Determination of copper in infant formula by graphite furnace atomic absorption spectroscopy with a L'vov platform

A rapid method for the determination of sub-part-per-million levels of copper in infant formula, which does not require decomposition of the sample matrix before analysis, has been developed. The method uses L'vov platform graphite furnace atomic absorption spectroscopy (GFAAS), a technique that greatly reduces matrix interferences limiting the applicability of normal GFAAS. The sample preparation consists of dilution of a weighed sample of infant formula to a known volume with a 0.5% solution of Triton X-100 in deionized water. The accuracy of the method, as assessed from the results of overspike recovery studies (96.5-101.3% recovery) for different matrix types and comparison to results generated with alternative methodologies, can be considered excellent. The overall precision of the method ranges from 2.5 to 4.3% RSD for different matrix types.     

Model study on the effect of 15 phenolic olive mill wastewater constituents on seed germination and Vibrio fischeri metabolism

Olive mill wastewaters (OMW) can be a severe problem when disposed of as untreated because of their high organic load, elevated concentration of polyphenols, and moderately low biodegradability. In the present study, the acute toxicity of 15 compounds with low molecular weight (<350 Da), catechol, four benzoic acids, three phenylacetic acids, three phenylethanols, and four cinnamic acids, already isolated from the reverse osmosis in the fractionation of OMW, was assessed on the marine bacterium Vibrio fischeri and on the seeds of two dicotyledonous species Cucumis sativus and Lepidium sativum, and on one monocotyledon Sorghum bicolor. Results of phytotoxicity showed that the most toxic compounds were catechol (EC50s ranging from 0.40 mmol/L for S. bicolor to 1.09 for C. sativus) and hydroxytyrosol, (EC50s ranging from 0.47 mmol/L for S. bicolor to 1.55 for C. sativus) while the toxic potential on bacteria was particularly elevated with EC50 values 1 or 2 orders less than phytotoxicity. These results suggested that the risk of OMW disposal may be more elevated for the water compartment than for the soil.     

Anaesthesia with ketamine/medetomidine in the rabbit: influence of route of administration and the effect of combination with butorphanol

Objective To compare the characteristics of anaesthesia induced with ketamine/medetomidine administered by the subcutaneous and intramuscular routes and to assess the effects of the addition of butorphanol to this combination. Study design Prospective randomised study. Animals Six female New Zealand White rabbits. Methods Rabbits were given one of four combinations of ketamine and medetomidine (K/M) either subcutaneously (SC) or intramuscularly (IM) on four successive occasions with a 7‐day interval between treatments. The dose combinations were; 15/0.25 mg kg^?1 SC; 15/0.25 mg kg^?1 IM; 15/0.5 mg kg^?1 SC, and 15/0.25 mg kg^?1 together with 0.4 mg kg^?1 butorphanol (K/M/B) SC. The effects of anaesthesia on arterial blood gas values and cardiovascular variables were recorded at predetermined time points. Toe and ear pinch reflexes were judged to determine the duration of surgical anaesthesia. Loss of the righting reflex was used to measure the duration of sleep time. Analyses used repeated measures analysis of variance. Results All groups lost the righting reflex and ear pinch response. Three animals in the groups that received K/M alone lost their toe pinch reflex, whereas four lost this reflex when given K/M/B. Time of onset of loss of the righting, toe and ear pinch reflexes did not differ significantly among the groups. The higher dose combination of medetomidine with ketamine and the combination of K/M/B produced a greater duration of loss of the ear pinch response than the lower dose of K/M administered by either route. No significant differences were found among the groups in the duration of loss of the toe pinch reflex. All animals developed a moderate bradycardia (mean heart rate <166 beats minute^?1) and moderate hypoxaemia (mean P_aO₂ < 6.0 kPa). Animals given butorphanol showed the greatest reduction in respiratory rate (31 ± 13 breaths minute^?1, p < 0.05) but this was not reflected in any significant differences in arterial PCO₂, PO₂ or pH among the groups. Conclusions Administration of K/M by the SC route produced equivalent effects in comparison to intramuscular administration. The addition of butorphanol increased the duration of anaesthesia, but produced a slight increase in the degree of respiratory depression. All dose rates resulted in hypoxaemia so oxygen should be administered when these combinations are used in rabbits. Clinical relevance Subcutaneous administration is both technically simpler and may cause less discomfort to the animal than IM injection, and so is preferred. The combination of K/M with butorphanol has relatively minor effects on the depth and duration of anaesthesia, so offers little advantage to the use of K/M alone.     

Pesticidal seed coats based on azadirachtin‐A: release kinetics,storage life and performance

BACKGROUND: Infestation of seeds by pests during storage leads to deterioration in quality. Seed coating is an effective option to overcome the menace. Unlike synthetic fungicidal seed coats, little is known of those based on botanicals. This study aims at developing azadirachtin‐A‐based pesticidal seed coats to maintain seed quality during storage. RESULTS: Polymer‐ and clay‐based coats containing azadirachtin‐A were prepared and evaluated for quality maintenance of soybean seed during storage. Gum acacia, gum tragacanth, rosin, ethyl cellulose, hydroxyethyl cellulose, polyethyl methacrylate, methyl cellulose, polyethylene glycol, polyvinyl chloride, polyvinyl acetate, polyvinyl pyrrolidone and Agrimer VA 6 polymers and the clay bentonite were used as carriers. The time for 50% release (t_1/2) of azadirachtin‐A into water from the seeds coated with the different coats ranged from 8.02 to 21.36 h. The half‐life (T_1/2) of azadirachtin‐A in the coats on seed ranged from 4.37 to 11.22 months, as compared with 3.45 months in azadirachtin‐A WP, showing an increase by a factor of nearly 1.3–3.3 over the latter. The coats apparently acted as a barrier to moisture to reduce azadirachtin‐A degradation and prevented proliferation of storage fungi. Polyethyl methacrylate, polyvinyl acetate and polyvinyl pyrrolidone were significantly superior to the other polymers. Azadirachtin‐A showed a significant positive correlation with seed germination and vigour, and negative correlation with moisture content. CONCLUSION: Effective polymeric carriers for seed coats based on azadirachtin‐A are reported. These checked seed deterioration during storage by acting as a barrier to moisture and reduced the degradation of azadirachtin‐A. Copyright © 2008 Society of Chemical Industry     

Old and new diagnostic approaches for Q fever diagnosis: correlation among serological (CFT, ELISA) and molecular analyses

The objective of this study was to evaluate the performance of the complement fixation test (CFT) with respect to ELISA for the serological diagnosis of Q fever and to assess the role of serology as a tool for the identification of the shedder status. During 2009-2010, sera from 9635 bovines and 3872 small ruminants (3057 goats and 815 sheep) were collected and analyzed with CFT and ELISA. In addition, 2256 bovine, 139 caprine and 72 ovine samples (individual and bulk tank milk samples, fetuses, vaginal swabs and placentae) were analyzed with a real-time PCR kit. The relative sensitivity (Se) and specificity (Sp) of CFT with respect to ELISA were Se 26.56% and Sp 99.71% for cattle and Se 9.96% and Sp 99.94% for small ruminants. To evaluate the correlation between serum-positive status and shedder status, the ELISA, CFT and real-time PCR results were compared. Due to the sampling method and the data storage system, the analysis of individual associations between the serological and molecular tests was possible only for some of the bovine samples. From a statistical point of view, no agreement was observed between the serological and molecular results obtained for fetus and vaginal swab samples. Slightly better agreement was observed between the serological and molecular results obtained for the individual milk samples and between the serological (at least one positive in the examined group) and molecular results for the bulk tank milk (BTM) samples. The CFT results exhibited a better correlation with the shedder status than did the ELISA results.