Comprehensive Analysis of the Chemical and Bioactivity Profiles of Endemic Crataegus turcicus Dönmez in Comparison with Other Crataegus Species.

Crataegus turcicus is a plant endemic to Türkiye. For the first time, this study aimed to comparatively assess its flower-bearing branches, leaves, and fruits with other well-known Crataegus species (C. monogyna, C. pentagyna, and C. orientalis) in terms of chemical composition and bioactivity studies to evaluate its potential use as a food supplement. Firstly, the contents of total phenolics (TPC), flavonoids (TFC), proanthocyanidin (TPAC), and anthocyanin (TAC) in different plant parts of Crataegus species were evaluated. The highest TPAC was found in the hydroalcoholic extract of C. turcicus flower-bearing branches. Moreover, all plant parts had comparatively higher amounts of TPC, TFC, and TAC compared to other Crataegus species. The chemical screening by high-performance thin-layer chromatography (HPTLC) resulted that C. turcicus parts were rich with chlorogenic acid, neochlorogenic acid, quercetin and vitexin derivatives, epicatechin, procyanidin, etc., and their quantities were evaluated by high-performance liquid chromatography (HPLC). In terms of several in vitro antioxidant activity outcomes, the flower-bearing branches of C. turcicus showed the highest antioxidant activity by a 2,2-diphenyl-1-picrylhydrazyl (DPPH) test among the assessed antioxidant assays. Additionally, hydroalcoholic extracts of C. turcicus significantly decreased LPS-induced nitric oxide, tumor necrosis factor-alpha, and interleukin-6 production more potently than indomethacin (positive control). In addition to its remarkable anti-inflammatory activity, C. turcicus showed analgesic activity by reducing prostaglandin E2 levels.

Activity-Guided Isolation of Cytotoxic Non-Glycosidic Ester Iridoids from Valeriana alliariifolia Adams and Unravelling Their Cell Death Mechanisms.

The aim of this study was to isolate the cytotoxic compounds from V. alliariifolia via activity-guided isolation and to determine the mechanism of actions of the most potent ones. The crude EtOH extract as well as CHCl3 and AcOEt subextracts demonstrated remarkable cytotoxic activities against A549, MCF7, HGC27 and PC3 cancer cells. Sequential chromatographic separations on active subextracts yielded 14 secondary metabolites, including 11 iridoids (1-11) most of which belong to non-glycosidic ester iridoids, two phenylpropanoids (12 and 13) and one lignan (14). The chemical structures of purified compounds were elucidated by NMR and MS analysis. Among the isolates, 7-deisovaleroylvaltrate (3) was isolated for the first time as a natural product. According to the cytotoxic assay compounds, 2, 4-6 and 8 were found to be the potent cytotoxic compounds (IC50 <10 µM) against at least one of the tested cancer cell lines. Thus, 2, 4-6 and 8 were investigated for their effects on apoptotic, necrotic and autophagic pathways as well as cell cycle progression. They exerted anticancer activities by inducing different cell death mechanisms depending on the cancer cells. The results demonstrated that 2, 4-6 and 8 could be potential anticancer drug leads that deserve further in vivo and clinical studies on the way to discover novel natural compounds with anticancer properties.

Development of new and validated HPTLC methods for the qualitative and quantitative analysis of hyperforin, hypericin and hyperoside contents in Hypericum species.

PURPOSE: Hypericum perforatum L. (St. John's wort) is a medicinally important member of Hypericaceae. Many pharmacological activities have been mostly attributed to its hyperforin, hypericin and/or hyperoside contents. Therefore, qualitative and quantitative determinations of these ingredients are essential to justify the beneficial effects of St. John's wort on health. In the European Pharmacopoeia, the TLC and HPLC methods were given for this purpose. High performance thin layer chromatography (HPTLC) has recently become increasingly used as a suitable technique for analysing herbal drugs. This study aims to develop new and validated HPTLC methods to analyse these active components in different Hypericum spp. to find other suitable species to replace the official plant. METHODS: Three different mobile phases were developed: n-hexane-ethyl acetate (8:2) for hyperforin analysis, toluene-chloroform-ethyl acetate-formic acid (8:5:3.5:0.6) for hypericin analysis and ethyl acetate-formic acid-acetic acid-water (15:2:2:1) for hyperoside analysis. These newly developed and validated HPTLC systems were further applied to determine their concentrations in different Hypericum species. RESULTS: Hyperforin concentration was found between 6.40 to 26.40 mg/g only in H. triquetrifolium, H. scabrum and two H. perforatum samples; hypericin was detected between 0.81 and 1.41 mg/g only in H. bithynicum, H. perfoliatum, H. triquetrifolium and two H. perforatum samples; and hyperoside was identified in all tested specimens ranging from 1.01 to 9.73 mg/g. The new HPTLC methods developed and validated in the present study may ensure reliable results for the qualification and quantification of hyperforin, hypericin and hyperoside contents in Hypericum species.

Protective Effect of Nigella sativa and Nigella damascena Fixed Oils Against Aflatoxin Induced Mutagenicity in the Classical and Modified Ames Test.

The antioxidant and mutagenic/antimutagenic activities of the fixed oils from Nigella sativa (NSO) and Nigella damascena (NDO) seeds, obtained by cold press-extraction from the cultivar samples, were comparatively investigated for the first time. The antimutagenicity test was carried out using classical and modified Ames tests. The fatty acid composition of the fixed oils was characterized by gas chromatography-mass spectrometry (GC-MS) while the quantification of thymoquinone in the fixed oils was determined by UPC2 . The main components of the NSO and NDO were found to be linoleic acid, oleic acid, and palmitic acid. The results of the Ames test confirmed the safety of NSO and NDO from the viewpoint of mutagenicity. The results of the three antioxidant test methods were correlated with each other, indicating NDO as having a superior antioxidant activity, when compared to the NSO. Both NSO and NDO exhibited a significant protective effect against the mutagenicity induced by aflatoxin B1 in Salmonella typhimurium TA98 and TA100 strains. When microsomal metabolism was terminated after metabolic activation of the mycotoxin, a significant increase in antimutagenic activity was observed, suggesting that the degradation of aflatoxin B1 epoxides by these oils may be a possible antimutagenic mechanism. It is worthy to note that this is the first study to assess the mutagenicity of NSO and NDO according to the OECD 471 guideline and to investigate antimutagenicity of NDO in comparison to NSO against aflatoxin.

Influence of In Vitro Human Digestion Simulation on the Phenolics Contents and Biological Activities of the Aqueous Extracts from Turkish Cistus Species.

Oxidative stress is one of the significant precursors of various metabolic diseases such as diabetes, Parkinson's disease, cardiovascular diseases, cancer, etc. Various scientific reports have indicated that secondary plant metabolites play an important role in preventing oxidative stress and its harmful effects. In this respect, this study was planned to investigate the phenolic profile and antioxidant and antidiabetic potentials of the aqueous extracts from Turkish Cistus species by employing in vitro methods. In vitro digestion simulation procedure was applied to all extracts to estimate the bioavailability of their phenolic contents. Total phenolic, flavonoid, phenolic acid and proanthocyanidin contents were determined for all phases of digestion. In addition, changes in the quantity of the assigned marker flavonoids (tiliroside, hyperoside and quercitrin) were monitored by High-Performance Thin Layer Chromatography (HPTLC) analysis. The antioxidant activity potentials of the extracts were studied by various methods to reveal their detailed activity profiles. On the other hand, in vitro α-amylase and α-glucosidase enzymes and advanced-glycation end product (AGE) inhibitory activities of the extracts were determined to evaluate the antidiabetic potentials of extracts. The results showed that aqueous extracts obtained from the aerial parts of Turkish Cistus species have rich phenolic contents and potential antioxidant and antidiabetic activities; however, their bioactivity profiles and marker flavonoid concentrations might significantly be affected by human digestion. The results exhibited that total phenolic contents, antioxidant activities and diabetes-related enzyme inhibitions of the bioavailable samples were lower than non-digested samples in all extracts.

A New Type of Anatolian Propolis: Evaluation of Its Chemical Composition, Activity Profile and Botanical Origin.

This study was undertaken to analyze the phenolic profiles of 19 propolis samples from Turkey by using a high-performance thin-layer chromatographic (HPTLC) method in order to identify their plant origins. Furthermore, their antioxidant and antimicrobial activity profiles were comparatively evaluated. For the appraisal of antioxidant potential, total phenolic (TPC) and total flavonoid contents (TFC) of propolis samples were firstly determined and then their effects on free radicals were evaluated by FRAP, ABTS.+ , CUPRAC, DPPH. and HPTLC-DPPH. methods. Antimicrobial activity of propolis samples against Staphylococcus aureus (ATCC 6538), Pseudomonas aeruginosa (ATCC 15442), Escherichia coli (ATCC 11229) and Candida albicans ATCC 10231 were determined by disc diffusion and broth dilution methods. HPTLC fingerprinting analyses revealed that O-type (botanical origin from Populus nigra L.) was the primarily available propolis type in Turkey. Moreover, 3-O-methylquercetin (3MQ) rich propolis was identified as a new propolis type for the first time. Principal component analysis (PCA) indicated that 3MQ-type propolis differs from the O-type. Antioxidant activity studies showed that O-type of propolis possesses higher antioxidant effect than the other tested propolis types. Quercetin, caffeic acid, caffeic acid phenethyl ester (CAPE) and galangin were determined to contribute significantly to the antioxidant potential of O-type propolis among others. Propolis extracts exerted moderate antimicrobial activity against the tested microorganisms with MIC values between the ranges of 128-512 µg/mL.

Evaluation of in vitro antiprotozoal activity of Ajuga laxmannii and its secondary metabolites.

Context Some Ajuga L. (Lamiaceae) species are traditionally used for the treatment of malaria, as well as fever, which is a common symptom of many parasitic diseases. Objective In the continuation of our studies on the identification of antiprotozoal secondary metabolites of Turkish Lamiaceae species, we have investigated the aerial parts of Ajuga laxmannii. Materials and methods The aerial parts of A. laxmannii were extracted with MeOH. The H2O subextract was subjected to polyamide, C18-MPLC and SiO2 CCs to yield eight metabolites. The structures of the isolates were elucidated by NMR spectroscopy and MS analyses. The extract, subextracts as well as the isolates were tested for their in vitro antiprotozoal activities against Plasmodium falciparum, Trypanasoma brucei rhodesiense, T. cruzi and Leishmania donovani at concentrations of 90-0.123 µg/mL. Results Two iridoid glycosides harpagide (1) and 8-O-acetylharpagide (2), three o-coumaric acid derivatives cis-melilotoside (3), trans-melilotoside (4) and dihydromelilotoside (5), two phenylethanoid glycosides verbascoside (6) and galactosylmartynoside (7) and a flavone-C-glycoside, isoorientin (8) were isolated. Many compounds showed moderate to good antiparasitic activity, with isoorientin (8) displaying the most significant antimalarial potential (an IC50 value of 9.7 µg/mL). Discussion and conclusion This is the first report on the antiprotozoal evaluation of A. laxmannii extracts and isolates. Furthermore, isoorientin and dihydromelilotoside are being reported for the first time from the genus Ajuga.

Quantitative determination of phenolic compounds in propolis samples from the Black Sea Region (Türkiye) based on HPTLC images using partial least squares and genetic inverse least squares methods.

The complex chemical composition of propolis is related to the plant source to be used by honeybees. Propolis type is defined based on the plant source with the highest proportion in its composition, which is determined by chromatographic techniques as high-performance thin-layer chromatography (HPTLC). In addition to marker component identification to specify the propolis type, quantification of its proportion is also significant for prediction and reproducible pharmacological activity. One drawback for propolis marker component quantitation is that during the chromatographical analysis, not the main but the other plant sources with less proportion may cause interferences during the chemical analysis. In this study, the amounts of marker components were compared with the reference analysis data obtained by high-performance liquid chromatography (HPLC) and from HPTLC images using Partial Least Squares (PLS) and Genetic Inverse Least Squares (GILS) regression methods. Firstly, HPTLC images of propolis samples were processed by an image algorithm (developed in MATLAB) where the bands of each standard and the samples were cut same dimensional pieces as 351 × 26 pixels in height and width, respectively. Simultaneously, reference analysis of the marker components in propolis samples was performed with a validated HPLC method. Consequently, the reference values obtained from HPLC versus PLS, and GILS predicted values of the eight compounds based on the digitized HPTLC images of the chromatograms were found to be matched successfully. The results of the multivariate calibration models demonstrated that HPTLC images could be used quantitatively for quality control of propolis used as a food supplement.

Phytochemical and Bioactivity Studies on Hedera helix L. (Ivy) Flower Pollen and Ivy Bee Pollen.

Bee pollen, known as a 'life-giving dust', is a product of honeybees using flower pollen grains and combining them with their saliva secretions. Thus, flower pollen could be an indicator of the bee pollen botanical source. Identification of bee pollen sources is a highly crucial process for the evaluation of its health benefits, as chemical composition is directly related to its pharmacological activity. In this study, the chemical profiles, contents of phenolic marker compounds and pharmacological activities of Hedera helix L. (ivy) bee pollen samples from Türkiye and Slovenia, as well as ivy flower pollen grains, were compared. High-performance thin-layer chromatography (HPTLC) analyses revealed that pollen samples, regardless of where they were collected, have similar chemical profiles due to the fact that they have the same botanical origins. Marker compounds afzelin, platanoside and quercetin-3-O-ß-glucopyranosyl-(1→2)-ß-galactopyranoside, common to both bee pollen and flower pollen, were isolated from bee pollen, and their structures were elucidated by nuclear magnetic resonance (NMR) and mass spectrometry (MS). These three compounds, as well as chlorogenic acid and 3,5-dicaffeoylquinic acid (found in flower pollen), were quantified using high-performance liquid chromatography (HPLC) analyses. In vitro tests and effect-directed analyses were used to evaluate the xanthine oxidase inhibition and antioxidant activity of the marker compounds and extracts from flower pollen and bee pollen. This is the first report comparing chemical profiles and related bioactivities of the flower pollen and bee pollen of the same botanical origin, as well as the first report of the chemical profile and related bioactivities of ivy flower pollen.

Secondary metabolites from the underground parts of Valeriana sisymbriifolia Vahl. and their in vitro cytotoxic activities.

Cytotoxic activity-guided isolation studies on the underground parts of Valeriana sisymbriifolia Vahl. led to the isolation of 12 secondary metabolites including two undescribed iridoids, sisymbriifolivaltrate and sisymbriifolioside, and two unreported sesquiterpene lactones, sisymbriifolins A and B. Chemical structures of the isolates were established by extensive 1D and 2D NMR analyses as well as HR-ESI-MS. The in vitro cytotoxic activities of the extract, sub-fractions and isolates on lung (A549), breast (MCF7), gastric (HGC27) and prostate (PC3) cancer cell lines were evaluated by MTS assay. Sisymbriifolivaltrate, didrovaltrate, valtrate, 7-homovaltrate and 1-α-acevaltrate exhibited promising cytotoxic activity on MCF7 cell line with IC50 values ranging from 2.5 to 12.3 µM, while valtrate demonstrated the best cytotoxicity against A549 cells with the IC50 value of 7.5 µM. Valtrate and 7-homovaltrate were found to exert noteworthy cytotoxicity towards HGC27 cell line (IC50 values: 2.3 and 3.7 µM, respectively), whereas valtrate, 7-homovaltrate and 1-α-acevaltrate (IC50 values: 2.3-9.7 µM) were found to be potent cytotoxic against PC3 cells. Among the tested compounds, particularly valepotriate-type iridoids were found to be the main cytotoxic principles of V. sisymbriifolia.

Comprehensive estrogenic/anti-estrogenic, anticancer, mutagenic/anti-mutagenic, and genotoxic/anti-genotoxic activity studies on chemically characterized black poplar and Eurasian aspen propolis types.

Propolis is mainly composed of plant resins, and its type is named according to the primary plant origin in its composition. Identification of propolis botanical origin is essential for predicting and repeating its pharmacological activity because of the variations in chemical composition. This study aimed to compare chemical composition of black poplar (Populus nigra L.) type-propolis (PR1 and PR2) and Eurasian aspen (P. tremula L.)-type propolis (PR3) by liquid chromatography-tandem mass spectrometry (LC-MS/MS) technique and to evaluate their biological activity profiles. According to LC-MS/MS results, in addition to marked caffeic acid phenethyl ester content in PR1 and PR2, flavonoid aglycones such as pinocembrin, chrysin, pinobanksin, and galangin were found to be dominant in these samples. On the other hand, PR3 contained relatively high concentrations of phenolic acids such as ferulic acid, p-coumaric acid, and trans-cinnamic acid. The anti-estrogenic activity test showed that PR2 exerted the highest anti-estrogenic activity by inhibiting cell proliferation by 44.6%. All propolis extracts showed anticancer activity, which was justified by decreasing activity on the 3D spheroid size in a concentration-dependent manner. Besides, all extracts showed moderate or potent antimutagenic activity in Salmonella typhimurium TA98 and TA100 strains with and without metabolic activation, respectively. In addition, the Comet assay results revealed that propolis extracts have a geno-protective effect against H2O2-induced DNA damage in CHO-K1 cells at 0.625 and 1.25 µg/mL concentrations. Overall, the result of this study may help in preparing standardized propolis extracts and developing products with defined pharmacological benefits in the food supplements industry.

Chewable tablet with herbal extracts and propolis arrests Wuhan and Omicron variants of SARS-CoV-2 virus.

Prevention of COVID-19 is of paramount importance for public health. Some natural extracts might have the potential to suppress COVID-19 infection. Therefore, this study aimed to design a standardised, efficient, and safe chewable tablet formulation (with propolis and three herbal extracts) for possible prevention against two variants (Wuhan B.1.36 and Omicron BA.1.1) of SARS-CoV-2 virus and other viral infections. Green tea, bilberry, dried pomegranate peel, and propolis extracts were selected for this purpose. Cytotoxicity and antiviral activity of each component, as well as the developed chewable tablet, were examined against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus using Vero E6 cells with the xCELLigence real-time cell analyser-multiple plates system. Anti-inflammatory and analgesic activities, as well as mutagenicity and anti-mutagenicity of the chewable tablet were also analysed. Compared to the control, it was observed that the chewable tablet at concentrations of 110 and 55 µg/mL had antiviral activity rates of 101% and 81%, respectively, for the Wuhan variant and 112% and 35%, respectively, for the Omicron variant. The combination of herbal extracts with propolis extract were synergically more effective (∼7-fold higher) than that of individual extract. The present work suggests that a combination of herbal extracts with propolis at suitable concentrations can effectively be used as a food supplement for the prevention of both variants of the SARS-CoV-2 virus in the oral cavity (the first entry point of the SARS-CoV-2 virus).

New gastroprotective labdeneamides from (4S,9R,10R) methyl 18-carboxy-labda-8,13(E)-diene-15-oate.

Starting from the diterpene (4S,9R,10R) methyl 18-carboxy-labda-8,13(E)-dien-15-oate (PMD) and its 8(9)-en isomer [PMD 8(9)-en], 11 amides were prepared and assessed for a gastroprotective effect in the ethanol/HCl-induced gastric lesions model in mice. Basal cytotoxicity of the compounds was determined on the following human cell lines: normal lung fibroblasts (MRC-5), gastric epithelial adenocarcinoma (AGS), and hepatocellular carcinoma (Hep G2). All compounds are described for the first time. At the single oral dose of 0.1 mg/kg, compounds 1, 10, and 11 presented a strong gastroprotective effect, at least comparable with that of the reference compound lansoprazole at 1 mg/kg, reducing gastric lesions by 76.7, 67.7, and 77.2 %, respectively. The leucyl amide methyl ester 3, tryptophanyl amide methyl ester 5, and benzyl amide 6 of PMD presented a selective basal cytotoxicity on Hep G2 cells with IC50 values of 136.8, 105.3, and 94.2 µM, respectively, while the IC50 values towards AGS cells were 439.5, 928.0, and 937.3 µM, respectively. The three compounds did not affect fibroblast viability with IC50 values > 1000 µM. Compounds 7, 8, 10, and 11 showed no toxic effect against the three selected cell lines.

A comprehensive study to evaluate the wound healing potential of okra (Abelmoschus esculentus) fruit.

ETHNOPHARMACOLOGICAL RELEVANCE: Okra fruit (Abelmoschus esculentus (L.) Moench) has been extensively used for the treatment of skin damage and subcutaneous tissue abscess for many years in Turkish folk medicine. AIM OF STUDY: In this study, we aimed to investigate the wound healing potential of okra fruit by in vitro and in vivo experimental models in detail. Furthermore, based on the results of experiments, a wound healing formulation was developed and its activity profile was studied. MATERIALS AND METHODS: For this purpose, the phenolic, flavonoid and proanthocyanidin contents and chemical profile of aqueous and ethanolic extracts prepared from okra fruits cultivated in two different locations of Turkey, i.e. Aegean and Kilis regions, were comparatively determined and the tryptophan levels, which is known to be an influential factor in wound healing, were measured. Antioxidant activity of the okra fruit extracts was determined by DPPH test, ABTS radical scavenger activity, iron-binding capacity, total antioxidant capacity and copper reduction capacity assays. Moreover, antibacterial activity potentials of the aqueous and ethanolic extracts of okra fruits were determined. The protective effect of the extracts against H2O2-induced oxidative stress and anti-inflammatory activity were assessed in HDF (human dermal fibroblast) cells and in RAW 264.7 murine macrophages, respectively. The biocompatibility of the gel formulations prepared with the best performing extract were evaluated by human Epiderm™ reconstituted skin irritation test model. Wound-healing activity was investigated in rats by in vivo excision model and, histopathological examination of tissues and gene expression levels of inflammation markers were also determined. RESULTS: According to our findings, the aqueous and ethanolic extracts of okra fruits were found to possess a rich in phenolic content. Besides, isoquercitrin was found to be a marker component in ethanolic extracts of okra fruits. Both extracts exhibited antioxidant activity with significant protective effect against H2O2-induced damage in HDF cells by diminishing the MDA level. Also, the highest dose of ethanolic extracts has displayed a potent anti-inflammatory activity on LPS-induced RAW264.7 cells. Besides, both water and ethanolic extracts were shown to possess antimicrobial activity. On the other hand, the formulations prepared from the extracts were found non-irritant on in vitro Epiderm™-SIT. In vivo excision assay showed that tissue TGF-ß and IL-1ß levels were significantly decreased by the 5% okra ethanolic gel formulation. The histopathological analysis also demonstrated that collagenisation and granulation tissue maturation were found higher in 5% (w/v) okra ethanolic extract-treated group. CONCLUSION: 5% of okra ethanolic extract might be suggested as a potent wound healing agent based on the antimicrobial, antioxidant and anti-inflammatory tests. The proposed activity was also confirmed by the histopathological findings and gene expression analysis.

Development of propolis and essential oils containing oral/throat spray formulation against SARS-CoV-2 infection.

A broad range of evidence has confirmed that natural products and essential oils might have the potential to suppress COVID-19 infection. Therefore, this study aimed to develop an oral/throat spray formulation for prophylactic use in the oral cavity or help treatment modalities. Based on a reference survey, several essential oils, a cold-pressed oil, and propolis were selected, and cytotoxicity and antiviral activity of each component and the developed spray formulation were examined against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection using Vero E6 cells. Anti-inflammatory, antimicrobial, and analgesic activities as well as mutagenicity and anti-mutagenicity of the formulation were analysed. Forty-three phenolics were identified in both propolis extract and oral/throat spray. The spray with 1:640-fold dilution provided the highest efficacy and the cytopathic effect was delayed for 54 h at this dilution, and the antiviral activity rate was 85.3%. A combination of natural products with essential oils at the right concentrations can be used as a supplement for the prevention of SARS-CoV-2 infection.

Antiprotozoal activity of Melampyrum arvense and its metabolites.

An activity guided isolation of the H(2)O subextract of the crude extract of Melampyrum arvense L. afforded iridoid glucosides: aucubin (1), melampyroside (2), mussaenoside (3), mussaenosidic acid (4), 8-epi-loganin (5); flavonoids: apigenin (6), luteolin (7), luteolin 7-O-ß-glucopyranoside (8); a lignan glycoside dehydrodiconiferyl alcohol 9-O-ß-glucopyranoside (9); and benzoic acid (10). ß-Sitosterol (11) and a fatty acid mixture (12) were identified as the active principles of the CHCl(3) subextract. The structures of the isolates were elucidated by spectroscopic methods, while the composition of 12 was identified by GC-MS after methylation. Luteolin (7) appeared as the most active compound against Trypanosoma brucei rhodesiense and Leishmania donovani (IC(50) values 3.8 and 3.0 µg/mL). Luteolin 7-O-ß-glucopyranoside (8) displayed the best antiplasmodial activity against Plasmodium falciparum (IC(50) value 2.9 µg/mL). This is the first detailed phytochemical study on Turkish M. arvense and the first report of the antiprotozoal effect of Melampyrum species and its constituents.

Synthesis and pharmacological activity of diterpenylnaphthoquinone derivatives.

New diterpenylquinones, combining a diterpene diacid and a naphthoquinone, were prepared from junicedric acid and lapachol. The new derivatives were assessed as gastroprotective agents by the HCl-EtOH-induced gastric lesions model in mice as well as for basal cytotoxicity on the following human cell lines: Normal lung fibroblasts (MRC-5), gastric epithelial adenocarcinoma (AGS), and hepatocellular carcinoma (Hep G2). Several of the new compounds were significantly active as antiulcer agents and showed selective cytotoxicity against AGS cells.

Diabetes mellitus and phytotherapy in Turkey.

This study reports a literature review aimed to analyse various studies related to the use of phytotherapy in diabetes mellitus in Turkey in order to provide additional information for healthcare professionals. The incidence of Diabetes Mellitus is rising and many of the diabetics frequently use herbal treatments along with modern medical treatment for glycaemic control and/or improve their well-being. Several electronic databases (such as Medline and Pubmed) were searched for 1990-2010 period (till May, 2010) and 33 related articles were analysed. Many studies--mostly animal trials- have been conducted in this field. Among the herbs most-commonly used along with modern medical therapies and also in folkloric medicine, we searched for bitter melon, cinnamon, fenugreek, olive leaf, black seed and white mulberry. Studies conducted in this field have produced conflicting results and, the necessity to conduct randomized, placebo-controlled clinical human studies to develop new drugs from herbs, as in the case of metformin, still remains important. Besides, further studies are required to address the issues of standardization and quality control of existing preparations. More importantly, healthcare professionals caring for diabetic patients need to be aware of phytotherapy to incorporate phytomedicine into their practices and should undertake more responsibility in relation to these kind of therapies that are commonly-used throughout the world.

A Realistic Approach for Anti-Inflammatory, Antinociceptive and Antimutagenic Activities, and Risk Assessment of the Aqueous Extract of Platanus orientalis L. Leaves.

BACKGROUND: Oriental planetree (Platanus orientalis L.) leaf was recorded as a remedy against inflammatory problems and to stop the pain, i.e. toothache or knee pain in "The Canon of Medicines" by Avicenna and was also being documented in the Iranian Traditional Medicine. Although such a utilization has not been described in reliable sources, recently use of its leaves as herbal tea has become popular among laypeople. Previous studies have shown that only the nonpolar extract from the leaves may have such efficacy, while possible benefits when it is used as herbal tea have not been investigated. OBJECTIVE: The present study aims to reveal the possible efficacy and safety profile of aqueous extract from P. orientalis leaf. METHODS: Aqueous extract of the leaves was submitted to in vivo and in vitro tests to determine its anti-inflammatory, antinociceptive, antimutagenic activities and also reveal its safety profile. RESULTS: The aqueous extract (400 mg/kg) procured weak and non-significant anti-inflammatory and antinociceptive activities. Meanwhile, the aqueous extract demonstrated antimutagenic activity in very high concentrations. On the other hand, results of safety evaluation showed that no concern had been observed from the viewpoint of public health. CONCLUSION: Despite the popularity of the herbal tea prepared from the leaves of Oriental planetree among the people suffering joint problems to relieve pain, this study has proven that such application would not help them to alleviate their complaints when used as herbal tea.

Comparison of antioxidant and anti-inflammatory activity profiles of various chemically characterized Turkish propolis sub-types: Which propolis type is a promising source for pharmaceutical product development?

Propolis shows a great variation in its chemical content depending on the vegetation around the beehive. Determination of its botanical origin and the chemical characterization are the most important issues for the standardization and the quality evaluation for propolis samples that are intended to be used in the pharmaceutical industry. This study has focused on the identification of the botanical origin of 47 propolis samples collected from different locations in the Black Sea Region of Turkey. Firstly, palynological and chromatographic analyses were carried out. Then, the major distinguishing components were identified by high-performance thin-layer chromatography (HPTLC), or by nuclear magnetic resonance (NMR) spectroscopy, and mass spectrometry (MS) after isolation of the components. Based on the results, the samples were categorized into three main groups as black poplar-type, Euroasian aspen-type, and non-phenolic-type. Key markers of black poplar-type were assigned as phenolic acids and flavonoids, whereas lasiocarpin B and C (phenolic glycerides) were determined as markers for Euroasian aspen-type propolis. The total phenolics and flavonoid contents (TPC and TFC) and antioxidant capacities of the samples were comparatively assessed by free radical-scavenging activity (DPPH) and metal-reducing activity (CUPRAC and FRAP) methods. Additionally, HPTLC-direct bioautography was applied to determine the contribution of components to antioxidant activity. Hierarchical clustering analysis revealed similarities in TFC, TPC values, and antioxidant activity related to the sample origins' geographic proximity. The anti-inflammatory activities of the black poplar sub-type and Euroasian aspen-type propolis samples were comparatively investigated on RAW 264.7 macrophage cells. The black poplar-type propolis extract dominated by caffeic acid, caffeic acid phenethyl ester, apigenin, quercetin, kaempferol, pinocembrin, and galangin exhibited the highest anti-inflammatory and antioxidant activities. Therefore, chemically characterized black poplar-type propolis may be suggested as a good candidate to develop pharmaceutical products.