Antitumor evaluation of two selected Pakistani plant extracts on human bone and breast cancer cell lines.

BACKGROUND: The medicinal plants Vincetoxicum arnottianum (VSM), Berberis orthobotrys (BORM), Onosma hispida (OHRM and OHAM) and Caccinia macranthera (CMM) are used traditionally in Pakistan and around the world for the treatment of various diseases including cancer, dermal infections, uterine tumor, wounds etc. The present study focuses on the investigation of the selected Pakistani plants for their potential as anticancer agents on human bone and breast cancer cell lines in comparison with non-tumorigenic control cells. METHODS: The antitumor evaluation was carried out on human bone (MG-63, Saos-2) and breast cancer cell lines (MCF-7, BT-20) in contrast to non-tumorigenic control cells (POB, MCF-12A) via cell viability measurements, cell cycle analysis, Annexin V/PI staining, microscopy based methods as well as migration/invasion determination, metabolic live cell monitoring and western blotting. RESULTS: After the first initial screening of the plant extracts, two extracts (BORM, VSM) revealed the highest potential with regard to its antitumor activity. Both extracts caused a significant reduction of cell viability in the breast and bone cancer cells in a concentration dependent manner. The effect of VSM is achieved primarily by inducing a G2/M arrest in the cell cycle and the stabilization of the actin stress fibers leading to reduced cell motility. By contrast BORM's cytotoxic properties were caused through the lysosomal-mediated cell death pathway indicated by an upregulation of Bcl-2 expression. CONCLUSIONS: The antitumor evaluation of certain medicinal plants presented in this study identified the methanolic root extract of Berberis orthobotrys and the methanolic extract of Vincetoxicum arnottianum as promising sources for exhibiting the antitumor activity. Therefore, the indigenous use of the herbal remedies for the treatment of cancer and cancer-related diseases has a scientific basis. Moreover, the present study provides a base for phytochemical investigation of the plant extracts.

Chemical and antimicrobial studies on the essential oil from Salvia santolinifolia Boiss.

In view of the reputation of genus Salvia in folklore medicine and its abundance in our region, the chemical composition and antimicrobial activity of essential oil from S. santolinifolia Boiss. was analyzed. Chemical analysis, using gas chromatography and gas chromatography mass spectrometry, retention indices and C-13 nuclear magnetic resonance spectroscopy has resulted in identification of 116 constituents, comprising about 97% of the total constituents. Out of these 116, 78 constituents are hitherto unreported from this source. The species belongs to α-pinene chemotype. In antibacterial assay, gram negative gastropathogens (Shigella boydii, S. flexneri, S. dysenteriae, Vibrio cholerae); causative agent of urinary tract infection (Proteus mirabilis and P. vulgaris) and pneumonia (Klebsiella pneumoniae) were found sensitive to this essential oil while Corynebacteria species and Staphylococcus epidermidis were significantly inhibited in antibacterial assay against gram positive bacteria. Clinical and Laboratory Standards Institute protocol was used for determining antimicrobial activity. Thus the essential oil from this species can be utilized as potential chemotherapeutic agent.

Diversonol and blennolide derivatives from the endophytic fungus Microdiplodia sp.: absolute configuration of diversonol.

Chemical investigation of the fungal strain Microdiplodia sp. isolated from the shrub Lycium intricatum led to the isolation of four new compounds: a hexahydroxanthone (2), a 2,3-dihydrochroman-4-one (3), a 7-oxoxanthone derivative (4), and a 1,4-oxazepan-7-one (5). The relative configurations of the new compounds were determined by intensive NMR investigations, notably NOESY experiments at different temperatures. The absolute configurations of the well-known fungal metabolite diversonol (1) and of other xanthone derivatives (3, 4) were established by means of TDDFT ECD calculations. Most of the metabolites were biologically active, with antibacterial activity against Legionella pneumophila and/or antifungal activity against Microbotryum violaceum.

Structure elucidation of two new unusual monoterpene glycosides from Euphorbia decipiens, by 1D and 2D NMR experiments.

Two new unusual monoterpene glycosides, (Z)-3,6-dimethyl-3-(ß-D-O-glucosylmethylene)cyclohept-4-ene-1-one (1) and 3,6-dimethyl-3-(ß-D-O-glucosylmethylene)cycloheptanone (2) have been isolated along with five known compounds, 3-hydroxy-4-methoxybenzoic acid, 6,7-dihydroxycoumarin, luteolin, apigenin 5-O-αl-L-rhamnoside, and pinocembrin-7-O-rutinoside from ethyl acetate extract of Euphorbia decipiens. The structures of the isolated compounds were elucidated by extensive 1D- and 2D-NMR, and mass spectroscopic analyses.

Investigation of antitussive and toxicological activity of Ballota limbata in mice.

CONTEXT: Ballota limbata Benth. (Lamiaceae) (syn, Otostegia limbata Hook.f.) is a species grown in the North West Frontier Province and the lower hills of West Punjab, Pakistan. Ballota species are renowned for their antispasmodic, antiulcer, diuretic, vermifuge, and especially sedative effects. However, little is known about the biological activity of B. limbata. OBJECTIVE: Evaluation of antitussive activity and safety profile of dried B. limbata extract. MATERIALS AND METHODS: Whole air-dried plants were partitioned with various solvents and the butanol fraction was subjected to antitussive evaluation using a sulfur dioxide (SO(2))-induced cough model in mice. Codeine and dextromethorphan were used as positive control. Safety profile of the testing material was established using standard toxicity tests. RESULTS: B. limbata extract inhibited cough provoked by SO(2) gas in mice in a dose-dependent manner. The extract exhibited maximum protection against SO(2)-induced cough after 60 min of administration. B. limbata offered maximum cough suppressive effects, that is, number of coughs during 60 min was 11.66 ± 1.2 (mean ± SEM), after s.c. administration of 800 mg/kg, as compared with codeine 10 mg/kg, s.c., dextromethorphan 10 mg/kg, s.c., and saline showing a frequency of cough of 11.75 ± 1.18, 12.25 ± 0.83, and 46.25 ± 1.52, respectively. LD(50) value of B. limbata was greater than 5000 mg/kg. No sign of neural impairment was observed at antitussive doses and the extract has been well-tolerated at higher doses. DISCUSSION AND CONCLUSION: This study demonstrates that the extract of B. limbata has shown strong cough suppressive effect in mice without yielding any notable toxicity.

Brauhenefloroside E and F; acylated flavonol glycosides from Stocksia brauhica Linn.

Two new acylated flavonol glycosides, 3-O-{[2-O-beta-D-glucopyranosyl]-3-[O-beta-D-glucopyranosyl]-4-[(6-O-p-coumaroyl)-O-beta-D-glucopyranosyl]}-alpha-L-rhamnopyranosyl-kaempferol 7-O-alpha-L-rhamnopyranoside and 3-O-{2-[(6-O-p-coumaroyl)-O-beta-D-glucopyranosyl]-3-[O-beta-D-glucopyranosyl]-4-[(6-O-p-coumaroyl)-O-beta-D-glucopyranosyl]}-alpha-L-rhamnopyranosyl-kaempferol 7-O-alpha-L-rhamnopyranoside, trivially named as brauhenefloroside E (1) and F (2), respectively, were isolated from the fruits of Stocksia brauhica and their structures were elucidated using spectroscopic methods, including 2D NMR experiments.

Charge and exciton dynamics of OLEDs under high voltage nanosecond pulse: towards injection lasing.

Electrical pumping of organic semiconductor devices involves charge injection, transport, device on/off dynamics, exciton formation and annihilation processes. A comprehensive model analysing those entwined processes together is most helpful in determining the dominating loss pathways. In this paper, we report experimental and theoretical results of Super Yellow (Poly(p-phenylene vinylene) co-polymer) organic light emitting diodes operating at high current density under high voltage nanosecond pulses. We demonstrate complete exciton and charge carrier dynamics of devices, starting from charge injection to light emission, in a time scale spanning from the sub-ns to microsecond region, and compare results with optical pumping. The experimental data is accurately replicated by simulation, which provides a robust test platform for any organic materials. The universality of our model is successfully demonstrated by its application to three other laser active materials. The findings provide a tool to narrow the search for material and device designs for injection lasing.

Solid cyclooctatetraene-based triplet quencher demonstrating excellent suppression of singlet-triplet annihilation in optical and electrical excitation.

Triplet excitons have been identified as the major obstacle to the realisation of organic laser diodes, as accumulation of triplet excitons leads to significant losses under continuous wave (CW) operation and/or electrical excitation. Here, we report the design and synthesis of a solid-state organic triplet quencher, as well as in-depth studies of its dispersion into a solution processable bis-stilbene-based laser dye. By blending the laser dye with 20 wt% of the quencher, negligible effects on the ASE thresholds, but a complete suppression of singlet-triplet annihilation (STA) and a 20-fold increase in excited-state photostability of the laser dye under CW excitation, were achieved. We used small-area OLEDs (0.2 mm2) to demonstrate efficient STA suppression by the quencher in the nanosecond range, supported by simulations to provide insights into the observed STA quenching under electrical excitation. The results demonstrate excellent triplet quenching ability under both optical and electrical excitations in the nanosecond range, coupled with excellent solution processability.

Laceioside, a new cycloartane saponin from Astragalus tephrosioides Boiss. var. lacei (Ali) Kirchoff.

Phytochemical investigation of the aerial parts of Astragalus tephrosioides Boiss. var. lacei (Ali) Kirchoff. (Family Fabaceae) resulted in the isolation of a new cycloartane glycoside laceioside (1). The structure of the previously undescribed compound 1 was established as 16ß-acetyloxy-3- O-ß-d-glucopyranosyloxy-cycloartan-11α,24ξ, 25-triol. The structure elucidation of compound 1 was based primarily on 1D and 2D-NMR techniques including 1H and 13CNMR spectra, DEPT and by 2D COSY, HSQC and HMBC experiments.

Mobility Evaluation of [1]Benzothieno[3,2- b][1]benzothiophene Derivatives: Limitation and Impact on Charge Transport.

Among contemporary semiconductors, many of the best performing materials are based on [1]benzothieno[3,2- b][1]benzothiophene (BTBT). Alkylated derivatives of these small molecules not only provide high hole mobilities but also can be easily processed by thermal vacuum or solution deposition methods. Over the last decade, numerous publications have investigated molecular structures and charge transport properties to elucidate what makes these molecules so special. However, the race toward ever higher mobilities resulted in significantly deviating values, which exacerbates linking molecular structure to electronic properties. Moreover, a recently arisen debate on overestimation of organic field-effect transistor mobilities calls for a revaluation of these numbers. We synthesized and characterized four BTBT derivatives with either one or two alkyl chains (themselves consisting of either 8 or 10 carbon atoms) and investigated their spectroscopic, structural, and electrical properties. By employing two-probe, gated four-point probe and gated van der Pauw measurements, we compare field-effect mobility values at room and low temperatures and discuss their feasibility and viability. We attribute mobility changes to different angles between molecule planes and core-to-core double-layer stacking of asymmetric BTBT derivatives and show higher mobilities in the presence of more and longer alkyl chains. A so-called "zipper effect" brings BTBT cores in closer proximity promoting stronger intermolecular orbital coupling and hence higher charge transport.

The isolation, purification and biological activity of a novel antibacterial compound produced by Pseudomonas stutzeri.

A novel compound designated zafrin [4beta-methyl-5, 6, 7, 8 tetrahydro-1 (4beta-H)-phenanthrenone] was isolated from a crude extract of a marine bacterium identified as Pseudomonas stutzeri. Zafrin showed strong antibacterial activity against both Gram-positive and Gram-negative bacteria. The compound was purified and its structure was elucidated by spectroscopic methods including 1H-nuclear magnetic resonance (NMR), 13C-NMR, 1D-NMR and 2D-NMR spectroscopy. It could be demonstrated that a purified solution of zafrin was active against several human pathogens, including Staphylococcus aureus, and Salmonella typhi. By contrast, zafrin did not inhibit the growth of eukaryotic organisms Candida albicans and Schizosaccharomyces pombe. The minimal inhibitory concentration for Gram-positive bacteria ranged from 50 to 75 microg mL(-1) and varied between 75 and 125 microg mL(-1) for Gram-negative bacteria. Zafrin lysed Bacillus subtilis cells grown in an osmotically protected medium, suggesting that it does not act upon the cell wall. Further investigation using B. subtilis indicated that the compound is bactericidal and is likely to target the cell membrane.

Diversolides A-G, guaianolides from the roots of Ferula diversivittata.

Seven sesquiterpene lactone derivatives, diversolides A-G (1-7), together with two known compounds, diversin (8) and stigmasterol, were isolated from the roots of Ferula diversivittata. The structures of these compounds were elucidated by extensive spectroscopic methods including 1D-(1H and 13C) and 2D-NMR experiments (DQF-COSY, HSQC, HMBC, and NOESY) as well as high-resolution EIMS. Compounds 1, 4 and 6-8 were tested for their in vitro antifungal and antibacterial activities. Some of the tested compounds showed moderate antifungal and antibacterial activities with minimum inhibitory concentration (MIC) values from 40 to 80microg/ml.

New terpenoids from Stachys parviflora Benth.

Two new triterpenoidal saponins were isolated from the n-butanolic extract of Stachys parviflora (Lamiaceae). Their structures were elucidated on the basis of spectral data as stachyssaponin A; 3beta, 15alpha, 19alpha, 21beta, 22alpha-pentahydroxyolean-12-ene-28-oic acid 3-O-{alpha-L-rhamnopyranosyl-(1 --> 3)-beta-D-glucopyranoside}-22-O-{alpha-L-arabinofuranosyl-(1 --> 3)-beta-D-glucopyranoside} (1) and stachyssaponin B; 2beta, 3beta, 15alpha, 21beta-tetrahydroxyolean-12-ene-28-oic acid 2-O-[alpha-L-arabinofuranoside]-3, 21-bis-O-[beta-D-glucopyranoside] (2).

Isolation, purification, structural elucidation and antimicrobial activities of kocumarin, a novel antibiotic isolated from actinobacterium Kocuria marina CMG S2 associated with the brown seaweed Pelvetia canaliculata.

AIMS: Screening of seaweed-associated bacteria capable of producing antimicrobials. METHODS AND RESULTS: Fifteen microbial strains, associated to the brown seaweed Pelvetia canaliculata (Linnaeus) attached to the rocks of Sonmiani Beach (Karachi, Pakistan), were screened. Crude extract filtrates of CMG S2 strain grew on Zobell marine agar (ZMA) had the most remarkable antimicrobial activity. Based on its phenotypic aspects (e.g. Gram-positive, microccoid form), biochemical characteristics (e.g. halotolerance) and genetic analyses, CMG S2 is identified as a putatively new Kocuria marina type strain belonging to the actinobacteria's class and micrococcaceae family. Thereby, the nucleotide sequence analysis of its full-length 16S ribosomal ribonucleic acid (rRNA) gene (GenBank accession number EU073966.1) displayed highest identity (i.e. 99%) and score (2630) with K. marina KMM 3905. Phylogenic trees analysis using the neighbor-joining method showed closest evolutionary distance of CMG S2 with KMM 3905 strain and K. carniphila (DC2201) specie. Interestingly, a unique ultraviolet (UV)-bioactive compound was purified from CMG S2 crude extracts by flash silica gel column and thin-layer chromatography (TLC) techniques. Its chemical structure was unraveled as 4-[(Z)-2 phenyl ethenyl] benzoic acid (PEBA, later named kocumarin) by nuclear magnetic resonance (NMR) spectroscopy techniques. Importantly, kocumarin demonstrated prominent and rapid growth inhibition against all tested fungi and pathogenic bacteria including methicillin-resistant Staphylococcus aureus (MRSA), with a minimal fungal inhibitory concentration (MFC) of 15-25µg/mL and a minimal (bacterial) inhibitory concentration (MIC) of 10-15µg/mL. SIGNIFICANCE AND IMPACT OF THE STUDY: Kocumarin represents a new promising natural antibiotic for in vivo and environmental applications.

Chemical composition, antioxidant and antimicrobial potential of essential oils from different parts of Daphne mucronata Royle.

This research work was executed to determine chemical composition, anti-oxidant and anti-microbial potential of the essential oils extracted from the leaves and stem of Daphne mucronata Royle. From leaves and stem oils fifty-one different constituents were identified through GC/MS examination. The antioxidant potential evaluated through DPPH free radical scavenging activity and %-inhibition of peroxidation in linoleic acid system. The stem's essential oil showed the good antioxidant activity as compared to leaves essential oil. Results of Antimicrobial activity revealed that both stem and leaves oils showed strong activity against Candida albicans with large inhibition zone (22.2 ± 0.01, 18.9 ± 0.20 mm) and lowest MIC values (0.98 ± 0.005, 2.44 ± 0.002 mg/mL) respectively. Leaves essential was also active against Escherichia coli with inhibition zone of 8.88 ± 0.01 mm and MIC values of 11.2 ± 0.40 mg/mL. These results suggested that the plant's essential oils would be a potential cradle for the natural product based antimicrobial as well as antioxidant agents.

Palladium(0) catalyzed Suzuki cross-coupling reaction of 2,5-dibromo-3-methylthiophene: selectivity, characterization, DFT studies and their biological evaluations.

Thiophene derivatives have shown versatile pharmacological activities. The Suzuki reaction proved a convenient method for C-C bond formations in organic molecules. In the present research work novel derivatives of 2,5-dibromo-3-methylthiophene (3a-k and 3l-p) has been synthesized, via Suzuki coupling reaction in low to moderate yields. A wide range of functional groups were well tolerated in reaction. Density functional theory investigations on all synthesized derivatives (3a-3p) were performed in order to explore the structural properties. The pharmaceutical potential of synthesized compounds was investigated through various bioassays (antioxidant, antibacterial, antiurease activities). The compounds 3l, 3g, 3j, showed excellent antioxidant activity (86.0, 82.0, 81.3%), respectively by scavenging DPPH. Synthesized compounds showed promising antibacterial activity against tested strains. 3b, 3k, 3a, 3d and 3j showed potential antiurease activity with 67.7, 64.2, 58.8, 54.7 and 52.1% inhibition at 50 µg/ml. Results indicated that synthesized molecules could be a potential source of pharmaceutical agents.

The analgesic, anti-inflammatory and calcium antagonist potential of Tanacetum artemisioides.

Several species of the genus Tanacetum are traditionally used in a variety of health conditions including pain, inflammation, respiratory and gastrointestinal disorders. In the current investigation, we evaluated the plant extract of T. artemisioides and some of its pure compounds (flavonoids) for analgesic, anti-inflammatory and calcium antagonist effects in various in-vivo and in vitro studies. Using the actetic acid induced writhing test, intraperitoneal (i.p) administration of the plant extract (25-50 mg/kg) and its flavonoid compounds TA-1 and TA-2 (1-5 mg/kg ) exhibited significant analgesic actvity. The maximum analgesic effect observed with the crude extract of the plant was 71% at 50 mg/kg, while that of compounds TA-1 and TA-2 (5 mg/kg i.p) was 75 and 47%, respectively. The plant extract and its pure compounds caused inhbition of formalin induced paw licking in mice predominatly in the second phase of the test. Diclofenac sodium, a standard reference compound, showed a simlar effect in these chemical induced pain models. In the carrgeenan induced rat paw edema assay, the plant extract (50-200 mg/kg i.p) demonstrated significant (P< 0.01) anti-inflammatory activity which was comparable to that obtained with diclofenac sodium and indomethacin. In isolated rabbit jejunum preprations the plant extract showed an atropine sensitive dose-dependent (0.10-1.0 mg/mL) spasmogenic activity followed by a spasmolytic effect at the next higher doses (3-5 mg/mL). The crude extract of the plant also inhibited the high K+-induced contractions, indicating a calcium channel blocking (CCB) activity, which was further confirmed when the plant extract caused a rightward shift in the Ca++ concentration response curves in the isolated rabbit jejunum preparations, similar to that seen with verapamil. The flavonoid compounds isolated from the plant were devoid of any activity in the isolated tissue preparations. These results indicate that the plant extract of T. artemisioides possesses analgesic, anti-inflammatory and CCB activities. The flavonoid compounds of the plant may have a role in its observed analgesic and antiinflammatory activities, while the CCB activity of the plant may be attributed to some other chemical constituents present. Moreover the findings support the traditional reputation of the genus Tanacetum for its therapeutic benefits in pain and inflammatory conditions.

Kinetics studies on triacontanyl palmitate: a urease inhibitor.

The mechanism of inhibition of jack bean and Bacillus pasteurii ureases was investigated by triacontanyl palmitate (1) which is a long-chain fatty ester and has been isolated from Symplocos racemosa Roxb. Lineweaver-Burk, Dixon plots, and their secondary replots showed that 1 is a non-competitive inhibitor of these enzymes. K(i) values were found to be 60.03 +/- 1.72 and 88.23 +/- 0.31 microM against jack bean and B. pasteurii ureases, respectively.

A new 14-membered cyclopeptide alkaloid from Zizyphus oxyphylla.

One new 14-membered frangulanine-type cyclopeptide alkaloid, oxyphyl line-A (1) has been isolated from the stem bark of Zizyphus oxyphylla together with the known 13-membered cyclopeptide, nummularine R (2). The structure was established on the basis of spectral studies particularly 2D NMR.