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.

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.

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.

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.