Onion (Allium cepa L.) Skin Waste Valorization: Unveiling the Phenolic Profile and Biological Potential for the Creation of Bioactive Agents through Subcritical Water Extraction.

Onion skin waste (OSW), the primary non-edible byproduct from onion processing, offers a renewable source of bioactive compounds. This study aims to valorize OSW through subcritical water extraction (SWE), aligning with a circular economy and biorefinery principles. SWE was carried out at 145 °C and 50 bar for 50 min in a discontinuous reactor, producing a phenolic-rich extract (32.3 ± 2.6 mg/g) dominated by protocatechuic acid (20.3 ± 2.5 mg/g), quercetin-4'-O-glucoside (7.5 ± 0.2 mg/g), and quercetin (3.2 ± 0.6 mg/g). Additionally, the extract contains sugars (207.1 ± 20.3 mg sucrose-Eq/g), proteins (22.8 ± 1.6 mg BSA-Eq/g), and free amino acids (20.4 ± 1.2 mg arginine-Eq/g). Its phenolic richness determines its scavenging activity against ●NO and O2●- radicals and its α-glucosidase and aldose-reductase inhibition without affecting α-amylase. Notably, the extract demonstrates significant α-glucosidase inhibition (IC50 = 75.6 ± 43.5 µg/mL), surpassing acarbose (IC50 = 129.5 ± 1.0 µg/mL) in both pure enzyme and cell culture tests without showing cytotoxicity to AGS, HepG2, and Caco-2 human cell lines. The extract's bioactivity and nutritional content make it suitable for developing antioxidant and antidiabetic nutraceutical/food components, highlighting SWE's potential for OSW valorization without using organic solvents.

Anti-inflammatory effects of naringenin 8-sulphonate from Parinari excelsa Sabine stem bark and its semi-synthetic derivatives.

The inflammatory response is a vital mechanism for repairing damage induced by aberrant health states or external insults; however, persistent activation can be linked to numerous chronic diseases. The nuclear factor kappa ß (NF-κB) inflammatory pathway and its associated mediators have emerged as critical targets for therapeutic interventions aimed at modulating inflammation, necessitating ongoing drug development. Previous studies have reported the inhibitory effect of a hydroethanol extract derived from Parinari excelsa Sabine (Chrysobalanaceae) on tumour necrosis factor-alpha (TNF-α), but the phytoconstituents and mechanisms of action remained elusive. The primary objective of this study was to elucidate the phytochemical composition of P. excelsa stem bark and its role in the mechanisms underpinning its biological activity. Two compounds were detected via HPLC-DAD-ESI(Ion Trap)-MS2 analysis. The predominant compound was isolated and identified as naringenin-8-sulphonate (1), while the identity of the second compound (compound 2) could not be determined. Both compound 1 and the extract were assessed for anti-inflammatory properties using a cell-based inflammation model, in which THP-1-derived macrophages were stimulated with LPS to examine the treatments' effects on various stages of the NF-κB pathway. Compound 1, whose biological activity is reported here for the first time, demonstrated inhibition of NF-κB activity, reduction in interleukin 6 (IL-6), TNF-α, and interleukin 1 beta (IL-1ß) production, as well as a decrease in p65 nuclear translocation in THP-1 cells, thus highlighting the potential role of sulphur substituents in the activity of naringenin (3). To explore the influence of sulphation on the anti-inflammatory properties of naringenin derivatives, we synthesized naringenin-4'-O-sulphate (4) and naringenin-7-O-sulphate (5) and evaluated their anti-inflammatory effects. Naringenin derivatives 4 and 5 did not display potent anti-inflammatory activities; however, compound 4 reduced IL-1ß production, and compound 5 diminished p65 translocation, with both exhibiting the capacity to inhibit TNF-α and IL-6 production. Collectively, the findings demonstrated that the P. excelsa extract was more efficacious than all tested compounds, while providing insights into the role of sulphation in the anti-inflammatory activity of naringenin derivatives.

Vasorelaxant Mechanism of Herbal Extracts from Mentha suaveolens, Conyza canadensis, Teucrium polium and Salvia verbenaca in the Aorta of Wistar Rats.

Mentha suaveolens (MS), Conyza canadensis (CC), Teucrium polium (TP) and Salvia verbenaca (SV) are used in Morocco to treat hypertension. Our aim was to characterize the composition and vasoreactivity of extracts of MS, CC, TP and SV. The chemical compositions of aqueous extracts of MS, SV and TP, and of a hydromethanolic extract of CC, were identified by HPLC-DAD. The vasoreactive effect was tested in rings of the thoracic aorta of female Wistar rats (8-14 weeks-old) pre-contracted with 10 µM noradrenaline, in the absence or presence of L-NAME 100 µM, indomethacin 10 µM or atropine 6 µM, to inhibit nitric oxide synthase, cyclooxygenase or muscarinic receptors, respectively. L-NAME and atropine decreased the vasorelaxant effect caused by low concentrations of MS. Atropine and indomethacin decreased the vasorelaxant effect of low concentrations of SV. High concentrations of MS or SV and the effect of SV and TP were not altered by any antagonist. The activation of muscarinic receptors and NO or the cyclooxygenase pathway underlie the vasorelaxant effect of MS and SV, respectively. Neither of those mechanisms underlines the vasorelaxant effect of CC and TP. These vasorelaxant effect might support the use of herbal teas from these plants as anti-hypertensives in folk medicine.

HPLC-DAD-ESI/MSn and UHPLC-ESI/QTOF/MSn characterization of polyphenols in the leaves of Neocarya macrophylla (Sabine) Prance ex F. White and cytotoxicity to gastric carcinoma cells.

Among several extracts from species from Guinea-Bissauan flora, the hydroethanol extract obtained from the leaves of gingerbread plum (Neocarya macrophylla (Sabine) Prance ex F. White.) revealed to be one of the most cytotoxic towards human gastric AGS carcinoma cells. Considering the increasing use of N. macrophylla in the food industry and the abundant biomass of agricultural wastes being generated, the identification of phenolic bioactives has been attained by HPLC-DAD-ESI/MSn and UHPLC-ESI/QTOF/MSn. Twenty-seven phenolic constituents were identified for the first time in the monotypic genus Neosartorya, 5-O-caffeoylquinic acid being detected as the major constituent (4.90 ± 0.20 mg g-1 dry extract). While 15 flavan-3-ols derivatives were determined, the extract is predominantly characterized by the occurrence of quercetin, kaempferol, apigenin and chrysoeriol glycosides. Typical apoptotic changes in gastric adenocarcinoma AGS cells upon exposure to N. macrophylla leaf extract were observed. The apoptotic cell death is mediated by the activation of the mitochondrial pathway, as loss of mitochondrial membrane potential was detected, as well as increased caspase-9 and -3 activities. The industrial relevance of this plant material, along with the data presented here on the potential anticancer effects of N. macrophylla and the efficient extraction of phenolic bioactives using water and ethanol (GRAS substance), calls for further research on the leaves as a potential functional food and/or ingredient.

Activation of caspase-3 in gastric adenocarcinoma AGS cells by Xylopia aethiopica (Dunal) A. Rich. fruit and characterization of its phenolic fingerprint by HPLC-DAD-ESI(Ion Trap)-MSn and UPLC-ESI-QTOF-MS2.

While the fruits of Xylopia aethiopica (Dunal) A. Rich. are important in African countries as a local trade product, their composition remains scarcely investigated. Phenolic fingerprint is herein delivered through HPLC-DAD-ESI(Ion Trap)-MSn and UPLC-ESI-QTOF-MS2 analysis, six cinnamoylquinic acid derivatives and twenty-four flavonoid glycosides being determined, chrysoeriol-7-O-glycosides being the main constituents. A cytotoxicity screening of twenty-eight hydroethanol extracts, obtained from a collection of Guinea-Bissauan plants, against A549 and AGS carcinoma cells, revealed the selective and potent effect towards AGS cells (IC50 = 151 × 10-3 g L-1), upon exposure to the extract from X. aethiopica fruits. Additional experiments demonstrated insignificant effect on LDH release at 151 × 10-3 g L-1, morphological analysis further suggesting induction of apoptosis. Pro-apoptotic effects were confirmed, as the extract enabled the activation of the effector caspase-3, broadening the knowledge on the anticancer mechanisms elicited by the fruits of X. aethiopica. Phenolic constituents might contribute to the cytotoxic effects, particularly via caspase-3 activation. Considering that X. aethiopica fruit is very often referred as an anticancer ingredient in Africa, but mainly the potent cytotoxicity herein recorded, our results call for additional research aiming to identify non-phenolic constituents contributing to the effects and also to further detail the anticancer mechanisms.

Cassia sieberiana DC. leaves modulate LPS-induced inflammatory response in THP-1 cells and inhibit eicosanoid-metabolizing enzymes.

ETHNOPHARMACOLOGICAL RELEVANCE: According to ethnobotanical surveys, Cassia sieberiana DC. (1825) is a particularly reputed species in African folk Medicine, namely due to the application of its leaves and roots for the treatment of diseases and symptomatology that appear to be related with an inflammatory background. In contrast with the roots of the plant, the leaves remain to be investigated, which prompted us to further detail mechanisms underlying their anti-inflammatory properties, by using in vitro models of disease. AIM OF THE STUDY: Considering its use in the amelioration and treatment of conditions that frequently underlie an inflammatory response, C. sieberiana leaves extract was prioritized amongst a collection of extracts obtained from plants collected in Guinea-Bissau. As such, this work aims to deliver experimental data on the anti-inflammatory properties of C. sieberiana leaf and to establish possible associations with its chemical composition, thus providing a rationale on its use in folk Medicine. MATERIALS AND METHODS: The chemical profile of an hydroethanol extract obtained from the leaves of the plant was established by HPLC-DAD-ESI/MSn in order to identify bioactives. The extract and its main compound were tested towards a series of inflammatory mediators, both in enzymatic and cell-based models. The capacity to interfere with the eicosanoid-metabolizing enzymes 5-lipoxygenase (5-LOX), cyclooxygenase-1 (COX-1) and -2 (COX-2) was evaluated in cell-free systems, while the effects in interleukin 6 (IL-6) and tumour necrosis factor-α (TNF-α) levels produced by THP-1 derived macrophages were assessed through ELISA. RESULTS: HPLC-DAD-ESI/MSn analysis of the extract elucidated a chemical profile qualitatively characterized by a series of anthraquinones, particularly rhein derivatives, and nine flavonols, most of which 3-O-glycosylated. Considering the concentrations of the identified compounds, quercetin was detached as the main component. Effects of the hydroethanol extract obtained from C. sieberiana leaves against key enzymes of the arachidonic acid cascade were recorded, namely a concentration-dependent inhibition against 5-LOX, at concentrations ranging from 16 to 250 µg mL-1 and a selective inhibitory action upon COX-2 (IC50 = 3.58 µg mL-1) in comparison with the isoform COX-1 (IC50 = 9.10 µg mL-1). Impact on inflammatory cytokines was also noted, C. sieberiana leaf extract significantly decreasing IL-6 levels in THP-1 derived macrophages at 250 and 500 µg mL-1. In contrast, TNF-α levels were found to be increased in the same model. Quercetin appears to partially account for the observed effects, namely due to the significant inhibitory effects on the activity of the arachidonic acid metabolizing enzymes COX-2 and 5-LOX. CONCLUSIONS: The anti-inflammatory effects herein reported provide a rationale for the use of C. sieberiana leaves in African folk practices, such as in the treatment of arthritis, rheumatism and body aches. Considering the occurrence of flavonoidic and anthraquinonic constituents, as well as the observed anti-inflammatory properties of quercetin, recorded effects must be related with the presence of several bioactives.

Inhibition of Proinflammatory Enzymes and Attenuation of IL-6 in LPS-Challenged RAW 264.7 Macrophages Substantiates the Ethnomedicinal Use of the Herbal Drug Homalium bhamoense Cubitt & W.W.Sm.

Commonly used to treat skin injuries in Asia, several Homalium spp. have been found to promote skin regeneration and wound healing. While ethnobotanical surveys report the use of H. bhamoense trunk bark as a wound salve, there are no studies covering bioactive properties. As impaired cutaneous healing is characterized by excessive inflammation, a series of inflammatory mediators involved in wound healing were targeted with a methanol extract obtained from H. bhamoense trunk bark. Results showed concentration-dependent inhibition of hyaluronidase and 5-lipoxygenase upon exposure to the extract, with IC50 values of 396.9 ± 25.7 and 29.0 ± 2.3 µg mL-1, respectively. H. bhamoense trunk bark extract also exerted anti-inflammatory activity by significantly suppressing the overproduction of interleukin 6 (IL-6) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages at concentrations ranging from 125 to 1000 µg mL-1, while leading to a biphasic effect on nitric oxide (NO) and tumor necrosis factor alpha (TNF-α) levels. The phenolic profile was elucidated by HPLC-DAD, being characterized by the occurrence of ellagic acid as the main constituent, in addition to a series of methylated derivatives, which might underlie the observed anti-inflammatory effects. Our findings provide in vitro data on anti-inflammatory ability of H. bhamoense trunk bark, disclosing also potential cutaneous toxicity as assessed in HaCaT keratinocytes.

Centaurium Erythraea Extracts Exert Vascular Effects through Endothelium- and Fibroblast-dependent Pathways.

Centaurium erythraea is a plant used in traditional medicine for several cardiovascular disorders, namely hypertension, but there is no scientific evidence able to provide a molecular basis for its claimed antihypertensive effects. After a preliminary screen of extracts obtained from sequential extraction of C. erythraea aerial parts, effects of the methanolic fraction (MFCE) on changes in perfusion pressure of isolated rat mesenteric vascular bed (MVB) and in rat cardiac fibroblasts proliferation were investigated, gathering information on the mechanisms involved in endothelium-dependent effects and their dependence on a pro-proliferative stimulus. The HPLC-DAD determination of the phenolics content of MFCE revealed the presence of 22 phenolic compounds. MFCE reduced (63.3 ± 3.9%; n = 4) perfusion pressure in MVB and almost completely abrogated the Ang II-induced increase in cardiac fibroblasts proliferation. Reduction of the perfusion pressure caused by MFCE was endothelium-dependent and occurred in parallel with an increase in NO release. These effects were inhibited by muscarinic receptor antagonists, by L-NAME (a NO synthase inhibitor), and by ODQ (a soluble guanylate cyclase inhibitor). Experiments revealed that effects required the involvement of K+ channels, being inhibited by tetraethylamonium (TEA; a Ca2+ activated K+ channels inhibitor) and by glibenclamide (an ATP-sensitive K+ channels inhibitor). In conclusion, extracts from C. erythraea, particularly the compounds present in the MFCE, induce endothelium-dependent vasodilation and prevent fibroblast proliferation induced by angiotensin II, which can account for the claimed antihypertensive effects of C. erythraea in traditional medicine.

Anti-inflammatory properties of Xylopia aethiopica leaves: Interference with pro-inflammatory cytokines in THP-1-derived macrophages and flavonoid profiling.

ETHNOPHARMACOLOGICAL RELEVANCE: Ethnopharmacological surveys on Guinea-Bissauan flora reveal that several species are used to treat or ameliorate the symptomatology of conditions with an inflammatory background. As such, extracts obtained from a series of plants recorded in those surveys were screened for their anti-inflammatory properties, a hydroethanolic extract obtained from the leaves of Xylopia aethiopica (Dunal) A. Rich, (Annonaceae), used on the treatment of headache, muscular pain and rheumatic pain, scoring positively and being further investigated. AIM OF THE STUDY: In order to identify species with anti-inflammatory properties, extracts were screened for their ability to interfere with LPS-induced TNF-α levels. Since significant effects were recorded upon treatment with the extract of the leaves obtained from X. aethiopica, further assays were conducted to elucidate additional mechanisms underlying its anti-inflammatory potential. Since little is known on the chemical composition of the plant, we also aimed to characterise its phenolic profile. MATERIALS AND METHODS: Interference with cytokines was evaluated by ELISA assay, through the quantification of TNF-α and IL-6 levels in the culture medium collected from LPS-activated THP-1-derived-macrophages. Inhibition of 5-lipoxygenase was assessed based on the oxidation of linoleic acid to 13-hydroperoxylinoleic acid. Characterization of the phenolic profile was attained by HPLC-DAD. RESULTS: Evaluation of TNF-α levels in LPS-challenged THP-1 macrophages evidenced a significant inhibition (>90%) upon treatment with the hydroethanolic extract obtained from X. aethiopica leaves at a concentration of 500 µg/mL. Additional anti-inflammatory effects were recorded, including a significant decrease on IL-6 levels at 250 and 500 µg/mL. The extract proved to be active towards 5-LOX, leading to significant inhibition at concentrations ranging from 16 to 250 µg/mL (IC50 = 85 µg/mL). Phenolic profiling allowed the identification and quantitation of eight constituents, including caffeoylquinic acids (1-3), mono-O-glycosylated flavonols (5-8), and the mono-O-glycosyl flavone luteolin-7-O-glucoside (4). The main phenolic constituent, kaempferol-3-O-rutinoside (8), was found to significantly contribute to the anti-inflammatory effects, namely through the inhibition of 5-LOX. However, no effects on the decrease of TNF-α and IL-6 levels caused by this phenolic compound were found. CONCLUSION: The anti-inflammatory effects of X. aethiopica leaves are demonstrated experimentally, thus substantiating its use in folk Medicine. Relevantly, the observed anti-inflammatory properties can stimulate further studies in order to fully unveil the therapeutic potential of the plant, namely as a source of phenolic compounds with a significant ability to interfere with conventional inflammatory targets.

Flavonoid Composition of Salacia senegalensis (Lam.) DC. Leaves, Evaluation of Antidermatophytic Effects, and Potential Amelioration of the Associated Inflammatory Response.

Predominantly spread in West Tropical Africa, the shrub Salacia senegalensis (Lam.) DC. is known because of its medicinal properties, the leaves being used in the treatment of skin diseases. Prompted by the ethnomedicinal use, a hydroethanolic extract obtained from the leaves of the plant was screened against a panel of microbial strains, the majority of which involved in superficial infections. The extract was found to be active against the dermatophytes Trichophyton rubrum and Epidermophyton floccosum. Notable results were also recorded regarding the attenuation of the inflammatory response, namely the inhibitory effects observed against soybean 5-lipoxygenase (IC50 = 71.14 µg mL-1), no interference being recorded in the cellular viability of RAW 264.7 macrophages and NO levels. Relevantly, the extract did not lead to detrimental effects against the keratinocyte cell line HaCaT, at concentrations displaying antidermatophytic and anti-inflammatory effects. Flavonoid profiling of S. senegalensis leaves was achieved for the first time, allowing the identification and quantitation of myricitrin, three 3-O-substituted quercetin derivatives, and three other flavonoid derivatives, which may contribute, at least partially, to the observed antidermatophytic and anti-inflammatory effects. In the current study, the plant S. senegalensis is assessed concerning its antidermatophytic and anti-inflammatory properties.

HPLC-DAD-ESI/MSn phenolic profile and in vitro biological potential of Centaurium erythraea Rafn aqueous extract.

Centaurium erythraea Rafn is a food flavouring used in both food and beverage industries. Despite the existence of some works on this species, only few focus their attention on its common form of consumption (infusion). Thus, we intended to explore the chemical composition and the biological properties of infusions from C. erythraea aerial parts. Phenolic compounds were identified by HPLC-DAD-ESI/MSn, twenty-two flavonoid derivatives being reported for the first time. Concerning to the biological potential, the best scavenging activity was observed for the superoxide anion radical. Moreover, this extract revealed to have some effect on the inhibition of 5-lipoxygenase, no cytotoxicity against RAW 264.7 macrophage cells line, and a weak potential to decrease the nitric oxide levels in this cell system. The results suggest that C. erythraea aerial parts could be valuable sources of health benefits compounds, contributing to its valorisation and its further application in functional foods.

Chemical findings and in vitro biological studies to uphold the use of Ficus exasperata Vahl leaf and stem bark.

Ficus exasperata Vahl, commonly known as sandpaper, is a terrestrial Afro-tropical tree used in popular medicine. Despite the existence of some works on the biological activities of this species, its chemical composition is still poorly known. The aim of this study was to extend the knowledge on the phytochemistry and biological properties of this species. Aqueous extracts from F. exasperata leaves and stem bark were analysed. Thirty-one phenolic compounds, comprising cinnamoyl derivatives, flavonoid-O-glycosides, flavonoid-mono-C-glycosides, flavonoid-di-C-glycosides and one furanocoumarin, were determined by HPLC-DAD-ESI/MSn and UPLC-ESI-QTOF-MS, 26 of them being reported for the first time in this species. The profile of organic acids, characterized by HPLC-UV, was also reported for the first time. The best radical scavenging activity was observed for the aqueous extract from leaves (IC50 values of 222.5, 510.0 and 50.0 µg/mL against DPPH•, •NO and O2•-, respectively). In addition, both aqueous extracts of the leaves and stem bark displayed a weak effect on α-amylase, and no cytotoxicity against gastric adenocarcinoma cell line, AGS. This study contributes to the valorisation of these vegetal materials, which may have application in functional foods and/or nutraceuticals.

Accumulation of primary and secondary metabolites in edible jackfruit seed tissues and scavenging of reactive nitrogen species.

Studies involving jackfruit tree (Artocarpus heterophyllus Lam.) focus on its fruit. Nevertheless a considerable part of jackfruit weight is represented by its seeds. Despite being consumed in several countries, knowledge about the chemical composition of these seeds is scarce. In this work, the accumulation of primary and secondary metabolites in jackfruit seed kernel and seed coating membrane was studied. Sixty-seven compounds were identified, sixty of them being reported for the first time in jackfruit seed. Both tissues had a similar qualitative profile, but significant quantitative differences were found. The capacity of aqueous extracts from jackfruit seed kernel and seed coating membranes to scavenge nitric oxide radical was also evaluated for the first time, the extract prepared from the seed coating membrane being the most potent. This work increases the potential revenue from a food that is still largely wasted.

Exploratory Studies on the in Vitro Anti-inflammatory Potential of Two Herbal Teas (Annona muricata L. and Jasminum grandiflorum L.), and Relation with Their Phenolic Composition.

The need of new anti-inflammatory drugs has led to the search for safer and more potent molecules in distinct sources, such as natural products. This work aimed to explore the anti-inflammatory potential of aqueous extracts from two herbal teas (Annona muricata L. and Jasminum grandiflorum L.) in RAW 264.7 macrophages cells and in cell-free assays. Furthermore, the phenolic composition of both extracts and of their hydrolysates was characterized by HPLC-DAD, in order to establish possible relationships with the biological activity. In a general way, A. muricata displayed a stronger capacity to inhibit nitric oxide (NO) production and the activity of phospholipase A2 (PLA2 ), displaying an IC50 value of 142 µg/ml against this enzyme. A deeper look at phenolic compounds revealed that aglycones had more capacity to inhibit NO and PLA2 than their corresponding glycosides, quercetin being clearly the most potent one (IC50  = 7.47 and 1.36 µm, respectively). In addition, 5-O-caffeoylquinic acid, at 1.56 µm, could also inhibit PLA2 (ca. 35%). Our findings suggest that the consumption of both herbal teas may be a preventive approach to inflammatory disorders.

Digestive Gland from Aplysia depilans Gmelin: Leads for Inflammation Treatment.

The exploitation of marine organisms for human nutritional and pharmaceutical purposes has revealed important chemical prototypes for the discovery of new drugs, stimulating compounds isolation and syntheses of new related compounds with biomedical application. Nowadays, it is well known that inflammatory processes are involved in many diseases and the interest in the search for marine natural products with anti-inflammatory potential has been increasing. The genus Aplysia belongs to the class Gastropoda, having a wide geographical distribution and including several species, commonly known as sea hares. Aplysia depilans Gmelin is usually found in the Mediterranean Sea and in the Atlantic Ocean, from West Africa to the French coast. In these marine organisms, most of the digestion and nutrient absorption occurs in the digestive gland. This work aimed to explore the chemical composition and bioactivity of the methanol extract from A. depilans digestive gland. Therefore, fatty acids and carotenoids were determined by GC-MS and HPLC-DAD, respectively. Twenty-two fatty acids and eight carotenoids were identified for the first time in this species. The A. depilans digestive gland revealed to be essentially composed by polyunsaturated fatty acids (PUFA) and xanthophylls. Regarding the anti-inflammatory potential in RAW 264.7 cells stimulated with lipopolysaccharide, it was observed that this matrix has capacity to reduce nitric oxide (NO) and L-citrulline levels, which suggests that its compounds may act by interference with inducible nitric oxide synthase. Taking into account the results obtained, A. depilans digestive gland may be a good source of nutraceuticals, due to their richness in health beneficial nutrients, such as carotenoids and long-chain PUFA.

Piper betle leaves: profiling phenolic compounds by HPLC/DAD-ESI/MS(n) and anti-cholinesterase activity.

INTRODUCTION: Piper betle L. is a widely distributed plant in the tropical and subtropical regions, its leaves being largely consumed as a masticator and mouth freshener. OBJECTIVE: The purposes of this work were to characterise the phenolic profile of this species and to improve knowledge of its anti-cholinesterase properties. METHODS: The phenolic composition of P. betle leaf aqueous and ethanol extracts was characterised by HPLC coupled with a diode-array detector and combined with electrospray ionisation tandem MS, and in vitro cholinesterase inhibitory capacity of both extracts was assessed by spectrophotometric microassays. The effect on neuronal cells (SH-SY5Y) viability was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction and lactate dehydrogenase leakage. RESULTS: Twelve phenolic compounds, comprising a phenylpropanoid, five cinnamoyl and six flavonoids derivatives were identified in P. betle leaves. Hydroxychavicol was the major compound in both extracts; however, the aqueous extract presented a greater diversity of compounds. Both extracts showed strong activity against both acetyl- and butyrylcholinesterase, which can be due, at least partially, to the phenolic composition. Furthermore, the aqueous extract proved to be cytotoxic to human neuroblastoma cells at concentrations higher than 500 µg/mL. CONCLUSION: The results suggest that the consumption of P. betle leaves as an infusion can have a positive impact in the prevention and treatment of neurodegenerative diseases. Apigenin and luteolin derivatives are reported for the first time in this species.

A new iced tea base herbal beverage with Spergularia rubra extract: metabolic profile stability and in vitro enzyme inhibition.

Beverages are an ideal format to offer nutrients, specific health-promoting functionality, and desirable sensory attributes to consumers. Taking into account previous research on Spergularia rubra (L.) J. Presl & C. Presl, the aim of this work was to describe the chemistry and biochemistry associated with the production of a new iced tea base herbal beverage containing a hydroethanolic extract of this species, including both naturally occurring and added components. Phenolic compounds of S. rubra hydroethanolic extract and of the iced tea base herbal beverage were determined by HPLC-DAD. Thirty compounds, comprising nonacylated C-glycosyl flavones, C-glycosyl flavones acylated with aromatic acids, and C-glycosyl flavones acylated with aliphatic acids, were identified, being essentially represented by apigenin derivatives. Organic acids of both samples were determined by HPLC-UV, malic acid being the major one. A strong inhibition of α-glucosidase, acetylcholinesterase, and butyrylcholinesterase was observed. Furthermore, the influence of the pH of the digestive tube on the chemical composition of both extract and iced tea base herbal beverage and, consequently, on their biological activity, was assessed. In a general way, pH variation significantly decreased (p < 0.05) the metabolites content and enzymes inhibitory capacity. Nevertheless, the beverage enriched with S. rubra extract represents a valuable addition to consumer's health and nutrition, once the loss of activity is lower than the one verified for the base iced tea. Thus, the results suggest that the ingestion of this beverage could be of potential interest for several chronic disorders, particularly Alzheimer's disease.

Influence of Tunisian Ficus carica fruit variability in phenolic profiles and in vitro radical scavenging potential

Ficus carica L., Moraceae, is one of the first plants that were cultivated by humans, being the fruit an important crop worldwide for dry and fresh consumption. In this work, phenolics and antioxidant potential of dried fruits of seventeen Tunisian F. carica varieties, from green, red and black phenotypes, were assessed for the first time. HPLC-DAD analysis was performed. All samples presented a similar qualitative profile. The phenolics content ranged between 29.18 and 55.56 mg/kg (in black and red phenotypes, respectively) and quercetin-3-O-rutinoside was always the major compound. The antioxidant potential against DPPH•, superoxide and nitric oxide radicals of three varieties representing each phenotype was checked. All samples exhibited activity against the first two radicals in a concentration-dependent way, "Bayoudi" variety being the most effective one (IC25 values of 10.32 and 2.89 µg/ mL, respectively). Nevertheless, only "Hammouri" variety presented some capacity to scavenge nitric oxide radical. Our results reveal nice perspectives for these typical fruits, as they present an interesting phenolic composition and good antiradical activity and may encourage their consumption for health protection.

Metabolic and biological prospecting of Coreopsis tinctoria

Coreopsis tinctoria Nutt., Asteraceae, flowering tops infusion has been traditionally used in many countries to control hyperglycaemia. In this work we report for the first time fatty acids and volatile compounds in this species. Fifteen fatty acids and sixteen volatile compounds were determined by GC-ITMS, being saturated fatty acids and monoterpenes the main compounds. The antioxidant and antibacterial potential of this matrix was checked for the first time by several in vitro assays. A concentration-dependent activity was noticed against DPPH, nitric oxide and superoxide radicals. Antibacterial capacity was assessed against Gram-positive and Gram-negative bacteria, being more effective against the first. Additionally, acetylcholinesterase and butyrylcholinesterase inhibitory activity was also evaluated, but no effect was found. Our results provide evidence of a wide diversity of compounds with several biological properties, improving the knowledge on this poorly studied matrix, which can lead to an increment of the use of C. tinctoria flowering tops, namely in food and pharmaceutical applications.

Further insight into the latex metabolite profile of Ficus carica.

Latex is a sticky emulsion that exudes upon damage from specialized canals from several plants. It contains several biologically active compounds, such as phytosterols, fatty acids, and amino acids. In plants, these compounds are involved in the interaction between plants, insects, and the environment. Despite its chemical, biological, and ecological importance, Ficus carica latex is still poorly studied. To improve the knowledge on the metabolite profile of this matrix, a targeted metabolite analysis was performed in a representative sample from F. carica latex. Seven phytosterols were determined by gas chromatography-ion trap mass spectrometry (GC-ITMS) and high-performance liquid chromatography coupled to diode array detection (HPLC-DAD), with ß-sitosterol and lupeol being the compounds present in higher concentrations (ca. 54 and 14%, respectively). A total of 18 fatty acids were characterized by GC-ITMS, being essentially represented by saturated fatty acids (ca. 86.4% of total fatty acids). A total of 13 free amino acids were also identified by high-performance liquid chromatography coupled to ultraviolet-visible spectroscopy (HPLC/UV-vis), and cysteine and tyrosine were the major ones (ca. 38.7 and 31.4%, respectively). In humans, phytosterols and some polyunsaturated fatty acids, such as linoleic acid, are known for their anticarcinogenic properties. With regard to amino acids, some of them, such as glycine, are neurotransmitters. Our results reveal the presence of a wide diversity of compounds, from distinct classes, in F. carica latex, possessing various potential pharmacological activities; thus, its biological potential appears to be worth further exploring.