Residue levels and storage decay control in Cv. Star Ruby grapefruit after dip treatments with azoxystrobin

Cv. Star Ruby grapefruit (Citrus paradisi Macf.) were subjected to a 3-min dip in water at room temperature (20 degrees C) or at 50 degrees C with or without 25, 50, or 100 mg/L azoxystrobin (AZX). Then, the fruits were subjected to cold quarantine at 2 degrees C and 90-95% relative humidity (RH) for 3 weeks and then stored for 5 weeks at 8 degrees C and approximately 85% RH and for another 2 weeks at 20 degrees C and 80% RH to simulate a 2-week marketing period (SMP). No AZX residues were detected in the albedo and pulp following treatments at 20 or 50 degrees C, the total amount of residues being recovered from the flavedo tissue. There was a relationship between the AZX uptake in fruit and the amount of fungicide employed at 20 or 50 degrees C. When AZX was applied to the fruit at 25 mg/L at 20 degrees C, the residue level averaged 0.11 mg/kg (active ingredient, whole fruit basis). This residue concentration increased by 50 and 75% when the application rate increased from 25 to 50 or 100 mg/L, respectively. A similar pattern of accumulation was detected in fruit subjected to treatments at 50 degrees C. However, treatments at 50 degrees C produced residue levels higher than the treatments at 20 degrees C, with increases ranging from 63 to 84%, for the same concentration. Storage conditions did not affect the amount of AZX residues in the fruit. Treatment at 50 or 100 mg/L at 20 degrees C reduced the incidence of moderate to severe chilling injury (CI). Water dips at 50 degrees C reduced the incidence and severity of CI to a very low extent, with no additional advantages when hot water was used in combination with AZX. Treatments with 50 or 100 mg/L of AZX at 20 degrees C produced beneficial effects in decay control similar to those of 25 mg/L AZX at 50 degrees C or hot water alone. Better results were achieved with 50 or 100 AZX at 50 degrees C, providing complete control of decay during cold storage and with negligible decay after SMP. It was concluded that when AZX was applied at 50 degrees C, low doses of fungicide and minimal residue levels in fruit were required to control the postharvest decay of grapefruit. This treatment does not impair fruit quality and offers very interesting prospects for large scale application, due to the reduced potential toxicity of AZX to nontarget organisms and to the environment.     

Leucettamols, Bifunctionalized Marine Sphingoids, Act as Modulators of TRPA1 and TRPM8 Channels

Leucettamols, bifunctionalized sphingoid-like compounds obtained from a marine sponge Leucetta sp., act as non-electrophilic activators of the TRPA1 channel and potent inhibitors of the icilin-mediated activation of the TRPM8 channel, while they are inactive on CB₁, CB₂ and TRPV1 receptors. Leucettamols represent the first compounds of marine origin to target TRPA1 and the first class of natural products to inhibit TRPM8 channels. The preparation of a small series of semi-synthetic derivatives revealed interesting details on the structure-activity relationships within this new chemotype of simple acyclic TRP modulators.     

In vitro release of angiotensin-converting enzyme inhibitors, peroxyl-radical scavengers and antibacterial compounds by enzymatic hydrolysis of glycated gluten

The combined effect of gluten glycation and proteolysis on the release of compounds exhibiting in vitro angiotensin-converting enzyme (ACE) inhibitory, antioxidant and antibacterial activities was investigated. Model systems consisting of wheat gluten and glucose were heated at 120 °C for 45 min, 150 °C for 30 min and 220 °C for 30 min to produce various Maillard reaction products mimicking reactions occurring in bread crusts. Progress of the Maillard reaction was estimated through indirect measurement of Amadori compounds as 2-furoylmethyl-amino acids. Glycation was followed by digestion with Pronase E and ultrafiltration. The anti-hypertensive activity was measured as the ability to inhibit the activity of angiotensin I-converting enzyme involved in hypertension regulation. The Oxygen Radical Absorbance assay was used to measure the peroxyl radical scavenging capacity of the products and their effect on microbial growth of Escherichia coli ATCC 25922 and Staphlococcus aureus ATCC 25923 was also studied. Advanced products of the reaction enhanced the antioxidant and antibacterial properties of gluten hydrolysates and decreased the overall ACE inhibitory activity. Ultrafiltration provided a useful method for separating compounds (< 3000 Da) with ACE inhibitory activity and advanced Maillard reaction products (>3000 Da) which scavenged peroxyl radicals and inhibited the microbial growth.     

Relationship between virgin olive oil phenolic compounds and acrylamide formation in fried crisps

In this paper the relationship between virgin olive oil (VOO) phenol compounds and the formation of acrylamide in potato crisps was investigated. The phenol compositions of 20 VOO samples were screened by LC-MS, and 4 oils, characterized by different phenol compound patterns, were selected for frying experiments. Slices of potatoes were fried at 180 degrees C for 5, 10, and 15 min, and acrylamide content was determined by LC-MS. Results demonstrated that VOO phenolic compounds are not degraded during frying, and crisp color was not significantly different among the four VOOs. Acrylamide concentration in crisps increased during frying time, but the formation was faster in the oil having the lowest concentration of phenolic compounds. Moreover, the VOO having the highest concentration of ortho-diphenolic compounds is able to efficiently inhibit acrylamide formation in crisps from mild to moderate frying conditions. It was concluded that the use of ortho-diphenolic-rich VOOs can be proposed as a reliable mitigation strategy to reduce acrylamide formation in domestic deep-frying.     

Effect of different levels of dietary sweet orange (Citrus sinensis) peel extract on humoral immune system responses in broiler chickens

This experiment was conducted to evaluate the effects of different levels of sweet orange (Citrus sinensis) peel extract (SOPE) on humoral immune system responses in broiler chickens. Three hundred 1‐day broilers (Ross‐308) were randomly allocated to treatments varying in supplemental SOPE added in the drinking water. The experimental groups consisted of three treatments fed for 42 days as follows: a control treatment without feed extract, a treatment containing 1000 ppm of SOPE and a treatment containing 1250 ppm of SOPE. All treatments were isocaloric and isonitrogenous. Broilers were vaccinated with Newcastle disease virus (NDV), avian influenza (AI), infectious bursal disease (IBD) and infectious bronchitis virus (IBV) vaccines. Antibody titer response to sheep red blood cells (SRBC) was higher in the group fed 1250 ppm of SOPE (P < 0.05) as well as for immunoglobulin G (IgG) and IgM. Similarly, antibody titer responses to all vaccines were constantly elevated (P < 0.05) by SOPE enrichment in a dose‐dependent manner. Relative weights of spleen and bursa of Fabricius were unaffected by treatments. Dietary SOPE supplementation may improve the immune response and diseases resistance, indicating that it can constitute a useful additive in broiler feeding. Thus, supplying SOPE in rations may help to improve relative immune response in broiler chickens.     

Body condition score prior to parturition is associated with plasma and adipose tissue biomarkers of lipid metabolism and inflammation in Holstein cows

Background: Previous research has revealed a strong inflammatory response within adipose(AT) tissue during the transition into lactation. Whether this effect is a result of oxidative stress induced by lipolysis and fatty acid oxidation associated with differences in prepartum body condition score remains to be determined. The objectives of this study were to investigate systemic biomarkers of energy balance and inflammation and the expression of lipid metabolismand inflammation-related genes in AT during the transition period in dairy cows.Results: Twenty multiparous Holstein cows were retrospectively divided by body condition score(BCS) prior to parturition into two groups(10 cows/group): BCS ≤ 3.25(Lo BCS) and BCS ≥ 3.75(Hi BCS). Subcutaneous adipose tissue was biopsied from the tail-head region at d-10, 7 and 20 relative to parturition. Plasma was used to evaluate biomarkers of energy balance(EBAL) [free fatty acids(NEFA), glycerol, insulin] and inflammation [IL-1β, haptoglobin, myeloperoxidase, and reactive oxygen metabolites(ROM)]. Although insulin concentration was not affected by BCS, NEFA was overal greater and glycerol lower in HiB CS cows. Greater activity of myeloperoxidase in plasma coincided with increased haptoglobin and IL-1β postpartum in LoB CS cows.Among genes related with oxidative stress, the expression of the cytosolic antioxidant enzyme SOD1 was greater in LoB CS compared to HiB CS. Cows in LoB CS compared with HiB CS had greater overal expression of ABDH5 and ATGL along with ADIPOQ, indicating enhanced basal lipolysis and secretion of adiponectin. Expression of CPT1 A, ACADVL, and ACOX1 was greater overal in HiB CS than LoB CS indicating enhanced NEFA oxidation. Although the temporal increase in plasma NEFA regardless of BCS coincided with the profile of CPT1 A, the gradual decrease in genes related with reesterification of NEFA(PCK1) and glycerol efflux(AQP7) coupled with an increase in glycerol kinase(GK) suggested some stimulation of NEFA utilization within adipose tissue. This idea is supported in part by the gradual decrease in insulin regardless of BCS. Although expression of the inflammation-related gene toll-like receptor 4( TLR4) was greater in Hi BCS versus Lo BCS cows at-10 d, expression of TLR9 was greater in Hi BCS versus Lo BCS at 20 d.These profiles did not seem to be associated with concentrations of pro-inflammatory biomarkers or ROM.Conclusions: Overall, data indicated that cows with BCS 3.25 or lower before calving experienced greater alterations in systemic inflammation and basal lipolysis without excessive increases in NEFA plasma concentrations.Despite the greater plasma NEFA around parturition, cows with BCS 3.75 or higher seemed to have a more active system for catabolism of NEFA and utilization of glycerol within adipose tissue. A linkage between those pathways and risk of disorders postpartum remains to be determined.     

Processing tomato quality as affected by irrigation scheduling

In Southern Italy the paucity of water is a very important problem and due to the fundamental importance of the water for the processing tomato, in this study the influence of irrigation on processing tomato quality was investigated in the years 2002 and 2003. A hybrid processing tomato (Lycopersicon esculentum L. Mill cv. Ability) was treated with different water regimes obtained combining amount of water and irrigation interval. The effects of the trials were evaluated taking into account the physical and chemical characteristics of the fruits, as well as the content in antioxidants moieties. Furthermore, the relationship among all the quality parameters and the seasonal amount of irrigation water was evaluated.The results, comparing different water regimes obtained combining amount of water and irrigation interval, gave useful indications on the possibility to improve nutritional tomato quality by reducing irrigation water during tomato cropping. In particular, relatively to the Mediterranean areas of tomato cultivation and to the texture of the soil considered in this study, the best compromise between quality and quantity of the processing tomato fruit was achieved both with the extension of the irrigation interval (L40 or L60) and with the limitation of irrigation volume for the second part of the tomato crop cycle (thesis 100-50). Extending the irrigation interval and limiting irrigation volume for the second part of the tomato crop cycle, appeared to be the best management strategy to optimize the yield and nutritional quality of processing tomato.     

Synthesis of some new ether derivatives of hydroquinone and their ovicidal activity against the two-spotted spider mite (Tetranychus urticae Koch)

A new class of compounds derived from hydroquinone ethers showed high and predominantly ovicidal activity against the two-spotted spider mite, Tetranychus urticae Koch. The sequence of compounds synthesised and the factors which appeared to have contributed most to the discovery of these promising acaricides are presented.     

Hymenoptera wasps associated with the Asian gall wasp of chestnut (Dryocosmus kuriphilus) in Calabria,Italy

The parasitoid complex of the Asian chestnut gall wasp Drycosmus kuriphilus Yasumatsu was studied in Calabria (Italy). A total of 14 different species of parasitoids were collected, of which three are recorded on the Asian gall wasp for the first time. The composition of the parasitoid complex collected in Calabria was compared with that reported from Italy and from Europe. The altitude of the sites of collection seemed to have an effect on the distribution and abundance of the single species of parasitoids.