Guaianolide sesquiterpenes from Pulicaria crispa (Forssk.) Oliv

Phytochemical study, antioxidant and tyrosinase inhibitory activities of Pentzia monodiana Maire

Chemical investigation of the aerial parts of Pentzia monodiana Maire led to the isolation and identification of one sesquiterpene lactone glucoside of the guaianolide type (dihydropseudoivalin-4-O-β-d-glucopyranoside), along with nine known compounds including one diterpenoid, two sesquiterpenoids, three lignanes and three flavonoids. Their structures were established on the basis of spectroscopic analysis. All these compounds were evaluated for their DPPH radical scavenging and tyrosinase inhibitory activities. Only lignanes and flavonoids showed good to moderate DPPH radical scavenging activity with EC50 ranging from 10.6 to 47.5 μM. The new sesquiterpene lactone glucoside showed low tyrosinase inhibitory activity whereas the isolated lignanes and flavonoids exhibited a moderate activity with IC50 ranging from 45.4 to 97.2 μM).

The chemical composition of the aerial parts essential oil of Pulicaria odora (L.) Rchb. growing in Sicily (Italy)

The genus Pulicaria Gaertn. (Asteraceae) comprises more than ninety-two species as annual or perennial herbs or small shrubs, distributed in Africa, Europe, and Asia, and concentrated mainly in the Mediterranean region. Several species have been used in the traditional medicine of many countries. In the present study the chemical composition of the essential oil from aerial parts of Pulicaria odora (L.) Rchb., present in the Mediterranean region and collected in Sicily, was analysed by GC-MS. No papers have been previously published on the essential oil of the aerial part of this species. The result showed the presence of large quantity of carbonyl compounds (25.29%), oxygenated sesquiterpenes (23.28%) and thymol derivatives (16.76%). Chemical considerations with respect of other oils of Pulicaria taxa were carried out.

Unveiling the Phytochemical Profile and Biological Potential of Five Artemisia Species

The Artemisia L. genus comprises over 500 species with important medicinal and economic attributes. Our study aimed at providing a comprehensive metabolite profiling and bioactivity assessment of five Artemisia species collected from northeastern Romania (A. absinthium L., A. annua L., A. austriaca Jacq., A. pontica L. and A. vulgaris L.). Liquid chromatography–tandem high-resolution mass spectrometry (LC-HRMS/MS) analysis of methanol and chloroform extracts obtained from the roots and aerial parts of the plants led to the identification of 15 phenolic acids (mostly hydroxycinnamic acid derivatives), 26 flavonoids (poly-hydroxylated/poly-methoxylated flavone derivatives, present only in the aerial parts), 14 sesquiterpene lactones, 3 coumarins, 1 lignan and 7 fatty acids. Clustered image map (CIM) analysis of the phytochemical profiles revealed that A. annua was similar to A. absinthium and that A. pontica was similar to A. austriaca, whereas A. vulgaris represented a cluster of its own. Correlated with their total phenolic contents, the methanol extracts from both parts of the plants showed the highest antioxidant effects, as assessed by the DPPH and ABTS radical scavenging, CUPRAC, FRAP and total antioxidant capacity methods. Artemisia extracts proved to be promising sources of enzyme inhibitory agents, with the methanol aerial part extracts being the most active samples against acetylcholinesterase and glucosidase. All Artemisia samples displayed good antibacterial effects against Mycobacterium tuberculosis H37Ra, with MIC values of 64–256 mg/L. In conclusion, the investigated Artemisia species proved to be rich sources of bioactives endowed with antioxidant, enzyme inhibitory and anti-mycobacterial properties.

Plant Growth-Promoting Endophytic Bacterial Community Inhabiting the Leaves of Pulicaria incisa (Lam.) DC Inherent to Arid Regions

In this study, 15 bacterial endophytes linked with the leaves of the native medicinal plant Pulicaria incisa were isolated and identified as Agrobacterium fabrum, Acinetobacter radioresistant, Brevibacillus brevis, Bacillus cereus, Bacillus subtilis, Paenibacillus barengoltzii, and Burkholderia cepacia. These isolates exhibited variant tolerances to salt stress and showed high efficacy in indole-3-acetic acid (IAA) production in the absence/presence of tryptophan. The maximum productivity of IAA was recorded for B. cereus BI-8 and B. subtilis BI-10 with values of 117 ± 6 and 108 ± 4.6 μg mL-1, respectively, in the presence of 5 mg mL-1 tryptophan after 10 days. These two isolates had a high potential in phosphate solubilization and ammonia production, and they showed enzymatic activities for amylase, protease, xylanase, cellulase, chitinase, and catalase. In vitro antagonistic investigation showed their high efficacy against the three phytopathogens Fusarium oxysporum, Alternaria alternata, and Pythium ultimum, with inhibition percentages ranging from 20% ± 0.2% to 52.6% ± 0.2% (p ≤ 0.05). Therefore, these two endophytic bacteria were used as bio-inoculants for maize seeds, and the results showed that bacterial inoculations significantly increased the root length as well as the fresh and dry weights of the roots compared to the control plants. The Zea mays plant inoculated with the two endophytic strains BI-8 and BI-10 significantly improved (p ≤ 0.05) the growth performance as well as the nutrient uptake compared with an un-inoculated plant.

Metabolite profiles of Pulicaria crispa and P. incisa in relation to their in-vitro/ in-vivo antioxidant activity and hepatoprotective effect: A comparative mass spectrometry-based metabolomics

Plants of the genus Pulicaria (family: Asteraceae) are widely used in central Asia and the Middle East for treatment of different human diseases. Ultra performance liquid chromatography coupled to high resolution mass spectrometry (UPLC/MS) was utilized to establish the metabolic profiles of two Pulicaria species: P. crispa and P. incisa. 122 metabolites were identified including flavonoids (37), phenolic acids (22), sesquiterpenes (17), diterpenes (7), and fatty acids (27), with enrichment in methoxylated flavonoids (20), caffeoylquinic acid conjugates (14) xanthane sesquiterpenes (9) and hydroxylated fatty acids (20) in both Pulicaria species. The metabolite profile of P. incisa was characterized by the presence of tri- and tetra-methoxylated flavonoids while xanthane sesquiterpenes were the main chemical markers of P. crispa. Additionally, a novel sesquiterpene acid (dihydropulicaric acid) was annotated in both species based on its MS fragments. Antioxidant activity for P. crispa and P. incisa methanol extracts was assessed in vitro based on DPPH and ABTS assays and further in vivo using chlorpromazine intoxicated rat model. Results revealed that P. incisa extract was more effective in inhibiting both DPPH and ABTS free radicals (IC₅₀ 0.36 and 0.52 mg/mL, respectively) than P. crispa (IC₅₀ 0.51 and 0.73 mg/mL). In the animal model, antioxidant activity of P. incisa (20 mg/kg/day) was also slightly higher causing a 55 % reduction in MDA levels and 65 % increase in GSH activity compared to untreated animals. Furthermore, both extracts showed a hepatoprotective effect as revealed by improvement in levels of serum biomarkers of liver functions: total bilirubin, alanine transaminase (ALT) and aspartate transaminase (AST) comparable to silymarin at 25 mg/kg/day. These findings were also supported by the preserved integrity of the hepatic tissues of animals receiving either extracts at a dose of 20 mg/kg b.wt. The present study reveals for the potential antioxidant and hepatoprotective effects for Pulicaria in relation to its bioactive metabolites.

Suppression of LPS-Induced Hepato- and Cardiotoxic Effects by Pulicaria petiolaris via NF-κB Dependent Mechanism

Recently, there is an increasing interest in searching for harmless natural products isolated from plant materials that can be used as beneficial dietary supplements and/or therapeutic drug candidates. The present study aimed to test the potential protective role of Pulicaria petiolaris (PP, Asteraceae) against hepatic and cardiotoxic effects associated with lipopolysaccharide (LPS) injection. PP was given orally for 5 days at two different doses before LPS injection. Results have shown that LPS induced remarkable hepatic and cardiac injurious effects in mice. Hepatic damage was evident through increased serum transaminases, lactate dehydrogenase (LDH), alkaline phosphatase (ALP), and activity. Estimation of high levels of serum creatine kinase-MB (CK-MB) and cardiac troponin I indicated cardiac damage. Histopathological examination of liver and heart confirmed the biochemical results. Increase in oxidative stress along with a depressed antioxidant status of liver and heart were observed in LPS-intoxicated animals. Furthermore, LPS induced activation of nuclear factor-κB (NF-κB) and subsequent elevation of inflammatory cytokines (TNF-α, IL-6). On the other hand, PP treatment successfully safeguards both organs against LPS-induced injury as indicated by the improvement of the biochemical and histopathological parameters. These results suggest that PP ameliorates LPS-induced hepatic and cardiac oxidative injurious effects via antioxidant and anti-inflammatory effects.

Sesquiterpenes-Rich Essential Oil from Above Ground Parts of Pulicaria somalensis Exhibited Antioxidant Activity and Allelopathic Effect on Weeds

Pulicaria genus (fleabane) is characterized by its fragrant odor due to the presence of essential oil (EO). According to the literature reviews, the EO of Pulicaria somalensis O.Hoffm. (Shie) is still unexplored. For the first time, 71 compounds were characterized in EO derived from above-ground parts of P. somalensis collected from Saudi Arabia. Sesquiterpenes represented the main components (91.8%), along with minor amounts of mono-, diterpenes, and hydrocarbons. Juniper camphor (24.7%), α-sinensal (7.7%), 6-epi-shyobunol (6.6%), α-zingiberene (5.8%), α-bisabolol (5.3%), and T-muurolol (4.7%) were characterized as main constituents. The correlation analysis between different Pulicaria species showed that P. somalensis has a specific chemical pattern of the EO, thereby no correlation was observed with other reported Pulicaria species. The EO showed significant allelopathic activity against the weeds of Dactyloctenium aegyptium (L.) Willd. (crowfoot grass) and Bidens pilosa L. (hairy beggarticks). The IC50 value on the germination of D. aegyptium was double that of B. pilosa. The IC50 values on the root growth of B. pilosa and D. aegyptium were 0.6 mg mL−1 each, while the shoot growths were 1.0 and 0.7 mg mL−1, respectively. This variation in the activity could be attributed to the genetic characteristics of the weeds. Moreover, the EO exhibited significant antioxidant effects compared to ascorbic acid. Further studies are necessary to verify if these biological activities of the EO could be attributable to its major compounds.

Anticancer Potential of Pulicaria crispa Extract on Human Breast Cancer MDA-MB-231 Cells

Background:

Breast cancer is the common cause of deaths among women globally with 15% mortality globally.

Introduction:

Today, about 80% of the rural population depends on natural products as primary health care. Pulicaria crispa (L., family Compositae) is utilized in traditional medicine for curing colds, coughs, colic, and excessive sweating and as a carminative.

Methods:

The extracts of Pulicaria crispa; grown in Saudi Arabia; were assessed to measure the cytotoxicity with MDA-MB-231 breast cancer cell lines. Soxhlet extraction was utilized for stem, leaves and flower with 70% ethanol. The cytotoxicity of the extracts with MDA-MB-231 breast cancer cells was evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays.

Results:

The apoptotic cellular morphological alterations were detected by fluorescence microscopes. The results indicated that Pulicaria crispa exhibited a strong anticancer activity with a halfmaximal inhibitory concentration (IC50) of 180 µg/mL against breast cancer cells. The loss in cell integrity, shrinkage of cytoplasm, and cell detachment were seen in the extract treated with MDAMB- 231 cells. The cell death was due to membrane destruction.

Conclusion:

Pulicaria crispa extracts indicated significant cytotoxicity against human breast cancer cells (MDA-MB-231 cells). The extract of this plant may be given to the patients having breast cancer.

Further Guaianolides from Chrysophthalmum montanum

Five new guaiane type sesquiterpene lactones; 6β-hydroxy-guai-9(10)-en-12,8β-olide-4β- O- 1 -glucopyranoside (1), 6 β-acetoxy-guai-9(10)-en-12,8 1 -olide-4 β- O-β-glucopyranoside (2), 5α,10β-dihydroxy-guai-1(2)-en-12,8β-olide (3), 4β-hydroxy-guai-(2)-en-12,8β-olide-10- O-β-glucopyranoside (4a), 1α,4α,10α-trihydroxy-guaian-12,8β-olide (5) were identified in the repeated examination of the aerial parts of the Chrysophthalmum montanum (DC) Boiss. lie structures of the isolated compounds were elucidated by extensive 1D- and 2D-NMR spectroscopic analyses in combination with HRESIMS experiments.

Allergenic sesquiterpene lactones from cushion bush (Leucophyta brownii Cass.): new and old sensitizers in a shrub-turned-a-pot plant

BACKGROUND

The Australian cushion bush (Leucophyta brownii) of the Compositae family of plants has become a popular pot and container plant. The plant produces the sesquiterpene lactone allergen calocephalin.

OBJECTIVES

To assess the sensitizing potential of sesquiterpene lactones from cushion bush.

PATIENTS/MATERIALS/METHODS

Eleven Compositae-sensitive patients were patch tested with seven sesquiterpene lactones isolated from cushion bush.

RESULTS

Six of seven sesquiterpene lactones elicited positive reactions in 4 of 11 patients.

CONCLUSIONS

The well-known sesquiterpene lactone pseudoivalin and its derivative pseudoivalin acetate, as well as calocephalin and tomentosin, were confirmed to be sensitizers, whereas leucophytalin A and 4α-hydroxy-5αH,10αH-1,11(13)-guaidien-8β,12-olide were shown to be allergenic for the first time. The patch test reaction patterns seem to follow the chemical patterns, which may eventually make it possible to trace primary sensitizers and advise patients more precisely.

Phenolic constituents of Pulicaria undulata (L.) C.A. Mey. sub sp. undulata (Asteraceae): Antioxidant protective effects and chemosystematic significances

One new naturally isoflavone compound, 5,7,2′,3′,4′ penta hydroxyl isoflavone-4′-O-β-glucopyranoside (1) was isolated from the aqueous methanol extract (AME) of Pulicaria undulata subsp. undulata, together with seven known compounds: kaempferol (2), kaempferol 3-O-β-glucoside (3), quercetin (4), quercetin 3-O-β-glucoside (5), quercetin 3-O-β-galactoside (6), quercetin 3,7-di OCH₃ (7), and caffeic acid (8). Their structures were established through chemical (acid hydrolysis) and spectral analysis (UV, NMR, and ESIM). The AME and some isolated compounds were evaluated as protective agents. Free radical scavenging using a microscaled 2,2-diphenyl-1-picrylhydrazyl assay was used to assess the direct antioxidant properties that were evaluated by the ability to protect murine Hepa1c1c7 liver cells against damage induced by the organic peroxide tert-butyl hydroperoxide. The neutral red uptake assay (NRU) was used to record the activity. Results of the 2,2-diphenyl-1-picrylhydrazyl assay recorded differential scavenging properties in ascending order: 5,7,2′,3′,4′ penta hydroxyl isoflavone-4′-O-β-glucopyranoside > quercetin > quercetin 3-O-galactoside > caffeic acid > quercetin 3,7-di-OCH₃ > kaempferol with 50% inhibitory concentrations of 3.9 μM, 7.5 μM, 11.4 μM, 12.2 μM, 78.1 μM, and 252.3 μM, respectively. The antioxidative potential reveals the potency of AME, quercetin, and quercetin 3,7-di-OCH₃. The latter compound showed full protection at 100 μM (33 μg/mL) against the induced toxicant effect where the 50% effective concentration was calculated as 33.6 ± 1.7 μM (11.1 μg/mL). In addition to quercetin, which was extensively shown previously as a cytoprotective agent, AME was less potent; it was capable of protecting 75% at 100 μg/mL with 50% effective concentration of 92.3 ± 4 μg/mL. Moreover, the isolated flavonoids were found to be significantly chemosystematic markers.

Nematicidal and antimicrobial activities of methanol extracts of 17 plants, of importance in ethnopharmacology, obtained from the Arabian Peninsula

Aim/Background:

The development of resistance to synthetic drugs by target organisms is a major challenge facing medicine, yet locked within plants are phytochemicals used in herbal medicine (especially in the Arabian Peninsula) that may find application in this regard. In pursuit of unlocking these “hidden treasures,” the methanol extracts of leaves, aerial parts, fruits, and resins of 17 plants used in the Arabian Peninsula were screened for antimicrobial activities.

Materials and Methods:

The nematicidal, antibacterial, and antifungal activities were determined using appropriate assays. Steinernema feltiae, Staphylococcus carnosus, Escherichia coli, and Saccharomyces cerevisiae were used as test organisms. Concentrations of the extracts ranging from 0.5 to 20 mg/ml were tested and appropriate statistical tests performed on the data generated.

Results:

The results show that extracts from Solanum incanum, Chenopodium murale, Commiphora myrrha, Anthemis nobilis, and Achillea biebersteinii were the most active and had very high activities against two or more of the test organisms at low concentrations. Extracts of the leaves of S. incanum and resins of Ferula asafoetida were the most active nematicides, with significant activity at 0.5 mg/ml. Extracts of C. myrrha and C. murale had the most active antibacterial activity with inhibition zones of 12-15 mm and minimum inhibitory concentrations (MICs) of 2.5 mg/ml for both bacteria. Extracts of the leaves of A. biebersteinii were the most active fungicide, giving an MIC of 1.5 mg/ml.

Conclusion:

The results validate the use of these plants in ethnopharmacology, and open new vistas of opportunities for the development of cheap but effective agents that may be useful against infectious diseases.

A new monoterpene glucoside and complete assignments of dihydroflavonols of Pulicaria jaubertii: potential cytotoxic and blood pressure lowering activity

One new monoterpene glucoside and five dihydroflavonols were isolated for the first time from the aerial parts of Pulicaria jaubertii and identified as p-menthane-2-O-β-D-glucopyranoside [1], dihydroquercetin (taxifolin) [2], 7,3'-di-O-methyltaxifolin [3], 3'-O-methyltaxifolin [4], 7-O-methyltaxifolin (padmatin) [5] and 7-O-methyl-dihydrokampferol (7-O-methylaromadenderin) [6]. The structures of these compounds were unambiguously assigned on the basis of NMR spectroscopic data ((1)H, (13)C, DEPT, HSQC, HMBC) and MS analysis. 2D-NMR methods required revision of assignments of H-6 and H-8 for dihydroflavonol compounds. Possible cytotoxic activity as well as blood pressure (BP) lowering activity were tested. The alcoholic extract showed cytotoxic activity against prostate carcinoma (PC-3), breast carcinoma (MCF-7) and hepatocellular carcinoma (HepG-2) human cell lines with IC50 19.1, 20.0 and 24.1 μg, respectively. The higher dose levels of the alcoholic extract significantly reduced normal BP of rats in a dose-dependent manner.

New sesquiterpenoids from Ambrosia artemisiifolia L

A new pseudoguaianolide 1 and two new guaiane-type sesquiterpene glucosides 2 and 3, were isolated from the aerial parts of Ambrosia artemisiifolia L together with two known sesquiterpene dilactones 4 and 5. The new compounds were determined on the basis of spectroscopic and chemical methods to be 3β-acetoxy-4β-hydroxy-1α,7α, 10β,11αH-pseudoguaia-12,8β-olide (1), 1β,7β,9β,10β,13αH-guaia-4(5)-en-12,6β-olide 9-O-β-d-glucoside (2) and 4β-hydroxy-1α,5α,7α,9αH-guaia-10(14),11(13)-dien-12-acid 9-O-β-d-glucoside (3). The isolated compounds were evaluated for cytotoxicity against human promyelocytic leukemia HL-60 cell lines in vitro, but were all inactive.

Chaperone potential of Pulicaria undulata extract in preventing aggregation of stressed proteins

This study examined the effect of an aqueous extract of Pulicaria undulata on the 1,4-dithiothreitol (DTT)-induced aggregation of proteins. The effects of the chaperone properties of P. undulata extract on protein aggregation were determined by measuring light scattering absorption, fluorescence, and circular dichroism (CD) spectroscopy. The aqueous extract of P. undulata possesses good chaperone properties but the protection effect was varied in different protein. The extract showed a higher level of protection in high molecular weight proteins than in those of low molecular weight. Using a fluorescence study, the present study provides information on the hydrophobic area of proteins interacting with the P. undulata extract. In fact, by increasing the concentration of the P. undulata extract, the hydrophic area of the protein decreased. CD spectroscopy also revealed that DTT caused changes in both the tertiary and the secondary structure of the proteins, while in the presence of P. undulata extract, there was little change. Our finding suggests the possibility of using P. undulata extract for the inhibition of aggregation and the deposition of protein in disease.

Biogenic synthesis of palladium nanoparticles using Pulicaria glutinosa extract and their catalytic activity towards the Suzuki coupling reaction

Biosynthesized Pd NPs: wonderful catalyst towards the Suzuki coupling reaction under aerobic conditions.

Protective and antioxidant effects of a chalconoid from Pulicaria incisa on brain astrocytes

Oxidative stress is involved in the pathogenesis of neurodegenerative diseases such as Parkinson's and Alzheimer's diseases. Astrocytes, the most abundant glial cells in the brain, protect neurons from reactive oxygen species (ROS) and provide them with trophic support, such as glial-derived neurotrophic factor (GDNF). Thus, any damage to astrocytes will affect neuronal survival. In the present study, by activity-guided fractionation, we have purified from the desert plant Pulicaria incisa two protective compounds and determined their structures by spectroscopic methods. The compounds were found to be new chalcones—pulichalconoid B and pulichalconoid C. This is the first study to characterize the antioxidant and protective effects of these compounds in any biological system. Using primary cultures of astrocytes, we have found that pulichalconoid B attenuated the accumulation of ROS following treatment of these cells with hydrogen peroxide by 89% and prevented 89% of the H₂O₂-induced death of astrocytes. Pulichalconoid B exhibited an antioxidant effect both in vitro and in the cellular antioxidant assay in astrocytes and microglial cells. Pulichalconoid B also caused a fourfold increase in GDNF transcription in these cells. Thus, this chalcone deserves further studies in order to evaluate if beneficial therapeutic effect exists.

Anticancer attributes of desert plants: a review

The ever-increasing emergence of the resistance of mammalian tumor cells to chemotherapy and its severe side effects reduces the clinical efficacy of a large variety of anticancer agents that are currently in use. Thus, despite the significant progress in cancer therapeutics in the last decades, the need to discover and to develop new, alternative, or synergistic anticancer agents remains. Cancer prevention or chemotherapy based on bioactive fractions or pure components derived from desert plants with known cancer-inhibiting properties suggests promising alternatives to current cancer therapy. Plants growing on low nutrient soils and/or under harsh climatic conditions, such as extreme temperatures, intense solar radiation, and water scarcity, are particularly susceptible to attack from reactive oxygen species and have evolved efficient antioxidation defense systems. The many examples of desert plants displaying anticancer effects as presented here indicates that the same defensive secondary metabolites protecting them against the harsh environment may also play a protective or a curative role against cancer, as they also do against diabetes, neurodegenerative, and other acute and chronic diseases. The present review highlights a plethora of studies focused on the antineoplastic properties of desert plants and their prinicipal phytochemicals, such as saponins, flavonoids, tannins, and terpenes. Although many desert plants have been investigated for their antitumor properties, there are many that still remain to be explored - a challenge for the prospective cancer therapy of the future.

Green synthesis of silver nanoparticles mediated by Pulicaria glutinosa extract

The green synthesis of metallic nanoparticles (NPs) has attracted tremendous attention in recent years because these protocols are low cost and more environmentally friendly than standard methods of synthesis. In this article, we report a simple and eco-friendly method for the synthesis of silver NPs using an aqueous solution of Pulicaria glutinosa plant extract as a bioreductant. The as-prepared silver NPs were characterized using ultraviolet-visible spectroscopy, powder X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy. Moreover, the effects of the concentration of the reductant (plant extract) and precursor solution (silver nitrate), the temperature on the morphology, and the kinetics of reaction were investigated. The results indicate that the size of the silver NPs varied as the plant extract concentration increased. The as-synthesized silver NPs were phase pure and well crystalline with a face-centered cubic structure. Further, Fourier-transform infrared spectroscopy analysis confirmed that the plant extract not only acted as a bioreductant but also functionalized the NPs' surfaces to act as a capping ligand to stabilize them in the solvent. The developed eco-friendly method for the synthesis of NPs could prove a better substitute for the physical and chemical methods currently used to prepare metallic NPs commonly used in cosmetics, foods, and medicines.

Generic and functional diversity in endophytic actinomycetes from wild Compositae plant species at South Sinai - Egypt

The diversity of culturable endophytic actinomycetes associated with wild Compositae plants is scantily explored. In this study, one hundred and thirty one endophytic actinobacteria were isolated from ten Compositae plant species collected from South Sinai in Egypt. Microscopic and chemotaxonomic investigation of the isolates indicated fourteen genera. Rare genera, such as Microtetraspora, and Intrasporangium, which have never been previously reported to be endophytic, were identified. Each plant species accommodated between three to eight genera of actinobacteria and unidentified strains were recovered from seven plant species. The generic diversity analysis of endophytic assemblages grouped the plant species into three main clusters, representing high, moderate and low endophytic diversity. The endophytes showed high functional diversity, based on forty four catabolic and plant growth promotion traits; providing some evidence that such traits could represent key criteria for successful residence of endophytes in the endosphere. Stress-tolerance traits were more predictive measure of functional diversity differences between the endophyte assemblages (Shannon's index, p = 0.01). The results indicate a potential prominent role of endophytes for their hosts and emphasize the potency of plant endosphere as a habitat for actinobacteria with promising future applications.

Antioxidant and astroprotective effects of a Pulicaria incisa infusion

Oxidative stress is involved in the pathogenesis of neurodegenerative diseases such as Parkinson's and Alzheimer's diseases. Astrocytes, the most abundant glial cells in the brain, protect neurons from reactive oxygen species (ROS) and provide them with trophic support, such as glial-derived neurotrophic factor (GDNF). Thus, any damage to astrocytes will affect neuronal survival. In the present study, an infusion prepared from the desert plant Pulicaria incisa (Pi) was tested for its protective and antioxidant effects on astrocytes subjected to oxidative stress. The Pi infusion attenuated the intracellular accumulation of ROS following treatment with hydrogen peroxide and zinc and prevented the H(2)O(2)-induced death of astrocytes. The Pi infusion also exhibited an antioxidant effect in vitro and induced GDNF transcription in astrocytes. It is proposed that this Pi infusion be further evaluated for use as a functional beverage for the prevention and/or treatment of brain injuries and neurodegenerative diseases in which oxidative stress plays a role.

The renaissance of alpha-methylene-gamma-butyrolactones: new synthetic approaches

The amount of research activity concerning alpha-methylene-gamma-butyrolactones and alpha-alkylidene-gamma-butyrolactones has increased dramatically in recent years. This Review summarizes the structural types, biological activities, and biosynthesis of these compounds, concentrating on publications from the past 10 years. Traditional approaches to alpha-methylene-gamma-butyrolactones and alpha-alkylidene-gamma-butyrolactones are then reviewed together with novel approaches, including those from our own research group, reported more recently.