Anthraquinone profile, antioxidant and enzyme inhibitory effect of root extracts of eight Asphodeline taxa from Turkey: can Asphodeline roots be considered as a new source of natural compounds?

Phenolic enriched fraction of Clerodendrum glandulosum Lindl. leaf extract ameliorates hyperglycemia and oxidative stress in streptozotocin-nicotinamide induced diabetic rats

BACKGROUND

Clerodendrum glandulosum Lindl. is an important ethnomedicinal shrub of Northeast India, used by traditional healers to control various ailments like diabetes, hypertension, arthritis, etc. OBJECTIVES: The present study was conducted to explore the anti-hyperglycemic and antioxidative effects of the polyphenol-rich fraction (PRF) of C. glandulosum leaf extract and identification of its major bioactive compounds. Further, an in-silico molecular docking study was also performed to understand the molecular interactions of the identified major compounds with some target proteins associated with diabetic complications.

MATERIALS AND METHODS

PRF was purified from the hydromethanolic (80% MeOH) extract of leaves and subjected to assessment of in-vitro antioxidant and anti-diabetic properties. It was also subjected to evaluate the ameliorative effect during streptozotocin-nicotinamide-induced hyperglycemia in Wistar albino rats. An in-silico molecular docking study was also performed to complement the in-vitro/in-vivo studies.

RESULTS

Chemical analysis of PRF showed the presence of phenolics like caffeic acid, verbascoside, isoverbascoside, and apigenin, of which verbascoside (598.14 ± 1.24 mg/g) was found to be the principal compound. In-vitro studies showed potent antioxidant (IC50 of DPPH:32.45 ± 2.16 μg/mL; ABTS:39.08 ± 0.53 μg/mL) properties and excellent aldose reductase inhibition potential (IC50 2.18 ± 0.10 μg/mL). Treatment with PRF showed reduced blood glucose levels and increased plasma insulin levels. The results also indicate an improvement of endogenous antioxidants and suppression of inflammatory cytokines (IL-6 and TNF-α) comparable to the standard. Molecular docking studies predicted promising interactions between the identified molecules and the crucial amino acid residues of the enzymes involved in the development of hyperglycemia.

CONCLUSION

This study revealed the antihyperglycemic and antioxidant potential of partially purified fraction PRF of C. glandulosum leaves.

Antimicrobial and Cytotoxic Potential of Helminthosporin from Rumex abyssiniscus Jacq. Discovered as a Novel Source of Syringic Acid and Bis(2-ethyloctyl) Phthalate

Rumex abyssinicus Jacq. is a perennial medicinal herb widely used in traditional medicine to treat many diseases. Phytochemicals of the plant were isolated using column chromatography and thin layer chromatography techniques. Extract, fractions and pure compounds were screened for antimicrobial activity against sensitive and multi-drug resistant microbes and their cytotoxicity was performed on different cancer cell lines. The mechanism of action of purified helminthosporin as well as the potent fraction containing a mixture of two compounds was assessed. Fraction R7C3 was the most potent antibacterial with the lowest MIC value of 0.12 µg/mL. Helminthosporin was the most potent compound with the lowest MIC value of 1.95 µg/mL. The compound was more potent than the antibiotic chloramphenicol against multi-drug resistant (MDR) bacteria with MIC equal to 16 µg/mL. The fraction and helminthosporin were shown to destroy the cell wall of the yeast and bacteria, and DNA fragmentation effect on the genome of Candida albicans and Bacillus cereus. Helminthosporin was the most cytotoxic compound with IC₅₀ ˂ 10 µM. Fraction R7C3 showed the most potent cytotoxic effects on all cancer cell lines, with IC₅₀ ranging from ˂1 to 4.35 ng/mL. Our study is the first report on the mechanism of action of helminthosporin, a potent candidate in the development of new drugs against multi-resistant bacteria and cancer cells. In addition, this study uncovered Rumex abyssinicus as a new source of syringic acid and bis(2-ethyloctyl) phthalate.

Chemodiversity, Biological Activities and Molecular Docking Studies of Leptadenia pyrotechnica (Forssk.) Decne: A Comprehensive Approach to Validate Its Medicinal Use

Leptadenia pyrotechnica (Forssk.) Decne is growing in Cholistan desert, and is known for its laxative, analgesic, anabolic and astringent, antioxidant, anti-inflammatory, antibacterial, antitumor, hypolipidemic and antiatherosclerotic properties. The present study disclosed the metabolic picture of L. pyrotechnica and validates its folk uses. LP-H fraction constitute 25.79±0.11 mgGAE/g extract and 20.64±0.33 mgRE/g extract of phenolic and flavonoid content, respectively, followed by LP-E (23.15±0.33 mgGAE/g extract and 19.40±0.13 mgRE/g extract), however, LP-E exhibited the highest free radical scavenging (DPPH: 21.05±0.45mgTE/g and ABTS: 68.12±0.53 mgTE/g) and metal reducing (FRAP: 44.93±1.66, CUPRAC: 117.42±1.28 mgTE/g, respectively) activities. The total antioxidant capacity in Phosphomolybdenum assay (1.52±0.14 mmolTE/g) and ferrous ion chelating (11.57±0.29 mgEDTAE/g) activities were observed highest for LP-H extract. In cholinesterase's inhibitory assays, the LP-E and LP-W extracts exhibited inhibitory values as 2.43 and 2.40±0.07 mgGALAE/g extract, respectively against AChE, while against BChE the LP-H displayed the highest value as 5.98±0.44 mgGALAE/g extract. The LP-H fraction also showed the highest inhibition potential (7.72±0.14 mmol ACAE/g and 0.55±0.01 mmol ACAE/g, respectively) against α-glucosidase and α-amylase enzymes, while, in tyrosinase inhibitory assay, all the fractions exhibited significant activities in the range of 59.35±0.29 to 55.18±0.49 mgKAE/g extract. RP-UHPLC/MS analysis of LP-M disclosed the presence of 57 metabolites of various classes. A multivariate analysis and molecular docking study was also carried out to establish relationships between the metabolites and the biological activities, which finally validate the use of L. pyrotechnica as herbal medicine or component nutraceutical, food and cosmetic industry.

Radical Scavenging Activity of Natural Anthraquinones: a Theoretical Insight

Anthraquinones (ANQs) isolated from Paederia plants are known to have antidiarrheal, antitussive, anthelmintic, analgesic, anti-inflammatory, antihyperlipidemic, antihyperglycaemic, and antimicrobial activities. The antioxidant properties were also noted but not confirmed thus far. In this study, the superoxide and hydroperoxide radical scavenging activities of six ANQs were evaluated using a computational approach. The results suggest that the ANQs exhibit low HOO• antiradical activity in all environments, including the gas phase (k < 102 M-1 s-1). In contrast, the ANQs might exert excellent O2 •- radical scavenging activity, particularly in aqueous solution. The rate constants of the superoxide anion scavenging in water (at pH = 7.4) range from 3.42 × 106 to 3.70 × 108 M-1 s-1. Compared with typical antioxidants such as ascorbic acid and quercetin, the superoxide anion scavenging activity of ANQs is significantly higher. Thus, the ANQs are promising O2 •- radical scavengers in polar media.

Modulation of CYP3A4 and CYP2C9 activity by Bulbine natalensis and its constituents: An assessment of HDI risk of B. natalensis containing supplements

BACKGROUND

Bulbine natalensis is an African-folk medicinal plant used as a dietary supplement for enhancing sexual function and muscle strength in males by presumably boosting testosterone levels, but no scientific information is available about the possible herb-drug interaction (HDI) risk when bulbine-containing supplements are concomitantly taken with prescription drugs.

PURPOSE

This study was aimed to investigate the HDI potential of B. natalensis in terms of the pregnane X receptor (PXR)-mediated induction of major drug-metabolizing cytochrome P450 enzyme isoforms (i.e., CYP3A4 and CYP2C9) as well as inhibition of their catalytic activity.

RESULTS

We found that a methanolic extract of B. natalensis activated PXR (EC₅₀ 6.2 ± 0.6 µg/ml) in HepG2 cells resulting in increased mRNA expression of CYP3A4 (2.40 ± 0.01 fold) and CYP2C9 (3.37 ± 0.3 fold) at 30 µg/ml which was reflected in increased activites of the two enzymes. Among the constituents of B. natalensis, knipholone was the most potent PXR activator (EC₅₀ 0.3 ± 0.1 µM) followed by bulbine-knipholone (EC₅₀ 2.0 ± 0.5 µM), and 6'-methylknipholone (EC₅₀ 4.0 ± 0.5 µM). Knipholone was also the most effective in increasing the expression of CYP3A4 (8.47 ± 2.5 fold) and CYP2C9 (2.64 ± 0.3 fold) at 10 µM. Docking studies further confirmed the unique structural features associated with knipholones for their superior inductive potentials in the activation of PXR compared to other anthraquinones. In a CYP inhibition assay, the methanolic extract as well as the anthraquinones strongly inhibited the catalytic activity of CYP2C9 while, inhibition of CYP3A4 was weak.

CONCLUSIONS

These results suggest that consumption of B. natalensis may pose a potential risk for HDI if taken with conventional medications that are substrates of CYP3A4 and CYP2C9 and may contribute to unanticipated adverse reactions or therapeutic failures. Further studies are warranted to validate these findings and establish their clinical relevancy.

In vitro targeted screening and molecular docking of stilbene, quinones, and flavonoid on 3T3-L1 pre-adipocytes for anti-adipogenic actions

In metabolic disorders like obesity, NAFLD and T2DM, adipocytes are dysfunctional. Hence, pharmacological interventions have importance in preventing differentiation of adipocytes and stimulating lipid uptake. We, therefore, investigated the effects of arbutin (ARB), purpurin (PUR), quercetin (QR), and pterostilbene (PTS) on adipocyte differentiation and lipid uptake using 3T3-L1 adipocytes. Further, in silico docking studies were achieved to investigate interactions of ARB, PUR, QR, and PTS with beta-ketoacyl reductase (KR) and thioesterase (TE) domains of fatty acid synthase (FAS) enzyme. Mature 3T3-L1 adipocytes were used to investigate the anti-adipogenic effect of selected pharmacological agents by Oil Red O staining and in vitro fatty acid uptake analysis. Molecular docking studies were performed to predict the binding interactions of selected compounds with KR and TE domains of FAS enzyme. All these agents significantly decrease the adipocyte differentiation and showed the stimulatory effect on fatty acid uptake in 3T3-L1 adipocytes. However, PTS and PUR proved to be anti-adipogenic, whereas ARB and QR showed significant effect on fatty acid uptake, compared to others. Similarly, all the compounds displayed significant binding interactions with KR and TE domains of FAS enzyme, supporting the results of in vitro studies. Graphical abstract.

Investigations on acute oral toxicity studies of purpurin by application of OECD guideline 423 in rodents

The anticancer, anti-inflammatory and antioxidant properties of Purpurin were generated from in vitro studies, and no scientific reports were found on its safety and efficacy, related to their in vivo studies; thus, the present study was focused on acute oral toxicity of purpurin in female Wistar rats as per the OECD 423 guidelines. In this study, purpurin was administered at starting dosage of 300 mg/kg followed by 2000 mg/kg, p.o, and animals were observed for toxic signs at 24 h and for the next 14 days to different animal groups. Animals were observed for mortality, behavioral changes, biochemistry, hematological parameters, and histopathological examination after a follow up on the 14th day. The oral lethal dose for mice was greater than 2000 mg/kg, b.wt. in female rats and classified under category 5 as per the acute oral toxicity study. It was found that there were no significant differences in body weight changes, food/water intake, hematology, and clinical biochemistry. The histopathological study directly depicted that there were no pathological changes observed in the vital organs of rats treated with the different dose of Purpurin. The present work advocates that an acute oral administration of Purpurin was found to be a non-toxic and safe drug in the tested experimental conditions.

Investigation of α-Glucosidase Inhibitory Metabolites from Tetracera scandens Leaves by GC-MS Metabolite Profiling and Docking Studies

Stone leaf (Tetracera scandens) is a Southeast Asian medicinal plant that has been traditionally used for the management of diabetes mellitus. The underlying mechanisms of the antidiabetic activity have not been fully explored yet. Hence, this study aimed to evaluate the α-glucosidase inhibitory potential of the hydromethanolic extracts of T. scandens leaves and to characterize the metabolites responsible for such activity through gas chromatography-mass spectrometry (GC-MS) metabolomics. Crude hydromethanolic extracts of different strengths were prepared and in vitro assayed for α-glucosidase inhibition. GC-MS analysis was further carried out and the mass spectral data were correlated to the corresponding α-glucosidase inhibitory IC₅₀ values via an orthogonal partial least squares (OPLS) model. The 100%, 80%, 60% and 40% methanol extracts displayed potent α-glucosidase inhibitory potentials. Moreover, the established model identified 16 metabolites to be responsible for the α-glucosidase inhibitory activity of T. scandens. The putative α-glucosidase inhibitory metabolites showed moderate to high affinities (binding energies of -5.9 to -9.8 kcal/mol) upon docking into the active site of Saccharomyces cerevisiae isomaltase. To sum up, an OPLS model was developed as a rapid method to characterize the α-glucosidase inhibitory metabolites existing in the hydromethanolic extracts of T. scandens leaves based on GC-MS metabolite profiling.

New pharmacological targets of three Asphodeline species using in vitro and ex vivo models of inflammation and oxidative stress

This study explored the efficacy of the methanolic extract of three Asphodeline species (A. damascena subsp. rugosa, A. tenuior subsp. tenuiflora var. tenuiflora, and A. cilicica) to protect against hydrogen peroxide (H₂O₂)-induced lactate dehydrogenase (LDH) activity in HCT116 cells, and also any protective effects against lipopolysaccharides (LPS)-induced nitrite levels, prostaglandin E2 (PGE2) and 8-iso-prostaglandin F2α (8-iso-PGF2α) levels, 5HIAA/5-HT ratio, tumor necrosis factor (TNF)-α and interleukin (IL)-6 gene expression in rat colon specimens. Interestingly, A. tenuior extract was most effective in improving the tested biomarkers, by reducing LDH activity and nitrite level. On the other hand, A. damascena was the only species able to blunt LPS-induced TNF-α gene expression in rat colon specimens. The present findings highlighted the protective effects of Asphodeline extracts via in vitro and ex vivo models of inflammation and oxidative stress, adding new insights to the pharmacological actions of these medicinal plant species. Abbreviations: IBD: inflammatory bowel disease; LPS: lipopolysaccharide; LDH: lactate dehydrogenase; 5HIAA: 5-hydroxyindoleacetic acid; 5-HT: 5-hydroxytryptamine.

Protective effects induced by alcoholic Phlomis fruticosa and Phlomis herba-venti extracts in isolated rat colon: Focus on antioxidant, anti-inflammatory, and antimicrobial activities in vitro

Phlomis fruticosa L. and P. herba-venti are species belonging to the Lamiaceae family, which have been traditionally used to prepare tonic and digestive drinks. Multiple studies also demonstrated the inhibitory effects of P. fruticosa extracts and essential oil against oxidative/proinflammatory pathways and bacterial strains deeply involved in ulcerative colitis. Considering these findings, the present study evaluated the effects of alcoholic P. fruticosa and P. herba-venti leaf extracts in isolated rat colon challenged with Escherichia coli lipopolysaccharide (LPS), an ex vivo experimental paradigm of ulcerative colitis. In this context, we assayed colon levels of pro-oxidant and proinflammatory biomarkers, including nitrites, malondialdehyde (MDA), lactate dehydrogenase (LDH), and serotonin (5-HT). Additionally, the extracts have been tested in order to evaluate possible inhibitory effects on specific bacterial and fungal strains involved in ulcerative colitis. Alcoholic P. fruticosa and P. herba-venti extracts were able to blunt LPS-induced nitrite, MDA, 5-HT, and LDH levels in isolated rat colon. The same extracts also inhibited the growth of Pseudomonas aeruginosa, E. coli, Staphylococcus aureus, Candida albicans and Candida tropicalis. In conclusion, our findings show a potential role exerted by alcoholic P. fruticosa and P. herba-venti in managing the clinical symptoms related to ulcerative colitis.

In vitro antioxidant and enzyme inhibitory properties of Rubus caesius L

The genus Rubus (Rosaceae) has great potential for and a history of use as natural agents in several traditional folk remedies. Based on this concept, this study focused on the antioxidant activities and enzyme inhibitory effects of extracts and fractions from Rubus caesius. Different chemical assays were performed to detect antioxidant capacity, namely, free radical scavenging (ABTS and DPPH assays), reducing power (CUPRAC and FRAP), phosphomolybdenum and metal chelating. Enzyme inhibitory effects were tested towards cholinesterases (AChE and BChE), tyrosinase, α-amylase and α-glucosidase. In addition, total amounts of phenolics and flavonoids were detected by colorimetric assays. Among the samples, the ethyl acetate fraction exhibited the strongest antioxidant potential with its higher concentration of total phenolics. The highest AChE and α-amylase inhibitory activities were observed in the diethyl ether fraction, while the n-butanol fraction had the strongest anti-tyrosinase inhibitor ability. The present study demonstrated that R. caesius may be considered a source of biologically active compounds to develop novel functional products or drugs in the pharmaceutical field.

A comparative study of UHPLC/Orbitrap MS metabolomics profiles and biological properties of Asphodeline taurica from Bulgaria and Turkey

The present investigation attempts to compare the pharmacological properties and phytochemical profile of four extracts (ethyl acetate, dichloromethane, methanol, and water) of Asphodeline taurica (Pall.) Endl. roots from Bulgaria and Turkey. The Bulgarian ethyl acetate extract displayed the highest antioxidant activity in the DPPH, CUPRAC, and phosphomolybdenum assay, and strongest inhibition against α-amylase and α-glucosidase. The Turkish aqueous extract exhibited the strongest ABTS scavenging and ferric reducing power while its methanol extract was the most effective acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitor. On the other hand, the Turkish dichloromethane extract showed the highest lipase inhibition. UHPLC/Orbitrap MS analysis showed a wide array of individual phenolics; six free anthraquinones, two bianthraquinones, three bianthracenes, three anthraquinone glycosides and one bianthracen glycoside were identified. The present data suggest that A. taurica roots can be considered as a valuable source of biologically active phytocompounds with functional properties for the cosmetic and pharmaceutical industries.

Determination of antioxidant capacity of thiol-containing compounds by electron spin resonance spectroscopy based on Cu2+ ion reduction

Electron spin resonance spectroscopy was applied to determining the antioxidant capacity of eight thiol-containing compounds, including reduced glutathione, N-acetyl-L-cycsteine, methimazole, captopril, and tiopronin with one thiol group, 1,4-dithioerythritol and 2,3-dimercapto-1-propanol with two thiol groups, as well as L-cystine with no free thiol group. Cu²⁺ ion gives an electron spin resonance signal and is reduced to Cu⁺ ion with no electron spin resonance signal by the free thiol group in the compounds. Trolox equivalent antioxidant capacity (TEAC) was used to evaluate the reducing ability of the thiol-containing compounds and the TEAC values were found to be relevant to the number of thiol groups contained in the compounds. For the purpose of comparison, the UV-vis spectrophotometry, cupric reducing antioxidant capacity (CUPRAC) method, and Ellman assay were applied to the determination of the antioxidant capacity of the thiol-containing compounds. The TEAC values obtained by the present method were very close to those obtained by UV-vis method. However, compared with CUPRAC method, for methimazole the present method gave a more reasonable TEAC value. The present method was also applied to the quantification of N-acetyl-L-cycsteine, methimazole, captopril, and tiopronin in their pharmaceutical formulations.

A Comparative Assessment of Biological Effects and Chemical Profile of Italian Asphodeline lutea Extracts

The present study aims to highlight the therapeutic potential of Asphodeline lutea (AL), a wild edible plant of the Mediterranean diet. Roots, aerial parts, and flowers of AL at two different phenological stages were collected from three locations in Italy. The inhibitory activities of extracts on strategic enzymes linked to human diseases were assessed. The antioxidant properties were evaluated in vitro, using six standard bioassays. The phenolic and anthraquinone profiles were also established using HPLC-PDA. Zinc, cadmium, lead, and copper contents were also determined. All the samples inhibited acetylcholinesterase (from 1.51 to 2.20 mg GALAEs/g extract), tyrosinase (from 7.50 to 25.3 mg KAEs/g extract), and α-amylase (from 0.37 to 0.51 mmol ACAEs/g extract). Aloe-emodin and physcion were present in all parts, while rhein was not detected. The phenolic profile and the heavy metals composition of specimens gathered from three different regions of Italy were different. It can be argued that samples collected near the street can contain higher concentrations of heavy metals. The experimental data confirm that the A. lutea species could be considered as a potential source of bioactive metabolites, and its consumption could play a positive and safe role in human health maintenance.

Synthesis of α-glycosidase hybrid nano-flowers and their application for enriching and screening α-glycosidase inhibitors

To rapidly and accurately screen compounds present in traditional Chinese herbal medicines for α-glycosidase inhibitors, we synthesized a novel nano-affinity material to enable the targeted screening of α-glycosidase inhibitors.

Chemical Composition of Essential Oil, Antioxidant, Antidiabetic, Anti-obesity, and Neuroprotective Properties of Prangos gaubae

Chemical composition of essential oil and the potential of Prangos gaubae for the management of public health problems such as Alzheimer's disease, obesity, Diabetes mellitus, and skin diseases were evaluated for the first time. In this direction, enzyme inhibitory effects, antioxidant activity, and total bioactive contents of the plant were determined. EO showed high acetylcholinesterase (2.97 mg GEs/g oil), α-amylase (1.35 mmol ACEs/g oil), α-glucosidase (38.84 mmol ACEs/g oil), and lipase (1.59 mmol OEs/g oil) inhibitory activities. Moreover, strong antioxidant effects were observed in antiradical (DPPH and ABTS), reducing power (CUPRAC and FRAP), total antioxidant, and metal chelating assays. Methanol extract exhibited promising DPPH radical scavenging activity (0.47 mmol TEs/g extract) and also high reducing power in CUPRAC (0.89 mmol TEs/g extract) and FRAP (0.52 mmol TEs/g extract) assays. All extracts showed low total flavonoid but high total phenolics content. Furthermore, they exhibited strong skin-care effect in tyrosinase inhibition assay. EO analysis showed the presence of germacrene D (26.7%), caryophyllene oxide (14.3%), ( E)-caryophyllene (13.8%), and spathulenol (11.3%) as the major volatile components. Results indicated that P. gaubae has promising potential for possible uses in food, cosmetic, and pharmaceutical industries due to its valuable phytoconstituents and biological activities.

Functional constituents of wild and cultivated Goji (L. barbarum L.) leaves: phytochemical characterization, biological profile, and computational studies

Goji (Lycium barbarum L.) leaves are emphasized as a functional tea or as dietary supplements. The phenolic compound profile, antioxidant, enzyme inhibitory, antimicrobial, and antimutagenic activities of leaf extracts from two selected cultivars in comparison with wild-growing plants have been evaluated. HPLC-DAD/ESI-ToF-MS analysis revealed the presence of phenolic acids and flavonoids with chlorogenic acid and rutin being the dominant compounds in the cultivated plants, whereas rutin and kaempeferol-3-O-rutinoside for wild growing ones. In particular, cv. Erma contained the highest amount of chlorogenic acid and showed a strong tyrosinase-inhibitory effect. Staphylococcus aureus, Listeria monocytogenes, and Penicillium funiculosum were the most sensitive strains when exposed to extracts from cultivated plants. Antimutagenic activity was evaluated by Ames' test. The tested extracts provided high protection against mutagenicity induced by 2-anthramine (2-AA) to Salmonella typhimurium strains TA 98 and TA 100 (max. inhibition (%) 88% and 74.2%, respectively). Overall, Goji leaves are a rich source of bioactive compounds with functional properties that need further risk/benefit evaluation when used in foods or health-promoting formulations.

Neem oil nanoemulsions: characterisation and antioxidant activity

The aim of the present work is to develop nanoemulsions (NEs), nanosized emulsions, manufactured for improving the delivery of active pharmaceutical ingredients. In particular, nanoemulsions composed of Neem seed oil, contain rich bioactive components, and Tween 20 as nonionic surfactant were prepared. A mean droplet size ranging from 10 to 100 nm was obtained by modulating the oil/surfactant ratio. Physicochemical characterisation was carried out evaluating size, ζ-potential, microviscosity, polarity and turbidity of the external shell and morphology, along with stability in simulated cerebrospinal fluid (CSF), activity of Neem oil alone and in NEs, HEp-2 cell interaction and cytotoxicity studies. This study confirms the formation of NEs by Tween 20 and Neem oil at different weight ratios with small and homogenous dimensions. The antioxidant activity of Neem oil alone and in NEs was comparable, whereas its cytotoxicity was strongly reduced when loaded in NEs after interaction with HEp-2 cells.

Optimization of Aqueous Extraction and Biological Activity of Harpagophytum procumbens Root on Ex Vivo Rat Colon Inflammatory Model

Harpagophytum procumbens has a long story of use for the treatment of inflammatory diseases. Considering both the antiinflammatory effects of H. procumbens in multiple tissues and the stability of harpagoside in artificial intestinal fluid, the aim of the present study was to explore the possible protective role of a microwave-assisted aqueous Harpagophytum extract (1-1000 μg/mL) on mouse myoblast C2C12 and human colorectal adenocarcinoma HCT116 cell lines, and isolated rat colon specimens challenged with lipopolysaccharide (LPS), a validated ex vivo model of acute ulcerative colitis. In this context, we evaluated the effects on C2C12 and HCT116 viability, and on LPS-induced production of serotonin (5-HT), tumor necrosis factor (TNF)-α, prostaglandin (PG)E₂ and 8-iso-prostaglandin (8-iso-PG)F_2α . Harpagophytum extract was well tolerated by C2C12 cells, while reduced HCT116 colon cancer cell viability. On the other hand, Harpagophytum extract reduced H₂ O₂ -induced (1 mM) reactive oxygen species (ROS) production, in both cell lines, and inhibited LPS-induced colon production of PGE₂ , 8-iso-PGF_2α , 5-HT and TNFα. Concluding, we demonstrated the efficacy of a microwave-assisted Harpagophytum aqueous extract in modulating the inflammatory, oxidative stress and immune response in an experimental model of inflammatory bowel diseases (IBD), thus suggesting a rational use of Harpagophytum in the management and prevention of ulcerative colitis in humans. Copyright © 2017 John Wiley & Sons, Ltd.

Bioactivities of Achillea phrygia and Bupleurum croceum based on the composition of phenolic compounds: In vitro and in silico approaches

This study presents the effects of the Achillea phrygia Boiss. et Bal. and Bupleurum croceum Fenzl. extracts obtained by different solvents (ethyl acetate, methanol and water) on selected enzyme inhibitory effects and antioxidant ability with screening bioactive compounds. Total and individual bioactive compounds were detected by spectrophotometric and HPLC-DAD techniques. Antioxidant abilities were evaluated by different methods including free radical scavenging (ABTS and DPPH), reducing power (CUPRAC and FRAP), phosphomolybdenum and metal chelating. Enzyme inhibitory effects were tested against cholinesterases, tyrosinase, amylase, glucosidase and lipase. Total phenolic contents were ranged from 20.52 mgGAE/g extract (B. croceum methanol extract) to 41.13 mgGAE/g extract (A. phrygia methanol extract). Generally, methanol and water extracts showed the strongest antioxidant abilities, while the ethyl acetate extracts had the most promising enzyme inhibitory effects. HPLC analysis revealed the abundance of some phenolics including rutin, quercetin, sinapic acid and chlorogenic acid, respectively. These components were also assessed using molecular modelling with the aim to study their docking properties on a set of six enzymes used in this study. Overall, these species could be suggested as valuable sources of natural-bioactive agents for developing new functional, pharmacological and health-promoting ingredients.

Structure-Antioxidative and Anti-Inflammatory Activity Relationships of Purpurin and Related Anthraquinones in Chemical and Cell Assays

Anthraquinone (9,10-anthraquinone) and several hydroxy derivatives, including purpurin (1,2,4-trihydroxyanthraquinone), anthrarufin (1,5-dihydroxyanthraquinone), and chrysazin (1,8-dihydroxyanthraquinone), were evaluated for antioxidative and anti-inflammatory activities in chemical assays and mammalian cells (murine macrophage RAW 264.7 cells). Several tests were used to assess their activities: 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical; ABTS radical cation; hydrogen peroxide scavenging; reduction of potassium ferricyanide; chelation of ferrous ions; inhibition of lipid peroxidation; inhibition of nitric oxide generation; scavenging of the intracellular hydroxyl radical; expression of NLRP3 polypeptide for inflammasome assembly; and quantitation of proinflammatory cytokine interleukin 1β (IL-1β) for inflammasome activation. The results show that purpurin, from the root of the madder plant (Rubia tinctorum L.), exhibited the highest antioxidative activity in both chemical and cultured cell antioxidant assays. The antioxidative activities of the other three anthraquinones were lower than that of purpurin. In addition, purpurin could down-regulate NLRP3 inflammasome assembly and activation, suggesting that it might protect foods against oxidative damage and prevent in vivo oxidative stress and inflammation. Structure-activity relationships and the significance of the results for food quality and human health are discussed.

Polish Yellow Sweet Clover (Melilotus officinalis L.) Honey, Chromatographic Fingerprints, and Chemical Markers

A case study of Polish Melilotus officinalis honey was presented for the first time. Gas chromatography-mass spectrometry (GC-MS) (after steam distillation, Soxhlet extraction, ultrasonic solvent extraction, and solid phase extraction (SPE)) and targeted high performance liquid chromatography with a photodiode array detector (HPLC-PAD) were applied to determine the characteristic components of honey. While ubiquitous in most honeys, carbohydrates, terpene derivatives, and phenylacetic acid dominated in the Soxhlet extracts (25.54%) and in the application of SPE (13.04%). In addition, lumichrome (1.85%) was found, and may be considered as a marker of this honey. Due to the presence of these compounds, Polish yellow sweet clover honey is similar to French lavender honeys. The major compounds determined in the methanolic extract were (+)-catechine (39.7%) and gallic acid (up to 30%), which can be regarded as specific chemical markers of the botanical origin of melilot honey. With respect to total phenolic and flavonoid contents, 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were determined spectrophotometrically. The honey exhibited a moderate antioxidant activity, typical for light honeys, which correlates well with its phenolic and flavonoid composition.

Synthesis and color properties of novel polymeric dyes based on grafting of anthraquinone derivatives onto O-carboxymethyl chitosan

Blue and red polymeric dyes were prepared by grafting anthraquinone derivatives onto O-carboxymethyl chitosan.

Chemical Fingerprint Analysis and Quantitative Analysis of Rosa rugosa by UPLC-DAD

A method based on ultra performance liquid chromatography with a diode array detector (UPLC-DAD) was developed for quantitative analysis of five active compounds and chemical fingerprint analysis of Rosa rugosa. Ten batches of R. rugosa collected from different plantations in the Xinjiang region of China were used to establish the fingerprint. The feasibility and advantages of the used UPLC fingerprint were verified for its similarity evaluation by systematically comparing chromatograms with professional analytical software recommended by State Food and Drug Administration (SFDA) of China. In quantitative analysis, the five compounds showed good regression (R² = 0.9995) within the test ranges, and the recovery of the method was in the range of 94.2%–103.8%. The similarities of liquid chromatography fingerprints of 10 batches of R. rugosa were more than 0.981. The developed UPLC fingerprint method is simple, reliable, and validated for the quality control and identification of R. rugosa. Additionally, simultaneous quantification of five major bioactive ingredients in the R. rugosa samples was conducted to interpret the consistency of the quality test. The results indicated that the UPLC fingerprint, as a characteristic distinguishing method combining similarity evaluation and quantification analysis, can be successfully used to assess the quality and to identify the authenticity of R. rugosa.

Multicomponent pattern and biological activities of seven Asphodeline taxa: potential sources of natural-functional ingredients for bioactive formulations

The current study was carried out to evaluate multicomponent pattern, biological and enzymatic activities of seven Asphodeline taxa root extracts as useful ingredients, due to the fact that these plants are commonly used as traditional food supplements in Turkish regions. The extracts were characterized for free anthraquinones and phenolics to obtain a specific chemical fingerprint useful for quality control. These analyzes were coupled to biological and enzymatic activities in order to obtain comprehensive information of the natural product. Free anthraquinones and phenolics were determined using validated HPLC-PDA methods. Antioxidant properties were determined by different procedures including free radical scavenging, reducing power, phosphomolybdenum and metal chelating assays. Ames assay was performed to evaluate mutagenic/antimutagenic properties. Enzyme inhibitory activities were tested against cholinesterase, tyrosinase, α-amylase and α-glucosidase. From the herein reported results, Asphodeline could be valuable for the production of bioactive products or food supplements for cosmetic and pharmaceutical industries.

Comparative study of biological activities and multicomponent pattern of two wild Turkish species: Asphodeline anatolica and Potentilla speciosa

The multicomponent pattern and biological characterization of plant material are essential for pharmaceutical field, in the food supplements quality control procedures and to all plant-based products. These nutrients often show valuable effects related to their consumption due to the occurrence of secondary metabolites that show useful properties on health. In this framework, researches performed on this topic play a central role for human health and drug development process. The aim of this study was to compare phenolics and free anthraquinones multicomponent pattern of two wild Turkish species: Asphodeline anatolica and Potentilla speciosa using validated high-performance liquid chromatography-photogiode array (HPLC-PDA) assays, coupled to biological evaluation. Even if some variances related to biological and enzymatic inhibition activities can be ascribed to other phytochemicals, the reported data support traditional use of Asphodeline anatolica and Potentilla speciosa roots as valuable natural font for the development of novel natural-derived drug formulations and/or food supplements with health and nutritional benefits.

Microalgae-based unsaponifiable matter as source of natural antioxidants and metal chelators to enhance the value of wet Tetraselmis chuii biomass

The present work aimed to determine the antioxidant, metal chelating and neuroprotective potential of the unsaponifiable matter (UM) of Tetraselmis chuii to be applied to a biorefinery setting. The UM obtained via saponification from crude lipids extracted from microalgal wet biomass showed a radical scavenging activity (RSA) towards the DPPH radical of 90.7±1.3% and 57.1±1.2% at a concentration of 10 and 5 mg/mL, respectively. The UM fraction also displayed metal chelating capacity at a concentration of 5 mg/mL: 58.5±1.4% and 50.9±4.0% for copper and iron, respectively. The chemical characterization of the UM revealed significant levels of total phenolics (TPC, 13.61 mg GAE/g) and carotenoids (2.45 mg/g of β-carotene, lutein and violaxanthin). Overall, the separation of the UM containing high value metabolites might significantly upgrade the total wet biomass value in a biorefinery, allowing the exploitation of a stream with relevant antioxidant and metal chelating activities.