Biflavonoids from Podocalyx loranthoides

Analysis of the ethyl acetate extract of the aerials parts of Podocalyx loranthoides led to the isolation of I 7, II 4'-dimethylamentoflavone (1) and II 4'-methylamentoflavone (2). Compound (1) gave a moderate effect against Leishmania mexicana promastigotes.     

Insecticidal and anti-microbial activity of bio-oil derived from fast pyrolysis of lignin,cellulose, and hemicellulose

Journal of Pest Science - Conflicting views regarding synthetic pesticides include the successful use as pest management tools for agriculture and forestry on one hand and the threats to components...     

Litter production and nutrient deposition from native woody species in the Brazilian semi-arid region

Agroforestry Systems - The use of native trees in agroecosystems is a promising way to increase litter deposition and nutrient cycling and foster the recovery of degraded areas, especially in...     

Marine Sponge Derived Natural Products between 2001 and 2010: Trends and Opportunities for Discovery of Bioactives

Marine sponges belonging to the phylum Porifera (Metazoa), evolutionarily the oldest animals are the single best source of marine natural products. The present review presents a comprehensive overview of the source, taxonomy, country of origin or geographical position, chemical class, and biological activity of sponge-derived new natural products discovered between 2001 and 2010. The data has been analyzed with a view to gaining an outlook on the future trends and opportunities in the search for new compounds and their sources from marine sponges.     

Evaluation of the intrinsic competitiveness and saprophytic competence of Rhizobium tropici IIB strains

Inoculation of beans (Phaseolus vulgaris L.) with strains of R. tropici IIB and R. etli resulted in the disappearance of the R. tropici IIB stains from the nodule population and their replacement by other (non R. tropici IIB) bean symbionts (Vlassak et al. 1996). Coinoculation studies in monoxenic conditions and in soil core microcosms with plants harvested at two different growth stages indicated that the inoculated R. tropici IIB strains CIAT899 and F98.5 possess a good intrinsic competitiveness which declines, however, at a later plant growth stage and in soil conditions. The poor saprophytic competence of R. tropici IIB strain CIAT899 was further demonstrated by its poor survival in soil core microcosms after bean harvest. Strains were isolated from the field plots with a 3-year bean-planting history, characterized and evaluated for their competitiveness against R. tropici IIB strain CIAT899. Isolates from field plots, which had been repeatedly inoculated with R. tropici IIB strain CIAT899, showed a higher nodule occupancy compared to R. tropici IIB strain CIAT899, and this higher competitiveness exhibited by the field isolates might be an additional reason for the poor performance of R. tropici IIB strain CIAT899 in the field study. Plots with and without a history of bean production revealed after 3-year bean cultivation an almost totally different population that also significantly differed in competitiveness. Received: 12 February 1996     

Canine echinococcosis: an alternative for surveillance epidemiology

The essential activities for programmes of cystic echinococcosis control are the census of all dogs from the program and identification of parasitised animals. Currently, in South America evaluations and epidemiological surveillance are based on the administration of arecoline hydrobromide. This method has the disadvantage of increasing environmental pollution and risk for operators and owners of treated dogs. A genus-specific ELISA capture method has been employed for recently issued faeces and the confirmation of positive examination was performed by dog autopsies. Our work presents an alternative method based on collection of dry field-dispersed faeces, followed by serological diagnosis by Copro-ELISA and confirmation by Copro-Western blot. If Copro-ELISA were used to define positive samples of dry faeces, the Copro-Western blot assay would provide 70% sensitivity and 100% specificity. Global efficiency of the system using dry faeces would reach 76%, allowing epidemiological surveillance to be oriented to analysis of surface units instead of dog as measurement unit.     

Histological alterations in gills of shrimp Litopenaeus vannamei in low‐salinity waters under different stocking densities: Potential relationship with nitrogen compounds

Two experimental modules with different stocking densities (M1 = 70 and M2 = 120 shrimp /m²) were examined weekly over a culture cycle in tanks with low‐salinity water (1.9 g/L) and zero water exchange. Results showed survival rates of 87.7 and 11.9% in M1 and M2, respectively. Water temperature, pH, dissolved oxygen, electrical conductivity and chlorophyll a were not significantly (p > .05) different between modules. In contrast, the concentrations of nitrogen compounds were significantly (p < .05) different between modules, except nitrite‐N (M2 were 2.31 ± 1.38 mg/L N‐TAN, 0.18 ± 0.49 mg/L N‐NO₂^? and 6.83 ± 6.52 mg/L N‐NO₃^?; in M1: 0.97 ± 0.73 mg/L N‐TAN, 0.05 ± 0.21 mg/L N‐NO₂^? and 0.63 ± 0.70 mg/L N‐NO₃^?). When waters of both modules reached higher levels of ammonia and nitrite, histological alterations were observed in gills. The histological alterations index (HAI) was higher in M2 (5‐112) than in M1 (2‐22).     

Effects of diluted and undiluted treated wastewater on the growth,physiological aspects and visual quality of potted lantana and polygala plants

In many nurseries in the Mediterranean area irrigation water supply is a major problem due to climatic conditions, and it is important to evaluate alternative water resources, such as treated wastewater, for ornamental plant production. For this reason, a nursery study was conducted in order to determine: (1) the effect of irrigation with a saline reclaimed wastewater (reused water) on the growth and visual quality of Lantana camara and Polygala myrtifolia, and (2) the effectiveness of the mixing the same water with canal water to reduce any negative effects observed with the reused water. Potted plants were irrigated with reused water, canal water and reused water diluted 50% with canal water. The results suggest that polygala can be irrigated with reused water since visual damage is minimal and growth reduction very slight, which seems to be related with the plant's low accumulation of saline ions. In lantana, reused water led to an excessive uptake of chloride, sodium and boron in the leaves, which was associated with defoliation, leaf burn, leaf chlorosis and damage to the photosynthetic apparatus, diminishing both growth and its aesthetic value. The dilution of reused water alleviated some negative effects in lantana, but not sufficiently to avoid a significant loss of plant quality.