Evolution of Carotenoids,Sensory Profiles and Volatile Compounds in Microwave-Dried Fruits of Three Different Loquat Cultivars (Eriobotrya japonica Lindl.)

Plant Foods for Human Nutrition - The consumption of loquat fruits is highly appreciated for their carotenoid content and valuable sensory notes, but it is limited due to the low shelf-life. An...     

Haematological and oxidative stress responses in Piaractus mesopotamicus under temperature variations in water

In this study, the influence of temperature variation on the blood and oxidative stress parameters of pacu Piaractus mesopotamicus juveniles was evaluated. Fish were subjected to gradual changes of temperature, over 5 days, by 24°C until reaching to experimental temperatures 18, 21, 24 (control), 27 and 30°C. There were significant differences (p < .05) in glucose and lactate of blood in both the haematological relationships and oxidative stress parameters. Glucose levels increased at 30°C and decreased at 21°C. Lactate levels were highest at 18°C. While the haematocrit was higher at all altered temperatures, haemoglobin levels decreased at 21°C and increased at 30°C, causing alterations in haematimetric indices. In the liver, glutathione‐S‐transferase (GST) activity was reduced at 18°C while antioxidant capacity against peroxyl radicals (ACAP) was highest at 30°C. Thiobarbituric acid reactive substances (TBARS) increased at 18, 21 and 27°C. In the muscle, ACAP decreased at 27 and 30°C and TBARS increased at 30°C. The results indicate that the species shows sensitivity to temperature variations. Accordingly, we conclude that with short‐term temperature variations >3°C, it is possible to induce higher alterations in the observed parameters in pacu juveniles.     

Daily rhythms of cortisol and glucose and the influence of the light/dark cycle on anaesthesia in Nile tilapia (Oreochromis niloticus): Does the timing of anaesthetic administration affect the stress response?

Although daily variations in drug pharmacokinetics have been reported for a variety of teleost species, the influence of this daily variation on the cortisol response following anaesthesia remains poorly understood. To address this, two experiments were performed. The first experiment described the daily patterns of cortisol and glucose secretion in tilapia (Oreochromis niloticus). The second experiment investigated how the timing of anaesthetic administration (specifically at mid‐light [ML] or at mid‐dark [MD]) affects the induction and recovery times and plasma cortisol and glucose levels of juvenile Nile tilapia exposed to benzocaine, clove oil or tricaine methanesulphonate (MS‐222). The results revealed that the effect on the stress response associated with the moment when anaesthesia took place (ML or MD) varied according to the treatment (p < 0.05). Cortisol levels were significantly higher at ML for MS‐222 (ML = 116.23 ± 25.55; MD = 48.25 ± 22.33 ng/dl) (p < 0.05) and clove oil (ML 59.73 ± 14.27; MD 38.26 ± 12.07 ng/dl) (p < 0.05), whereas no significant differences were found between ML and MD cortisol levels for the control treatment (ML = 72.91 ± 18.42; MD = 64.80 ± 10.68 ng/dl) (p > 0.05) or in the benzocaine‐treated group (ML = 38.7 ± 4.90; MD = 38.60 ± 3.69 ng/dl) (p > 0.05). The highest plasma cortisol level in ML was found in the MS‐222‐treated group. All the tested anaesthetics had similar cortisol levels at MD (p > 0.05).     

Characterization of Open-Pollinated Maize Varieties from Rio Grande do Sul State

Journal of Crop Science and Biotechnology - The morphological characterization allows one to estimate and evaluate the genetic distance among different varieties, identifying heterotrophic groups...     

Artificial structures as tools for fish habitat rehabilitation in a neotropical reservoir

• 1. Since most of the natural habitats critical for freshwater fish survival have been adversely affected by human disturbance, the effectiveness of artificial structures in providing new and suitable habitats for fish has been increasingly investigated.
• 2. This paper evaluates the role of artificial structures as fish habitat in a structureless 30 km² Brazilian reservoir, through underwater surveys conducted monthly from April 1999 to March 2000.
• 3. In total, 5759 fish in nine species were recorded, but only three cichlid species—one native, Geophagus brasiliensis and two non‐native, Cichla kelberi and Tilapia rendalli—showed consistent association with the artificial habitats, suggesting that this family reacts to submerged structures.
• 4. The absence of fish at control sites compared with high occurrences in sites provided with a physically complex structure suggests that artificial structures can play an important ecological role for cichlids smaller than 150 mm TL, probably related to shelter and/or feeding benefits.
• 5. The level of structural complexity and position in the water column influenced fish use of artificial structures. C. kelberi was associated with highly complex structures, whereas moderately complex bottom structures were more effective in harbouring G. brasiliensis. Bottom structures are apparently more important than midwater structures in harbouring T. rendalli, but structural complexity seemed to play a secondary role.
• 6. This study is the first in demonstrating that adding complex artificial structures can expand habitats for small fish (<150 mm TL), especially cichlids, in a neotropical impoundment. It seems reasonable to expect that deploying physically complex structures in other oligotrophic, structureless and cichlid‐dominated impoundments in Brazil will lead to similar results to those found in this work.

Copyright © 2008 John Wiley & Sons, Ltd.     

Vector analysis in the study of the nutritional status of Philodendron cultivated in compost-based media

Compost (CP) made from 70% ligno-cellulosic compounds and 30% sewage sludge was studied as a component of growing media in a 6-month Philodendron cultivation. CP's agronomic viability was evaluated via four plant-growth media containing 25–50–75–100% CP and white sphagnum peat (WP) in comparison to a commercial substrate with white and black peat. Plant nutrition conditions were investigated by determining macro- (TKN, P, K, Ca, Mg and micronutrients (Mn, Fe, Cu, Zn, Na) and heavy metals (Ni, Cd, Cr, Pb) in roots and shoot tissues. Data were compared by vector analysis against control. Even if no leaf injuries were visible after 6-months’ growth, a CP ratio of up to 50% caused growth depression of canopy tissues, as attested by the 37 and 36% reduction in total leaf dry weight and leaf area, respectively. Root growth decline was also notable at 25% CP, where 38% root dry weight reduction implied a significant increase (46%) in shoot–root dry weight ratio. The investigation on nutrient tissue content showed high accumulation of Ni, Fe, Cr, Zn, Cd, Mn, Mg and P in roots; Mg appeared related to K deficiency. Above-ground nutritional status showed a severe lack of P, Mg and Mn. Vector analysis suggests the sewage sludge CP in Philodendron pot cultivation produces many such effects like direct toxic action and antagonistic action, resulting in a general nutrient imbalance in plants.     

Biological and biochemical characterization of isolates of Trypanosoma evansi from Pantanal of Matogrosso--Brazil

Ten isolates of Trypanosoma evansi from the Pantanal region of Brazil, recently derived from coati (Nasua nasua, carnivora, Procyonidae), horses and dogs, were characterized on the basis of biological (experimental infections in Wistar rats) and biochemical (multilocus enzyme eletrophoresis) data. Biological data were analyzed by Nested analysis of variance and Kruskal-Wallis. Marked heterogeneity in virulence was observed in the isolates. Some of the isolates showed an undulating parasitaemia, typical for African trypanosomes. This biological heterogeneity did not correspond with the biochemical homogeneity observed in the T. evansi isolates. T. evansi has one of the widest distributions and greatest range of mammalian hosts and is widely recognized to have evolved from Trypanosoma brucei. Adaptability of T. evansi was not reflected in the variability of biochemical and molecular parameters studied to date. The variability in virulence was very significant, but not correlated with the host from which it was derived. These data suggested that, in the region studied, T. evansi is transmitted among both domestic and sylvatic animals in one single transmission cycle.     

Biological activity of neolignans on the post-embryonic development of Chrysomya megacephala

Phytochemicals endowed with hormonal, antihormonal, or toxic activity are potential agents for insect control. The effect of some neolignans on one of the most prevalent flies in urban areas, which constitutes a menace to public health, was investigated.     

Anti-leishmanial and immunomodulatory activities of extracts from Portulaca hirsutissima and Portulaca werdermannii

Ethyl acetate and chloroform extracts from aerial parts of Portulaca werdermannii and P. hirsutissima were tested in lymphoproliferation assays and axenic cultures of Leishmania amazonensis and Trypanosoma cruzi. Both extracts of P. werdermannii and P. hirsutissima had a potent inhibitory activity on lymphocyte proliferation. On the contrary, only the chloroformic extract of both plants inhibited L. amazonensis growth, without effect on T. cruzi cultures. These results indicate these Portulaca species as potential sources of new active molecules for the treatment of leishmaniasis and immune-mediated pathologies.