acid, quercitrin, and corosolic acid, did not exhibit significant antibacterial activity when assessed individually or in combination with antibiotics against clinical bacterial strains.ConclusionsOur findings reveal that M. albicans exhibits remarkable adjuvant potential for enhancing the effectiveness of antimicrobial drugs against resistant bacteria.

Chemical constituents from Potentilla kleiniana and their chemotaxonomic significance

Chemical constituents from Potentilla kleiniana and their chemotaxonomic significance

Inhibition of pro-inflammatory cytokines by selected southern African medicinal plants in LPS-stimulated RAW 264.7 macrophages

Ethnopharmacological relevanceBark is frequently used in southern African traditional medicine to treat inflammation, yet it remains to be rigorously examined for its immunological and anti-inflammatory activity. Aim of the studyBarks obtained from ten important and popular southern Africa plants were evaluated for their anti-inflammatory and immunomodulatory properties against the secretion of some pro-inflammatory cytokines (interleukin (IL)-1β, IL-6, tumour necrosis factor-α (TNF-α), and interferon-gamma (IFN-γ) as well as chemokines (monocyte chemoattractant protein 1 (MCP-1) and macrophage inflammatory protein (MIP)-2) in murine RAW 264.7 macrophages. Materials and methodsThe inhibitory effects of aqueous and ethanol extracts were determined using cytokine multiplex-bead assays in lipopolysaccharide (LPS)-stimulated and unstimulated RAW 264.7 cells. ResultsOverall, the ethanol extracts were more potent cytokine inhibitors compared to the aqueous extracts. The LPS-stimulated cells treated with the ethanol extracts of Erythrina lysistemon Hutch., Pterocelastrus rostratus Walp. Syzygium cordatum Hochst. ex Krauss and Warburgia salutaris (G. Bertol.) Chiov., demonstrated significant (p < 0.005) inhibition up to 85% of IL-1β, IL-6, and TNF-α secretion compared to the LPS control. Additionally, P. rostratus and S. cordatum aqueous bark extracts substantially decreased the secretion of all the tested cytokines and chemokines. Chemical investigation of the S. cordatum extract resulted in the identification of four ellagic acid derivatives: ellagic acid 4-O-α-rhamnopyranoside (1), ellagic acid 4-O-α-4″-acetylrhamnopyranoside (2), 3-O-methylellagic acid 4′-O-α-3″-O-acetylrhamnopyranoside (3) and 3-O-methylellagic acid 4′-O-α-4″-O-acetylrhamnopyranoside (4), along with mixtures of ellagic acid 4-O-α-2″-acetylrhamnopyranoside (5), ellagic acid 4-O-α-3″-acetylrhamnopyranoside (6) and ellagic acid (7). Their structures were confirmed by mass spectrometry, NMR spectroscopy, and comparison with data from literature. ConclusionThe cytokine inhibition properties of most of the medicinal plants screened herein are reported for the first time. Our results provide insights into the mechanism of action by which the selected southern African medicinal plants regulate inflammation.