Physico-chemical and antioxidant properties of six apple cultivars (Malus domestica Borkh) grown in southern Brazil

The objective of this study was to compare the physico-chemical properties and antioxidant activity of six apple cultivars grown in southern Brazil. Apple peel color, dry matter, total soluble solids, pH, total sugars, titratable acidity, total phenolics, total monomeric anthocyanin and total antioxidant activity were measured in the apple cultivars Imperatriz, Daiane, Fred Hough, Fuji Suprema, Galaxy and Baronesa. The results showed great quantitative differences in the composition of the apple cultivars. Of all the cultivars, the peel of Galaxy was slightly more red-colored and that of Fred Hough was the least red-colored. The dry matter varied from 15.24% (Galaxy) to 19.55% (Fuji Suprema), the soluble solids content was between 11.8 (Fred Hough) and 14.0 (Daiane) °Brix, pH values varied from 3.90 (Imperatriz) to 4.27 (Fred Hough), the total sugar content (g 100 g⁻¹) ranged from 11.54 (Imperatriz) to 14.78 (Fuji Suprema) and the titratable acidity content (g 100 g⁻¹) varied from 0.20 (Baronesa) to 0.36 (Imperatriz). The total phenolic content (GAE 100 g⁻¹ fresh matter) observed in the apple cultivars was between 105.4 (Baronesa) and 269.7 mg (Imperatriz). The values of the total anthocyanin content (mg 100 g⁻¹ FM) ranged from 4.79 (Fred Hough) to 41.96 (Galaxy). The highest total antioxidant activity was observed in Imperatriz (739 μmol TEAC 100 g⁻¹ FM), while the lowest value was found in Fuji Suprema (335 μmol TEAC 100 g⁻¹ FM). There was a strong correlation between total monomeric anthocyanin content and all peel color measurements and between antioxidant activity and total phenolic content. The results suggested that genotype is the main factor that determines the composition of bioactive compounds in apples and this provides important information on how to make the best use of the apple cultivars investigated.     

P‐30 Use of fipronil for treatment of Lynxacarus radovskyi in outdoor cats in Rio de Janeiro (Brazil)

The aim of this study was to report 20 cases of Lynxacarus radovskyi infestationin 20 cats. Lynxacarus radovskyi was diagnosed by physical examination and microscopic examination of plucked hair where countless adult mites and immature stages were identified. Microscopic examination was repeated every 7 days. The animals were observed daily for the first 7 days, and again on day 15 and day 30 for mites, pruritus and clinical signs. Clinical signs included salt‐and‐pepper appearance to a dull and opaque hair coat, alopecia of the dorsal and lateral areas of the hind limbs, and evidence of self‐mutilation. One case had papules and crusts of the hind limbs. The pruritus was mild in animals with low infestation, but very intense in those with a heavy infestation. Most mites occurred in the lateral area of the hind limbs and sacral area. Twenty of 100 animals had confirmed L. radovskyi infestation. Therefore, we suggest that the transmission occurs through fomites. Treatment consisted of 0.5 mL application of Fipronil^® (Frontline TopSpot) per cat, with resolution in 100% of cases by day 15. Funding: Merial.     

Mineralogy and Arsenic Mobility in Arsenic-rich Brazilian Soils and Sediments (11 pp)

Background   Soils and sediments in certain mining regions of Brazil contain an unusually large amount of arsenic (As), which raises concerns that mining could promote increased As mobility, and thereby increase the risks of contaminating water supplies. Objectives   The purpose of this study was to identify the most important factors governing As mobility in sediments and soils near three gold-mining sites in the State of Minas Gerais, Brazil. Methods   Surface and sub-surface soil samples were collected at those sites and characterized by chemical and mineralogical analyses. Oxalate (Feo) and citrate-bicarbonate-dithionite (Fed) iron contents were determined by atomic absorption spectroscopy (AAS). Arsenic mobilization was measured after incubating the samples in a 2.5 mM CaCl2 solution under anaerobic conditions for 1, 28, 56, 84, or 112 days. The solution concentrations of As, Fe, and Mn were then measured by inductively coupled plasma-mass spectrometry (ICP-MS) and AAS, respectively. Results and Discussion   Results indicated that As mobilization is largely independent of both the total As and the Feo/Fed ratio of the solid phase. Soluble As is roughly controlled by the Fe (hydr)oxide content of the soil, but a closer examination of the data revealed the importance of other highly weathered clay minerals and organic matter. Large amounts of organic matter and a low iron oxide content should favor As leaching from soils and sediments. Under reducing conditions, As is mobilized by the reductive dissolution of Fe and/or Mn oxides. However, released As may be readsorbed depending on the sorptive properties of the soil. Gibbsite is particularly effective in adsorbing or readsorbing As, as is the remaining unreduced fraction of the iron (hydr)oxides. Conclusion and Outlook   In general, low soluble As is related to the presence of gibbsite, a large amount of iron oxides, and a lack of organic matter in the solid phase. This has environmental significance because gibbsite is thermodynamically more stable than Fe oxides under anaerobic conditions, such as those found in waterlogged soils and lake sediments.     

Growth and nutritional disorders of coffee cultivated in nutrient solutions with suppressed macronutrients

The objective was to evaluate the effect of omitting macronutrients in the nutrients solution on growth characteristics and nutritional status of coffee. The treatments were complete nutrients solutions and solutions with nutrient omission: N (nitrogen), P (phosphorus), K (potassium), Ca (calcium), Mg (magnesium) and S (sulfur). The experiment was carried out under greenhouse conditions with 3 replicates in a completely random design. Plant height, number of leaves per plant, stem diameter, relative chlorophyll index, photosynthesis rate, stomatal conductance, transpiration, carbon dioxide (CO₂) concentration, dry matter, content levels of macronutrients in plant aerial part and root system, and nutritional disorders were evaluated. Macronutrients suppression affected nutrients concentration in many plant parts, inducing the appearance of symptoms characteristic of each nutrient. The most limiting nutrients for coffee plants development were nitrogen and calcium, reflected in the lower dry matter accumulation and nitrogen the most required.     

Macronutrient omission and the development and nutritional status of basil in nutritive solution

The correct nutrition of basil (Ocinum basilicum L.) is important to increase its production and quality; however, few papers have deal with this subject. The aim of this work was to evaluate the effects of omission of individual macronutrients on the growth and nutritional status of basil cultivated in nutritive solution. The treatments consisted of nutrient solutions with nitrogen, phosphorus, potassium, calcium, magnesium or sulfur (N, P, K, Ca, Mg, or S) omissions and a complete solution treatment. The plants were cultivated in 8 L plant pots. Plant height, number of leaves per plant, leaf area, relative chlorophyll index, net photosynthesis rate, stomatal conductance, plant dry matter, concentration levels of macronutrients in the aerial part and root system, and nutritional disorders were all evaluated. Nutrient omission was a limiting factor for plant development, substantially reducing its growth. There was also a considerable decrease in nutrient accumulation when compared to the control treatment.     

Evaluating irrigation performance in a Mediterranean environment

Assessment of irrigation performance is a prerequisite for improving water use in the agricultural sector to respond to perceived water scarcity. Between 1996 and 2000, we conducted a comprehensive assessment of the performance of the Genil–Cabra irrigation scheme (GCIS) located in Andalusia, southern Spain. The area has about 7,000 ha of irrigated lands distributed in 843 parcels and devoted to a diverse crop mix, with cereals, sunflower, cotton, garlic and olive trees as principal crops. Irrigation is on demand from a pressurized system and hand-moved sprinkler irrigation is the most popular application method. Six performance indicators were used to assess the physical and economic performance of irrigation water use and management in the GCIS, using parcel water-use records and a simulation model. The model simulates the water-balance processes on every field and computes an optimal irrigation schedule, which is then checked against actual schedules. Among the performance indicators, the average irrigation water supply:demand ratio (the ratio of measured irrigation supply to the simulated optimum demand) varied among years from 0.45 to 0.64, indicating that the area is under deficit irrigation. When rainfall was included, the supply:demand ratio increased up to 0.87 in one year, although it was only 0.72 in the driest year, showing that farmers did not fully compensate for the low rainfall with sufficient irrigation water. Nevertheless, farmers in the area made an efficient use of rainfall, as indicated by the relatively high values (0.72–0.83) for the ratio of actual:attainable crop yields. Water productivity (WP) in the GCIS oscillated between 0.72 €/m³ and 1.99 €/m³ during the 4 years and averaged 1.42 €/m³ of water supplied for irrigation, while the irrigation water productivity (IWP) averaged 0.63 €/m³ for the period studied. WP is higher than IWP because WP includes production generated by rainfall, while IWP includes only the production generated by irrigation.Communicated by A. Kassam     

Silver-catalyzed C-C bond formation between methane and ethyl diazoacetate in supercritical CO₂

Even in the context of hydrocarbons' general resistance to selective functionalization, methane's volatility and strong bonds pose a particular challenge. We report here that silver complexes bearing perfluorinated indazolylborate ligands catalyze the reaction of methane (CH(4)) with ethyl diazoacetate (N(2)CHCO(2)Et) to yield ethyl propionate (CH(3)CH(2)CO(2)Et). The use of supercritical carbon dioxide (scCO(2)) as the solvent is key to the reaction's success. Although the catalyst is only sparingly soluble in CH(4)/CO(2) mixtures, optimized conditions presently result in a 19% yield of ethyl propionate (based on starting quantity of the diazoester) at 40°C over 14 hours.     

Effects of synbiotic-based Bifidobacterium animalis in female rats experimentally infected with Toxoplasma gondii

The aim of this study was to assess the effects of a synbiotic composed of Bifidobacterium animalis and fructooligosaccharides on female rats infected with Toxoplasma gondii. Female Wistar rats, treated or not with dexamethasone, were daily supplemented with synbiotics for 21 days. After 15 days of supplementation, the rats were orally infected with 10⁴T. gondii bradyzoites. Blood samples were collected to measure the levels of IFN-γ, IL-10 and T. gondii antibodies. All synbiotic-supplemented rats survived until the end of the experiment; however, non-supplemented dexamethasone-treated rats died between the fifth and the eighth days after T. gondii infection. Dexamethasone-treated rats supplemented with synbiotics (P < 0.05) were capable of synthesizing IFN-γ, and this immunological response was essential to ensure their survival. In addition, brain cysts were found in one rat not supplemented with synbiotics. Results suggest that the synbiotic composed of B. animalis and fructooligosaccharides may be beneficial to toxoplasmosis control.