Isolation and Characterization of Acetylcholinesterase Inhibitors from Piper longum and Binding Mode Predictions.

Restoration of cholinergic function is considered a rational approach to enhance cognitive performance. Acetylcholinesterase inhibitors are still the best therapeutic option for Alzheimer's disease. The fruits of Piper longum have been used in traditional medicines for the treatment of memory loss. It was demonstrated that the dichloromethane extract of these fruits is able to inhibit acetylcholinesterase. Thus, the aim of this study was to identify the contained acetylcholinesterase inhibitors. The active zones were presented via TLC-bioautography, and five compounds were isolated in the process of a bioassay-guided phytochemical investigation. Their structures were characterized as piperine, methyl piperate, guineenisine, pipercide, and pellitorine using spectroscopy and spectrometry methods (UV, IR, MS, 1H-, and 13C-NMR). In vitro acetylcholinesterase inhibitory activities of the isolates and their IC50 values were determined via a colorimetric assay. Three of them exhibited enzyme inhibitory activities, with piperine being the most potent compound (IC50 of 0.3 mM). In order to investigate the binding mode of the tested compounds, docking studies were performed using the X-ray crystal structure of acetylcholinesterase from Tetronarce californica with the Protein Data Bank code 1EVE. The content of the active compounds in the extract was determined by a developed HPLC method. Piperine was present in the maximum quantity in the fruits (0.57%), whereas methyl piperate contained the minimum content (0.10%).

Bioassay-guided fractionation and identification of wound healing active compound from Pistacia vera L. hull extract.

ETHNOPHARMACOLOGICAL RELEVANCE: Pistachio hull has traditionally been used to treat peptic ulcer, hemorrhoids, oral and cutaneous wounds. AIM OF THE STUDY: On the basis of its traditional uses and previous pharmacological reports, a bioassay guided fractionation procedures on pistachio (Pistacia vera L.) hulls was performed to define the fractions and bioactive compound that are responsible for wound healing activity of hulls. MATERIAL AND METHODS: A bioassay-guided fractionation of the total extract (MeOH 80%) of Pistacia vera L. hulls was carried out to evaluate wound healing activity by scratch assay on NIH/3T3 murine fibroblast cells. A combination of solvent-solvent partitioning, column chromatography, preparative thin layer chromatography and crystallization were used to obtain fractions/sub-fractions and pure compound. The wound healing potential of isolated compound was examined by fibroblasts migration and proliferation using scratch assay and CFSC dilution assay, respectively. In addition, we evaluated the gene expression of some inflammatory markers which are involved in healing process using Real Time PCR. Chemical structure of active compound was elucidated by spectrometric methods. RESULTS: Due to the higher wound healing activity of CHCl3 fraction from P. vera hulls, it was fractionated by successive chromatographic techniques to yield the active compound. 3-Epimasticadienolic acid was isolated and crystallized as a white powder. This active compound (200 µg/ml) significantly increased the fibroblast proliferation and migration, resulting in reduction of the scratch area about 45%. It showed a strong inhibitory effect on gene expression of IL-6 and TNF-α, and a stimulation effect on NF-κB gene expression at the same dose. CONCLUSION: The present study supported the traditional uses of P. vera hulls for wound-healing and 3-epimasticadienolic acid showed significantly potent on wound repair.

Evaluation of anti-tyrosinase activity of Allium ursinum extracts and their metal complexes.

BACKGROUND: A. ursinum is found to contain high levels of some beneficial phenolic and poly phenolic compounds were found to be effective in scavenging DPPH radicals and tyroinase inhibition. The aim of this study was to evaluate the anti-tyrosinase and antioxidant activity of three different extracts from the ultrasound-assisted method and their metal complexes from A. ursinum to discover new candidates for food additives, cosmetic and pharmaceutical products. METHODS: Water, 70% ethanol and absolute ethanol extract of Allium ursinum and their man- ganese and zinc-complexes were characterized by FT-IR and UV-Vis spectra and their antioxidant and anti- tyrosinase activity determined using DPPH radical scavenging and mushroom tyrosinase assay. RESULTS: The antioxidant activity of the water extract was superior to other samples, while the 70% ethanol extract exhibited the highest anti-tyrosinase activity. Metal complex formation of the extracts led to a signifi- cantly lower antioxidant effect. The tyrosinase inhibition strongly related to the metal ion and extraction sol- vent. All the zinc complexes had lower anti-tyrosinase activity than their extracts, while the manganese com- plex of the water and absolute ethanol extracts exhibited higher anti-tyrosinase activity than related extracts. CONCLUSIONS: This study shows that Mn complex of A. ursinum extracts, based on the solvent extraction, could increase tyrosinase inhibition activity and could be a good candidate for intended cosmetic applications and food additives.

Data showing the optimal conditions of pre-extraction and extraction of Citrullus lanatus (watermelon) white rind to increase the amount of bioactive compounds, DPPH radical scavenging and anti-tyrosinase activity.

In this data article, we examined some of those factors such as the effect of fresh, frozen and hot air-dried sample, pH and polarity of solvent by ultrasound-assisted extraction, as a "Green Extraction" technique, to find optimal conditions for increasing the amount of total phenolic and amino acid contents from watermelon rind. Then, we considered the DPPH radical scavenging and anti-tyrosinase activity of the extracts and their association with the amount of the phenolic and amino acid contents in the samples. The obtained data were analyzed one-way ANOVA, Tukey post hoc test and Graph Pad Prism 6 (P < 0.05). Our findings revealed one of the appropriate pre-extraction and extraction conditions of watermelon white rind to achieve more antioxidant and anti-tyrosinase effects. In addition, our data show the value of watermelon white rind as inexpensive, safe whitening and anti-browning agent, which can be used in pharmaceuticals, cosmetics and food products.

Anti-Melanogenic Activity and Cytotoxicity of Pistacia vera Hull on Human Melanoma SKMEL-3 Cells.

Pistacia vera seed is a common food and medicinal seed in Iran. It's hull (outer skin) as a significant byproduct of pistachio, is traditionally used as tonic, sedative and antidiarrheal and has been shown to be a rich source of antioxidants. The aim of the present study is to evaluate the anti-melanogenic activity of the pistachio hulls in order to discover a new alternative herbal agent to treat skin hyperpigmentation disorders. In this work, antioxidant and anti-tyrosinase activity of MeOH extract from Pistacia vera hull (MPH) were evaluated in vitro, respectively, by DPPH radical scavenging and mushroom tyrosinase activity assays. Then the effect of MPH on the melanin content, cellular tyrosinase activity and cytotoxicity (MTT assay) on human melanoma SKMEL-3 cell were determined followed by 72 h incubation. The results indicated that MPH had valuable DPPH radical scavenging effect and weak anti-tyrosinase activity when compared to the well-known antioxidant (BHT) and tyrosinase inhibitor (kojic acid), respectively. MPH, at a high dose (0.5 mg/mL), showed significant cytotoxic activity (~63%) and strong anti-melanogenic effect (~57%) on SKMEL-3 cells. The effect of MPH in the reduction of melanin content may be related to its cytotoxicity. The results obtained suggest that MPH can be used as an effective agent in the treatment of some skin hyperpigmentation disorders such as melanoma.

α-Amylase inhibitory activity of some traditionally used medicinal species of Labiatae.

BACKGROUND: Natural α-amylase inhibitors of herbal origin are an attractive therapeutic approach to control post-prandial hyperglycemia via reducing the glucose release from starch and delaying carbohydrate absorption. These compounds are able to inhibit the activity of the carbohydrate hydrolyzing enzymes in the small intestine and potentially useful in control of diabetes. The enlarged Lamiaceae (Labiatae) family contains about 6,900 to 7,200 species worldwide and many species of this family possess medicinal properties and have been used traditionally for treatment of chronic illnesses including diabetes. METHODS: In the present study particular species of Labiatae family from the genera, Phlomis, Satureja, Salvia, Scutellarua, Stachys and Hymenocrater, which are growing wildly in Iran, selected to evaluate for possible in vitro α-amylase inhibitory activity, compared to acarbose as a positive control. RESULTS: The inhibitory activities of all the herbal extracts were varied from 1.9 to 18.6 (IC50, µg/mL). Additionally, the ethyl acetate extract of P. bruguieri (IC50 = 1.9 µg/mL) and the butanol extract of P. persica (IC50 = 3.6 µg/mL) exhibited the lowest IC50 values among all the species as the most potent herbal extracts, while the inhibitory activity of S. sahendica and S. macrosiphon (ethyl acetate extracts) as well as P. caucasica (butanol extract) on α-amylase enzyme was observed as weak and did not reach at least to the 50% of the enzyme inhibition level. CONCLUSIONS: Taking together, P. bruguieri and P. persica among the Phlomis species can be the promising sources of α-amylase inhibitors. However, P. rigida, S. bizantina and H. bituminosus that exhibited moderate activity can be stand on second level of interest.

Traditional uses, phytochemistry and pharmacological properties of the genus Peucedanum: a review.

ETHNOPHARMACOLOGICAL RELEVANCE: The genus Peucedanum (Apiaceae) comprising more than 120 species is widely distributed in Europe, Asia and Africa. The ethnopharmacologial history of this genus indicated that some extracts of aerial and underground parts of several Peucedanum species have been used in folk medicine for treatment of various conditions, such as cough, cramps, pain, rheumatism, asthma and angina. This review focuses on ethnopharmacological uses of Peucedanum species, as well as the phytochemical, pharmacological and toxicological studies on this genus. Through this review, I intend to highlight the known and potential effects of the Peucedanum species or their isolated compounds and show which traditional medicine uses have been supported by pharmacological investigations. METHODS: Information on the Peucedanum species was collected from scientific journals, books, thesis and reports via a library and electronic search (using Google Scholar, Pubmed, Scopus, Web of Science and ScienceDirect). This review covers the available literature from 1970 to the end of September 2013. RESULTS: Although, there are about 120 species in this genus, so far many species have received no or little attention and most of pharmacological studies were performed on just about 20 species. Many phytochemical investigations on this genus confirmed that Peucedanum species are rich in essential oils and coumarins. The present review article shows that Peucedanum species have a wide spectrum of pharmacological activities and the most reported activities of Peucedanum plants come back to the presence of coumarins, flavonoids, phenolics and essential oils. CONCLUSIONS: The present review confirms that some Peucedanum species have emerged as a good source of the traditional medicine for treatment of inflammation, microbial infections, cardiopulmonary diseases and provides new insights for further investigations on isolated compounds, especially on praeruptorins, to find novel therapeutics and aid drug discovery. However, for using Peucedanum species to prevent and treat various diseases, additional pharmacological studies to find the mechanism of action, safety and efficacy of them before starting clinical trials are required.

Quantification of verbascoside in medicinal species of Phlomis and their genetic relationships.

BACKGROUND: The genus Phlomis (Lamiaceae) is introduced by its valuable medicinal species, of which 17 species are growing wildly and ten of them are exclusively endemic of Iran. The main phytochemical characteristic of this genus is presence of iridoid glycosides including ipolamide, auroside, lamiide and also phenylethanoids such as verbascoside (acetoside) found in Lamiales order.Due to the broad range of biological and pharmacological activities of verbascoside and lack of any report on quantification of this compound within Iranian species of Phlomis, we conducted a research to achieve two main goals, finding a genetic biodiversity by RAPD (Randomly Amplified Polymorphic DNA), as well as detecting and quantifying verbascoside in nine species of Phlomis growing wildly in Iran. RESULTS: The results showed that various samples of P.olivieri possess different genetic distances from each other. Also, various species of P.olivieri display close relationships to P.anisodonta and P. persica. Phytoanalysis of Phlomis species by means of TLC scanner using verbascoside as a phytochemical marker showed that the highest concentration of verbascoside was found in P. anisodonta, however, P. bruguieri and P. olivieri (from Mazandaran) were in the second and third places. Interestingly, the lowest concentration of verbascoside was detected in P. olivieri (from Azerbayjan), exhibiting the effect of various growing areas and conditions on the measured levels of this compound. CONCLUSIONS: verbascoside can be found in various species of Iranian Phlomis, of which P. anisodonta, P. bruguieri and P. olivieri might be the best choices. In addition, although the concentration of verbascoside in these plants may be affected by the growing areas and conditions, there are a good agreement between genetic relations and verbascoside levels.

Biological activities and pharmacokinetics of praeruptorins from Peucedanum species: a systematic review.

Praeruptorins belonging to the angular-type pyranocoumarins are bioactive constituents that have been isolated from some Peucedanum species such as P. praeruptorum, which is used in traditional Chinese medicine for treatment of cold, cough, upper respiratory infections, and so forth. Many reports have demonstrated that the beneficial pharmacological effects of P. praeruptorum root on cardiovascular, pulmonary, immune, and nervous system diseases were attributed to the presence of praeruptorins. The aim of this review is to explain the recent efforts of scientists in pharmacological screening of natural and synthetic praeruptorin derivatives, studying the mechanisms of some praeruptorins action, pharmacokinetics, toxicity, and relevant structure-activity relationships. Based on reported data about the pharmacological properties of praeruptorins and semisynthetic derivatives of them, it is hopeful that in the near future more studies focus on the discovery of the new application and therapeutic uses of these bioactive compounds and understanding the specific mechanisms of them. The present discusses the reports on molecular and biological activities of praeruptorins of the genus Peucedanum, from 1976 onwards.

Tyrosinase inhibitor and radical scavenger fractions and isolated compounds from aerial parts of Peucedanum knappii Bornm.

In this study, we investigated tyrosinase inhibitory and radical scavenger activities of the hydroalcoholic extract from Peucedanum knappii Bornm aerial parts, together with its fractions. The EtOAc fraction showed the highest antioxidant and anti-tyrosinase activity was selected for the isolation and identification of major active compound(s). Two flavonol glycosides, named rhamnetin-3-O-ß-D-glucopyranoside (1) and isorhamnetin-3-O-ß-D-glucopyranoside (2) were isolated from the EtOAc fraction. Compound 1 showed the most active radical scavenging and potential anti-tyrosinase activity with SC50 values of 2.9 µg mL(-1) on the DPPH test and IC50 27.95 µg mL(-1) in mushroom tyrosinase method. Therefore, isolated flavonoids from P. knappii can be considered as antioxidant and effective tyrosinase inhibitors.

Iranian medicinal plants for diabetes mellitus: a systematic review.

In the Iranian traditional medicine a significant usage of herbs is promoted for their anti-diabetic activity. The aim of this review to assess the efficacy of glucose lowering effects of medicinal plants cultivated in Iran. An electronic literature search of MEDLINE, Science Direct, EMBASE, Scopus, Web of Science, Cochrane Library Database, Ebsco and Google Scholar from database inception conducted up to May 2012. A total of 85 studies (18 humans and 67 animals) examining 62 plants were reviewed. The quality of Randomized Controlled Trials (RCTs) assessed by using the Jadad scale. Among the RCTs studies, the best results in glycemic control was found in Aloe vera, Citrullus colocynthus, Plantago ovata, Silybum marianum, Rheum ribes and Urtica dioica. The majority of plants that have been studied for antidiabetic activity showed promising results. However, efficacy and safety of the most plants used in the treatment of diabetes are not sufficient.

Simultaneous determination of parathion, malathion, diazinon, and pirimiphos methyl in dried medicinal plants using solid-phase microextraction fibre coated with single-walled carbon nanotubes.

A reliable and sensitive headspace solid-phase microextraction gas chromatography-mass spectrometry method for simultaneous determination of different organophosphorus pesticides in dried medicinal plant samples is described. The analytes were extracted by single-walled carbon nanotubes as a new solid-phase microextraction adsorbent. The developed method showed good performance. For diazinon and pirimiphos methyl calibration, curves were linear (r(2) ≥ 0.993) over the concentration ranges from 1.5 to 300 ng g(-1), and the limit of detection at signal-to-noise ratio of 3 was 0.3 ng g(-1). For parathion and malathion, the linear range and limit of detection were 2.5-300 (r(2) ≥ 0.991) and 0.5 ng g(-1), respectively. In addition, a comparative study between the single-walled carbon nanotubes and a commercial polydimethylsiloxane fibre for the determination of target analytes was carried out. Single-walled carbon nanotubes fibre showed higher extraction capacity, better thermal stability (over 350 °C), and longer lifespan (over 250 times) than the commercial polydimethylsiloxane fibre. The developed method was successfully applied to determine target organophosphorus pesticides in real samples.

Levels of organophosphorus pesticides in medicinal plants commonly consumed in Iran.

The frequent occurrence of pesticide residues in herbal materials was indicated by previous studies. In this study, the concentration of some of the organophosphorus pesticides including parathion, malathion, diazinon and pirimiphos methyl in different kinds of medicinal plants were determined. The samples were collected randomly from ten local markets of different areas of Iran. At the detection limit of 0.5 ng g-1, parathion and pirimiphos methyl were not detected in any of the samples. Some amounts of malathion and diazinon were found in Zataria, Matricaria chamomile, Spearmint and Cumin Seed samples while, the concentrations of target organophosphorus pesticides in Borage samples were below the detection limits of the methods which could be a result of intensive transformation of organophosphorus pesticides by Borage. In addition the organophosphorus pesticides were detected in all of the samples below the maximum residue levels (MRLs) proposed by the international organizations.

Effect of Phlomis persica on glucose levels and hepatic enzymatic antioxidants in streptozotocin-induced diabetic rats.

Methanol extract of the aerial parts of Phlomis persica Boiss. (Lamiaceae) (PPE) was studied to evaluate the effects of antidiabetic potential, by measuring fasting blood glucose, insulin, total antioxidant power (TAP), using ferric reducing antioxidant power (FRAP), lipid peroxidation (using thiobarbituric acid reactive substances, TBARS), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) on streptozotocin-induced diabetes in rats. Male Wistar rats were randomly divided into five groups of six animals each. Oral administration of PPE at doses of 100 and 200 mg/kg once a day for 10 days resulted in a significant reduction in fasting blood glucose and an increase in serum insulin levels, in comparison with diabetic control group. It also prevented diabetes-induced loss in body weight. Hepatic TAP increased and TBARS decreased following PPE treatments. The extract at 100 and 200 mg/kg increased the activity of hepatic SOD, CAT, and GPx in diabetic rats. It is concluded that PPE has antidiabetic potential that is comparable with glibenclamide. In conclusion, the results of the present study show positive effects of P. persica on experimental diabetes and thus the antidiabetic effect of PPE is related to its potential to inhibit hepatocellular oxidative stress.

Antidiabetic effect of Phlomis anisodonta: effects on hepatic cells lipid peroxidation and antioxidant enzymes in experimental diabetes.

The present study investigated the effects of aerial parts of Phlomis anisodonta methanolic extract (PAE) on streptozotocin (STZ)-induced diabetic rats by measuring fasting blood glucose, serum insulin, change in body weight, ferric reducing antioxidant power (FRAP), lipid peroxidation (LPO), and liver antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). Male Wistar rats were randomly divided into six groups of six animals. Treatment of diabetic rats with oral administration of PAE at doses of 100, 200 and 400 mg kg(-1) for 10 days resulted in a significant reduction in fasting blood glucose, and an increase in serum insulin levels in comparison with diabetic control group. PAE also protected rats from STZ-induced loss in body weight. Hepatic FRAP increased and LPO in diabetic rats decreased after treatment by PAE at doses of 200 and 400 mg kg(-1). PAE-treated diabetic rats at three doses indicated a significant increase in hepatic SOD, CAT, and GPx activities. These results suggest that PAE is beneficial in the control of diabetes by reduction of blood glucose and increasing insulin levels and combating oxidative stress by activation of hepatic antioxidant enzymes.

Antinociceptive effect of Phlomis olivieri Benth., Phlomis anisodonta Boiss. and Phlomis persica Boiss. total extracts.

In this study total extracts of three species of Phlomis (Lamiaceae), Phlomis olivieri, Phlomis anisodonta and Phlomis persica were tested for their antinociceptive effects using the visceral writhing test model in mice. Doses of 50, 100 and 150 mg kg(-1) of total extracts from three species of Phlomis were administered intraperitoneally 30 min before acetic acid 0.7% injection. The total extracts of P. olivieri, P. anisodonta and P. persica, respectively at doses of 150, 150 and 100 mg kg(-1), showed significant antinociceptive effects as indicated by 60.5, 54.3 and 56.7% (P<0.001) reduction of writhes, respectively in comparison to control. Results also showed that antinociceptive properties of P. olivieri, P. anisodonta and P. persica with ED(50) values of 88.21, 123.62 and 59.24 mg kg(-1), respectively, are comparable to that of indomethacin (5 mg kg(-1)). Preliminary phytochemical analysis by thin layer chromatography using specific reagents indicated the presence of iridoid glycosides and phenolic compounds such as flavonoid and phenylpropanoid glycosides in examined total extracts. The antinociceptive properties of examined total extracts could possibly be related to presence of iridoid glycosides and phenolic compounds.