Dicoumarol: from chemistry to antitumor benefits

Dicoumarol, a coumarin-like compound, is known for its anticoagulant properties associated with the ability to inhibit vitamin K, being prescribed as a drug for several decades. The pharmaceutical value of dicoumarol turned it into a focus of chemists' attention, aiming its synthesis and of dicoumarol derivatives, bringing to light new methodologies. In recent years, several other bioactive effects have been claimed for dicoumarol and its derivatives, including anti-inflammatory, antimicrobial, antifungal, and anticancer, although the mechanisms of action underlying them are mostly not disclosed and additional research is needed to unravel them. This review presents a state of the art on the chemistry of dicoumarols, and their potential anticancer characteristics, highlighting the mechanisms of action elucidated so far. In parallel, we draw attention to the lack of in vivo studies and clinical trials to assess the safety and efficacy as drugs for later application.

Paclitaxel: Application in Modern Oncology and Nanomedicine-Based Cancer Therapy

Paclitaxel is a broad-spectrum anticancer compound, which was derived mainly from a medicinal plant, in particular, from the bark of the yew tree Taxus brevifolia Nutt. It is a representative of a class of diterpene taxanes, which are nowadays used as the most common chemotherapeutic agent against many forms of cancer. It possesses scientifically proven anticancer activity against, e.g., ovarian, lung, and breast cancers. The application of this compound is difficult because of limited solubility, recrystalization upon dilution, and cosolvent-induced toxicity. In these cases, nanotechnology and nanoparticles provide certain advantages such as increased drug half-life, lowered toxicity, and specific and selective delivery over free drugs. Nanodrugs possess the capability to buildup in the tissue which might be linked to enhanced permeability and retention as well as enhanced antitumour influence possessing minimal toxicity in normal tissues. This article presents information about paclitaxel, its chemical structure, formulations, mechanism of action, and toxicity. Attention is drawn on nanotechnology, the usefulness of nanoparticles containing paclitaxel, its opportunities, and also future perspective. This review article is aimed at summarizing the current state of continuous pharmaceutical development and employment of nanotechnology in the enhancement of the pharmacokinetic and pharmacodynamic features of paclitaxel as a chemotherapeutic agent.

The "Sandwich" System: A Potential Solution for Protecting Overwintering Cornu aspersum Snails Reared in Semi-Intensive Heliciculture Farms in Colder Climates

Simple Summary

The Italian semi-intensive (ISISF) technology is widely used for rearing the Mediterranean snail, Cornu aspersum. It relies on protecting overwintering specimens with Lutrasil frost cloth (LFC). This approach yielded elevated mortalities in Romanian snail farms. We aimed to develop a simple and effective system for protecting overwintering C. aspersum adults in colder climates. This three-year, three-phase experiment investigated selected behavioral aspects and thermal protection efficiency of different protective structures. Mature gastropods in preparation for hibernation exhibited a significant preference for wood and ridge-tile micro shelters. Soil texture significantly influenced the burrowing behavior, but not the burrowing depth. The structure soil/LFC/straw/10-cm air cushion/high-density polyethylene (HDPE)—the “sandwich” system—was selected to be used as a protective system. Under farm conditions, adult snails tended to hibernate clustered together, attached to the lower surface of micro shelters. The “sandwich” system coupled with using ridge-tile/wood micro shelters resulted in significantly higher survival thanthe sole use of LFC. Predator occurrence appeared to exert a minor effect on snail survival. These data render the “sandwich” system a potential solution for overwintering C. aspersum breeders in colder climates.

Abstract

(1) Background: Hibernation in pens covered with LFC was associated with high mortality of C. aspersum snails in Romanian snail farms. This three-year study aimed to develop a simple, but effective system for protecting breeders in colder climates. (2) Methods: The first phase investigated the (pre)hibernal burrowing behavior and the overwintering habitat choice. Protective structures based on straw, LFC, and/or HDPE were tested at pilot level (no snails). The most suitable system was applied under farm conditions. (3) Results: Wood and ridge-tile micro shelters were significantly preferred to corrugated iron micro shelters. Burrowing specimens acted as shallow-burrowers, and this behaviorwas significantly more common for looser soils. All pilot systems displayed significantly higher thermal protection efficiency compared to the sole use of LFC. The balance between straw moistening and thermal protection favored using structure soil/LFC/straw/10-cm air cushion/HDPE. Its use yielded significantly higher survival compared to the sole use of LFC. Most hibernating snails clustered together in large groups, attached on the lower surface of micro shelters. Predator occurrence appeared to marginally affect overwintering survival. (4) Conclusions: The “sandwich” system could be an effective solution for overwintering mature C. aspersum snails in colder climates.

THE EFFECT OF SEED TREATMENT ON THE MAIN PATHOGENS PRESENT IN WHEAT AGROECOSYSTEMS

Wheat crop (Triticum aestivum L.) from Poaceae family is affected by many diseases that cause yield losses. The present paper addresses a topic of economic, agrotechnics and social importance of wheat crop (occupying the first place among the Romanian cultivated crop, feeding 35 to 40% of world population). The study had as main objective product testing like Yunta 246 FS (imidacloprid 233 g/l + tebuconazol 13 g/l), Team Micorriza Plus (Glomus intraradices 150 spore/g + Glomus mosseae 150 spore/g + organic matter 56% and Rhizosphere Bacteria 107 UFC/g) and Condor (Trichoderma spp. 1 x 109 spore/g + Glomus sp. 10 spore/g + Rhizosphere Bacteria 1 x 107 UFC/g and organic matter 7%) applied in the pathosystem wheat/pathogens. The research was conducted in the western part of Romania, in 2010-2012, experience was placed after Latin rectangle method with 10 variants (they are different by product and dose applied) and the data were statistically interpreted. Results showed the presence of pathogens Septoria tritici, Drechslera tritici repentis and Drechslera teres in experimental variants. Statistical analysis showed that the most effective chemical mixture was imidacloprid + tebuconazol at the highest dose tested (3 l/t). Regarding the non-chemical product testing, the product Condor gave positive results. The highest values of quality parameters (protein and gluten) were obtained in the variants treated with Yunta 246 FS.

Design of optimal solvent for extraction of bio-active ingredients from six varieties of Medicago sativa

Background

Extensive research has been performed worldwide and important evidences were collected to show the immense potential of plants used in various traditional therapeutic systems. The aim of this work is to investigate the different extracting solvents in terms of the influence of their polarity on the extracting ability of bioactive molecules (phenolic compounds) from the M. sativa flowers.

Results

The total phenolic content of samples was determined using the Folin Ciocalteu (FC) procedure and their antioxidant activity was assayed through in vitro radical decomposing activity using the radical DPPH° assay (IUPAC name for DPPH is (phenyl)–(2,4,6–trinitrophenyl) iminoazanium). The results showed that water was better than methanol and acetic acid for extracting bioactive compounds, in particular for total phenolic compounds from the flowers of alfalfa. The average content of bioactive molecules in methanol extract was 263.5±1.02 mg GAE/100g of dry weight lyophilized extract. The total phenolic content of the tested plant extracts was highly correlated with the radical decomposing activity. However, all extracts were free–radical inhibitors, but the water extract was more potent than the acetic and the methanol ones. The order of inhibitor effectiveness (expressed by IC₅₀) proved to be: water extract (0.924mg/mL) > acetic acid extract (0.154mg/mL) > methanol (0.079mg/mL). The profiles of each extract (fingerprint) were characterized by FT–MIR spectroscopy.

Conclusions

The present study compares the fingerprint of different extracts of the M. sativa flowers, collected from the wild flora of Romania. The total phenolic content of the tested plant extracts was highly correlated with the radical decomposing activity. The dependence of the extract composition on the solvent polarity (acetic acid vs. methanol vs. water) was revealed by UV–VIS spectrometry and Infrared fingerprint.

The effectivenes of Trichotim in control of Cydia pomonella L. in western Romania

In the last years a significant attack increasing of codling moth was observed in the western part of Romania. In order to reduce the population of this pests a bioproduct was used named Trichotim based on entomophagous insect Trichogramma sp. Trichotim is a Romanian product certified in year 2000 with the purpose to control the pests present in various cultures such us cabbage, vineyards and fruits plantations. The study was expanded over two years (2008 and 2009), in a super intensive apple orchard of Didactical Experimental Station part of University of Agricultural Sciences Timisoara. In order to control the codling moth, the product Trichotim was used three times correlated to pest biology (two releasing of Trichogramma wasps in the time of first generation and one release in the time of second generation of the pest), releasing 300.000 wasps/ha in total, where 250.000 wasps in first generation time of the codling moth respectively 50.000 wasps in the time of second generation of the pest. The releasing of entomophagous species Trichogramma succeeded at two days after maximal flight values of Cydia pomonella L. The flight curves was realized based on pheromonal traps ATRAPOM placed in tree canopy in stage BBCH 69 (end of flowering, all petals fallen). In order to assess the efficacy of Trichotim the observation was conducted 14 days before fruit harvesting. In the plots where 300.000 wasps were released, the fruits were attacked in percent of 12,33% (efficacy 87,67%) in year 2008 and respectively 14,66% (efficacy 85,33%) in 2009. In untreated plots (control) the fruits were attacked in percent of 23% in 2008 respectively 27,33% in 2009.

The influence of weather and geographical conditions on flight dynamics of WCR adults

Since the appearance of western corn rootworm (Diabrotica virgifera virgifera Le Conte) (Coleoptera: Chrysometidae) in Romania, many researchers have been made, in more or less success. In this study we try to clarify the ecology of the species in order to predict its evolution and its potential area of distribution. In Romania, this species was signalled for the first time in 1996, in western part of country neighbouring with Hungary. This region is an important area for maize production for seed and silage. Together, the climatic conditions, altitude and their influence on species behaviour and distribution have become more apparent. Their habitat and survival strategies are strongly dependent on local weather patents and altitude. In order to investigate the potential impact of weather and altitude on pest populations, a clear understanding of the nature and characterization of pest is required. In general, most pest species are influenced by warm, rainfall and altitude. Taking into consideration our data from the years 2008 and 2009, we can emphasize a very serious influence of air temperature, rainfall and altitude on WCR flight dynamics in adults. Dry and warm conditions generally lead to increasing of insects' number. Our data shown positive correlations between air temperature (daily mean) and adults number captured on pheromone traps (daily mean), but the there are limits from which these become negative. The same trend was recorded in previous research period (2004-2006). The rainfall is an important factor that influences adults' dynamics in maize fields. Excessive rainfall leads to adults' number decreasing. Our daily observations showed a decreasing number of beetles while rainfall increases. Regarding the altitude, we observed a decreasing number of WCR adults at once the attitude increase. For capture of adults we used pheromone traps, in 3 replications (T1, T2 and T3) at difference altitude where maize was grown. Significant relationship of WCR flight dynamic with weather and geographical conditions were found. Activities were carried out under the PN-II-ID-PCE-2007-1/RO project.

Weed control in conventional and transgenic maize with resistance to glyphosate

The researches were conducted in order to observe the behaviour of conventional and glyphosate resistant transgenic maize to different weed control methods. In this paper, the obtained results are presented. The study was conducted in experimental years 2008-2009 in the frame of Didactical Station USAMVB Timisoara. In order to conduct this study, 4 variants cultivated with conventional maize DKC 5143 and 8 variants cultivated with transgenic maize DKC-MON88017 with resistance against Diabrotica virgifera virgifera and to glyphosate. The efficacy of weed control methods was assessed, as well as the herbicide selectivity to cultivated maize hybrid. The weed coverage degree in control plot (V2) was 304 weeds/sqm in the first year and 465 weeds/sqm in the second year. In the variants cultivated with transgenic maize the control was up to 90% much more than control percent achieved in conventional variants. Although, in order to achieve an efficient control (higher than 95%), even to transgenic maize, two glyphosate sequential treatments has to be done. The yield results were positive correlated to the different control methods. However those were affected by climatic conditions recorded in experimental years.

Monitoring western corn rootworm (Diabrotica v. virgifera) adults: situation in Romania 2008

Romania is part of the southeast European expansion zone of the invasive rootworm species Diabrotica v. virgifera LeConte (Col.: Chrysomelidae) (WCR). The pest originated in North America and reached Belgrade airport with US foreign aid air shipments prior to 1992. Today, about 20 years after its introduction, WCR is a major maize pest which regionally causes economic damage to maize. However, it also can colonize secondary hosts which complicates IPM efforts. Basis for sound management is a reliable monitoring system. The easiest and cheapest way is to use Metcalf type monitoring traps for the mobile adults. Sex pheromones and plant kairomones for trapping are commercially available. Traps can be either bought or cheaply prepared. Metcalf traps with adhesive and lure cost about 15 cents per piece. So state-wide trapping is no longer a problem for less affluent countries. Results from two independent locations in 2008 report flight curves and attractively of secondary hosts like Sorghum spp. in relation to the principle host Zea mays. In addition, high capacity traps baited with pheromone are surprisingly effective, and, in combination with the chemically inert, absorptive silica powder AL 06, will be considered as future alternatives in cases where frequent monitoring is unfeasible and were a large holding capacity is indicated.

Natural enemies in control of invasive species Diabrotica virgifera Virgifera from maize crops

The invasive Diabrotico virgifera virgifera Le Conte (western corn rootworm) species has become a very important pest of maize growing areas from Europe. Incidence of this pest in Europe and Romania attract the specialist's attention and European organisms regarding substantial changes which save the yield. Current trends in control regard the using natural enemies' because non-pollutants effects. In this way it follows protection of useful scale from agroecosystems and their exploitation in control of invasive population. It were take the soil and surface samples for establish the presence of control biological agents. The maximum appearance period of invasive species (July, August) is very important in establishing the analogy with appearance of predator's species. From natural enemies of Diabrotica virgifera can be notice follow species: Speira diademata, Argiope bruennichi, Theridion impressum (Arachnida: Araneae), Coccinella sp., Pseudophomus rufipes (Insecta: Coleoptera). The spider species Argiope bruennichi (Araneae: Araneidae) and Theridion impressum (Araneae: Theriidae) are able to diminish significantly population of adults, especially in appearance of maize silk. The aim of the theme we approach is to find solutions to the issues created by invasive species Diabrotica virgifera virgifera using an ecological alternative of the chemical methods, as an-polluting biological methods. In a period when easily apply to chemical substances we consider that is absolutely necessary the introduction of these biological methods.

Biological control of late blight (Phytophthora infestans (Mont.) de Bary) in tomatoes with mycoextracts from Fusarium culmorum and Fusarium graminearum

Following a screening completed over several species of fungus for establishing the efficiency of the extracts produced from them, against agent causing the late blight--Phytophthora infestans--two species of fungus were selected--Fusarium graminearum and Fusarium culmorum--in order to employ them and their strains with different virulence in the pathosystem fungi/Lycopersicumm esculentum. The utilized extracts are based on ethanol and obtained from mycelium and culture filtrate. Extract was applied 2 and respectively 7 days before the artificial inoculation, realized on the detached tomato's leaves and maintained at 17 degrees C and air relative humidity of 100%. The evaluation was done 6 days after the inoculation. The results show that for the treatment applied 2 days before inoculation the intensity of the attack was reduced by aprox. 60% compared with the control but for the inoculation at 7 days after the treatment, the intensity was not diminished.

Control of Sorghum halepense (L.) species in western part of Romania

Sorghum holepense is an extremely wide spread species, being met in many European, Asian, American and African countries and covering approximately 1/3 of the land cultivated with fields crops, grapevine, fruit trees and vegetables. In Romania, Sorghum halepense is present in almost all the country, invading in hoed-plants ad vegetable crops as well as grapevine and fruit-tree plantations. The losses caused by Sorghum halepense are enormous; in case of maize and sugar beet crops, these losses reach and extremely high rate of 30-70%. For these reasons, at the University of Agricultural Sciences and Veterinary Medicine, Timisoara, city in western part of Romania, a study was made having as objects the latest herbicides synthesized in the world: Equip--which contains 22.5 g/l foramsulfuron + 22.5 g/l isoxadifen-ethyl (safener); Mais-Ter--which contains 300 g/kg foramsulfuron + 10 g/kg iodosulfuron-methyl sodium + 300 g/kg isoxadifen-ethyl (safener); Terano--which contains 600 g/kg flufenacet + 25 g/kg metasulfuron; Mistral (standard)--which contains 40 g/l nicosulfuron. Each of these herbicides (in commercial form) was applied in four doses. The best results in the control of Sorghum halepense obtained by applying the Mistral herbicide. In second place from the point of you of its efficacy came the herbicide Mais-Ter and third place the herbicide Equip. The lowest degree of efficacy was recorded by the herbicide Terano. The grain yield in case of maize crops treated with before mentioned herbicides was in strict correlation with the efficacy of the herbicides and especially with the dose applied per hectare.