Cytotoxic abietane-type diterpenoids from roots of Salvia spinosa and their in Silico pharmacophore modeling.

The roots of Salvia spinosa L. (Lamiaceae) were extracted with hexane, dichloromethane (DCM) and ethyl acetate. The DCM extract exhibited cytotoxic activity (IC50 32.7 µg/mL) against MFC-7 breast cancer cell line in MTT colorimetric bioassay. Ferruginol (1), taxodione (2), 12-deoxy-6-hydroxy-6,7-dehydroroyleanone (3), 14-deoxycoleon U (4), 15-deoxyfuerstione (5) and taxodone (6) were isolated from the DCM roots extract. Their structures were elucidated by a combination of spectroscopic analyses including EIMS and 1H- and 13C NMR spectra. The cytotoxicity of compound 3 was determined against MCF-7 and K562 cell lines and compared with the other compounds. A pharmacophore model was built based on potent input compounds to resolve important pharmacophore features responsible for cytotoxic activity of the isolated compounds.

Dammarane-type triterpenoid saponins from Salvia russellii Benth.

Three undescribed dammarane-type saponins, russelliinosides A-C, together with a common sterol (ß-sitosterol), an abietane diterpenoid (18-hydroxyferruginol), two oleane triterpenoids (daturaolone and oleanolic acid), an ursane triterpenoid (ursolic acid) as well as three 5-hydroxyflavones (cirsimaritin, eupatorin, and salvigenin) were isolated from a dichloromethane extract of the aerial parts of Salvia russellii Benth. The chemical structures of the aforementioned compounds were characterized, using detailed spectroscopic analyses, including high-resolution mass spectrometry and 1D and 2D NMR (1H-1H COSY, TOCSY, HSQC, HMBC and NOESY) spectroscopy as well as physicochemical properties. Cytotoxic effects of S. russellii extract and the three isolated russelliinosides were tested against MCF-7 human breast and A549 lung cancer, as well as non-cancer NIH/3T3 cells using MTT reduction assay. Russelliinosides A and B exhibited cytotoxic activities with IC50 values of 7.1 and 30.7 µg/ml against MCF-7 and 33.9 and 69.4 µg/ml against A549 cells, respectively, while russelliinoside C did not show cytotoxicity against cancer cells. On the other hand, russelliinoside A showed an IC50 value of 31.5 µg/ml against NIH/3T3 cells, while russelliinosides B and C had no effect on the viability of these non-cancer cells.

Antidiabetic and cytotoxic polyhydroxylated oleanane and ursane type triterpenoids from Salvia grossheimii.

Two polyhydroxylated oleanane and seven ursane triterpenoids were isolated from aerial parts of Salvia grossheimii. The chemical structures of the undescribed triterpenoids (1-6) were characterized using 1 and 2 D NMR and ESI-MS spectral data as; 2α, 3ß, 11α -trihydroxy-olean-12- ene (1), 2α, 3ß, 11α-trihydroxy-olean-18-ene (2), 2α- acetoxy-urs-12-ene-3ß, 11α, 20ß-triol (3), 3-keto-urs-12-ene-1ß, 11α, 20ß -triol (4), 2α, 3ß-diacetoxy-urs-12-ene-1ß, 11α, 20ß -triol (5), and 3ß-acetoxy-urs-12-ene-1ß, 11α, 20ß -triol (6). All compounds were evaluated for the in vitro α-glucosidase inhibitory and cytotoxic activities against MCF-7 human cancer cell line. Compounds 1, 2, 4, and 6 showed in vitro α-glucosidase inhibitory activity with IC50 = 43.6-198.4 µM, which were more potent than the antidiabetic medicine, acarbose. The remaining compounds; 3, and 7-9 showed potent cytotoxic activity (IC50 = 6.2-31.9 µM) against the cancerous cell line, while the potent α-glucosidase inhibitors were inactive. Molecular docking analysis and kinetic studies were applied to investigate the structure activity relationships and mechanisms of the human and Saccharomyces cerevisiae α-glucosidase inhibitory of the purified compounds. Comparing the high cytotoxicity and α-glucosidase inhibitory of the oleanane and ursane type triterpenoids suggest them as potential lead compounds for further research in anticancer and antidiabetic research.

Ecological Roles and Biological Activities of Specialized Metabolites from the Genus Nicotiana.

Species of Nicotiana grow naturally in different parts of the world and have long been used both medicinally and recreationally by human societies. More recently in our history, Nicotiana tabacum has attracted interest as one of the most economically important industrial crops. Nicotiana species are frequently investigated for their bioactive natural products, and the ecological role of their specialized metabolites in responses to abiotic stress or biotic stress factors like pathogens and herbivores. The interest of tobacco companies in genetic information as well as the success of a few wild tobacco species as experimental model organisms have resulted in growing knowledge about the molecular biology and ecology of these plants and functional studies of the plant's natural products. Although a large number of reviews and books on biologically active natural products already exists, mostly from N. tabacum, we focus our attention on the ecological roles and biological activity of natural products, versus products from cured and processed material, in this Review. The studied compounds include alkaloids, aromatic compounds, flavonoids, volatiles, sesquiterpenoids, diterpenes alcohols, and sugar esters from trichomes of the plants, and recently characterized acyclic hydroxygeranyllinalool diterpene glycosides (HGL-DTGs). In this Review (1800s-2017), we describe the above-mentioned classes of natural products, emphasizing their biological activities and functions as they have been determined either in bioassay-guided purification approaches or in bioassays with plants in which the expression of specific biosynthetic genes has been genetically manipulated. Additionally, a review on the history, taxonomy, ecology, and medicinal application of different Nicotiana species growing around the globe presented in this Review may be of interest for pharmacognosists, natural products, and ecological chemists.

Comparative genomics reveals high biological diversity and specific adaptations in the industrially and medically important fungal genus Aspergillus.

BACKGROUND: The fungal genus Aspergillus is of critical importance to humankind. Species include those with industrial applications, important pathogens of humans, animals and crops, a source of potent carcinogenic contaminants of food, and an important genetic model. The genome sequences of eight aspergilli have already been explored to investigate aspects of fungal biology, raising questions about evolution and specialization within this genus. RESULTS: We have generated genome sequences for ten novel, highly diverse Aspergillus species and compared these in detail to sister and more distant genera. Comparative studies of key aspects of fungal biology, including primary and secondary metabolism, stress response, biomass degradation, and signal transduction, revealed both conservation and diversity among the species. Observed genomic differences were validated with experimental studies. This revealed several highlights, such as the potential for sex in asexual species, organic acid production genes being a key feature of black aspergilli, alternative approaches for degrading plant biomass, and indications for the genetic basis of stress response. A genome-wide phylogenetic analysis demonstrated in detail the relationship of the newly genome sequenced species with other aspergilli. CONCLUSIONS: Many aspects of biological differences between fungal species cannot be explained by current knowledge obtained from genome sequences. The comparative genomics and experimental study, presented here, allows for the first time a genus-wide view of the biological diversity of the aspergilli and in many, but not all, cases linked genome differences to phenotype. Insights gained could be exploited for biotechnological and medical applications of fungi.

Phytochemical Investigation on Euphorbia macrostegia (Persian wood spurge).

Euphorbia macrostegia or Persian wood spurge is one of the seventeen endemic plants of this genus in Iran. Three triterpenoids, 24-methylenecycloartan-3ß-ol (1), butyrospermol (2) and cycloartenol (3) and three diglycerides, 1,2-di-O-α-linolenoyl-sn-glycerol (4), 1-O-linoleoyl-3-O-palmitoyl-sn-glycerol (5) and 1-O-α-linolenoyl-2-O-palmitoyl-sn-glycerol (6) were isolated from the hexane soluble part of methanol-dichloromethane extracts of the aerial parts of Euphorbia macrostegia Boiss. The structures of all compounds were elucidated using different spectroscopy methods including, (1)H NMR, (13)C NMR, HSQC, HMBC, EI-MS and IR. The triterpenes and the unsaturated fatty acids moieties of the diglycerides isolated from the plant were reported previously to have analgesic, anticancer, bactericidal and antifungal activity. Here, we show that E. macrostegia is a new source for the above mentioned biologically active compounds.

Carthamus, Salvia and Stachys species protect neuronal cells against oxidative stress-induced apoptosis.

CONTEXT: Finding effective therapies for neurodegenerative diseases is of utmost importance for the aging population. Plants growing in Iran are rich sources of antioxidants and active phytochemicals. OBJECTIVE: The protective capacity of plants, with a special focus on those with reported antioxidant or neuroprotective potential or nervous system-related applications in folk medicine, was tested against oxidative stress-induced apoptosis. MATERIALS AND METHODS: Aerial parts of 20 plants including Carthamus, Salvia, and Stachys species were extracted with 80% methanol and dichloromethane and preincubated with neuronal PC12 cells for 3 h. Oxidative stress and apoptosis were induced by hydrogen peroxide (75 µM, 1 h exposure). Cell viability and intracellular reactive oxygen species (ROS) were measured by MTT and 2',7'-dichlorofluorescein-diacetate (DCFH-DA) assays, respectively, while apoptosis was determined by annexin V-FITC/propidium iodide staining by a flow cytometer. RESULTS: Eighty percent methanol extracts of Carthamus oxyacantha Bieb. (Asteraceae), Salvia santolinifolia Boiss. (Lamiaceae), and Salvia sclarea L. (Lamiaceae) at the concentration of 100 µg/ml showed significant neuroprotection in the MTT assay by 38.7, 34.7, and 39.5%, respectively, and inhibited intracellular ROS by 48.6, 61.9, and 61.4%, respectively. The first two extracts also significantly inhibited apoptosis. Dichloromethane extracts of C. oxyacantha and Stachys pilifera Benth. (Lamiaceae) at the concentration of 25 µg/ml showed neuroprotection by 27.5 and 26.5%, respectively, and inhibited ROS by 44.5 and 39.4%, respectively. CONCLUSION: The above-mentioned plants seem to have important biological activities and their further study may lead to the discovery of new natural therapeutics useful against disorders such as Alzheimer and Parkinson diseases.

Cytotoxic, antioxidant and antimicrobial effects of nine species of woundwort (Stachys) plants.

CONTEXT: Woundwort (Stachys) plants from the Lamiaceae family have been used in folk medicine for various purposes. OBJECTIVE: This study was designed to analyze cytotoxic, antioxidant and antimicrobial activities of Stachys plants, because these fields have extensively benefited of drug discovery from natural sources. MATERIALS AND METHODS: Nine Stachys plants were collected from different regions of Iran. Cytotoxic activities of methanol, 80% methanol and dichloromethane (DCM) extracts of these plants were assessed on three human cancer cell lines (HL-60, K562 and MCF-7 cells) with the MTT assay, while antioxidant and antimicrobial activities were determined on methanol extracts by DPPH and nutrient broth micro-dilution assays, respectively. RESULTS: DCM extract of St. pilifera Benth. had the lowest IC50 in three cancer cell lines ranging from 33.1 to 48.2 µg/ml, followed by the 80% methanol extract of St. persica S.G.Gmel. ex C.A.Mey. (IC50 range: 62.1-104.1 µg/ml) and DCM extract of St. byzantina C. Koch (IC50 range: 62.7-131.0 µg/ml). St. byzantina. St. lavandulifolia Vahl., St. acerosa Boiss., St. obtusicrena Boiss. and St. persica showed lowest IC50 values in the DPPH scavenging assay (135.1, 162.6, 164.7, 169.4 and 172.4 µg/ml, respectively), while their total phenolic contents were 23.9, 18.2, 18.6, 20.4, 27.8 mg equivalent of gallic acid in 1 g dry plant, respectively. The methanol extracts of St. byzantina and St. persica inhibited all six tested Gram-negative and Gram-positive bacterial strains. CONCLUSION: Various Stachys species (especially St. byzantina and St. persica) are valuable sources of natural compounds with important biological properties.

Cytotoxic, antioxidant and antimicrobial activities and phenolic contents of eleven salvia species from iran.

The plants of the genus Salvia synthesize several types of secondary metabolites with antimicrobial, cytotoxic, and radical scavenging activities and are used in the folk medicine of different countries. Eleven Salvia species including S. aegyptiaca, S. aethiopis, S. atropatana, S. eremophila, S. hypoleuca, S. limbata, S. nemorosa, S. santolinifolia, S. sclarea, S. syriaca, and S. xanthocheila were collected from different localities in Iran and screened for their cytotoxic activity using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay. The antioxidant potential and total phenol contents of the plant extracts were assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and Folin- Ciocalteu reagent respectively and finally antimicrobial activity of the above extracts were determined by using agar disc diffusion (ADD) and nutrient broth micro-dilution (NBMD) bioassays. Cytotoxic activity of methanol, 80% methanol and dichloromethane extracts of these plants were assessed on 3 human cancer cell lines. All of the extracts of S. eremophila and S. santolinifolia were active at IC50 values of 10.5-75.2 µg extract/mL, while the methanol and dichloromethane extracts of S. limbata, S. hypoleuca and S. aethiopis showed considerable cytotoxic activity against the tested cell lines. Among the tested plants for their antioxidant activity, S. nemorosa, S. atropatana, S. santolinifolia, and S. eremophila were the most active radical scavengers with higher total phenol contents while, S. limbata, S. xanthocheila and S. aegyptiaca were the weakest ones. The methanol extracts of S. santolinifolia, S. eremophila, S. sclarea and S. limbata inhibited the growth of all tested bacterial strains.