RESUMO

Aquatic communities are increasingly exposed to complex mixtures of contaminants, mainly pesticides due to the impact of agricultural activity. The aim of this study was to evaluate the toxicity of an eight-pesticide cocktail on larvae of the South American common toad, Rinella arenarum. The cocktail represents a realistic mixture of insecticides (cypermethrin, chlorpyrifos and lambda-cyhalothrin), herbicides (glyphosate, glufosinate ammonium, prometryn and metolachlor), and a fungicide (pyraclostrobin) previously found in aquatic organisms (Prochilodus lineatus) from the Salado River Basin, an area with strong agricultural pressure. Computational simulations through the Density Functional Tight-Binding method indicated a strong spontaneous trend toward the formation of the cocktail, suggesting that it may act as a novel xenobiotic entity in the environment. The cocktail effects were evaluated in early-developing and premetamorphic larvae, at feasible concentrations found in real scenarios. The mixture led to high mortality and teratogenicity in early-developing larvae. Premetamorphic larvae showed endocrine disruption, oxidative stress, and impairments in detoxification and hepatic functioning. Neurotoxicity, genotoxicity, cardiotoxicity and high mortality under stress conditions were also observed in exposed larvae. This novel evaluation highlights the ecotoxicological risk for aquatic organisms exposed to complex mixtures and underscores the need to consider cocktail effects in studies regarding ecosystems health.

RESUMO

Bullfrog oil (BO), a natural product obtained from recycling of adipose tissue from the amphibian Rana catesbeiana Shaw, has been recently evaluated as a therapeutic activity ingredient. This work aimed to evaluate the long-term and accelerated thermal oxidative stabilities of this product, which is a promising raw material for emulsion technology development. BO was extracted from amphibian adipose tissue at 70 °C with a yield of 60% ± 0.9%. Its main fatty acid compounds were oleic (30.0%) and eicosapentaenoic (17.6%) acids. Using titration techniques, BO showed peroxide, acid, iodine and saponification indices of 1.92 mEq·O2/kg, 2.95 mg·KOH/g oil, 104.2 g I2/100 g oil and 171.2 mg·KOH/g oil, respectively. In order to improve the accelerated oxidative stability of BO, synthetic antioxidants butylhydroxytoluene (BHT) and buthylhydroxyanisole (BHA) were used. The addition of BHT increased the oxidation induction time compared to the pure oil, or the oil containing BHA. From the results, the best oil-antioxidant mixture and concentration to increase the oxidative stability and allow the oil to be a stable raw material for formulation purposes was derived.

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Abstract Studies of biodiversity of echinoderms from South America have increased in recent years. Here we summarize sampling done on three expeditions along the Argentinean coast (35º - 55º S) and near the Antarctic Peninsula. The first campaign, Mejillón II (M-II; 2009), was carried out between 35º - 39º S and covered a depth range between 10 to 140 m. The second was part of the Summer Antarctic Campaign 2011 (CAV-III; 2011) that took place around the Antarctic Peninsula, South Shetland and South Orkney Islands (depth range between 67 to 754 m). The last cruise was the final stretch of the Summer Antarctic Campaign 2011 (CAV-IV; 2011), from 39º - 55º S and between 30 - 140 m depth. As result, 74 stations have been studied, of which 68 had at least one echinoderm specimen. From the total number of stations, the occurrence percentages for each class were Asteroidea (68 %), Echinoidea (64 %), Ophiuroidea (55 %), Holothuroidea (51 %) and Crinoidea (20 %). In the M-II campaign, echinoderms were presented in 94 % of the sampled stations, with Echinoidea most frequent (74 %). In the CAV-III campaign echinoderms were presented in all the stations; Ophiuroidea were found in all stations. The lowest occurrence of echinoderms was found in the CAV-IV campaign (82 %), where Asteroidea was present in the 73 % of the samples, and crinoids were absent. Rev. Biol. Trop. 63 (Suppl. 2): 115-120. Epub 2015 June 01.

Resumen En los últimos años se han incrementado los estudios sobre la biodiversidad de equinodermos de Latinoamérica. En el presente trabajo, se exponen los resultados sobre muestras obtenidas en tres expediciones a lo largo de la costa argentina (35 - 55º S) y cerca de la Península Antártica. La primera campaña analizada, Mejillón II (M-II; 2009), se llevó acabo entre 35º - 39º S cubriendo profundidades entre 10 y 140 m. La segunda, parte de la Campaña Antártica de Verano 2011 (CAV-III; 2011), tuvo lugar en el área de la Península Antártica, Shetland del Sur e islas Orcadas del Sur (profundidad entre 67 hasta 754 m). La última expedición analizada en este trabajo fue el último tramo de la Campaña Antártica de Verano (CAV-IV; 2011) desde 39º - 55º S y entre 30 - 140 m de profundidad. Como resultado, 74 estaciones fueron estudiadas, en las cuales en 68 se encontró al menos un espécimen del Phylum Echinodermata. Considerando todas las estaciones, el porcentaje de encuentro para cada clase fue Asteroidea (68 %), Echinoidea (64 %), Ophiuroidea (55 %), Holothuroidea (51 %) and Crinoidea (20 %). En la campaña M-II, los equinodermos estuvieron presentes en el 94 % de las estaciones muestreadas, siendo Echinoidea el más frecuente (74 %). En relación a la Campaña CAV-III, los equinodermos estuvieron presentes en todas las estaciones muestreadas; Ophiuroidea fue la clase más representativa en número de estaciones (100 %). El valor más bajo de aparición de equinodermos fue encontrado en la campaña CAV-IV (82 %), donde Asteroidea estuvo presente en el 73 % de las muestras, y los crinoideos estuvieron ausentes.

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There are few studies about the nutritional requirements and dry matter accumulation due to the mineral nutrition of Helianthus sp. Since this plant presents a high requirement of boron it is a good indicator of the boron deficiency in the soil. A study was curried out in pots in the greenhouse to evaluate the effect of different level of lime and of boron on growth and dry matter accumulation. The soil"s pH improvement was done with lime in the folowing dosages: 15% (0 t/ha), 40% (1t/ha), 60% (2t/ha) and 80% (3t/ha) of bases saturation and the boron leveis (boric acid) were 0,1 and 2mg dm3 After 33 days of plantation the aerial part of the heilanthus plants was cut off and dried in greenhouse and, after that, evaluated in terms of dry substance yield. The increase of soil basis saturation to 40% resulted in a higher accumulation of dry substance which indicated that the 1 ton/ha dosage was considered sufficient to reach a satisfactory pH. The boron level at 1 pprn reached a higher value of dry substance which differs significantly from the helianthus yield with the absence of boron.  

Poucos são os estudos sobre as exigências nutricionais da planta de girassol. Em razão de sua exigência a esse micronutriente, o girassol é uma forte indicadora de deficiência de boro no solo. Com o objetivo de avaliar o efeito de diferentes doses de calcário e de boro na produção de matéria seca do girassol foi realizado um estudo em casa de vegetação. A correção do pH do solo foi realizada com minercaf nas seguintes dosagens 75% (O t/ha), 40% (1t/ha), 60% (2t/ha) e 80% (3t/ha) de saturação por bases e as doses de boro (ácido borico) foram 0,1 e 2 mg dm3. Após 33 dias do plantio foram colhidas as partes aéreas das plantas que foram secas em estufa e posteriormente pesadas. A elevação da saturação por bases do solo para 40% resultou em maior acúmulo de matéria seca. O nível de boro a 1 mg dm3 proporcionou maior valor de matéria seca diferindo significativamente do rendimento do girassol na ausência de boro.    

RESUMO

There are few studies about the nutritional requirements and dry matter accumulation due to the mineral nutrition of Helianthus sp. Since this plant presents a high requirement of boron it is a good indicator of the boron deficiency in the soil. A study was curried out in pots in the greenhouse to evaluate the effect of different level of lime and of boron on growth and dry matter accumulation. The soil"s pH improvement was done with lime in the folowing dosages: 15% (0 t/ha), 40% (1t/ha), 60% (2t/ha) and 80% (3t/ha) of bases saturation and the boron leveis (boric acid) were 0,1 and 2mg dm3 After 33 days of plantation the aerial part of the heilanthus plants was cut off and dried in greenhouse and, after that, evaluated in terms of dry substance yield. The increase of soil basis saturation to 40% resulted in a higher accumulation of dry substance which indicated that the 1 ton/ha dosage was considered sufficient to reach a satisfactory pH. The boron level at 1 pprn reached a higher value of dry substance which differs significantly from the helianthus yield with the absence of boron.

Poucos são os estudos sobre as exigências nutricionais da planta de girassol. Em razão de sua exigência a esse micronutriente, o girassol é uma forte indicadora de deficiência de boro no solo. Com o objetivo de avaliar o efeito de diferentes doses de calcário e de boro na produção de matéria seca do girassol foi realizado um estudo em casa de vegetação. A correção do pH do solo foi realizada com minercaf nas seguintes dosagens 75% (O t/ha), 40% (1t/ha), 60% (2t/ha) e 80% (3t/ha) de saturação por bases e as doses de boro (ácido borico) foram 0,1 e 2 mg dm3. Após 33 dias do plantio foram colhidas as partes aéreas das plantas que foram secas em estufa e posteriormente pesadas. A elevação da saturação por bases do solo para 40% resultou em maior acúmulo de matéria seca. O nível de boro a 1 mg dm3 proporcionou maior valor de matéria seca diferindo significativamente do rendimento do girassol na ausência de boro.