Screening study of lead compounds for natural product-based fungicides: antifungal activity and biotransformation of 6alpha,7alpha-dihydroxy-beta-himachalene by Botrytis cinerea

Eleven beta-himachalene derivatives were tested, using the poisoning food technique, for their potential antifungal activity against the phytopathogen Botrytis cinerea. Compounds 1-11 displayed moderate activity, whereas the 6,7-diol derivative (12) produced an inhibition of 91% after 6 days. The microbial transformation of 12 was investigated and yielded four new compounds hydroxylated at positions C-5 (13), C-2 (14), C-4 (15), and C-12 (16). The structures were established on the basis of their spectroscopic data including two-dimensional NMR analysis (HMQC, HMBC, nOesy) and nOes. The results obtained from biotransformation experiments shed further light on the detoxification mechanism of the phytopathogenic fungus against this compound and give an indication of the structural modifications that may be necessary if substrates of this type are to be further developed as selective fungal control agents for B. cinerea.     

Determination of baseline susceptibility of European populations of Tuta absoluta (Meyrick) to indoxacarb and chlorantraniliprole using a novel dip bioassay method

BACKGROUND: Tuta absoluta(Meyrick) is one of the most serious pests of tomato recently introduced in the Mediterranean region. A novel bioassay method designed for the accurate determination of insecticide toxicity on T. absoluta (IRAC method No. 022) was validated by three different laboratories [Greece (NAGREF), Italy (UC) and Spain (UPCT)] on European populations. RESULTS: The insecticides indoxacarb and chlorantraniliprole were used as reference products. The IRAC leaf dip method is easy to perform, producing repeatable, homogeneous responses. LC₅₀ values for indoxacarb ranged between 1.8 and 17.9 mg L^?1 (NAGREF), 0.93 and 10.8 mg L^?1 (UC) and 0.20 and 0.70 mg L^?1 (UPCT), resulting in a tenfold, 12‐fold and fourfold difference between the least and most susceptible populations at each laboratory respectively. For chlorantraniliprole, LC₅₀ values ranged between 0.10 and 0.56 mg L^?1 (NAGREF), 0.23 and 1.34 mg L^?1 (UC) and 0.04 and 0.24 mg L^?1 (UPCT), resulting in a sixfold difference in all three cases. Overall, UPCT reported lower mean LC₅₀ to indoxacarb, while UC reported higher LC₅₀ to chlorantraniliprole. CONCLUSIONS: The new bioassay is reliable, providing a useful tool in the design of IRM strategies. Within each country/lab, the variability observed in the results for both indoxacarb and chlorantraniliprole can be attributed to natural variation. Future research is necessary to determine the extent to which it is possible to compare results among laboratories. Copyright © 2012 Society of Chemical Industry     

Variability of hair coat and skin traits as related to adaptation in Criollo Limonero cattle

The variation in hair coat and skin histology traits of Criollo Limonero cattle was analyzed using 213 Criollo Limonero females. Skin biopsies were obtained from slick-haired (N = 16) and normal-haired (N = 14) animals. Measured traits included hair length (HL), color coat (CC), number of hair follicles per square centimeter (NHF), sweat glands per square centimeter (NSG), sweat glands size (SGS), sebaceous glands per square centimeter (NSBG), blood vessels per square centimeter (NBV), and thickness of epidermis (TE). Hair length differed (P < 0.001) between slick- and normal-haired animals (4.9 ± 0.12 vs 10.9 ± 0.20, respectively). Differences (P < 0.01) in CC (Bayo = 144/67.6% vs Red = 69/32.4%) and HL (slick-haired = 199/93.4% vs normal-haired = 14/6.5%) were found. Distribution of slick- and normal-haired animals differed (P < 0.01) between bayo-coated and red-coated (139/62.2% vs 9/4.2%; respectively). Most (P < 0.05) red-coated animals belonged to a single family. No differences (P > 0.05) were found between slick-haired and normal-haired animals in NHF (637 ± 164 vs 587 ± 144, respectively), NSG (556 ± 134 vs 481 ± 118, respectively), NSBG (408 ± 87 vs 366 ± 77, respectively), NBV (1628 ± 393 vs 1541 ± 346, respectively), and TE (1.24 ± 0.14 vs 1.32 ± 0.12, respectively). However, SGS was greater (P < 0.01) in slick-haired than normal-haired animals. In conclusion, Criollo Limonero cattle are predominantly bayo-coated, slick-haired, with a reduced number of hair follicles relative to Zebu cattle, sweat and sebaceous glands in proportion to hair follicle numbers, and with a high blood flow irrigating the skin. There is a sub-group of red-coated animals with yellow or cream skin, thicker epidermis, and with a higher frequency of normal-haired animals. It appears that the slick hair gene has been favored by natural selection in this breed.     

Soil Contamination in Dumps on the Karstic Areas from the Plateaus (Southeast of Madrid, Spain)

After over 10 years of accumulation of residues in the studied dumps near Madrid, it has been registered low or moderate heavy metals concentrations on the surrounding area. Only occasionally, some rubbish dumps contain significant quantities of Cu, Ni, Zn and Pb. The concentration levels of Pb, Ni, Zn and Cu are safe when they are compared with the surrounding areas levels of heavy metals. The aim of this paper is the analysis of pollutants existing around in the dumps located at the sides of the plateaus of the central valley of the Tajo River (provinces of Madrid and Toledo, Spain). The high karstification rate of the upper layer of these tablelands and the existence of numerous dumps on them (even on their slopes) make these areas vulnerable to heavy metal pollution. However, after several years of use, the concentration of pollutants only reaches moderate values in the studied areas. Dumping materials were collected at four rubbish dumps. The mineralogical composition of the materials were analysed by XRD. Sequential extraction procedure was applied for speciation of the metal forms in the collected samples. Concentrations of Zn, Pb, Ni, Cu, Cr and Cd in extracts were determined by AAS. The studied samples showed high carbonate concentration. Contamination processes are combined there with weathering processes. Heavy metals concentration in control samples (gypsum, limestones, red soils and colluviums) were compared with samples of the studied dump in order to evaluate the pollution level. Concentrations of Zn, Pb, Ni and Cu were variable. The contamination was elevated for samples in depth in relation with weathering process of heavy metals.     

Treatment of canine Alopecia X with trilostane

Sixteen Pomeranians and eight miniature poodles presenting with clinical signs of alopecia X, elevated blood concentrations of 17-hydroxyprogesterone post stimulation with adrenocorticotropic hormone and increased urinary cortisol/creatinine ratios were treated with trilostane, a competitive inhibitor of 3beta-hydroxysteroid dehydrogenase. Trilostane was given once or twice daily at a mean dose of 10.85 mg kg(-1) day(-1). Adrenal function was evaluated with a follow-up of 28 months in the Pomeranians and 33 months in the miniature poodles. Treatment with trilostane led to complete hair re-growth in 85% of the Pomeranians and in all of the miniature poodles within 4 to 8 weeks. No adverse events attributed to treatment with trilostane were recognized. The hair re-growth might have been the result of a down-regulation of adrenal steroids and/or of the noncompetitive inhibition of the oestrogen receptors at the hair follicle level.     

Relative Contribution of Nitrogen and Sulphur to Deposition Acidity and Regional Modelling in Lake Maggiore Watershed (Southern Alps,Switzerland and Italy)

Water, Air, & Soil Pollution - Over the last 20 years wet deposition chemistry in the Lake Maggiore watershed has been studied at 13 sites distributed at different altitudes throughout the...